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Статті в журналах з теми "Nitrate use efficiency"
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Wang, Ya-Yun, Yu-Hsuan Cheng, Kuo-En Chen, and Yi-Fang Tsay. "Nitrate Transport, Signaling, and Use Efficiency." Annual Review of Plant Biology 69, no. 1 (April 29, 2018): 85–122. http://dx.doi.org/10.1146/annurev-arplant-042817-040056.
Повний текст джерела
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João, Jair Juarez, José Luiz Vieira, Marcos Henrique Luciano Silveira, Cristiane Silvano Wensing, Paulo Cesar de Jesus, and Endler Marcel Borges. "Valorization of Agro-Industrial By-products: Use of Rice Husk as a Source of Microorganisms to Denitrification of Water." Journal of Agricultural Studies 8, no. 4 (September 1, 2020): 288. http://dx.doi.org/10.5296/jas.v8i4.17624.
Повний текст джерелаАнотація:
Rice husk, which is an agricultural waste, provides a feasible alternative for the growth and propagation of denitrifying microorganisms. Nitrate and nitrite were removed using Immobilized Microorganisms (MOIM) or Microorganisms in Solution (MOSO). Microorganisms present in the rice husk biomass responsible for denitrification were identified as Pseudomonas, and other microorganisms have also been identified, as Oerskovia spp. Enterococcus sp. Bacillus mycoides and Escherichia coli. The influence of pH, temperature, C/N ratio and carbon source on biological denitrification were investigated. MOIM and MOSO consortium had optimal denitrifying performance at 25-30 °C and in pH 7-8. MOSO has average denitrification efficiency larger than MOIM. The MOIM denitrification efficiency was more sensitive to pH changes than the MOSO. Ethanol and sodium acetate were carbon sources for the denitrifying process. The efficiency of nitrate and nitrite removal using MOSO and ethanol or acetate with 1:1, 1:2, 1:3 and 1:4 C/N ratios were equivalents and above 97.00%. The denitrifying process presented was robust and it presented nitrate removal close to 100% during 10 cycles.
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Dorosh, L. S., T. B. Peretyatko, and S. P. Gudz. "The patterns of utilization of sulfate and nitrate ions by bacteria Desulfomicrobium sp. CrR3 and Desulfovibrio desulfuricans Ya-11." Visnyk of Dnipropetrovsk University. Biology, medicine 6, no. 2 (June 23, 2015): 156–60. http://dx.doi.org/10.15421/021528.
Повний текст джерелаАнотація:
The aim of this work was to study the patterns of utilization of sulfate and nitrate ions by bacteria Desulfomicrobium sp. CrR3 and Desulfovibrio desulfuricans Ya-11 under different cultivation conditions. Chromium-resistant sulfate-reducing bacteria Desulfomicrobium sp. CrR3 and D. desulfuricans Ya-11 were used. Bacteria were grown in Posgate C medium at 30°C in 25 ml test tubes under anaerobic conditions. To test the ability of bacteria Desulfomicrobium sp. CrR3 and D. desulfuricans Ya-11 to use various substances and ions as electron acceptors, they were incubated in potassium phosphate buffer (10 mM, pH 7) with sulfate, nitrate and nitrite ions in concentrations of 1, 5 and 10 mM. At various concentrations of sulfate ions (1, 5 and 10 mM), biomass of bacteria Desulfomicrobium sp. CrR3 and D. desulfuricans Ya-11 increased with the increase of concentration of electron acceptor, the maximum biomass was equal to 3.65 and 3.05 g/l at 10 mM of sulfate ions, respectively. With the increase of concentration of nitrate ions to 5 mM the biomass increased by 70% compared to the biomass of bacteria grown in the medium with nitrate ions at the concentration 1 mM. The maximal biomass was determined in the presence of nitrate ions at a concentration of 10 mM – 3.78 and 3.15 g/l for bacteria Desulfomicrobium sp. CrR3 and D. desulfuricans Ya-11, respectively. It is found, as a result of incubation of bacteria Desulfomicrobium sp. CrR3 and D. desulfuricans Ya-11, that by introducing sulfate ions at a concentration of 5 mM bacteria Desulfomicrobium sp. CrR3 used 98%, while D. desulfuricans Ya-11 used only 86%, and under these conditions hydrogen sulfide has been detected in the incubation mixture at the concentration of 0.8–1.0 mM. In the presence of 10 mM of sulfate ions efficiency of electron acceptors utilization was equal to 85–95% for both strains. Bacteria Desulfomicrobium sp. CrR3 intensively used nitrate ions, the efficiency of electron acceptor utilization at 10 mM was equal to 92.8%, while for D. desulfuricans Ya-11 the usage percent amounted to 73% only, and nitrite ions were not observed after three days of incubation. It is established that bacteria Desulfomicrobium sp. CrR3 and D. desulfuricans Ya-11 are capable to use sulfate and nitrate ions as electron acceptors in the process of the disimilatory sulfate and nitratre reduction. As a result of the study of patterns of nitrate utilization by Desulfomicrobium sp. CrR3 and D. desulfuricans Ya-11 it is found that bacteria use nitrate as a nitrogen source for biosynthetic processes, and as electron acceptors. Under these conditions nitrates are reduced to nitrites, and then they are turned to ammonium.
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Soulaiman Bassam Mershed, Bassam Alaji, Soulaiman Bassam Mershed, Bassam Alaji. "Nitrate Removal from Water Using Electrocoagulation with Activated Carbon: إزالة النترات من المياه بالتخثير الكهربائي مع الكربون المنشط". Journal of engineering sciences and information technology 6, № 2 (28 березня 2022): 111–35. http://dx.doi.org/10.26389/ajsrp.c130821.
Повний текст джерелаАнотація:
The present work studies the clarification of drinking water by removing Nitrate and Nitrite using electrocoagulation (EC) and the addition of activated carbon which produced from the almond peel (AP). The efficiency of coupling process studied by using different amounts of adsorbent material to identify the most appropriate dosage, for enhancing drinking water purification, The efficiency of the current density used in the removal of Nitrate and Nitrite was studied, energy consumption of the process was also determined. The coupling between electrocoagulation and the addition of the activated carbon showed that the addition of an appropriate dosage resulted in the enhancement of the removal rate of Nitrate and Nitrite especially at lower current densities, and resulted in a considerable reduction in the needed time compared to the conventional process that does not use activated carbon. The electrocoagulation with the addition of activated carbon achieved efficiency removal of approximately 58.5% for Nitrate and 98.9% for Nitrite. Based on the high removal efficiency, short contact time, and low energy consumption, the electrocoagulation with the addition of activated carbon method could be recommended instead of the conventional process. Furthermore, the results suggest that the productivity of the process is enhanced by adding a very small amount of NaCl as a supporting electrolyte.
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MARISCAL, V., J. REXACH, E. FERNANDEZ, and A. GALVAN. "The plastidic nitrite transporter NAR1;1 improves nitrate use efficiency for growth in Chlamydomonas." Plant, Cell and Environment 27, no. 10 (October 2004): 1321–28. http://dx.doi.org/10.1111/j.1365-3040.2004.01239.x.
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Jiang, Zhongchun, W. Michael Sullivan, and Richard J. Hull. "Nitrate Uptake and Nitrogen Use Efficiency by Kentucky Bluegrass Cultivars." HortScience 35, no. 7 (December 2000): 1350–54. http://dx.doi.org/10.21273/hortsci.35.7.1350.
Повний текст джерелаАнотація:
Efficient utilization of fertilizer-nitrogen (N) by turfgrasses is probably related to N uptake efficiency of roots and metabolic efficiency of absorbed N in roots and shoots. This study evaluated Kentucky bluegrass (Poa pratensis L.) cultivars for potential differences in nitrate uptake rate (NUR), temporal variation in NUR, and the relationship between NUR and N use efficiency (NUE), defined as grams dry matter per gram N. Six cultivars were propagated from tillers of seeded plants, grown in silica sand, mowed weekly, and watered daily with a complete nutrient solution containing 1.0 mm nitrate. A nutrient depletion method from an initial nitrate concentration of 0.5 mm was used to determine NUR of 5-month-old plants. NUR (μmol·h-1 per plant) of the six cultivars ranked as follows: `Blacksburg' > `Conni' > `Dawn' > `Eclipse' = `Barzan' > `Gnome'. When NUR was based on root weight, `Conni' ranked highest; when NUR was based on root length, surface, or volume, `Eclipse' ranked highest. Averaged across cultivars, NUR on the second day was greater than NUR for the first day of nitrate exposure. Temporal variation was greatest in `Blacksburg', while none was noted in `Conni' or `Eclipse'. Cultivar differences in NUE were significant in fibrous roots, rhizomes, and leaf sheaths, but not in leaf blades and thatch. Total nitrate uptake was positively related to total N recovered and total plant dry matter, but NUR based on root weight was negatively correlated with NUE of the whole plant.
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Lea-Cox, J. "Salinity Reduces Water Use and Nitrate-N-use Efficiency of Citrus." Annals of Botany 72, no. 1 (July 1993): 47–54. http://dx.doi.org/10.1006/anbo.1993.1079.
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Xiao, Ji Bo, Hui Xia Jiang, and Shu Yi Chu. "Isolation and Characterization of Denitrifying Bacterium Pseudomonas mendocina aHD7 with Anaerobic Ammonium Oxidization." Applied Mechanics and Materials 178-181 (May 2012): 699–703. http://dx.doi.org/10.4028/www.scientific.net/amm.178-181.699.
Повний текст джерелаАнотація:
A denitrifying bacterium aHD7 with nitrate removal efficiency of 91.67% (w/w) in 3 days cultured at 30 °C under stationary conditions was isolated from the activated sludge. The strain was characterized by biochemical tests and 16S rDNA sequence analysis, to be belonging to Pseudomonas. Factors on denitrification ability of aHD7, i.e., pH value, carbon source, C/N ratio, nitrogen source and initial nitrate concentration were investigated. Results showed that this strain could either use nitrate or nitrite as the electron acceptor, and the total inorganic nitrogen removal efficiency for sodium nitrite and potassium nitrate were up to 96.70% (w/w) and 95.93% (w/w) respectively. Denitrification was favored when the pH value was 6-9 and C/N ratio varied from 6 to 8, in which the optimal carbon source was ethanol. The strain had anammox activity, of which the average ammonium utilization rate reached up to 4.56 mg/l/d.
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Zebarth, B. J., G. Tai, R. Tarn, H. de Jong, and P. H. Milburn. "Nitrogen use efficiency characteristics of commercial potato cultivars." Canadian Journal of Plant Science 84, no. 2 (April 1, 2004): 589–98. http://dx.doi.org/10.4141/p03-050.
Повний текст джерелаАнотація:
One approach for reducing the contribution of potato (Solanum tuberosum L.) production to nitrate contamination of groundwater is to develop cultivars which utilize N more efficiently. In this study, variation in N use efficiency (NUE; dry matter production per unit crop N supply) characteristics of 20 commercial potato cultivars of North American and European origin were evaluated in 2 yr. Cultivars were grown with or without application of 100 kg N ha-1 as ammonium nitrate banded at planting. The recommended within-row spacing was used for each cultivar and no irrigation was applied. Plant dry matter and N accumulation were determined prior to significant leaf senescence. Crop N supply was estimated as fertilizer N applied plus soil inorganic N measured at planting plus apparent net soil N mineralization. Nitrogen use efficiency decreased curvilinearly with increasing crop N supply. Nitrogen use efficiency was lower for early-maturing cultivars compared to mid-season and late-maturing cultivars. A curvilinear relationship was obtained between plant dry matter accumulation and plant N accumulation using data for all cultivars. Deviations from this relationship were interpreted as variation in N utilization efficiency (NUtE; dry matter accumulation per unit N accumulation). Significant differences in NUtE were measured among cultivars of similar maturity. Nitrogen uptake efficiency (NUpE; plant N content per unit crop N supply) and soil nitrate concentration measured at plant harvest were uniformly low for all cultivars when crop N supply was limited, but varied among cultivars when N was more abundant. This suggests that potato cultivars vary more in terms of N uptake capacity (plant N accumulation in the presence of an abundant N supply) than in terms of NUpE. Key words: Solanum tuberosum, N mineralization, dry matter accumulation, N accumulation, N utilization efficiency
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Colla, Giuseppe, Carolina María Cardona Suárez, Mariateresa Cardarelli, and Youssef Rouphael. "Improving Nitrogen Use Efficiency in Melon by Grafting." HortScience 45, no. 4 (April 2010): 559–65. http://dx.doi.org/10.21273/hortsci.45.4.559.
Повний текст джерелаАнотація:
Identification of rootstocks capable of improving the nitrogen use efficiency (NUE) of the scion could reduce N fertilization and nitrate leaching; however, screening different graft combinations under field conditions can be costly and time-consuming. This study evaluated a rapid and economical methodology for screening of melon rootstocks for NUE. Two experiments were designed. In the first, melon plants (Cucumis melo L. cv. Proteo) either ungrafted or grafted onto four commercial rootstocks: ‘Dinero’ and ‘Jador’ (Cucumis melo L.), ‘P360’, and ‘PS1313’ (Cucurbita maxima Duchesne × Cucurbita moschata Duchesne) grown in hydroponics were compared in terms of shoot dry biomass, leaf area, root-to-shoot ratio, SPAD index, shoot N uptake, and nitrate reductase (NR) activity at the early developmental stage in response to nitrate availability (0.5, 2.5, 5, 10, or 15 mm of NO3–). The second experiment was aimed to confirm whether the use of a selected rootstock with high NUE (‘P360’) could improve crop performance and NUE of grafted melon plants under field conditions. In the first experiment, carried out under greenhouse conditions, melon plants grafted onto ‘Dinero’, ‘Jador’, and ‘P360’ rootstocks needed 5.7, 5.2, and 6.1 mm of NO3–, respectively, to reach half-maximum shoot dry weight, whereas plants grafted onto ‘PS1313’ rootstock and the control treatment (ungrafted plants) needed 9.1 and 13.1 mm of NO3–, respectively. Total leaf area, SPAD index, and shoot N uptake increased linearly and quadratically in response to an increase of the N concentration in the nutrient solution. At 2.5 mm of NO3–, melon plants grafted onto both C. melo and Cucurbita maxima × Cucurbita moschata rootstocks had the highest NR activity, whereas no significant difference was observed at 10 mm of NO3–. In the second experiment, carried out under open field conditions, increasing the N fertilization rates from 0 to 120 kg·ha−1 increased the total and marketable yields of melon plants, whereas the NUE decreased. When averaged over N levels, the marketable yield, NUE, and N uptake efficiency were higher by 9%, 11.8%, and 16.3%, respectively, in ‘Proteo’ grafted onto ‘P360’ than in ungrafted ‘Proteo’ plants.
Дисертації з теми "Nitrate use efficiency"
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Zhang, Chenxi. "Nitrate Uptake of Kentucky Bluegrass as a Determinant of Nitrogen Use Efficiency." Thesis, North Carolina State University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3538535.
Повний текст джерелаАнотація:
Nitrate (NO3-) leaching from fertilized land can be detrimental to aquatic ecosystems and human health. Although NO 3- leaching potential is generally found to be low in turfgrass, certain conditions can occur that result in increased leaching loss of nitrogen. Kentucky bluegrass (Poa pratensis L.) is the most widely used cool-season turfgrass species in the temperate and subarctic climate zones in the United States. Due to its popularity, many new cultivars are bred and released each year. Despite the ample amount of information characterizing the agronomic features of Kentucky bluegrass genotypes, little is available documenting their physiological characteristics related to nitrogen use efficiency and how these might affect the NO3 - leaching potential of the genotypes. Such information would be of great value for both scientists and customers.
In this comprehensive study, a screening procedure was developed using nutrient solution culture to evaluate differences in NO3 - uptake among sixty Kentucky bluegrass genotypes. Two cultivars were selected from the sixty to represent genotypes having high vs. low capacity for NO3- uptake. These two cultivars were then used to examine the relationship between NO3- uptake efficiency and competitiveness for soil nitrogen. Finally, these two cultivars were compared to determine if NO3- uptake efficiency affected NO3- leaching potential.
There were significant differences in NO3- uptake at both high (1 mM) and low (0.05 mM) N concentrations among sixty Kentucky bluegrass genotypes, with a strong correlation between uptake rates at high and low N concentrations. Julia and Midnight were selected as representing cultivars with efficient and inefficient nitrate uptake, respectively. In nutrient solution culture, Julia exhibited 56% higher NO3 - uptake rates than Midnight. In a root competition study, in which the root systems of the two cultivars occupied the same soil volume, Julia was more competitive for nitrogen acquisition (absorbed 20 to 71% more NO 3- ) than Midnight. However, the higher NO3 - uptake capacity and better competitiveness for soil N in Julia did not result in lower NO3- leaching potential. These results suggest that differences in root morphology and architecture may play a more important role than uptake capacity in determining nitrate leaching potential among Kentucky bluegrass genotypes.
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Souza, Elialdo Alves de. "Aplicação de fertilizante amoniacal como estratégia para melhorar a eficiência de uso do fósforo em milho." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/151044.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
A aplicação de amônio pode, em algumas condições, melhorar a eficiência de uso do fósforo (EUP) e o desenvolvimento do milho, especialmente em solos tropicais, normalmente ácidos e pobres em P disponível. O presente trabalho tem por objetivo estudar o efeito da adubação amoniacal sobre o aproveitamento do P, as condições bioquímicas da rizosfera, a morfologia radicular e o desenvolvimento da cultura do milho. Os dois experimentos iniciais foram conduzidos em casa de vegetação, o primeiro em vasos de 12 L e o segundo em Plant Growth Containers (PGCs), com solo previamente corrigido e adubado segundo os tratamentos: 3 (três formas de adubação nitrogenada - amoniacal, nítrica e mista) x cinco doses de fosfato (0, 40, 80, 120 e 160 mg P kg-1 de solo). Aos 35 dias após a emergência as raízes foram removidas dos containers e vasos e as amostras de planta e solo foram coletadas para análises. O solo rizosférico no experimento I foi obtido por “agitação-lavagem” e no experimento II por “fatiamento em camadas”, de forma que quatro das oito repetições foram congeladas frescas (análises: amônio, nitrato, C orgânico e P microbiano) e quatro foram transformadas em TFSE (análises: fracionamento químico do P e pH). As amostras de planta foram submetidas a pesagem e análise nutricional. O experimento III foi conduzido em um sistema de scanners em solução nutritiva de acordo com os tratamentos: 2 (amônio ou nitrato) x (alta dose ou baixa dose de P), com 10 repetições. Imagens foram obtidas diariamente para avaliação do desenvolvimento radicular. Ao final dos ensaios foram obtidos peso fresco e seco, análises de P em tecidos e, com dados de diferentes parâmetros radiculares, foi feito o desenho da planta média no RootBox. Os tratamentos com amônio e nitrato + amônio, na dose mais alta de P no experimento I ou em todas as doses no experimento II, resultaram em maior produção de matéria seca, menor relação raiz: parte aérea, desenvolvimento de raiz mais aequado à absorção de P, maior recuperação de P, maior acúmulo de amônio, nitrato e N-mineral nas camadas mais próximas ao rizoplano, menor pH, maior mobilização de formas menos lábeis de P, maior consumo de P geoquímico e P biológico. Houve diferença entre solo rizosférico e solo não rizosférico e entre as diferentes camadas da rizosfera, para todos os parâmetros, entre as formas de nitrogênio. O amônio e nitrato + amônio resultaram em maior produção de C orgânico solúvel em água e maior dose de superfosfato triplo resultou em maior quantidade de P na fração microbiana. O amônio resultou desenvolvimento radicular mais ramificado e com maior número de raízes laterais. O amônio melhora a eficiência de uso do P, devido às mudanças químicas e biológicas na rizosfera, e às mudanças na arquitetura radicular, que favorecem a solubilidade, a mineralização e a absorção de fosfato e, consequentemente, aumenta a produção de matéria seca nos estádios iniciais da cultura do milho.
Ammonium application can improve phosphorus use efficiency (PUE) and the development of maize plants, especially in tropical soils, usually acids and P-limiting. The aim of this study is evaluate how ammoniacal fertilization impacts the P use efficiency (PUE), the biochemical conditions of the rhizosphere, the root morphology and the development of maize plants. Two initial experiments were carried on greenhouse, the first one in pots of 20 L and the second one in Plant Growth Containers (PGCs), using soil after liming and fertilized according to the following treatments: 3 (nitrogen fertilization: ammonium only, nitrate only and both) x five doses of phosphate (0, 40, 80, 120 and 160 mg P kg-1 of soil). At 35 days after emergence the roots were removed from the containers and pots and the plant and soil samples were collected for analysis. The rhizosphere soil in experiment I was obtained by "shaking-washing" and in the experiment II by "layer slicing". Four of the eight soil replicates were fresh frozen (analyzes: ammonium, nitrate, organic C and microbial P) and four of them were dried (analyzes: chemical fractionation of P and pH). Plant samples were weighed and analyzed for P content. The experiment III was carried on a system of nutrient solution scanners according to the treatments: 2 (ammonium or nitrate) x (high or low dose of P), with 10 replicates. Images were obtained in daily basis for the evaluation of root development. At the end of the tests, fresh and dry weights and P content were obtained. Data of different root traits were used to draw the average plant on the RootBox. The treatments with ammonium and nitrate + ammonium, plus the highest dose of P in the experiment I or at all doses in the experiment II, resulted in higher dry matter yield, lower root ratio: aerial part, root development adequate for P absorption, higher P recovering, higher ammonium, nitrate and N-mineral accumulation in the nearest layersto the rhizoplane, lower pH, greater mobilization of less labile P forms, higher mobilization of geochemical and biological P. There were differences between rhizospheric and bulk soils and between the different layers of the rhizosphere, for all parameters and treatments. Ammonium and nitrate + ammonium resulted in higher organic C water soluble organic C, and higher dose of triple superphosphate resulted in higher amount of P in the microbial fraction. Ammonium resulted in a branched root with a greater number of lateral roots. Ammonium improves the use efficiency, solubility, mineralization and uptake of P, due to chemical and biological changes in the rhizosphere and root architecture in the early stages of corn development.
FAPESP: 13/18870-1
FAPESP: 15/12399-0
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Borges, Bernardo Melo Montes Nogueira [UNESP]. "Efficiency of nitrogen sources and rates on growth and dry matter yield of tifton 85." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/138169.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Forrageiras do gênero Cynodon são conhecidas por sua capacidade de resposta a altas doses de nitrogênio (N). Em condições tropicais o N pode se tornar um problema ambiental e financeiro devido à sua baixa eficiência de uso pelas plantas, principalmente como resultado de perdas por volatilização e/ou lixiviação. Portanto, objetivou-se com este trabalho avaliar fontes e doses de N no crescimento e produção de matéria seca do Tifton 85, bem como mudanças nas frações do carbono (C) no solo. Um experimento foi conduzido de 2012 a 2014, e constituiu de um fatorial em um delineamento de blocos ao acaso, onde os tratamentos foram a associação de duas fontes de N (nitrato de amônio [NA] e ureia), e cinco doses do nutriente (0, 60, 120, 180 e 240 kg ha-1 N por corte) aplicadas a cada 30 dias. Neste experimento foram utilizados NA e ureia enriquecidos com 15N como uma ferramenta para quantificar a recuperação do N advindo do fertilizante, nas plantas e no sistema solo-planta. As plantas foram cortadas para avaliar a produção de matéria seca, concentração de N na parte aérea e recuperação. O índice de área foliar (LAI), radiação fotossinteticamente ativa interceptada (PARi) e índice de clorofila (CI) foram mensurados no dia anterior ao corte. As amostras de solo foram coletadas nas parcelas que receberam NA e foram fracionadas em carbono orgânico particulado (POC), fração leve livre (FLF) e fração mineral (C-min); O teor de C nas frações foi quantificado. Os resultados demonstraram que o NA pode ser uma fonte mais eficiente somente quando a quantidade de precipitação é insuficiente para incorporar o fertilizante ao solo, resultando em maior produção de forragem, na somatória dos dois anos ambas as fontes produziram a mesma quantidade de matéria seca onde a maior produtividade 37,2 Mg ha-1, foi atingida com a dose de 210 kg ha-1 N por corte. Por outro lado, a quantidade de N recuperado pelo sistema de planta+solo foi maior quando a ureia foi utilizada, com destaque para a quantidade de N no solo, onde a ureia foi capaz de manter 10% mais N que o NA, a recuperação do nutriente diminuiu à medida que as doses foram elevadas. Nenhuma alteração no conteúdo de C foi notada devido às diferentes doses de N utilizadas, no entanto o POC e o C-min foram mais sensíveis às mudanças na camada de 0-0,1 m do que na camada de 0,1-0,2 m.
Cynodon hybrids are known by their ability to respond to high rates of nitrogen (N). In tropical conditions, N may become an environmental and financial issue due to its low efficiency of use by plants, mainly as a result of losses by volatilization and/or leaching. Therefore, the aims with this work were to evaluate N sources and rates on growth and dry matter yield of Tifton 85 and to determine changes in soil carbon (C) fractions in response to N fertilization. The 2-yr field experiment was conducted from 2012 to 2014, and consisted of a factorial design. Treatments were a combination of two sources of N (ammonium nitrate [AN] and urea) and five rates of the nutrient (0, 60, 120, 180 and 240 kg ha-1 N per cut) applied broadcast every 30 days. This study used AN and urea enriched with 15N as a tool to quantify the recovery of N derived from fertilizer in plants and the soil-plant system. Forage was cut at 30-d intervals for dry matter yield, shoot N concentration determinations and N recovery. The leaf area index (LAI), photosynthetic active radiation intercepted (PARi) and chlorophyll index (CI) were evaluated on the day before clipping. Soil samples were collected in plots receiving AN and they were fractionated in to particulate organic carbon (POC), free light fraction (FLF) and mineral fraction (C-min); The C concentration of the various fractions was determined. Results showed that AN was a more efficient source only when the amount of precipitation is insufficient to incorporate the fertilizer to the soil, resulting in increased production, in the sum of the two years both sources produced the same amount of dry matter in which the highest productivity, 37.2 t ha-1 , was achieved at the rate of 210 kg ha-1 N per cutting. On the other hand, the amount of N recovered by the plant+soil system was higher when urea was used, especially the amount of N in the soil, where urea was able to maintain 10% more N than AN, the nutrient recovery decreased as the rates were increased. No change in soil C concentration was detected in response to the different N rates used, however the POC and the C-min were more sensitive to changes in the layer of 0-0.1 m than the layer from 0.1-0.2 m.
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Paulo, Ezio Nalin de. "Avaliação do inibidor de nitrificação fosfato de 3,4-dimetilpirazol (DMPP) em três solos com gradiente textural, absorção e uso de nitrogênio em plantas de algodão." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/64/64133/tde-17012013-140846/.
Повний текст джерелаАнотація:
A utilização de inibidores de nitrificação pode ser uma alternativa interessante para aumentar a eficiência do uso do fertilizante nitrogenado em diversas culturas, porém, essa alternativa vem sendo pouco estudada em condições de solo e clima do Brasil. Assim, objetivou-se com esse trabalho avaliar a eficiência do inibidor de nitrificação fosfato de 3,4-dimetilpirazol (DMPP) em três solos com gradiente textural, bem como avaliar o destino do nitrogênio (N-NO3-, N-NH4+ e 15N) no solo, a absorção e o uso do nitrogênio (N-total e 15N) nas plantas de algodão. Três experimentos foram montados e desenvolvidos. No primeiro foi efetuada a incubação do solo em condições de laboratório para avaliar a inibição da nitrificação pelo DMPP aplicado na forma de ureia e sulfonitrato de amônio (SNA) em três solos (Neossolo Quartzarênico - NQ, Latossolo Vermelho Amarelo - LVA, Latossolo Vermelho - LV). No segundo experimento plantas de algodão foram cultivadas em colunas de lixiviação com os mesmos solos, recebendo ureia e sulfonitrato de amônio, com e sem DMPP como fonte de N. Foram avaliados a produção de matéria seca, o acúmulo de nutrientes nas plantas, a eficiência de uso do N pelo algodoeiro, a lixiviação e a quantidade de N mineral no solo após o cultivo do algodão por 60 dias. No terceiro experimento, plantas de algodão foram cultivadas também em colunas lixiviação, porém, com um solo de textura média (Latossolo Vermelho Amarelo), o qual recebeu três doses de N em cobertura (50, 100 e 150 kg ha-1 de N) na forma de ureia marcada no isótopo 15N, com e sem DMPP. Foram avaliados a produção de matéria seca, teor de N e recuperação do N aplicado na planta, lixiviação de N, teor de N-total, nítrico e amoniacal no solo, e recuperação do N aplicado no solo após o cultivo do algodão, por 90 dias. Melhores resultados foram obtidos com a aplicação do DMPP em ureia em relação ao SNA. No experimento de incubação, o DMPP foi capaz de manter menor o teor de nitrato nos três solos analisados. A nitrificação do N na ureia foi mais rápida comparado ao SNA, o que permitiu melhor desempenho do inibidor na ureia em dois dos três solos estudados. O efeito do DMPP aumentou seguindo a seguinte ordem: NQ>LVA>LV. O inibidor foi mais eficiente nos solos com menor teor de argila e matéria orgânica. O uso do DMPP em ureia aplicada no solo arenoso (NQ) reduziu significativamente a lixiviação de N e aumentou a produção de matéria seca, a eficiência do uso do N e a absorção de fósforo pela planta. No solo de textura média (LVA), sob irrigação intensa, o DMPP reduziu significativamente as perdas de N do sistema e aumentou a recuperação do 15N aplicado na planta e no solo, o que, porém, não se traduziu em maior produção de matéria seca provavelmente pelo N não ter sido limitante, devido à mineralização da matéria orgânica. As atividades das enzimas redutase do nitrato e urease não diferiram entre tratamentos com e sem DMPPThe use of nitrification inhibitors may be an interesting alternative to increase nitrogen fertilizer use efficiency in different crops, although it has been little studied in soil and climate conditions of Brazil. This study aimed to evaluate the efficiency of the nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) in three soils with textural gradient (represented by clay percentage), as well as to evaluate the fate of soil nitrogen (N-NO3-, N-NH4+ and 15N), nitrogen uptake, and N-use efficiency (total-N and 15N) by cotton plants. Three experiments were set and carried out in a controlled environment. In the first one, a laboratory incubation was performed to evaluate the inhibition of nitrification by DMPP applied to urea and ammonium sulfate nitrate (ASN) in three soils (Typic Quartzipsammnet - NQ, Typic Hapludox - LVA, Rhodic Hapludox - LV). In the second experiment, leaching columns with the same soils were planted with cotton receiving ammonium sulfate nitrate and urea with or without DMPP as nitrogen source. It were evaluated plant dry matter yield (shoot plus roots), nutrient uptake and nitrogen use efficiency by cotton plants, as well as the nitrogen leaching, and mineral nitrogen amount in the soil after cotton growth, for 60 days. In the third experiment, leaching columns with a medium textured soil (LVA) were planted with cotton and received three nitrogen rates in topdressing (50, 100 and 150 kg ha-1) as 15N-urea with and without DMPP. The production of dry matter, nitrogen content and recovery of applied N in the plant and soil, as well as the nitrogen leaching, total nitrogen, nitrate and ammonium in the soil were evaluated after cotton growth for 90 days. Best results were obtained with the application of DMPP to urea than in ASN. In the incubation experiment, the DMPP was able to maintain lower nitrate content in the three soils. The nitrification of nitrogen from urea was faster than the one from ASN, which allowed a better performance of the inhibitor in the urea in two out of three soils analyzed. The effect of DMPP increased in the following order: NQ> LVA> LV. The inhibitor was more effective in soils with lower clay and organic matter contents. The use of DMPP in urea applied on the sandy soil (NQ) significantly reduced N leaching and increased dry matter production, nitrogen use efficiency and phosphorus uptake by cotton plants. In a medium textured soil (LVA) under intense irrigation, DMPP significantly reduced N losses in the system and increased the recovery of applied 15N in plant and soil, which however did not translate into higher dry matter production because nitrogen was probably not limiting. The activity of the enzymes nitrate reductase and urease were not different between treatments with and without DMPP
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Boschiero, Beatriz Nastaro. "Adubação nitrogenada em soqueiras de cana-de-açúcar: influência do uso em longo prazo de fontes e/ou doses de nitrogênio." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-23012017-103942/.
Повний текст джерелаАнотація:
O uso de determinadas fontes nitrogenadas, doses e formas de nitrogênio (N) pode aumentar a eficiência de uso de N (EUN) em soqueiras de cana-de-açúcar (Saccharum spp.), mantendo, em longo prazo, elevados índices de produtividade, lucro e proteção ao ambiente. Experimentos de campo e de casa-de-vegetação foram desenvolvidos com os seguintes objetivos: (i) avaliar o efeito do manejo do N-fertilizante e dos ciclos de soqueira da cultura na produtividade, parâmetros tecnológicos, acúmulo de biomassa, acúmulo e balanço de nutrientes e nas alterações dos atributos químicos do solo; (ii) avaliar a produção de biomassa seca, metabolismo e nutrição de plantas de cana-de-açúcar cultivadas em solução nutritiva, com suprimento exclusivo ou misto de nitrato (NO3-) e amônio (NH4+) como fontes de N; (iii) avaliar a EUN do 15N-nitrato (15NH4NO3), 15N-amônio (NH415NO3) e 15N-amida [(15NH2)2CO] aplicados na quarta soqueira de cana-de-açúcar em condições de campo; e avaliar a EUN do 15N-amônio e 15N-nitrato aplicados em mudas de cana-de-açúcar cultivadas em solução nutritiva. No campo, o N-fertilizante foi repetido nas mesmas parcelas experimentais (parcelas estáticas), em anos subsequentes (quatro ou cinco soqueiras) e o manejo de N-fertilizante, que incluiu fontes e doses de N, não influenciou na produtividade de colmos e de açúcar no local 1 (Latossolo Vermelho Amarelo distrófico - LVAd). Entretanto, no local 2 (também LVAd), o NA100 e o NAC100 [nitrato de amônio (NA) e nitrato de amônio e cálcio (NAC), ambos na dose de 100 kg ha-1 de N] foram os manejos mais vantajosos para a obtenção das maiores produtividades de colmo e de açúcar em soqueiras quando comparado aos demais tratamentos. No geral, nos dois locais, o NAC150 (150 kg ha-1 de N) proporcionou os maiores acúmulos de biomassa, N e K nas plantas. Além disso, enquanto o controle (sem adição de N) apresentou as menores produções de biomassa e acúmulos de nutrientes (com exceção ao P), o balanço de nutrientes do solo nesse tratamento foi relativamente neutro após anos de cultivo da cana-de-açúcar. Em condições controladas, plantas de cana-de-açúcar supridas exclusivamente com amônio apresentaram menor produção de biomassa, acúmulo de nutrientes e área foliar do que os outros tratamentos (supridos com combinações de NO3-/NH4+ e somente com nitrato), indicando que o uso exclusivo dessa forma de N não foi eficiente para sustentar o crescimento vegetal. A maior EUN foi obtida com o fornecimento exclusivo de nitrato, que também proporcionou maior produção de biomassa seca, área foliar, acúmulo de macronutrientes, atividade fotossintética e crescimento do sistema radicular. A utilização de 15N indicou que, no campo, não houve diferença na EUN pelas plantas devido à utilização do 15N-nitrato e 15N-amônio. Em contraste, a EUN do 15N-amônio foi maior que a do 15N-nitrato durante o 1º, 4º e 7º dia após a aplicação do fertilizante (DAAF), em condições controladas. Contudo, o uso do 15N-nitrato teve maior EUN nas raízes e planta inteira que o 15N-amônio no 15º DAAF. Isso indica que a cana-de-açúcar pode aproveitar eficientemente as duas formas minerais de N, embora o aproveitamento do amônio seja mais rápido.The use of different fertilizers and rates of nitrogen (N) can increase the N use efficiency (NUE) in sugarcane ratoon (Saccharum spp.), sustaining high yield levels, profitability and environmental protection in long-term. Thus, field and greenhouse studies were performed with the following objectives: (i) evaluate the effect of fertilizer-N management and ratoon crop cycles on sugarcane yield, technological parameters, biomass accumulation, nutrient content, temporal variation in soil chemical properties and soil nutrient balance; (ii) evaluate the biomass production, metabolism and nutrient acquisition of sugarcane plants cropped in nutrient solution, with solely or combined supply of ammonium and nitrate as N sources; (iii) evaluate the NUE of 15N-ammonium (15NH4NO3), 15N-nitrate (NH415NO3), and 15N-amide [(15NH2)2CO] applied to sugarcane under field conditions and the NUE of 15N-ammonium and 15N-nitrate applied to seedlings sugarcane under nutrient solutions. In the field, N fertilizers were replicated in the same experimental plots (static plots) in subsequent years (four or five ratoons) and the management of N-fertilizer, which included fertilizers and N rates, resulted in lack of influence on cane and sucrose yield at Site 1 (Typic Hapludox). However, at Site 2 (also Typic Hapludox), the N treatments AN100 and CAN100 [ammonium nitrate (AN) and calcium ammonium nitrate (CAN), both at a rate of 100 kg N ha-1] provided the highest cane and sugar yield as compared to the remaining treatments. Overall, at both sites, CAN150 (150 kg N ha-1) resulted in the highest biomass accumulation and N and K content by sugarcane. In addition, while the control (no N added) had the lowest biomass accumulation and nutrient content (except for P), the soil nutrient balance in this treatment was relatively neutral, after years of sugarcane cultivation. Under controlled conditions, NH4+-fed plants presented lower biomass accumulation, nutrient content and leaf area than the other treatments (different NO3-/NH4+ ratios and NO3--fed plants), indicating that this N form, when applied solely, was not effective for the proper plant growth. The highest NUE was obtained with NO3--fed plants, which also had the highest production of dry biomass, leaf area, nutrient accumulation, photosynthetic activity, and growth of the root system. The use of 15N-nitrate and 15N-ammonium indicated that there was no difference in NUE by plants in the field. In contrast, the NUE of 15N-ammonium was greater than 15N-nitrate during the 1st, 4th and 7th day after fertilizer application (DAFA), under controlled conditions. However, the use of 15N-nitrate had greater NUE in roots and whole plant than 15N-ammonium in the 15th DAFA. It can be concluded that sugarcane can use both N forms although the recovery of NH4+ was faster than NO3-.
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Fernandes, Flavia Carvalho Silva. "Dinâmica do nitrogênio na cultura do milho (Zea mays L.), em cultivo sucessivo com aveia preta (Avena strigosa), sob implantação do sistema plantio direto." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-05042006-144028/.
Повний текст джерелаАнотація:
O presente trabalho foi desenvolvido na área experimental da ESALQ-USP, localizada no município de Piracicaba/SP, em um Latossolo Vermelho Amarelo, textura areno-argiloso. O experimento teve como objetivo estudar a dinâmica do N no sistema solo-planta da cultura do milho, sob implantação do sistema plantio direto, e, pela técnica do 15N, avaliar a lixiviação de nitrato à profundidade de 0,80 m, a eficiência de utilização do N e o efeito residual do fertilizante nas culturas subseqüentes. O projeto envolveu dois cultivos de milho e um de aveia preta, cultivada na entressafra. O delineamento experimental foi o de blocos casualizados (3x2), com 4 repetições. Os tratamentos consistiram de doses de nitrogênio, na forma de sulfato de amônio (60, 120 e 180 kg ha-1 de N) e uma testemunha, além dos parcelamentos (30 kg ha-1 de N na semeadura e o restante em cobertura; 60 kg ha-1 de N na semeadura e o restante em cobertura). A aplicação de sulfato de amônio enriquecido com 15N foi feita, na dose de 120 kg ha-1 de N, em subparcelas, previamente definidas, apenas no primeiro cultivo do milho. Foram feitas as seguintes avaliações: densidade de fluxo de água e de nitrato na profundidade de 0,80 m do solo (dose de 120 kg ha-1 de N); massa de 100 grãos; massa de matéria seca; teor de N; rendimento de grãos de milho; átomos % 15N nas plantas e solo; fração do N fertilizante na solução do solo na profundidade de 0,80 m, e no perfil do solo; balanço do N na sucessão de culturas; efeito residual do N fertilizante (aplicado no primeiro cultivo de milho) na aveia e no segundo cultivo de milho. Pelos resultados obtidos, concluiu-se que: a) a perda de nitrato total por lixiviação, a 0,80 m de profundidade, no 1º cultivo de milho, na dose de 120 kg ha-1 de N, foi de aproximadamente 96 e 68 kg ha-1, para os parcelamentos com 60 kg ha-1 e 30 kg ha-1 de N na semeadura, respectivamente, dos quais apenas 3 e 1 kg ha-1 foram provenientes do fertilizante nitrogenado; b) na dose 120 kg ha-1 de N, o tratamento com maior quantidade de N aplicado na semeadura (60 kg ha-1), no cultivo de milho do ano agrícola 2003/2004, proporcionou um maior aproveitamento do N do fertilizante (65%), em relação ao tratamento com a dose de 30 kg ha-1 na semeadura (45%) e que, para esse ano, a recuperação do N fertilizante pelo solo, na camada 0-0,80 m, para ambos os tratamentos, 60-60 e 30-90 kg ha-1, foi de 40 e 49%, respectivamente; c) Ainda referindo-se aos tratamentos 60-60 e 30-90 kg ha-1, do N remanescente do sulfato de amônio (120 kg ha-1), aplicado no primeiro ano agrícola (efeito residual), 3,72 e 1,79% foram utilizados pela aveia preta e 2,84 e 2,06% pelo milho cultivado no ano subseqüente (2004/2005), permanecendo no solo (camada 0-0,80 m), 30,19 e 33,47% após o cultivo de aveia preta e 16,79 e 17,91% após o segundo cultivo de milho, respectivamente, para os referidos tratamentos.The general objective of this work was to study the dynamics of nitrogen in the soil-plant system of two maize crops with a black oats one in between, introducing the no-tillage system. Besides, fertilizing the first maize crop with 15N enriched nitrogen fertilizer, it was also objective of this work to assess the total and the derived from fertilizer nitrate leached at the depth of 0.8 m, the nitrogen use efficiency by the crops and the residual effect of the labeled nitrogen fertilizer. The experiment was carried in the experimental areas of ESALQ-USP in the country of Piracicaba (SP), in a yellow red latossol, sandy-loamy texture. The first maize crop was in 2003/2004 and the second one in 2004/2005. The experimental design was randomized blocks (3 x 2), with four replications. Treatments consisted of nitrogen (as ammonium sulphate) levels (60, 120 and 180 kg ha-1 of nitrogen) and the control, besides the splittings (30 and 60 kg ha-1 of nitrogen in the sowing and the rest in covering). The fertilization with 15N enriched ammonium sulphate in the first maize crop was made only for the level of 120 kg ha-1 of nitrogen, in subplots previously defined. The following measurements were carried out: soil-water and nitrate flux densities at the depth of 0.8 m (120 kg ha-1 of N); weight of 100 grains; weight of plant dry matter; nitrogen content; grain yield; total nitrogen; plant nitrogen use efficiency; fraction of the applied nitrogen in the soil solution at the depth of 0.8 m and in the soil profile; nitrogen balance in the crops succession; nitrogen residual effect in the black oat and the second maize crop. From the results, it could be concluded that: a) the leaching losses of total N, at the depth of 0,80 m, in the first maize crop, at the fertilization level of 120 kg ha-1 of N, were of 96 and 68 kg ha-1 for the splittings 60 and 30 kg ha-1 of N at sowing, respectively, from which only 3 and 1 kg ha-1 were derived from the nitrogen fertilizer; b) at the N fertilization level of 120 kg ha-1, the treatment with higher amount of applied N at sowing (60 kg ha-1) of the first maize crop (2003/2004) led to a higher plant N fertilizer recovery (65%) than the 30 kg ha-1of applied N at the sowing treatment (45%) and that, at the end of this crop cycle, the N fertilizer recovery by the 0-0,80 m soil layer, for 60-60 and 30-90 kg ha-1 treatments, were 40 and 49%, respectively; c) still for treatments 60-60 and 30-90 kg ha-1, from the total N applied in the first maize crop (120 kg ha-1), 3.72 and 1.79% were used by the black oats and 2.84 and 2.06% by the second maize crop, remaining in the soil (0-0.8 m layer), 30.19 and 33.47% after the black oats crop and 16.79 and 17.91% after the second maize crop, respectively for 60-60 and 30-90 kg ha-1 of N treatments.
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Ferchaud, Fabien. "Etude des bilans d’eau, d’azote et de carbone dans des agrosystèmes dédiés à la production de biomasse en fonction des espèces et des pratiques culturales." Thesis, Paris, AgroParisTech, 2015. http://www.theses.fr/2015AGPT0037.
Повний текст джерелаАнотація:
Les biocarburants de 2ème génération pourraient fournir une énergie renouvelable au secteur des transports et ainsi permettre de lutter contre le changement climatique. Toutefois, leurs bilans gaz à effet de serre, énergétiques et environnementaux seront probablement très dépendants des ressources utilisées. Les cultures lignocellulosiques candidates à la production de biocarburant 2G devront ainsi concilier forte productivité, faibles besoins en intrants et faibles impacts environnementaux. L’objectif de la thèse a été de quantifier les bilans d’eau, d’azote et de carbone à l’échelle de la parcelle, pour différentes cultures candidates et différentes pratiques culturales. Nous nous sommes appuyés sur le dispositif expérimental de long terme « Biomasse & Environnement », mis en place en 2006 à Estrées-Mons, en Picardie. Il compare deux cultures pérennes en C4 (Miscanthus × giganteus et switchgrass), deux cultures pluriannuelles fourragères en C3 (fétuque et luzerne) et deux cultures annuelles récoltées en plante entière (sorgho fibre et triticale). Il inclut deux niveaux de fertilisation et deux dates de récolte pour les cultures pérennes : récolte précoce (octobre) ou récolte tardive (février). Les mesures effectuées ont porté sur : i) la production de biomasse, ii) l’évolution des stocks d’eau du sol en continu pendant 7 ans, iii) la profondeur et la densité des systèmes racinaires, iv) le drainage et la concentration en nitrate de l’eau drainée, évalués avec le modèle STICS à partir des stocks d’eau et d’azote minéral du sol mesurés en milieu d’automne et fin d’hiver, v) les stocks de carbone organique du sol en 2006 et 2011-2012, vi) le devenir de l’engrais azoté, suivi par marquage isotopique 15N de l'engrais pendant 4 ou 5 années successives.Grâce à leur enracinement profond, les cultures pérennes et pluriannuelles ont prélevé davantage d’eau que les cultures annuelles, notamment en profondeur. Le drainage sous les cultures pluriannuelles a été plus faible que sous les cultures annuelles (64 contre 133 mm an-1 en moyenne sur 7 ans), malgré une production de biomasse équivalente. Il a été intermédiaire pour les cultures pérennes (56-137 mm an-1) et très fortement lié à la production (elle-même fonction de l’espèce et de la fertilisation azotée). La concentration en nitrate a varié de 2 à 23 mg l-1. Elle a été en général plus faible sous les cultures pérennes, sauf pour le miscanthus lors de la première année de mesure. Les stocks de carbone du sol ont augmenté fortement sous les cultures pluriannuelles (+0.93 t C ha-1 an-1) mais n'ont pas varié significativement pour les autres cultures. Le 15N retrouvé dans la biomasse récoltée a été plus faible pour les cultures pérennes, particulièrement lorsqu’elles sont récoltées tardivement, mais cela est compensé par une plus forte proportion de 15N dans leurs organes souterrains et dans le sol. Le 15N retrouvé dans le système sol-plante a été de 69% de l’azote apporté pour les cultures pérennes, 61% pour les cultures pluriannuelles et 56% pour les cultures annuelles, ce qui suggère que des pertes importantes ont eu lieu par volatilisation et dénitrification. Dans nos conditions pédoclimatiques, les cultures pérennes en C4 sont les plus intéressantes pour concilier forte production de biomasse, forte efficience d’utilisation de l’eau et de l’azote et faibles pertes d’azote vers l’hydrosphère et l’atmosphère. En revanche, seules les cultures pluriannuelles permettent de stocker du carbone à court termeSecond generation biofuels could provide renewable energy to the transportation sector while mitigating climate change. However, their greenhouse gas, energy and environmental balances will probably depend on the feedstock used for their production. Bioenergy crops that could be used for second generation biofuels will have to fulfil several requirements, including high productivity, low input requirements, and low environmental impacts. The objective of this work was to assess the water, N and C balances at the plot scale for various bioenergy crops with different management. The study is based on a long term field experiment, called “Biomass & Environment”, established at the INRA experimental station in Estrées-Mons, northern France. This experiment includes two perennial C4 crops (Miscanthus × giganteus and switchgrass), two semi-perennial forage C3 crops (fescue and alfalfa) and two annual C4/C3 crops (fibre sorghum and triticale). It compares two nitrogen treatments and two dates of harvest of perennial crops: early (October) or late harvest (February). Measurements have been carried out on: i) biomass production; ii) soil water stocks, monitored continuously during 7 years; iii) root depth and density; iv) drainage and nitrate concentration in drained water, assessed from soil water and mineral N content measurements (in mid-autumn and late winter) and using the STICS model; v) soil organic carbon (SOC) stocks in 2006 and 2011-2012; vi) the fate of 15N-labelled fertiliser applied during 4 or 5 successive years.Thanks to their deep rooting system, perennial and semi-perennial crops consumed more water than annual crops. The amount of drained water was lower under semi-perennial than annual crops (64 vs. 133 mm yr-1 average over 7 years), despite an equivalent biomass production. It was intermediate under perennial crops (56-137 mm yr-1) and negatively correlated to biomass production, itself depending on crop species and N rate. Nitrate concentration in drained water varied between 2 and 23 mg l-1. It was generally lower under perennial than other crops, except for miscanthus on the first year of measurement. SOC stocks increased markedly over time under semi-perennial crops (+0.93 t C ha-1 yr-1), whereas no significant change occurred under perennial and annual crops. The 15N recovery in the harvested biomass was lower for perennial than other crops, particularly when harvested late, but compensated by a higher 15N recovery in belowground organs and soil. The overall 15N recovery in the soil-plant system was 69% in perennials, 61% in semi-perennials and 56% in annual crops, suggesting that important fertiliser losses occurred through volatilisation and denitrification. In our pedo-climatic conditions, the C4 perennial crops performed best in terms of production, water and nitrogen use efficiency, and nitrogen losses towards the groundwater and the atmosphere. However, only semi-perennial crops yielded in SOC sequestration
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Borges, Bernardo Melo Montes Nogueira. "Efficiency of nitrogen sources and rates on growth and dry matter yield of tifton 85 /." Jaboticabal, 2016. http://hdl.handle.net/11449/138169.
Повний текст джерелаАнотація:
Orientador: Edson Luiz Mendes Coutinho CoutinhoCoorientador: Takashi Muraoka
Banca: Henrique Coutinho Junqueira Franco
Banca: Valdeci Orioli Júnior
Banca: José Eduardo Corá
Banca: Carolina Fernandes
Resumo: Forrageiras do gênero Cynodon são conhecidas por sua capacidade de resposta a altas doses de nitrogênio (N). Em condições tropicais o N pode se tornar um problema ambiental e financeiro devido à sua baixa eficiência de uso pelas plantas, principalmente como resultado de perdas por volatilização e/ou lixiviação. Portanto, objetivou-se com este trabalho avaliar fontes e doses de N no crescimento e produção de matéria seca do Tifton 85, bem como mudanças nas frações do carbono (C) no solo. Um experimento foi conduzido de 2012 a 2014, e constituiu de um fatorial em um delineamento de blocos ao acaso, onde os tratamentos foram a associação de duas fontes de N (nitrato de amônio [NA] e ureia), e cinco doses do nutriente (0, 60, 120, 180 e 240 kg ha-1 N por corte) aplicadas a cada 30 dias. Neste experimento foram utilizados NA e ureia enriquecidos com 15N como uma ferramenta para quantificar a recuperação do N advindo do fertilizante, nas plantas e no sistema solo-planta. As plantas foram cortadas para avaliar a produção de matéria seca, concentração de N na parte aérea e recuperação. O índice de área foliar (LAI), radiação fotossinteticamente ativa interceptada (PARi) e índice de clorofila (CI) foram mensurados no dia anterior ao corte. As amostras de solo foram coletadas nas parcelas que receberam NA e foram fracionadas em carbono orgânico particulado (POC), fração leve livre (FLF) e fração mineral (C-min); O teor de C nas frações foi quantificado. Os resultados demonstraram que o... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Cynodon hybrids are known by their ability to respond to high rates of nitrogen (N). In tropical conditions, N may become an environmental and financial issue due to its low efficiency of use by plants, mainly as a result of losses by volatilization and/or leaching. Therefore, the aims with this work were to evaluate N sources and rates on growth and dry matter yield of Tifton 85 and to determine changes in soil carbon (C) fractions in response to N fertilization. The 2-yr field experiment was conducted from 2012 to 2014, and consisted of a factorial design. Treatments were a combination of two sources of N (ammonium nitrate [AN] and urea) and five rates of the nutrient (0, 60, 120, 180 and 240 kg ha-1 N per cut) applied broadcast every 30 days. This study used AN and urea enriched with 15N as a tool to quantify the recovery of N derived from fertilizer in plants and the soil-plant system. Forage was cut at 30-d intervals for dry matter yield, shoot N concentration determinations and N recovery. The leaf area index (LAI), photosynthetic active radiation intercepted (PARi) and chlorophyll index (CI) were evaluated on the day before clipping. Soil samples were collected in plots receiving AN and they were fractionated in to particulate organic carbon (POC), free light fraction (FLF) and mineral fraction (C-min); The C concentration of the various fractions was determined. Results showed that AN was a more efficient source only when the amount of precipitation is insufficient to... (Complete abstract click electronic access below)
Doutor
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Bucher, Carlos Alberto. "Express?o de genes relacionados ? absor??o e metabolismo de nitrog?nio em arroz sob alto e baixo suprimento de nitrato." Universidade Federal Rural do Rio de Janeiro, 2011. https://tede.ufrrj.br/jspui/handle/jspui/1163.
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Funda??o Carlos Chagas Filho de Amparo ? Pesquisa do Estado do RJ - FAPERJ
Nitrogen is one of the nutrient elements most limiting for plant growth. Thus, increasing plant nitrogen usage efficiency (NUE) is an essential factor for sustainable agriculture, leading to an increased food production with less fertilizer input and less environment impact. NUE in plant involves the uptake and accumulation efficiency, and N use efficiency for grain production. Understanding the mechanisms regulating these processes is crucial for the improvement of NUE in crops. Therefore, is essential to comprehend plants response to different N regimes, mainly N limitation. The usage of plants or varieties with differences in nutrient use efficiency is another important factor to determine the main mechanisms involved in these processes. The objectives of this study were to evaluate N metabolism and expression of genes involved in N uptake and assimilitation of two rice varieties (Piau? and IAC-47), under different N supply conditions. The N metabolism was evaluated by quantification of nitrogen fractions in plant tissue and enzymatic activity, expression of genes that code for high and low affinity N transporters, and N assimilation enzymes. Two experiments were conducted: the first, to investigate the plants behavior when grown under high and low N supply; and the second to verify plants response to NO3 - resupply. The IAC-47 variety showed greatest mass accumulation in all treatments. When plants were grown for a long period under low N supply it was observed a higher nitrate (NO3 -) content in the tissue of Piau? variety, which is adapted to low fertility conditions, as well as a high activity of nitrate reductase and glutamine synthetase in the roots of these plants. When under high NO3 - supply for a long period, Piau? variety had higher NO3 - concentrations in roots and sheaths, but no differences were observed in enzymes activity. The nitrate transporters expression was higher in roots of Piau? plants under low supply of NO3 - when compared to Piau? plants under high N supply. Nitrate transporters expression in roots of IAC-47 plants showed a pattern opposite to the one observed for Piau? plants. When plants were resupplied with NO3 -, after a 72 hours period without N, there was a rapid increase, after 6 hours of resupply, in the expression of high affinity nitrate transporters genes (OsNRT2.1) and the plastidial glutamine synthetase (GS2) in the Piau? variety roots, and a higher expression of these in IAC-47 roots after a 24 hours of N resupply. The efficiency of Piau? variety is related to the differentiated control of N absorption and assimilation mechanisms, which allow bigger expression of high affinity nitrate transporters in tissue with high levels of soluble N, high N status, indicating that the control of nitrogen uptake system may be essential for the nitrogen usage efficient.
O nitrog?nio ? um dos elementos minerais que mais limita o desenvolvimento das plantas. Assim, aumentar a efici?ncia de uso de nitrog?nio (EUN) ? um fator ? essencial para uma agricultura sustent?vel, levando a um aumento da produ??o de alimentos com menor uso de insumos e menos impactos ao ambiente. A EUN envolve a efici?ncia de absor??o e ac?mulo e a efici?ncia de utiliza??o de N para produ??o. Compreender os mecanismos envolvidos nesses processos e como eles s?o controlados ? fundamental para a melhoria da EUN nas plantas cultivadas. Para isso, ? essencial entender a resposta e comportamento das plantas a diferentes regimes de N, principalmente ? limita??o de N. O uso de plantas ou variedades com diferen?as na EUN ? outro fator importante para verificar os principais mecanismos envolvidos. Este trabalho teve por objetivo desse trabalho foi verificar o metabolismo e a express?o de genes envolvidos na absor??o e assimila??o de nitrog?nio nas variedades de arroz Piau? e IAC-47 sob diferentes condi??es de disponibilidade desse nutriente. O metabolismo de N foi avaliado atrav?s da quantifica??o das fra??es nitrogenadas no tecido e atividade enzim?tica, a express?o de genes que codificam para transportadores de N de alta e baixa afinidade e enzimas de assimila??o de N. Foram realizados dois experimentos: o primeiro para verificar o comportamento das plantas quando cultivadas sob alto e baixo suprimento de N; e o segundo, para verificar as repostas ao ressuprimento de N. O ac?mulo de massa foi maior na variedade IAC-47 em todos os tratamentos. Quando as plantas foram cultivadas por um longo per?odo sob baixo suprimento de N foi observado maior teor de nitrato (NO3 -) no tecido da variedade Piau?, adaptada a condi??es de baixa fertilidade, assim como uma alta atividade da nitrato redutase e glutamina sintetase nas ra?zes dessas plantas. Sob alto suprimento de NO3 -, por um longo per?odo, a variedade Piau? apresentou maiores teores de NO3 - nas bainhas e ra?zes, mas n?o foram observas diferen?as na atividade de enzimas. A express?o dos transportadores de nitrato na variedade Piau? foi mais elevada nas ra?zes das plantas sob baixo suprimento de NO3 - quando comparado as plantas sob alto suprimento de N. Na variedade IAC-47 a express?o dos transportadores de NO3 - teve comportamento oposto ao observado para a Piau?. Quando as plantas receberam NO3 -, ap?s um per?odo de 72 horas sem N, houve um r?pido aumento, ap?s 6 horas do ressuprimento, na express?o do gene que codifica para o transportador de NO3 - de alta afinidade OsNRT2.1 e glutamina sintetase plastidial (GS2) nas ra?zes da variedade Piau?, e 24 horas ap?s o ressuprimento a express?o foi maior na variedade IAC-47. A efici?ncia da variedade Piau? esta relacionada ao controle diferenciado dos mecanismos de absor??o e assimila??o de N, que permite a maior express?o dos transportadores de nitrato de alta afinidade em tecido com altos teores de N sol?vel, alto status de N, indicando que o controle do sistema de absor??o de N pode ser essencial para a efici?ncia no uso de nitrog?nio.
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Kariyawasam, Bowithanthri Kalani. "Nouvelles métalloenzymes artificielles obtenues par couplage covalent de complexes métalliques dans une protéine naturelle (Xylanase A) et dans des protéines artificielles (αReps) Functionalized Artificial Bidomain Proteins Based on an α‑Solenoid Protein Repeat Scaffold: A New Class of Artificial Diels−Alderases Recent advances in the field of artificial hemoproteins: New efficient eco-compatible biocatalysts for nitrene-, oxene- and carbene-transfer reactions Artificial iron hydrogenase made by covalent grafting of Knölker’s complex into xylanase: Application in asymmetric hydrogenation of an aryl ketone in water A new artificial hemoprotein with inducible peroxidase- and monooxygenase-like activities". Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS518.
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Dans un contexte de développement durable, les enzymes sont des outils biologiques puissants pour catalyser des réactions avec de très grandes efficacités et spécificités. Inspirée des enzymes et de la catalyse organométallique, l’élaboration de métalloenzymes artificielles émerge depuis plusieurs années comme une stratégie de choix pour fournir aux chimistes de nouveaux biocatalyseurs, en accord avec les principes de la chimie verte. Elles sont construites par l’insertion par interactions supramoléculaires ou couplage covalent, d’un ion ou d’un complexe métallique au sein d’une protéine, qui leur apporte un environnement hydrophobe protecteur et chiral. Lors de cette thèse, plusieurs métalloenzymes artificielles ont été construites par couplage covalent de complexes métalliques dans deux protéines hôtes, qui sont la Xylanase A (Xln) et les protéines artificielles de la famille des Reps. Dans un premier temps, une hydrogénase artificielle a été construite dans le mutant XlnS212C par ancrage covalent d’un complexe de fer appelé complexe de Knölker. L’hydrogénase artificielle obtenue, XlnS212CK, s’est avérée capable de catalyser l’hydrogénation par transfert d’hydrure de la trifluoroacétophénone, TFAC, sans excès énantiomérique. Dans un second temps, quatre Diels-Alderases artificielles ont été construites à partir de la protéine bidomaine (A3_A3’) de la famille des αReps. Les deux meilleures Diels-Alderases, qui ont conduit respectivement au meilleur rendement et la meilleure énantiosélectivité dans la réaction de l’azachalcone sur le cyclopentadiène, ont été élaborées respectivement par fixation covalente de complexe de cuivre de ligands phénanthroline et terpyridine dans un mutant F119C de A3_A3’ : (A3_A3’)F119Phen-Cu(II) et (A3_A3’)F119Terpy-Cu(II). Finalement, une nouvelle hémoprotéine artificielle a été construite par couplage covalent de la méso-tétraphénylporphyrine de manganèse Mn(III)TPP-NHMal dans le mutant (A3_A3’)Y26C. L’hémoprotéine artificielle formée BH MnTPP seule ne montre aucune activité catalytique pour l’oxydation de co-substrats par H2O2. Cependant, de manière inattendue, l’addition d’imidazole et d’une autre protéine αRep, bA3-2, qui se fixe de manière spécifique sur A3_A3 et provoque son ouverture, permet non seulement de déclencher l’activité peroxydase de BH MnTPP, mais également une activité monooxygénase qui catalyse la sulfoxydation du thioanisole par H2O2. Il s’agit du premier exemple décrit à ce jour de métalloenzyme artificielle dont l’activité peut être induite par la fixation d’une protéine partenaireIn a context of sustainable development, enzymes are powerful biological tools to catalyze reactions with very high efficiencies and specificities. Inspired by enzymes and organometallic catalysis, the development of artificial metalloenzymes has emerged for several years as a strategy of choice to provide the chemists with new biocatalysts, in accordance with the principles of green chemistry. They are constructed by the insertion by supramolecular interactions or covalent coupling of an ion or a metal complex within a protein, which provides them with a protective and chiral hydrophobic environment. In this thesis, several artificial metalloenzymes were constructed by covalent coupling of metal complexes into two host proteins, Xylanase A (Xln) and artificial proteins of the Reps family. Initially, an artificial hydrogenase was constructed in the XlnS212C mutant by covalent anchoring of an iron complex known as the Knölker complex. The artificial hydrogenase obtained, XlnS212CK, was found to be capable of catalyzing hydride hydrogenation of trifluoroacetophenone, TFAC, without enantiomeric excess. In a second time, four artificial Diel-Alderases were constructed from the bidomain protein (A3_A3') of the αReps family. The two best Diels-Alderases which led respectively to the best yield and the best enantioselectivity in the reaction of azachalcone on cyclopentadiene were developed respectively by covalent attachment of copper complex of phenanthroline and terpyridine ligands in a mutant F119C of A3_A3' (A3_A3')F119Phen-Cu (II) and (A3_A3')F119 Terpy-Cu (II). Finally, a new artificial hemoprotein was constructed by covalent coupling of the manganese meso-tetraphenylporphyrin Mn(III)TPP-NHMal in the (A3_A3')Y26C mutant. The artificial hemoprotein formed BH-MnTPP alone shows no catalytic activity for the oxidation of co-substrates by H2O2. However, unexpectedly, the addition of imidazole and another αRep protein, bA3-2, which binds specifically to A3_A3’ and causes it to be opened, not only triggers the BH-MnTPP peroxidase activity but also a monooxygenase activity which catalyzes the sulfoxidation of thioanisole by H2O2. This is the first example described to date of artificial metalloenzyme whose activity can be induced by the attachment of a partner protein
Книги з теми "Nitrate use efficiency"
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Australian Soil Fertility Manual. CSIRO Publishing, 2006. http://dx.doi.org/10.1071/9780643100725.
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The Australian Soil Fertility Manual is a trusted guide to the safe use and handling of fertilizers. It describes the types of agricultural soils, how they are classified and the interaction of soil, water and nutrients. It also provides an insight into how plants utilise nutrients and the role that individual nutrients play in the process of plant growth.
This edition has been revised to reflect an increased emphasis on the environmental fate of nutrients and appropriate management strategies. It also has additional information on soil physical, chemical, and biological properties and discussions on the use of lime, dolomite and gypsum.
New content covers liming effectiveness, nitrogen water use efficiency, regulations for handling and using fertilizers, storage and transport of security sensitive ammonium nitrate, budgeting for profitable nitrogen use and best management practice for nitrogen and phosphorus fertilizers. The chapters on potassium; calcium, magnesium and sulfur; plant nutrients and the environment; and heavy metal in fertilizers and agriculture have all been extensively revised and rewritten.
This important work will be an essential text for fertilizer dealers, extension workers, consultants, teachers, farmers, horticulturists, graziers and others concerned with the profitable and environmentally safe use of plant nutrients.
Частини книг з теми "Nitrate use efficiency"
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Singh, Ishwar, Krishan Kumar, Prabha Singh, Pranjal Yadava, and Sujay Rakshit. "Physiological and molecular interventions for improving nitrogen-use efficiency in maize." In Molecular breeding in wheat, maize and sorghum: strategies for improving abiotic stress tolerance and yield, 325–39. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789245431.0019.
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Abstract This chapter discusses (i) the importance of nitrogen in plant growth and development, (ii) what is nitrogen-use efficiency (NUE) and how to manage it, (iii) traits influencing nitrogen-uptake efficiency including root system architecture, root nitrogen transporter system, and interaction with microorganisms, (iv) traits influencing nitrogen-utilization efficiency, such as nitrate assimilation, canopy photosynthesis per unit of nitrogen, (v) identification and use of quantitative trait loci (QTLs) related to NUE, (vi) identification of nitrogen-responsive genes, and (vii) nitrogen signalling and transduction for improving NUE. Intensive research on molecular and genetic aspects of NUE has led to the identification of many new genes, QTLs and alleles that could be deployed to develop new genotypes. The future direction of the research efforts should be towards understanding the interaction of NUE-related genes with cellular small RNA flux and perturbing the system performance through metabolic engineering and genome editing techniques.
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Yadav, Divyansh, and Seema Nara. "Nanozymes for Neurodegenerative Diseases." In Proceedings of the Conference BioSangam 2022: Emerging Trends in Biotechnology (BIOSANGAM 2022), 77–95. Dordrecht: Atlantis Press International BV, 2022. http://dx.doi.org/10.2991/978-94-6463-020-6_9.
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AbstractNeurodegenerative diseases are incurable diseases that get worse as time passes. These diseases are very heterogeneous in nature but have common characteristics like abnormal deposition of protein, glycation, inflammation in particular areas of the brain, and progressive neuronal loss due to oxidative stress. Among these, oxidative stress alone causes a high level of degeneration of neurons. To reduce oxidative stress, natural antioxidants are used but they have some drawbacks like instability, high cost and low reusability. To overcome this, nanozymes are introduced and we have emphasized on major nanozymes whose antioxidant capability has been proven which are gold nanozymes, fullerene, nanoceria, and quantum dots. Gold nanoparticles and their conjugates with other molecules can mimic the enzymatic activity of superoxide dismutase and catalase which decrease the amount of hydrogen peroxide and superoxide radicals in cells. Gold Nanozyme treatment reduces the oxidative stress, nitrite, and sulfhydryl levels in the brain and also rectifies the superoxide dismutase, glutathione, and catalase activity levels. Fullerenols has shown superoxide dismutase activity which was 268 times more effective than mannitol and 37 times more effective than Vitamin E for lipid radicals. Nanoceria has the ability to mimic Superoxide Dismutase as well as catalase activity, can also detoxify peroxynitrite. Quantum dots (QDs) like Graphene Oxide QDs can scavenge the reactive oxygen species and also show indirect activity which alleviates the pathogenesis of the disease. Thus, a nanozyme can be used as an efficient nanomedicine if it is tailored to possess high catalytic activity while eliminating all complications.
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Bharali, Bhagawan, Zafar Ullah, Bhupendra Haloi, Jayashree Chutia, and Sonbeer Chack. "Phytotoxicity of Oxidised and Reduced Nitrogen Aerosols on Potato (Solanum Tuberosum L.) Crop." In Sustainable Potato Production and the Impact of Climate Change, 169–88. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-1715-3.ch008.
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In a field trial (2012), simulated aerosols: NH4Cl (reduced) and NaNO2 (oxidised) @ 10 & 20 kg ha-1y-1 (˜ 100 ppm & ˜ 200 ppm respectively), 1000 cm3m-2 of each along with a control were misted to population of Kufri Jyoti at different growth stages viz., vegetative (10-60 DAS), tuber initiation (60-90 DAS) and tuber bulking >90DAS). The higher dose of aerosols lowered nitrate reductase activity, nitrogen use efficiency, cell membrane stability, tuber yield, but increased photosynthesis, peroxidise activity significantly. The mechanisms of injury in terms of higher peroxidase activity and lower membrane stability of leaf cells have been elucidated. Foliar feeding of nitrogenous pollutant in the form of aerosols to plants at juvenile stage is important in addition to basal use of recommended fertilizers.
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Sharma, R. P., M. K. Jatav, V. K. Dua, and Manoj Kumar. "Nutrient Management for Sustainable Potato Production in India." In Sustainable Potato Production and the Impact of Climate Change, 17–49. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-1715-3.ch002.
Повний текст джерелаАнотація:
Potato is important crop for solving food and nutritional security problem of growing population of India. Application of N in two split dose i.e. half at planting time and rest at time of earthing up produce higher yields and higher N recovery. At the time of planting, calcium ammonium nitrate or ammonium sulphate should be preferred by furrow application. Selection of suitable variety may play major role beside time and method of application in improving nutrient use efficiency. Balanced use of major and micronutrients plays an important role in improving quality of produce besides good yield. Potato based cropping system mostly shows build up of P and negative balance of N and K which may be overcame by organic residues recycling. Intensive cropping system has resulted in wide spread deficiency of secondary and micro nutrients particularly Zn and these must be applied on soil test basis. Integrated nutrient management is a must for an exhaustive and responsive crop like potato.
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Priyadarshi, Soumya Saswat. "Wastewater Treatment Using Microalgae." In Advances in Environmental Engineering and Green Technologies, 338–53. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-4921-6.ch016.
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Six different concentrations of Chlorella vulgaris microalgae culture are incorporated with raw wastewater to improve treatment efficiency in three phases. In phase one of study, 30% and 40% microalgae were incorporated with raw wastewater with 24 hrs retention period for 18 days in a batch mode and these conditions are made same for all phases. During phase two and phase three of study, 20%, 25% and 35%, 45% micro-algae concentrations used to treat raw wastewater respectively. Amongst all the six concentrations, 30% microalgae behaves most efficiently and is able to reduce 34 to 81% COD, 43 to 75% nitrate, and 36 to 99% of phosphorous. Overall ammonia nitrogen reduction varies from 80% to 99%. No attempt was made to control temperature or evaporation losses. These attempts can definitely increase the growth process of microalgae and increase the removal efficiency of nutrients in wastewater.
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Gwebu, Lubelihle, and Canisius Mpala. "Application of Vermifiltration for Domestic Sewage Treatment." In Wastewater Treatment [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.103920.
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Climate change has led to water shortages in semi-arid regions. SDG 13 was advocates for wastewater reuse. Zimbabwe uses centralised conventional sewage treatment systems. Vermifiltration combines filtration process and earthworms in sewage water treatment. Vermifiltration is efficient, viable, requires less expertise and can be decentralised. Vermifiltration technique was used in treating domestic septic tank sewage water. Design parameters and efficiency were determined and characterised Vermifiltered water parameters were compared against the Environmental Management Agency Statutory Instrument 6 irrigation water standards. Vermifilter media contained gravel and composted soil with 20g Eseinia fetida earthworms per litre of soil. Treatments were septic tank raw water, vermifilter and control biofilter. A duplicate analysis was conducted. Hydraulic retention time was 1 hour 40 minutes and hydraulic loading rate 163l/m2/hour. Disposed wastewater did not meet required EMA standards. Both filters were effective in treating domestic sewage. There was a significant difference between untreated and treated wastewater. Vermifilter and the control, significantly (p < 0.01) treated pH, turbidity, total dissolved solids total suspended solids, biological oxygen demand, nitrates, phosphates and total coliforms properties. Vermifiltered water met EMA standards for irrigation and non-potable water uses. Phytoremediation can be incorporated in the designs to increase efficiency.
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Glendining, Margaret J., and Jo U. Smith. "Using a Rotational Modelling System to Explore the Effect of Straw Incorporation on the Efficiency of Nitrogen Use." In Managing Risks of Nitrates to Humans and the Environment, 58–64. Elsevier, 1999. http://dx.doi.org/10.1533/9781845693206.58.
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Elmelouky, Abderrahmane, Abdelhadi Mortadi, Elghaouti Chahid, and Reddad Elmoznine. "Experimental and Theoretical Study of the Adsorption Behavior of Nitrate Ions by Layered Double Hydroxide Using Impedance Spectroscopy." In Electrochemical Impedance Spectroscopy. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.90883.
Повний текст джерелаАнотація:
This chapter analyzes the experimental data using impedance spectroscopy to reduce water pollution by nitrate ions. The adsorption is through a synthesized layered double hydroxide (Zn3-Al-Cl-LDH). The kinetic study data analysis by pseudo-first-order and pseudo-second-order models is highly correlated they were found to fit very well the pseudo-second-order. This is confirmed by fast kinetic modeling of experimental data according to the pseudo-second-order. Furthermore, the Nyquist plots suggest that the grains and grain boundaries have contributed to the conduction mechanism of the material at different adsorption times and monitoring of the adsorption phenomenon. The investigation by impedance spectroscopy was used for modeling by an equivalent circuit. The real and imaginary functions of impedance complex are analyzed by modifying Cole-Cole relaxation. Revel most changes in the structure of the manifestation of the grains and the grains boundaries. The alternative current (AC) conductivity was investigated using the double power law of Jonscher. More importantly, the calculated value and the percentage of efficiency are evaluated in the adsorption. The water molecules and nitrate ions in the adsorbed were favored for the generation of the electrical response. The electrochemical impedance spectroscopy data are often interpreted by using electrical equivalent circuits.
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Ren, Y., A. Das, C. Hessin, and M. Desage-El Murr. "2.4 Redox-Active Ligands in Catalysis for Single-Electron-Transfer Processes." In Free Radicals: Fundamentals and Applications in Organic Synthesis 2. Stuttgart: Georg Thieme Verlag KG, 2021. http://dx.doi.org/10.1055/sos-sd-233-00066.
Повний текст джерелаАнотація:
AbstractRedox-active ligands are well known for their ability to stabilize electronic density on their scaffolds, and coordination complexes with such ligands are often stable, open-shell species. This property can be used as a means to favor single-electron transfer (SET) with external sources and devise catalytic radical manifolds. This chapter highlights selected representative reactions resulting in efficient and broad-scope catalytic methodologies. It covers nitrene and carbene radical reactivity, as well as radical trifluoromethylation.
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Taber, Douglass F. "C–H Functionalization." In Organic Synthesis. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780190200794.003.0019.
Повний текст джерелаАнотація:
Masayuki Inoue of the University of Tokyo oxidized (Tetrahedron Lett. 2011, 52, 4654) the alkyl benzene 1 to the nitrate 2, which could be carried on to the amide 5, the nitrile 6, the alcohol 7, or the azide 8. X. Peter Zhang of the University of South Florida developed (Chem. Sci. 2012, 2, 2361) a Co catalyst for the cyclization of 7 to 8. Justin Du Bois of Stanford University reported (J. Am. Chem. Soc. 2011, 133, 17207) the oxidative cyclization of the sulfamate corresponding to 7 using a Ru catalyst. Seongmin Lee of the University of Texas showed (Org. Lett. 2011, 13, 4766) that the oxidative cyclization of 9 gave the amine 10 with high diastereoselectivity. Fabrizio Fabris of the Università di Venezia used (Tetrahedron Lett. 2011, 52, 4478) a Ru catalyst to oxidize 11 to the ketone 12. Ying-Yeung Yeung of the National University of Singapore found (Org. Lett. 2011, 13, 4308) that hypervalent iodine was sufficient to oxidize 13 to the ketone 14. Huanfeng Jiang of the South China University of Technology methoxycarbonylated (Chem. Commun. 2011, 47, 12224) 15 under Pd catalysis to give 16. Professor Inoue found (Org. Lett. 2011, 13, 5928) that the oxidative cyanation of 17 proceeded with high diastereoselectivity to give 18. Mamoru Tobisu and Naoto Chatani of Osaka University activated (J. Am. Chem. Soc. 2011, 133, 12984) 19 with a Pd catalyst to enable coupling with 20 to give 21. Rh-mediated intramolecular insertion is well known to proceed efficiently into secondary and tertiary C–H bonds. A. Srikrishna of the Indian Institute of Science, Bangalore found (Synlett 2011, 2343) that insertion into the methyl C–H of 22 also worked smoothly to deliver 23. The macrocyclic oligopeptide valinomycin 24 has nine isopropyl groups. It is remarkable, as observed (Org. Lett. 2011, 13, 5096) by Cosimo Annese of the Università di Bari and Paul G. Williard of Brown University, that direct oxidation of 24 with methyl(trifluoromethyl) dioxirane in acetone specifically hydroxylated at 8 (45.5%, our numbering), 7 (28.5%), and 6 (26%).
Тези доповідей конференцій з теми "Nitrate use efficiency"
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Baker, James L., Daniel E. Ressler, Robert Horton, and Thomas C. Kaspar. "New Nitrogen Application/Placement Techniques to Increase Use-Efficiency and Reduce Nitrate Leaching." In Proceedings of the 10th Annual Integrated Crop Management Conference. Iowa State University, Digital Press, 1998. http://dx.doi.org/10.31274/icm-180809-614.
Повний текст джерела
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Sigua, G. C., K. C. Stone, P. J. Bauer, and A. S. Szogi. "Nitrate leaching, water-use efficiency and yield of corn with different irrigation and nitrogen management systems in coastal plains, USA." In ENVIRONMENTAL IMPACT 2016. Southampton UK: WIT Press, 2016. http://dx.doi.org/10.2495/eid160151.
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Kruizenga, Alan, David Gill, and Marianne LaFord. "Corrosion of Austenitic Alloys in Binary 60/40 Nitrate Salt at 600°C." In ASME 2013 7th International Conference on Energy Sustainability collocated with the ASME 2013 Heat Transfer Summer Conference and the ASME 2013 11th International Conference on Fuel Cell Science, Engineering and Technology. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/es2013-18057.
Повний текст джерелаАнотація:
Industrial power utilities are using molten binary nitrate salt as a heat transfer fluid and thermal storage media for solar energy generation. Currently, the maximum bulk temperature is 565°C, due to concerns of salt degradation and materials compatibility with containment vessels. To increase overall cycle efficiency, one must increase the upper temperature of the nitrate salt, thereby lowering the levelized cost of electricity (LCoE) through higher power cycle efficiency. The corrosion performance of 316 stainless steel and Inconel 625 is currently characterized at 600°C. However, the 316SS has exhibited stress corrosion cracking (thought due to aqueous flush in Solar Two [1]), and while In625 performs well, its cost is prohibitive. Therefore, current research seeks to evaluate heat-resistant austenitic alloys for use with nitrate salts, ascertaining if they have superior performance characteristics, as well as assessing their mechanisms of corrosion. Sandia National Laboratory is researching four alloys (S35140, ATI332Mo, RA330, and HA556) for corrosion performance at 600°C for 3000 hours, under a cover gas of air. Air is used to simulate the chemistry conditions expected in a power plant. This work details the corrosion rate and the oxide structure for each alloy. Research indicates all alloys are very corrosion-resistant, with metal loss rates projected to be less than 21μm/year after 3000 hours. Though all alloys performed well, corrosion rate data for RA330 (Fe-19Cr-35Ni + minor elements) currently appears to exhibit a linear loss mechanism. In conclusion, this paper will explore the differences in oxide formation between these similar alloys.
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Galkina, O. V., and A. L. Tarasov. "Efficiency application of mineral fertilizers with biologics in the cultivation of winter wheat in the conditions of the upper Volga region." In Растениеводство и луговодство. Тимирязевская сельскохозяйственная академия, 2020. http://dx.doi.org/10.26897/978-5-9675-1762-4-2020-75.
Повний текст джерелаАнотація:
This paper shows the positive dynamics of the use of various biological products in the cultivation of winter wheat against the background of the use of mineral fertilizers and their impact on the yield growth and development of plants. The experiment was laid on the experimental field of the Ivanovo state agricultural Academy. The soil is sod-podzolic medium loamy. Agrochemical analysis of the soil of the experimental site contains 1.9% humus in the soil, 190 mg/kg mobile phosphorus and 180 mg/kg mobile potassium, pH -5.7. The inoculation of winter wheat seeds by biological products Bisoltan and Extrasol was performed on the day of sowing. Mineral fertilizers in the form of ammonium nitrate, double superphosphate and potassium chloride were applied according to the scheme and applied in the spring before sowing, then cultivation was carried out. According to the research results, it was found that the combined use of biologics and mineral fertilizers allowed to obtain a significant increase in yield, and there was also a positive trend in the development of winter wheat plants.
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Pakzadeh, Behrang, Jay Wos, and Jay Renew. "Flue Gas Desulfurization Wastewater Treatment for Coal-Fired Power Industry." In ASME 2014 Power Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/power2014-32278.
Повний текст джерелаАнотація:
The United States Environmental Protection Agency (USEPA)’s announcement that it will revise the effluent limitation guidelines for steam electric power generating units could affect not only how power plants use water, but also how they discharge it. The revised guidelines may lower discharge limits for various contaminants in flue gas desulfurization (FGD) wastewater including mercury, selenium, arsenic, and nitrate/nitrite. Although the specific details of the guidelines are unknown at present, the power industry is evaluating various technologies that may address the new effluent limitation guidelines and promote water conservation. Moreover, the power industry is looking for avenues to increase water usage efficiency, reuse and recycle throughout its plant processes. Final rule approval is expected by the middle of 2014 and new regulations are expected to be implemented between 2017 and 2022 through 5-year NPDES permit cycles. discharge limits for various contaminants including arsenic, mercury, selenium, and nitrate/nitrite [1]. These pollutant limits may be below the levels achievable today with conventional treatment [2]. A growing interest exists in zero liquid discharge (ZLD) facilities and processes in power plant operations. Potentially stringent discharge limits along with water conservation and reuse efforts are two of the major drivers to achieve ZLD. Potential pollutant levels are so low that ZLD may be the best option, if not an outright requirement [1]. Thermal ZLD systems have been the subject of increased interest and discussion lately. They employ evaporating processes such as ponds, evaporators and crystallizers, or spray dryers to produce a reusable water stream and a solid residue (i.e. waste). Evaporators and crystallizers have been employed in the power industry for a number of years. However, typical A growing interest exists in zero liquid discharge (ZLD) facilities and processes in power plant operations. Potentially stringent discharge limits along with water conservation and reuse efforts are two of the major drivers to achieve ZLD. Potential pollutant levels are so low that ZLD may be the best option, if not an outright requirement. A key disadvantage of thermal ZLD is its high capital cost. One way to reduce this cost is to pre-treat the liquid stream using innovative membrane technologies and reverse osmosis (RO).
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Bradshaw, Robert W., and Nathan P. Siegel. "Molten Nitrate Salt Development for Thermal Energy Storage in Parabolic Trough Solar Power Systems." 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/es2008-54174.
Повний текст джерелаАнотація:
Thermal energy storage can enhance the utility of parabolic trough solar power plants by providing the ability to match electrical output to peak demand periods. An important component of thermal energy storage system optimization is selecting the working fluid used as the storage media and/or heat transfer fluid. Large quantities of the working fluid are required for power plants at the scale of 100-MW, so maximizing heat transfer fluid performance while minimizing material cost is important. This paper reports recent developments of multi-component molten salt formulations consisting of common alkali nitrate and alkaline earth nitrate salts that have advantageous properties for applications as heat transfer fluids in parabolic trough systems. A primary disadvantage of molten salt heat transfer fluids is relatively high freeze-onset temperature compared to organic heat transfer oil. Experimental results are reported for formulations of inorganic molten salt mixtures that display freeze-onset temperatures below 100°C. In addition to phase-change behavior, several properties of these molten salts that significantly affect their suitability as thermal energy storage fluids were evaluated, including chemical stability and viscosity. These alternative molten salts have demonstrated chemical stability in the presence of air up to approximately 500°C in laboratory testing and display chemical equilibrium behavior similar to Solar Salt. The capability to operate at temperatures up to 500°C may allow an increase in maximum temperature operating capability vs. organic fluids in existing trough systems and will enable increased power cycle efficiency. Experimental measurements of viscosity were performed from near the freeze-onset temperature to about 200°C. Viscosities can exceed 100 cP at the lowest temperature but are less than 10 cP in the primary temperature range at which the mixtures would be used in a thermal energy storage system. Quantitative cost figures of constituent salts and blends are not currently available, although, these molten salt mixtures are expected to be inexpensive compared to synthetic organic heat transfer fluids. Experiments are in progress to confirm that the corrosion behavior of readily available alloys is satisfactory for long-term use.
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Usrey, Michael W., Yiping Liu, Mark Anderson, Jon Lubbers, Brady Knowles, Kevin Harsh, and Evan Pilant. "Development of High Temperature, Corrosion Resistant Sensors for Concentrating Solar Power Systems." In ASME 2014 8th International Conference on Energy Sustainability collocated with the ASME 2014 12th International Conference on Fuel Cell Science, Engineering and Technology. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/es2014-6569.
Повний текст джерелаАнотація:
Solar power is a sustainable resource which can reduce the power generated by fossil fuels, lowering greenhouse gas emissions and increasing energy independence. The U.S. Department of Energy’s SunShot Initiative has set goals to increase the efficiency of concentrating solar power (CSP) systems. One SunShot effort to help CSP systems exceed 50% efficiency is to make use of high-temperature heat transfer fluids (HTFs) and thermal energy storage (TES) fluids that can increase the temperature of the power cycle up to 1300°C. Sporian has successfully developed high-temperature operable pressure, temperature, thermal flux, strain, and flow sensors for gas path measurements in high-temperature turbine engines. These sensors are based on a combination of polymer derived ceramic (PDC) sensors, advanced high-temperature packaging, and integrated electronics. The overall objective is the beneficial application of these sensors to CSP systems. Through collaboration with CSP industry stakeholders, Sporian has established a full picture of operational, interface, and usage requirements for trough, tower, and dish CSP architectures. In general, sensors should have accurate measurement, good reliability, reasonable cost, and ease of replacement or repair. Sensors in contact with hot salt HTF and TES fluids will experience temperature cycling on a daily basis, and parts of the system may be drained routinely. Some of the major challenges to high-temperature CSP implementation include molten salt corrosion and flow erosion of the sensors. Potential high-temperature sensor types that have been identified as of interest for CSP HTF/TES applications include temperature, pressure, flow, and level sensors. Candidate solar salts include nitrate, carbonate, and chloride, with different application temperatures ranging from 550°C-900°C. Functional ceramics were soaked for 500 hours in molten nitrate, carbonate, and chloride salts, showing excellent corrosion resistance in chloride salts and good resistance in nitrate salts. The demonstration of functional ceramics in relevant HTFs laid the foundation for full prototype sensor and packaging demonstration. Sporian has developed a packaging approach for ceramic-based sensors in various harsh gaseous environments at temperatures up to 1400°C, but several aspects of that packaging are not compatible with corrosive and electrically conductive HTFs. In addition to consulting published literature, a 300 hour soak test in molten chloride salt allowed the authors to identify suitable structural metals and ceramics. Based on discussions with stakeholders, molten salt corrosion testing and room-temperature water flow testing, suitable for CSP sensor/packaging concepts were identified for future development, and initial prototypes have been built and tested.
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GOLOVKO, Liudmyla. "IMPLEMENTATION OF EU WATER POLICY IN UKRAINE: PROBLEMS AND PERSPECTIVES." In RURAL DEVELOPMENT. Aleksandras Stulginskis University, 2018. http://dx.doi.org/10.15544/rd.2017.103.
Повний текст джерелаАнотація:
The use, protection and management of water resources belong to the most urgent among global environmental problems of our time. Today, the civilization clearly realizes the need for careful management of water resources, maintaining and restoring its quality. Water quality determines the possibility of its use in various fields of human activity. For Ukraine problems of water sector are also acute and urgent. Low efficiency of water use, poor drinking water quality, nitrate contamination of water resources, poor condition of water bodies in Ukraine require more foreign experience in this sphere, especially the EU experience. The purpose of our scholarly work is to explore actual problems of harmonization of water legislation of Ukraine with the requirements of EU water policy and development of proposals for the improvement of Ukrainian legislation. Main features of harmonization of Ukrainian legislation in the water resources management sphere with EU law and prospects for implementation of principles of EU Water Framework Directive were analyzed. As a result of the study the ways of implementation of positive foreign experience of water objects management in Ukraine are considered. Considering the scale of ecological crisis in Ukraine the necessity of forming a new system of economic regulators of nature is obvious. Such system must not only accumulate funds for urgent actions, but primarily encourage economic entities to protect the natural environment. We consider it appropriate to introduce mandatory environmental insurance for operators of environmentally hazardous activities.
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Gill, David D., Nathan P. Siegel, Robert W. Bradshaw, and Clifford K. Ho. "Design, Fabrication and Testing of an Apparatus for Material Compatibility Testing in Nitrate Salts at Temperatures Up to 700°C." In ASME 2011 5th International Conference on Energy Sustainability. ASMEDC, 2011. http://dx.doi.org/10.1115/es2011-54250.
Повний текст джерелаАнотація:
Thermal energy storage is one of the key differentiators between Concentrating Solar Power (CSP) and other renewable energy technologies. Molten salt is an effective and affordable method of storing thermal energy. Current salt storage systems charge at temperatures between 390°C and 585°C (oil filled parabolic trough systems to molten salt towers). It is highly desirable to increase the operating temperature of salt storage systems in order to increase the efficiency of the power cycle and to permit the use of alternative, high-temperature cycles. However, higher salt temperatures cause increased reactivity and thus increased corrosion rates in many materials. In order to utilize molten salt at higher temperature, it is necessary to test and understand these corrosion interactions at elevated temperature. A corrosion test system has been designed and built for evaluating molten salt/material interactions to 700°C. The primary components of this system are several salt containment vessels that are constructed of 6″ dia. × 24″ long stainless steel, aluminum diffusion treated pipes with flat plate welded to one end and a flanged lid on the other. The vessels are designed to operate with a charge of 10 kg of molten salt and accommodate a “sample tree” on which corrosion test coupons may be suspended. The salt vessels are heated and insulated on the bottom half, roughly to the salt fill level, and cooled on the top half to protect the flange gasket and feedthrough ports. The samples trees have a stainless plate that reduces radiative heat transfer from the molten salt to the lid. Finite element analysis was performed to determine the pipe length and heating and cooling requirements to maintain molten salt at 700°C while limiting the lid gasket to 300°C or less. The vessels are designed to have an oxygen atmosphere in the ullage region to mitigate nitrate decomposition. Oxygen systems for operation at 700°C require careful design including the sizing, routing, cleanliness, and material selection of components in order to reduce risk of fire. Additionally, the system is designed to run at 1–2 psig which requires specialized low pressure / high temperature components. In this paper we present the design of the molten salt corrosion test system including details related to the containment vessels, oxygen handling system, and control software along with a discussion of the safety considerations necessary for these high temperature, high oxygen partial pressure tests.
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Kelly, Bruce, Henry Price, Doug Brosseau, and David Kearney. "Adopting Nitrate/Nitrite Salt Mixtures as the Heat Transport Fluid in Parabolic Trough Power Plants." In ASME 2007 Energy Sustainability Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/es2007-36172.
Повний текст джерелаАнотація:
The present generation of commercial parabolic trough solar power plant uses a synthetic oil as the heat transport fluid in the collector field. The plants are currently operating at the upper temperature limit of the fluid, and further improvements in the solar-to-electric conversion efficiency are likely to be incremental. In contrast, adoption of a nitrate salt, or a nitrate/nitrite salt, mixture as the heat transport fluid would allow the collector field outlet temperature to increase by 50 to 100 °C, which translates into an increase in the gross Rankine cycle efficiency from the present 37.5 percent to new values in the range of 40 to 41 percent. Further, the low cost and the low vapor pressure of the candidate salt mixtures allow the heat transport fluid to also act as the storage medium in a thermal storage system. Using a salt mixture in the collector field should reduce the unit cost of thermal storage by approximately half compared to the current indirect designs. The principal, and far from minor, liability of the candidate salt mixtures are freezing points in the range of 120 °C to 220 °C. As a consequence, all salt components, including the collector field, will require some form of electric heating for freeze protection. Further, collector designs will need to be demonstrated, or developed, which are tolerant of a limited number of freeze/thaw cycles. The candidate salts are also corrosive to the current ball joint sealing materials. This paper outlines the problems which need to be solved before a commercial salt project could reasonably be considered by a project developer, the elements of a test and demonstration program to solve the problems, and the contributions which will be necessary from the salt component vendors, the project developers, and the financial community.
Звіти організацій з теми "Nitrate use efficiency"
1
Van Rijn, Jaap, Harold Schreier, and Yossi Tal. Anaerobic ammonia oxidation as a novel approach for water treatment in marine and freshwater aquaculture recirculating systems. United States Department of Agriculture, December 2006. http://dx.doi.org/10.32747/2006.7696511.bard.
Повний текст джерелаАнотація:
Ammonia waste removal in recirculating aquaculture systems is typically accomplished via the action of nitrifying bacteria in specially designed biofilters that oxidize ammonia to produce nitrate. In the majority of these systems nitrate is discharged to the environment through frequent water exchanges. As environmental considerations have made it necessary to eliminate nitrate release, new strategies for nitrate consumption are being developed. In the funding period we showed that ammonia removal from wastewater could take place by an anaerobic ammonia oxidation process carried out by bacterial Planctomycetessp. Referred to as “anammox”, this process occurs in the absence of an organic source and in the presence of nitrite (or nitrate) as an electron acceptor as follows: NH₃ + HNO₂ -> N₂ + 2H₂O. Annamox has been estimated to result in savings of up to 90% of the costs associated with was wastewater treatment plants. Our objective was to study the applicability of the anammox process in a variety of recirculating aquaculture systems to determine optimal conditions necessary for efficient ammonia waste removal. Both seawater and freshwater systems operated with either conventional aerobic treatment of ammonia to nitrate (USA) or, in addition, denitrifying biofilters as well as anaerobic digestion of sludge (Israel) were tested. Molecular tools were used to screen and monitor different treatment compartments for the presence of Planctomycetes. Optimal conditions for the enrichment of the anammox bacteria were tested using laboratory scale biofilters as well as a semi-commercial system. Enrichment studies resulted in the isolation of some unique heterotrophic bacteria capable of plasmid-mediated autotrophic growth in the presence of ammonia and nitrite. Our studies have not only demonstrated the presence and viability of Planctomycetes spp. in recirculating marine and freshwater systems biofilter units but also demonstrated the applicability of the anammox process in these systems. Using our results we have developed treatment schemes that have allowed for optimizing the anammox process and applying it to recirculating systems.