Journal articles on the topic 'Internal nitrogen use efficiency'
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1
Robinson, Nicole, Andrew Fletcher, Alex Whan, Christa Critchley, Nicolaus von Wirén, Prakash Lakshmanan, and Susanne Schmidt. "Sugarcane genotypes differ in internal nitrogen use efficiency." Functional Plant Biology 34, no. 12 (2007): 1122. http://dx.doi.org/10.1071/fp07183.
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The large amounts of nitrogen (N) fertiliser applied to most cropping systems support high yields but cause N pollution. More efficient use of N in cropping systems can be achieved through improved N management practices combined with genetic improvement of the crop. The magnitude of genetic variation in sugarcane (Saccharum officinarum L.) for internal nitrogen use efficiency (iNUE, biomass produced per unit tissue N) was investigated as this could provide a basis for breeding varieties with reduced N demand. Genotypes of a mapping population were examined for biomass production and physiological variables under low or high N supply in controlled conditions. Key findings were: (i) genotypic variation for biomass production and iNUE was up to 3-fold greater under low than high N supply, (ii) elite parent Q165 was among the best performing genotypes for biomass and iNUE at high N but not at low N supply, and (iii) several genotypes had high iNUE at both N supplies. While glutamine synthetase (GS; EC 6.3.1.2) activity has been linked with grain yield in other crops, no direct relationship was observed between whole tissue GS activity and vegetative biomass or iNUE in sugarcane genotypes. Soluble protein content was negatively correlated with iNUE and biomass production. This study demonstrates that there is considerable genetic variation for iNUE in sugarcane, which can be exploited for breeding. It is proposed that breeding programs should assess genotypes not only at high N, but also at low N supply rates to select genotypes that produce high biomass with low and high N supply.
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Rose, Terry, Tobias Kretzschmar, Daniel L. E. Waters, Jeanette Balindong, and Matthias Wissuwa. "Prospects for Genetic Improvement in Internal Nitrogen Use Efficiency in Rice." Agronomy 7, no. 4 (October 30, 2017): 70. http://dx.doi.org/10.3390/agronomy7040070.
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Rochester, Ian J. "Assessing internal crop nitrogen use efficiency in high-yielding irrigated cotton." Nutrient Cycling in Agroecosystems 90, no. 1 (December 29, 2010): 147–56. http://dx.doi.org/10.1007/s10705-010-9418-9.
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Bronson, Kevin F. "Optimal internal nitrogen use efficiency for irrigated cotton in the southwestern United States." Agronomy Journal 113, no. 3 (May 2021): 2821–31. http://dx.doi.org/10.1002/agj2.20674.
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Brauer, Elizabeth K., and Barry J. Shelp. "Nitrogen use efficiency: re-consideration of the bioengineering approach." Botany 88, no. 2 (February 2010): 103–9. http://dx.doi.org/10.1139/b09-111.
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There is considerable confusion about N use efficiency (NUE) in the plant literature. We would like to propose the simple and ubiquitous definitions described by Good et al. (2004) as a starting point for studies of NUE. Based on this terminology, there is evidence from breeding programs for variation in both uptake efficiency (UpE) and utilization efficiency (UtE). Molecular physiology studies typically address mechanisms for improving NUE, but often do not calculate NUE or even acquire appropriate data for calculating NUE. Herein, we report in detail on recent studies involving molecular approaches for improving NUE, and calculate changes in NUE where possible. The evidence suggests that there is potential for improving usage index and UpE in dicots and UpE and UtE in monocots by overexpressing enzymes for N assimilation, specifically glutamine synthetase 1, glutamate synthase, and alanine aminotransferase. If decreased fertilizer-N input and improved NUE are truly goals of the plant biology community, researchers are encouraged to (i) consider the use of both wild type and azygous controls, (ii) compare general NUE (on the basis of grain or biomass yield per unit of applied N) of overexpression mutants and controls at both limiting and non-limiting N levels, (iii) select an appropriate type of specific NUE for assessing the physiological mechanisms involved (uptake versus internal utilization), and (iv) confirm promising results under field conditions.
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Tao, Zui, Yu Liu, Jiana Chen, Fangbo Cao, and Min Huang. "Yield Attributes Response to Nitrogen Fertilization in Low-Nitrogen Tolerant Hybrid Rice." Agronomy 12, no. 10 (September 27, 2022): 2320. http://dx.doi.org/10.3390/agronomy12102320.
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The development of low-nitrogen (N) tolerant varieties is an effective way to improve the use efficiency of N in rice and is crucial to the sustainable rice production in China. Recently, we observed that higher grain yields were obtained in the hybrid rice variety Deyou 4727 (DY4727) than in the hybrid rice variety Y-liangyou 900 (YLY900) under zero-N fertilization conditions, suggesting that DY4727 has higher low-N tolerance compared to YLY900. In this study, field experiments were performed in 2020 and 2021 to compare the responses of yield attributes to N fertilization (180 kg N ha–1) relativized to zero-N fertilization between DY4727 and YLY900. Results showed that the response of grain yield to N fertilization was 13–55% for two varieties in two years. DY4727 had lower response of grain yield to N fertilization than YLY900 by 47% in 2020 and by 70% in 2021. There were no significant or consistent differences in responses of spikelets per m2, spikelet filling percentage, aboveground biomass, intercepted radiation, radiation use efficiency, and aboveground N uptake to N fertilization between DY4727 and YLY900. DY4727 had 32% and 26% lower positive response of grain weight to N fertilization compared to YLY900 in 2020 and 2021, respectively. The response of harvest index to N fertilization was negative (−3% in 2020 and −9% in 2021) for DY4727 but positive (1% in 2020 and 12% in 2021) for YLY900. DY4727 had higher negative response of internal N-use efficiency to N fertilization (−41% in 2020 and −24% in 2021) than YLY900 (−11% in 2020 and −10% in 2021). This study suggests that grain weight, harvest index, and internal N-use efficiency are key traits determining the difference in response of grain yield to N fertilization between DY4727 and YLY900.
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Olson, Monica B., Melba M. Crawford, and Tony J. Vyn. "Hyperspectral Indices for Predicting Nitrogen Use Efficiency in Maize Hybrids." Remote Sensing 14, no. 7 (April 2, 2022): 1721. http://dx.doi.org/10.3390/rs14071721.
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Enhancing the nitrogen (N) efficiency of maize hybrids is a common goal of researchers, but involves repeated field and laboratory measurements that are laborious and costly. Hyperspectral remote sensing has recently been investigated for measuring and predicting biomass, N content, and grain yield in maize. We hypothesized that vegetation indices (HSI) obtained mid-season through hyperspectral remote sensing could predict whole-plant biomass per unit of N taken up by plants (i.e., N conversion efficiency: NCE) and grain yield per unit of plant N (i.e., N internal efficiency: NIE). Our objectives were to identify the best mid-season HSI for predicting end-of-season NCE and NIE, rank hybrids by the selected HSI, and evaluate the effect of decreased spatial resolution on the HSI values and hybrid rankings. Analysis of 20 hyperspectral indices from imaging at V16/18 and R1/R2 by manned aircraft and UAVs over three site-years using mixed models showed that two indices, HBSI1 and HBS2, were predictive of NCE, and two indices, HBCI8 and HBCI9, were predictive of NIE for actual data collected from five to nine hybrids at maturity. Statistical differentiation of hybrids in their NCE or NIE performance was possible based on the models with the greatest accuracy obtained for NIE. Lastly, decreasing the spatial resolution changed the HSI values, but an effect on hybrid differentiation was not evident.
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Whan, Alex, Nicole Robinson, Prakash Lakshmanan, Susanne Schmidt, and Karen Aitken. "A quantitative genetics approach to nitrogen use efficiency in sugarcane." Functional Plant Biology 37, no. 5 (2010): 448. http://dx.doi.org/10.1071/fp09260.
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The economic and environmental consequences of inefficient use of nitrogen (N) fertiliser in agricultural crops is of concern worldwide, so new crop varieties with improved nitrogen use efficiency (NUE) are sought. Here, we report the first study of mapping quantitative trait loci (QTL) for nitrogen physiology traits in sugarcane. QTL analysis was undertaken for each parent of a segregating bi-parental sugarcane mapping population. We grew 168 progeny under limiting (0.2 mM NH4NO3) and non-limiting (5.0 mM NH4NO3) N supplies in two glasshouse experiments. Significant marker-trait associations (MTA) were detected in each treatment for shoot dry weight, root dry weight, total shoot N, shoot internal NUE (iNUE; measured as units shoot dry weight per unit N), leaf protein content and glutamine synthetase (GS) activity. MTA for GS activity did not co-locate with other traits except leaf protein content, indicating that variation in GS activity is not linked to plant size or iNUE during early growth. Under high N, there were no significant MTA for iNUE among markers from the male parent, Q165, an Australian commercial cultivar, but six MTA were found for markers inherited from the female parent, IJ76–514, a Saccharum officinarum ancestral variety. The results indicate that variation for iNUE under high N may be lower in commercial varieties than unimproved genotypes. Further, four MTA were consistent with previous field-based research on sugar and biomass production. Our study provides initial evidence that QTL may be incorporated in sugarcane breeding programs targeting improved NUE.
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Wierzbowska, Jadwiga, Stanisław Sienkiewicz, and Arkadiusz Światły. "Yield and Nitrogen Status of Maize (Zea mays L.) Fertilized with Solution of Urea—Ammonium Nitrate Enriched with P, Mg or S." Agronomy 12, no. 9 (September 2, 2022): 2099. http://dx.doi.org/10.3390/agronomy12092099.
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UAN is a popular nitrogen fertilizer, broadly used in world agriculture. Research concerning the effects of this fertilizer is just as common. Contrarily, studies on the combined application of UAN with P, Mg or S are lacking. This fact has stimulated our study, undertaken in order to evaluate the effects of maize grown for grain and fertilized with UAN enriched with the macronutrients (P, Mg and S) on the crop’s yields and nitrogen metabolism. The following nitrogen fertilizers were applied: UAN 32%N, UAN + S—26% N + 3% S, UAN + P (Medium)—26% N and 11% P2O5, UAN + P (Starter)—21% N and 18% P2O5, UAN + Mg—20% N + 4% Mg. Based on the results of chemical analyses and yields of maize, the following indicators of nitrogen use efficiency (NUE) were calculated: agricultural efficiency (AE), physiological efficiency (PE), internal N utilization efficiency (IE), reciprocal internal N utilization efficiency (RIE), grain share in N accumulation (HIN), recovery of N from mineral fertilizers (RN) and partial nitrogen balance (PNB). The highest grain yields were harvested after the application of UAN + S/UAN + Mg, and after the pre-sowing and top-dressing application of UAN or UAN + P (Medium). Values of all calculated nitrogen use efficiency indicators were more strongly dependent on the weather conditions, which determined volumes of maize yields in a given year, than on the applied fertilization.
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Dantas, Damiana Ferreira da Silva, Ronaldo Nascimento, Ademar Pereira Oliveira, Lourival Ferreira Cavalcante, Naysa Flávia Ferreira Nascimento, and Tony Andreson Guedes Dantas. "Gas exchange and photosynthetic pigments in zucchini plants under cattle bio-fertilization and sources of nitrogen." Research, Society and Development 9, no. 11 (December 4, 2020): e8099118107. http://dx.doi.org/10.33448/rsd-v9i11.8107.
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Zucchini is traditionally used in human consumption, however, the scarcity of information, especially about fertilization and the physiological aspects of this crop, constitutes a major obstacle its cultivation and commercialization. The objective was evaluate the chlorophyll content and gas exchange under cattle bio-fertilization and different sources of nitrogen. The work was carried a randomized block experimental design was used in a factorial scheme 5 x 3 + 1 composed of five cattle bio-fertilizer concentrations, three sources of nitrogen and an additional treatment without nitrogen. The levels of chlorophyll a, b and total, liquid photosynthesis, transpiration, internal CO2 concentration, stomatal conductance, instantaneous water use efficiency, and instantaneous carboxylation efficiency were evaluated. The studied variables were influenced by the interaction between the concentrations of the cattle bio-fertilizer and the nitrogen sources, except for the chlorophyll b content and the instantaneous water use efficiency, which responded only to the nitrogen sources. Ammonium sulfate and urea increased increase the physiological variables evaluated. The combination of ammonium sulfate with bio-fertilizer promoted an increase in chlorophyll a, total chlorophyll, liquid photosynthesis, transpiration, internal carbon concentration, stomatal conductance, and instantaneous carboxylation efficiency. The cattle bio-fertilizer in the soil without nitrogen did not increase the physiological variables evaluated.
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dos Santos, Adriano, Antônio Teixeira do Amaral Júnior, Samuel Henrique Kamphorst, Gabriel Moreno Bernardo Gonçalves, Pedro Henrique Araújo Diniz Santos, Janieli Maganha Silva Vivas, Gabrielle Sousa Mafra, et al. "Evaluation of Popcorn Hybrids for Nitrogen Use Efficiency and Responsiveness." Agronomy 10, no. 4 (April 1, 2020): 485. http://dx.doi.org/10.3390/agronomy10040485.
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The global boom in agricultural production has been associated with the exponential increase of nitrogen (N) fertilizer application. This heavy use of nitrogen in agriculture has caused negative impacts on the environment. Therefore, new alternatives are needed to maintain or increase maize yield but reduce the environmental impact. For this purpose, one possibility is to plant N-use efficient (NUE) cultivars. In this context, the objective of this study was to identify popcorn hybrid cultivars that are highly NUE and N-responsive, bred from crosses between inbred lines with contrasting levels of N-use efficiency. For this purpose, 90 hybrids were evaluated in a 10 × 10 triple lattice design at two sites and two levels of N availability (low and ideal availability). The results indicated that for the environment with low nitrogen availability, the lack of nitrogen reduced the chlorophyll content, extended the interval between male and female flowering, and affected the performance of the tested hybrids. However, we observed the existence of hybrids with greater efficiency than the responsiveness to nitrogen and with high productivity. These can even be used on farms where the level of production inputs is low, thus contributing to ensure food security.
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Mamun, MAA, MM Haque, QA Khaliq, MA Karim, AJMS Karim, AJ Mridha, and MA Saleque. "Yield and Nitrogen Use Efficiency of Locally Improved Rice Varieties in Rice Based Tidal Flooded Ecosystem of Bangladesh." Bangladesh Agronomy Journal 19, no. 2 (March 10, 2017): 39–49. http://dx.doi.org/10.3329/baj.v19i2.31851.
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An on farm field experiment was conducted to evaluate locally improved aman rice varieties in terms of nitrogen use efficiency and grain yield in southern region of Bangladesh. The treatments were: i. deep placement of urea (UDP) before panicle initiation stage and ii. farmers practice (FP/control). The locally popular rice varieties were used as planting materials. Higher panicles m-2 and grains panicle-1 was obtained from UDP application compared to FP. Nitrogen fertilization increases grain and straw nitrogen content significantly. Application of urea before panicle initiation stage gave considerable higher grain yield in all cultivated varieties. Cultivated aman varieties produced 2.0 to 2.5 t ha-1 grain without application of N fertilizer. But, cultivated local variety Razashail, Kutiagoni, Sadachikon, Sadapajam, Lalmota and Sadamota gave 3.0 to 3.5 t ha-1 grain in tidal prone areas with UDP. Hence, application of urea gave yield advantage by 0.5 to 1.0 t ha-1. The highest internal, agronomic, recovery and physiological efficiency; nitrogen harvest and grain yield efficiency index was obtained from Kutiagoni, Lalpayka, Sadachikon, Sadapajam, Moulata and Lalmota. Based on the yield and nitrogen fertilizer use efficiency, it could be concluded that UDP before panicle initiation stage is an effective option of urea application for rice cultivation in tidal prone areas.Bangladesh Agron. J. 2016 19(2): 39-49
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Li, Rongfa, Julin Gao, Yuanyuan Li, Shaobo Yu, and Zhigang Wang. "Heterosis for Nitrogen Use Efficiency of Maize Hybrids Enhanced over Decades in China." Agriculture 12, no. 6 (May 27, 2022): 764. http://dx.doi.org/10.3390/agriculture12060764.
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The nitrogen use efficiency (NUE) of modern maize hybrids has been greatly improved, but for decades, little was known on whether the NUE heterosis of maize hybrids had increased. A two-year field study was conducted on eight maize hybrids and their parental inbred lines from the 1970s to 2000s under two N levels (0, 150 kg N ha−1). These were the most popular hybrids in China’s main maize-growing areas at the time. The results showed that the yield of the maize hybrids increased significantly at an average rate of 37.5% every 10 years. The evolution of NUE heterosis was mainly related to the increased kernel number per ear. The absolute NUE heterosis (AHNUE) and the mid-parent NUE heterosis (MPHNUE) of maize hybrids increased by 151.4% and 76.4% in the past four decades, or an average rate of 2.11 kg kg−1 and 19.1% every 10 years. Based on the coefficient of determination, the contribution of the mid-parent nitrogen internal efficiency heterosis (MPHNIE) to MPHNUE (43–57%) was significantly higher than that of the mid-parent nitrogen recovery efficiency heterosis (MPHNRE) (19–32%), indicating that the evolution of maize NUE heterosis was mainly derived from its NIE heterosis evolution. The increase of NIE heterosis in the past 40 years was closely related to the increased heterosis of kernel number per ear, the pre-silking N accumulation and the post-silking N remobilization. Therefore, the enhancement of maize NUE heterosis can be attributed to (i) heterosis improvement in post-silking N remobilization, which results mainly from greater heterosis in pre-silking N accumulation; (ii) heterosis improvement in carbon and nitrogen sink capacity, which exhibit as heterosis enhancement in grain yield and grain nitrogen concentration. To further improve yield and NUE, the pre-silking N and carbon accumulation and post-silking N remobilization should both continue to increase in maize breeding. Our results will provide new insights into NUE and help breeders select genotypes with both higher yields and higher NUE for the future.
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Souza, Álvaro Henrique Cândido de, Roberto Rezende, Marcelo Zolin Lorenzoni, Fernando André Silva Santos, and André Maller. "Effect of fertigation with potassium and nitrogen on gas exchange and biomass accumulation in eggplant1." Pesquisa Agropecuária Tropical 47, no. 3 (September 2017): 345–52. http://dx.doi.org/10.1590/1983-40632016v4747885.
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ABSTRACT Adequate crop fertilization is one of the challenges for agriculture. Measuring gas exchange and biomass accumulation may be used to adjust crop management. The effect of fertigation with potassium (0 kg ha-1, 54 kg ha-1, 108 kg ha-1 and 216 kg ha-1) and nitrogen (0 kg ha-1, 67 kg ha-1, 134 kg ha-1 and 268 kg ha-1) on gas exchange and biomass accumulation in eggplant was assessed under greenhouse conditions. The net photosynthesis, stomatal conductance, transpiration, internal CO2 concentration, instantaneous carboxylation efficiency, water-use efficiency and total dry weight were evaluated. With the exception of K for water-use efficiency and N for internal CO2 concentration, all the other gas exchange parameters were significantly affected by the K and N doses. There was an interaction between N and K doses for net photosynthesis, stomatal conductance, transpiration and instantaneous carboxylation efficiency. The highest values for net photosynthesis, stomatal conductance, transpiration rate, carboxylation instantaneous efficiency and total dry weight were found in the range of 125-185 kg ha-1 of K and 215-268 kg ha-1 of N.
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Du, Ming, Wenzhong Zhang, Jiping Gao, Meiqiu Liu, Yan Zhou, Dawei He, Yanze Zhao, and Shiming Liu. "Improvement of Root Characteristics Due to Nitrogen, Phosphorus, and Potassium Interactions Increases Rice (Oryza sativa L.) Yield and Nitrogen Use Efficiency." Agronomy 12, no. 1 (December 23, 2021): 23. http://dx.doi.org/10.3390/agronomy12010023.
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Although nitrogen (N), phosphorus (P), and potassium (K) co-application improves crop growth, yield, and N use efficiency (NUE) of rice, few studies have investigated the mechanisms underlying these interactions. To investigate root morphological and physiological characteristics and determine yield and nitrogen use parameters, rhizo-box experiments were performed on rice using six treatments (no fertilizer, PK, N, NK, NP, and NPK) and plants were harvested at maturity. The aboveground biomass at the elongating stage and grain yield at maturity for NPK treatment were higher than the sum of PK and N treatments. N, P, and K interactions enhanced grain yield due to an increase in agronomic N use efficiency (NAE). The co-application of N, P, and K improved N uptake and N recovery efficiency, exceeding the decreases in physiological and internal NUE and thereby improving NAE. Increases in root length and biomass, N uptake per unit root length/root biomass, root oxidation activity, total roots absorption area, and roots active absorption area at the elongating stage improved N uptake via N, P, and K interactions. The higher total N uptake from N, P, and K interactions was due to improved root characteristics, which enhanced the rice yield and NUE.
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Shabanov, A. V., D. V. Kondratiev, V. K. Vanin, and A. Yu Dunin. "The issue of improving the efficiency of nitrogen oxide neutralization systems in diesel internal combustion engines." Izvestia MGTU MAMI 1, no. 2 (2021): 101–12. http://dx.doi.org/10.31992/2074-0530-2021-48-2-101-112.
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The most effective method of reducing nitrogen oxides in diesel exhaust gas is selective purifica-tion by the SCR-NH3 method. The method uses ammonia released during thermolysis and hydroly-sis of a urea solution when it is injected through a nozzle into a neutralizer. This method has a rela-tively low efficiency of cleaning the exhaust gas from nitrogen oxides. The main factor hindering the achievement of high efficiency of the NOx neutralization system is the insufficiently high tem-perature during the implementation of this process. The article analyzes various ways to increase the efficiency of the neutralization process and proposes a new method for neutralizing NOx by using urea injection into the cylinders of the inter-nal combustion engine at the expansion stroke in a diesel internal combustion engine. Efficiency can be achieved due to a higher exhaust gas temperature in the cylinder of the internal combustion engine and an increase in the time of the process of thermolysis and hydrolysis of urea. The kinetics of the decomposition of nitrogen oxides, the process of NH3 oxidation, and the cal-culation of temperature conditions in the cylinder of a diesel internal combustion engine at the ex-haust cycle are considered. The experience of neutralization of NOx contained in the flue gases of thermal power plants, where NOx purification takes place at high temperatures without the use of a catalyst, is analyzed. It is shown that the modernization of the SCR-NH3 process, due to the injection of urea at the exhaust stroke in a diesel internal combustion engine, will simplify the existing method of NOx neutralization and at the same time obtain additional advantages for a modern high-speed engine
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Wang, Zhongcheng, Sergejus Lebedevas, Paulius Rapalis, Justas Zaglinskis, Rima Mickeviciene, Vasilij Djackov, and Xiaoyu Liu. "Use of LNG Cold Potential in the Cogeneration Cycle of Ship Power Plants." Journal of Marine Science and Engineering 8, no. 9 (September 18, 2020): 720. http://dx.doi.org/10.3390/jmse8090720.
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This paper presents the results of a numerical study on the parameters that affect the efficiency of the cogeneration cycle of a ship’s power plant. The efficiency was assessed based on the excess power (Ngen.) of a free turbine, operated with the inflow of gaseous nitrogen, which was used to generate electricity. A mathematical model and simulation of the regenerative cycle were created and adjusted to operate with a dual-fuel (diesel-liquid natural gas (LNG)) six-cylinder four-stroke engine, where the energy of the exhaust gas was converted into mechanical work of the regenerative cycle turbine. The most significant factors for Ngen. were identified by parametrical analysis of the cogeneration cycle: in the presence of an ‘external’ unlimited cold potential of the LNG, Ngen. determines an exhaust gas temperature Teg of power plant; the pressure of the turbo unit and nitrogen flow are directly proportional to Ngen. When selecting the technological units for cycle realization, it is rational to use high flow and average πT pressure (~3.0–3.5 units) turbo unit with a high adiabatic efficiency turbine. The effect of the selected heat exchangers with an efficiency of 0.9–1.0 on Ngen. did not exceed 10%. With LNG for ‘internal’ use in a ship as a fuel, the lowest possible temperature of N2 is necessary, because each 10 K increment in N2 entering the compressor decreases Ngen. by 5–8 kW, i.e., 5–6%.
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Campos, Allan R. F., Rosiane L. S. de Lima, Carlos A. V. de Azevedo, Ronaldo do Nascimento, and Sonivagno S. Silva. "Physiological attributes of jatropha under different planting densities and nitrogen doses." Revista Brasileira de Engenharia Agrícola e Ambiental 20, no. 12 (December 2016): 1112–17. http://dx.doi.org/10.1590/1807-1929/agriambi.v20n12p1112-1117.
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ABSTRACT Nitrogen (N) fertilization associated with planting density is a practice that can improve the physiological aspects and consequently increase the yield of a crop. Thus, this study aimed to evaluate the effects of planting density and N levels on the physiological aspects of jatropha in the ‘Agreste’ region of Paraíba. Treatments consisted of four planting densities (833, 1,111, 1,666 and 2,500 plants ha-1) representing the plots and five N doses (0, 40, 80, 120 and 180 kg ha-1) corresponding the subplots. The effects of treatments on CO2 assimilation rate, internal CO2 concentration, transpiration, stomatal conductance, water use efficiency, instantaneous carboxylation efficiency and SPAD index were analysed. Except for stomatal conductance, the other variables were influenced by the interaction between planting densities and N levels. The association of the dose of 80 kg ha-1 with a planting density of 2,200 plants ha-1 provided adequate conditions for the production of plants with increased photosynthetic activity and efficient use of water.
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HUANG, MIN, SHUANGLÜ SHAN, XIAOBING XIE, XUEFENG ZHOU, YINGBIN ZOU, and NORMAN UPHOFF. "GRAIN YIELD AND NITROGEN UTILIZATION IN RESPONSE TO REDUCING NITROGEN RATE IN HYBRID RICE TRANSPLANTED AS SINGLE SEEDLINGS." Experimental Agriculture 55, no. 04 (July 11, 2018): 637–48. http://dx.doi.org/10.1017/s0014479718000261.
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SUMMARYTransplanting single seedlings rather than seedlings in clumps has been increasingly attractive in hybrid rice production in China due to reduced seed requirements and higher grain yield. This study was conducted to determine grain yield and nitrogen (N) utilization in response to reductions in the N rate in hybrid rice under single-seedling transplanting. Field experiments were done in 2015 and 2016 on a moderate to high fertility soil at the Experimental Farm of Hunan Agricultural University, China. The hybrid rice cultivar Liangyoupeijiu (LYPJ) was used in 2015, and two hybrid cultivars LYPJ and Xiangliangyou 900 were used the next year. In each year, the rice plants transplanted with a single seedling per hill were grown with three N rates, including the usual N rate (150 kg ha–1) and two reduced N rates (120 and 90 kg ha–1). Grain yield, yield attributes, and N uptake and use efficiency were determined for each N rate. Significant reduction in grain yield was observed in only one of three cultivar-year combinations when N rate was reduced by 20% (from 150 to 120 kg ha–1), and the magnitude of yield reduction was only 4%. Although significant reduction in grain yield was observed in two of the three cultivar-year combinations when N rate reduced by 40% (to 90 kg ha–1), the highest yield reduction was only 7%. Yield attributes were generally changed slightly when N rate was reduced by 20%, while compensation among yield attributes and N utilization characteristics could explain why a 40% reduction in N rate did not result in substantial yield loss. Partial factor productivity of applied N (PFPN) was increased by 21–24% and 56–63% with 20% and 40% reductions in the N rate, respectively. The higher PFPN with a reduced N rate was attributed to higher recovery efficiency of applied N (REN) or to both higher REN and internal N use efficiency. Our study suggests that reducing N rate does not necessarily result in yield loss due to compensation among yield components and increased N use efficiency in hybrid rice transplanted as single seedlings under moderate to high soil fertility conditions.
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Olson, Monica B., Melba M. Crawford, and Tony J. Vyn. "Predicting Nitrogen Efficiencies in Mature Maize with Parametric Models Employing In-Season Hyperspectral Imaging." Remote Sensing 14, no. 22 (November 20, 2022): 5884. http://dx.doi.org/10.3390/rs14225884.
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Overuse of nitrogen (N), an essential nutrient in food production systems, can lead to health issues and environmental degradation. Two parameters related to N efficiency, N Conversion Efficiency (NCE) and N Internal Efficiency (NIE), measure the amount of total biomass or grain produced, respectively, per unit of N in the plant. Utilizing remote sensing to improve these efficiency measures may positively impact the stewardship of agricultural N use in maize (Zea mays L.) production. We investigated in-season hyperspectral imaging for prediction of end-season whole-plant N concentration (pN), NCE, and NIE, using partial least squares regression (PLSR) models. Image data were collected at two mid-season growth stages (V16/V18 and R1/R2) from manned aircraft and unmanned aerial vehicles for three site years of 5 to 9 maize hybrids grown under 3 N treatments and 2 planting densities. PLSR models resulted in accurate predictions for pN at R6 (R2 = 0.73; R2 = 0.68) and NCE at R6 (R2 = 0.71; R2 = 0.73) from both imaging times. Additionally, the PLSR models based on the R1 images, the second imaging, accurately distinguished the highest and lowest ranked hybrids for pN and NCE across N rates. Neither timepoint resulted in accurate predictions for NIE. Genotype selection efficiency for end-season pN and NCE was increased through the use of the in-season PLSR imaging models, potentially benefiting early breeding screening methods.
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Shelp, Barry J., William J. Sutton, and Edward J. Flaherty. "Strategic timing and rate of phosphorus fertilization improves phosphorus-use efficiency in two contrasting cultivars of subirrigated greenhouse-grown chrysanthemum." Canadian Journal of Plant Science 100, no. 3 (June 1, 2020): 264–75. http://dx.doi.org/10.1139/cjps-2019-0173.
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Greenhouse floriculture operations pose significant environmental risk due to extensive inputs of fertilizer, especially nitrogen and phosphorus (P). Recent evidence shows that the use efficiency for nitrogen or sulphur is markedly improved in subirrigated potted chrysanthemums (Chrysanthemum morifolium Ramat.) by supplying a moderate level of the nutrient during vegetative growth, and removing the entire nutrient suite at the onset of reproductive growth, without adverse effects on plant quality. Here, two split-plot experiments were conducted with subirrigated, potted, disbudded chrysanthemums grown in a peat:perlite mixture under greenhouse conditions (high- or low-ambient light) with inorganic orthophosphate (Pi) treatment (2.6 mmol L−1 Pi supplied during the vegetative and reproductive stages, and 2.6, 1.95, or 1.3 mmol L−1 Pi supplied during the vegetative stage only) as the main plot and cultivar (‘Olympia’ and ‘Covington’) as the subplot. Market quality plants with sufficient tissue P were produced even when Pi delivery was reduced by approximately 75% over the crop cycle, compared with industry standards. The primary mechanism for sustaining plant growth with decreasing Pi delivery was improved acquisition or uptake efficiency, although some changes in internal P-utilization efficiency were evident, including the remobilization of both organic P and Pi during inflorescence development. Differences in biomass yields, tissue P concentrations, content-based P-use efficiency (PUEC = mg shoot dry mass/mg shoot P content) with constant Pi acquisition, and uptake- versus remobilization-based P supply for inflorescence growth established that ‘Olympia’ has a greater P-utilization efficiency than ‘Covington’. This modified subirrigation practice could contribute significantly to low-input production of floricultural crops.
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Ribeiro, João Everthon da Silva, Arliston Pereira Leite, José Eldo Costa, Manoel Bandeira de Albuquerque, and Fábio Mielezrski. "Development, Physiology and Productivity of the Common Bean Under Different Nitrogen Doses." Journal of Agricultural Science 10, no. 6 (May 6, 2018): 171. http://dx.doi.org/10.5539/jas.v10n6p171.
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Among nutrients, nitrogen is required in the greatest quantities by bean culture. The objective of this work was to evaluate growth, physiological responses and productivity of the common bean cultivar, ‘IAC Imperador’ under varying nitrogen doses in Brejo Paraibano. The experiment was carried out at Fazenda Experimental Chã-de-Jardim (Chã-de-Jardim Experimental Farm), of the Centro de Ciências Agrárias of the Universidade Federal da Paraíba, in the municipality of Areia, state of Paraíba. The treatments comprised 0, 50, 100, 150 and 200 kg of nitrogen ha-1, applied in coverage at 35 days after sowing. To assess growth, plant height, stem diameter and number of leaves were evaluated. For gas exchange, photosynthesis rate, internal CO2 concentration, transpiration, stomatal conductance, instantaneous water use efficiency and instantaneous carboxylation efficiency were evaluated. For chlorophyll “a” fluorescence, minimum leaf fluorescence, maximum leaf fluorescence, variable maximum fluorescence, potential quantum efficiency of PSII (Photosystem II) and ratio (Fv/F0) were evaluated. For the components of primary productivity, the height of insertion of the first pod, number of pods per plant and the number of grains per pod were evaluated. Nitrogen fertilization in coverage significantly affected most of the growth, gas exchange and productivity variables, with the dose of 200 kg ha-1 being responsible for the highest values (p < 0.05). Chlorophyll fluorescence showed no significant differences among the nitrogen doses. The nitrogen doses influenced the growth, gas exchange and productivity of the common bean in the region of Brejo Paraibano.
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Mohamad Ahmed, Badr ELdin Abdelgadir, Faisal Elgasim Ahmed, and Hanadi Ibrahim Dessougi. "Effect of Water Stress, Nitrogen and Organic Manure Fertilizer on Nitrogen Use Efficiency Indices and Grain Protein Content of Wheat in a Semi-arid Environment." Academic Journal of Life Sciences, no. 65 (May 25, 2020): 34–38. http://dx.doi.org/10.32861/ajls.65.34.38.
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A field experiment was conducted for two consecutive seasons during 2010/2011 and 2011/2012 on the Demonstration Farm of the Faulty of Agriculture, University of Kassala at New Half. Nitrogen use efficiencies (i.e. agronomic AE, internal IE, physiological PE and recovery RE) and grain protein content were investigated at different level of watering regimes and organic manure application of wheat (Triticum aestivum L). The watering regime treatments were irrigation every 7, 14 and 21 days, and the nitrogen fertilizer levels were zero, 43, 86 kg N ha-1 without or with 4 tons of chicken manure ha-1. Frequent irrigation, addition of high N level and organic manure significantly increased AE, IE, PE, RE and grain protein content compared to their respective treatments. Mixing of organic manure and nitrogen fertilizer increased AE, IE and RE but resulted in a slightly increase in PE than both treatments when they were added solely. Further, the magnitude of organic manure on AE, IE, RE and grain protein content was significantly greater under normal watering regime. Wheat plants under optimum conditions (frequent watering, high N level plus organic manure) used N, as indicated by AE, PE, IE and RE, more efficiently than under other treatment combination.
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Aldous, Allison R. "Nitrogen retention by Sphagnum mosses: responses to atmospheric nitrogen deposition and drought." Canadian Journal of Botany 80, no. 7 (July 1, 2002): 721–31. http://dx.doi.org/10.1139/b02-054.
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Sphagnum mosses are assumed to be effective at acquiring low amounts of nitrogen (N) in precipitation to support annual growth. However, N concentrations in precipitation have increased from anthropogenic sources over the last 150 years. I hypothesized that N retention from wet atmospheric deposition decreases with increased N availability, by comparing Sphagnum mosses in a high N deposition region in the Adirondack Park, New York, to a low-deposition region in eastern Maine. A 15NH415NO3 tracer was applied to mosses in both regions, and retention after 24 h was estimated. Nitrogen retention ranged from 50 to 90% of N applied. Most 15N was recovered from the apical capitula and upper stems. Nitrogen retention was greater in the Maine sites in 1998. However, in 1999, a drought year, particularly in Maine, N retention was less in Maine than in New York. The drier climate appeared to lower N retention, possibly through its physiological effects on the mosses. Although atmospheric deposition might be the only exogenous source of N, it satisfied only a small fraction of N required for annual growth. These data suggest that internal cycling processes, such as mineralization, may be much more important N sources to support Sphagnum growth.Key words: Sphagnum mosses, atmospheric nitrogen deposition, nitrogen-use efficiency, nitrogen retention, peatlands, bogs, drought.
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Hsieh, Chia-Hsin, Ming-Hsien Hsueh, Cheng-Wen Chang, and Tao-Hsing Chen. "Effects of Reactive Species Produced by Electrolysis of Water Mist and Air through Non-Thermal Plasma on the Performance and Exhaust Gas of Gasoline Engines." Molecules 27, no. 20 (October 20, 2022): 7072. http://dx.doi.org/10.3390/molecules27207072.
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Countries are paying increasing attention to environmental issues and are moving towards the goal of energy saving and carbon reduction. This research presents a method to analyse the effects of the use of non-thermal plasma (NTP) and water injection (WI) devices on the efficiency of internal combustion engines. The devices were installed on the intake manifold to investigate the effects of additional substances produced by electrolysis on the engine performance and exhaust emissions. According to the results, the addition of the NTP and WI devices affected the power efficiency and the rate of change of the brake-specific fuel consumption (BSFC) of the internal combustion engines. In addition, the change rate of hydrocarbons (HC), carbon monoxide (CO), and nitrogen oxides (NOx) in the exhaust gases was affected. In conclusion, the study found that the additional substances generated by the NTP-electrolysed water mist or air influenced the fuel combustion efficiency and exhaust emissions.
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Reilly, K., and G. T. Attwood. "Detection of Clostridium proteoclasticumand Closely Related Strains in the Rumen by Competitive PCR." Applied and Environmental Microbiology 64, no. 3 (March 1, 1998): 907–13. http://dx.doi.org/10.1128/aem.64.3.907-913.1998.
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ABSTRACT A competitive PCR technique was used to enumerate the proteolytic bacterium Clostridium proteoclasticum from the rumen. A PCR primer, which circumscribes this organism and several closely related strains, was designed for a variable region within their 16S rRNA genes and was used in conjunction with a universal forward primer. This primer pair was tested for specificity against 85 ruminal bacterial strains. An internal control DNA was constructed for use in competitive PCRs and was shown to amplify under the same reaction conditions and with the same amplification efficiency as the target DNA. DNA from a known number of C. proteoclasticum cells was coamplified with the internal control to construct a standard curve. Rumen samples were collected from eight dairy cows fed four diets in rotation: high nitrogen, high nitrogen supplemented with carbohydrate, low nitrogen, and low nitrogen supplemented with carbohydrate. DNA extracted from these and spiked with internal control DNA was amplified with the C. proteoclasticum primer pair. The relative intensities of the PCR products were used to quantitate the numbers ofC. proteoclasticum cell equivalents from the rumen samples. The numbers ranged from 2.01 × 106ml−1 to 3.12 × 107 ml−1. There was no significant effect on the numbers of C. proteoclasticum detected in rumen samples among cows fed the four diets. The utility of the competitive PCR approach for quantifying ruminal bacterial populations in vivo and the occurrence ofC. proteoclasticum in forage-fed dairy cows are discussed.
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Cinti, G., A. Baldinelli, G. Bidini, and L. Barelli. "Electrochemical Impedance Spectroscopy study on ammonia-fed Solid Oxide Fuel Cells." Journal of Physics: Conference Series 2385, no. 1 (December 1, 2022): 012052. http://dx.doi.org/10.1088/1742-6596/2385/1/012052.
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Abstract The use of ammonia as a fuel is one of the promising pathways to decarbonize the energy sector. When ammonia is converted into power in the so-called “Ammonia-to-Power”, the most interesting technology is the Solid Oxide Fuel Cell (SOFC) that can operate directly with ammonia and reach high performance in terms of efficiency. SOFCs are a high-efficiency and, potentially, low-cost technology, but still suffer from degradation issues related to internal losses. An innovative experimental technique to evaluate losses evolution caused by degradation is electrical impedance spectroscopy (EIS), followed by measurement data post-processing through the Distribution of Relaxation Times (DRT) analysis. In this study, a single SOFC is studied with a combined EIS and DRT methodology, when operating with a gas mixture of hydrogen, nitrogen and ammonia. The results identify the contribution to DRT of fuel dilution and the internal ammonia decomposition reaction.
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Rawal, Nabin, Keshab Raj Pande, Renuka Shrestha, and Shree Prasad Vista. "Nutrient use efficiency (NUE) of wheat (Triticum aestivum L.) as affected by NPK fertilization." PLOS ONE 17, no. 1 (January 27, 2022): e0262771. http://dx.doi.org/10.1371/journal.pone.0262771.
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Nutrient use efficiency is crucial for increasing crop yield and quality while reducing fertilizer inputs and minimizing environmental damage. The experiments were carried out in silty clay loam soil of Lalitpur, Nepal, to examine how different amounts of nitrogen (N), phosphorus (P), and potassium (K) influenced crop performance and nutrient efficiency indices in wheat during 2019/20 and 2020/21. The field experiment comprised three factorial randomized complete block designs that were replicated three times. N levels (100, 125, 150 N kg ha-1), P levels (25, 50, 75 P2O5 kg ha-1), and K levels (25, 50, 75 K2O kg ha-1) were three factors evaluated, with a total of 27 treatment combinations. Grain yields were significantly increased by N and K levels and were optimum @ 125 kg N ha-1 and @ 50 kg K2O ha-1 with grain yields of 6.33 t ha-1 and 6.30 t ha-1, respectively. Nutrient levels influenced statistically partial factor productivity, internal efficiency, partial nutrient budget, recovery efficiency, agronomic efficiency, and physiological efficiency of NPK for wheat. Nutrient efficiency was found to be higher at lower doses of their respective nutrients. Higher P and K fertilizer rates enhanced wheat N efficiencies, and the case was relevant for P and K efficiencies as well. Wheat was more responsive to N and K fertilizer, and a lower rate of P application reduced N and K fertilizer efficiency. This study recommends to use N @ 125 kg ha-1, P2O5 @ 25 kg ha-1 and K2O @ 50 kg ha-1 as an optimum rate for efficient nutrient management in wheat in mid-hills of Nepal.
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Sievers, M., K. D. Vorlop, J. Hahne, M. Schlieker, and S. Schäfer. "Pre-nitrification by encapsulated nitrifiers - a possibility for self-sufficient energy operation of domestic WWTPs." Water Science and Technology 47, no. 11 (June 1, 2003): 173–80. http://dx.doi.org/10.2166/wst.2003.0602.
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The overall energy consumption of domestic wastewater treatment plants (WWTPs) increases with treatment efficiency. Approximately 30 to 45 kWh per people equivalent and year is mostly necessary for advanced nitrogen and phosphorus removal, while the aeration contains the main part of approximately 60%. A new process using encapsulated nitrifiers on gel lens beads is introduced to overcome the high energy consumption of aeration. A more selective nitrification process was found at a nitrification rate of between 50 and 60 mg nitrogen per hour and litre reaction volume corresponding to a hydraulic retention time (HRT) of about 30 to 60 minutes while the soluble Chemical Oxygen Demand (COD) removal could be less than 30% depending on operational conditions of the bio-reactor. The latter enables internal use of wastewater's COD for a post denitrification. For the new process the energy consumption as well as total volume of bio-reactor are much less (approximately 30 to 50% for both) than conventional processes due to the low sludge age for COD and nitrate removal and the avoidance of internal wastewater recycle. Therefore, self-sufficient energy operation of domestic WWTPs operating with advanced treatment efficiency could become possible, if energy recovery by anaerobic sludge digestion is included.
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Nunes de Lima, Firmino, Osvaldo Kiyoshi Yamanishi, Márcio de Carvalho Pires, Elias Divino Saba, Aline Rodrigues Pereira, and Gabriel Soares Miranda. "Ecophysiology of the Southern Highbush blueberry cv. Biloxi in response to nitrogen fertigation." Comunicata Scientiae 11 (March 12, 2020): e3245. http://dx.doi.org/10.14295/cs.v11i0.3245.
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In Brazil, the nutritional requirements of the blueberry are not sufficiently known, thus requiring further research on the management of mineral fertilization. In this perspective, this work aimed to evaluate physiological attributes of Southern Highbush blueberry plants cv. Biloxi as a function of nitrogen fertigation in Brasília-DF. The experiment was conducted from August 2018 to July 2019, in the Fruit Sector of the Experimental Biology Station of the University of Brasilia (UnB), Federal District. This experiment adopted a randomized block design, with four treatments: 10; 20; 30, and 40 g of N plant-1, 8 replications, and 5 plants per experimental plot. The following variables were measured: net photosynthesis rate (A), transpiration (E), stomatal conductance (gs), internal CO2 concentration (Ci), instantaneous water-use efficiency (WUE), carboxylation efficiency (CE), SPAD index (SPAD) and leaf nitrogen (N). There was an effect of the different nitrogen doses applied on the physiological attributes. The plants of the blueberry cultivar Biloxi increased their photosynthetic rates at doses up to 30 g of N plant-1. Nitrogen rates did not influence stomatal conductance nor did they provide improvements in the carboxylation efficiency of the blueberry plants. Under the conditions of the present work, the highest N leaf contents were obtained with the application of 30 g N plant-1, and values above this concentration did not correspond to higher net photosynthesis rates, transpiration, and CO2 concentration in the leaf mesophyll.
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Chen, Kaiwen, Tao Ma, Jihui Ding, Shuang’en Yu, Yan Dai, Pingru He, and Teng Ma. "Effects of Straw Return with Nitrogen Fertilizer Reduction on Rice (Oryza sativa L.) Morphology, Photosynthetic Capacity, Yield and Water–Nitrogen Use Efficiency Traits under Different Water Regimes." Agronomy 13, no. 1 (December 30, 2022): 133. http://dx.doi.org/10.3390/agronomy13010133.
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The sustainability of rice (Oryza sativa L.) cultivation has been threatened by water deficit and nitrogen (N)-fertilizer abuse. Straw return combined with N-fertilizer reduction could be an effective agronomic practice to improve N-use efficiency in rice production, but the interaction with water-saving irrigation regimes remains largely unknown. Here, a 2-year paddy field experiment was conducted to elucidate the effects of irrigation regime (continuously flooded, CF; controlled irrigation and drainage, CID) and straw return with N reduction (conventional farmers’ fertilization practice of 300 kg N ha−1 without straw return, N300; straw return with 25% N reduction, SN225; straw return with 50% N reduction, SN150) on rice growth dynamics, grain yield and water–nitrogen utilization. The results showed that CID significantly affected photosynthesis and fluorescence indicators, and increased grain yield and water productivity of rice. Straw return with N reduction reduced most rice growth traits, exhibiting lower plant height, tillers, leaf photosynthesis, chlorophyll fluorescence and dry matter accumulation, especially in vegetative growth under CF. In contrast, SN225 under CID showed compensatory effects on photosynthetic and fluorescence traits, thus improving N uptake during the reproductive growth stage. Despite a 6.6–7.1% yield reduction in SN225, 25% of N-fertilizer input was saved, with a corresponding increase in internal N-use efficiency and N-partial factor productivity. Overall, the present study indicates that straw return combined with moderate N deficiency might be a more eco-friendly and sustainable agronomic practice in water-saving irrigated rice fields.
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Husain, Tariq. "Pakistan’s Energy Sector Issues: Energy Efficiency and Energy Environmental Links." LAHORE JOURNAL OF ECONOMICS 15, Special Edition (September 1, 2010): 33–59. http://dx.doi.org/10.35536/lje.2010.v15.isp.a3.
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This paper analyzes Pakistan’s energy sector issues and highlights (i) the importance of the link between energy and the environment, and (ii) the central importance of energy efficiency for high return demand-side solutions to meet the country’s energy needs. The paper argues that energy planning should integrate the external cost of energy use in deciding about the composition of supply: coal, oil, gas, hydropower, renewable, nuclear, and solar. By utilizing external cost estimates made by the European Commission for Europe, and the US National Academy of Sciences, a total cost (external + internal) ranking of primary energy sources for Pakistan is estimated. This estimate is at the low end of the cost spectrum because classic pollutants—sulfur dioxide, nitrogen oxides, carbon monoxide—in Pakistan are significantly higher than in Europe or the US. The paper also discusses the experiences of China and OECD countries in increasing energy-wide efficiency. A central lesson emerging from the analysis is that Pakistan will have to significantly increase its energy-related research and development expenditure in order to adequately address its energy sector issues. A quadrupling from 0.25 % of gross domestic product is recommended over a decade.
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Levishko, A., I. Gumeniuk, Ye Tkach, Yu Ternovyi, and Yu Kravchuk. "Efficiency of using new Rhizobium strains on legume crops." Agroecological journal, no. 1 (February 14, 2022): 136–44. http://dx.doi.org/10.33730/2077-4893.1.2022.257130.
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During significant time, the use of bean-rhizobial systems and development of effective, competitive microbial preparations have been an integral part of organic farming. Also, in intensive technologies, only due to such ones, it is possible without reducing the achieved level of agricultural production to reduce its cost, harmful effects on the environment and at the same time to achieve ecological purity of products selection of highly effective strains that have adapted to local soil and climatic conditions and acquired resistance to nutrients and plant protection is the most promising strategy to increase the effectiveness of microbial inoculants. The aim of this work was to select highly effective strains that have adapted to local soil and climatic conditions and have become resistant to nutrients and plant protection and are the most promising for improving the effectiveness of microbial inoculants. Field researches were conducted in the research fields of the Skvyra Research Station of Organic Production of the Institute of Agroecology and Environmental Management of NAAS (Ukraine, Kyiv region, Skvyra) during 2020–2021. Nitrogen-fixing activity of root nodules was determined by acetylene method. The gas mixture was analyzed on an «Agilent 6850 chromatograph». The paper presents the results of research to establish the effectiveness of new strains of inoculants on crops of legumes: soybean of Moravia variety and peas of Starter variety in the Kyiv region, Skvyra Research Station of Organic Production of the Institute of Agroecology and Environmental Management of NAAS. The significant effect of new rhizobia strains for inoculation of legumes on phenological indicators and yield of these crops in the conditions of intensive technologies was shown. The competitiveness of strains is controlled by both internal determinants — genotype of the microorganism, and external factors such as symbiont plant physiology, exposure to abiotic factors, tolerance to pesticides and agrochemicals used in crop production technologies. It has been shown that the use for inoculation of soybean strain B. japonicum EL 35 and for inoculation of peas strain R. leguminosarum bv. viciae PS 12 stimulate the development of plants during their growing season and allow to obtain symbiotic systems with a high level of nitrogen fixation, as a result of which we can increase the yield of legumes from 16 to 20%.
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Беляев, В. И., В. Э. Буксман, and Р. Е. Прокопчук. "THE EFFECTIVENESS OF THE USE OF VARIOUS FORMS OF NITROGEN IN THE CULTIVATION OF SPRING RAPE AND SOYBEANS IN THE ALTAI TERRITORY." Vestnik APK Verhnevolzh`ia, no. 2(58) (June 30, 2022): 12–18. http://dx.doi.org/10.35694/yarcx.2022.58.2.002.
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Последние годы в Алтайском крае наблюдается расширение посевных площадей ярового рапса и сои. Применение различных вариантов технологий их возделывания требует обоснования режима питания растений, в том числе азотного. Особенно это актуально в хозяйствах, где применяется технология «No-Till» с оставлением на поверхности растительных остатков, а также с появлением ликвилайзеров, позволяющих выполнять точечную инъекцию жидких минеральных удобрений в почву, в т.ч. КАС-32 с различными формами азота. Внутрипочвенное внесение жидких и гранулированных минеральных удобрений – одно из перспективных направлений повышения эффективности возделывания сельскохозяйственных культур. Вид удобрений, способ внесения и дозировка существенно влияют на урожайность культур и качество зерна. Большим преимуществом жидких минеральных удобрений (КАС-32) является то, что они содержат различные формы азота и обеспечивают пролонгированное действие по вегетации, что особенно важно в засушливые годы. Агрегаты для внесения удобрений в почву позволяют доставлять необходимое количество питательных веществ в почву в легкодоступной форме. В результате существенно повышается эффективность использования почвенной влаги и растёт урожайность возделываемых культур. Внутрипочвенное внесение жидких минеральных удобрений в опытах проводилось c помощью ликвилайзера «Duport», снабжённого инъекторами в форме игл, которые впрыскивают точечно жидкие удобрения на нужную глубину в почву. В статье анализируется эффективность применения гранулированных и жидких минеральных удобрений (КАС-32) при возделывании ярового рапса и сои в ООО «Вирт» Целинного района Алтайского края, где уже 16 лет применяется технология «No-Till». Оценивалась урожайность культур и эффективность производства зерна при различных дозах внесения гранулированного азота (азотно-магниевое удобрение) и в жидком виде (КАС-32). In recent years, in the Altai Territory, there has been an expansion of the sown areas of spring rape and soybeans. The use of various options for their cultivation technologies requires substantiation of the plant nutrition regime, including nitrogen one. This is especially true in farms where the "No-Till" technology is used with the leaving of plant residues on the surface, as well as with the advent of liquilizers that allow the point injection of liquid mineral fertilizers into the soil, including KAS-32 with various forms of nitrogen. Internal soil application of liquid and granulated mineral fertilizers is one of the promising areas for increasing the efficiency of crop cultivation. The type of fertilizer, the method of application and dosage significantly affect the yield of crops and the quality of grain. A great advantage of liquid mineral fertilizers (KAS-32) is that they contain various forms of nitrogen and provide a prolonged vegetation effect, which is especially important in dry years. Soil fertilizer implements allow you to deliver the required amount of nutrients to the soil in an easily accessible form. As a result, the efficiency of using soil moisture is significantly increased and the yield of cultivated crops increases. The internal soil application of liquid mineral fertilizers in the experiments was carried out using the "Duport" liquidizer equipped with needle-shaped injectors that inject point-liquid fertilizers to the desired depth into the soil. The article analyzes the effectiveness of the use of granular and liquid mineral fertilizers (KAS-32) in the cultivation of spring rape and soybeans in OOO "Virt" in the Tselinniy District of Altai Territory, where the No-Till technology has been used for 16 years. The yield of crops and the efficiency of grain production at various doses of granulated nitrogen (nitrogen-magnesium fertilizer) and in liquid form (KAS-32) were evaluated.
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Leach, K. A., D. J. Roberts, and D. L. Swain. "Assessment and Improvement of the Efficiency of Nitrogen Use in Clover Based and Fertilizer Based Dairy Systems. 2. Beyond Benchmarking to Internal System Components." Biological Agriculture & Horticulture 20, no. 2 (January 2002): 157–74. http://dx.doi.org/10.1080/01448765.2002.9754959.
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Shchokin, V., and О. Shchokina. "APPLICATION OF HUMATIC REAGENT FOR DUST DESTRUCTION AND DEGASATION IN MASS EXPLOSIONS." POWER ENGINEERING: economics, technique, ecology, no. 1 (October 11, 2021): 132–36. http://dx.doi.org/10.20535/1813-5420.1.2021.242194.
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The work is devoted to the coverage of the results of research and industrial tests of environmental efficiency of water replacement in internal and external hydraulic wells in the quarries of mining enterprises for humic reagent [1]. Scientific and technical problem of determining environmental efficiency, solved by conducting in 2020 by the Research Mining Institute (NDGRI KNU) industrial research in the conditions of PJSC "Northern Mining and Processing Plant" (PJSC "PIVNGZK", Kryvyi Rih) kg / dust3 kg rocks) and gas formation (kg / kg BP) during mass explosions with the use of water in the holes in comparison with the use of humic reagent. Dust- binding and degassing properties of humate-based reagents are confirmed by the results of research and industrial tests conducted by the Research Institute of Occupational Safety and Ecology in the Mining and Metallurgical Industry (NDIBPG KNU) in 2019 by conducting experiments with pre-wetting blocks before conditions of quarries of Inguletskyi, Central and Northern GZK [1]. According to the results of experimental and industrial tests, it is substantiated that the efficiency of the use of humic reagent in the external water hammer in comparison with the use of technical water was: dust suppression increases by 20.0%; neutralization of carbon monoxide - 59.4%; neutralization of nitrogen oxides - 55.1%.
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Wang, Yilong, Philippe Ciais, Daniel Goll, Yuanyuan Huang, Yiqi Luo, Ying-Ping Wang, A. Anthony Bloom, et al. "GOLUM-CNP v1.0: a data-driven modeling of carbon, nitrogen and phosphorus cycles in major terrestrial biomes." Geoscientific Model Development 11, no. 9 (September 27, 2018): 3903–28. http://dx.doi.org/10.5194/gmd-11-3903-2018.
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Abstract. Global terrestrial nitrogen (N) and phosphorus (P) cycles are coupled to the global carbon (C) cycle for net primary production (NPP), plant C allocation, and decomposition of soil organic matter, but N and P have distinct pathways of inputs and losses. Current C-nutrient models exhibit large uncertainties in their estimates of pool sizes, fluxes, and turnover rates of nutrients, due to a lack of consistent global data for evaluating the models. In this study, we present a new model–data fusion framework called the Global Observation-based Land-ecosystems Utilization Model of Carbon, Nitrogen and Phosphorus (GOLUM-CNP) that combines the CARbon DAta MOdel fraMework (CARDAMOM) data-constrained C-cycle analysis with spatially explicit data-driven estimates of N and P inputs and losses and with observed stoichiometric ratios. We calculated the steady-state N- and P-pool sizes and fluxes globally for large biomes. Our study showed that new N inputs from biological fixation and deposition supplied >20 % of total plant uptake in most forest ecosystems but accounted for smaller fractions in boreal forests and grasslands. New P inputs from atmospheric deposition and rock weathering supplied a much smaller fraction of total plant uptake than new N inputs, indicating the importance of internal P recycling within ecosystems to support plant growth. Nutrient-use efficiency, defined as the ratio of gross primary production (GPP) to plant nutrient uptake, were diagnosed from our model results and compared between biomes. Tropical forests had the lowest N-use efficiency and the highest P-use efficiency of the forest biomes. An analysis of sensitivity and uncertainty indicated that the NPP-allocation fractions to leaves, roots, and wood contributed the most to the uncertainties in the estimates of nutrient-use efficiencies. Correcting for biases in NPP-allocation fractions produced more plausible gradients of N- and P-use efficiencies from tropical to boreal ecosystems and highlighted the critical role of accurate measurements of C allocation for understanding the N and P cycles.
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Guan, Wei, Hua Zhao, Zhibo Ban, and Tiejian Lin. "Exploring alternative combustion control strategies for low-load exhaust gas temperature management of a heavy-duty diesel engine." International Journal of Engine Research 20, no. 4 (February 7, 2018): 381–92. http://dx.doi.org/10.1177/1468087418755586.
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The employment of aftertreatment systems in modern diesel engines has become indispensable to meet the stringent emissions regulations. However, a minimum exhaust gas temperature of approximately 200 °C must be reached to initiate the emissions control operations. Low-load engine operations usually result in relatively low exhaust gas temperature, which lead to reduced or no exhaust emissions conversion. In this context, this study investigated the use of different combustion control strategies to explore the trade-off between exhaust gas temperature, fuel efficiency, and exhaust emissions. The experiments were performed on a single-cylinder heavy-duty diesel engine at a light load of 2.2 bar indicated mean effective pressure. Strategies including the late intake valve closing timing, intake throttling, late injection timing (Tinj), lower injection pressure (Pinj), and internal exhaust gas recirculation and external exhaust gas recirculation were investigated. The results showed that the use of external exhaust gas recirculation and lower Pinj was not effective in increasing exhaust gas temperature. Although the use of late Tinj could result in higher exhaust gas temperature, the delayed combustion phase led to the highest fuel efficiency penalty. Intake throttling and internal exhaust gas recirculation allowed for an increase in exhaust gas temperature at the expense of higher fuel consumption. In comparison, late intake valve closure strategy achieved the best trade-off between exhaust gas temperature and net indicated specific fuel consumption, increasing the exhaust gas temperature by 52 °C and the fuel consumption penalty by 5.3% while reducing nitrogen oxide and soot emissions simultaneously. When the intake valve closing timing was delayed to after −107 crank angle degree after top dead centre, however, the combustion efficiency deteriorated and the HC and CO emissions were significantly increased. This could be overcome by combining internal exhaust gas recirculation with late intake valve closure to increase the in-cylinder combustion temperature for a more complete combustion. The results demonstrated that the ‘late intake valve closure + internal exhaust gas recirculation’ strategy can be the most effective means, increasing the exhaust gas temperature by 62 °C with 4.6% fuel consumption penalty. Meanwhile, maintaining high combustion efficiency as well as low HC and CO emissions of diesel engines.
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Barłóg, Przemysław, Remigiusz Łukowiak, and Lukáš Hlisnikovský. "Band Phosphorus and Sulfur Fertilization as Drivers of Efficient Management of Nitrogen of Maize (Zea mays L.)." Plants 11, no. 13 (June 23, 2022): 1660. http://dx.doi.org/10.3390/plants11131660.
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Increasing the efficiency of nitrogen use (NUE) from mineral fertilizers is one of the most important priorities of modern agriculture. The objectives of the present study were to assess the role of different nitrogen (N), phosphorus (P) and sulfur (S) rates on maize grain yield (GY), crop residue biomass, NUE indices, N concentration in plants during the growing season, N management indices and to select the most suitable set of NUE indicators. The following factors were tested: band application of di-ammonium phosphate and ammonium sulphate mixture (NPS fertilizer at rates 0, 8.7, 17.4, 26.2 kg ha−1 of P) and different total N rates (0, 60, 120, 180 kg ha−1 of N). In each year of the study, a clear trend of increased GY after NP(S) band application was observed. A particularly positive influence of that factor was confirmed at the lowest level of N fertilization. On average, the highest GY values were obtained for N2P3 and N3P1 treatments. The total N uptake and NUE indices also increased after the band application. In addition, a trend of improved N remobilization efficiency and the N contribution of remobilized N to grain as a result of band application of NP(S) was observed. Among various NUE indices, internal N utilization efficiency (IE) exhibited the strongest, yet negative, correlation with GY, whereas IE was a function of the N harvest index.
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Rawal, Nabin, Keshab Raj Pande, Renuka Shrestha, and Shree Prasad Vista. "Nutrient Use Efficiency Indices in Maize Hybrid as A Function of Various Rates of NPK in Mid Hills of Nepal." Turkish Journal of Agriculture - Food Science and Technology 9, no. 12 (December 26, 2021): 2278–88. http://dx.doi.org/10.24925/turjaf.v9i12.2278-2288.4637.
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Field experiments were conducted to evaluate yield and nutrient use efficiency in maize in response to various rates of nitrogen (N), phosphorus (P) and potassium (K) in silty clay loam soil of Khumaltar, Nepal during 2019 and 2020. Three factorial randomized complete block designs with 27 treatment combinations were used in experiments, which were repeated three times. Three factors were N levels (150, 180, 210 N kg ha-1), P levels (40, 60, 80 P2O5 kg ha-1), and K levels (40, 60, 80 K2O kg ha-1). The results recommend to revise fertilizer dose since N210 kg ha-1 and K2O 80 kg/ha were optimum for increased maize production with grain yields of 10.95 t ha-1 and 10.54 t ha-1, respectively. Partial factor productivity, partial nutrient budget, internal efficiency, physiological efficiency, recovery efficiency, and agronomic efficiency of NPK for hybrid maize were mostly influenced by nutrient levels. Application of higher rate of P and K fertilizer improved maize N efficiencies, and case was valid for P and K efficiencies. Maize was more responsive to N and K fertilizer and lower rate of P application limited efficient use of applied N and K. To increase overall NUE, we recommend to revise dose of fertilizer for hybrid maize under mid hill condition of Nepal.
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Prescott, Cindy E., John P. Corbin, and Dennis Parkinson. "Biomass, productivity, and nutrient-use efficiency of aboveground vegetation in four Rocky Mountain coniferous forests." Canadian Journal of Forest Research 19, no. 3 (March 1, 1989): 309–17. http://dx.doi.org/10.1139/x89-046.
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Aboveground biomass, annual production, and internal nitrogen and phosphorus dynamics of vegetation were compared among a 90-year-old Pinuscontorta Loudon forest, a 120-year-old Piceaglauca (Moench) Voss–P. contorta forest, a 350-year-old Piceaengelmannii Parry ex Engelm.–Abieslasiocarpa (Hook.) Nutt. forest, and a 13-year-old P. contorta stand in the Rocky Mountains of southwestern Alberta. Aboveground biomass of vegetation ranged from 109 to 203 t•ha−1, while aboveground net primary productivity ranged from 4.4 to 5.3 t•ha−1•year−1 in the mature forests. Approximately 30% of the N and 20–40% of the P in ground vegetation were reabsorbed during senescence; 40–50% of the N and 50–80% of the P were reabsorbed from senescing tree foliage. Annual uptake of nutrients (production minus reabsorption) was between 1.8 and 2.2 g•m−2•year−1 for N and 0.2–0.4 g•m−2•year−1 for P. Efficiency of nutrient use (milligrams of new biomass produced per milligram of nutrient taken up in 1 year) ranged from 249 to 262 for N and 1604 to 2355 for P in the mature forests, and 72 and 642, respectively, in the young pine stand. Both N and P were used very efficiently in the pine forest and relatively inefficiently in the spruce–pine forest, reflecting differences in the inherent nutrient-use efficiency of these tree species. In the spruce–fir forest, N was used less efficiently and P more efficiently than in other forests, in response to lower phosphorus availability in this forest. Differences in nutrient-use efficiency of vegetation were related to differences in the amount of biomass produced per unit amount of N or P taken up, and not to differences in efficiency of N or P reabsorption.
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Palikhel, Laxman, Rupesh Lal Karn, Suman Aryal, and Barsha Neupane. "Effect of Natural and Synthesized Oil Blends with Diesel by Volume on Lubrication and Performance of Internal Combustion Engine." Journal of Innovations in Engineering Education 3, no. 1 (March 31, 2020): 107–14. http://dx.doi.org/10.3126/jiee.v3i1.34331.
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Use of ultra-low sulfur diesel leads to improve emission but it has negative impact on lubrication. Poor lubrication leads to damage the cylinder parts and piston rings. For proper lubrication in ultra-low sulfur diesel, anti-wear agent, corrosion & Rust inhibitor, metal deactivator, Anti-oxidant, Pour point depressant, seal swell agent, viscosity improver and other are used. Viscosity improver such as polymers and copolymers of methacrylates, butadiene olefins and alkylated styrenes reduce the rate of viscosity change with temperature, metal deactivator are organic complexes containing nitrogen or sulphur, amines, sulphides and phosphites reduce catalytic effect on metals on oxidation rate, anti-wear agent such as Zinc dithiophosphates, organic phosphates and acid phosphates reduces friction and wear and prevent scoring and seizure. In this paper comparison of 5% blend of commercially available synthesized lubricating oil mixed with pure diesel by volume and 5% blend of transesterified Jatropha with pure diesel by volume is investigated. It is found that for the same brake power, indicated power provided by 5% blend of transesterified Jatropha is lower than 5% blend of lubricating oil. The friction loss for 5% blend of transesterified Jatropha is lower than 5% blend of lubricating oil. Throughout the load specific fuel consumption of 5% blend of transesterified Jatropha is lower than 5% blend of lubricating oil except at low load (i.e. before 1.5kg). Other performance parameters such as indicated thermal efficiency, brake thermal efficiency, volumetric efficiency and mechanical efficiency also support the fact that 5% blend of transesterified Jatropha shows a better performance characteristics than 5% blend of lubricating oil.
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Lopes, Marta S., Salvador Nogués, and José L. Araus. "Nitrogen source and water regime effects on barley photosynthesis and isotope signature." Functional Plant Biology 31, no. 10 (2004): 995. http://dx.doi.org/10.1071/fp04031.
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Water stress and nitrogen (N) availability are the main constraints on barley (Hordeum vulgare L.) yield in Mediterranean conditions. Here we studied the combined effects of N source and water regime (WR) on plant growth, photosynthesis and carbon isotope discrimination (Δ13C) in barley grown under controlled conditions. The effects of these conditions on plant N isotope discrimination against the fertiliser (Δ15N) was also examined to assess whether the natural variation in plant N isotope composition is a reliable indicator of N nutrition. Six experimental treatments were established with three nutrient solutions containing ammonium (NH4+), nitrate (NO3–) or a mixture of the two (NH4+ : NO3–), each either well watered or moderately water stressed. The NH4+ : NO3– treatment resulted in the greatest biomass accumulation and photosynthetic capacity in both WRs. The NH4+ plants showed accelerated phenology and depressed growth. They also had the lowest photosynthetic rates in both WRs. This effect was mainly due to stomatal closure, while electron transport and carboxylation capacity of leaves were less affected. Consistent with lower stomatal conductance, leaf Δ13C was lower in plants that received NH4+, indicating higher water use efficiency (WUE) not only when irrigated, but also under water stress. In addition, leaf Δ13C and photosynthetic N use efficiency (PNUE) correlated positively with each other and with shoot biomass in both WRs. However, NO3– treatment produced the greatest Δ15N, which was higher in leaves than in roots. Leaf Δ15N was decreased by water stress only in plants in the NO3– treatment. We conclude that leaf Δ13C is an adequate trait to assess the differences in growth, photosynthetic activity and WUE caused by distinct N sources. However, the usefulness of natural abundance of 15N in plant tissue as a nitrogen source marker is restricted by the effect of WR and internal plant fractionation, at least for plants that received NO3–.
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White, Sarah A., Milton D. Taylor, Stewart L. Chandler, Ted Whitwell, and Stephen J. Klaine. "Remediation of Nitrogen and Phosphorus from Nursery Runoff during the Spring via Free Water Surface Constructed Wetlands." Journal of Environmental Horticulture 28, no. 4 (December 1, 2010): 209–17. http://dx.doi.org/10.24266/0738-2898-28.4.209.
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Abstract Agricultural operations face increasing pressure to remediate runoff to reduce deterioration of surface water quality. Some nursery operations use free water surface constructed wetland systems (CWSs) to remediate nutrient-rich runoff. Our objectives were twofold, first to examine the impact of two hydraulic retention times (HRT, 3.5 and 5.5 day) on CWS performance, and second to determine if increased nutrient loading from internal CWS and nursery sources during the spring contributed to nutrient export in excess of regulatory limits. We quantified nutrient loading and removal efficiency in a free water surface CWS from late winter through late spring over three years and monitored various water quality parameters. Total nitrogen in runoff was reduced from 20.6 ± 2.8 mg·liter−1 (ppm) to 4.1 ± 1.3 mg·liter−1 (ppm) nitrogen after CWS treatment. Phosphorus dynamics in the CWS were more variable and unlike nitrogen dynamics were not consistently influenced by water temperature and hydraulic loading rate. Phosphorus concentrations were reduced from 1.7 ± 0.8 mg·liter−1 (ppm) PO4-P in influent to 1.2 ± 0.6 mg·liter−1 (ppm) PO4-P in CWS effluent, but substantial variability existed among years in both phosphorus loading and removal rates. The CWS was able to efficiently remediate nitrogen even under high spring loading rates.
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Karczewski, Mirosław, Leszek Szczęch, Filip Polak, and Szymon Brodowski. "Analysis of Electric Vehicles Efficiency and their Influence on Environmental Pollution." Journal of KONES 26, no. 4 (December 1, 2019): 97–104. http://dx.doi.org/10.2478/kones-2019-0095.
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AbstractElectric vehicles are increasingly present on the roads of the whole world. They have the opinion of ecological vehicles, not polluting the environment. Society is more and more often persuaded to buy electric cars as an environmentally friendly solution but is this for sure? Electric cars need quite a lot of electricity accumulated in batteries to drive on a long range. During the charging process, this energy is obtained from the electricity network, to where it is supplied by power plant. Electricity production from renewable sources is a privilege for the rare. However, electric cars are charged from the electricity grid, which in large part energy comes from non-renewable fuels. The efficiency of energy production in power plants and the energy transmission and conversion chain causes that only part of the energy produced in this way goes to the vehicle’s wheels. Although the power plants are equipped with more and more efficient exhaust gas cleaning systems, they do not clean them up to 100%. Sulphur, nitrogen, mercury and heavy metals remain in the exhaust. The article is an attempt to answer the question whether the total emission of toxic components associated with the use of an electric vehicle is not bigger than in a traditional internal combustion engine.
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Zhao, Shuang, and Cui Ping Wang. "Simultaneous COD and Nitrogen Removal in Up-Flow Microaerobic-Oxic (M/O) Process for Domestic Wastewater Treatment." Advanced Materials Research 838-841 (November 2013): 2739–44. http://dx.doi.org/10.4028/www.scientific.net/amr.838-841.2739.
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A novel process for improving the energy use and treatment efficiency of the biological nitrogen removal process, up-flow microaerobic-oxic (M/O) process which is composed of up-flow micro-aerobic and aeration was proposed based on a laboratory scale for domestic wastewater treatment, the dissolved oxygen (DO) in up-flow micro-aerobic was in the range of (0~0.5) mg/L. The M/O process performance under different hydraulic retention time (HRT) and Internal return ratio (r) was investigated. Under the optimal conditions, the average removal efficiencies of chemical oxygen demand (COD), total nitrogen (TN) and ammonium nitrogen (NH4+-N) were 89.1%, 64.1%, and 96.6 % with effluent concentrations of COD, TN and NH4+-N less than 50,15 and 8mg/L, respectively. The distribution of sludge particles diameter and microbial activity of activated sludge were also measured, the mean particle diameter was in the range of 180~250μm and the SOURT was 13.11 mgO2/(gMLVSSh). Up-flow micro-aerobic (M/O) reactor has the advantages of more stable performance and better resistance to the load shock than the conventional A/O process within continuous running period of 130 days.
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Santana, Elisson Alves, Francisco Eduardo dos Santos Gomes, Jackson Teixeira Lobo, Alberto de Andrade Soares Filho, Ítalo Herbert Lucena Cavalcante, and Vespasiano Borges de Paiva Neto. "Leaf gas exchange and chlorophyll index in guava fertirrigated with bovine biofertilizer and nitrogen." Research, Society and Development 9, no. 9 (August 30, 2020): e588997606. http://dx.doi.org/10.33448/rsd-v9i9.7606.
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The objective of this work was to evaluate the influence of fertirrigation with nitrogen and liquid bovine biofertilizer on gas exchange and leaf chlorophyll index of 'paluma' guava (Psidium guajava L.). The experimental design was randomized blocks with treatments distributed in a factorial arrangement (2 × 4) referring to mineral fertilizing with N (50% and 100% of N recommended) and biofertilizer concentrations (0, 2.5, 5.0 and 7.5% of the fertirrigated volume). Variables evaluated were chlorophyll a (Chl a), chlorophyll b (Chl b), total chlorophyll indexes (Chltotal), internal CO2 concentration (Ci), stomatal conductance (gs), transpiration (E), net photosynthesis (A), instant carboxylation efficiency (iCE) and water use efficiency (WUE). The biofertilizer significantly affected Chl a, Chl b, Chltotal, A, gs and E, with quadratic polynomial adjustment of the results. However, there was no effect of N fertilization and interaction between the factors. Maximum index of Chltotal was 32.31 obtained with the estimated dose of 3.8% of the biofertilizer; while A, gs and E presented maximum responses of 19.09 µmol of CO2 m-2 s-1, 0.28 mol of H2O m-2 s-1 and 4.93 mmol of H2O m-2 s-1, with estimated doses of 3.6%, 3.6%, and 3.7%, respectively. Generally, liquid bovine biofertilizer applied via fertirrigation affects positively the photosynthetic responses in 'paluma' guava, however, with decreasing effects for doses above 3.8%.
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Lemoine, C., M. Payraudeau, and J. Meinhold. "Aeration control for simultaneous nitrification-denitrification in a biological aerated filter using internal model approach." Water Science and Technology 54, no. 8 (October 1, 2006): 129–36. http://dx.doi.org/10.2166/wst.2006.753.
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Experience has shown that simultaneous nitrification/denitrification in a biological aerated filter is possible. However these systems react very sensitively to the aeration control strategies applied. Poorly adapted control strategies induce a strong decrease in treatment efficiency. A new control strategy for simultaneous N/DN is developed. The strategy proposed makes use of ammonia measurements and the inlet and outlet: a Feedback/Feedforward block. Passing by a calculation of the load to be eliminated, an estimation of the air flow velocity to be applied is carried out dynamically. A retroactive loop corrects this prediction in order to reach exactly the desired set point. This control approach has been implemented and tested at pilot plant scale for a period of 18 months. The pilot plant consists of two coupled BAF cells, reflecting closely industrial scale situations. Comparative studies reveal clearly the improved performance of the developed FF/FB control strategy compared to classical controllers. The benefits include 5% increase in nitrogen removal performance and a reduction of 15 to 20% in air requirement, offering a rapid return of investment costs.
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Nawar, Ali I., Heba S. A. Salama, and Hassan E. Khalil. "Additive intercropping of sunflower and soybean to improve yield and land use efficiency: Effect of thinning interval and nitrogen fertilization." Chilean journal of agricultural research 80, no. 2 (June 2020): 142–52. http://dx.doi.org/10.4067/s0718-58392020000200142.
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Gracz, Weronika, Damian Marcinkowski, Wojciech Golimowski, Filip Szwajca, Maria Strzelczyk, Jacek Wasilewski, and Paweł Krzaczek. "Multifaceted Comparison Efficiency and Emission Characteristics of Multi-Fuel Power Generator Fueled by Different Fuels and Biofuels." Energies 14, no. 12 (June 8, 2021): 3388. http://dx.doi.org/10.3390/en14123388.
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The negative effect of liquid and gaseous fuel combustion is toxic gases (i.e., carbon and nitrogen oxides NOx) and particulate matter (PM) formation. The content of harmful and toxic components of exhaust gases is strongly dependent on the quality and type of burnt fuel. Experimental research is required to verify the use of current technical and technological solutions for the production of electricity on farms, using various types of conventional fuels and biofuels. The aim of the current research was to comprehensively verify the use of commonly available fuels and biofuels without adapting the internal combustion engine. Gaseous fuels—propane-butane mixture (LPG), compressed natural gas (CNG) and biogas (BG)—were added to liquid fuels—methyl esters of higher fatty acids (RME) and diesel fuel (DF)—in six different power configurations to evaluate the effect on the emission of toxic gases: carbon monoxide (CO), nitric oxide (NO), nitric dioxide (NO2) and particulate matter (PM), and the efficiency of fuel conversion. The use of RME in various configurations with gaseous fuels increased the emission of oxides and reduced the emission of PM. Increasing the share of LPG and CNG significantly increased the level of NO emissions. The use of gaseous fuels reduced the efficiency of the generator, particularly in the case of co-firing with DF. For medium and high loads, the lowest decrease in efficiency was recorded for the RME configuration with BG. Taking into account the compromise between individual emissions and the configuration of RME with BG, the most advantageous approach is to use it in power generators.