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Effects of Nitrogen Treatments on Organic Carbon Mineralization of Citrus Orchard Soil 被引量:2
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作者 翁伯琦 王峰 +4 位作者 王义祥 江福英 吴志丹 尤志明 张文锦 《Agricultural Science & Technology》 CAS 2012年第8期1702-1707,共6页
[Objective] This study aimed to investigate the effect of soil organic carbon mineralization at different temperature on the amount of nitrogen application, in order to provide references for the establishment of carb... [Objective] This study aimed to investigate the effect of soil organic carbon mineralization at different temperature on the amount of nitrogen application, in order to provide references for the establishment of carbon circulation model for orchard eco-system. [Method] The effects of nitrogen treatments on soil organic carbon mineralization of citrus orchard soil were investigated under 10, 20, 30 ℃ by laboratory simulated experiment. [Result] The mineralization rate decreased quickly at the be- ginning of the experiment but remained stable at the late period under three temper- ature treatments. The amounts of CO2 ranged from 1 328.25-2 219.42 mg/kg under three temperature condition, and the amount of soil organic carbon mineralization of 100 mg/kg (N4) treatment was the greatest, while that of CK was the lowest. High level nitrogen treatment (N4 and N3) were significant higher than the lower level nitro- gen treatment (N2 and N1). The soil organic carbon mineralization rate increased with the temperature from 10 to 30℃. The dependence of soil carbon mineralization to temperature (Q10) was different under different nitrogen treatments that the Qlo value of N2 treatment was the lowest while that of the N4 treatment was the greatest. The soil organic carbon mineralization in Citrus orange orchard soil was affected significantly by high level nitrogen treatment, but with no significance under lower nitrogen treatment. [Conclusion] The dependence of soil carbon mineralization to temperature (Q10) increased with the increasing nitrogen input. The combination of nitrogen with temperature may increase the CO2 emission from Citrus orchard soil. 展开更多
关键词 Citrus orchard Soil organic carbon mineralization nitrogen treatment TEMPERATURE
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The Influence of Different Nitrogen Treatments on the Growth and Yield of Basil (Ocimum Basificum L.) 被引量:1
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作者 Laura Frabboni Giuseppina de Simone Vittoria Russo 《Journal of Chemistry and Chemical Engineering》 2011年第9期799-803,共5页
Sweet basil (Ocimum basilicum L.) is a popular culinary herbal crop grown for the fresh or dry leaf, essential oil and seed markets. Recently, basil has been shown to rank highest among spices and herbal crops for x... Sweet basil (Ocimum basilicum L.) is a popular culinary herbal crop grown for the fresh or dry leaf, essential oil and seed markets. Recently, basil has been shown to rank highest among spices and herbal crops for xanthophyll carotenoids, which are associated with a decreased risk of cancer and age-related eye diseases. Nitrogen fertilizer encourages vegetative growth and increases oil yield in aromatic plants by enhancing leaf area development and photosynthetic rate. Our goal was to determine the influence of different concentrations of nitrogen (N) fertilization on basil physiology. The trial examined the cultivation of Ocimum basilicum L. (variety Genovese gigante). The experiment was carried out under Mediterranean climatic conditions. The experiment considered the adoption of three nitrogen (N) treatments (0, 160, 240 kg N ha-1). The following biometric parameters were determined: plant height, leaves per plant, leaf to stem ratio, number of branchings per plant, leaf area index (LAI), above-ground fresh and leaf biomass. Considering the parameters most strictly linked to the economic results (total fresh weight, fresh weight of the leaves and total dry weight), we found that 160 kg N ha^-1 treatment showed the best performance. 展开更多
关键词 nitrogen treatment BASIL YIELD yield components growth Ocimum basilicum L.
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Prediction and Analysis of Total Nitrogen in a Sewage Treatment Plant Effluent
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作者 Kemeng Xue 《Open Journal of Modelling and Simulation》 2024年第4期114-129,共16页
Total nitrogen was an important indicator for characterizing eutrophication of polluted water. Although the use of water quality online monitoring instrument can monitor water quality changes in real time, the degree ... Total nitrogen was an important indicator for characterizing eutrophication of polluted water. Although the use of water quality online monitoring instrument can monitor water quality changes in real time, the degree of intelligence was low, so it was urgent to predict the water quality and take precautions in advance. A predictive model for total nitrogen levels in a sewage treatment plant utilizing the Anaerobic-Anoxic-Oxic (AAO) process was investigated in this paper. This model demonstrated significant practical application value. Based on the ARIMA (Autoregressive Integrated Moving Average) model and taking into account the impact of Biochemical Oxygen Demand (BOD), a prediction model for effluent total nitrogen was developed. However, the initial results exhibited significant deviations. To address this issue, seasonal factors were further considered. Then, the dataset was divided into winter and Non-winter sub-samples, leading to a reconstruction of the prediction model. Additionally, in developing the Non-winter prediction model, life cycle considerations were incorporated, and consequently, a SARIMA (Seasonal Autoregressive Integrated Moving Average) model was established. The predicting deviation associated with both the winter and Non-winter forecasting models showed a significant reduction. 展开更多
关键词 Total nitrogen Sewage treatment Plant PREDICTION ARIMA Model
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Effect of Nitrogenous Fertilizer Treatment on Mineral Metabolism in Grazing Yaks 被引量:3
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作者 SHEN Xiao-yun 《Agricultural Sciences in China》 CAS CSCD 2009年第3期361-368,共8页
To assess the impact of N fertilization on contents of mineral elements in herbage and the effect of increased forage S on the copper metabolism of grazing yaks, study was conducted during the summer grazing season (... To assess the impact of N fertilization on contents of mineral elements in herbage and the effect of increased forage S on the copper metabolism of grazing yaks, study was conducted during the summer grazing season (2005, 2006, and 2007). Pasture replicates (20 ha; n=3 per treatment) received the same fertilizer treatment in each growing season, consisting of i) 90 kg N ha^-1 from quickly available nitrogen, ii) 90 kg N ha^-1 from ammonium nitrate, iii) 90 kg N ha^-1 from ammonium sulfate, and iv) control (no fertilizer). Forage sampling was collected at 60 days intervals following fertilization (10 samples per pasture) for Cu, Mo, Mn, Se, Fe, Zn, Ca, and P. To determine the effect of fertilizer treatment on mineral metabolism in grazing yaks, liver and blood samples were collected at the start and end of the study period in 2005, 2006, and 2007. Ammonium sulfate fertilization increased (P 〈 0.01) forage S concentration. Plant tissue N concentrations were increased by N fertilization, regardless of source in 2005, 2006, and 2007. Yaks grazing S fertilization pastures had lower (P〈0.05) liver and blood Cu concentrations at the end of the study period in 2005, 2006, and 2007, compared with urea, ammonium nitrate, and control. Nominal increases in forage in vitro organic matter digestibility were realized by fertilization, regardless of N source in each year. 展开更多
关键词 yaks nitrogen fertilizer treatment alpine meadow FORAGE mineral element metabolism
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Effects of heat treatment on the microstructures and mechanical properties of a new type of nitrogen-containing die steel 被引量:7
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作者 Jing-yuan Li Peng Zhao +2 位作者 Jun Yanagimoto Sumio Sugiyama Yu-lai Chen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2012年第6期511-517,共7页
Nitrogen can increase the strength of steels without weakening the toughness and improve the corrosion resistance at the same time. Compared with conventional nitrogen-free die steels, a new type of nitrogen-containin... Nitrogen can increase the strength of steels without weakening the toughness and improve the corrosion resistance at the same time. Compared with conventional nitrogen-free die steels, a new type of nitrogen-containing die steel was developed with many superior properties, such as high strength, high hardness, and good toughness. This paper focused on the effects of heat treatment on the microstruc- tures and mechanical properties of the new type of nitrogen-containing die steel, which were investigated by the optimized deformation process and heat treatment. Isothermal spheroidal annealing and high-temperature quenching as well as high-temperature tempering were ap- plied in the experiment by means of an orthogonal method after the steel was multiply forged. The mechanical properties of nitro- gen-containing die steel forgings are better than the standard of NADCA #207-2003. 展开更多
关键词 die steels nitrogen heat treatment microstructure mechanical properties forgings
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Heat Treatment and Properties of Nitrogen Alloyed, Martensitic, Corrosion-resistant Steels 被引量:3
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作者 Reinhold Schneider Klaus Sammt +1 位作者 Roland Rabitsch Michael Haspel 《材料热处理学报》 EI CAS CSCD 北大核心 2004年第5期582-587,共6页
This paper gives a short introduction to the typical process route and material properties of these steels in comparison to standard martensitic corrosion-resistant steels. The typical response of these steels to vari... This paper gives a short introduction to the typical process route and material properties of these steels in comparison to standard martensitic corrosion-resistant steels. The typical response of these steels to various heat treatment parameters is shown and explained using the three grades M333, N360 and M340 (all made by Bohler Edelstahl GmbH) as examples, and the physical metallurgy of these steels and its consequences for practical heat treatment is explained. The correlation between tempering parameters and their effect on the toughness and corrosion properties is explained in particular detail, showing that these new steels not only offer far better property combinations under the usual heat treatment parameters than standard martensitic corrosion-resistant steels, but that they also open the door to extending heat treatment combinations and properties. 展开更多
关键词 热处理 高氮钢 马氏体钢 抗腐蚀钢
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Nitrogen Plasma Treatment Effect on Graphene Sheeted Vertically Aligned Carbon Nanofibers
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作者 Dilip Chandra Ghimire M. Matsushima M. Umeno 《Journal of Chemistry and Chemical Engineering》 2013年第9期842-846,共5页
Nitrogen plasma treatment effect on GS-CNFs (graphene seeted vertically aligned carbon nanofibers) has been studied. GS-CNFs were grown on nickel coated cupper substrates by DC-plasma CVD (chemical vapor deposition... Nitrogen plasma treatment effect on GS-CNFs (graphene seeted vertically aligned carbon nanofibers) has been studied. GS-CNFs were grown on nickel coated cupper substrates by DC-plasma CVD (chemical vapor deposition) at relatively low temperature. GS-CNFs were studied by SEM (scanning electron microscopy), HR-TEM (high-resolution transmission electron microscopy), XPS and Raman measurements. GS-CNFs are composed of cylindrical shaped having pure graphite sheets with about 5 μm length and nanometer size tips and roots diameter. Nitrogen plasma treatment causes nitrogen chemical etching on the graphene seeted carbon nanofibers were disordered its fine shape and increase the graphetization due to nitrogen incorporation. 展开更多
关键词 DC-plasma CVD graphene seeted carbon nanofibers nitrogen plasma treatment effect.
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Effect of Treatment Temperature on Iron Nitride Foils Irradiated with Nitrogen Plasma 被引量:1
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作者 K.Niizuma and Y. Utsushiforwa (College of Industrial Technology, Nihon University, Narashino, Chiba 275-8575, Japan) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第2期143-144,共2页
We investigated the effect of treatment temperature on the magnetic property of iron nitride foils irradiated with nitrogen plasma. The iron nitride foils irradiated with nitrogen plasma were composed of ε-Fe2/3N, γ... We investigated the effect of treatment temperature on the magnetic property of iron nitride foils irradiated with nitrogen plasma. The iron nitride foils irradiated with nitrogen plasma were composed of ε-Fe2/3N, γ'-Fe4N and γ nitrogen austenite in α-Fe of the matrix. The saturation magnetization of the iron nitride foils decreased with increasing the surface temperature. The coercive force of the iron nitride foils increased with increasing the surface temperature. 展开更多
关键词 Effect of treatment Temperature on Iron Nitride Foils Irradiated with nitrogen Plasma
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Experimental analysis of a nitrogen removal process simulation of wastewater land treatment under three different wheat planting densities 被引量:2
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作者 WangHQ ChenJJ 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第3期317-324,共8页
Nitrogen contaminant transport, transformation and uptake simulation experiments were conducted in green house under three different planting density of winter wheat. They were Group A, planting density of 0.0208 plan... Nitrogen contaminant transport, transformation and uptake simulation experiments were conducted in green house under three different planting density of winter wheat. They were Group A, planting density of 0.0208 plants/cm 2, Group B, 0.1042 plants /cm 2, and Group C, 0.1415 plants/cm 2. The capacity and ratio of nitrogen removal were different on three kinds of conditions of wastewater land treatment. From analysis of wastewater treatment capacity, wastewater concentration and irrigation intensity for Group C were suitable and nitrogen quantity added was 2 times of that for Group B, 2.6 times for Group A while nitrogen residue was only 7.06%. Hence, wastewater irrigation and treatment design with purpose of waste water treatment should select the design with maximum capacity, optimal removal ratio and least residue in soil, which was closely related to crop planting density, crop growth status and also background nitrogen quantity in soil. 展开更多
关键词 wastewater land treatment planting density winter wheat nitrogen removal SOIL
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Traditional Nitrogen Removal Coupled with SND to Meet Advanced WWTP Standards at a Full Scale SBR Wastewater Treatment Facility 被引量:1
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作者 Charlie L. Martin Jr. Clayton J. Clark II 《Journal of Water Resource and Protection》 2017年第10期1169-1183,共15页
A Florida wastewater treatment facility studied how Simultaneous Nitrification Denitrification (SND) coupled with traditional nitrogen removal would be used to meet the state’s current advanced wastewater treatment n... A Florida wastewater treatment facility studied how Simultaneous Nitrification Denitrification (SND) coupled with traditional nitrogen removal would be used to meet the state’s current advanced wastewater treatment nutrient criterion. This study examined the effect of these combined processes on the fate and transport of the nitrogen species during the treatment process. The effectiveness of nitrogen removal within the full scale sequential batch reactor system (SBR) and the extent of SND compared to nitrification and denitrification in the nitrogen removal process was also evaluated. Finally, the overall performance of the municipal wastewater treatment facility utilizing these combined processes was evaluated. Overall, this application reduced the total nitrogen to almost 6% of the permitted concentration of 3.0 mg/L. The combination of both processes also resulted in an actual ?concentration 93.7% lower than the acceptable theoretical ?concentration, which also resulted in effluent Total Inorganic Nitrogen nearly 80% lower than the permitted 3.0 mg/L effluent concentration. Further, the process produced a composite Total Nitrogen concentration that was 74% lower than the permitted concentration. This coupling of SND with traditional nitrogen removal resulted in a highly effective process to reduce nitrogen in the municipal wastewater effluent which is also attractive for potential implementation due to the low cost expenditure incurred in its utilization. 展开更多
关键词 nitrogen Simultaneous NITRIFICATION DENITRIFICATION (SND) Wastewater treatment Full Scale FACILITY
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Nitrogen Removal Efficiency of the Reclaimed Water by Land Treatment System
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作者 LI Jian-min LIU Pei-bin +1 位作者 WEI Wei DONG Zhi-ying 《Meteorological and Environmental Research》 2012年第7期12-14,共3页
[Objective] The research aimed to study nitrogen removal effect of the land treatment process on reclaimed water. [Method] By using land treatment system, reclaimed water which reached one-level A standard was conduct... [Objective] The research aimed to study nitrogen removal effect of the land treatment process on reclaimed water. [Method] By using land treatment system, reclaimed water which reached one-level A standard was conducted advanced processing, and nitrogen removal efficiency of the effluent was inspected. [ Result] There was a positive correlation between organic matter content of the soil medium and nitrogen removal effect. With appropriate soil medium, TN and NH3-N could obtain the removal efficiency of more than 90% and 75% respectively, and they could be removed at 30 and 10 cm height of soil medium respectively with land treatment system to treat reclaimed water. [ Conclusion ] The research provid- ed theoretical basis for application of the land treatment system into nitrogen removal of the reclaimed water. 展开更多
关键词 Land treatment system Reclaimed water nitrogen removal China
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高温和液氮处理对马棘种子萌发能力的影响 被引量:1
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作者 范彦 姜吉顺 +2 位作者 何玮 刘畅 罗燕 《草学》 2024年第1期44-51,共8页
马棘为豆科木兰属多年生小灌木,具有较高的饲用及生态价值,但自然条件下种子的发芽率低,研发提高马棘种子萌发能力的技术措施,将为马棘的推广应用提供重要支撑。本试验以2022年收获的马棘种子为试材,进行不同时间的高温(60℃)、液氮及... 马棘为豆科木兰属多年生小灌木,具有较高的饲用及生态价值,但自然条件下种子的发芽率低,研发提高马棘种子萌发能力的技术措施,将为马棘的推广应用提供重要支撑。本试验以2022年收获的马棘种子为试材,进行不同时间的高温(60℃)、液氮及其组合预处理,并开展发芽实验。其中,液氮和高温分别设计了4个种子处理时间,液氮处理的时间分别为0.5、1、2、5min;高温(60℃)处理的时间分别为10、30、60、180min;组合处理包括先高温后液氮处理及先液氮后高温处理两种方式;试验处理有自然萌发条件下的对照(CK)、8个单一处理及32个组合处理,共计41个。种子发芽周期结束后计算种子发芽率、发芽势、发芽指数及平均萌发时间,并利用隶属函数的方法评价不同处理对马棘种子发芽能力的影响。马棘种子自然条件下发芽率为55%,不同时间高温处理对种子发芽率的提升作用不显著(P>0.05);用液氮处理马棘种子1min后,发芽率可达78.5%,显著高于CK(P<0.05);先高温后液氮组合处理中,高温30min+液氮5min、高温60min+液氮2min两处理发芽率可达80%;先液氮后高温组合处理中,液氮1min+高温60min发芽率最高,可达82.5%,比CK发芽率高27.5%。液氮1min+高温60min处理,能显著提高马棘种子的发芽能力,且该方法处理种子,操作简单,耗时短,生产实用性强,值得推广。 展开更多
关键词 马棘 高温处理 液氮处理 种子萌发
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固定化异养硝化-好氧反硝化菌在污水生物强化中的研究进展
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作者 程海娜 储雪妍 +3 位作者 陈祝 陈辉 周洪波 王玉光 《水处理技术》 CAS CSCD 北大核心 2024年第3期13-19,共7页
异养硝化-好氧反硝化(Heterotrophic nitrification-aerobic denitrification,HN-AD)菌可以在有机碳存在的好氧条件下实现同时硝化和反硝化,广泛应用于各类污水处理过程中。综述了HN-AD菌株的脱氮特性和代谢途径,总结了其在污水处理中... 异养硝化-好氧反硝化(Heterotrophic nitrification-aerobic denitrification,HN-AD)菌可以在有机碳存在的好氧条件下实现同时硝化和反硝化,广泛应用于各类污水处理过程中。综述了HN-AD菌株的脱氮特性和代谢途径,总结了其在污水处理中的应用和研究现状,比较了不同载体材料的优缺点,重点讨论了固定HN-AD菌株提高反应器处理效果和稳定性的作用机理。最后,展望了固定化HN-AD菌株在污水处理中面临的挑战和未来的研究方向。 展开更多
关键词 异养硝化-好氧反硝化 微生物固定化技术 生物脱氮 污水处理
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污水生物处理系统脱氮除磷细菌多样性及功能调控
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作者 蒙小俊 葛光环 +2 位作者 王亚萍 金文婷 肖薇薇 《工业水处理》 CAS CSCD 北大核心 2024年第11期17-26,共10页
污水处理厂生物处理单元的性能决定其对污水脱氮除磷的效率,而脱氮除磷细菌的菌群结构、代谢活性和细菌间的种间协同与竞争是生物处理单元功能发挥的关键。分析了污水生物处理系统脱氮除磷细菌的核心菌群和代谢机制,从物种水平上解析了N... 污水处理厂生物处理单元的性能决定其对污水脱氮除磷的效率,而脱氮除磷细菌的菌群结构、代谢活性和细菌间的种间协同与竞争是生物处理单元功能发挥的关键。分析了污水生物处理系统脱氮除磷细菌的核心菌群和代谢机制,从物种水平上解析了Nitrosomonas、Nitrosospira、Nitrospira、Nitrobacter、Ca. Kuenenia、Ca. Brocadia和Thauera等主要脱氮微生物的生理特性,对除磷微生物Candidatus Accumulibacter、Dechloromonas和Tetrasphaera的生理特性进行了概述;探索了脱氮除磷菌种间协同与种间竞争关系,并从改造工艺结构、优化运行条件和人工强化3个方面对脱氮除磷细菌功能调控进行论述,以期为污水生物处理单元功能调控及污水处理厂升级改造提供理论依据。 展开更多
关键词 污水处理 细菌多样性 脱氮除磷 功能调控
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潜流人工湿地脱氮除磷基质的应用研究及展望
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作者 代学民 王立杰 +4 位作者 南国英 邓大鹏 张斯 张涛 任淑萍 《工业用水与废水》 CAS 2024年第2期1-6,共6页
基质的选择直接影响着潜流人工湿地全生命周期及污水处理效果,不同类型的基质对脱氮除磷具有差异性效果。综述了不同类型潜流人工湿地基质的研究现状,分析了其脱氮除磷机理,总结了各类基质的应用效果,展望了天然矿石基质、固体废弃物基... 基质的选择直接影响着潜流人工湿地全生命周期及污水处理效果,不同类型的基质对脱氮除磷具有差异性效果。综述了不同类型潜流人工湿地基质的研究现状,分析了其脱氮除磷机理,总结了各类基质的应用效果,展望了天然矿石基质、固体废弃物基质和人工合成基质研究方向和研究重点,以期为潜流人工湿地脱氮除磷基质的研发提供参考。 展开更多
关键词 基质 脱氮除磷 污水处理 潜流人工湿地 复合基质 农业废弃物
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常压法硝酸装置的优化改造
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作者 黎志敏 龚赵峰 《化工生产与技术》 CAS 2024年第1期30-32,38,I0004,共5页
以杭州龙山化工的常压法硝酸装置为例,该装置在运行中出现尾气环保达标排放困难和产品结构不合理等问题。通过采取硝酸生产工艺优化和新增尾气处理装置等改造,调整了硝酸和亚硝酸钠产品结构,可减少亚硝酸钠产量2 kt/a,同时增加硝酸(质... 以杭州龙山化工的常压法硝酸装置为例,该装置在运行中出现尾气环保达标排放困难和产品结构不合理等问题。通过采取硝酸生产工艺优化和新增尾气处理装置等改造,调整了硝酸和亚硝酸钠产品结构,可减少亚硝酸钠产量2 kt/a,同时增加硝酸(质量分数为40%)产量4 kt/a;尾气中氮氧化物质量浓度<300 mg/m^(3),解决了尾气达标排放问题。该方法可为同行业类似的常压法硝酸装置改造提供借鉴经验。 展开更多
关键词 常压法硝酸装置 氮氧化物 尾气处理 氨催化还原
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污水硫自养反硝化技术研究进展 被引量:1
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作者 高舒嘉 邵军荣 +2 位作者 成宇 朱宗强 胡承志 《土木与环境工程学报(中英文)》 CSCD 北大核心 2024年第2期227-235,共9页
硫自养反硝化(SAD)是一种绿色低碳的污水脱氮技术,具有成本低、污泥产量少、无须外加有机碳源等优点,已成为污水脱氮技术研究的热点之一。阐述SAD填料组成与复合硫源填料的合成方法,归纳SAD固定床反应器和流化床反应器的结构及其适用条... 硫自养反硝化(SAD)是一种绿色低碳的污水脱氮技术,具有成本低、污泥产量少、无须外加有机碳源等优点,已成为污水脱氮技术研究的热点之一。阐述SAD填料组成与复合硫源填料的合成方法,归纳SAD固定床反应器和流化床反应器的结构及其适用条件,回顾SAD与电化学、异养反硝化、厌氧氨氧化耦合工艺等方面的研究进展,并总结SAD耦合技术的优缺点以及耦合工艺的脱氮特征。微生物的代谢功能是实现高效SAD的关键因素,列举不同代谢特性的SAD功能微生物种类,阐述代表性微生物Thiobacillus和Sulfurimonas在SAD过程中的反硝化特性及其生长条件。目前,SAD技术在填料、反应器和耦合工艺等方面取得显著进步,但仍面临诸多挑战,在SAD技术温度适应性、高处理负荷反应器设计以及工艺流程优化等方面进一步创新。 展开更多
关键词 反硝化 污水脱氮 污水处理 研究进展
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水氮处理对谷子内源激素脱落酸和光合作用特性的影响
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作者 于肖 牛佳红 +5 位作者 陈二影 秦岭 杨延兵 黎飞飞 刘振宇 管延安 《中国土壤与肥料》 CAS CSCD 北大核心 2024年第4期190-198,共9页
为探究氮肥与干旱处理对谷子生理特性的影响,以济谷22为材料,采用盆栽法研究不同水、氮处理对谷子内源激素脱落酸(ABA)、叶绿素含量、光合作用特性及水、氮利用效率的影响。设置3种水分处理:正常水分(CK,田间持水量的60%~70%)、苗期干旱... 为探究氮肥与干旱处理对谷子生理特性的影响,以济谷22为材料,采用盆栽法研究不同水、氮处理对谷子内源激素脱落酸(ABA)、叶绿素含量、光合作用特性及水、氮利用效率的影响。设置3种水分处理:正常水分(CK,田间持水量的60%~70%)、苗期干旱(W_(1),田间持水量的30%~40%)、孕穗期干旱(W_(2),田间持水量的30%~40%)及2种施氮量处理:施氮(N_(150),N 150 kg/hm^(2))、不施氮(N_(0)),生长期间旱棚防雨。结果表明:受到水分胁迫时,叶片中的ABA含量升高,施氮水平下升高幅度较大;根中ABA含量也会升高,但其在不施氮水平下升高幅度较大。开花期不同处理光-光合响应曲线有显著差异,苗期干旱施氮处理优势明显。开花期叶片荧光性能存在较大差异,受到水、氮胁迫时,光系统Ⅱ潜在的最大光化学效率、反应中心所吸收的光子中用于电子传递的量子产额值降低,反应中心所吸收光子中用于热耗散的量子比率上升,以吸收光能为基础的性能指数急剧下降,孕穗期干旱施氮处理的j点的相对可变荧光强度显著高于对照,孕穗期干旱且不施氮的以吸收光能为基础的性能指数最低,反映单位反应中心捕获的用于电子传递的能量值最高。不同水、氮处理的谷子抽穗后,随着时间的推移,SPAD值逐渐降低,施氮处理明显提高了叶片的SPAD值。不同处理间比较以施氮处理下苗期干旱水分利用效率最高,不施氮处理的氮素利用效率明显高于其他处理。同一水分处理下,施氮处理的水分利用效率显著高于不施氮处理,氮素利用效率表现为相反趋势。苗期干旱施氮处理通过提高叶片SPAD值、花期净光合速率,显著提升了光合作用,水分和氮肥利用率显著提高,保证谷子达到相对稳定的产量。 展开更多
关键词 谷子 施氮处理 水分胁迫 脱落酸 光合特性
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禾豆间作系统水分和根系分隔对牧草氮素吸收利用及转移的影响 被引量:1
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作者 王一帆 刘华清 +1 位作者 赵西宁 高晓东 《水土保持学报》 CSCD 北大核心 2024年第4期279-287,共9页
[目的]禾豆间作可兼顾生产和生态效益,提高氮素利用效率并减少氮肥污染。目前对不同水分条件下禾豆间作体系氮素利用吸收及转移分配过程尚不清晰。[方法]通过设置2时段总水量相同但间隔3,5天的不同频次水处理,结合根系分隔(不分隔、尼... [目的]禾豆间作可兼顾生产和生态效益,提高氮素利用效率并减少氮肥污染。目前对不同水分条件下禾豆间作体系氮素利用吸收及转移分配过程尚不清晰。[方法]通过设置2时段总水量相同但间隔3,5天的不同频次水处理,结合根系分隔(不分隔、尼龙网分隔、塑料板分隔)和氮同位素标记方法,研究间作禾豆牧草的地上生物量、氮素的吸收利用、固氮率和氮转移率。[结果]间作披碱草的地上生物量、氮含量和氮素累积量相较单作披碱草显著提升,而苜蓿间作相比单作均降低。在总水量持平的情况下,高频水分处理使牧草的地上生物量比中低频水分处理分别提高6.28%,17.32%,苜蓿的固氮率也在高频水处理下比中低频水处理分别提高39.82%,44.81%,但部分中低频水分处理下氮含量和氮素累积量显著高于高频水分处理(p<0.05),且促进氮素的转移。根系分隔使禾豆相互作用减弱,表现为根系分隔增加间作苜蓿的地上生物量、各部位氮含量及地上部氮素累积量,减小间作披碱草的对应指标。间作苜蓿的固氮和氮转移率表现为不分隔>尼龙网分隔>塑料板分隔。[结论]适度的水分调控可以提高禾豆间作的优势,且根系互作是促进豆科牧草生物固氮和氮转移的关键。 展开更多
关键词 禾豆间作 根系分隔 水分处理 氮素利用 氮转移效率
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温度对垃圾渗滤液生化处理过程中氨氮去除的影响研究 被引量:1
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作者 胡健 陈增丰 +2 位作者 马壮 王越婷 吴伟祥 《环境科技》 2024年第1期1-6,共6页
为解决垃圾渗滤液处理工程中常出现夏季高温导致生化污泥失活、出水氨氮不达标的问题,利用杭州市某垃圾中转站的渗滤液和活性污泥,探究了温度对垃圾渗滤液生化处理过程中氨氮去除的影响。通过小试试验探究得出,高温条件下活性污泥对氨... 为解决垃圾渗滤液处理工程中常出现夏季高温导致生化污泥失活、出水氨氮不达标的问题,利用杭州市某垃圾中转站的渗滤液和活性污泥,探究了温度对垃圾渗滤液生化处理过程中氨氮去除的影响。通过小试试验探究得出,高温条件下活性污泥对氨氮的去除效果随温度的升高而逐渐降低;当生化系统温度小于40℃时,简单的降温措施即可恢复污泥的活性;当活性污泥受到40℃以上的高温损伤后,生物膜结构受到破坏而彻底失活,生化系统对氨氮的去除率降至20%以下,此时仅通过降温措施并不能有效恢复活性,需重新接种污泥或添加硝化菌剂方能快速恢复氨氮去除功能。因此,在垃圾渗滤液处理工程中,应通过设置冷却塔等措施避免活性污泥处于40℃以上的高温环境中。 展开更多
关键词 温度 垃圾渗滤液 氨氮 生化处理 活性污泥
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