Academic literature on the topic 'Chemical inputs'
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Journal articles on the topic "Chemical inputs"
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Kalala, Daniel M., Victor Shitumbanuma, Noah Adamtey, and Benson H. Chishala. "Organic Inputs and Chemical Fertilizer on Carbon Mineralization From Two Ultisols." Journal of Agricultural Science 12, no. 11 (October 15, 2020): 223. http://dx.doi.org/10.5539/jas.v12n11p223.
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There are challenges that limit the use of organic inputs for soil fertility management. Amongst them is the limited knowledge of factors that affect rates of decomposition and nutrient release from different organic inputs. A study was conducted on surface soil samples of two Ultisols to determine factors affecting carbon (C) mineralization from selected organic inputs. A loamy sand (LS) from a Kandiustult and a sandy clay loam (SCL) from a Paleustult were used. Fine earth fractions of the soils mixed with organic inputs with and without chemical fertilizer were incubated for 13 weeks and the CO2 evolved was measured. Organic inputs used were biomasses of Cajanus cajan, Tephrosia vogelii, Crotalaria juncea, Mucuna pruriens, a mixture of native grasses and shrubs and composted cattle manure. The latter two inputs are traditionally used by farmers, while the leguminous plants were recommended by scientists. Treatments with chemical fertilizer only, representing the conventional farming practice, and a control with soil alone were included. Addition of organic inputs with or without fertilizer increased total CO2 emissions by 81 to 129% on the LS and by 18 to 34% on the SCL. Adding chemical fertilizer significantly (p < 0.05) increased C mineralization rate constant (k) by 116% on the LS and 48% on the SCL. The mean residence time of organic carbon from treatments grouped by input type followed the order: Control > Traditional > Legumes > Conventional on both soils. In general, the k on the LS was double that on the SCL. The type of organic input, soil texture and application of chemical fertilizer significantly affected C mineralization rates from the soils.
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Zhang, Sheng, Ming Bao, and Masahiko Yamaguchi. "Thermal Input/Concentration Output Systems Processed by Chemical Reactions of Helicene Oligomers." Reactions 3, no. 1 (January 25, 2022): 89–117. http://dx.doi.org/10.3390/reactions3010008.
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This article describes thermal input/concentration output systems processed by chemical reactions. Various sophisticated thermal inputs can be converted into concentration outputs through the double-helix formation of helicene oligomers exhibiting thermal hysteresis. The inputs include high or low temperature, cooling or heating state, slow or fast cooling state, heating state, and cooling history. The chemical basis for the properties of the chemical reactions includes the reversibility out of chemical equilibrium, sigmoidal relationship and kinetics, bistability involving metastable states, positive feedback by self-catalytic chemical reactions, competitive chemical reactions, and fine tunability for parallel processing. The interfacing of concentration outputs in other systems is considered, and biological cells are considered to have been utilizing such input/output systems processed by chemical reactions.
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Boxall, Alistair, Anthony Hardy, Sabine Beulke, Tatiana Boucard, Laura Burgin, Peter Falloon, Philip Haygarth, et al. "Impacts of climate change on indirect human exposure to pathogens and chemicals from agriculture." Ciência & Saúde Coletiva 15, no. 3 (May 2010): 743–56. http://dx.doi.org/10.1590/s1413-81232010000300017.
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Climate change is likely to affect the nature of pathogens/ chemicals in the environment and their fate and transport. We assess the implications of climate change for changes in human exposures to pathogens/chemicals in agricultural systems in the UK and discuss the effects on health impacts, using expert input and literature on climate change; health effects from exposure to pathogens/chemicals arising from agriculture; inputs of chemicals/pathogens to agricultural systems; and human exposure pathways for pathogens/chemicals in agricultural systems. We established the evidence base for health effects of chemicals/pathogens in the agricultural environment; determined the potential implications of climate change on chemical/pathogen inputs in agricultural systems; and explored the effects of climate change on environmental transport and fate of various contaminants. We merged data to assess the implications of climate change in terms of indirect human exposure to pathogens/chemicals in agricultural systems, and defined recommendations on future research and policy changes to manage adverse increases in risks.
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Zhang, Lu, Wesley A. Whitfield, and Lei Zhu. "Unimolecular binary half-adders with orthogonal chemical inputs." Chemical Communications, no. 16 (2008): 1880. http://dx.doi.org/10.1039/b719644j.
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Magri, David C., Gregory D. Coen, Robert L. Boyd, and A. Prasanna de Silva. "Consolidating molecular AND logic with two chemical inputs." Analytica Chimica Acta 568, no. 1-2 (May 2006): 156–60. http://dx.doi.org/10.1016/j.aca.2005.11.073.
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Chandler, Margaret J., Jianhua Zhang, Chao Qin, Yu Yuan, and Robert D. Foreman. "Intrapericardiac injections of algogenic chemicals excite primate C1-C2 spinothalamic tract neurons." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 279, no. 2 (August 1, 2000): R560—R568. http://dx.doi.org/10.1152/ajpregu.2000.279.2.r560.
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Extracellular potentials of 38 C1-C2 spinothalamic tract (STT) neurons in anesthetized monkeys ( Macaca fascicularis) were examined for responses to intrapericardiac injections of an algogenic chemical mixture (adenosine, 10−3 M; bradykinin, prostaglandin E2, serotonin, histamine, each 10−5 M). Chemical stimulation of cardiac/pericardiac receptors increased activity of 21 cells, decreased activity of 5 cells, and did not change activity of 12 cells. Cells excited by chemical stimuli received input from noxious mechanical stimulation of somatic fields; most receptive fields included the neck, inferior jaw, or head areas. Nerve ablations in 11 cells excited by intrapericardiac chemicals showed that cardiac input activated by algogenic chemicals traveled primarily in vagal afferent fibers to C1-C2 segments; phrenic or cardiopulmonary sympathetic inputs were predominant in 2 of 11 cells. These results supported the concept that activation of cardiac vagal afferents might lead to the production of referred pain sensation in somatic fields innervated from high cervical segments.
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Shenshin, Vasily A., Camille Lescanne, Guillaume Gines, and Yannick Rondelez. "A small-molecule chemical interface for molecular programs." Nucleic Acids Research 49, no. 13 (July 5, 2021): 7765–74. http://dx.doi.org/10.1093/nar/gkab470.
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Abstract In vitro molecular circuits, based on DNA-programmable chemistries, can perform an increasing range of high-level functions, such as molecular level computation, image or chemical pattern recognition and pattern generation. Most reported demonstrations, however, can only accept nucleic acids as input signals. Real-world applications of these programmable chemistries critically depend on strategies to interface them with a variety of non-DNA inputs, in particular small biologically relevant chemicals. We introduce here a general strategy to interface DNA-based circuits with non-DNA signals, based on input-translating modules. These translating modules contain a DNA response part and an allosteric protein sensing part, and use a simple design that renders them fully tunable and modular. They can be repurposed to either transmit or invert the response associated with the presence of a given input. By combining these translating-modules with robust and leak-free amplification motifs, we build sensing circuits that provide a fluorescent quantitative time-response to the concentration of their small-molecule input, with good specificity and sensitivity. The programmability of the DNA layer can be leveraged to perform DNA based signal processing operations, which we demonstrate here with logical inversion, signal modulation and a classification task on two inputs. The DNA circuits are also compatible with standard biochemical conditions, and we show the one-pot detection of an enzyme through its native metabolic activity. We anticipate that this sensitive small-molecule-to-DNA conversion strategy will play a critical role in the future applications of molecular-level circuitry.
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Smith, Stephen, John Delaney, Michael Robinson, and Martin Rice. "Targeting Chemical Inputs and Optimising HTS for Agrochemical Discovery." Combinatorial Chemistry & High Throughput Screening 8, no. 7 (November 1, 2005): 577–87. http://dx.doi.org/10.2174/138620705774575346.
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Held, David W., and Daniel A. Potter. "Prospects for Managing Turfgrass Pests with Reduced Chemical Inputs." Annual Review of Entomology 57, no. 1 (January 7, 2012): 329–54. http://dx.doi.org/10.1146/annurev-ento-120710-100542.
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Liu, Moucheng, Cheng Chen, Lun Yang, Qingwen Min, and Ying Xiong. "Agricultural eco-compensation may not necessarily reduce chemical inputs." Science of The Total Environment 741 (November 2020): 139847. http://dx.doi.org/10.1016/j.scitotenv.2020.139847.
Full textDissertations / Theses on the topic "Chemical inputs"
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Watts, Adrian J. "The monitoring and control of chemical inputs to arable farming systems." Thesis, Cranfield University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443750.
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Aroh, Kosisochukwu C. "Determination of optimal conditions and kinetic rate parameters in continuous flow systems with dynamic inputs." Thesis, Massachusetts Institute of Technology, 2018. https://hdl.handle.net/1721.1/121815.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemical Engineering, 2019Cataloged from PDF version of thesis.
Includes bibliographical references (pages 171-185).
.The fourth industrial revolution is said to be brought about by digitization in the manufacturing sector. According to this understanding, the third industrial revolution which involved computers and automation will be further enhanced with smart and autonomous systems fueled by data and machine learning. At the research stage, an analogous story is being told in how automation and new technologies could revolutionize a chemistry laboratory. Flow chemistry is a technique that contrast with traditional batch chemistry in one aspect as a method that facilitates process automation and in small scales, delivers process improvements such as high heat and mass transfer rates. In addition to flow chemistry, analytical tools have also greatly improved and have become fully automated with potential for remote control. Over the past decade, work utilizing optimization techniques to find optimal conditions in flow chemistry have become more prevalent.
In addition, the scope of reactions performed in these systems have also increased. In the first part of this thesis, the construction of a platform capable of performing a wide range of these reactions on the lab scale is discussed. This platform was built with the capability of performing global optimizations using steady state experiments. The rest of the thesis concerns generating dynamic experiments in flow systems and using these conditions to gain more information about a reaction. The ability to use dynamic experiments to accurately determine reaction kinetics is first detailed. Through these experiments we found that only two orthogonal experiments were needed to sample the experimental space. After this an algorithm that utilizes dynamic experiments for kinetic parameter estimation problems is described. The approach here was to use dynamic experiments to first quickly sample the design space to get a reasonable estimate of the kinetic parameters.
Then steady state optimal design of experiments were used to fine tune these estimates. We observed that after initial orthogonal experiments only three more conditions were needed for accurate estimates of the multi-step reaction example. In a similar fashion, an algorithm for reaction optimization that relies on dynamic experiments is also described. The approach here extended that of adaptive response surface methodology where dynamic orthogonal experiments were performed in place of steady state experiments. When compared to steady state optimizations of multi-step reactions, a reduction by half in time needed to locate the optimum is observed. Finally, the potential issues that arise when using transient experiments in automated systems for reaction analysis are addressed. These issues include dispersion, sampling rate, reactor sizes and the rate of change of transients.
These results demonstrate a way with which technological innovation could further revolutionize the chemistry laboratory. By combining machine learning, clouding computing and efficient, high information experiments reaction data could be quickly collected, and the information gained could be maximized for future predictions or optimizations.
by Kosisochukwu C. Aroh.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Chemical Engineering
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Cachada, Anabela Ferreira de Oliveira. "Organic contaminants in urban soils: major inputs and potential risks." Doctoral thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/14130.
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Doutoramento em QuímicaUrban soil quality may be severely affected by hydrophobic organic contaminants (HOCs), impairing environmental quality and human health. A comprehensive study was conducted in two contrasting Portuguese urban areas (Lisbon and Viseu) in order to assess the levels and potential risks of these contaminants, to identify sources and study their behaviour in soils. The concentrations of HOCs were related to the size of the city, with much higher contamination levels observed in Lisbon urban area. Source apportionment was performed by studying the HOCs profiles, their relationship with potentially toxic elements and general characteristics of soil using multivariate statistical methods. Lisbon seems to be affected by nearby sources (traffic, industry and incineration processes) whereas in Viseu the atmospheric transport may be playing an important role. In a first tier of risk assessment (RA) it was possible to identify polycyclic aromatic hydrocarbons (PAHs) in Lisbon soils as a potential hazard. The levels of PAHs in street dusts were further studied and allowed to clarify that traffic, tire and pavement debris can be an important source of PAHs to urban soils. Street dusts were also identified as being a potential concern regarding human and environmental health, especially if reaching the nearby aquatic bodies. Geostatistical tools were also used and their usefulness in a RA analysis and urban planning was discussed. In order to obtain a more realistic assessment of risks of HOCs to environment and human health it is important to evaluate their available fraction, which is also the most accessible for organisms. Therefore, a review of the processes involved on the availability of PAHs was performed and the outputs produced by the different chemical methods were evaluated. The suitability of chemical methods to predict bioavailability of PAHs in dissimilar naturally contaminated soils has not been demonstrated, being especially difficult for high molecular weight compounds. No clear relationship between chemical and biological availability was found in this work. Yet, in spite of the very high total concentrations found in some Lisbon soils, both the water soluble fraction and the body residues resulting from bioaccumulation assays were generally very low, which may be due to aging phenomena. It was observed that the percentage of soluble fraction of PAHs in soils was found to be different among compounds and mostly regulated by soil properties. Regarding bioaccumulation assays, although no significant relationship was found between soil properties and bioavailability, it was verified that biota-to-soil bioaccumulation factors were sample dependent rather than compound dependent. In conclusion, once the compounds of potential concern are targeted, then performing a chemical screening as a first tier can be a simple and effective approach to start a RA. However, reliable data is still required to improve the existing models for risk characterization.
A qualidade dos solos urbanos pode ser afetada por contaminantes orgânicos hidrofóbicos (HOCs), prejudicando a saúde ambiental e humana. Este trabalho consistiu em estudar duas áreas urbanas contrastantes (Lisboa e Viseu), com o objetivo de avaliar os níveis de HOCs nos solos e os seus potenciais riscos para a saúde humana e para o ambiente. Pretendia-se ainda identificar as fontes e estudar o comportamento destes contaminantes no solo. Foi possível relacionar as concentrações de HOCs com o tamanho da cidade, sendo os níveis de contaminação muito mais elevados em Lisboa. A identificação das fontes destes contaminantes foi feita através do estudo dos respetivos perfis e da relação com elementos potencialmente tóxicos, utilizando métodos estatísticos multivariados. Lisboa parece ser afetada por fontes próximas (tráfego, indústria e incineração) enquanto em Viseu o transporte atmosférico aparenta ter um papel mais importante. Num primeiro nível da avaliação de risco (RA), foi possível identificar os hidrocarbonetos aromáticos policíclicos (PAHs) nos solos de Lisboa como um perigo potencial. Os níveis de PAHs em poeiras das ruas de Lisboa foram também estudados e permitiram clarificar que o tráfego e os detritos de pneus e de pavimento podem também ser uma importante fonte destes compostos. Utilizaram-se e discutiram-se ferramentas de geoestatística assim como a respetiva utilidade em RA e em planeamento urbano. De modo a obter uma avaliação mais realista dos riscos de HOCs é importante avaliar a fração disponível, que é também a mais acessível para os organismos. Deste modo, foi feita uma avaliação dos processos envolvidos na disponibilidade de PAHs e também dos resultados obtidos pelos diferentes métodos químicos. A adequação dos métodos químicos para prever a biodisponibilidade de PAHs em solos naturalmente contaminados ainda não foi demonstrada, sendo especialmente difícil para os compostos de elevado peso molecular. No presente trabalho também não foi possível estabelecer uma relação significativa entre a disponibilidade química e a biodisponibilidade. No entanto, apesar das elevadas concentrações totais encontradas em alguns solos de Lisboa, tanto a fração solúvel em água como os resíduos acumulados nos ensaios de bioacumulação foram, em geral, muito baixos, o que estará relacionado com os fenómenos de envelhecimento destes contaminantes nos solos. Observou-se que a fração solúvel de PAHs depende do composto em causa e é regulada pelas propriedades do solo. Apesar de não se terem observado correlações entre as propriedades do solo e a biodisponibilidade, observou-se que os fatores de bioacumulação dependem mais da amostra do que do composto. Em conclusão: após a identificação dos contaminantes de interesse uma avaliação química baseada nos teores totais pode ser uma abordagem eficaz no primeiro nível da RA, mas no entanto é necessário melhorar os modelos existentes para a caracterização do risco.
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Lange, Ian. "Investigating the effects of the 1990 Clean Air Act Amendments on inputs to coal-fired power plants /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/7421.
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Warby, Richard Ashley Frank. "The chemical response of surface waters and organic soils across the northeastern United States, following reduced inputs of acidic deposition 1984-2001 /." Related electronic resource:, 2007. http://proquest.umi.com/pqdweb?did=1342747271&sid=1&Fmt=2&clientId=3739&RQT=309&VName=PQD.
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Law, Audrey. "EVALUATING THE EFFECTS OF ORGANIC AND CONVENTIONAL INPUTS ON SOIL CHEMICAL AND BIOLOGICAL PROPERTIES IN A FOUR-YEAR VEGETABLE ROTATION AND THE INVESTIGATION OF SOIL MICROBIAL PROPERTIES ON PLANT GENE EXPRESSION." UKnowledge, 2009. http://uknowledge.uky.edu/gradschool_diss/704.
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The objective of this research was to determine the effects of conventional inputs on soil chemical and biological properties compared to organic systems in a four year vegetable rotation. Tillage and cover crops were the same in all treatments to avoid confounding factors often present in similar research. Additional experiments investigated plant gene expression in organic and conventional management systems and in soils with decreased microbial diversity. Experimental plots were prepared in the spring of 2004; four replications of three management treatments, organic, low-input and conventional, were arranged in a randomized complete block design. The rotation consisted of edamame soybean, sweet corn, fallow (pastured poultry in organic plots), and potatoes. Soil samples were taken in the spring and fall of each year, along with data for pest damage, weed control, yield and quality. Soil samples were analyzed for enzyme activity (maximum activity under substrate saturation) and basic soil chemical properties. Treatments were compared over time using 2-Way ANOVA. Multiplex terminal-restriction fragment length polymorphism (M-TRFLP) profiles of the soil microbial community were compared using Multiple Response Permutation Procedures (MRPP). Multi-way ANOVA detected significant treatment effects over time in total carbon, nitrogen, Mehlich III K, Exchangeable K and exchangeable Na (p=0.05). Many significant changes in soil properties over time could not be attributed to treatment effects. All treatments produced similar yields, indicating that successful organic production of these vegetables is possible in Kentucky. Input costs for organic were 37% higher than conventional, due to the cost of organic fertilizer. The organic system required nearly 50% more labor hours than conventional or low-input. The low-input system was the most cost effective, with 58% less input expenses than the conventional system. Microarray analysis of approximately 37,500 Glycine max transcripts did not show significant differences in the gene expression between plants grown organically and conventionally, in plots with significant soil chemical and microbial differences. An experiment in progress is investigating changes in plant gene expression using real time RT-PCR in tomatoes grown in autoclaved soil and native field soil.
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Thuto, Mosalagae. "Adaptive tracking for exothermic chemical reactors under input constraints." Thesis, University of Exeter, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323986.
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Cao, Yi. "Control structure selection for chemical processes using input-output controllability analysis." Thesis, University of Exeter, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296283.
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Baker, Rhoda. "Inclusion of input saturation in the design of dynamically operable plants." Master's thesis, University of Cape Town, 2000. http://hdl.handle.net/11427/5343.
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Bibliography: leaves 109-113.Dynamic operability reflects the quality with which a plant can be controlled using feedback, and is a function of both the design of the plant and its associated control system. A plant designed on the basis of steady-state considerations alone could exhibit poor dynamic characteristics, leading to a loss of economic performance and a reduced capacity to effectively handle safety and environmental constraints. This motivates the need for the development of quantitative techniques for dynamic operability assessment, as well as its incorporation into procedures for process plant design. Optimization-based approaches to dynamic operability assessment permit simultaneous consideration of performance-limiting factors of nonminimum phase characteristics, input constraints and model uncertainty, and also provide considerable flexibility in the choice of performance criteria, decision variables and constraints. Recent work has incorporated operability requirements as constraints within a single optimal plant design problem formulation (Mohideen et at., 1997; Bahri et at.,1996). Young and Swartz (1997) considered the rigorous inclusion of input saturation effects in optimizing control. Actuator saturation introduces discontinuities in the system model and, to avoid potential problems using a sequential optimization approach, two alternative formulations were proposed for solving the problem within a simultaneous solution framework. Input saturation discontinuities were handled by the introduction of slack variables and their inclusion in either bilinear or mixed-integer constraints resulting in a nonlinear or mixed-integer linear programming problem respectively. The formulations were applied to a linear system with dead time to find the economically optimal operating point for a controller with fixed structure and tunings when disturbance deviations are taken into account. It was shown that using a strictly linear controller in this case would lead to an overly conservative estimate of the feasible operating range and consequently, a suboptimal operating point.
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Safari, Mehdi. "The effect of energy input on flotation kinetics." Doctoral thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/28162.
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SYNOPSIS Energy/power input in a flotation cell is an important parameter which, if optimised, can increase the flotation rate. The optimum energy/power input within a flotation cell is still a matter of conjecture and there is a need for a better understanding of the effect of energy input on flotation kinetics. This study investigates the effect of energy/power input on flotation kinetics in an oscillating grid flotation cell (OGC). The OGC decouples the processes of solid suspension and bubble generation as well as producing relatively isotropic and homogeneous turbulence with zero mean flow. Due to this, oscillating grids provide a potentially ideal environment for investigating the effects of energy input on flotation kinetics, which cannot be achieved in a mechanical flotation cell. The first objective of this thesis was to determine the effect of energy/power input on the flotation kinetics of sulphide minerals (galena, pyrite & pentlandite) and oxide minerals (apatite & hematite) in a laboratory scale oscillating grid flotation cell. The second objective was to compare the results from the laboratory OGC to comparative studies in the flotation literature and to fundamental models for particle-bubble contacting. The third objective was to determine whether the experimental results from the laboratory OGC are consistent with those from a pilot-scale OGC operating on a platinum ore. Galena, pyrite, pentlandite (-150 μm), apatite (-650 μm) and hematite (-75 μm) were floated in the laboratory OGC at energy inputs from 0.1 to 5.0 W/kg, using 0.13, 0.24, 0.58 and 0.82 mm bubble sizes (d₁₀), and at three collector dosages. Platinum ore (-75 μm) was floated in the pilot-scale OGC at energy inputs from 0 to 2.5 W/kg, using 0.71 and 1.47 mm bubble sizes (d₁₀). The effect of energy input on flotation kinetics was interpreted through trends in experimental flotation rate constants, simulated flotation rate constants and attachment-detachment flotation rate constants. Here, simulated flotation rate constants were calculated using a literature fundamental model for flotation in turbulent systems. This model is based on suitable expressions for the collision frequency, collision efficiency, attachment efficiency and stability efficiency, Attachment-detachment flotation rate constants were calculated using a kinetic model which allows for the two separate processes of bubble-particle collision/attachment and detachment. This model is based on kinetic expressions using empirical correlations for the attachment and detachment rate constants. Experimental flotation results show that the effect of energy input on the flotation rate is strongly dependent on the particle size and particle density and less dependent on bubble size and contact angle. Flotation rates generally increase with increasing particle size, decreasing bubble size and increasing contact angle, as is commonly found in the literature. Increasing energy input generally leads to an increase in the flotation rate for fine particles, an optimum flotation rate for intermediate particles and a decrease in the flotation rate for coarse particles. The optimum in the flotation rate for minerals with higher density is at a lower energy input than that for lower density minerals. The changes (increases/decreases) in the flotation rate with increasing energy input are very large for most of the conditions, indicating that this is an important parameter in flotation. Pilot scale results generally support the trends observed in the laboratory OGC. These findings are attributed to the effect of energy/power input on bubble-particle collection which is a balance between two competing effects, those of bubble-particle collision/attachment and those of bubble-particle detachment. Increasing energy input generally leads to significant increases in the flotation rate of fine particles, due to increased bubble-particle collision/attachment. Increasing energy input generally leads to an optimum flotation rate for intermediate particles, due to a combination of increased bubble-particle collision/attachment and detachment. For coarse particles, increasing energy input leads to significant increases in bubble-particle detachment. The relationship between the flotation rate and energy input is often described as k ɛᴺ, in the absence of significant bubble-particle detachment. The typical values of N are in the range of 0.44-0.75 for theoretical studies and 0.7-1 for experimental studies. The values of N found in the current study are in the range of 0.7-1, which suggests that bubbleparticle collision/attachment has a stronger dependence on energy input than theory suggests. Simulated flotation results for fine particles compare well to the experimental data in terms of both trends and magnitude. This suggest that the turbulent collision model used is appropriate for fine particles. For intermediate particles there are differences between the simulated flotation rate constants and the experimental data, primarily in terms of trends. For coarse particles there are very large differences between simulated flotation rate constants and the experimental data. This is attributed to under prediction of the collision frequency/efficiency and incorrect prediction of the stability efficiency. Here, the stability efficiency is considered to be under predicted at low energy inputs and over predicted at high energy inputs. This suggests that the stability efficiency has a much stronger dependence on energy input than theory suggests. Attachment-detachment results show that the attachment rate constant has a stronger dependence on energy input than theory suggest, supporting finding from the experimental results and simulated results for coarser particles. In addition, the detachment rate constant has a much stronger dependence on energy input than theory suggests, supporting findings from both the experimental and simulated results. Based on the objectives of this study and literature reviewed, the following hypotheses were made at the outset 1) Increasing energy/power input will increase the rate of flotation of fine particles but will result in an optimum for intermediate and coarse particles. The position of this optimum will depend on the particle density, bubble size and contact angle. 2) Fundamental models based on the RMS turbulent velocity will be appropriate for describing flotation kinetics as turbulence in the oscillating grid cell is relatively homogeneous and isotropic and 3) Trends in flotation results for a laboratory and pilot-scale oscillating grid flotation cell will be comparable as the distribution of turbulence in OGCs at equivalent specific power inputs is scale independent. Hypothesis 1 was found to be valid for both fine and intermediate particles, but for coarse particles increasing energy input resulted in sharp decreases in the flotation rate. In addition, the increase in the flotation rate with increasing energy input was found to be more dependent on the particle size and particle density than the bubble size and contact angle. Hypothesis 2 was found to be valid for fine particles but not for intermediate or coarse particles. Here, it was found that the processes of bubble-particle collision/attachment and detachment have a stronger dependence on energy input than theory suggests. Hypothesis 3 was supported by general trends in results for the laboratory and pilot-scale oscillating grid flotation cells, but was not convincingly demonstrated.
Books on the topic "Chemical inputs"
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Swain, L. G. Second report on chemical sensitivity of B.C. lakes to acidic inputs. [B.C.]: Ministry of Environment and Parks, Province of British Columbia, 1987.
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Sp, Palaniappan, ed. Agricultural inputs and environment. Jodhpur: Scientific Publishers, 1995.
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United States. Congress. House. Committee on Government Operations. Low input farming systems: Benefits and barriers : seventy-fourth report. Washington: U.S. G.P.O., 1988.
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United States. Congress. House. Committee on Government Operations. Environment, Energy, and Natural Resources Subcommittee. Environmental and economic benefits of low-input farming: Hearing before a subcommittee of the Committee on Government Operations, House of Representatives, One Hundredth Congress, second session, April 28, 1988. Washington: U.S. G.P.O., 1989.
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United States. Congress. House. Committee on Government Operations. Environment, Energy, and Natural Resources Subcommittee. Environmental and economic benefits of low-input farming: Hearing before a subcommittee of the Committee on Government Operations, House of Representatives, One Hundredth Congress, second session, April 28, 1988. Washington: U.S. G.P.O., 1989.
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Ganina, Vera, Lyudmila Borisova, Viktoriya Morozova, Irina Smirnova, and Elena Yurova. Production control of dairy products. ru: INFRA-M Academic Publishing LLC., 2022. http://dx.doi.org/10.12737/1865668.
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The textbook discusses the basics of production control, which is carried out at the enterprises of the dairy industry. The requirements of regulatory documents for quality indicators of various groups of dairy products are systematically stated, the procedure and methods of input control of raw materials, as well as control during the technological process and finished products are indicated.
For a better perception of the material, standard schemes are given with the allocation of the main points of technical control of physico-chemical and microbiological indicators in the process of dairy production technology.
It is intended for university students studying in the field of training "Animal food products", as well as for employees of dairy enterprises whose activities are related to quality control in production laboratories.
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Fred, Kuchler, and United States. Dept. of Agriculture. Economic Research Service, eds. Chemical inputs and food safety. [Washington, D.C.?]: U.S. Dept. of Agriculture, Economic Research Service, 1993.
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Lippmann, Morton, and Richard B. Schlesinger. Characterization of Contaminants and Environments. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780190688622.003.0002.
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This chapter describes the extensive scientific terminology needed to describe the various classes of chemical contaminants as they occur in environmental media (air, water, soil, etc.) and the structural aspects and dynamic mass and energy transfers within and among the atmosphere, hydrosphere, lithosphere, and biosphere. It also introduces: the characteristics of occupational environments; health effects attributable to occupational and environmental exposures; dose response relationships in populations; and how they are affected by anthropogenic (human activity caused) inputs and disruptions.
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Bromley, Lesley. The physiology of acute pain. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780199234721.003.0001.
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Acute pain as a result of tissue damage is self-limiting. Impulses are generated in primary sensory nerves by chemical mediators released from the damaged tissues. The spinal cord receives these impulses in the dorsal horn. At the level of the spinal cord, the impulses can be amplified or reduced in amplitude by descending inputs. At the level of the spinal cord, the representation of the painful area and the sensitivity of other, surrounding areas can be modified. At the level of the brainstem and thalamus, further modification can take place. The final perception of the pain can be modified by other central phenomena such as anxiety and fear. New imaging techniques have allowed a greater understanding of cortical representation of pain. The role of the glia in maintaining painful states is evolving.
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Martin, Colin. Wreck-Site Formation Processes. Edited by Ben Ford, Donny L. Hamilton, and Alexis Catsambis. Oxford University Press, 2012. http://dx.doi.org/10.1093/oxfordhb/9780199336005.013.0002.
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The environmental settings within which shipwrecks occur are matters of chance rather than of choice. It is primarily the wreck and not its physical context that is of consequence to nautical archaeologists. No two wreck-site formations are the same, since the complex and interacting variables that constitute the environmental setting, the nature of the ship, and the circumstances of its loss combine to create a set of attributes unique to each site. The dynamic phase, which begins with the event of shipwreck, is characterized by the wreck's status as an environmental anomaly. It is unstable, lacks integration with its surroundings, and is prone to further disintegration and dispersal by external influences. The chemical and physical properties of water cause reactions with the metals. Understanding these natural processes in the context of the distinctively anthropogenic inputs, this article characterizes archaeology as an essential prerequisite to the interpretation of any shipwreck.
Book chapters on the topic "Chemical inputs"
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Srivastava, Deepti, Rashmi Maurya, Nadeem Khan, Md Abu Nayyer, Alka Mishra, Faria Fatima, Salman Ahmad, Saba Siddiqui, and Mohd Haris Siddiqui. "General Introduction of Bio-Inputs Versus Chemical Inputs in Agriculture and Ill Effects." In Biofertilizers and Biopesticides in Sustainable Agriculture, 1–22. Includes bibliographical references and index.: Apple Academic Press, 2019. http://dx.doi.org/10.1201/9780429059384-1.
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Andres, L. A., and S. L. Clement. "Opportunities for Reducing Chemical Inputs for Weed Control." In Organic Farming, 129–40. Madison, WI, USA: American Society of Agronomy, Crop Science Society of America, Soil Science Society of America, 2015. http://dx.doi.org/10.2134/asaspecpub46.c10.
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Delucchi, V. L. "Opportunities for Reducing Chemical Inputs for Insect Control in Farming Systems." In Organic Farming, 141–49. Madison, WI, USA: American Society of Agronomy, Crop Science Society of America, Soil Science Society of America, 2015. http://dx.doi.org/10.2134/asaspecpub46.c11.
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Lacerda, Luiz D., and Wim Salomons. "Perspectives on the Temporal Development of Mercury Inputs into the Environment." In Mercury from Gold and Silver Mining: A Chemical Time Bomb?, 111–20. Berlin, Heidelberg: Springer Berlin Heidelberg, 1998. http://dx.doi.org/10.1007/978-3-642-58793-1_7.
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King, C., J. McEniry, M. Richardson, and P. O’Kiely. "The Chemical Composition of a Range of Forage Grasses Grown Under Two Nitrogen Fertiliser Inputs and Harvested at Different Stages of Maturity." In Breeding strategies for sustainable forage and turf grass improvement, 365–70. Dordrecht: Springer Netherlands, 2012. http://dx.doi.org/10.1007/978-94-007-4555-1_50.
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Ali, Jauhar, Madonna Dela Paz, and Christian John Robiso. "Advances in Two-Line Heterosis Breeding in Rice via the Temperature-Sensitive Genetic Male Sterility System." In Rice Improvement, 99–145. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-66530-2_4.
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AbstractHybrid rice technology is a viable strategy to increase rice production and productivity, especially in countries with limited cultivable land for agriculture and irrigation water, along with costlier chemical inputs. The three-line hybrid rice technology adoption rate is slowing down because of restricted heterosis per se, the availability of better combining ability in cytoplasmic male sterile lines, lower hybrid seed reproducibility, and limited market acceptability of hybrids. Two-line heterosis breeding could overcome these shortcomings. However, the wide-scale adoption and use of two-line hybrid rice technology are possible through systematic research and breeding efforts to develop temperature-sensitive genetic male sterile (TGMS) lines with low (<24 °C) critical sterility temperature point, which is discussed in this chapter. Research on the genetics, breeding, grain quality, and resistance to insect pests and diseases for TGMS line development and physiological characterization is also discussed. In addition, the identification and validation of natural sites for TGMS self-seed multiplication and hybrid rice seed production through GIS mapping and climatic data analytical tools are also tackled. The development of high-yielding two-line rice hybrids and improvement in hybrid rice seed reproducibility could help in their wide-scale adoption.
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Jochum, Clemens, Christa Ditschke, and Jean-Pierre Lentz. "Universal Input Program for Chemical Structures." In ACS Symposium Series, 88–101. Washington, DC: American Chemical Society, 1987. http://dx.doi.org/10.1021/bk-1987-0341.ch009.
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Sakkhamduang, Jeeranuch, Mari Arimitsu, and Machito Mihara. "Multi-stakeholder Approach to Conserving Agricultural Biodiversity and Enhancing Food Security and Community Health During the COVID-19 Pandemic in Kampong Cham, Cambodia." In Biodiversity-Health-Sustainability Nexus in Socio-Ecological Production Landscapes and Seascapes (SEPLS), 227–45. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-16-9893-4_11.
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AbstractAgricultural biodiversity plays a vital role in enhancing food security and human health. Sustainable agriculture practices that conserve soil and water can result in good environmental and human health. In view of this, a project on capacity-building for sustainable agricultural practices targeting extension officers was implemented between September 2017 and February 2021 in Kampong Cham Province, Cambodia, by the Institute of Environmental Rehabilitation and Conservation (ERECON), Japan. The project involved government agencies, educational institutes, NGOs, and farmers, and employed a multi-stakeholder approach to promote sustainable farming practices among local farmers and enable conditions for the sale of agricultural products with low chemical inputs, especially in a province where agrochemical application is prevalent. A questionnaire survey, key informant interviews, focus group discussions, and observations from farmers were used for programme monitoring. Farmers reported that soil quality was improved after applying compost, and more beneficial insects were found after integrated pest management techniques were applied. The amount of agrochemicals applied to farmlands decreased compared to usage before the project start, implying that the project was successful in promoting sustainable agriculture in the province. During the COVID-19 pandemic, communities in the project areas are struggling to cope with food and health insecurity. The intervention has helped communities become more resilient during this hard time. After 3 years, many of the approximate 1500 farmers involved in the project are applying organic fertilisers and enhancing agricultural biodiversity in their farmlands. This case is a grassroots-level activity, but the concept of multi-stakeholder activities for agricultural biodiversity conservation can be replicated in other areas of Cambodia for achieving the sustainable development goals.
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Blower, Paul E., Steve W. Chapman, Robert C. Dana, Howard J. Erisman, and Dale E. Hartzler. "Poster Session: Machine Generation of Multi-Step Reactions in a Document from Single-Step Input Reactions." In Chemical Structures, 399–407. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-73975-0_41.
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Wisniewski, Janusz L. "AUTONOM — A Chemist’s Dream: System for (Micro)Computer Generation of IUPAC-Compatible Names from Structural Input." In Chemical Structures 2, 55–63. Berlin, Heidelberg: Springer Berlin Heidelberg, 1993. http://dx.doi.org/10.1007/978-3-642-78027-1_6.
Full textConference papers on the topic "Chemical inputs"
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Ilchmann, A., M. Thuto, and S. Townley. "λ-Tracking for exothermic chemical reactions with saturating inputs." In 2001 European Control Conference (ECC). IEEE, 2001. http://dx.doi.org/10.23919/ecc.2001.7076204.
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Steward, Robert L., Chao-Min Cheng, and Philip R. LeDuc. "Probing Dynamic Responses of the Extracellular Matrix to Coupled Mechanical and Chemical Inputs." In ASME 2010 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2010. http://dx.doi.org/10.1115/sbc2010-19206.
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The extracellular matrix (ECM) is an important cellular component that provides structural support for cells that form the various connective tissues in the body and has been linked to various important cellular processes. One major, ubiquitously expressed ECM protein, fibronectin (FN) has been well documented to play an important role in the ECM, but most studies have investigated FN and its assembly and structural organization mainly through chemical stimulation. The ECM though likely experiences multiple modes of stimulation such as mechanical and chemical inputs. Since cells and the ECM may experience mechanical and chemical stimulation, we examined how NIH 3T3 fibroblasts altered their ECM in response to applied mechanical and chemical stimulation. Mechanical stimulation revealed an increase in FN matrix formation and secretion as reflected by immunofluorescence as well as FN localization around the cell periphery. Coupling of mechanical stimulation with chemical stimulation via inhibition of Rho activity revealed the same behavior as cells exposed purely to mechanical stimulation. This study is among the first to show the effect of coupled modes of stimulation on the ECM and show a purely mechanics-induced stimulation of ECM formation. These results have implications in a variety of fields including mechanotransduction, biophysics and bioengineering.
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Shao, Guodong, Peter Denno, Albert Jones, and Yan Lu. "Implementing the ISO 15746 Standard for Chemical Process Optimization." In ASME 2016 11th International Manufacturing Science and Engineering Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/msec2016-8635.
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This paper proposes an approach to integrating advanced process control solutions with optimization (APC-O) solutions, within any factory, to enable more efficient production processes. Currently, vendors who provide the software applications that implement control solutions are isolated and relatively independent. Each such solution is designed to implement a specific task such as control, simulation, and optimization — and only that task. It is not uncommon for vendors to use different mathematical formalisms and modeling tools that produce different data representations and formats. Moreover, instead of being modeled uniformly only once, the same knowledge is often modeled multiple times — each time using a different, specialized abstraction. As a result, it is extremely difficult to integrate optimization with advanced process control. We believe that a recent standard, International Organization for Standardization (ISO) 15746, describes a data model that can facilitate that integration. In this paper, we demonstrate a novel method of integrating advanced process control using ISO 15746 with numerical optimization. The demonstration is based on a chemical-process-optimization problem, which resides at level 2 of the International Society of Automation (ISA) 95 architecture. The inputs to that optimization problem, which are captured in the ISO 15746 data model, come in two forms: goals from level 3 and feedback from level 1. We map these inputs, using this data model, to a population of a meta-model of the optimization problem for a chemical process. Serialization of the metamodel population provides input to a numerical optimization code of the optimization problem. The results of this integrated process, which is automated, provide the solution to the originally selected, level 2 optimization problem.
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Meng, Jiandong, and Yogesh Jaluria. "Transient Behavior of the Gallium Nitride Chemical Vapor Deposition Process." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-63236.
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The transient behavior of the Gallium Nitride deposition process in a CVD reactor is numerically investigated. A two-dimensional impinging reactor is considered to examine the time-dependent transport in the MOCVD process, including the steady-state deposition process, and the system start-up and shut-down. The study involves the consideration of complicated transport phenomena, including fluid flow, heat and mass transfer, and chemical reactions between the reactants and the intermediate species. The temperature field and the deposition rate are studied as functions of time, as well as the precursor mass fraction at certain times. The results obtained provide an in-depth understanding about the entire MOCVD process, and the possibility to control the system operating time and the consumption of input power and precursors, which are generally quite expensive. It also provided inputs on the effects of changing operating conditions and the duration of starting and shut down effects.
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Zhang, Xiaosong, and Hongguang Jin. "A Novel Chemical-Looping Hydrogen Generation System With Multi-Input Fossil Fuels." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-94655.
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This paper proposes a multi-input chemical looping hydrogen generation system (MCLH), which generates hydrogen, through the use of natural gas and coal. In this system, a new type of oven, burning coal instead of natural gas as heating resource for hydrogen production reaction, is adopted. Coal can be converted to hydrogen indirectly without gasification. Benefits from the chemical looping process, the CO2 can be captured without energy penalty. With the same inputs of fuel, the new system can product about 16% more hydrogen than that of individual systems. As a result, the energy consumption of the hydrogen production is about 165J/mol-H2. Based on the exergy analyses, it is disclosed that the integration of synthetic utilization of natural gas and coal plays a significant role in reducing the exergy destruction of the MCLH system. The promising results obtained may lead to a clean coal technology that will utilize natural gas and coal more efficiently and economically.
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Schor, Alisha R., and H. Harry Asada. "Approximating a MIMO, 1D Diffusion System to a Low Order, State-Space Form in Order to Facilitate Controller Design." In ASME 2010 Dynamic Systems and Control Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/dscc2010-4071.
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Chemical distribution is an important factor in many biological systems, driving the phenomenon known as chemotaxis. In order to properly study the effects of various chemical inputs to an in vitro biological assay, it is necessary to have strict control over the spatial distribution of these chemicals. This distribution is typically governed by diffusion, which by nature is a distributed parameter system (DPS), dependent on both space and time. Much study and literature within the controls community has been devoted to DPS, whose dynamics are marked by partial differential equations or delays. They span an infinite-dimensional state-space, and the mathematical complexity associated with this leads to the development of controllers that are often highly abstract in nature. In this paper, we present a method of approximating these systems and expressing them in a manner that makes a DPS amenable to control using a very low order model. In particular, we express the PDE for one-dimensional chemical diffusion as a two-input, two-output state-space system and show that standard controllers can manipulate the outputs of interest, using pole placement and integral control via an augmented state model.
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Giraldo, Mario, and Hector Botero. "Design of unknown inputs observer for a chemical process: Analysis of existence and observability based on phenomenological model." In 2011 IEEE IX Latin American Robotics Symposium and IEEE Colombian Conference on Automatic Control (LARC). IEEE, 2011. http://dx.doi.org/10.1109/larc.2011.6086823.
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Abuhimd, Hatem, Abe Zeid, Yung Joon Jung, and Sagar Kamarthi. "Process Design for the Controlability of Chemical Vapor Deposition Grown Vertically Aligned Single Walled Carbon Nanotubes." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-62909.
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Carbon nanotubes (CNTs) have received much attention from both the scientific and industrial communities due to their structural properties and unique morphology. There has also been growing interest in vertically aligned single walled carbon nanotubes (VA-SWNTs) because of their suitability for building devices such as hydrogen storage and super capacitors. Various methods including chemical vapor deposition (CVD) have been developed for growing VA-SWNTs. Among them is alcohol catalytic CVD which is well known for its economic viability, comprehensive substrates selectivity and good yield of VA-SWNTs. In order to fully understand the growth mechanism of those CNTs, an examination of the role of inputs like hydrocarbon flow rate, reaction time, chamber temperature, and pressure is essential. This work studies the controllability of VA-SWNTs growth by a hybrid process model of an experimental design and an artificial neural network (ANN). Process analysis shows that CVD pressure and temperature are the most significant input factors. In addition, interactions and response surface plots confirm these results and add that higher temperature and pressure will yield VA-SWNTs with high probability.
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Ozalp, Nesrin. "Utilization of Heat, Power and Recovered Waste Heat for Industrial Processes in the US Chemical Industry." In ASME 2008 2nd International Conference on Energy Sustainability collocated with the Heat Transfer, Fluids Engineering, and 3rd Energy Nanotechnology Conferences. ASMEDC, 2008. http://dx.doi.org/10.1115/es2008-54120.
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This paper presents energy end-use model of the U.S. Chemical Industry. The model allocates combustible fuel and renewable energy inputs among generic end-uses including intermediate conversions through onsite power and steam generation. Results of this model provide the basis to scale energy process-step models. Two federal databases used to construct energy end-use models are Manufacturing Energy Consumption Survey of the U.S. Energy Information Administration, and the Energy Information Administration’s “EIA-860B: Annual Electric Generator Report”. These databases provide information on energy consumption for each end-use, electricity generation, and recovered waste heat at the prime mover level of detail for each industry on a national scale. Results of the model show that the majority of the fuel input is used directly for the end-uses. Although the rest of the fuel is used to generate steam and power, most of this energy contributes to the end-uses as steam. Therefore, the purpose of fuel consumption at non-utility plants is to run their end-uses. During the course of this study, the most recent U.S. federal energy database available was for the year 1998. Currently, the most recent available U.S. federal energy database is given for the year 2002 based on the data collected from 15,500 establishments.
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Huang, Jiayi /., Dachun /. Feng, Ming /. Pan, and Qiubo /. Xie. "Supervision and Big Data Application of Agricultural Chemical Inputs Used by Small-scale Farmers in the Hilly and Mountainous Areas." In 2019 Boston, Massachusetts July 7- July 10, 2019. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2019. http://dx.doi.org/10.13031/aim.201900705.
Full textReports on the topic "Chemical inputs"
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Berkowitz, Jacob, Christine VanZomeren, and Nicole Fresard. Rapid formation of iron sulfides alters soil morphology and chemistry following simulated marsh restoration. Engineer Research and Development Center (U.S.), September 2021. http://dx.doi.org/10.21079/11681/42155.
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Many marshes show signs of degradation due to fragmentation, lack of sediment inputs, and erosion which may be exacerbated by sea level rise and increasing storm frequency/intensity. As a result, resource managers seek to restore marshes via introduction of sediment to increase elevation and stabilize the marsh platform. Recent field observations suggest the rapid formation of iron sulfide (FeS) materials following restoration in several marshes. To investigate, a laboratory microcosm study evaluated the formation of FeS following simulated restoration activities under continually inundated, simulated drought, and simulated tidal conditions. Results indicate that FeS horizon development initiated within 16 days, expanding to encompass > 30% of the soil profile after 120 days under continuously inundated and simulated tidal conditions. Continuously inundated conditions supported higher FeS content compared to other treatments. Dissolved and total Fe and S measurements suggest the movement and diffusion of chemical constituents from native marsh soil upwards into the overlying sediments, driving FeS precipitation. The study highlights the need to consider biogeochemical factors resulting in FeS formation during salt marsh restoration activities. Additional field research is required to link laboratory studies, which may represent a worst-case scenario, with in-situ conditions.
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Pesis, Edna, Elizabeth J. Mitcham, Susan E. Ebeler, and Amnon Lers. Application of Pre-storage Short Anaerobiosis to Alleviate Superficial Scald and Bitter Pit in Granny Smith Apples. United States Department of Agriculture, January 2013. http://dx.doi.org/10.32747/2013.7593394.bard.
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There is increased demand for high quality fruit produced and marketed with reduced chemical inputs to minimize toxic effects on human health and the environment. Granny Smith (GS) apple quality is reduced by two major physiological disorders, superficial scald and bitter pit (BP). These disorders cause great loss to apple growers worldwide. Superficial scald is commonly controlled by chemical treatments, mainly the antioxidant diphenylamine (DPA) and/or the ethylene action inhibitor, 1-methylcyclopropene (1–MCP). Both chemicals are ineffective in controlling bitter pit incidence. We proposed to investigate the beneficial use of non-chemical, abiotic stress with low O2 (LO2) applied for 10d at 20°C on GS apple fruit. During the project we expanded the treatment to more apple cultivars, Golden Delicious (GD) and Starking Delicious (SD) and another pome fruit, the pear. Apple and pear have similar physiological disorders that develop during cold storage and we examined if the LO2 treatment would also be effective on pear. Application of 0.5% LO2 atmosphere for 10d at 20°C or 500ppb 1-MCP at 20°C prior to cold storage at 0°C, was effective in reducing superficial scald in GS apple. Moreover, LO2 pretreatment was also effective in reducing bitter pit (BP) development in California GS and Israeli GD and SD apples The BP symptoms in GS from California were much more prominent, so the effect of LO2 was more dramatic than the effect on the Israeli cvs. GD and SD, nevertheless the LO2 treatment showed the same trend in all cultivars in reducing BP. The LO2 and 1-MCP -treated fruit exhibited lower levels of ethylene, - farnesene and its oxidation product, 6-methyl-5-hepten-2-one (MHO), as determined by SPME/GC-MS analysis. In addition, LO2 pretreatment applied to California Bartlett or Israeli Spadona pears was effective in reducing superficial scald, senescent scald and internal breakdown after 4 m of cold storage at 0°C. For GS apple, low-temperature storage resulted in oxidative stress and chilling injury, caused by increased production of superoxide anions which in turn led to the generation of other dangerous reactive oxygen species (ROS). Using confocal laser-scanning microscopy and H2O2 measurements of apple peel, we observed ROS accumulation in control fruit, while negligible amounts were found in LO2 and 1-MCP treated fruit. Gene-expression levels of ROS-scavenging enzymes were induced by the various pretreatments: catalase was induced by LO2 treatment, whereas Mn superoxide dismutase was induced by 1-MCP treatment. We assume that LO2 and 1-MCP pretreated fruit remained healthier due to reduced production of ethylene and reactive oxygen substances, such as MHO, during cold storage. The LO2-treated apple exhibited greener peel and firmer fruit after 6 m of cold storage, and the fruit had high crispiness leading to high taste preference. In both pear cultivars, the LO2 treatment led to a reduction in internal breakdown and browning around the seed cavity. We tested the LO2 pre-storage treatment on a semi-commercial scale that would be applicable to a small organic grower by sealing the fruit within the plastic field bins. The treatment was most effective with a continuous flow of nitrogen through the bins; however, a single 6 hour flush of nitrogen was also fairly effective. In addition, we determined that it was very important to have the oxygen levels below 0.5% for approximately 10 days to achieve good scald control, not counting the time required to reduce the oxygen concentration. Our LO2 technology has been proven in this project to be effective in reducing several physiological disorders developed in pome fruit during cold storage. We hope that our non-chemical treatment which is friendly to the environment will be used in the near future for the organic apple and pear industry. The next step should be an analysis of the cost-benefits and commercial feasibility.
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Perl, Avichai, Bruce I. Reisch, and Ofra Lotan. Transgenic Endochitinase Producing Grapevine for the Improvement of Resistance to Powdery Mildew (Uncinula necator). United States Department of Agriculture, January 1994. http://dx.doi.org/10.32747/1994.7568766.bard.
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The original objectives are listed below: 1. Design vectors for constitutive expression of endochitinase from Trichoderma harzianum strain P1. Design vectors with signal peptides to target gene expression. 2. Extend transformation/regeneration technology to other cultivars of importance in the U.S. and Israel. 3. Transform cultivars with the endochitinase constructs developed as part of objective 1. A. Characterize foliar powdery mildew resistance in transgenic plants. Background of the topic Conventional breeding of grapevines is a slow and imprecise process. The long generation cycle, large space requirements and poor understanding of grapevine genetics prevent rapid progress. There remains great need to improve existing important cultivars without the loss of identity that follows from hybridization. Powdery mildew (Uncinula necator) is the most important fungal pathogen of grapevines, causing economic losses around the world. Genetic control of powdery mildew would reduce the requirement for chemical or cultural control of the disease. Yet, since the trait is under polygenic control, it is difficult to manipulate through hybridization and breeding. Also, because grapevines are heterozygous and vegetatively propagated cultivar identity is lost in the breeding process. Therefore, there is great need for techniques to produce transgenic versions of established cultivars with heterologous genes conferring disease resistance. Such a gene is now available for control of powdery mildew of grapevines. The protein coded by the Endochitinase gene, derived from Trichoderma harzianum, is very effective in suppressing U. necator growth. The goal of this proposal is to develop transgenic grapevines with this antifungal gene, and to test the effect of this gene on resistance to powdery mildew. Conclusions, achievements and implications Gene transfer technology for grape was developed using commercial cultivars for both wine and table grapes. It paved the way for a new tool in grapevine genetic studies enabling the alteration of specific important traits while maintaining the essential features of existing elite cultivars. Regeneration and transformation technologies were developed and are currently at an advanced stage for USA wine and Israeli seedless cultivars, representing the cutting edge of grape genetic engineering studies worldwide. Transgenic plants produced are tested for powdery mildew resistance in greenhouse and field experiments at both locations. It is our ultimate goal to develop transgenic grapes which will be more efficient and economical for growers to produce, while also providing consumers with familiar products grown with reduced chemical inputs.
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Савосько, Василь Миколайович, Юлія Бєлик, and Юрій Васильович Лихолат. Ecological and Geological Determination of the Initial Pedogenesis on Devastated Lands in the Kryvyi Rih Iron Mining & Metallurgical District (Ukraine). Journ. Geol. Geograph. Geoecology, 2019. http://dx.doi.org/10.31812/123456789/3643.
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In our time, a very urgent problem is the cessation of negative impacts on the environment and the return to the practical use of the territories of devastated lands. In this regard, it is important to find out the basic laws of primary soil formation in the area of these man-made neoplasms. The initial soil formation conditions were analyzed on 19 experimental sites which represent the main varieties of devastated land in the Kryvyi Rih Iron Mining and Metallurgical District (Central Ukraine): (i) waste rock dumps of old iron mines (old name “Forges”), (ii) tailing storage facility of underground iron mines, (iii) waste rock dumps of the Iron Ore Mining and Dressing Plant, (iv) waste rock dumps of the Granite Quarry Plant. It was established that on the devastated lands in Kryvyi Rih District, the initial soil formation occurs in very difficult conditions. Therefore, over 25- 100 years only very primitive soils were formed. The following features are inherent to them: (1) primitive soil profile (thickness 10-100 mm), (2) low levels of soil organic substance content (9.5-11.5 %), (3) alkaline indicators of the soil solution (pHH2O – 8.08-8.92, pHKCl – 7.42-8.23), (4) low levels of cation exchange capacity (6.34-8.47 mMol /100 g). By results of correlation calculations, among the factors of soil formation time (duration of soil formation) and input of plant ash elements’ fall are characterized by the maximum number of statistically significant correlation coefficients and their numerical values. In terms of chemical composition of the technosol, the values of organic matter content and exchangeable acidity (pHKCl) were the most predictable soil formation factors. Generally physical / chemical characteristics of geological rocks (as parent material) and time were the two most important factors in determining the initial pedogenesis on devastated lands in the Kryvyi Rih Iron Mining & Metallurgical District (Ukraine).
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Banin, Amos, Joseph Stucki, and Joel Kostka. Redox Processes in Soils Irrigated with Reclaimed Sewage Effluents: Field Cycles and Basic Mechanism. United States Department of Agriculture, July 2004. http://dx.doi.org/10.32747/2004.7695870.bard.
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The overall objectives of the project were: (a) To measure and study in situ the effect of irrigation with reclaimed sewage effluents on redox processes and related chemical dynamics in soil profiles of agricultural fields. (b) To study under controlled conditions the kinetics and equilibrium states of selected processes that affect redox conditions in field soils or that are effected by them. Specifically, these include the effects on heavy metals sorption and desorption, and the effect on pesticide degradation. On the basis of the initial results from the field study, increased effort was devoted to clarifying and quantifying the effects of plants and water regime on the soil's redox potential while the study of heavy metals sorption was limited. The use of reclaimed sewage effluents as agricultural irrigation water is increasing at a significant rate. The relatively high levels of suspended and, especially, dissolved organic matter and nitrogen in effluents may affect the redox regime in field soils irrigated with them. In turn, the changes in redox regime may affect, among other parameters, the organic matter and nitrogen dynamics of the root zone and trace organic decomposition processes. Detailed data of the redox potential regime in field plots is lacking, and the detailed mechanisms of its control are obscure and not quantified. The study established the feasibility of long-term, non-disturbing monitoring of redox potential regime in field soils. This may enable to manage soil redox under conditions of continued inputs of wastewater. The importance of controlling the degree of wastewater treatment, particularly of adding ultrafiltration steps and/or tertiary treatment, may be assessed based on these and similar results. Low redox potential was measured in a field site (Site A, KibutzGivat Brenner), that has been irrigated with effluents for 30 years and was used for 15 years for continuous commercial sod production. A permanently reduced horizon (Time weighted averaged pe= 0.33±3.0) was found in this site at the 15 cm depth throughout the measurement period of 10 months. A drastic cultivation intervention, involving prolonged drying and deep plowing operations may be required to reclaim such soils. Site B, characterized by a loamy texture, irrigated with tap water for about 20 years was oxidized (Time weighted average pe=8.1±1.0) throughout the measurement period. Iron in the solid phases of the Givat Brenner soils is chemically-reduced by irrigation. Reduced Fe in these soils causes a change in reactivity toward the pesticide oxamyl, which has been determined to be both cytotoxic and genotoxic to mammalian cells. Reaction of oxamyl with reduced-Fe clay minerals dramatically decreases its cytotoxicity and genotoxicity to mammalian cells. Some other pesticides are affected in the same manner, whereas others are affected in the opposite direction (become more cyto- and genotoxic). Iron-reducing bacteria (FeRB) are abundant in the Givat Brenner soils. FeRB are capable of coupling the oxidation of small molecular weight carbon compounds (fermentation products) to the respiration of iron under anoxic conditions, such as those that occur under flooded soil conditions. FeRB from these soils utilize a variety of Fe forms, including Fe-containing clay minerals, as the sole electron acceptor. Daily cycles of the soil redox potential were discovered and documented in controlled-conditions lysimeter experiments. In the oxic range (pe=12-8) soil redox potential cycling is attributed to the effect of the daily temperature cycle on the equilibrium constant of the oxygenation reaction of H⁺ to form H₂O, and is observed under both effluent and freshwater irrigation. The presence of plants affects considerably the redox potential regime of soils. Redox potential cycling coupled to the irrigation cycles is observed when the soil becomes anoxic and the redox potential is controlled by the Fe(III)/Fe(II) redox couple. This is particularly seen when plants are grown. Re-oxidation of the soil after soil drying at the end of an irrigation cycle is affected to some degree by the water quality. Surprisingly, the results suggest that under certain conditions recovery is less pronounced in the freshwater irrigated soils.
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Morkun, Volodymyr, Natalia Morkun, Andrii Pikilnyak, Serhii Semerikov, Oleksandra Serdiuk, and Irina Gaponenko. The Cyber-Physical System for Increasing the Efficiency of the Iron Ore Desliming Process. CEUR Workshop Proceedings, April 2021. http://dx.doi.org/10.31812/123456789/4373.
Full textAbstract:
It is proposed to carry out the spatial effect of high-energy ultrasound dynamic effects with controlled characteristics on the solid phase particles of the ore pulp in the deslimer input product to increase the efficiency of thickening and desliming processes of iron ore beneficiation products. The above allows predicting the characteristics of particle gravitational sedimentation based on an assessment of the spatial dynamics of pulp solid- phase particles under the controlled action of high-energy ultrasound and fuzzy logical inference. The object of study is the assessment of the characteristics and the process of control the operations of thickening and deslaming of iron ore beneficiation products in the conditions of the technological line of the ore beneficiation plant. The subject of study is a cyber-physical system based on the use of high-energy ultrasound radiation pressure effects on iron-containing beneficiation products in the technological processes of thickening and desliming. The working hypothesis of the project is that there is a relationship between the physical-mechanical and chemical-mineralogical characteristics of the iron ore pulp solid- phase particles and their behavior in technological flows under the influence of controlled ultrasonic radiation, based on which the imitation modeling of the gravitational sedimentation process of the iron ore pulp solid-phase particles can be performed directly in the technological process. Also, the optimal control actions concerning the processes of thickening and desliming can be determined.
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de Caritat, Patrice, Brent McInnes, and Stephen Rowins. Towards a heavy mineral map of the Australian continent: a feasibility study. Geoscience Australia, 2020. http://dx.doi.org/10.11636/record.2020.031.
Full textAbstract:
Heavy minerals (HMs) are minerals with a specific gravity greater than 2.9 g/cm3. They are commonly highly resistant to physical and chemical weathering, and therefore persist in sediments as lasting indicators of the (former) presence of the rocks they formed in. The presence/absence of certain HMs, their associations with other HMs, their concentration levels, and the geochemical patterns they form in maps or 3D models can be indicative of geological processes that contributed to their formation. Furthermore trace element and isotopic analyses of HMs have been used to vector to mineralisation or constrain timing of geological processes. The positive role of HMs in mineral exploration is well established in other countries, but comparatively little understood in Australia. Here we present the results of a pilot project that was designed to establish, test and assess a workflow to produce a HM map (or atlas of maps) and dataset for Australia. This would represent a critical step in the ability to detect anomalous HM patterns as it would establish the background HM characteristics (i.e., unrelated to mineralisation). Further the extremely rich dataset produced would be a valuable input into any future machine learning/big data-based prospectivity analysis. The pilot project consisted in selecting ten sites from the National Geochemical Survey of Australia (NGSA) and separating and analysing the HM contents from the 75-430 µm grain-size fraction of the top (0-10 cm depth) sediment samples. A workflow was established and tested based on the density separation of the HM-rich phase by combining a shake table and the use of dense liquids. The automated mineralogy quantification was performed on a TESCAN® Integrated Mineral Analyser (TIMA) that identified and mapped thousands of grains in a matter of minutes for each sample. The results indicated that: (1) the NGSA samples are appropriate for HM analysis; (2) over 40 HMs were effectively identified and quantified using TIMA automated quantitative mineralogy; (3) the resultant HMs’ mineralogy is consistent with the samples’ bulk geochemistry and regional geological setting; and (4) the HM makeup of the NGSA samples varied across the country, as shown by the mineral mounts and preliminary maps. Based on these observations, HM mapping of the continent using NGSA samples will likely result in coherent and interpretable geological patterns relating to bedrock lithology, metamorphic grade, degree of alteration and mineralisation. It could assist in geological investigations especially where outcrop is minimal, challenging to correctly attribute due to extensive weathering, or simply difficult to access. It is believed that a continental-scale HM atlas for Australia could assist in derisking mineral exploration and lead to investment, e.g., via tenement uptake, exploration, discovery and ultimately exploitation. As some HMs are hosts for technology critical elements such as rare earth elements, their systematic and internally consistent quantification and mapping could lead to resource discovery essential for a more sustainable, lower-carbon economy.
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Shenker, Moshe, Paul R. Bloom, Abraham Shaviv, Adina Paytan, Barbara J. Cade-Menun, Yona Chen, and Jorge Tarchitzky. Fate of Phosphorus Originated from Treated Wastewater and Biosolids in Soils: Speciation, Transport, and Accumulation. United States Department of Agriculture, June 2011. http://dx.doi.org/10.32747/2011.7697103.bard.
Full textAbstract:
Beneficial use of reclaimed wastewater (RW) and biosolids (BS) in soils is accompanied by large input of sewage-originated P. Prolonged application may result in P accumulation up to levelsBeneficial use of reclaimed wastewater (RW) and biosolids (BS) in soils is accompanied by large input of sewage-originated P. Prolonged application may result in P accumulation up to levels that impair plant nutrition, increase P loss, and promote eutrophication in downstream waters. This study aims to shed light on the RW- and BS-P forms in soils and to follow the processes that determine P reactivity, solubility, availability, and loss in RW and BS treated soils. The Technion group used sequential P extraction combined with measuring stable oxygen isotopic composition in phosphate (δ18OP) and with 31P-NMR studies to probe P speciation and transformations in soils irrigated with RW or fresh water (FW). The application of the δ18OP method to probe inorganic P (Pi) speciation and transformations in soils was developed through collaboration between the Technion and the UCSC groups. The method was used to trace Pi in water-, NaHCO3-, NaOH-, and HCl- P fractions in a calcareous clay soil (Acre, Israel) irrigated with RW or FW. The δ18OP signature changes during a month of incubation indicated biogeochemical processes. The water soluble Pi (WSPi) was affected by enzymatic activity yielding isotopic equilibrium with the water molecules in the soil solution. Further it interacted rapidly with the NaHCO3-Pi. The more stable Pi pools also exhibited isotopic alterations in the first two weeks after P application, likely related to microbial activity. Isotopic depletion which could result from organic P (PO) mineralization was followed by enrichment which may result from biologic discrimination in the uptake. Similar transformations were observed in both soils although transformations related to biological activity were more pronounced in the soil treated with RW. Specific P compounds were identified by the Technion group, using solution-state 31P-NMR in wastewater and in soil P extracts from Acre soils irrigated by RW and FW. Few identified PO compounds (e.g., D-glucose-6-phosphate) indicated coupled transformations of P and C in the wastewater. The RW soil retained higher P content, mainly in the labile fractions, but lower labile PO, than the FW soil; this and the fact that P species in the various soil extracts of the RW soil appear independent of P species in the RW are attributed to enhanced biological activity and P recycling in the RW soil. Consistent with that, both soils retained very similar P species in the soil pools. The HUJ group tested P stabilization to maximize the environmental safe application rates and the agronomic beneficial use of BS. Sequential P extraction indicated that the most reactive BS-P forms: WSP, membrane-P, and NaHCO3-P, were effectively stabilized by ferrous sulfate (FeSul), calcium oxide (CaO), or aluminum sulfate (alum). After applying the stabilized BS, or fresh BS (FBS), FBS compost (BSC), or P fertilizer (KH2PO4) to an alluvial soil, P availability was probed during 100 days of incubation. A plant-based bioassay indicated that P availability followed the order KH2PO4 >> alum-BS > BSC ≥ FBS > CaO-BS >> FeSul-BS. The WSPi concentration in soil increased following FBS or BSC application, and P mineralization further increased it during incubation. In contrast, the chemically stabilized BS reduced WSPi concentrations relative to the untreated soil. It was concluded that the chemically stabilized BS effectively controlled WSPi in the soil while still supplying P to support plant growth. Using the sequential extraction procedure the persistence of P availability in BS treated soils was shown to be of a long-term nature. 15 years after the last BS application to MN soils that were annually amended for 20 years by heavy rates of BS, about 25% of the added BS-P was found in the labile fractions. The UMN group further probed soil-P speciation in these soils by bulk and micro X-ray absorption near edge structure (XANES). This newly developed method was shown to be a powerful tool for P speciation in soils. In a control soil (no BS added), 54% of the total P was PO and it was mostly identified as phytic acid; 15% was identified as brushite and 26% as strengite. A corn crop BS amended soil included mostly P-Fe-peat complex, variscite and Al-P-peat complex but no Ca-P while in a BS-grass soil octacalcium phosphate was identified and o-phosphorylethanolamine or phytic acid was shown to dominate the PO fraction that impair plant nutrition, increase P loss, and promote eutrophication in downstream waters. This study aims to shed light on the RW- and BS-P forms in soils and to follow the processes that determine P reactivity, solubility, availability, and loss in RW and BS treated soils. The Technion group used sequential P extraction combined with measuring stable oxygen isotopic composition in phosphate (δ18OP) and with 31P-NMR studies to probe P speciation and transformations in soils irrigated with RW or fresh water (FW). The application of the δ18OP method to probe inorganic P (Pi) speciation and transformations in soils was developed through collaboration between the Technion and the UCSC groups. The method was used to trace Pi in water-, NaHCO3-, NaOH-, and HCl- P fractions in a calcareous clay soil (Acre, Israel) irrigated with RW or FW. The δ18OP signature changes during a month of incubation indicated biogeochemical processes. The water soluble Pi (WSPi) was affected by enzymatic activity yielding isotopic equilibrium with the water molecules in the soil solution. Further it interacted rapidly with the NaHCO3-Pi. The more stable Pi pools also exhibited isotopic alterations in the first two weeks after P application, likely related to microbial activity. Isotopic depletion which could result from organic P (PO) mineralization was followed by enrichment which may result from biologic discrimination in the uptake. Similar transformations were observed in both soils although transformations related to biological activity were more pronounced in the soil treated with RW. Specific P compounds were identified by the Technion group, using solution-state 31P-NMR in wastewater and in soil P extracts from Acre soils irrigated by RW and FW. Few identified PO compounds (e.g., D-glucose-6-phosphate) indicated coupled transformations of P and C in the wastewater. The RW soil retained higher P content, mainly in the labile fractions, but lower labile PO, than the FW soil; this and the fact that P species in the various soil extracts of the RW soil appear independent of P species in the RW are attributed to enhanced biological activity and P recycling in the RW soil. Consistent with that, both soils retained very similar P species in the soil pools. The HUJ group tested P stabilization to maximize the environmental safe application rates and the agronomic beneficial use of BS. Sequential P extraction indicated that the most reactive BS-P forms: WSP, membrane-P, and NaHCO3-P, were effectively stabilized by ferrous sulfate (FeSul), calcium oxide (CaO), or aluminum sulfate (alum). After applying the stabilized BS, or fresh BS (FBS), FBS compost (BSC), or P fertilizer (KH2PO4) to an alluvial soil, P availability was probed during 100 days of incubation. A plant-based bioassay indicated that P availability followed the order KH2PO4 >> alum-BS > BSC ≥ FBS > CaO-BS >> FeSul-BS. The WSPi concentration in soil increased following FBS or BSC application, and P mineralization further increased it during incubation. In contrast, the chemically stabilized BS reduced WSPi concentrations relative to the untreated soil. It was concluded that the chemically stabilized BS effectively controlled WSPi in the soil while still supplying P to support plant growth. Using the sequential extraction procedure the persistence of P availability in BS treated soils was shown to be of a long-term nature. 15 years after the last BS application to MN soils that were annually amended for 20 years by heavy rates of BS, about 25% of the added BS-P was found in the labile fractions. The UMN group further probed soil-P speciation in these soils by bulk and micro X-ray absorption near edge structure (XANES). This newly developed method was shown to be a powerful tool for P speciation in soils. In a control soil (no BS added), 54% of the total P was PO and it was mostly identified as phytic acid; 15% was identified as brushite and 26% as strengite. A corn crop BS amended soil included mostly P-Fe-peat complex, variscite and Al-P-peat complex but no Ca-P while in a BS-grass soil octacalcium phosphate was identified and o-phosphorylethanolamine or phytic acid was shown to dominate the PO fraction.