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1
Morgado, dos Santos Ana Maria. "Plant factors influencing water use efficiency of wheat." Thesis, University of Reading, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434315.
Повний текст джерела
2
Moyer, Jeremy William. "Energy Efficiency Improvements for a Large Tire Manufacturing Plant." OpenSIUC, 2011. https://opensiuc.lib.siu.edu/theses/756.
Повний текст джерелаАнотація:
This study examines five potential improvement projects that could be implemented at the Continental Tire manufacturing plant located in Mount Vernon, IL. The study looks at insulating of tire molds, installation of variable frequency drives on circulating pumps, pressure reduction turbines, waste heat utilization used for absorption cooling, and cogeneration using a gas turbine cycle. A feasibility study and cost analysis was performed for each project to determine recommendation for implementation. The two most appealing projects are the insulation addition and the installation of variable frequency drives. Adding insulation would produce energy savings in the range of 908 kJ/s (3,097 Btu/hr) to 989 kJ/s (3,374 Btu/hr) and annual savings between $13,390 and $14,591. Installation of variable frequency drives on two 200 hp circulating pumps would produce energy savings between 74.6 kW (100 hp) and (104.6 kW (140.2 hp) with annual monetary savings in the range of $41,646 to $58,384.
3
Stangoulis, James Constantine Roy. "Genotypic variation in oilseed rape to low boron nutrition and the mechanism of boron efficiency." Title page, contents and summary only, 1998. http://web4.library.adelaide.edu.au/theses/09PH/09phs7856.pdf.
Повний текст джерелаАнотація:
Bibliography: leaves 132-159. Boron efficiency in oilseed rape (Brassica napua L. and B. juncea L.) was investigated in a wide range of genotypes. Using a solution culture screening of 10 day old seedlings, root length best described shoot growth response, and was used to characterise a total of 65 genotypes. Varieties and breeders lines tolerant of B-deficient growing conditions were identified, and the screening process validated through field trials. B responses in plants sampled at the 'green bud' stage indicated that vegetative growth is important in B efficiency. Studies were conducted to investigate the mechanism of B efficiency in oilseed rape. Results suggest no association between B efficiency and the capacity to acidify the root rhizosphere, or an increased translocation of B from root to shoot. Boron retranslocation was also studied as a mechanism of B efficiency.
4
Frantz, Jonathan M. "Determining the Factors That Control Respiration and Carbon Use Efficiency in Crop Plants." DigitalCommons@USU, 2003. https://digitalcommons.usu.edu/etd/6600.
Повний текст джерелаАнотація:
In the literature on plant respiration, there are two viewpoints concerning the source of respiratory control: supply (photosynthate availability) or demand (temperature dependent) limitations. While different studies indicate the primary dependency for respiration is either the supply or demand side, the two paradigms cannot both be true. The relative importance of each paradigm may depend on a number of factors including period of time during which respiration is measured, phase of plant development, environmental conditions, and species.
Studies were performed using continuous CO2 gas-exchange instrumentation to monitor short- and long-term changes in whole canopies of lettuce, tomato, soybean, and rice in response to changes in light and temperature during vegetative growth. Respiration in all crops was less sensitive to temperature than previously reported. This is likely due to large amounts of temperature-insensitive growth respiration as a fraction of total respiration during early growth. Carbon use efficiency (CUE) decreased with warm night temperatures, but the change was too small to decrease the final dry mass or carbon gain after night temperatures decreased. Canopies with constant day/night temperature had the same CUE, in elevated CO2 (1,200 μmol moJ- 1), regardless of temperature. In ambient CO2 (400 μmol mol-1), CUE decreased significantly when temperatures were above 32C.
Applying shade initially decreased CUE because of low photosynthesis and high respiration. After about 12 days, canopies acclimated, based on recovery of CUE. Different species acclimated to shade to different extents, but no interaction was evident between light and shade stress. These data were used to predict changes in photosynthesis, respiration, and carbon use efficiency given light, temperature, and CO2 concentrations.
5
Movahedi, Mahsa. "Identifying stomatal signalling genes to improve plant water use efficiency." Thesis, University of Sheffield, 2013. http://etheses.whiterose.ac.uk/4539/.
Повний текст джерелаАнотація:
Water is lost from higher plants via transpiration through stomatal pores the aperture of which is regulated by pairs of guard cells. Genetic engineering of the guard cell abscisic acid (ABA) signalling network that induces stomatal closure under drought stress is a key target for improving crop water use efficiency. In this study experiments were designed to investigate whether the biochemical mechanisms associated with the N-end rule pathway of targeted proteolysis could be involved in the regulation of stomatal apertures. The results indicate that the gene encoding the plant N-recognin, PRT6 (PROTEOLYSIS6), and the N-end rule pathway, are important in regulating stomatal ABA-responses in addition to their previously described roles in germination and hypoxia. Direct measurements of stomatal apertures showed that plants lacking PRT6 exhibit hypersensitive stomatal closure in response to ABA, and IR thermal imaging revealed reduced evapotranspiration under drought-stress. Together with a reduction in stomatal density, these properties result in drought tolerant plants. Plants lacking PRT6 are able to synthesis NO but their stomata do not close in response to NO suggesting that PRT6 is required for stomatal aperture responses to NO. Double mutant studies suggested that PRT6 (and by implication the N-end rule pathway) genetically interacts with known guard cell ABA signalling components OST1 and ABI1, and that it may act either downstream in the same signalling pathway or in an independent pathway. Several other enzymatic components of the plant N-end rule pathway were also shown to be involved in controlling stomatal ABA sensitivity including arginyl transferase and methionine amino peptidase activities. These results indicate that at least one of the N-end rule protein substrates which mediates ABA sensitivity has a methionine-cysteine motif at its N-terminus. A separate set of experiments were designed to investigate whether stomatal ABA-signalling pathways could have been conserved throughout land plant evolution. Cross-genetic complementation experiments were carried out to determine whether Physcomitrella stomatal apertures are able to respond to ABA and CO2 using a similar signalling pathway to that of flowering plants. The results demonstrated involvement of OST1 and ABI1 orthologues indicating that the stomata of the moss respond to ABA and CO2 using a signalling pathway that appears to be directly comparable to that of the model flowering plant Arabidopsis thaliana.
6
Opara, Chigozie Ethelvivian. "Energy Efficiency of the HVAC System of a Power Plant." OpenSIUC, 2015. https://opensiuc.lib.siu.edu/theses/1741.
Повний текст джерелаАнотація:
This study models the HVAC system of a power plant. It involved Computer simulations to study the energy demand by the HVAC system of the power plant as well as the energy demand of the system with modifications on the plant such as the building materials, use of energy efficient lighting, etc. Further studies on the energy demand of the system with the power plant located at different regions of the country were done to understand the effects of climate and locations. It is important to have an understanding of how a plant generating energy uses it for Heating, Ventilating and Air conditioning within the power plant building itself. This study has provided a better understanding of the energy use and how the HVAC system use in the offices and other areas located in the power plant building operates. The study included implementation of energy efficient measures in the choice of building materials for the building. The U.S. Department of Energy (DOE) EnergyPlus program was used to model the HVAC system of the power plant making use of the parameters and modified parameters of the power plant. The results of this study show that the energy demand of the HVAC system of a power plant is significantly affected by the choice of materials for the building. It was found that there is a reduction in the power demand of the HVAC system of the plant by about an average of about 21.7 % at the different the locations. It was also found that this resulted in the amount of energy saved per year of about 87,600 kWh. This gives an average cost savings per year of about $10,512.
7
Wynn, Paul Laurence. "Water use efficiency and drought resistance in ornamental plants." Thesis, The University of Sydney, 2009. https://hdl.handle.net/2123/28220.
Повний текст джерелаАнотація:
Increasing concerns over the distribution, abundance and security of fresh water
resources in Australia have led to a nationwide re—evaluation of their management and
sustainability. The potential for reductions in municipal water use through demand
management are substantial, including the potential for savings through the improved
design and management of the irrigated urban landscape. It is proposed that the
selection of more appropriate plant species is essential to maximising outdoor water
savings. Current plant selection practices are, however, typically based upon highly
questionable and potentially flawed anecdotal evidence. Ideally, these decisions
should stem from detailed investigation of the water requirements, drought tolerance
and water use efficiency (WUE) of specific plants. Such investigation forms the basis
of this thesis. An extensive range of ornamental plant species were therefore
examined, chosen based on their origin (native vs. exotic) and aesthetic function or
utility in the landscape. It was hypothesised that those plants of Australian origin, due
to the frequency of drought in their native habitats, would demonstrate more tolerance
to water stress than their exotic counterparts. In the first of three experiments, plants
were subjected to varying levels of drought stress using differential rates of irrigation,
each replacing a fixed percentage of potential evapotranspirational demand. Plant
recovery capacity was subsequently assessed during an extended well—watered period.
A range of physiological parameters was monitored and, using digital image analysis,
changes in the level of foliar display and canopy transparency were assessed as
objective measures of plant ornamentality and amenity value. Development of an
improved method of imposing drought stress, for use in a subsequent study, involved
a separate detailed assessment of a high molecular weight polymer,
polydiallyldimethylammonium chloride (PDADMAC), which demonstrated its
significant potential as an osmoticum. A detailed and intensively monitored third
experiment was carried out with two groundcover species, the exotic Lobularia
maritima (Sweet Alyssum) and the Australian native Chrysocephalum apiculatum
(Yellow Buttons), each previously revealed as having particularly high WUE and
drought tolerance. Each species was subjected to one of several rates of drought
stress imposition using frequent incremental additions of PDADMAC to an air-lift
irrigation system followed by a period of recovery. A similar range of physiological
parameters was monitored in this study, in addition to carbon isotope discrimination
measurement and a microscopic examination of leaf surface morphology. There was
a high level of concurrence between the studies, with the plants of Australian origin
generally exhibiting superior drought resistance and higher WUE than the exotic
plants examined. The native plants typically maintained higher levels of foliar
display and exhibited higher net photosynthesis rates, transpiration rates and final
shoot dry weights than the corresponding exotics. The natives also maintained lower
overall leaf water potentials, both in the absence and presence of drought stress,
possibly enabling the positive water balance in plant tissues through the creation of a
strong water potential gradient between plant and soil. C. apiculatum appears to have
utilised other traits and strategies for its superior performance under drought stress,
including its contrasting phenology to L. maritima and its greater level of pubescence.
During recovery, the natives also demonstrated a greater overall capacity for
regeneration than the exotics, as measured by foliar gains. The effect of decreasing
water availability was also highly consistent across the studies, with decreasing water
availability producing overall declines in foliar display, foliar display—based WUE, net
photosynthesis rates, leaf water potentials, final shoot dry weights, survival times and
general plant health. Based upon the implications of these findings, a number of
practical recommendations were developed for use in the design and management of
water conserving urban landscapes.
8
Jayasinghe, Prabodha. "Development of a tool for simulating performance of sub systems of a combined cycle power plant." Thesis, KTH, Energiteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-99164.
Повний текст джерелаАнотація:
Abstract In Sri Lanka, around 50% of the electrical energy generation is done using thermal energy, and hence maintaining generation efficiencies of thermal power plants at an acceptable level is very important from a socio-economic perspective for the economic development of the country. Efficiency monitoring also plays a vital role as it lays the foundation for maintaining and improving of generation efficiency. Heat rate, which is the reciprocal of the efficiency, is used to measure the performance of thermal power plants. In combined cycle power plants, heat rate depends on ambient conditions and efficiencies of subsystems such as the gas turbine, Heat Recovery Steam Generator (HRSG), steam turbine, condenser, cooling tower etc. The heat rate provides only a macroscopic picture of the power plant, and hence it is required to analyse the efficiency of each subsystem in order to get a microscopic picture. Computer modelling is an efficient method which can be used to analyse the each subsystem of a combined cycle power plant. Objective of this research is to develop a computer based tool which simulates the performance of subsystems of a combined cycle power plant in Sri Lanka. At the inception of the research, only heat rate was measured, and performances of subsystem were unknown. During the analysis, plant is divided into main systems, in order to study them macroscopically. Then, these main systems are divided into subsystems in order to have a microscopic view. Engineering equation solver (EES) was used to develop the tool, and the final computer model was linked with Microsoft excel package for data handling. Final computer model is executed using both present and past operating data in order to compare present and past performance of the power plant. In combined cycle power plants steam is injected into the gas turbine to reduce the NOx generation and this steam flow is known as NOx flow. According to the result it was evident that turbine efficiency drops by 0.1% and power output increase by 1MW when NOx flow increases from 4.8 to 6.2kg/s. Further it was possible to conclude that gas turbine efficiency drop by 0.1% when ambient temperature increased by 3 C; and gas turbine power output decrease by 2MW when ambient temperature increases from 27 to 31 degrees. Regarding the steam cycle efficiency it was found that steam turbine power output drops by 0.5MW when ambient temperature increases from 27 to 31 degrees; and steam cycle efficiency increases by 1% when NOx flow increases from 4.8 to 6.2kg/s. Further, steam turbine power output decreases by 0.25MW When NOx flow increases from 4.8 to 6.2kg/s Heat rate, which is the most important performance index of the power plant, increases by 10units (kJ/kWh) when ambient temperature increases by 3 C. Heat rate also increases with raising NOx flow which was 6.2kg/s in 2007 and 4.2kg/s in 2011. Hence, heat rate of the power plant has improved (decreased) by 10units (kJ/kWh) from 2007 to 2011. Other than above, following conclusions were also revealed during the study. 1) HRSG efficiency has not change during past 4 years 2) Significant waste heat recovery potential exists in the gas turbine ventilation system in the form of thermal energy
9
Qin, Guixiang. "Development of advanced ferritic steels for high efficiency power generation plant." Thesis, University of Leicester, 2009. http://hdl.handle.net/2381/9944.
Повний текст джерелаАнотація:
E911 creep samples exposed to temperatures of 600˚C, 625˚C and 650˚C at differing stress levels were supplied by CORUS. The hardness of the gauge length that experienced both creep strain and temperature was found to be lower than that of the head where thermal softening only can be assumed. The changes in the morphology and size of precipitates were observed qualitatively by optical microscopy and Scanning Electron Microscopy. A creep fracture mechanism map of E911 steel was constructed with two modes of creep (transgranular and intergranular ). A fitted ellipse shape was used to characterise the irregular block shape by Electron Backscattered Diffraction (EBSD). It showed that the width of the block inside a prior austenite grain increases more rapidly in the gauge length than in the head; subgrain growth was also observed by EBSD. Transmission Electron Microscopy studies indicate that at 600°C E911 steel can reach up to 75647 hours creep rupture life (108MPa), which is due to the relatively small size of M23C6, Laves and M2X phases. However, Z phase precipitation results in a drop in creep resistance owing to the dissolution of fine MX phase and the transformation of M2X phase. At 625°C and 650°C, the creep rupture life decreases owing to the coarsening of Laves, M23C6 and M2X phases. Four experimental steel casts were prepared with varying levels of Ni and Cr to investigate the effect of these elements on Z phase formation. After 10,000 hours exposure, there was little evidence of Z phase in the samples studied and therefore it is difficult to draw definitive conclusions about the role of Ni or Cr in promoting Z phase formation. It is possible that the casts studied here will allow better conclusions to be drawn after exposing the samples to longer durations.
10
Polozhiy, S. "Grounding of ecological and economical operating efficiency of hydroelectric power plant." Thesis, Видавництво СумДУ, 2009. http://essuir.sumdu.edu.ua/handle/123456789/8240.
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11
Parmar, Anisha. "Exploiting resource use efficiency and resilience in ancient wheat species." Thesis, University of Nottingham, 2014. http://eprints.nottingham.ac.uk/14515/.
Повний текст джерелаАнотація:
Modern bread wheat (Triticum aestivum) initially derived from wild progenitors which underwent hybridisation and domestication events. It is hypothesised that modern plant breeding has reduced the genetic variation among modern cultivars (Sparkes, 2010). Ancient wheat species form a conduit between wild ancient wheat and cultivated Triticum species, and may harbour the genetic variation required to supplement the modern bread wheat gene pool. The current work investigated a range of morphological and physiological aspects of several ancient species including several representatives of spelt, emmer and einkorn. These were compared to modern bread wheat in two field and three glasshouse experiments with the aim to investigate their resource use efficiency, where radiation use and water use formed the crux. The main components of the current work relate to 1) canopy interception characteristics 2) leaf photosynthetic capabilities and 3) water use. Spelt genotypes demonstrated increased WUE and green area longevity compared with modern bread wheat. Emmer displayed increased WUE, assessed on three scales using instantaneous transpiration efficiency (ITE), biomass to water uptake ratios, and carbon isotope discrimination (Δ13C). In addition, the mechanisms whereby emmer, einkorn and spelt maintained ITE appeared to differ. Emmer was observed to increase photosynthetic rates, whereas spelt maintained low transpiration as a result of low stomatal conductance. Einkorn however, maintained ITE through an intermediate of both of these mechanisms. This was further supported by species differences for maximum photosynthetic rates (Asat) which, for emmer and einkorn, were comparable with modern bread wheat. Investigation of WUE through Δ13C and biomass production to water uptake ratios ranked species similarly, showing emmer and spelt to have superior WUE during grain filling. Additionally, spelt was observed to produce biomass comparable to modern bread wheat, thought to be due to enhanced RUE (observed in one field trial) or increased green area longevity rather than increased assimilation capability. In field experiments, biomass production and light interception was relatively high for einkorn species, however this was believed to derive from excessive tiller production due to poor emergence. Overall, ancient species did partition a larger proportion of assimilates toward tillers. Modern bread wheat produced fewer tillers, but directed more biomass towards the ear, and therefore had greater harvest indices (HI) compared to all ancient species. Despite this broad analysis, further investigation of the mechanisms responsible for these traits is required. This research therefore indicates that there is sufficient variation for traits, which could be used to improve radiation and water use efficiency, and therefore warrants further exploration. With further investigation, resource capture and utilisation efficiency, and the morphological traits that confer these advantages in these genotypes, genetic markers could be identified with the aim to introduce valuable traits for the production of novel modern bread wheat varieties. The differences observed between these ancient wheat species and modern bread wheat provide an opportunity through which modern wheat gene pools may be improved to stabilise yields, particularly in sub-optimal environmental conditions, thus increasing biomass production per unit resource, thereby enhancing the productivity and the efficiency of crop systems.
12
Atherton, Jon Mark. "Multiscale remote sensing of plant physiology and carbon uptake." Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/6219.
Повний текст джерелаАнотація:
This study investigated the use of optical remote sensing for estimating leaf and canopy scale light use efficiency (LUE) and carbon exchange. In addition, a new leaf level model capable of predicting dynamic changes in apparent reflectance due to chlorophyll fluorescence was developed. A leaf level study was conducted to assess the applicability of passive remote sensing as a tool to measure the reduction, and the subsequent recovery, of photosynthetic efficiency during the weeks following transplantation. Spectral data were collected on newly planted saplings for a period of 8 weeks, as well as gas exchange measurements of LUE and PAM fluorescence measurements. A set of spectral indices, including the Photochemical Reflectance Index (PRI), were calculated from the reflectance measurements. A marked depression in photosynthetic rate occurred in the weeks after outplanting followed by a gradual increase, with recovery occurring in the later stages of the experimental period. As with photosynthetic rate, there was a marked trend in PRI values over the study period but no trend was observed in chlorophyll based indices. The study demonstrated that hyperspectral remote sensing has the potential to be a useful tool in the detection and monitoring of the dynamic effects of transplant shock. Relationships between hyperspectral reflectance indices, airborne carbon exchange measurements and satellite observations of ground cover were then explored across a heterogeneous Arctic landscape. Measurements were collected during August 2008, using the University of Edinburgh’s research aircraft, from an Arctic forest tundra zone in northern Finland as part of the Arctic Biosphere Atmosphere Coupling at Multiple Scales (ABACUS) study. Surface fluxes of CO2 were calculated using the eddy covariance method from airborne data that were collected from the same platform as hyperspectral reflectance measurements. Airborne CO2 fluxes were compared to MODIS vegetation indices. In addition, LUE was estimated from airborne flux data and compared to airborne measurements of PRI. There were no significant relationships between MODIS vegetation indices and airborne flux observations. There were weak to moderate (R2 = 0.4 in both cases) correlations between PRI and LUE and between PRI and incident radiation. A new coupled physiological radiative transfer model that predicts changes in the apparent reflectance of a leaf, due to chlorophyll fluorescence, was developed. The model relates a physically observable quantity, chlorophyll fluorescence, to the sub leaf level processes that cause the emission. An understanding of the dynamics of the processes that control fluorescence emission on multiple timescales should aid in the interpretation of this complex signal. A Markov Chain Monte Carlo (MCMC) algorithm was used to optimise biochemical model parameters by fitting model simulations of transient chlorophyll fluorescence to measured reflectance spectra. The model was then validated against an independent data set. The model was developed as a precursor to a full canopy scheme. To scale to the canopy and to use the model on trans-seasonal time scales, the effects of temperature and photoinhibition on the model biochemistry needs to be taken into account, and a full canopy radiative transfer scheme, such as FluorMOD, must be developed.
13
Sohel, Mohammed Imroz. "Thermodynamic Modelling and Simulation for High Efficiency Design and Operation of Geothermal Power Plants." Thesis, University of Canterbury. Mechanical Engineering, 2011. http://hdl.handle.net/10092/5292.
Повний текст джерелаАнотація:
This thesis analyses long term and short term environmental effects on geothermal power plant performance and discusses adaptive ways to improve performance. Mokai 1 geothermal power plant has been used as a case study for this investigation. Mokai 1 is a combined cycle plant where the binary cycles are air-cooled. The plant performance of an air-cooled binary cycle geothermal power plant is dependent on the environment (resource characteristics as well as weather conditions). For modelling such a power plant, two time scales are of interest: the yearly basis for aggregate plant performance for design and operations; and the daily basis for hourly plant performances for an accurate dispatch prediction.
Adaptive methodology for long term performance improvement has been introduced in this work which would save money and effort in the future by keeping the provisions to adapt to changes in resource characteristics based on geothermal reservoir modelling. The investigation was carried out using a steady state computer simulator of Mokai 1 geothermal power plant. The steady sate simulator was built specifically for this work. The deviation in performance of various components is less than 5% compared to the original plant design. The model is very generic and it can be used for other plants with simple adaptation or can be used for future plant design.
One of the main contributions of this work is an iterative method for modelling the environmental effect on short term performance on the air-cooled organic Rankine cycle. The ambient temperature is identified as the most influencing parameter on short term performance which influences the performance of the whole cycle in two ways. Firstly, by changing the equilibrium pressure inside the condenser, the turbine outlet pressure changes and hence, the turbine pressure ratio also changes. The turbine pressure ratio is a major parameter determining power generated by a turbine; therefore, the plant output is affected. Secondly, by changing the condenser outlet temperature with the ambient temperature, the pump inlet and outlet condition and consequently vaporizer equilibrium temperature and pressure are influenced. The developed method sought the equilibrium conditions of both condenser and vaporizer iteratively. In short, ORC cycle shifts on the T-s plane depending on the ambient temperature. This method iteratively seeks the shifted ORC on the T,s plane.
Two case studies have been carried out to demonstrate the method. The developed method shows robustness and converges exponentially. The model is effective for cycles that use saturated vapour as well as superheated vapour. The model essentially assumes steady state operation of the power cycle. The possible unit time where this model can be applied is bounded by the time required by a system to come into steady state. The saturated vapour cycle yielded average error 4.20% with maximum error 9.25% and the superheated vapour cycle yielded average error 2.12% with maximum error 5.60%. The main advantage of the developed method is that it requires a minimum number of inputs: condenser (p,T), vaporizer (p,T), condenser heat load, turbine efficiency (overall), pump work and the extremum conditions of all the components. These inputs should represent typical operating conditions of a plant. The model can predict the appropriate plant performance depending on the system heat input (geothermal fluid flow in this case) and the heat sink temperature. As the method is based on basic thermodynamics rather than empirical or semi-empirical approaches, this method is widely applicable. The main focus of this work is on the ORC but the developed method is applicable to any closed Rankine cycle. In addition, application of the developed iterative method to predict plant performance based on mean yearly weather data is also discussed in the thesis.
Water-augmented cooling system and optimization of plant operating point parameters have been proposed as adaptive measures to improve short term performance. Developed iterative method has been used for the short term performance analysis. The water-augmented cooling system is specifically suitable to mitigate the reduced power output during the summer. The simulated average gain in power during the summer (Jan, Feb, Nov and Dec) of an ORC of Mokai 1 geothermal power plant by incorporating a water-augmented cooling system was 2.3% and the average gain for the whole year was 1.6% based on the weather data of Taupo for the year 2005. A cost benefit analysis showed that water-augmented cooling system is more economical compared to other alternative renewable energies considered to meet summer peak demand. From the green house gas emissions perspective, water-augmented cooling is a better option than the gas fired peaking plants.
Adaptive approach for short term performance improvement by optimizing operating point parameters of an air-cooled binary cycle has huge potential with possible maximum improvement in power output by about 50%. The optimization takes in to account the effects of the geothermal resource characteristics and the weather conditions. The optimization is achieved by manipulating cycle mass flow rate and vaporizer equilibrium condition. Further study on the optimizing operating points to achieve improved short term performance has been recommended for future work.
14
Leach, Richard Charles. "Characterisation of a 4BS.4BL-5RL wheat rye translocation to improve copper efficiency of bread wheat." Title page, table of contents and summary only, 2004. http://hdl.handle.net/2440/37937.
Повний текст джерелаАнотація:
Copper deficiency causes significant annual losses in grain yield due to poor grain set. Cereals such as wheat and barley are particularly susceptible to low copper soils whereas,crops such as rye and triticale are better able to grow and yield under such conditions of nutrient stress. The ability of rye and triticale, which carries a complete set of rye chromosomes, to tolerate low copper conditions has been attributed to a gene on rye chromosome 5R. Wheat-rye translocation lines have previously been produced carrying segments of the long arm of chromosome 5 of rye (5RL). Although these lines have expressed copper efficiency in University of Adelaide trials, until now they have been considered agronomically inferior and so have not been used as commercial cultivars. The physical size of rye segment of the 4BS.4BL-5RL translocation in a Chinese Spring background derived from the Cornell Wheat Selection 82a1-2-4-7 was measured using GISH (genomic in situ hybridization) and found to be 16% of the long arm. The size of this translocation was similar to GISH measurements of another 4BS.4BL-5RL translocation in Viking wheat background, although both these lines arose spontaneously and at different times. Molecular maps of both 4BS.4BL-5RL translocations in the two different wheat backgrounds were developed and used to screen for rare recombinants between wheat and rye in a background homozygous for the Sears' ph1b mutant. The maps revealed the approximate genetic location of the translocation breakpoint involved in these two 4BS.4BL-5RL translocations to be similar even though they are known to have arisen at different times and in different experimental populations. The similarity of these translocations suggests a unique property of the region at or near the translocation breakpoint that could be responsible for their similarity and spontaneous formation. After screening 703 critical seedlings for evidence of recombination between the 5RL segment and wheat homoeologues, no confirmed recombinants were identified. Lines containing the 4BS.4BL-5RL translocation were shown to yield equally as well as their recurrent parent under normal field conditions. In addition the presence of the 4BS.4BL-5RL had no adverse effects on a range of grain quality characteristics measured in these lines. A pot trial using lines derived from a cross between the CSHN translocation and the wheat cultivar Warigal (five backcrosses) revealed that they provided copper-efficiency even under the severest of deficiency conditions. While the results of this pot trial did not show the outstanding copper efficiency previously observed in these lines, the translocation did consistently out yield the recurrent parent under severe copper deficiency conditions. Finally, a reliable PCR marker was developed for the rapid identification of lines containing the distal portion of the 5RL chromosome.Thesis (Ph.D.)--School of Agriculture and Wine, 2004.
15
Anticona, Lizama Leslie Sofía, and Yzquierdo Eylin Fabiana Medina. "Increasing the efficiency level of loading operation in a fuel distribution plant." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2020. http://hdl.handle.net/10757/653602.
Повний текст джерелаАнотація:
Este artículo tiene como objetivo solucionar el problema de ineficiencia, representado por el bajo nivel de servicio en el sistema de distribución de la planta de combustible, ya que se han presentado retrasos desde el inicio del proceso hasta el final de este. Por este motivo, se analizó todo el flujo del sistema para determinar en qué parte del proceso estaba la causa principal, lo que ayudaría a reducir considerablemente el problema. Se propuso aplicar un sistema de citas para estandarizar los tiempos de servicio, así como la implementación de un algoritmo y el uso de mecanismos eficientes para derivar la mejor solución robusta que responda a todas las incertidumbres con tiempos de ejecución reducidos.This article aims to solve the inefficiency problem, represented by the low service level, in the fuel plant distribution system, since there have been delays from the beginning of the process to the end of this. For this reason, the entire flow of the system was analyzed in order to determine where in the process the main cause was, which would help reduce this problem considerably. It was proposed to apply an appointment system to standardize service times as well as the implementation of an algorithm and the use of efficient mechanisms to derive the best robust solution that responds to all uncertainties with reduced execution times.
Trabajo de investigación
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Seyed, Jabbari Seyed Shervin. "Phytoremediation efficiency: assessment of flow system and plant performance in constructed wetland." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
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Water is one of the most basic human needs for survival, though, there is a shortage in the amount of drinking water around the globe. Thus, preserving the quality of available water should be of high importance for us. For this purpose, we must treat water, used in every aspect of human activity, before releasing it back to the water bodies. With an increased inclination towards sustainability and green technologies, Constructed Wetlands (CW) are getting more attention as a more eco-friendly treatment for wastewater rather than conventional treatment plants.
There are different types of CW operating around the world with a different typology of plants vegetated in them. The aim of this Thesis is to compare these differences to find the best combination for improving CW performance for wastewater treatment. Different case studies throughout Italy have been examined for this matter. Many of these cases, used Hybrid CW rather than a single stage of either Vertical Subsurface Flow CW (VSSF) or Horizontal Subsurface Flow CW (HSSF), and usually, there is a Floating Treatment Wetland (FTW) as a tertiary step for further refining water quality before releasing it. This kind of Treatment setup for CWs shows an increased abatement efficiency for wastewater.
Lastly, vegetations in CW usually improve the efficiency of wetland performance. The important parameters in selecting macrophytes are their survivability and adaptability in wetland conditions. Among the macrophytes encountered Phragmites Australis and Iris Pseudacorus generally showed a higher growth performance and more adaptability in CW conditions.
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Baburai, Nagesh Aravinda Kumar. "The physiological and genetic bases of water-use efficiency in winter wheat." Thesis, University of Nottingham, 2006. http://eprints.nottingham.ac.uk/11398/.
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Winter wheat (Triticum aestivum L.) is the most extensive arable crop in the UK grown on about 2M ha p.a. There is a need to identify traits to ameliorate yield losses to drought which are on average about 15% per year. These losses will be exacerbated with predicted climate change. The overall objectives of the present study were to investigate the physiological and genetic bases of water-use efficiency (ratio of above-ground dry matter production to evapotranspiration; WUE) in winter wheat grown in UK conditions and to quantify relationships between WUE and yield performance under drought. The present study used a doubled haploid (DH) population of 33 lines derived from a cross between Beaver and Soissons, known from previous work to contrast for WUE. Two glasshouse experiments (2002/3 and 2003/4) and two field experiments (one at ADAS Gleadthorpe, Nottinghamshire in 2002/3 and the other at Sutton Bonington, University of Nottingham in 2004/5) were conducted. In the glasshouse experiments, two irrigation treatments (with and without irrigation) were applied to four genotypes (two parents and two DH lines), and in the field two irrigation treatments (rainfed and fully irrigated) were applied to the two parents and the 33 DH lines. A range of physiological traits was measured, including developmental stages, carbon isotope discrimination (Δ13C), leaf gas-exchange variables, green areas and biomass at sequential samplings, and these traits were related to grain yield. Transpiration efficiency (ratio of above-ground dry matter production to transpiration; TE) was assessed using the established inverse relationship between TE and Δ13c. In the glasshouse, WUE measured as the regression slope of dry matter on water use, did not differ amongst genotypes in 2003, but did in 2004. Soissons showed higher WUE than other genotypes under irrigation, and also higher WUE than Beaver under drought. For measurements of TE according to Δ13. Soissons and line 134G showed lower Δ13C values (higher TE) than line 134E and Beaver (P<0.05) in 2004 under both irrigation and drought. Soissons and line 134G showed consistently higher TE on account of lower stomatal conductance (gs ) and sub-stomatal C02 concentration (C) values. The early developing Soissons and line 134G exhibited greater flag-leaf green area persistence under drought than the late developing Beaver. Beaver tended to use more water than Soissons under both irrigation and drought, but reductions in water use under drought were similar amongst genotypes. Lower seasonal water use for Soissons than Beaver was associated with a smaller root system. There was a tendency for dry matter of Beaver to be more depressed under drought than Soissons in both the years. Overall, it was not possible to detect significant differences in biomass responses to drought amongst the genotypes, but there were consistent genetic differences in WUE and TE observed under both irrigated and droughted conditions. In the field experiments, the onset of drought coincided broadly with anthesis. The average grain yield losses under drought were 0.5 t ha-1 in 2003 and L6 t ha-1 in 2005. Averaging across site/seasons, Δ13C correlated positively with grain yield amongst the 35 genotypes under irrigation (r--0.35; P<0.05) and under drought (r--0.54; P<0.01), indicating a negative trade off between TE and yield. A 13C decreased under drought and a higher TE was associated with a reduction in average flag-leaf gs, measured from flag leaf emergence to anthesis + 4weeks. Stomatal conductance was measured for eight of the 33 DH lines including the parents, and there was a trend for lower Δ13C (higher TE) to be associated with lower gs, The genetic differences in gs, were generally associated with corresponding decreases in Ci and net photosynthetic rate (A). Therefore results suggested that the negative relationship between TE, as indicated by Δ13C and yield was associated with corresponding reductions in seasonal water use. There was a nonsignificant irrigation x genotype interaction at Gleadthorpe in 2003 and Sutton Bonington in 2005 for Δ13C indicating that this trait was of high heritability. There was an irrigation x genotype interaction for grain yield (P<0.05). A small number of genotypes showed higher yield associated with low Δ13C and these outlier lines could potentially be identified for breaking the negative linkage between yield and delta. In summary, WUE was negatively correlated with yield under drought in this population; and season-long water use appeared to be the most important component affecting yield levels under drought. It is suggested that selecting genotypes indirectly for high Δ13C (low WUE) may be a strategy to improve grain yield under drought. In the quantitative genetic analysis, the putative QTLs identified for target physiological traits were generally different at Gleadthorpe in 2003 and Sutton Bonington in 2005. The most confident putative QTLs for Δ13C were mapped on chromosomes 3B (LOD=2.32) and 2D (LOD=1.43). The identification of QTLs as potential candidate genes on these chromosomes may be associated directly with WUE in the Beaver x Soissons DH mapping population. The Δ13C QTL on chromosome 3B was detected commonly in both the irrigation environments and the direction of allelic effects was consistent with the parental differences in Δ13C. This QTL may therefore represent a novel gene for optimising WUE. It is suggested that breeders could optimise TE by selection according to a marker for this gene involving further fine-mapping to identify a marker tightly linked to the gene. Such a marker would also provide a target for gene discovery in future work. The results suggest that water use is the most important component of Passioura's yield model for yield improvement under UK conditions. Nevertheless, WUE and harvest index and their responses under drought will also likely play a role in yield improvement through breeding in the UK targeted at drought-prone environments in future years.
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Kunytsia, Maksym. "Energy audit of an industrial facility,Hagby waste management plant." Thesis, KTH, Industriell ekologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-192303.
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In order to answer modern challenges, which come from increasing needs in energy forprivate persons and industries as well as in order to decrease negative environmentalimpacts, caused by the processes of energy generation, it is important to constantly searchfor untapped energy efficiency potential. Moreover, nowadays, energy efficiency hasbecome one of the prerequisites of successful market competitiveness for any type ofindustry on local and global levels.An energy audit is an instrument, which can be used for understanding how the energy isused and identify possible energy-saving opportunities. It can be applied to a facility as awhole, as well as individually to equipment, system(s) or process(es). Moreover, energysaving measures can be both cross-cutting and sector-specific.The purpose of this project was to conduct a detailed energy audit of the Hagby wasterecycling plant and to identify beneficial energy saving opportunities from economic,environmental and social perspectives.In the frames of a preliminary energy audit 10 focus areas for further analysis wereidentified. For every area a baseline assessment of the current energy performance wasconducted, possible energy management opportunities were identified and evaluated aswell as results of each analysis were summarized. According to the results of the study, with the implementation of the suggestions, whichrequire no, low or medium investments it is possible to save 3,2% of the energy per year,which corresponds to 76 846 kWh. Energy consumption can further be decreased byimplementing measures, which need high initial financial investment. In that case totalsavings will be 468 846 kWh or 19,4% of total annual energy consumption. Additionalenergy might be saved just by introducing energy housekeeping measures. Finally,implementation of all the proposed EMO can bring 14,46 tons of 2 CO savings annually.Additional benefits of implementing the energy saving opportunities come from decreasingenvironmental impacts, improving working conditions of the plant employees and higherenergy security at the plant.The results of the energy audit can be a solid base for establishing an energy managementprogram at the plant, which will include performance targets, required resources and aclear procedure of realization of improvements. However, since some of the calculations inthe current study are based on various assumptions, after the company forms the energymanagement program, it is necessary to invite experts from industry in order to giveaccurate calculations for each of the focus areas.
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Bonyadi, Pour Roxanna. "Nitrogen use efficiency in plants : how roots and nodules are balanced in Medicago." Thesis, University of Warwick, 2014. http://wrap.warwick.ac.uk/73274/.
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Nitrogen availability is central to global food security. Understanding how plants respond to nitrogen could help develop crops with improved nitrogen use. This study aims to investigate how lateral root (LR) and nodule development are balanced in response to low (0.1 mM) and high (5 mM) NH4NO3 concentrations in the model legume Medicago truncatula var. Jemalong A17 using phenotypic and gene regulatory network analysis. High concentrations of NH4NO3 have an inhibitory effect on nodulation. The phenotypic measurements of root architecture of A17 in response to NH4NO3 and rhizobia showed that at high NH4NO3 rhizobia affected LR development. Total root size was less (P < 0.05) in rhizobia inoculated samples compared to the absence of rhizobia. This was due to a shorter primary root and less number of LRs. Whole genome profiling of early (2 and 6 hour) root responses to high NH4NO3 and rhizobia identified 4793 genes that were differentially expressed (significance cutoff of P<0.05). The early (2 and 6 h) responses to high NH4NO3 were mainly independent of the rhizobia effect and N-induction especially at 2 h time point was the predominant response. Some of the components of the autoregulation of nodulation (AON) pathway are also involved in LR development. The sunn-1 mutant is impaired in correct AON signals that lead to hypernodulation with short LRs at low N. Whole genome expression analysis of A17 and sunn-1 root samples identified 7186 significantly (P<0.05) expressed genes showing rhizobia and/or SUNN-regulated responses. These genes could be components of the AON pathway with putative role in balancing the number of nodules with LR development. Using motif analysis tools we identified motifs with putative promoters that were mainly Nodule specific cysteine rich peptides (NCRs). We suggest that these NCRs may be involved in regulating LR and nodule development depending on the plant N status.
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Zhang, Chenxi. "Nitrate Uptake of Kentucky Bluegrass as a Determinant of Nitrogen Use Efficiency." Thesis, North Carolina State University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3538535.
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Nitrate (NO3-) leaching from fertilized land can be detrimental to aquatic ecosystems and human health. Although NO 3- leaching potential is generally found to be low in turfgrass, certain conditions can occur that result in increased leaching loss of nitrogen. Kentucky bluegrass (Poa pratensis L.) is the most widely used cool-season turfgrass species in the temperate and subarctic climate zones in the United States. Due to its popularity, many new cultivars are bred and released each year. Despite the ample amount of information characterizing the agronomic features of Kentucky bluegrass genotypes, little is available documenting their physiological characteristics related to nitrogen use efficiency and how these might affect the NO3 - leaching potential of the genotypes. Such information would be of great value for both scientists and customers.
In this comprehensive study, a screening procedure was developed using nutrient solution culture to evaluate differences in NO3 - uptake among sixty Kentucky bluegrass genotypes. Two cultivars were selected from the sixty to represent genotypes having high vs. low capacity for NO3- uptake. These two cultivars were then used to examine the relationship between NO3- uptake efficiency and competitiveness for soil nitrogen. Finally, these two cultivars were compared to determine if NO3- uptake efficiency affected NO3- leaching potential.
There were significant differences in NO3- uptake at both high (1 mM) and low (0.05 mM) N concentrations among sixty Kentucky bluegrass genotypes, with a strong correlation between uptake rates at high and low N concentrations. Julia and Midnight were selected as representing cultivars with efficient and inefficient nitrate uptake, respectively. In nutrient solution culture, Julia exhibited 56% higher NO3 - uptake rates than Midnight. In a root competition study, in which the root systems of the two cultivars occupied the same soil volume, Julia was more competitive for nitrogen acquisition (absorbed 20 to 71% more NO 3- ) than Midnight. However, the higher NO3 - uptake capacity and better competitiveness for soil N in Julia did not result in lower NO3- leaching potential. These results suggest that differences in root morphology and architecture may play a more important role than uptake capacity in determining nitrate leaching potential among Kentucky bluegrass genotypes.
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Parker, Stuart J. "Supertargeting for multiple utilities." Thesis, University of Manchester, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302837.
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Häsänen, Lars. "Organizational death and employee motivation : Investigating a plant closure in a multi-plant organization." Doctoral thesis, Stockholms universitet, Psykologiska institutionen, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-43603.
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Major organizational changes are often connected with a variety of negative outcomes for both employees and the organization alike. As a contrast to this, organizational deaths have instead been associated with increased productivity and motivation to perform, despite certainty of job loss. These results have been regarded as counter-intuitive, since employment and job security are regarded as a foundation for work motivation. Consequently, this thesis aims at investigating the motivational aspects of organizational deaths in terms of change in motivation as individuals adjust to changing realities. The thesis rests on three empirical studies.The first study's results showed (contrary to theoretical postulations) that goal setting was able to influence employees' in-role and extra-role performance, job-induced tension, commitment to the closure, and job satisfaction. The second study showed that organizational productivity, efficiency, performance, motivation and psychological climate increased for both blue-collar and white-collar employees'. The results of the third study lend support to the anecdotal reports that high-performers stop performing during organizational deaths. However, this study also found that low-performers perceiving low justice increased their effort which may show that they have a personal gain in performing (e.g., positive self-perception). The results of the empirical studies support the notion that organizational productivity increases along with employees' motivation to perform. Finally, a common pattern in the data was that most positive variables increased and the negative variables decreased. These results are explained by the adoption of new goals, which creates horizontal coherence (harmony) among goals, which gives rise to goal proximity (motivation increases due to moving closer to the goal).At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: In press. Paper 2: Submitted. Paper 3: Submitted.
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Rafiee, Nima. "Process design and energy efficiency analysis of an oil and gas processing plant." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
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Abstract
The objective of this thesis is process design to prepare a heat and mass balance and associated equipment list that will process untreated reservoir fluids to allow export of saleable gas and oil in an oil and gas processing plant. Gas will be exported to an existing pipeline, oil to a nearby shuttle tanker. By energy efficiency analysis, some energy saving opportunities has been found such as heat integration, replacing control valves with expanders and improving pumps and compressors adiabatic efficiency and then the amount of power recovered through these opportunities have been calculated. After that by considering water added to the feed stream, gas dehydration unit is needed for gas drying. In this reason, a design of TEG dehydration unit has been done and compared with the energy consumption by molecular sieve dehydration unit. Comparison shows that molecular sieve dehydration unit consumes energy about two times more than TEG dehydration unit does. Furthermore, by designing fractionation unit and introducing dividing wall column, consumption of energy decreased about 33% in comparison with conventional columns. In the final part, some energy efficiency opportunities of pumps and compressors, which are the most energy consuming equipment in the oil and gas industries have been introduced. Moreover, the means of power generation for oil and gas plants have been studied. Most plants use gas turbine for power generation and introduce means of increasing gas turbine efficiency and its performance. In the final part some methods for recovery the low-grade heat, variable speed drive which shows significant energy saving, power recovery turbines and reducing friction losses through pipes have been defined.
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Chan, Lai Cheong. "Investigation on energy efficiency of electrical power system in Macau Coloane power plant." Thesis, University of Macau, 2012. http://umaclib3.umac.mo/record=b2586280.
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John-Bejai, Carus Kristoff Joel. "Wheat floral biology : prospects for improving the efficiency of hybrid seed production and abiotic stress tolerance." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/49925/.
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The modification of floral characteristics will be beneficial in improving the efficiency of hybrid seed production and the breeding of more climate resilient varieties in bread wheat (Triticum aestivum). Methods for phenotyping floral traits were initially tested using small genotype panels under controlled conditions and in field trials. Low-tech phenotyping methods appropriate for use by breeders and researchers were developed and demonstrated to be accurate. A panel of 111 genotypes was subsequently assessed in field trials using these methods. A high level of genotypic variation was observed for anther extrusion, anther length and anthesis duration/pattern and phenotypes were found to be stable across trials. Using this phenotypic data set, floral trait marker-trait associations (MTAs) were detected by association mapping and additional anther extrusion quantitative trait loci (QTLs) have been detected by linkage mapping in a bi-parental population. The phenotypic effects of candidate loci co-localizing with MTAs and QTLs were investigated using TILLING mutants and modifications to floral characteristics have been observed in some mutant lines. The utilization of phenotyping and genomic resources described in the present study is discussed and areas of future research have been identified.
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Brown, Jack. "The efficiency of selection in the early generations of a potato breeding programme." Thesis, University of St Andrews, 1988. http://hdl.handle.net/10023/7107.
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The efficiency of selection in the early generations of a potato breeding programme is examined. A number of unselected potato (Solanum tuberosum L) clones were grown in a glasshouse, from true botanical seed, and thereafter in the field at two locations (a seed site and a ware site) for three consecutive years. At each stage, a number of tuber characteristics were visually assessed and yield plus the yield components were recorded. Four potato breeders visually assessed the produce from each clone after harvesting each years trials and were in good agreement as to which clones would be selected in each environment. Selection for visually assessed characters in both the glasshouse and first clonal year produced a desirable response. However, such selection carried a high cost in terms of losing clones with commercial potential. Selecting clones for yield in the seedling and first clonal year was only marginally more effective than a random reduction in number of genotypes, while selection in the second clonal year appeared to be somewhat more effective as judged by performance in later generations. Comparison of a random sample of clones with ones from the same crosses which had been selected at the seedling and first clonal year stage was at best random, with some suggestion, however, of a negative effect. The causes behind the inefficiency of selection were found to be complex. The inefficiency was ascribed, at least in part, to (i) the inaccuracy of assessment on single plant plots; (ii) the "carry-over" effect of the mother tubers and (iii) selection under a short growing season. Although there was a formally significant interaction between progenies and environments, the rank of the mean of a cross remained relatively consistent over different growing conditions. It was found that the mean and square root of the variance obtained from breeders' preference in any of the environments provided a good basis for prediction of the number of clones in each cross which would exceed (or equal) a given target value. The square root of the variance added increasingly to the accuracy of the prediction as the target value increased but was never a major component in such predictions. When the predictions were used to provide ranking of the crosses, the rank correlations showed good agreement between the different environments and between observed and expected ranks. There was no evidence to suggest that univariate cross prediction for any of the other characters under study would not be effective. A new cultivar is unlikely to be successful simply because of high expression for a single character, but will rather be an all round improvement over cultivars already available. Three methods of multivariate cross prediction were therefore examined namely multivariate probabilities, sum of ranks and the frequency of genotypes in a sample that transgress set target values. The characters total tuber weigh t, mean tuber weight, number of tubers and regularity of tuber shape were examined. It was found that a sample as small as 25 clones provided good predictions (as judged by the observed frequencies in a larger progeny sample examined in various environments). The best estimates were obtained using multivariate probabilities based on the means, within progeny variances,. and the phenotypic correlations between variates. The ranking of crosses according to these multivariate probabilities provided good indications of the number of clones which survived selection in an actual breeding scheme. Thus it is suggested that an empirical examination of a sub-sample of the progeny from a cross could be used to determine the crosses which would have the highest probability of producing improved, potato cultivars. Selection of crosses rather than individual clones has several advantages which would favour such techniques being used in the early generations of a potato breeding programme. Cross prediction based on parental performance also provided an indication of the crosses, .and parents, .which would give the highest frequency of desirable recombinants. These predictions were not as accurate as those derived from examination of a sub-sample of progeny from each cross. But they would allow an earlier, and hence powerful, method of prediction.
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Griffiths, Marcus. "Identifying wheat root traits and regulatory genes for nitrogen uptake efficiency." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/48611/.
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Wheat (Triticum spp.) is a particularly important crop for food security, providing 20% of worldwide calorie intake. Food production is not meeting the projected global demand of an increase of 2.4% p.a. Improvement of resource capture in wheat could help meet this demand. Nitrogen (N) is an essential macronutrient for plant growth and development; however, nitrogen use efficiency (NUE) for cereal production is only 33%. Domestication of modern varieties of wheat may have lost potentially beneficial agronomic traits, particularly in the root system. Optimisation of root system architecture could profoundly improve nitrogen uptake efficiency (NUpE) and in turn increase the yield potential of the crop. Using ancestral wheat germplasm and mapping populations, desirable traits may be identified and bred back into commercial wheat varieties to increase yield potential. Using a high-throughput hydroponic root phenotyping system, N-dependent root traits have been identified in wheat mapping populations. Using transcriptomic analyses, the gene expression profile of a candidate N-dependent root QTL has been identified. Using a new root phenotyping system, X-ray micro-computed tomography (μCT), a three-dimensional representation of wheat roots can now be imaged in soil. A selection of the same mapping lines have been used for 3D μCT analysis based on field NUpE parameters to identify promising root traits in both seedlings and mature plants.
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Awan, Sajjad Zahoor. "Optimization of water use efficiency in tomato (Solanum lycopersicon L.) by transposition of an LeNCED1 transgene." Thesis, University of Warwick, 2012. http://wrap.warwick.ac.uk/49583/.
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The 9-cis-epoxycarotenoid-dioxygenase (NCED) is a key regulatory enzyme in ABA biosynthesis in plants and its overexpression increases ABA levels that can increase water use efficiency (WUE). The use of the „super promoter‟ (sp) to drive an LeNCED1 transgene in tomato greatly improved WUE without affecting long-term plant growth but caused delayed seed germination and reduced rates of seedling establishment. The first aim of the present study was to generate useful, novel variation in NCED transgene expression by allowing an LeNCED1 transgene, driven by a histone H2A promoter (pH2A), to transpose to new positions in the genome. A stabilized activator element linked to a GUS marker gene (sAc) was used to allow transposition of an engineered dissociation element (Ds) containing the LeNCED1 transgene of format Ds1::pH2A::LeNCED1::Ds2 (T-DNA-Ds). In F1 (sAc × Ds) plants transposition was demonstrated by detection of empty donor site through PCR. The F2 generation was screened for stable integration of the Ds element and reduced gs. Three F3 families, namely 59F3, 102F3 and 116F3, were investigated: they showed multiple stable Ds transposition events, had low gs, and a range of growth rates. Genotype 102F5 had wild-type seed germination, higher bulk leaf ABA and xylem sap ABA and 60% higher gravimetric WUE (WUEp). However, 102F5 accumulated 32% less above ground dry weight than wild type under well-watered conditions 56 days after germination. The sAc and Ds approach allowed production of T-DNA-Ds and nptII kanamycin free 102F5 line which retained transposed Ds (Tr-Ds) elements. These progeny were cross pollinated with sAc to reactivate the transposition of the LeNCED1 transgene and should be an excellent material for generating further variation in ABA content. The second aim was to overcome the seed dormancy in high ABA, genotypes such as sp5 and sp12, by testing novel hydroxamic acid NCED inhibitors for their ability to stimulate germination and seedling establishment. Improvement in seed germination in sp12 was observed with two hydroxamic acid compounds, and an increase in seedling growth rate was also observed, although this was not statistically significant.
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Khosla, Rajiv. "Yield and water use efficiency of different plant populations of dryland corn and sorghum." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-06112009-063140/.
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Sitzia, Tommaso. "The role of hedgerows as corridors for plant species: determinants analysis and efficiency evaluation." Doctoral thesis, Università degli studi di Padova, 2004. http://hdl.handle.net/11577/3425958.
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Fernando, K. M. C. "Exploration of favourable traits for nitrogen use efficiency in ancient wheat species." Thesis, University of Nottingham, 2015. http://eprints.nottingham.ac.uk/31015/.
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Nitrogen (N) fertiliser is one of the main inputs of intensive wheat cropping systems in the UK. The average application of N fertiliser in the UK for winter wheat was 220 kg N ha-1 in 2011, but typically only 50% of this applied N is taken up by the crop. Breeding crops for high N use efficiency (NUE; grain dry matter yield per unit availability of N from soil and/or fertiliser) while maintaining acceptable yield, is widely accepted as one of the approaches to maximise farmers’ revenue and minimise pollution risk by reducing N fertiliser application. NUE is divided into two components; N uptake efficiency (NUpE; crop N uptake per unit availability of N from soil and/or fertiliser) and N utilisation efficiency (NUtE; grain dry matter yield per crop N uptake). NUE can be improved by improving NUpE and /or NUtE. Targeted integration of favourable traits into breeding programmes needs adequate diversity of the existing genotypes. However, genetic diversity of modern bread wheat is narrowed due to chance hybridisation events during wheat evolution and selective breeding for high yield. Hence, it has become necessary to search for novel sources of genetic variation for NUE. One of the sources could be the ancient wheat species, which provide novel resources of genes to improve NUE of modern bread wheat. The overall objective of the current project is to explore favourable physiological traits for NUE in ancient wheat species. Three field experiments, four glasshouse experiments and three growth room experiments were conducted at Sutton Bonington Campus, University of Nottingham. The current work can be divided into four main components; (i) investigation of general plant growth and development, (ii) quantification of NUE and its components, (iii) exploration of root architectural traits of seedlings and mature plants, and (iv) identification of seedling root QTLs related to NUpE in a wheat x spelt population. Significant variation for plant establishment and development was identified among wheat species where bread wheat had high plant establishment and faster plant development compared to ancient wheat species. Above ground biomass production of bread wheat, spelt and emmer was either similar or bread wheat was slightly higher at maturity under high N levels (HN). However, high above ground biomass production at zero N (no N fertiliser; NN) was observed in spelt genotypes. High grain yield of bread wheat is due to improved harvest index when compared to tall ancient wheat species. Delayed onset of flag leaf senescence, slow senescence rate and prolonged leaf greenness were observed in some spelt genotypes, especially spelt cv. Oberkulmer and were positively associated with biomass production. Flag leaf length, width, green area, specific leaf area and SPAD values were significantly different between genotypes used in the study. The greatest green area, SPAD value and maximum width were recorded in bread wheat. NUE was higher in bread wheat followed by spelt, emmer and einkorn. Emmer 2 had higher NUpE than spelt, bread wheat and einkorn genotypes. Delayed senescence hence extended green area duration and deep and vigorous root system might have influenced NUpE of spelt genotypes. High fertiliser N recovery rate of emmer 2 may be associated with well distributed, shallow, horizontally grown root system, especially at early plant growth. NUtE of bread wheat is higher than ancient wheat species and closely related to harvest index and reduced plant height. NUtE is more controlled by genetic factors than NUpE. N supply has a negative relationship with NUpE and its components. Relationships between NUE and its components were not consistent between experiments in the study. However, NUpE and NUtE explained more of the variation in NUE under HN than NN. Root system architecture varied significantly between wheat species used in the study. Seminal root characters of the seedling such as tip angle, number of seminal roots, seminal root length and total root length are closely related to mature root systems. Spelt had long seminal roots with narrow tip angles and hence develops deep root system while having a well-developed superficial root system due to nodal roots. Therefore, both top soil scavenging and deep soil foraging occurs efficiently. A large and deep root system contributes significantly to greater above-ground biomass and green area production of spelt. A greater number of seminal roots with wide tip angles help emmer to develop a root system architecture well adapted to take up fertiliser N from the top soil layers, especially in early stage of the plant growth. There is a possibility of using seedling root traits such as total root length and average length of the seminal root to predict NUpE at maturity. Therefore, these traits might be used as selection criteria for crop breeding for efficient N uptake. Emmer had favourable seedling root traits related to NUpE while spelt showed more favourable root traits at for N uptake at maturity than modern bread wheat and einkorn. Root N uptake efficiency and specific absorption rate of N were higher in emmer than spelt, bread wheat and einkorn. Phenotypic evaluation and genetic analysis of recombinant inbred lines (RILs) produced from the cross between Swiss winter wheat variety Forno (Triticum aestivum) and Swiss winter spelt cv. Oberkulmer (T. spelta) was carried out. Two parents of the population were significantly different for a number of traits, including: number of seminal roots, average length of seminal roots, total root length, maximum width, width to depth ratio, tip angle and emergence angle of seminal root. All measured root traits of seedlings of the RILs varied significantly. A total of 26 significant QTLs were identified for seedling root traits. These QTLs were located on ten different chromosomes; 1BS, 2A, 2D, 3A, 3B, 4A, 5A, 5B, 7AL and 7D. QTL coincidence was found for total root length either with number of seminal roots or seminal root length of the seedlings which showed strong phenotypic relationship. RILs F5-10, F5-36, F5-134, F5 146, F5-230 and F5-234 could be efficient genotypes for N uptake at maturity. The contribution of the A genome to the phenotypic variation observed within this cross for the development of the seedling root system is more important than the B and D genomes, as assessed by QTL analysis. Further studies are needed to identify QTLs associated with NUpE and root architectural traits of emmer and spelt. Favourable root traits in emmer and spelt related to NUpE could be introduced to bread wheat through direct crossing or creating synthetic wheat. The introgression of spelt into modern bread wheat will be useful for molecular studies to develop marker assisted breeding for high NUpE.
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Fripp, R. N. "Design of digital controller for multivariable plants with actuator failures." Thesis, University of Salford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239978.
Повний текст джерела
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Terblanche, Ulrich. "Effective Use of Excess Heat in a Cement Plant." Thesis, KTH, Tillämpad termodynamik och kylteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-104080.
Повний текст джерелаАнотація:
The report investigates the feasibility of accessing waste heat at kiln 7 in the Cementa AB cement plant in Slite, Gotland. The background is provided, with a description of the cement manufacturing process. Most of the report concerns itself with the heat transfer capabilities of the plant, therefore a short description of the heat flow within the most essential equipment is provided. The investigation follows a set of steps to derive the conclusion. The first step investigates previous studies to obtain the three most feasible heat sources. The second step investigates the available heat of the selected sources. In the third step, accessing the source is discussed and investigated for both convection and radiation heat transfer methods. It also includes the sizing of the required heat exchangers. Using the new sources, the connection possibilities to existing infrastructure and its benefits are investigated in step four. The connections were made to the existing infrastructure used at kiln 8 for electrical generation and district heating supply. The selections of the most feasible solutions are provided based on heat recovery, payback period and practicality. The final step in the study provides for the final design, which consists of three possible connections or all of them combined. In the conclusion, the final design would provide for a reduction in oil burned, fuel consumption and CO2 emissions and an increase in electricity generated by the existing system. It is recommended that only one of the three connections be installed.The thesis was conducted at Cementa AB in Slite, Gotland. The supervisor at the plant was Fred Grönwall.
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Noronha, Sannervik Angela. "Modelling productivity of willow stands in Sweden : evaluation of concepts for radiation use efficiency and soil water and nitrogen availability /." Uppsala : Dept. of Short Rotation Forestry, Swedish Univ. of Agricultural Sciences, 2003. http://epsilon.slu.se/s286-ab.html.
Повний текст джерела
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Nehe, Ajit. "Identifying genetic diversity for improved nitrogen-use efficiency and associated physiological traits in wheat (Triticum aestivum L.) and wheat amphidiploids." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/48992/.
Повний текст джерелаАнотація:
Wheat is one of the most widely consumed staple crops in the world including India and its demand is increasing with increasing population. Increased grain yield (GY) has been associated with increased use of nitrogen (N) fertilizers which represent a significant environmental and production cost. Developing cultivars which have higher grain yield but use N efficiently may allow reduced fertilizer N inputs. The objectives of this study were to: (i) quantify the genetic variability in N use-efficiency (grain dry matter (DM) yield per unit N available from soil and fertilizer, NUE) in a panel of modern Indian wheat cultivars and find new genetic variation in a panel of amphidiploids produced by crossing hexaploid bread wheat with wild wheat relatives and (ii) identify traits and understand physiological mechanisms determining improved NUE to exploit for development of new N efficient cultivars. Thirty Indian elite bread wheat cultivars and 18 amphidiploid lines along with their five respective bread wheat parents were tested under high N (HN) and low N (LN) conditions in two years in field experiments at Agharkar Research Institute, Pune, India (2013 and 2014) and in glasshouse experiments at Nottingham University, UK, (2015 and 2016), respectively. Detailed growth analysis was conducted including GY, above-ground dry matter (AGDM), DM and N partitioning at anthesis and at harvest along with N remobilization efficiency (NRE) in the field experiment. Senescence kinetics of the flag-leaf were assessed from a visual score weekly from anthesis to complete canopy senescence in both sets of experiments. Physiological traits were assessed including flag-leaf light-saturated photosynthetic rate (Amax) under HN conditions in the field experiment and under both HN and LN conditions in glasshouse experiment. Flag-leaf relative chlorophyll content (SPAD) under HN and LN conditions was measured in both experiments; and Normalized Difference Vegetative Index (NDVI) under HN and LN conditions in field experiment. 2D seedling root phenotyping was carried out on subset of 12 genotypes selected based on contrasting performance under LN conditions from both the field and glasshouse experiments. In field experiments, GY was reduced under low N (LN) conditions on average by 1.46 t ha−1 (28%). Crop above-ground N-uptake at harvest on average was reduced from 16.2 kg N ha−1 under HN to 8.5 kg N ha−1 under LN conditions while N-utilization efficiency (grain DM yield per unit above-ground N uptake at harvest; NUtE) increased from 32.7 to 44.6 g DM g−1 N. Significant N × genotype level interaction was observed for GY, N uptake at harvest and NUtE. Overall genetic variability in GY and NUE (which ranged from 15.6 - 23.7 g DM g−1 N under LN; P<0.001) related mainly to differences in N uptake rather than NUtE. Overall, cultivars ranged significantly at anthesis in N accumulation in the flag-leaf N (1.1 -2.2 g N m−2 at HN and 0.5-1.0 g N m−2 at LN), the stem and remaining leaf with sheath (5.78-11.97 at HN and 3.61- 6.33 g N m−2 at LN) (P=0.01), and the ear (2.91-6.13 at HN and 2.06-4.23 g N m−2 at LN) (P<0.001). Cultivars ranged in N partitioning index (proportion of above-ground N in the crop component, NPI) at anthesis for the flag-leaf from 0.08 to 0.16 at HN and 0.07 to 0.13 at LN (P< 0.001); and for the stem-and remaining leaf with sheath from 0.54 to 0.68 at HN and from 0.52 to 0.65 at LN (P<0.001) and for ear from 0.21 to 0.34 at HN and from 0.28 to 0.41 at LN (P<0.001). The post-anthesis NRE was positively associated with the duration of flag-leaf senescence amongst cultivars under LN. Genetic variation in grain yield and grain N% (through N dilution effects) appeared to be mainly influenced by pre-anthesis N accumulation rather than post-anthesis N remobilization under LN conditions. Under N stress conditions, there was evidence that NRE was a determinant of genetic variation in grain N%. Flag-leaf Amax was positively associated with AGDM (P=0.02), GY (P=0.14), and specific leaf N at anthesis (P=0.046). Flag-leaf onset (VS.OnsetRP) and end (VS.EndRP) of senescence was positively associated with GY, AGDM and NRE in both N treatments. In the glasshouse experiments, out of 18 amphidiploid lines, two lines under HN and three lines under LN conditions showed transgressive segregation (TS) above the bread wheat parent for pre-anthesis Amax and 12 lines under HN and 7 lines under LN conditions showed TS for post-anthesis Amax. In addition, higher expression than the bread wheat parent was observed for Thinopyrum turcicum P208/201 x Chinese Spring Eup 94 under HN conditions for GY and for Thinopyrum turcicum P208/201 x Chinese Spring Eup 94, Secale anatolicum P208/142 x Highbury and Secale anatolicum P208/141 x Chinese Spring Eup 94 under HN conditions for AGDM showing potential to exploit these genotypes for wide crossing for NUE wheat breeding. Seedling root architectural traits including seminal root number per plant showed association with field and glasshouse GY and NUE related traits in HN and LN conditions. Overall amphidiploids showed evidence for increased root depth than bread wheat cultivars in the hydroponics seedling platform under both HN and LN conditions. In summary: • N-use efficiency in thirty Indian wheat cultivars in the field was correlated with onset of flag-leaf senescence under high N and low N conditions and senescence timing was correlated with N accumulation at anthesis. • Yield response to N limitation of 30 wheat cultivars was associated with responses in N uptake at anthesis under both N conditions. • The grain yield in N stressed crops for the 30 cultivars was limited by post-anthesis source capacity. • Three amphidiploids lines (Thinopyrum turcicum P208/201 x Chinese Spring Eup 94, Secale anatolicum P208/142 x Highbury and Secale anatolicum P208/141 x Chinese Spring Eup 94) in glasshouse conditions showed higher flag-leaf photosynthesis rate and prolonged flag leaf green area than their recurrent parents. • The 2D seedling RSAT study showed seminal root number was correlated amongst 12 Indian wheat cultivars and amphidiploids with grain yield per shoot under high and low N conditions.
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Wiesner, Emma. "Optimization and energy efficiency measures in modified combined heat and power plant processes : A case study of changed processes in Mälarenergi power plant." Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-324389.
Повний текст джерелаАнотація:
The EU energy efficiency directive is driving the EU member states to set ambitious goals to increase energy efficiency. Mälarenergi AB is one of the Swedish energy companies, affected by the directive, that have taken an active role in order to increase efficiency within their energy production. This study was initiated to perform energy analysis and find energy optimization measures in the systems attached to one of Mälarenergi’s CHP-units, called P5.The operating conditions of the bio fueled combined heat and power plant, P5, recently changed when the connected boiler, P4, was decided to be shut down. The two boilers shared turbine, steam, feed water, condensate and oil systems, and the operating conditions of these systems changed radically when the mass flow decreased as P4 was shut down. The changed operating conditions affects the efficiency and the performance of the plant. The changed mass flow affects the capacity demands, efficiency in components and the technical conditions of the plant.The general approach through this thesis and the used methodology is based on initial analysis of the system changes, review of the necessary functions in the system and identification of the differences between the needed functions and the existing system. Optimization potential were identified where there were large differences and as a final step, technical and economic feasibility of implementing identified optimization measures was analyzed. The results shows that feasible optimization potential is identified in removing pumps without adjustable speed drives from the system, installing adjustable speed drives to the warm condensate pumps, replacing the dilution water pumps and detaching the atomization steam tank for P4. The economic feasibility to invest in a new direct heater, better adjusted to the operating conditions of P5, is small but could be an option to Mälarenergi if the alternative production cost remains high. Without the already installed adjustable speed drives in Mälarenergi’s plant the efficiency of the operations would be much lower than what it is today and the optimization potential essentially larger. The efficiency potential in the plant increases further when the attached turbine, G4, is to be dismantled and the operating conditions changes again. More extensive simplifications and rearrangements of the system can be made to decrease the energy demand for operations with 745 MWh/year.EU:s energieffektiviserings direktiv ställer hårda krav på företag i medlemsländerna att kartlägga och analysera energiförbrukning för att identifiera åtgärder för att öka effektivitet. Utöver detta så har Sverige ambitiösa mål om ökad energieffektivitet i samtliga sektorer. Att effektivisera energiproduktionsanläggningar för att hitta effektiviseringspotential är därför aktuellt för svenska energiproducenter. Mälarenergi är ett av de energiföretag som arbetar aktivt med att kartlägga och minska sin energiförbrukning. Studien har därför genomförts för att granska panna 5 i Västerås kraftvärmeverk, för att undersöka hur energieffektiviseringsåtgärder kan identifieras i kraftvärmeprocesser där driftförutsättningar och processer har förändrats. Panna 5 har flertalet gemensamma processer med en äldre panna i anläggningen, panna 4, vars drift har upphört och pannan ska läggas ner. Driftförhållandena i de tidigare gemensamma systemen för kondensat, matarvatten, kylning och olja har därför förändrats och massflöden i systemen minskat kraftigt. De förändrade förhållandena och massflödena påverkar kapacitetsbehovet i systemen, effektiviteten i flertalet komponenter samt de tekniska kraven som ställs på panna 5. Den största förändringen i systemet är de minskade massflödena. Flödet i kondensatsystemet har minskat från ca 100 kg/s till 45 kg/s. Samma förändring i matarvattensystemet då panna 4 kopplas bort, är från 160 kg/s till 50 kg/s. Studien visar att det finns energieffektiviseringspotential i att byta ut pumpar vars pumpdrift har påverkats kraftigt, upphöra med drift av pumpar utan frekvensstyrning, installera frekvensstyrning på pumpar där flöden varierar samt förenkla och ta bort överflödiga processer som inte nyttjas vid de nya förhållandena. Processerna kan också optimeras genom att investera i en ny direktvärmare bättre lämpad för panna 5, dock är lönsamhetskalkylen för denna svag och ytterligare bedömning krävs. Resultatet visar även att då turbinen till panna 5 är uttjänt och nedmonteras så kan processerna kring panna 5 förenklas ytterligare och optimeras så pass att 745 MWh el för drift av pannan kan sparas varje år. Generellt kan det konstaterats att även förvärmare, matarvattentank och värmeväxlare är överdimensionerade när flödet i systemet minskar, kostnads-och energibesparingen för att byta ut dessa komponenter är dock negativa, eftersom komponenterna själva inte förbrukar någon energi. Att ha för stora kapaciteter i värmeväxlare bör snarare ses som en möjlighet, att kartlägga kapacitetsbehovet underlättar dock underhållsplanering i systemet. Den generella metoden som användes i studien bygger på modellen att först kartlägga de genomförda förändringarna i systemen, fastställa funktionskraven i det nya systemet och därefter analyserna skillnaderna mellan de fastställda funktionskraven och den befintliga tekniken. Optimeringspotential kan därefter identifieras där dessa två skiljer sig till stor del. Därefter utvärderas optimeringsåtgärden genom kvantitativ analys och investeringskalkylering.
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White, Charlotte Anne. "Increasing the water use efficiency (WUE) of tomato (S. lycopersicum) via manipulation of the abscisic acid (ABA) biosynthesis pathway." Thesis, University of Nottingham, 2011. http://eprints.nottingham.ac.uk/11948/.
Повний текст джерелаАнотація:
Breeding plants that produce equivalent growth with reduced water input (improved water use efficiency (WUE)) is necessary for sustained future crop production. Water deficit induces redistribution and synthesis of the phytohormone abscisic acid (ABA) thereby restricting transpiration. ABA is synthesised via cleavage of oxygenated carotenoids (xanthophylls). This work involved two approaches and three key ratelimiting enzymes in the ABA biosynthesis pathway: 9-cis-epoxycarotenoid dioxygenase (NCED) β-carotene hydroxylase (BCH); and phytoene synthase (PSY). Increasing ABA production under optimal conditions by overexpressing SlNCED1 has been shown to reduce stomatal conductance and improve WUE. The first approach, part of a larger programme exploring the allelic variation of NCED1 in wild tomato species, describes the introgression of S. galapagense and S. neorickii NCED1 alleles into the cultivated tomato background S. lycopersicum cv. Ailsa Craig. Plants homozygous for SgNCED1, SnNCED1 and SlNCED1 alleles were compared for water use gravimetrically. It was concluded that SgNCED1 and SnNCED1 did not improve WUE. The second approach involved creating a transgenic rootstock that might provide sufficient extra root-sourced ABA under non-stressed conditions to improve WUE of a non-transgenic scion. Root tissues contain less carotenoids than photosynthetic tissues, which may limit increases in root ABA biosynthesis. To increase precursor flux through the pathway, transgenic lines simultaneously over-expressing SlPSY1, SlBCH2, and SlNCED1 were created by crossing two double transgenic lines. Isolated roots of a selected triple line (H-22-8-8) accumulated increased concentrations of carotenoids, ABA and ABA catabolites. Gravimetric water use trials revealed that WT/H-22-8-8 (scion/rootstock) grafts frequently showed improved; TEp, δ13C, exudate flow rate and ABA concentration. H-22-8-8 rootstock conferred a consistent, modest, daily water saving; significant in the absence of water stress. This indicates that the triple rootstock is capable of restricting stomatal opening and water use, without reducing biomass production.
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Amamou, Ali. "Identifying novel variation in grain yield, biomass and N-use efficiency and its physiological and genetic basis in wheat." Thesis, University of Nottingham, 2015. http://eprints.nottingham.ac.uk/44030/.
Повний текст джерелаАнотація:
Wheat (Triticum aestivum L) is the most widely grown crop in the world and accounts for approximately 31% of global cereal consumption every year (FAO, 2012). Furthermore, wheat is the most traded product worldwide (Dixon et al. 2009). In UK, wheat is the largest arable crop, it is grown on about 1.8 M ha p.a. For wheat productivity and grain quality, nitrogen (N) is the most important fertilizer applied, and modern wheat culitvars are generally selected under high N supply. However, N fertilizer represents a significant cost of production and may have negative environmental impacts. N-use efficiency (grain DM yield / soil and fertilizer N available; NUE) can be divided into two main components: N-uptake efficiency (N uptake / soil and fertilizer N available; NUPE) and N-utilization. efficiency (grain DM yield / NUP; NUTE). The current study aims to identify novel variation for grain yield, above-ground dry matter (AGDM). NUE and NUE components in a panel of AE Watkins landraces compared to UK check cultivars in the glasshouse and field trials and in two Single Seed Descent (SSD) populations derived from the crosses between UK spring wheat Paragon and Watkins landrace line 481 (PxW481) and between Paragon and Watkins landrace line 141 (PxW141) in field experiments and to investigate the physiological and genetic bases of this variation. Two glasshouse experiments (2011/12 and 2012/13) examining 17 genotypes (comprising five UK check cultivars and 12 Watkins landraces), and one field experiment (2011/12) examining a panel of 10 genotypes (comprising three UK cultivars and seven of the 12 Watkins landraces examined in the field) were carried out. In addition, three field experiments examining two SSD populations PxW481 (79 lines) (in 2011/12 and 2012/13) and PxW141 (97 lines) (in 2012/13) under two N treatments (HN=200 kg N/ha and LN=0 kg N/ha) were carried out. The glasshouse experiments were located at the University of Nottingham, School of Biosciences, Sutton Bonington Campus, UK and field experiments were located at the University of Nottingham experimental station at Bunny Park, Nottinghamshire, UK. The genetic maps were presently constructed using 201 and 491 markers, including single nucleotide polymorphism (SNPs) and microsatellites (SSR) for PxW481 and PxW141, respectively. Grain yield (GY), yield components, AGDM, NUPE, NUTE, and physiological traits including leaf light-saturated photosynthesis rate (Amax), flag leaf chlorophyll content (SPAD) and the spectral reflectance index, Normalized Difference Vegetation Index (NDVI, indicative of canopy size, field experiments only) were measured in the experiments. Genetic variation in grain yield was more closely associated with AGDM than with harvest index (HI) in the glasshouse and in the field under both HN and LN. For biomass production, the results showed that Paragon, Rialto, Xi19 and landrace W141 had higher AGDM than all other genotypes. In summary, UK check cultivars generally had higher grain yield (GY) compared to Watkins landraces and higher AGDM in the glasshouse under HN conditions. Similar results were found in the field under HN; however, under LN, the majority of Watkins lines maintained GY and AGDM than the UK cultivars compared to HN conditions. With regard to N uptake at harvest, the Watkins landraces W040, W141 and W579 had similar NUP to Paragon and higher than Oakley in the glasshouse. In the field, in general, Watkins lines maintained relatively better NUPE under LN than the UK check cultivars. A negative association amongst genotypes was found between NUTE and grain N concentration (%) in the glasshouse and in the field under HN and LN treatments, with the strongest association observed under LN conditions. Variation for light-saturated leaf photosynthesis rate (Amax) was also observed amongst Watkins lines. In the glasshouse experiments, the UK cultivars, and landraces W141 and W352, generally had higher pre-anthesis Amax than other Watkins landrace lines. In the field experiment, landrace lines W352 and W141 had higher pre-anthesis Amax than Paragon under LN, whereas lines, W223 and W034 had higher values under HN. Genetic variation in GY and AGDM were overall better associated with post-athesis flag-leaf Amax than with pre-anthesis flag-leaf Amax in the field, and the associations with post-anthesis Amax tended to be stronger under HN rather than under LN conditions. With regard to the two SSD mapping populations, both N and genotype had a significant effect on GY, AGDM, NUPE and NUTE for PxW481 in all three experiments. For the PxW481 population, no SSD line had either higher GY or AGDM than Paragon under HN, while under LN, 13 lines had higher GY and two lines had higher AGDM than Paragon (P < 0.05). For the PxW141 population, three lines had higher grain yield under HN and three lines had higher GY under LN than Paragon. Five and 10 SSD lines under HN and LN, respectively, had higher AGDM than Paragon. The transgressive segregation for GY was due to either AGDM or HI, depending on the line. In both populations under both N treatments, genetic variation in NUE was more strongly associated with NUPE than with NUTE under HN and LN; however, the response of NUE to N availability was better associated with NUTE. Averaging years for the PxW481 population under HN, no SSD line had higher NUPE than Paragon, while under LN L481-76 had higher NUPE than Paragon. For PxW141, no SSD line had higher NUPE than Paragon either under HN or under LN conditions. Seventeen SSD lines of the PxW481 population had significantly higher NUTE than Paragon under HN and 10 lines higher under LN conditions. For PxW141 under HN, L141-95 and L141-94 had higher NUTE than Paragon under HN, while under LN 12 SSD lines had higher values. In both the PxW481 and PxW141 populations, genotype and N treatment had an effect on NDVI (canopy size) for all measurements pre and post-anthesis. Genetic variation in yield, biomass and NUPE were more closely associated with NDVI measured at around anthesis than at other measurement dates. In addition, the correlation amongst genotypes was stronger under LN than under HN conditions. Genetic variation for flag-leaf senescence parameters was also found in both mapping populations, and association with grain yield amongst genotypes was stronger under LN conditions than under HN conditions in both populations. QTL analysis identified two major QTLs for grain yield on 6AL and 5A under HN and one major QTL on 2B under LN conditions in the PxW481 population. The QTL on 6AL co-located with a QTL for NUPE, while the one on 5A co-located with a putative QTL for AGDM. Simonds et al. (2014) reported a major stable QTL in the same region of 6AL in the Spark x Rialto DH population across several environments. Under LN conditions, the QTL on 2B co-located with a QTL for plant height. For AGDM, a major QTL under both HN and LN was identified on chr 4B in the PxW481 population. This QTL co-located with a QTL for NUPE under both HN and LN conditions. In addition, a major QTL under HN for NUPE on 3BL (PxW481) co-located with QTLs for GY and AGDM. Another major QTL on 2A (PxW141), co-located with flag-leaf stay-green traits. This is consistent with the findings of Bogard et al. (2011) who reported two QTLs for NUPE under LN on 2A, associated with a delay in onset of flag-leaf senescence. With regard to NUTE, two major QTLs on 3B, co-locating with QTL for GY and HI, and on 1B, co-locating with a QTL for N grain concentration, were found for the PxW481 population under LN. In addition, three QTLs on 3A, co-locating with a QTL for TGW, and on 6D and on 7B, co-locating with QTLs for TGW, were identified.
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Kakkar, Avneet. "Nitrogen Availability and Use Efficiency in Corn Treated with Contrasting Nitrogen Sources." DigitalCommons@USU, 2017. https://digitalcommons.usu.edu/etd/6886.
Повний текст джерелаАнотація:
The plant-soil nitrogen cycle plays a significant role in allocation of available N to plants, and improved understanding of N cycling helps sustainably increase fertilizer use efficiency. There are various processes (nitrogen mineralization and nitrification) involved in the availability and mobility of nitrogen in the soil. The primary objective of this study was to determine the NUE under contrasting nitrogen treatments over a period of five years. Additionally, we examined the effect of different N treatments on N mineralization and nitrification in conventional and organic farming systems.
This project was funded by Agriculture and Food Research Initiative Competitive Grants Program Grant no. 2011-67019-30178 from the USDA National Institute of Food and Agriculture and by the Utah Agricultural Experiment Station. We established silage corn field plots in northern Utah, and silage corn was grown using ammonium fertilizers or manure composts over five years. Nitrogen use efficiency was found to be higher in ammonium sulfate fertilizer treatments as compared to compost treated soils. Nitrogen mineralization and nitrification rates were examined for soils from the silage corn field plots and also for additional soils from certified organic field plots receiving steer compost, steer manure and crop rotations. There was a significant overall nitrogen treatment effect for both conventional and organic rotational plots. Carbon mineralization rates were found to be higher in compost under conventional plots and manure under organic rotational plots as compared to control. There was no significant treatment effect found in gross mineralization and nitrification rates in 2015 and 2016. Gross nitrification rates were found to be the higher in AS200 treatment versus compost and control in 2016.
Improved knowledge of the timing and rates of nitrogen supply is vital for improving NUE and for reducing excessive use of fertilizers while maintaining an acceptable yield. The optimization of fertilizer rates according to crop demand at different stages of growth will be helpful in the efficient management of available N especially for composts and manures.
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Loftus, Wynand Johan. "Strategic adaptive management and the efficiency of invasive alien plant management in South African national parks." Thesis, Nelson Mandela Metropolitan University, 2013. http://hdl.handle.net/10948/d1020089.
Повний текст джерелаАнотація:
It is well known that invasive alien plants (IAPs) pose a significant threat to natural biodiversity and human well-being. Through various pressures exerted on natural ecosystems, IAPs decrease and alter natural processes that provide important ecosystems services and livelihoods to human communities. These plants also displace and out-compete natural plant communities in the areas in which they invade. Management of IAPs is a complex issue with social, environmental and financial challenges. The long-term sustainable management of IAPs requires a management approach that monitors and measures the outcomes of current management practices, and considers the lessons learnt in future decision making. Adaptive management is such an approach and is characterised by monitoring, assessment, reflection and adaptation. In this dissertation I explore IAP management within the South African National Parks (SANParks) organisation. I focus on the quality of the available IAP clearing data for monitoring and environmental decision-making and explore how strategic adaptive management (SAM) is being applied to IAP management. Strategic adaptive management is a form of adaptive management that SANParks adopted to deal with the inherent unpredictability of the social ecological systems they manage, and is primarily a learning-by-doing approach. In chapter one I describe the various impacts that IAPs have on natural environments. I also discuss management of IAPs, the national Working for Water (WfW) programme and how SANParks control IAPs in partnership with WfW. Clearing of IAPs within the borders of SANParks is funded by the Department of Environmental Affairs‘ (DEA) Natural Resource Management programmes and carried out through the Working for Water programme, under SANParks‘ Biodiversity Social Projects programme and is done on a contract basis. Contract data are stored in the Working for Water Information Management System (WIMS) database. Although IAP clearing is well established, the efficiency of overall clearing operations within the parks, and quality and reliability of the data available in the WIMS, needs to be examined. In Chapter two, I (i) assess the status of IAP clearing and the direct clearing costs in each of the five national parks (costs are inflated to 2012 equivalents using the consumer price index), (ii) assess the accuracy of workload estimations for WfW IAP clearing, and (iii) discuss the utility of WIMS as a system to collate and store accurate data for monitoring purposes, focusing on the integrity and reliability of the data, the accuracy of density estimations and whether it can inform sound decision making. The planning of future clearing contracts lacks efficiency due to inaccuracies and unreliability of input data, specifically estimates of invasive alien plant density. The accuracy of density estimation and cost of clearing varies greatly between parks and does not appear to reflect the reality on the ground. In Chapter 3, through an interview process with IAP managers, I 1) unpack the steps in the SAM ‗cycle‘ and investigate the effectiveness of implementation of each step according to respondents; 2) assess the barriers that are currently keeping managers from implementing effective IAP management; 3) discuss whether learning and adaptation is taking place, and 4) discuss how the SAM process can be modified to promote its effectiveness.
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Smith, Ian A. "The effects of two foraging traits on within-plant foraging efficiency of Phytoseiulus persimilis (Acari: phytoseiidae)." Thesis, Kansas State University, 2011. http://hdl.handle.net/2097/8632.
Повний текст джерелаАнотація:
Master of ScienceDepartment of Entomology
David C. Margolies
James R. Nechols
Many crops grown in greenhouses are damaged by the twospotted spider mite, Tetranychus urticae. The predatory mite, Phytoseiulus persimilis, is a commercially-available predator that is commonly used to control twospotted spider mites on greenhouse crops; but its efficacy varies among crops, and it is generally ineffective at low prey densities. In general, predator foraging efficiency depends on how well predators find prey patches, the length of stay in prey patches, and consumption of prey while in prey patches. With respect to P. persimilis, I asked how this predator responds to different prey distributions, as might be encountered at different stages of spider mite infestations. I also asked how components of foraging, namely consumption rate and dispersal tendency, affected predator efficiency. To examine the former, I established T. urticae eggs on 6-leafed cucumber plants in two distributions. To examine the latter, I imposed artificial selection on a population of P. persimilis to create a line that exhibited extremely high consumption and one that demonstrated a greater tendency for dispersal. Subsequently, foraging efficiency was assessed by observing predator oviposition and consumption of twospotted mite eggs on individual leaves of 6-leafed cucumber plants. The number of eggs laid by predators corresponded to the number of prey consumed regardless of predator line. In addition, predators from both lines distributed their eggs proportional to where they fed. However, prey consumption differed between selected lines in response to prey distribution. Predators selected for high consumption fed more on the basal leaf where they were released; whereas prey consumption by the high dispersal and control lines were more evenly distributed throughout the plant. These results contribute to a better understanding of how foraging behavior is modified in plant landscapes under different levels of expression of foraging traits. They also indicate that predator release strategies likely would need to modified in accordance with the kind of foraging trait(s) used in artificial selection programs. In general, my research, when combined with future studies at a broader landscape level, will facilitate decisions by biological control practitioners about whether changes in foraging efficiency resulting from artificial selection justify the cost investment of producing selected lines of P. persimilis
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Kroll, Douglas M. "Using polymer electrolyte membrane fuel cells in a hybrid surface ship propulsion plant to increase fuel efficiency." Thesis, Cambridge Massachusetts Institute of Technology, 2010. http://hdl.handle.net/10945/4941.
Повний текст джерелаАнотація:
CIVINSApproved for public release; distribution is unlimited
An increasingly mobile US Navy surface fleet and oil price uncertainty contrast with the Navy's desire to lower the amount of money spent purchasing fuel. Operational restrictions limiting fuel use are temporary and cannot be dependably relied upon. Long term technical research toward improving fuel efficiency is ongoing and includes advanced gas turbines and integrated electric propulsion plants, but these will not be implemented fleet wide in the near future. The focus of this research is to determine if a hybrid fuel cell and gas turbine propulsion plant outweigh the potential ship design disadvantages of physically implementing the system. Based on the potential fuel savings available, the impact on surface ship architecture will be determined by modeling the hybrid fuel cell powered ship and conducting a side by side comparison to one traditionally powered. Another concern that this solution addresses is the trend in the commercial shipping industry of designing more cleanly running propulsion plants.
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Kroll, Douglas M. (Douglas Michael). "Using polymer electrolyte membrane fuel cells in a hybrid surface ship propulsion plant to increase fuel efficiency." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/61909.
Повний текст джерелаАнотація:
Thesis (Nav. E.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering; and, (S.M. in Engineering and Management)--Massachusetts Institute of Technology, Engineering Systems Division, System Design and Management Program, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 59).
An increasingly mobile US Navy surface fleet and oil price uncertainty contrast with the Navy's desire to lower the amount of money spent purchasing fuel. Operational restrictions limiting fuel use are temporary and cannot be dependably relied upon. Long term technical research toward improving fuel efficiency is ongoing and includes advanced gas turbines and integrated electric propulsion plants, but these will not be implemented fleet wide in the near future. The focus of this research is to determine if a hybrid fuel cell and gas turbine propulsion plant outweigh the potential ship design disadvantages of physically implementing the system. Based on the potential fuel savings available, the impact on surface ship architecture will be determined by modeling the hybrid fuel cell powered ship and conducting a side by side comparison to one traditionally powered. Another concern that this solution addresses is the trend in the commercial shipping industry of designing more cleanly running propulsion plants.
Douglas M. Kroll.
S.M.in Engineering and Management
Nav.E.
44
Gilmore, Scott R. "Genetic mapping of plant transpiration efficiency." Phd thesis, 2005. http://hdl.handle.net/1885/149993.
Повний текст джерела
45
Cheng, Sung-Yin, and 鄭淞尹. "Increase efficiency of Agrobacterium-mediated plant transformation." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/72455419769649438016.
Повний текст джерелаАнотація:
碩士國立中興大學
生物科技學研究所
102
Agrobacterium-mediated T-DNA transfer is well-known to be a powerful plant transformation tool. This method mostly confers single or low-copy integration of full-length gene, and leads to less problems in gene-silencing. But, a lot of important crops are still “recalcitrant” to transformation. Thus, it is still important to improve the plant transformation efficiency using Agrobacterium-mediated method. The long journey for T-DNA transferring from bacteria till the final destination requires bacterial proteins and various plant factors. As co-transformation of T-DNAs carrying GUS/hyg and rice H2A genes, respectively, often cause co-integration of the H2A gene in absence of selection marker, we were interested to investigate its mechanism. A single nucleotide change leads to nonsense mutation (H2Am) was constructed. The high co-integration frequency of H2A gene will be clarified to be caused by DNA itself or the encoded protein. In this study, the H2A and H2Am both have no high co-integration frequency, this result is different with previous studies. In addition, we found the rice H2A is not significant high co-integration frequency in Arabidopsis. So, we will test Arabidopsis H2A Group I can enhance co-integration frequency in Arabidopsis or not. In these experiment the Arabidopsis H2A is not significant high co-integration frequency. Moreover, AvrPto is an effector protein that suppresses plant immunity. Expression of AvrPto in Arabidopsis dramatically enhances its transient transformation efficiency mediated by Agrobacterium. VirB5 is an essential virulence (Vir) protein and represents a minor component of the T-pilus. Besides, VirB5 is translocated to the physical interface between bacterial and plant cell surface, suggests an additional role of VirB5 involving early interactions between Agrobacterium and the host cell. Using co transformation of T-DNAs carrying GUS/hyg and AvrPto genes, respectively, transient transformation efficiency of GUS was found to be ~1.3-fold higher than control experiment. Other experiments we examine that addition of purified VirB5 proteins when infected rice callus. we found the VirB5 proteins is not significant high transformation rate in rice.
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Hlalele, Thabo Gregory. "Optimal metering plan in an energy efficiency project for a ferrochrome plant." Diss., 2014. http://hdl.handle.net/2263/43351.
Повний текст джерелаАнотація:
An accurate measurement of retrofitted loads is essential for the quantification of energy
savings in an energy conservation measure project. This research presents an optimal meter
placement approach to an ECM project in a ferrochrome plant. The ECM project is implemented
in a selected plant in a ferrochrome production line in which three different types of
loads are considered for retrofitting.
The aim of this research is to minimize the metering costs associated with the measurement
and verification process while satisfying the precision and accuracy requirements for
the sampling and measurement plan. The metering costs are reduced by using two types
of metering devices. One meter yields highly accurate data measurements, has superior
functionality to the other meter and is consequently highly priced. Different sampling requirements
for the ECM project are evaluated and an optimal solution is found by selecting a
combination of inexpensive and expensive metering equipment. The proposed optimal meter
placement configuration yields a combination of meters with the highest accuracy in the ECM
and has the lowest cost.Dissertation (MEng)--University of Pretoria, 2014.
lk2014
Electrical, Electronic and Computer Engineering
MEng
Unrestricted
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Milla, Odette Marie Varela, and 歐蒂娣. "Preparation and Plant-growth Efficiency Assessment of Biochars." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/23229324041750065088.
Повний текст джерелаАнотація:
博士國立屏東科技大學
熱帶農業暨國際合作系
101
Biochar is charcoal made from organic matters such as plant biomass and agricultural wastes that can be used to increase soil ability to sequester carbon and simultaneously improve its nutrient contents and water retention. Biochar can aid in nutrient retention and cation exchange capacity, decreasing soil acidity, decreased uptake of soil toxins, improving soil structure, nutrient use efficiency, water-holding capacity, and decreased release of non-CO2 greenhouse gases. There is great potential for biochar production and application to have positive outcomes through carbon sequestration, and improved soil health. Few researches in biochar classifications have been done. The aims of this study is to generate biochars from organic wastes, to analyze their concept and origins, to investigate their key roles on agriculture planting, to study the effect of production process, on the plant germination rate and their potential uses with other industrial solid wastes, such as bottom ash. The major founds in this thesis are as follow: Extraction of polyphenols from a municipal solid waste incineration (MSWI) bottom ash mixed matrix and Zea mays L. dry biomass. Polyphenol content was shown to increase when fertilizer was applied, presenting inhibition to plant growth, root yield and plant biomass dry weight. After fertilizer application, the polyphenol content increased between 45-55 mg/L. Without the fertilizer, the polyphenol content was 5-25 mg/L. In addition, the used bottom ash (BA) enhanced biochar degradation; this process could be achieved through our results. Results from studies made on the mixture of bamboo biochar and rice husk biochar with municipal solid waste incineration bottom ash let us conclude that the mixture of these components has a positive effect on the development and early growth of corn (Zea mays L.). The treatment that showed the best results in this test without a concern about the leaching of heavy metals lead (Pb) and cooper (Cu) was rice husk. This treatment was pyrolized at 400ºC and combined with Pingtung MSWI bottom ash, with and without additions of fertilizer; the treatments showed the best results in germination (100%) and plant weight. With regards of the results, detailing the growth of water spinach, they showed that the application of rice husk biochar improves biomass production. The wood biochar added to soil increased the plant weight of water spinach by increasing the root size and leaf width, whereas rice husk biochar added to soil increased plant weight by increasing the stem size and leaf length of the water spinach. In addition, the stem size of water spinach was proportional to the ratio of water-holding capacity to silt content in soil; whereas the root size of water spinach was proportional to the organic matter/organic carbon ratio of soil. Moreover, rice husk biochar process produces high silicon content, and its application in soil induces dissolvable silicon in soil that plays a chelator role in transporting water and trace elements from the soil matrix to the plant. Rice husk biochar application affects significantly the corn seeds germination and improves the plants growth rate due to the high silicon (Si) content found. In addition, the silicon was found to have a critical threshold when its content in the rice husk biochar is higher than 20%, which is a sufficient level to be harmful for corn seed germination. The use of bamboo is a smart option for those industries that want to transform biochar into a profit without harming any ecosystem. The main objectives of this study are to investigate the potential capability of bamboo biochar to affect germination and growth of edible crops. In conclusion, the four temperatures (240ºC, 300ºC, 600ºC and 700ºC) of bamboo biochars used in this study generally increased wheat seed germination at rates of application of 50% for 240ºC and 300ºC biochars; while 600ºC and 700ºC biochars tended to inhibit germination at the highest rate of application (100%) under the bioassay conditions. This study demonstrated the potential of biochar as an amendment of clayey soils. Our findings suggest that an application rate of 10 t ha-1 should not be exceeded when applying biochar on these soils.
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Eid, Ayman. "High-efficiency plant genome engineering via CRISPR/Cas9 system." Diss., 2019. http://hdl.handle.net/10754/632513.
Повний текст джерелаАнотація:
Precise engineering of genomes holds great promise to advance our understanding of gene function and biotechnological applications. DNA double strand breaks are repaired via imprecise non-homologous end joining repair or via precise homology-directed repair processes. Therefore, we could harness the DSBs to engineer the genomes with a variety of genetic outcomes and with singlebase- level precision. The major barrier for genome engineering was the generation of site-specific DNA DSBs. Programmable DNA enzymes capable of making a complete and site-specific cut in the genome do not exist in nature. However, these enzymes can be made in in vitro as chimeric fusions of two modules, a DNA binding module and a DNA cleaving module. The DNA cleaving module can be programmed to bind to any user-defined sequence and the DNA cleaving module would generate DSBs in the target sequence. These enzymes called molecular scissors include zinc finger nucleases (ZFNs) and transcriptional activator like effector nucleases (TALENs). The programmability of these enzymes depends on protein engineering for DNA binding specificity which may be complicated, recourse intensive and suffer from reproducibility issues.
Recently, clustered regularly interspaced palindromic repeats (CRISPR)/ CRISPR associated endonuclease 9 (Cas9) an adaptive immune system of bacterial and archaeal species has been developed for genome engineering applications. CRISPR/Cas9 is an RNA-guided DNA endonuclease and can be reprogrammed through the engineering of single guide RNA molecule (sgRNA). CRISPR/Cas9 activity has been shown across eukaryotic species including plants. Although the engineering of CRISPR/Cas9 is quite predictable and reproducible, there are many technological challenges and improvements that need to be made to achieve robust, specific, and efficient plant genome engineering. Here in this thesis, I developed a number of technologies to improve specificity, delivery and expression and heritability of CRISRP/Cas9-modification in planta. Moreover, I used these technologies to answer basic questions to understand the molecular underpinning of the interplay between splicing and abiotic stress.
To improve Cas9 specificity, I designed and constructed a chimeric fusion between catalytically dead Cas9 (dCas9) and FOKI catalytic DNA cleaving domain (dCas9.FoKI). This synthetic chimeric fusion enzyme improved Cas9 specificity which enable precision genome engineering. Delivery of genome engineering reagents into plant cells is quite challenging, I developed a virus-based system to deliver sgRNAs into plants which facilitates plant genome engineering and could bypass the need for tissue culture in engineering plant genomes. To improve the expression of the CRISPR/Cas9 machinery in plant species, I developed a meiotically-driven expression of CRISPR/Cas9 which improved genome editing and heritability of editing in seed progeny, thereby facilitating robust genome engineering applications.
To understand the molecular basis of the interplay between splicing stress and abiotic stress, I used the CRISPR/Cas9 machinery to engineer components of the U2snRNP complex coupled which chemical genomics to understand the splicing stress regulation in response to abiotic stress conditions. Finally, I harnessed the technological improvements and developments I have achieved with CRISPR/Cas9 system to develop a directed evolution platform for targeted trait engineering which expands and accelerates trait discovery and engineering of plant species resilient to climate change conditions.
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Jian, Dong-Zhao, and 簡東照. "An Empirical Study of Plant Efficiency and Cost Analysis ─An Case Study for Military Repair Plant." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/20043189182913687812.
Повний текст джерелаАнотація:
碩士國防管理學院
資源管理研究所
87
The purposes of this study are to evaluate the efficiency of a military repair plant and to find the effectiveness factors on its manufacturing overhead. This study employs the Data Envelopment Analysis (DEA) model to evaluate the different in efficiency between two repair lines in this plant. Also, we use the Slack Variable Method to analyze the usefulness of various inputs. Furthermore, the Activity Based Cost System (ABC) was employed to explore the cost drivers which affect its manufacturing overhead. The results of this study can be applyed to improve the efficiency of operations and enhance cost controls.
50
Chou, Chih-Hung, and 周志鴻. "The Impact Factors of Thermal Efficiency of Taipower's Fossil Fuel Power Plant : Taichung Thermal Power Plant." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/89408865349209564065.
Повний текст джерелаАнотація:
碩士國立交通大學
管理學院碩士在職專班經營管理組
97
The coal-fired power plants provide over 30% of the capacity of Taipower. Effectively enhancimg the efficiency of power plants can help reduce both the cost of power generation and the greenhouse gas emissions. In this research we collect and analyze the operational data of coal-fired steam turbine power units No.1~No.8 of Taichung Power Plant, in order to establish a multiple regression model of thermal efficiency. This research provides suggestions for Taipower company to improve its thermal efficiency. Our major empirical findings are: (1) The temperature of main steam, re-heat steam pressure drop and pressure of main steam significantly increase the thermal efficiency. (2) The temperature of the air inlet, temparture of the water inlet, in-plant electricity usage, re-heat steam temperature and exhaust pressure significantly worsen the thermal efficiency. Therefore, the Taipower caompany should select appropriate locations of fire-power plants, keep lodaings at the rated levels, reduce generation-irrelevant in-plant electricity usage, promote trainings of operating personnel, and improve the functions of boliers, etc., in order to enhance its thermal efficiency.