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Journal of Integrative Agriculture 2020年第12期19卷 2891-2902页

作者： ZHUO ni JI chen DING Jing-yu china Academy for Rural Development(CARD)and Department of Agricultural Economics and Management School of Public AffairsZhejiang UniversityHangzhou 310058P.R.China

Pig farmers’willingness to recover production under the COVID-19 pandemic shock is significant to recover live pigs’supply in china in *** farmers’willingness to recover pig production contributes to enhance pig supply,stabilize the pig and pork market,and to improve pig farmers’*** research studies the determinants of pig farmers’willingness to recover production under COVID-19 pandemic shock by applying survey data of 201 farmers in Huai’an City and Lin’an City and a logit regression *** estimation results show that a farmer’s risk perception,the duration time of a farmer’s feed supply under COVID-19 pandemic shock,whether or not being a cooperative member,and a farmer’s knowledge on government’s policy designed to encourage pig production,a farmer’s education level and production experience are the key determinants to a farmer’s willingness to recover pig ***,it’s important for policymakers to solve the problems for farmers to get access to feed during the pandemic,to encourage the development of cooperatives,as well as to issue and advocate policies to encourage pig *** study contributes to the scant literature by providing fresh empirical evidences on determinants of farmers’willingness to recover pig *** has significance to farmers and governments to enhance farmers’willingness to recover production,which contributes to secure pig supply in china after the COVID-19 pandemic.

关键词： farmers&rsquo willingness to recover production COVID-19 pandemic shock pig industry in china

Response mechanism of soil microorganisms to simulated precipitation in the source wetland of Qinghai Lake

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Ecological Processes 2024年第2期13卷 61-71页

作者： Xinye Wang ni Zhang Kelong chen Tiexi chen Desheng Qi Yuanxi Ma School of Geographical Sciences Qinghai Normal University National Positioning Observation and Research Station of Qinghai Lake Wetland Ecosystem in Qinghai National Forestry and Grassland Administration Key Laboratory of Tibetan Plateau Land Surface Processes and Ecological Conservation(Ministry of Education) Qinghai Normal University School of Geographical Sciences Nanjing University of Information Science and Technology Qinghai Provincial land spatial Planning Research Institute

Background Changes in precipitation patterns crucially impact soil microbial communities, and the ecosystem in Qinghai-Tibet Plateau(QTP) is highly vulnerable to climate change. However, we do not fully understand how soil microbial communities in the source wetlands of QTP respond to changes in precipitation. In this study, we employed advanced techniques such as high-throughput sequencing and metabolomics to investigate how soil microbial communities in a source wetland of Qinghai Lake respond to changes in precipitation after quadrennial precipitation *** Our findings showed that the predominant microbiota in the source wetland was Proteobacteria. Interestingly, alterations in precipitation levels, whether increased or reduced, did not significantly impact the diversity or functional groups of the microbial community. However, the structure of the microbial community did respond notably to changes in precipitation, leading to shifts in the relative abundance of Spirochaetes and Treponema. A notable finding was that reduced precipitation levels(– 25% and-50%) and mild increases in precipitation(25%) within the region contributed to increased soil carbon content. However, this effect ceased to manifest when precipitation increased by 50%. Additionally, the reduction in precipitation prompted the release of soil metabolites like syringic acid and aldosterone, while enhanced precipitation resulted in a decrease in aldosterone *** Precipitation changes altered the relative abundance of soil microbial communities and metabolites, which was conducive to increasing carbon storage in this alpine wetland.

关键词： Qinghai-Tibet Plateau Climate change Precipitation gradient Carbon and nitrogen cycles LC/MS

Quantum Radiative Correction on the Mass of Electron in a Cavity

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chinese Physics Letters 1997年第1期14卷 9-12页

作者： ni Guang-jiong chen Su-qing Department of Physics Fudan UniversityShanghai 200433

When an electron is moving through a cavity,its mass is modified due to the boundary effect on the virtual *** shift of self energy is calculated at the one loop level by means of Plana formula to yield analytical res... 详细信息

关键词： Electron boundary moving

Effects of Ti-and Nb-based transition element from single to multiple compound oxides and carbon-based composite additives on Mg-MgH2 hydrogen storage material

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Tungsten 2025年第1期 32-49页

作者： Li-Rong Xiao chen chen Shuo Wang Zi-Yin Dai Hideo Kimura Cui ni Chuan-Xin Hou Xue-Qin Sun Si-Jie Guo Wei Du Xiu-Bo Xie School of Environmental and Material Engineering Yantai University Bosch HUAYU Steering Systems (Yantai) Co. Ltd.Ytp/MFE University of Tennessee Knoxville Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta Shandong University of Aeronautics

MgH2is considered as a promising hydrogen storage material for its high hydrogen storage capacity,low cost and abundant resource ***,the low kinetics and high enthalpy formation of MgH2limit its wide *** the perspective of adding catalysts to enhance the hydrogen storage properties of Mg-MgH2,this article elaborated the main catalysts based on Ti and Nb transition elements,including single oxide catalysts,binary oxides catalysts（combined with ni,Na,Sr,V,etc.）,multiple catalysts bound to carbon,and composite catalysts with Ti and Nb elements combined with MXene ***,the main pathways of various catalysts to reduce the reaction activity and broaden the hydrogen desorption channel were also *** Ti-based catalysts can enhance the reactive sites of the matrix by forming multivalent states,while Nb-based catalysts broaden the hydrogen reaction channels by forming tiny *** improving the size structure and enhancing the grain size stability,combined with carbon materials should be the future considerations.

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An Assessment of Amplicon-Sequencing Based Method for Viral Intrahost Analysis

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Virologica Sinica 2018年第6期33卷 557-560页

作者： Ming ni chen chen Di Liu Beijing Institute of Radiation Medicine Beijing 100850China Institute of Infectious Diseases Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Wuhan Institute of Virology Chinese Academy of SciencesWuhan 430071China

Dear Editor,RNA virus features the high per-generation mutation rate,resulting in highly diversified population, which determines viral phenotypes and fitness (Domingo et al. 2012).The development of deep sequencing and bioinformatic techniques paves the way to study viral population genetics at an intrahost level, and has provided new insights into viral evolution.

关键词： In

SEMI－EMPIRICAL　QUANTUM　CHEMISTRY　STUDY　ON　ELECTROCHEMICAL　REDUCTION　OF　DIMETHYLGLYOXIMATOniCKEL

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chinese Chemical Letters 1996年第7期7卷 643-646页

作者： chen, MB Gao, K ni, YM chiNESE ACAD SCI INST ORGAN CHEMSHANGHAI 200032PEOPLES R CHINA TONGJI UniV DEPT CHEMSHANGHAI 200092PEOPLES R CHINA

The mechanism of the electrochemical reduction of the nickel(Ⅱ) complex dimethylglyoxime and ammonia is studied by means of INDO,energy localization and electrostatic potential methods.

关键词： SEMI EMPIRICAL DIMETHYLGLYOXIMATOniCKEL CHEMISTRY

Phase diagram,correlations,and quantum critical point in the periodic Anderson model

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chinese Physics B 2018年第3期27卷 362-367页

作者： Jian-Wei Yang Qiao-ni chen Department of Physics Beijing Normal University Beijing 100875 China

Periodic Anderson model is one of the most important models in the field of strongly correlated electrons. With the recent developed numerical method density matriX embedding theory, we study the ground state properties of the periodic Anderson model on a two-dimensional square lattice. We systematically investigate the phase diagram away from half filling. We find three different phases in this region, which are distinguished by the local moment and the spin-spin correlation functions. The phase transition between the two antiferromagnetic phases is of first order. It is the so-called Lifshitz transition accompanied by a reconstruction of the Fermi surface. As the filling is close to half filling, there is no difference between the two antiferromagnetic phases. From the results of the spin-spin correlation, we find that the Kondo singlet is formed even in the antiferromagnetic phase.

关键词： periodic Anderson model Kondo singlet states density matrix embedding theory

Effective ac Conductivity of a Suspension of Charged Particles in Electrolyte Solution by Collocation Method

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chinese Physics Letters 1995年第7期12卷 438-441页

作者： ni Fusheng GU Guoqing chen Kangmin College of Power Engineering East China University of TechnologyShanghai 200093

A collocation method is employed to study the effective ac conductivity of a suspension of charged particles in electrolyte *** method is very effective over a wide range of particle concentration and no longer restricted to the assumption made by the Rayleigh method that the two phases of a suspension have the same dielectric constants.

关键词： solution. method Conductivity

Hotel room allocation with multiple sales channels:a perspective of minimax regret

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Journal of Control and Decision 2020年第4期7卷 359-378页

作者： Guanqun ni Xin Feng Lei chen College of Management&College of Tourism Fujian Agriculture and Forestry UniversityFuzhouPeople’s Republic of China

We consider a room allocation problem for a hotel providing room reservation service through multiple *** room allocation models usually assume hotels can forecast the characteristics of demand function and/or arrival process to some *** in practice,such a restrictive assumption is possibly unrealistic,and thus the corresponding risk-neutral approaches are *** main contribution of this paper is that we formulate the hotel’s room allocation problem without any assumption on demand from the perspective of minimax regret and derive an adaptive nested limits strategy which allows higher profitable channels having access to all rooms reserved for lower profitable *** results show that customers arrive in a low-before-high manner in the worst-case *** this basis,we further prove the lower bound of maximum regret for any strategy and develop an optimal strategy matching the lower *** with other common strategies is also discussed.

关键词： Room allocation minimax regret worst-case analysis nested strategy

钼铜载体与铝合金外壳的无压纳米银胶低温烧结强度

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半导体技术 2025年第1期50卷 95-100页

作者：陈澄尹红波王成倪大海谢璐曾超林扬州海科电子科技有限公司江苏扬州225001

纳米银胶的烧结温度一般为250℃及以上,而在功率模块装配过程中,多温度梯度装配工艺要求纳米银胶的烧结温度不得超过217℃。使用800HT2V纳米银胶烧结钼铜载体与铝合金外壳,观察了不同烧结温度下纳米银胶装配后的微观形貌,测试了其装配... 详细信息

纳米银胶的烧结温度一般为250℃及以上,而在功率模块装配过程中,多温度梯度装配工艺要求纳米银胶的烧结温度不得超过217℃。使用800HT2V纳米银胶烧结钼铜载体与铝合金外壳,观察了不同烧结温度下纳米银胶装配后的微观形貌,测试了其装配后剪切强度、热导率的变化,并进行了温度冲击试验。测试结果表明,烧结样品剪切强度均符合标准要求,随着烧结温度的升高,纳米银胶热导率及剪切强度明显提升,且在最高温度200℃下烧结充分,并形成致密的烧结体。在温度冲击试验后烧结样品的剪切强度均有一定程度的下降,最高温度150℃和175℃烧结的纳米银胶烧结样品剪切强度下降超过40%,而最高温度200℃烧结的样品剪切强度只下降21.2%。考虑到功率模块的长期可靠性,纳米银胶推荐使用最高温度200℃烧结。

关键词：无压纳米银胶烧结钼铜载体铝合金外壳剪切强度热导率可靠性