检索结果-南通市图书馆

Chinese Science Bulletin 2012年第27期57卷 3573-3577页

作者： sa wenjun AN LiZhe sa Wei Institute of Botany Science School of Life SciencesLanzhou UniversityLanzhou 730000China School of Life Science Qinghai UniversityXining 810008China

The grassland is an important component of terrestrial ecosystems and plays a significant role in biodiversity and ecosystem *** the present study,the changes of plant species diversity and aboveground biomass productivity were examined along with the altitude in natural alpine grassland in the source region of three rivers on the Qinghai-Tibetan *** experimental locations were selected with altitudes ranging from 3862 to 4450 m above sea level(a.s.l.).The results indicated that Kobresia pygmaea meadow,Kobresia humilis meadow and salix cupularis shrub meadow had higher indices of diversity and aboveground *** distribution of species diversity,richness and aboveground biomass showed similarly unimodal patterns across the altitude gradient with the highest indices appeared at mid-altitudes *** changing trend of species diversity,richness and evenness also showed significant unimodal patterns with total aboveground biomass,and the highest species diversity occurred at intermediate level of *** research would provide a valuable reference for the protection of grassland biodiversity and maintaining of the grazing ecosystem function in the source region of the Three Rivers.

关键词：植物群落多样性地上生物量海拔高度高寒草甸三江源地区植物物种多样性生态系统功能生物多样性

基于RS和GIS的西宁市LUCC分析及模拟预测

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农业工程学报 2009年第7期25卷 211-218页

作者：伏洋肖建设校瑞香洒文君李希来青海省气象科学研究所西宁810001 青海省农牧厅外事外经办西宁810008 青海大学农牧学院草业科学系西宁810003

通过研究位于青藏高原东部边缘西宁市土地利用/覆被变化(LUCC)空间转化规律,以期揭示在人类活动加剧的大背景下,实施生态建设对城市与农村及其农牧业土地利用格局、生态环境效应、社会经济状况等产生的驱动机制。运用RS与GIS综合技术,... 详细信息

通过研究位于青藏高原东部边缘西宁市土地利用/覆被变化(LUCC)空间转化规律,以期揭示在人类活动加剧的大背景下,实施生态建设对城市与农村及其农牧业土地利用格局、生态环境效应、社会经济状况等产生的驱动机制。运用RS与GIS综合技术,通过精确解译西宁市1999年与2005年两期Landsat TM遥感影像,获取了较高精度的土地利用/覆被的定量统计及矢量图,结合动态指标分析了LUCC特征;并采用地图代数运算法求得各土地利用类型的Markov转移矩阵。结果表明:1999-2005年西宁市的耕地、草地和未利用土地是LUCC的核心类型,共有占研究区域总面积73.58%的土地利用方式发生了变化,表现为一种突变性质;6a间,西宁市的河流、湖泊、湿地、草地和林地等面积显著增加,充分表明自2000年以来实施的生态建设极大地改善了西宁市的生态环境。在目前外界驱动力不变的条件下,通过Markov过程模拟与预测,未来10a以及至终级稳定状态下,西宁市的耕地面积将继续减少,建筑和交通等建设用地持续增加;林地和草地,以及河流和湖泊等湿地所占面积比例的增加,将产生良好的生态环境效应。

关键词： LUCC RS GIS 生态 Markov过程生态建设效果评价模拟与预测西宁市

Involvement of CsWRKY70 in salicylic acid-induced citrus fruit resistance against Penicillium digitatum

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Horticulture Research 2020年第1期7卷 781-792页

作者： Bing Deng wenjun Wang Changqing Ruan Lili Deng Shixiang Yao Kaifang Zeng College of Food Science Southwest University400715 ChongqingChina Research Center of Food Storage&Logistics Southwest University400715 ChongqingChina

Penicillium digitatum causes serious losses in postharvest citrus *** salicylic acid(sa)can induce fruit resistance against various pathogens,but the mechanism remains ***,a transcriptome-based approach was used to investigate the underlying mechanism of sa-induced citrus fruit resistance against *** found that CsWRKY70 and genes related to methyl salicylate(Mesa)biosynthesis(salicylate carboxymethyltransferase,saMT)were induced by exogenous ***,significant Mesa accumulation was detected in the sa-treated citrus *** potential involvement of CsWRKY70 in regulating CssaMT expression in citrus fruit was *** localization,dual luciferase,and electrophoretic mobility shift assays and an analysis of transient expression in fruit peel revealed that the nucleus‐localized transcriptional activator CsWRKY70 can activate the CssaMT promoter by recognizing the W-box *** together,the findings from this study offer new insights into the transcriptional regulatory mechanism of exogenous sa-induced disease resistance in Citrus sinensis fruit.

关键词： citrus resistance digit

Molten salt assisted fabrication of Fe@Fe_(sa)-N-C oxygen electrocatalyst for high performance Zn-air battery

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Journal of Energy Chemistry 2021年第10期30卷 612-621,I0016页

作者： wenjun Zhang Kaicai Fan Cheng-Hao Chuang Porun Liu Jian Zhao Dongchen Qi Lingbo Zong Lei Wang Taishan Scholar Advantage and Characteristic Discipline Team of Eco Chemical Process and Technology Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life ScienceMOEState Key Laboratory of Eco-chemical EngineeringCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042ShandongChina Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-PlasticsQingdao University of Science and TechnologyQingdao 266042ShandongChina Centre for Clean Environment and Energy School of Environment and ScienceGriffith UniversityQueensland 4222Australia Department of Physics Tamkang UniversityTamsui 251New Taipei City 251301TaiwanChina School of Chemistry and Physics Centre for Materials ScienceQueensland University of TechnologyBrisbaneQueensland 4001Australia

Non-noble-metal-based electrocatalysts with superior oxygen reduction reaction(ORR)activity to platinum(Pt)are highly desirable but their fabrications are challenging and thus impeding their applications in metal-air batteries and fuel ***,we report a facile molten salt assisted two-step pyrolysis strategy to construct carbon nanosheets matrix with uniformly dispersed Fe_(3) N/Fe nanoparticles and abundant nitrogen-coordinated Fe single atom moieties(Fe@Fe_(sa)-N-C).Thermal exfoliation and etching effect of molten salt contribute to the formation of carbon nanosheets with high porosity,large surface area and abundant uniformly immobilized active ***-corrected high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM)image,X-ray absorption fine spectroscopy,and X-ray photoelectron spectroscopy indicate the generation of Fe(mainly Fe_(3) N/Fe)and Fe_(sa)-N-C moieties,which account for the catalytic activity for *** study on modulating the crystal structure and composition of Fe_(3) N/Fe nanoparticles reveals that proper chemical environment of Fe in Fe_(3) N/Fe notably optimizes the ORR ***,the presence of abundant Fe_(sa)-N-C moieties,and potential synergies of Fe_(3) N/Fe nanoparticles and carbon shells,markedly promote the reaction *** as-developed Fe@Fe_(sa)-N-C-900 electrocatalyst displays superior ORR performance with a half-wave potential(E_(1/2))of 0.83 V versus reversible hydrogen electrode(RHE)and a diffusion limited current density of 5.6 mA cm^(-2).In addition,a rechargeable Zn-air battery device assembled by the Fe@Fe_(sa)-N-C-900 possesses remarkably stable performance with a small voltage gap without obvious voltage loss after500 h of *** facile synthesis strategy for the high-performance composites represents another viable avenue to stable and low-cost electrocatalysts for ORR catalysis.

关键词： Molten salt Oxygen reduction reaction Long-term durability Zn-air batteries

Development of PREDAC-H1pdm to model the antigenic evolution of influenza A/(H1N1)pdm09 viruses

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Virologica Sinica 2023年第4期38卷 541-548页

作者： Mi Liu Jingze Liu wenjun Song Yousong Peng Xiao Ding Lizong Deng Taijiao Jiang Jiangsu Institute of Clinical Immunology The First Affiliated Hospital of Soochow UniversitySuzhou215006China Institute of Systems Medicine Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing100005China Suzhou Institute of Systems Medicine Suzhou215123China Guangzhou Laboratory Guangzhou510005China Bioinformatics Center College of BiologyHunan Provincial Key Laboratory of Medical VirologyHunan UniversityChangsha410082China State Key Laboratory of Respiratory Disease the First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou Medical UniversityGuangzhou510120China

The Influenza A(H1N1)pdm09 virus caused a global pandemic in 2009 and has circulated seasonally ever *** the continual genetic evolution of hemagglutinin in this virus leads to antigenic drift,rapid identification of antigenic variants and characterization of the antigenic evolution are *** this study,we developed PREDAC-H1pdm,a model to predict antigenic relationships between H1N1pdm viruses and identify antigenic clusters for post-2009 pandemic H1N1 *** model performed well in predicting antigenic variants,which was helpful in influenza *** mapping the antigenic clusters for H1N1pdm,we found that substitutions on the sa epitope were common for H1N1pdm,whereas for the former seasonal H1N1,substitutions on the Sb epitope were more common in antigenic ***,the localized epidemic pattern of H1N1pdm was more obvious than that of the former seasonal H1N1,which could make vaccine recommendation more ***,the antigenic relationship prediction model we developed provides a rapid determination method for identifying antigenic variants,and the further analysis of evolutionary and epidemic characteristics can facilitate vaccine recommendations and influenza surveillance for H1N1pdm.

关键词： H1N1pdm virus Antigenic relationship prediction Antigenic evolution Vaccine recommendation

Q-switched fiber laser operating at 1.5 μm based on WTe_2

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Chinese Optics Letters 2019年第2期17卷 25-28页

作者： Mengli Liu Yuyi Ouyang Huanran Hou wenjun Liu Zhiyi Wei State Key Laboratory of Information Photonics and Optical Communications School of Science Beijing University of Posts and Telecommunications Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences

Compared with the extensively studied MoS2 and WS2, WTe_2 owns a smaller bandgap, which is applicable to a near-infrared system in photodetectors, communications, and ultrafast optics. In this work, the WTe_2 saturable absorber(sa) with the tapered fiber structure is prepared by the magnetron-sputtering technology, which enables the prepared sa to be low in cost and have strong nonlinearity. The modulation depth of the prepared WTe_2 sa is measured as 31.06%. The Q-switched fiber laser operating at 1.5 μm is successfully investigated by incorporating the proposed sa into the prepared ring cavity. To the best of our knowledge, this is the first attempt of WTe_2 in the Q-switched fiber laser at 1.5 μm.

关键词： Q-switched laser operating

Highly dispersed atomic-level Ni active sites confined in defects for efficient electrocatalytic reduction of carbon dioxide

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Journal of Energy Chemistry 2024年第12期99卷 1-10页

作者： wenjun Zhang Chen Zhao Yang Yang Ruotong Chen Yue Wu Jiaqi Dai Yuxing Zhang Huajie Liu Mingyang Liu College of Environmental Science and Engineering State Key Laboratory of Medicinal Chemical BiologyNankai UniversityTianjin 300350China School of Chemical Science and Engineering Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education and Shanghai Research Institute for Intelligent Autonomous SystemsTongji UniversityShanghai200092China

Electrocatalytic CO_(2) reduction reaction (eCO_(2)RR) presents a promising approach for harnessing renewable energy and converting greenhouse gas (CO_(2)) into high value-added CO products.N-doped single atom (sa) and atomic-level metal nanocluster (MN) tandem catalysts with rich defects for eCO_(2)RR are reported,which achieved a maximum CO Faraday efficiency (FE_(CO)) of 97.7%(-0.7 V ***) in the H-type cell and maintained over 95% FE_(CO)at potentials from -0.18 to -0.73 V *** in the flow ***,the catalyst in the flow cell demonstrated a remarkably low onset potential of-0.14 V *** and the current density was approximately three times that of the H-type ***,XPS analysis indicates that carbon substrates containing defects have more pyridine-N *** calculations and in-situ attenuated total reflection Fourier transform infrared support this finding by showing that the Ni-(N-C_(2))_(3) active sites with defect favors preferentially convert CO_(2)-to-CO.

关键词： Electrocatalytic CO_(2)RR Atomic-level nanoclusters Defects Catalytic mechanism

TRANSIENT EM FIELDS IN DISPERSIVE MEDIA BY FDTD METHOD

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TRANSIENT EM FIELDS IN DISPERSIVE MEDIA BY FDTD METHOD

Characteristics of rural domestic sewage discharge and their driving mechanisms: evidence from the Northern Region, China

1993 International Symposium on Radio Propagation(ISRP’93)

作者： wenjun,Zhang Shanghai University of Technology

＜正＞The traditional finite-difference in time-domain（FDTD） has applied widely,but it requires that the permittivity and conductivity be specified sa frequency independent,which is a serious limitation for solving the transient EM problem of dispersive materials.A modified finite-difference in time domain（FDTD） method for frequency dependent problem is presented in this paper,using Prony’s approximation the time-domain convolution can be calculated recursively,and the transient EM problem in dipersive media can be solved easily,the results that are obtained from this way are reliable,and provided a new efficient direct way to study characteristics of transient EM interaction and wide-band EM problems of dispersive materials.

关键词：

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Frontiers of Environmental Science & Engineering 2024年第7期18卷 47-58页

作者： Jianguo Liu Ziyu Zhou Pengyu Li Zixuan Wang Ying Yan Xuezheng Yu Wenkai Li Tianlong Zheng Yingnan Cao wenjun Wu Wenqian Cai Zhining Shi Junxin Liu Key Laboratory of Environmental Pollution Control and Remediation at Universities of Inner Mongolia Autonomous Region College of Resources and Environmental EngineeringInner Mongolia University of TechnologyHohhot 010051China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China SCEGC No.12 Construction Engineering Group Co. Ltd.Ankang 725000China State Environmental Protection Key Laboratory of Environmental Planning and Policy Simulation Chinese Academy of Environmental PlanningBeijing 100041China Technical Centre for Soil Agriculture and Rural Ecology and EnvironmentMinistry of Ecology and EnvironmentBeijing 100012China Sustainable Infrastructure and Resource Management(SIRM) UniSA STEMUniversity of South AustraliaSouth AustraliaMawson LakesSA 5095Australia

The traits of rural domestic sewage emission are unclear,negatively affecting rural domestic sewage treatment and sewage *** study used data from the Second National Pollution Source Census Bulletin to establish a data *** spatial distribution characteristics and main factors influencing rural sewage discharge in the Northern Region were studied using spatial autocorrelation analysis and structural *** findings demonstrated that(l)a significant Spearman correlation between drainage water volume(DwV),chemical oxygen demand(COD),ammonia nitrogen(NH_(3)-N),total nitrogen(TN),and total phosphorus(TP)and that the correlation coefficients between DWV and COD,NH,-N,TNand TP were 0.87**,1.0**,0.99**,0.99**,respectively;(2)rural sewage discharge showed spatial autocorrelation,and rural domestic sewage discharge in the districts and counties with an administration was significantly higher than in the surrounding areas;and(3)social development was the main driver rural domestic sewage changes(path coefficient was 0.407**),and the main factors influencing rural domestic sewage discharge were the urbanization rate,years of education,and population age *** study obtained the spatial variation law and clarified the main influencing factors of rural domestic sewage to provide data support and a theoretical basis for subsequent rural sewage collection and *** of the Inner Mongolia Autonomous Region in northern China as a typical case,provides a theoretical foundation for scientific decision-making on rural domestic sewage treatment at the national and regional levels and offers new perspectives for managing pollutants.

关键词： Rural domestic sewage Emission characteristics Spatial autocorrelation analysis Influencing factors

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GTG起爆药在工业雷管中的应用

爆破器材 2001年第1期30卷 15-19页

作者：撒光曹文俊叔宝源北京矿务局化工厂北京102471 北京燕麓通科技开发有限公司北京102471

文章对 GTG起爆药在工业雷管中的应用进行了研究 ,找到了合理的工艺技术条件 ,并对研制的系列雷管按标准要求进行了测试 ,同时对 GTG起爆药在雷管中应用的经济性进行了分析和比较。

关键词： GTG起爆管工业雷管工艺条件经济性应用