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施肥对金沙江干热河谷退化草地土壤微生物的影响 被引量:47
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作者 张彦东 孙志虎 沈有信 《水土保持学报》 CSCD 北大核心 2005年第2期88-91,共4页
在金沙江干热河谷区的退化草地上进行了2年的氮磷施肥试验,试验结束后分析了土壤特性及土壤微生物数量和生物量的变化。结果表明,在施氮量为5 ,15g/ (m2 ·a)时,土壤微生物的数量和生物量均没有明显变化,而当施氮量增加到2 5g/ (m2 ... 在金沙江干热河谷区的退化草地上进行了2年的氮磷施肥试验,试验结束后分析了土壤特性及土壤微生物数量和生物量的变化。结果表明,在施氮量为5 ,15g/ (m2 ·a)时,土壤微生物的数量和生物量均没有明显变化,而当施氮量增加到2 5g/ (m2 ·a)时,土壤微生物的数量和生物量比对照明显增加。施磷没有引起土壤微生物数量和生物量的明显增加。施氮和施磷均没有引起土壤细菌、真菌和放线菌组成的变化。这表明氮虽然影响土壤微生物的数量,但对土壤微生物的组成没有影响。施氮导致土壤硝态氮增加,但对氨态氮影响不大,硝态氮可能是影响土壤微生物数量的重要因素。施氮和施磷后植物群落地上生物量均出现增加的趋势,但土壤有机质没有明显增加。施氮和施磷也没有引起土壤pH和含水率的明显改变。我们的试验结果表明,在干热河谷退化草地生态系统。 展开更多
关键词 土壤微生物数量 金沙江干热河谷区 退化草地生态系统 土壤微生物群落 土壤硝态氮 地上生物量 土壤有机质 施肥试验 土壤特性 土壤细菌 植物群落 土壤pH 试验结果 无机肥料 施氮量 施磷 放线菌 氨态氮 含水率 组成 施用
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Grain quality changes and responses to nitrogen fertilizer of japonica rice cultivars released in the Yangtze River Basin from the 1950s to 2000s 被引量:34
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作者 Junfei Gu Jing Chen +3 位作者 Lu Chen Zhiqin Wang Hao Zhang Jianchang Yang 《The Crop Journal》 SCIE CAS CSCD 2015年第4期285-297,共13页
While the yield potential of rice has increased but little is known about the impact of breeding on grain quality, especially under different levels of N availability. In order to investigate the integrated effects of... While the yield potential of rice has increased but little is known about the impact of breeding on grain quality, especially under different levels of N availability. In order to investigate the integrated effects of breeding and N levels on rice quality 12 japonica rice cultivars bred in the past60 years in the Yangtze River Basin were used with three levels of N: 0 kg N ha-1, 240 kg N ha-1,and 360 kg N ha-1. During the period, milling quality(brown rice percentage, milled rice percentage, and head rice percentage), appearance quality(chalky kernels percentage, chalky size, and chalkiness), and eating and cooking quality(amylose content, gel consistency, peak viscosity, breakdown, and setback) were significantly improved, but the nutritive value of the grain has declined due to a reduction in protein content. Micronutrients, such as Cu, Mg, and S contents, were decreased, and Fe, Mn, Zn, Na, Ca, K, P, B contents were increased. These changes in grain quality imply that simultaneous improvements in grain yield and grain quality are possible through selection. Overall, application of N fertilizer decreased grain quality, especially in terms of eating and cooking quality. Under higher N levels, higher protein content was the main reason for deterioration of grain quality, although lower amylose content might contribute to improving starch pasting properties. These results suggest that further improvement in grain quality will depend on both breeding and cultivation practices, especially in regard to nitrogen and water management. 展开更多
关键词 Breeding Cultivation technique Grain quality JAPONICA rice nitrogenous FERTILIZER
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牛头岛深湾网箱养殖区底质溶液中的氮和磷 被引量:24
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作者 王小平 《中国水产科学》 CAS CSCD 1998年第3期126-128,共3页
目前有关海洋沉积物底质溶液中生原要素的研究报道较少。Ritenberg[5]研究了沉积物管样中NO3-N、NO2-N、NH4-N、PO4-P及SiO3-Si的垂直分布,探讨了生原要素的再生过程。国内GuHongkan... 目前有关海洋沉积物底质溶液中生原要素的研究报道较少。Ritenberg[5]研究了沉积物管样中NO3-N、NO2-N、NH4-N、PO4-P及SiO3-Si的垂直分布,探讨了生原要素的再生过程。国内GuHongkan等[6]研究了胶州湾底质溶液中氮和... 展开更多
关键词 珠海 网箱养殖 底质溶液 牛头岛
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辣椒高产优质施肥数学模型的研究 被引量:13
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作者 刘秀珍 李明山 《山西农业大学学报》 CAS 1994年第2期118-122,共5页
应用三因子二次通用旋转组合设计,研究了氮、磷、钾肥配合施用对辣椒产量和品质的影响。结果表明:氮、磷、钾配合施用对辣椒产量有明显的影响,试验结果达到了极显著水平,氮与磷;氮与钾,磷与钾对产量的互作效应为正的显著水平,配... 应用三因子二次通用旋转组合设计,研究了氮、磷、钾肥配合施用对辣椒产量和品质的影响。结果表明:氮、磷、钾配合施用对辣椒产量有明显的影响,试验结果达到了极显著水平,氮与磷;氮与钾,磷与钾对产量的互作效应为正的显著水平,配施后有相互增效作用。磷、钾可显著提高辣椒维生素C的含量,氮肥的作用较小,在本试验条件下,获得辣椒高产优质高效益的优化配方为纯N9.97~11.35kg/亩,P2O25.99~7.43kg/亩,K2O6.73~7.59kg/亩。 展开更多
关键词 辣椒 数学模型 施肥
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Control of aliphatic halogenated DBP precursors with multiple drinking water treatment processes: Formation potential and integrated toxicity 被引量:15
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作者 Yimeng Zhang Wenhai Chu +1 位作者 Dechang Yao Daqiang Yin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第8期322-330,共9页
The comprehensive control efficiency for the formation potentials(FPs) of a range of regulated and unregulated halogenated disinfection by-products(DBPs)(including carbonaceous DBPs(C-DBPs), nitrogenous DBPs(N... The comprehensive control efficiency for the formation potentials(FPs) of a range of regulated and unregulated halogenated disinfection by-products(DBPs)(including carbonaceous DBPs(C-DBPs), nitrogenous DBPs(N-DBPs), and iodinated DBPs(I-DBPs)) with the multiple drinking water treatment processes, including pre-ozonation, conventional treatment(coagulation–sedimentation, pre-sand filtration), ozone-biological activated carbon(O_3-BAC) advanced treatment, and post-sand filtration, was investigated. The potential toxic risks of DBPs by combing their FPs and toxicity values were also evaluated.The results showed that the multiple drinking water treatment processes had superior performance in removing organic/inorganic precursors and reducing the formation of a range of halogenated DBPs. Therein, ozonation significantly removed bromide and iodide,and thus reduced the formation of brominated and iodinated DBPs. The removal of organic carbon and nitrogen precursors by the conventional treatment processes was substantially improved by O_3-BAC advanced treatment, and thus prevented the formation of chlorinated C-DBPs and N-DBPs. However, BAC filtration leads to the increased formation of brominated C-DBPs and N-DBPs due to the increase of bromide/DOC and bromide/DON.After the whole multiple treatment processes, the rank order for integrated toxic risk values caused by these halogenated DBPs was haloacetonitriles(HANs)》haloacetamides(HAMs) 〉haloacetic acids(HAAs) 〉 trihalomethanes(THMs) 〉 halonitromethanes(HNMs) 》I-DBPs(I-HAMs and I-THMs). I-DBPs failed to cause high integrated toxic risk because of their very low FPs. The significant higher integrated toxic risk value caused by HANs than other halogenated DBPs cannot be ignored. 展开更多
关键词 Carbonaceous disinfection by-products(C-DBPs) nitrogenous disinfection by-products(N-DBPs) Iodinated disinfection by-products(I-DBPs) Formation potential Toxic risk Drinking water treatment plant(DWTP)
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基肥氮素水平与人参碳氮代谢 被引量:11
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作者 张平 索滨华 +1 位作者 郭世伟 刘兆荣 《吉林农业大学学报》 CAS CSCD 1995年第2期63-67,共5页
为探讨人参氮素营养规律,在基肥不同施氮量(0,10,20,30,40g/m2)条件下.采用(14)C示踪方法和化学分析方法,测定了人参对(14)CO2同化能力,NR活性,N、P、K营养的吸收,糖、蛋白N、非蛋白N以及... 为探讨人参氮素营养规律,在基肥不同施氮量(0,10,20,30,40g/m2)条件下.采用(14)C示踪方法和化学分析方法,测定了人参对(14)CO2同化能力,NR活性,N、P、K营养的吸收,糖、蛋白N、非蛋白N以及人参皂甙的变化。结果表明,四龄参在基施氮肥10g/m2,(14)CO2同化能力,NR活力最高;基施氮肥30g/m2时吸K量下降;基施氮肥40g时吸N量、NPN(蛋白N)与PN(非蛋白N)、NPN/PN值下降,C/N值下降43%,总可溶糖、蔗糖下降,淀粉增加。五龄参时,基施氮肥40g/m2处理组还原糖增加60%左右,皂甙含量下降。 展开更多
关键词 人参 氮肥 代谢
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不同地点、播期和氮肥施用量对特高芥酸油菜经济和品质性状的影响 被引量:12
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作者 刘念 汤天泽 +3 位作者 范其新 蒙大庆 李芝凡 陈军 《甘肃农业大学学报》 CAS CSCD 北大核心 2015年第3期68-72,79,共6页
以特高芥酸‘绵油309’为材料,在四川绵阳选择了松垭、金峰、梓潼3个地点,通过分期播种和不同氮肥施用量试验研究油菜经济和品质性状的差异.结果表明:地点、播期和氮肥施用量对‘绵油309’的经济和品质性状具有较大影响,其中播期的影响... 以特高芥酸‘绵油309’为材料,在四川绵阳选择了松垭、金峰、梓潼3个地点,通过分期播种和不同氮肥施用量试验研究油菜经济和品质性状的差异.结果表明:地点、播期和氮肥施用量对‘绵油309’的经济和品质性状具有较大影响,其中播期的影响最为显著.千粒质量、产量和芥酸含量为松垭种植油菜最高,角果数、棕榈酸、油酸、亚油酸、花生烯酸和含油率为金峰种植油菜最高,每角粒数、硬脂酸和亚麻酸梓潼种植油菜最高.松垭和金峰种植油菜的大部分性状变异系数小,稳定性好.综合播期和氮肥对油菜的影响规律,建议‘绵油309’在9月27日左右直播,氮肥用量180kg/hm2,油菜的经济和品质性状可以达到较好的水平. 展开更多
关键词 高芥酸油菜 地点 播期 氮肥 品质
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玉米氮、磷、钾肥最佳施用量探讨 被引量:10
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作者 周建新 罗敏 《贵州农业科学》 CAS 2001年第6期26-27,共2页
运用“34 14”试验设计 ,探讨黔西南州中上等肥力旱地玉米氮、磷、钾肥料的最佳配比。试验结果表明 :667m2施尿素 2 6kg、普钙 37.5 kg、氯化钾 2 0 kg,玉米单产最高达 618.4 kg;经济施肥 667m2施尿素 13kg、普钙 37.5 kg、氯化钾 6.7kg... 运用“34 14”试验设计 ,探讨黔西南州中上等肥力旱地玉米氮、磷、钾肥料的最佳配比。试验结果表明 :667m2施尿素 2 6kg、普钙 37.5 kg、氯化钾 2 0 kg,玉米单产最高达 618.4 kg;经济施肥 667m2施尿素 13kg、普钙 37.5 kg、氯化钾 6.7kg,肥效好 ,单产为 5 65 .6kg。建立了肥料效应函数方程 y=4 38.79+40 .86N+43.2 5 P+13.35 K+0 .2 4 NP+2 .4 5 NK- 3.39PK- 2 .2 3N2 - 1.5 3P2 - 1.2 1K2。 展开更多
关键词 玉米 最佳施用量 配比
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Carbonaceous and nitrogenous disinfection by-product formation in the surface and ground water treatment plants using Yellow River as water source 被引量:7
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作者 Yukun Hou Wenhai Chu Meng Ma 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第7期1204-1209,共6页
This work investigated the formation of carbonaceous and nitrogenous disinfection by-products (C-DBPs, N-DBPs) upon chlorination of water samples collected from a surface water and a ground water treatment plant (S... This work investigated the formation of carbonaceous and nitrogenous disinfection by-products (C-DBPs, N-DBPs) upon chlorination of water samples collected from a surface water and a ground water treatment plant (SWTP and GWTP) where the conventional treatment processes, i.e., coagulation, sedimentation, and filtration were employed. Twenty DBPs, including four trihalomethanes, nine haloacetic acids, seven N-DBPs (dichloroacetamide, trichloroacetamide, dichloroacetonitrile, trichloroacetonitrile, bromochloroace- tonitrile, dibromoacetonitrile and trichloronitromethane), and eight volatile chlorinated compounds (dichloromethane (DCM), 1,2-dichloroethane, tetrachloroethylene, chlorobenzene, 1,2-dichlorobenzene, 1,4-dichlorobenzene, 1,2,3-trichlorobenzene and 1,2,4- trichlorobenzene) were detected in the two WTPs. The concentrations of these contaminants were all below their corresponding maximum contamination levels (MCLs) regulated by the Standards for Drinking Water Quality of China (GB5749-2006) except for DCM (17.1 ~tg/L detected vs. 20 μg/L MCL). The SWTP had much higher concentrations of DBPs detected in the treated water as well as the DBP formation potentials tested in the filtered water than the GWTP, probably because more precursors (e.g., dissolved organic carbon, dissolved organic nitrogen) were present in the water source of the SWTE 展开更多
关键词 carbonaceous disinfection by-products nitrogenous disinfection by-products formation potential free chlorine watertreatment plant
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Recent progress in electrochemical C–N coupling reactions 被引量:3
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作者 Yuan Zhong Hailong Xiong +2 位作者 Jingxiang Low Ran Long Yujie Xiong 《eScience》 2023年第1期26-37,共12页
Electrochemical C–N coupling has generated intense research interest as a promising approach to reduce carbon and nitrogen emissions and store excess renewable electricity in valuable chemicals(e.g.,urea,amides,and a... Electrochemical C–N coupling has generated intense research interest as a promising approach to reduce carbon and nitrogen emissions and store excess renewable electricity in valuable chemicals(e.g.,urea,amides,and amines).In this review,we discuss the emerging trends in electrocatalytic C–N coupling reactions using CO_(2) and inorganic nitrogenous species(i.e.,dinitrogen(N_(2))),nitrate(NO_(2)^(-)),nitrite(NO_(3)^(-)),and ammonia(NH_(3))as raw materials.The related reaction mechanisms and potential design principles for advanced electrocatalysts are outlined.In addition,the effects of different reactors,including H-cells,membrane-based flow reactors,and membrane electrode assembly electrolyzers,on the coupling reactions are emphasized.Finally,the current challenges and future opportunities in this field are described.We aim to provide an up-to-date overview of the electrochemical C–N coupling system to advance progress toward its practical application. 展开更多
关键词 Electrochemical C-N coupling reactions Carbon dioxide Inorganic nitrogenous species nitrogenous compounds Reactor designs
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Characteristics of microbial community functional structure of a biological coking wastewater treatment system 被引量:7
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作者 Dev Raj Joshi Yu Zhang +2 位作者 Hong Zhang Yingxin Gao Min Yang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第1期105-115,共11页
Nitrogenous heterocyclic compounds are key pollutants in coking wastewater; however, the functional potential of microbial communities for biodegradation of such contaminants during biological treatment is still elusi... Nitrogenous heterocyclic compounds are key pollutants in coking wastewater; however, the functional potential of microbial communities for biodegradation of such contaminants during biological treatment is still elusive. Herein, a high throughput functional gene array(Geo Chip 5.0)in combination with Illumina Hi Seq2500 sequencing was used to compare and characterize the microbial community functional structure in a long run(500 days) bench scale bioreactor treating coking wastewater, with a control system treating synthetic wastewater. Despite the inhibitory toxic pollutants, Geo Chip 5.0 detected almost all key functional gene(average61,940 genes) categories in the coking wastewater sludge. With higher abundance, aromatic ring cleavage dioxygenase genes including multi ring1,2 diox; one ring2,3 diox; catechol represented significant functional potential for degradation of aromatic pollutants which was further confirmed by Illumina Hi Seq2500 analysis results. Response ratio analysis revealed that three nitrogenous compound degrading genes-nbz A(nitro-aromatics), tdn B(aniline), and scn ABC(thiocyanate) were unique for coking wastewater treatment, which might be strong cause to increase ammonia level during the aerobic process. Additionally, Hi Seq2500 elucidated carbozole and isoquinoline degradation genes in the system. These findings expanded our understanding on functional potential of microbial communities to remove organic nitrogenous pollutants;hence it will be useful in optimization strategies for biological treatment of coking wastewater. 展开更多
关键词 Coking wastewater GeoChip Illumina HiSeq Functional genes nitrogenous pollutants
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叶面喷肥对主干形整枝桃叶片营养和果实品质的影响 被引量:7
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作者 章雅靓 黄朱凤 +1 位作者 赵春德 王世平 《上海交通大学学报(农业科学版)》 2005年第1期15-18,共4页
本文以3年生主干形整枝的“新川中岛”桃为试材,探讨了叶面施肥对叶片叶绿素含量,含氮量及果实品质的影响。结果表明:叶面喷施含氮120mg·L-1和240mg·L-1的复合液肥可以延缓叶片衰老过程中叶绿素含量的下降,果实含酸量下降,固... 本文以3年生主干形整枝的“新川中岛”桃为试材,探讨了叶面施肥对叶片叶绿素含量,含氮量及果实品质的影响。结果表明:叶面喷施含氮120mg·L-1和240mg·L-1的复合液肥可以延缓叶片衰老过程中叶绿素含量的下降,果实含酸量下降,固酸比提高,品质有所改善。 展开更多
关键词 主干形 整枝 果实品质 叶面喷肥 桃叶 固酸比 叶片叶绿素 延缓 复合液 影响
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Electrocatalytic synthesis of C-N coupling compounds from CO_(2) and nitrogenous species 被引量:1
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作者 Zheng Zhang Danyang Li +12 位作者 Yunchuan Tu Jiao Deng Huiting Bi Yongchao Yao Yan Wang Tingshuai Li Yongsong Luo Shengjun Sun Dongdong Zheng Sónia A.C.Carabineiro Zhou Chen Junjiang Zhu Xuping Sun 《SusMat》 SCIE EI 2024年第2期51-74,共24页
The electrocatalytic synthesis of C-N coupling compounds from CO_(2) and nitrogenous species not only offers an effective avenue to achieve carbon neutral-ity and reduce environmental pollution,but also establishes a ... The electrocatalytic synthesis of C-N coupling compounds from CO_(2) and nitrogenous species not only offers an effective avenue to achieve carbon neutral-ity and reduce environmental pollution,but also establishes a route to synthesize valuable chemicals,such as urea,amide,and amine.This innovative approach expands the application range and product categories beyond simple carbona-ceous species in electrocatalytic CO_(2) reduction,which is becoming a rapidly advancing field.This review summarizes the research progress in electrocatalytic urea synthesis,using N_(2),NO_(2)^(-),and NO_(3)^(-)as nitrogenous species,and explores emerging trends in the electrosynthesis of amide and amine from CO_(2) and nitro-gen species.Additionally,the future opportunities in this field are highlighted,including electrosynthesis of amino acids and other compounds containing C-N bonds,anodic C-N coupling reactions beyond water oxidation,and the catalytic mechanism of corresponding reactions.This critical review also captures the insights aimed at accelerating the development of electrochemical C-N coupling reactions,confirming the superiority of this electrochemical method over the traditional techniques. 展开更多
关键词 C-N coupling CO_(2) reduction ELECTROCATALYSIS nitrogenous species reaction mechanism
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秸秆和氮肥不同配比影响平邑甜茶幼苗的生长和对氮素的吸收、分配和利用 被引量:7
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作者 崔同丽 姜远茂 +1 位作者 彭福田 魏绍冲 《植物生态学报》 CAS CSCD 北大核心 2012年第2期169-176,共8页
为探讨秸秆和氮肥不同配比对平邑甜茶(Malus hupehensis)植株生长和氮素吸收、分配和利用的影响,采用15N同位素示踪技术,以二年生盆栽平邑甜茶为试材,研究了不同秸秆和氮肥配比条件下平邑甜茶的生长、15N尿素吸收利用和土壤碳氮比等参数... 为探讨秸秆和氮肥不同配比对平邑甜茶(Malus hupehensis)植株生长和氮素吸收、分配和利用的影响,采用15N同位素示踪技术,以二年生盆栽平邑甜茶为试材,研究了不同秸秆和氮肥配比条件下平邑甜茶的生长、15N尿素吸收利用和土壤碳氮比等参数,发现秸秆和氮肥不同配比对平邑甜茶植株的生长及15N-尿素的吸收、分配和利用具有不同的影响。园土和秸秆比在45:1的水平,同时配施氮肥(N300mg·kg-1)时,植株株高、茎粗和植株总干重的值最高,分别为85.33cm、8.05mm和74.68g;植株的全氮、15N吸收量和利用率也最大,分别为0.938g、0.029g和9.74%。不加秸秆而仅施加氮肥(N200mg·kg-1)的对照(CK)的根冠比最大,为1.54,显著高于其他各种处理。各试验处理地上部分从肥料中吸收分配到的15N量对地上部分全氮量的贡献率(Ndff)均大于地下部分,且CK各器官Ndff值最高,地上部分和地下部分分别为7.94%和4.69%。除CK外,各处理15N分配率均是地上部>地下部。秸秆的施用显著提高了土壤的有机质、全氮含量和土壤有机质C/N比。相关性分析结果表明,土壤有机质C/N比与植株地下部分Ndff值有极显著负相关性(p<0.01),与植株整株Ndff值有显著负相关性(p<0.05)。建议果园秸秆配施氮肥时,控制秸秆施用量在45:1水平,氮肥在200-300mg·kg-1之间较好。 展开更多
关键词 吸收 分配 平邑甜茶 氮素 秸秆 利用率
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Preparation of a novel lactose-lignin hydrogel catalyst with self-reduction capacity for nitrogenous wastewater treatment
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作者 Fan Zhang Yanzhu Guo +4 位作者 Xianhong Wu Ce Gao Qingda An Zhongjian Tian Runcang Sun 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2024年第9期25-36,共12页
A novel carboxylated lactose/sodium lignosulfonate/polyacrylic acid hydrogel composites with self-reduction capacity was successfully synthesized by self-assembly method.The hydrogel with well-developed porous structu... A novel carboxylated lactose/sodium lignosulfonate/polyacrylic acid hydrogel composites with self-reduction capacity was successfully synthesized by self-assembly method.The hydrogel with well-developed porous structure provided abundant anchoring points and reduction capacity for transforming Ag^(+)into silver nanoparticles.Silver nanoparticles dispersed among the network of hydrogel and the composites exhibited catalytic capacity.The catalytic performance was evaluated via degradation of p-nitrophenol,rhodamine B,methyl orange and methylene blue,which were catalyzed with corresponding reaction rate constants of 0.04338,0.07499,0.04891,and 0.00628 s^(–1),respectively.In addition,the catalyst exhibited stable performance under fixed-bed condition and the corresponding conversion rate still maintained more than 80%after 540 min.Moreover,the catalytic performance still maintained effective in tap water and simulated seawater.The catalytic efficiency still remained 99.7%with no significant decrease after 8 cycles. 展开更多
关键词 carboxylated lactose Ag NPs self-reduction nitrogenous wastewater
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Insight into the ammonia torrefaction and pyrolysis system of cellulose:Unraveling the evolution of chemical structure and nitrogen migration mechanism 被引量:1
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作者 Shanjian Liu An Zhao +3 位作者 Jia Liu Mengqian Yin Fupeng Huang Dongmei Bi 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第3期135-147,I0005,共14页
This study aimed to investigate the mechanism of nitrogen doping,migration,and conversion during ammonia torrefaction and also explore the evolution law of the chemical structure of cellulose.The results showed that t... This study aimed to investigate the mechanism of nitrogen doping,migration,and conversion during ammonia torrefaction and also explore the evolution law of the chemical structure of cellulose.The results showed that the ammonia torrefaction pretreatment could significantly optimize the distribution of nitrogen and oxygen elements in cellulose.The carbon skeleton first captured the active nitrogenous radicals to form-NHn-N,and pyridine-N and pyrrole-N originated from the conversion of-NHn-N.The existence of C=O played a major role in the immobilization of nitrogen.The nitrogen in bio-oil exists mainly in the form of five-and six-membered heterocycles.The correlation analysis showed that the main precursors for the formation of nitrogenous heterocyclic compounds were five-membered Oheterocyclic compounds.Finally,the product distribution characteristics in the torrefaction-pyrolysis systems were summarized,and the nitrogen doping and conversion mechanisms were proposed.This study expanded the boundaries of cellulose pretreatment and the production of high-value chemicals. 展开更多
关键词 Ammonia torrefaction CELLULOSE nitrogenous compounds Structure evolution nitrogen migration
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Recent advances in application of moving bed bioreactors for wastewater treatment from recirculating aquaculture systems: A review 被引量:4
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作者 Abubakar Shitu Gang Liu +6 位作者 Aliyu Idris Muhammad Yadong Zhang Musa Abubakar Tadda Wanhe Qi Dezhao Liu Zhangying Ye Songming Zhu 《Aquaculture and Fisheries》 2022年第3期244-258,共15页
In recent years,government investments in implementing restrictive public policies on the treatment and discharge of effluents from the aquaculture industry have increased.Hence,efficient and cleaner methods for aquac... In recent years,government investments in implementing restrictive public policies on the treatment and discharge of effluents from the aquaculture industry have increased.Hence,efficient and cleaner methods for aquaculture production are needed.Recirculating aquaculture systems(RAS)offers water conservation by recycling the treated aquaculture water for reuse.RAS wastewater treatment using a moving bed bioreactors(MBBRs)process has been considered well suited for maintaining good water quality,thereby making fish farming more sustainable.Currently,improvements were achieved in tackling the influence of salinity,organic matter,disinfectant,and bioreactor start-up process on the MBBR performance efficiency.This review highlights an updated overview of recent development made using MBBR to treat the residual water from RAS.Precisely,nitrification and simultaneous nitrification-denitrification(SND),and other hybrid processes for nitrogen removal were elucidated.Finally,future challenges and prospects of MBBRs in RAS facilities that need to be considered were also proposed. 展开更多
关键词 Ammonia removal Biofilm carriers SUSTAINABILITY SALINITY nitrogenous compound Accelerated start-up
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反刍动物碳水化合物和含氮化合物的消化代谢规律刍议 被引量:5
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作者 郭冬生 彭小兰 夏维福 《草食家畜》 2007年第2期36-38,共3页
碳水化合物和含氮化合物是反刍动物营养的重要来源,碳水化合物在瘤胃中降解为挥发性脂肪酸(VFA)和酮酸;含氮化合物降解为NH3和CO2;瘤胃中的微生物利用酮酸和NH3合成MCP,为瘤胃微生物和动物提供能量与蛋白营养。本文从反刍动物碳水化合... 碳水化合物和含氮化合物是反刍动物营养的重要来源,碳水化合物在瘤胃中降解为挥发性脂肪酸(VFA)和酮酸;含氮化合物降解为NH3和CO2;瘤胃中的微生物利用酮酸和NH3合成MCP,为瘤胃微生物和动物提供能量与蛋白营养。本文从反刍动物碳水化合物和含氮化合物的消化吸收,代谢和营养作用等方面阐述了反刍动物碳水化合物和含氮化合物的规律。 展开更多
关键词 反刍动物 碳水化合物 含氮化合物
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Yield and Quality of Forage Oat (<i>Avena sativa</i>L.) Cultivars as Affected by Seed Inoculation with Nitrogenous Strains 被引量:3
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作者 Muhammad Saleem M. Shahid Ibni Zamir +7 位作者 Ihtishamul Haq M. Zahid Irshad M. Kamran Khan M. Asim Qamaruz Zaman Ihtisham Ali Aman Khan Saeedur Rehman 《American Journal of Plant Sciences》 2015年第19期3251-3259,共9页
Nitrogen availability can be enhanced with the application of nitrogen fixing bacteria and it may be helpful in increasing forage yield and improving quality of oat. Therefore, a field trial to evaluate the effect of ... Nitrogen availability can be enhanced with the application of nitrogen fixing bacteria and it may be helpful in increasing forage yield and improving quality of oat. Therefore, a field trial to evaluate the effect of seed inoculation with nitrogen fixing bacteria on forage yield and quality of oat was carried out at Agronomic Research Area, University of Agriculture, Faisalabad during Rabi season 2013-14. The experiment was laid out in Randomized Complete Block Design (RCBD) with factorial arrangements using three replications. The experiment was comprised of two integrated approaches. The first approach was oat cultivars consisting of four treatments, V1 (AVON), V2 (S-2000), V3 (S-2011) and V4 (PD2LV65) and the second approach was seed inoculation consisting of three treatments, S0 (control), S1 (Azotobacter spp.), S2 (Azospirillum spp.). Fisher’s analysis of variance technique was used for statistically interpretation of data by using least significant difference (LSD) test at 5% level of probability. Nitrogen fixing bacteria significantly affect the germination count (m2), plant height (cm), number of tillers (m2), number of leaves per tiller, leaf area per tiller (cm2), green forage yield (t·ha-1) and dry matter yield (t ha-1). The maximum green forage yield (85.2 t·ha-1), dry matter yield (14.1 t ·ha-1) and crude protein (11.5%) were recorded where Azotobacter inoculation was applied. The interaction between cultivars and nitrogenous strains was significant for green forage yield (t·ha-1), dry matter yield (t·ha-1) and crude protein (%). Conclusion showed that cultivar Sargodha-2011 which was inoculated with Azotobacter spp. gave higher forage yield of good quality. 展开更多
关键词 Oat CULTIVARS nitrogenous STRAINS Quality and FORAGE Yield
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Effects of Combined Application of Biochar-based Organic Fertilizer and Reduced Nitrogen Fertilizer on Soil Enzyme Activity and Yield of Purple Cabbage(Brassica oleracea var.capita rubra)in Yuanmou County
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作者 Ben YANG Xiaoying LI +2 位作者 Yuechao WANG Mengjie CHEN Xiaoqin CHEN 《Agricultural Biotechnology》 CAS 2023年第2期76-83,共8页
[Objectives]In response to the issue of soil improvement in Yuanmou County,the effects of combined application of biochar-based organic fertilizer and reduced nitrogen fertilizer on soil nutrients,soil enzyme activity... [Objectives]In response to the issue of soil improvement in Yuanmou County,the effects of combined application of biochar-based organic fertilizer and reduced nitrogen fertilizer on soil nutrients,soil enzyme activity,and yield of purple cabbage(Brassica oleracea var.capita rubra)were investigated in the field base of Institute of Thermal Zone Ecological Agriculture,Yunnan Academy of Agricultural Sciences in Yuanmou County.[Methods]A total of 13 treatments were set up by applying biochar-based organic fertilizer at three levels of 15,30 and 45 t/hm^(2)(T_(1),T_(2),T_(3)),combined with top application of nitrogen fertilizer(urea)at four levels:375(N_1),300(N_(2)),225(N_(3))and 0 kg/hm^(2),with non-fertilizing treatment as control check(CK),in order to explore the optimal ratio for the combined application of biochar-based organic fertilizer with nitrogen fertilizer.[Results]The application of biochar-based organic fertilizer could significantly improve soil nutrients,enzyme activity,and purple cabbage yield.The improvement effect of combined application with nitrogen fertilizer was higher than that of single application of biochar-based organic fertilizer,and the improvement effect was enhanced with the application amount of biochar-based organic fertilizer increasing.The contents of organic matter and total nitrogen were the highest in treatment T_(3)N_(3),of which the values increased by 81.39%and 56.09%compared with the CK,respectively.The contents of soil hydrolyzable nitrogen,available phosphorus,and available potassium were all the highest under treatment T_(3)N_(2),with increases of 92.76%,171.01%and 235.50%,respectively.There was a significant positive correlation between the activity of soil catalase,urease,and sucrase and organic matter,total nitrogen,and available nutrients.The overall soil enzyme activity was relatively higher in treatment T_(3)N_(2).The yield of purple cabbage treated with biochar-based organic fertilizer combined with nitrogen fertilizer could reach 85750 kg/hm^(2),which was 94.78%hi 展开更多
关键词 Soil enzyme activity YIELD Biochar-based organic fertilizer nitrogenous fertilizer Purple cabbage
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