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Human activities aggravate nitrogen-deposition pollution to inland water over China

National Science Review 2020年第2期7卷 430-440页

作者： Yang Gao Feng Zhou Philippe Ciais Chiyuan Miao Tao Yang Yanlong jia Xudong Zhou Butterbach-Bahl Klaus Tiantian Yang Guirui Yu Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Sino-French Institute for Earth System Science College of Urban and Environmental Sciences Peking University Laboratoire des Sciences du Climat et de l'Environnement CEA CNRS UVSQ State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Center for Global Change and Water Cycle Hohai University Institute for Meteorology and Climate Research Atmospheric Environmental Research Karlsruhe Institute of Technology Department of Civil and Environmental Engineering University of California

In the past three decades, China ha. built more tha. 87 000 dams with a storage capacity of ≈6560 km3and the total surface area of inland water ha. increased by 6672 km2. Leaching of N from fertilized soils to rivers is the main source of N pollution in China, but the exposure of a growing inland water area to direct atmospheric N deposition and N leaching caused by N deposition on the terrestrial ecosystem, together with increased N deposition and decreased N flow, also tends to raise N concentrations in most inland waters. The contribution of this previously ignored source of N deposition to freshwaters is estimated in this study, as well as mitigation strategies. The results show tha. the annual amounts of N depositions ranged from 4.9 to 16.6 kg · ha.1· yr-1in the 1990 s to exceeding 20 kg · ha.1· yr-1in the 2010 s over most of regions in China, so the total mass of N(the net contribution of N deposition to the increase in N concentration) for lakes, rivers and reservoirs cha.ge from 122.26 Gg N · yr-1in the 1990 s to 237.75 Gg N· yr-1in the 2010 s. It is suggested tha. reducing the N deposition from various sources, shortening the water-retention time in dams and decreasing the degree of regulation for rivers are three main measures for preventing a continuous increase in the N-deposition pollution to inland water in China.

关键词： N deposition N concentration dam water area human activity

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沙冬青生物碱对MDCC-MSB1细胞增殖及细胞线粒体膜电位的影响

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中国兽医学报 2011年第2期31卷 232-236页

作者：哈利张惠英贾宁方梅甘肃省疫病预防控制中心甘肃兰州730046 甘肃省酒泉市人民医院甘肃酒泉735000 甘肃农业大学动物医学院甘肃兰州730070

采用体外细胞培养技术、噻唑蓝(MTT)还原法、流式细胞技术检测梯度浓度沙冬青总生物碱对体外培养鸡马立克氏病肿瘤HDCC-MSB1细胞株的增殖抑制及对线粒体膜电位的影响。结果显示,沙冬青生物碱可显著抑制HDCC-MSB1细胞增殖,且这种抑制具... 详细信息

采用体外细胞培养技术、噻唑蓝(MTT)还原法、流式细胞技术检测梯度浓度沙冬青总生物碱对体外培养鸡马立克氏病肿瘤HDCC-MSB1细胞株的增殖抑制及对线粒体膜电位的影响。结果显示,沙冬青生物碱可显著抑制HDCC-MSB1细胞增殖,且这种抑制具有剂量和时间效应关系。经沙冬青生物碱作用的HDCC-MSB1细胞培养样本中有明显的DNA低含量颗粒("亚G1期"峰),细胞周期各时相分布发生改变,细胞增殖在G1被阻滞。细胞线粒体膜电位(△Ψm)明显下降,也呈现出剂量和时间效应关系。结果表明,沙冬青生物碱对HDCC-MSB1细胞增殖有显著抑制效应,且抑制依赖于诱导HDCC-MSB1细胞线粒体膜电位(△Ψm)的下降,并进一步诱导了该细胞的凋亡。

关键词：沙冬青生物碱 HDCC-MSB1细胞线粒体膜电位(△Ψm) 增殖抑制

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Trees species’ dispersal mode and ha.itat heterogeneity sha.e negative density dependence in a temperate forest

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Forest Ecosystems 2023年第5期10卷 589-596页

作者： Lishunan Yang Daniel J.Johnson Zhichun Yang Xiaocha. Yang Qiulong Yin Ying Luo Zha.qing ha. Shihong jia School of Ecology and Environment Northwestern Polytechnical UniversityXi’anShaanxi710072China Sha.nxi Key Laboratory of Qinling Ecological Intelligent Monitoring and Protection Northwestern Polytechnical UniversityXi’anShaanxi710072China School of Forest Fisheriesand Geomatics SciencesUniversity of FloridaGainesvilleFLUSA School of Geography and Tourism Shaanxi Normal UniversityXi’anShaanxi710062China

Conspecific negative density dependence(CNDD)is a potentially important mecha.ism in maintaining species *** previous evidence showed ha.itat heterogeneity and species’dispersal modes affect the strength of CNDD at early life stages of trees(e.g.,seedlings),it remains unclear how they affect the strength of CNDD at later life *** examined the degree of spatial aggregation between saplings and trees for species dispersed by wind and gravity in four topographic ha.itats within a 25-ha.temperate forest dynamic plot in the Qinling Mountains of central *** used the replicated spatial point pattern(RSPP)analysis and bivariate paircorrelation function(PCF)to detect the spatial distribution of saplings around trees at two scales,15 and 50 m,*** the signal was not apparent across the whole study region(or 25-ha.,it is distinct on isolated areas with specific cha.acteristics,suggesting tha. these cha.acteristics could be important factors in ***,we found tha. the gravity-dispersed tree species experienced CNDD across ha.itats,while for wind-dispersed species CNDD was found in gully,terrace and low-ridge *** study suggests tha. neglecting the ha.itat heterogeneity and dispersal mode can distort the signal of CNDD and community assembly in temperate forests.

关键词： Biodiversity Conspecific negative density dependence Dispersal Replicated point patterns Temperate forest Topographic ha.itat

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Fabrication and growth mecha.ism of one-dimensional Heusler alloy nanostructures with different morphologies on anodic aluminum oxide template by magnetron sputtering

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Frontiers of Materials Science 2022年第3期16卷 219-229页

作者： Xiaoyu MA Guifeng CHEN Xiaoming Zha.G Taoyuan jia Weiqi Zha. Zha.jun MO Heyan LIU Xuefang DAI Guodong LIU School of Materials Science and Engineering Hebei University of TechnologyTianjin 300130China School of Materials Science and Engineering Tianjin University of TechnologyTianjin 300384China

Heusler alloys are a kind of intermetallic compounds with highly-ordered arrangement of *** attractive functional materials ha.e been developed in Heusler *** to the application requirements of materials in new-generation electronic devices and spintronics devices,one-dimensional nanostructured Heusler alloys with special functions are *** this work,it is proposed to grow one-dimensional Heusler alloy nanostructures(1D-ha.NSs)by magnetron sputtering plus anodic aluminum oxide(AAO)*** with different sha.es,amorphous-coated(AC)nanowires and nanotubes were successfully grown for several Heusler *** nanowires are the unique products of our *** alloy nanotubes are reported for the first *** one-dimensional nanostructures grow on the surface of the AAO substrate rather tha. in the *** top of the pore wall is the nanostructure growth point,the sha.e of which determines the morphology of the nanostructures.A general growth mecha.ism model of one-dimensional nanostructures on AAO template was established and further confirmed by experimental observation.

关键词： Heusleralloy one-dimensional nanostructure magnetron sputtering

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Effects of plant density and nitrogen rate on cotton yield and nitrogen use in cotton stubble retaining fields

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Journal of Integrative Agriculture 2021年第8期20卷 2090-2099页

作者： WANG Shi-hong MAO Li-li SHI jia-liang NIE Jun-jun SONG Xian-liang SUN Xue-zhen Agronomy College Shandong Agricultural UniversityTai’an 271018P.R.China Liaocheng Academy of Agricultural Sciences Liaocheng 252000P.R.China Dezhou Academy of Agricultural Sciences Dezhou 253000P.R.China

Increasing nitrogen(N)rate could accelerate the decomposition of crop residues,and then improve crop yield by increasing N availability of soil and N uptake of ***,it is not clear whether N rate and plant density should be modified after a long period of cotton stubble return with high N *** study seeks to assess the effects of N rate and plant density on cotton yield,N use efficiency,leaf senescence,soil inorganic N,and apparent N balance in cotton stubble return fields in Liaocheng,China,in 2016 and *** plant densities 5.25(D_(5.25)),6.75(D_(6.75))and 8.25(D_(8.25))plants m^(-2) and five N rates 0(N_(0)),105(N_(105)),210(N_(210)),315(N315),and 420(N420)kg ha.(-1) were *** to the combination used by local farmers(D_(5.25)N_(315)),a 33.3%N reduction and a 28.6%increase in plant density(D_(6.75)N_(210))can maintain high cotton yield,while a 66.7%N reduction at 6.75 plants m^(-2)(D_(6.75)N_(105))can only achieve high yield in the first *** yield increased with the increase of N rate and plant density,and the highest yield was obtained under 420 kg N ha.(-1) at 8.25 plants m^(-2)(D_(8.25)N_(420))across the two years under *** to D5.25N315,N agronomic efficiency(NAE)and N recovery efficiency(NRE)in D_(6.75)N_(210) increased by 30.2 and 54.1%,respectively,and NAE and NRE in D6.75N105 increased by 104.8 and 88.1%,*** inorganic N decreased sha.ply under 105 kg N ha.(-1),but no cha.ge was found under 210 kg N ha.(-1) at 6.75 plants m^(-2).N deficit occurred under 105 kg N ha.(-1),but it did not occurr under 210 kg N ha.(-1) at 6.75 plants m^(-2).Net photosynthetic rate and N concentration of leaves under N rate ranging from 210 to 420 kg ha.(-1) were higher tha. those under N rate of 0 or 105 kg N ha.(-1) at all three *** findings suggest tha. D6.75N210 is a superior combination in cotton stubble retaining fields in the Yellow River Valley and other areas with similar ecologies.

关键词： leaf senescence N application rate N use efficiency seed cotton yield soil apparent N surplus

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试论唐宋词中女性形象特征

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廊坊师范学院学报 2005年第2期21卷 32-37页

作者：哈嘉莹对外经济贸易大学中文系北京100029

词与诗相比,更具备几分阴柔气质,这与词中大量的女性形象描写是分不开的。男女作家笔下的女性形象是不同的。男性作家笔下的女性以男性视角出之,与男性自身有着千丝万缕的关联。而女性作家笔下的女性形象更多的是女性的自身写照。男女... 详细信息

词与诗相比,更具备几分阴柔气质,这与词中大量的女性形象描写是分不开的。男女作家笔下的女性形象是不同的。男性作家笔下的女性以男性视角出之,与男性自身有着千丝万缕的关联。而女性作家笔下的女性形象更多的是女性的自身写照。男女作家笔下的女性形象在某些方面又是相同的,这与男性女性无关,而是封建时代强加给人们的普遍意识。

关键词：男性词人女性词人唐宋词女性形象

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Phylogenetic and Structural Analysis of Major Surface Proteins Hemagglutinin and Neuraminidase of Novel Avian Influenza Virus A H7N9 from Chinese Patient

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Chemical Research in Chinese Universities 2013年第5期29卷 934-940页

作者： YUAN Xiao-hui WANG Ying-chen QU Zha.g-yi REN jia-yi WU Xiao-min WANG Jing-fei Department of Microbiology Public Health College Harbin Medical University Harbin 150081 P. R. China Institute of Pathogen Biology Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100176 P R. China Key Laboratory of Resource and Plant Biology of Anhui Province College of Life Science Huaibei Normal University Huaibei 235000 P. R. China ha.bin Veterinary Research Institute Chinese Academy of Agricultural Sciences Harbin 150081 P R. China

This research reveals the phylogenetic history and structural information of the hemagglutinin（ha. and neuraminidase（NA） from novel avian influenza virus A/ha.gzhou/1/2013（HTN9_2013） strain from human infected in China. Strains closely related to the HTN9 2013 strain were obtained from Nation Center for Biotechnology Information（USA）-basic local alignment search tool（NCBI-BLAST） searching, and the phylogenetic trees were con- structed. The 3D structures of ha.and NA from H7N9 2013 strain were built by homology modeling technology, and molecular dynamics（MD） simulations were performed on the high-performance computer cluster. Cha.acteristic amino acid sites were then screened from multiple sequence alignment（MSA） via home-made Python script and mapped onto the 3D structures. The thermodynamic cha.acteristic root-mean-square-fluctuation （RMSF） of these sites in the structure was also analyzed with MD trajectories. The ha.of HTN9_2013 strain is closely related to the A/duck/Zhejiang/12/2011 strain isolated in China, while the NA of HTN9 2013 strain is mostly related to the A/mallard/Czech Republic/13438-29K/2010 strain isolated in Europe. The 3D structures of ha.and NA from H7N9 2013 stain are mostly identical to the existing structure of H7 and N9. A total of 11 and 14 cha.acteristic ami- no acid sites were identified in ha.and NA, respectively, in HTN9_2013. Structural analysis indicates tha. certain sites in the top region of ha.are important, at which the mutation of some amino acids can impact the receptor bin- ding tha. may be related to its infection of human beings.

关键词： Avian influenza virus Hemagglutinin Neuraminidase Homology modeling Phylogenetic

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基于抗非线性SVM的几何整形可见光通信系统

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应用科学学报 2020年第4期38卷 647-658页

作者：迟楠牛文清贾俊连哈依那尔复旦大学电磁波信息科学教育部重点实验室上海200433

非线性效应限制是高速可见光通信系统性能提升的一大瓶颈问题,为此提出将支持向量机(support vector machine, SVM)监督学习算法应用于几何整形可见光通信系统接收信号星座点的分类判决,将信号的同向分量和正交分量作为特征向量,建立最... 详细信息

非线性效应限制是高速可见光通信系统性能提升的一大瓶颈问题,为此提出将支持向量机(support vector machine, SVM)监督学习算法应用于几何整形可见光通信系统接收信号星座点的分类判决,将信号的同向分量和正交分量作为特征向量,建立最优分类界面,以降低非线性条件下星座点变形带来的符号误判,同时比较几种几何整形设计的性能.仿真分析和实验结果表明,SVM提升了非线性条件下系统的性能,在数据速率为1.2 Gbit/s的高速可见光通信传输中,圆-169几何整形16正交幅度调制(quadrature amplitude modulation,QAM)的符号误码性能最优.

关键词：可见光通信支持向量机几何整形抗非线性

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High-pressure capacity expansion and water injection mecha.ism and indicator curve model for fractured-vuggy carbonate reservoirs

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Petroleum 2024年第3期10卷 511-519页

作者： Lixin Chen Chengzao jia Rujie Zha.g Ping Yue Xujian jiang Junfang Wang Zhou Su Yun Xiao Yuan Lv Institute of Unconventional Oil and Gas Science and Technology China University of Petroleum(Beijing)Beijing102249China State Key Laboratory of Reservoir Geology and Development Southwest Petroleum UniversityChengdu610500China Tarim Oilfield Company PetroChinaKorla841000China

Water injection for oil displacement is one of the most effective ways to develop fractured-vuggy carbonate *** the increase in the number of rounds of water injection,the development effect gradually *** emergence of high-pressure capacity expansion and water injection technology allows increased production from old *** high-pressure capacity expansion and water injection technology ha. been implemented in practice for nearly 10 years in fractured-vuggy reservoirs,its mecha.ism remains unclear,and the water injection curve is not *** the past,evaluating its effect could only be done by measuring the injection-production *** this study,we analyze the mecha.ism of high-pressure capacity expansion and water *** propose a fluid excha.ge index for high-pressure capacity expansion and water injection and establish a discrete model suitable for high-pressure capacity expansion and water injection curves in fractured-vuggy *** propose the following mecha.isms:replenishing energy,increasing energy,replacing energy,and releasing *** above mecha.isms can be identified by the high-pressure capacity expansion and water injection curve of the well ha.X in the ha.aha.ang Oilfield in the Tarim *** solving the basic model,the relative errors of Reservoirs I and II are found to be 1.9%and 1.5%,respectively,and the application of field examples demonstrates tha. our proposed high-pressure capacity expansion and water injection indicator curve is reasonable and *** research can provide theoretical support for high-pressure capacity expansion and water injection technology in fracture-vuggy carbonate reservoirs.

关键词： Fractured-vuggy carbonate reservoirs High-pressure capacity expansion and water injection Mecha.ism Water injection indicator curve

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Effects of mecha.ized deep placement of nitrogen fertilizer rate and type on rice yield and nitrogen use efficiency in Chuanxi Plain, China

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Journal of Integrative Agriculture 2021年第2期20卷 581-592页

作者： ZHU Cong-hua OUYANG Yu-yuan DIAO You YU Jun-qi LUO Xi ZHENG jia-guo LI Xu-yi Crop Research Institute Sichuan Academy of Agricultural SciencesChengdu 610066P.R.China Sichuan Province Key Laboratory of Crop Ecophysiology and Cultivation Chengdu 611130P.R.China

This paper investigates the yield and nitrogen use efficiency (NUE) of machine-transplanted rice cultivated using mecha.ized deep placement of N fertilizer in the rice–wheat rotation region of Chuanxi Plain,*** provides theoretical support for N-saving and improves quality and production efficiency of machine-transplanted *** a single-factor complete randomized block design in field experiments in 2018 and 2019,seven N-fertilization treatments were applied,with the fertilizer being surface broadcast and/or mecha.ically placed beside the seedlings at (5.5±0.5) cm soil depth when *** treatments were:N0,no N fertilizer;U1,180 kg N ha.(–1) as urea,surface broadcast manually before transplanting;U2,108 kg N ha.(–1) as urea,surface broadcast manually before transplanting,and 72 kg N ha.(–1) as urea surface broadcast manually on the 10th d after transplanting,which is not only the local common fertilization method,but also the reference treatment;UD,180 kg N ha.(–1) as urea,mecha.ically deep-placed when transplanting;M1,81.6 kg N ha.(–1) as urea and 38.4 kg N ha.(–1) as controlled-release urea (CRU),mecha.ically deep-placed when transplanting;M2,102 kg N ha.(–1) as urea and48 kg N ha.(–1) as CRU,mecha.ically deep-placed when transplanting;M3,122.4 kg N ha.(–1) as urea and 57.6 kg N ha.(–1) as CRU,mecha.ically deep-placed when *** effects of the N fertilizer treatments on rice yield and NUE were consistent in the 2 *** a N application rate of 180 kg ha.(–1),compared with U2,the N recovery efficiency (NRE),N agronomic use efficiency (NAE) and yield under the UD treatment were 20.6,3.5 and 1.1% higher in 2018,and 4.6,1.7 and 1.2% higher in 2019,*** with urea alone (U1,U2 or UD),the NRE,NAE and yield achieved by M3 (combined application of urea and controlled-release urea) were higher by 9.2–73.3%,18.6–61.5% and 6.5–16.5%(2018),and 22.2–65.2%,25.6–75.0% and 5.9–13.9%(2019),*** with M3,the lower-N t

关键词： rice N-fertilization rate controlled release urea side deep fertilization yield nitrogen use efficiency

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