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地方政府环境管理体制分析

教学与研究 2009年第1期 34-39页

作者：曾贤刚中国人民大学环境学院北京100872

我国的环境管理存在很多体制问题:一方面,经济管理部门与环保管理部门相互分隔,经济部门在实际决策中很少考虑环境问题;另一方面,环保部门在复杂的权力配置与利益分配中难以作为。地方政府在平衡环境保护与经济发展时通常体现为复杂的... 详细信息

我国的环境管理存在很多体制问题:一方面,经济管理部门与环保管理部门相互分隔,经济部门在实际决策中很少考虑环境问题;另一方面,环保部门在复杂的权力配置与利益分配中难以作为。地方政府在平衡环境保护与经济发展时通常体现为复杂的组织行为,如环境污染的机会主义,其背后所反映的是利益竞争和外部不经济性。

关键词：地方政府环境管理体制问题

Analysis of the function of D279N mutation of VP2 of infectious bursal disease virus

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Journal of Integrative Agriculture 2015年第12期14卷 2618-2625页

作者： QI Xiao-le LU Zhen WANG Nian CHEN Yu-ming ZHANG Li-zhou GAO Li LI Kai REN xian-gang WANG Yong-qiang GAO Hong-lei GAO Yu-long Nicolas Eterradossi WANG Xiao-mei Division of Avian Infectious Diseases State Key Laboratory of Veterinary Biotechnology Harbin Veterinary Research Institute Chinese Academy of Agricultural Sciences Avian and Rabbit Virology Immunology and Parasitology Unit OIE Reference Laboratory for Infectious Bursal Disease French Agency for Food Environmental and Occupational Health Safety (Anses) Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Disease and Zoonoses

Infectious bursal disease virus（IBDV）is responsible for the highly contagious infectious bursal disease of *** understanding the gene-function is necessary to design the tailored *** amino acid residue 279,located on strand P_F of VP2,is one of the three residues that have been reported to be involved in cell-tropism but with some *** this study,to further clarify the amino acids involved in the cell tropism of IBDV,a series of mutations about residue 279were introduced into the VP2 of vv IBDV Gx *** the reverse genetic system,we found single mutation of D279N,double mutations of D279N/A284T or Q253H/D279N were not enough to adapt IBDV to chicken embryo fibroblast（CEF）*** evaluate whether residue 279 could influence the replication and virulence of IBDV,the virus r Gx HT-279 with three mutations（Q253H/D279N/A284T）was rescued and *** showed that the mutation of residue 279 in VP2had no efficient effects on both the replication efficiency in vitro and the virulence to SPF chickens of *** summary,the results demonstrated that residue 279 of VP2 did not contribute efficiently to cell tropism,replication efficiency,and virulence of IBDV at least in some *** findings provided further information for understanding the gene function of IBDV.

关键词： infectious bursal disease virus(IBDV) residue 279 cell tropism virulence

Recent Advances in Microbial Production of Terpenoids from Biomass-derived Feedstocks

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Chemical Research in Chinese Universities 2024年第1期40卷 20-28页

作者： CAO Yujin xian Mo CAS Key Laboratory of Biobased Materials Qingdao Institute of BioEnergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101P.R.China Shandong Energy Institute Qingdao 266101P.R.China Qingdao New Energy Shandong Laboratory Qingdao 266101P.R.China

Terpenoids are a diverse class of natural products widely used as pharmaceuticals,perfumes,flavors,and ***,terpenoids are obtained from natural sources,such as plants,but their production is limited by the insufficiency of resources and low yields of *** production of terpenoids has emerged as a promising alternative due to that it is sustainable and easy to scale *** review aims to summarize recent advances in microbial production of terpenoids from inexpensive biomass-derived *** pathways and key enzymes involved in terpenoid biosynthesis are *** that can utilize low-cost lignocellulosic feedstocks for terpenoid production are *** challenges and prospects faced by microbial terpenoid production are *** believe that continuous progress in the fields of biomass transformation and synthetic biology will ultimately achieve industrial production of microbial terpenoids.

关键词： Terpenoid Microbial production Biomass-derived feedstock Metabolic pathway

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中国区域环境效率及其影响因素

经济理论与经济管理 2011年第10期31卷 103-110页

作者：曾贤刚中国人民大学环境学院北京100872

本文基于DEA方法运用2000—2008年省级面板数据计算了我国30个省市的环境效率,同时使用Tobit模型分析了该环境效率的影响因素。研究表明:(1)2000—2008年,中国30个省区的环境效率基本保持在0.7～1之间波动,各省区平均环境效率刚开始时... 详细信息

本文基于DEA方法运用2000—2008年省级面板数据计算了我国30个省市的环境效率,同时使用Tobit模型分析了该环境效率的影响因素。研究表明:(1)2000—2008年,中国30个省区的环境效率基本保持在0.7～1之间波动,各省区平均环境效率刚开始时呈下降趋势,但在2004年或2005年出现明显拐点。(2)我国环境效率地区差异明显,东部发达地区在效率水平上优于中西部地区,中西部地区环境效率的敏感性高。另外,2005年以来西部与东部的效率差距趋于缩小,而中部的情况则不乐观。(3)加大对从业人员、能源、用水等投入要素的利用程度,能有效提高环境效率。(4)经济水平、外贸依存度、人口密度都会对我国环境效率产生显著的正面影响,其中人均GDP和进出口贸易额对环境效率影响较大,而工业污染治理投资占GDP比重对环境效率影响不显著。

关键词： DEA 环境效率 Tobit模型

Classification of knowledge graph completeness measurement techniques

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Journal of Systems Engineering and Electronics 2024年第1期35卷 154-162页

作者： ZHANG Ying XIAO gang Institute of Systems Engineering Academy of Military SciencesBeijing 100107China

At present,although knowledge graphs have been widely used in various fields such as recommendation systems,question and answer systems,and intelligent search,there are always quality problems such as knowledge omissions and *** assessment and control,as an important means to ensure the quality of knowledge,can make the applications based on knowledge graphs more complete and more accurate by reasonably assessing the knowledge graphs and fixing and improving the quality problems at the same ***,as an indispensable part of the knowledge graph construction process,the results of quality assessment and control determine the usefulness of the knowledge *** them,the assessment and enhancement of completeness,as an important part of the assessment and control phase,determine whether the knowledge graph can fully reflect objective phenomena and reveal potential connections among *** this paper,we review specific techniques of completeness assessment and classify completeness assessment techniques in terms of closed world assumptions,open world assumptions,and partial completeness *** purpose of this paper is to further promote the development of knowledge graph quality control and to lay the foundation for subsequent research on the completeness assessment of knowledge graphs by reviewing and classifying completeness assessment techniques.

关键词： quality assessment completeness assessment closed world assumptions open world assumption partial completeness assumption

LSPR spectral properties of Au nano-ring arrays and single Au nanoparticles

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中国光学与应用光学 2010年第1期3卷 75-78页

作者： MA Jun-xian TAN Rui-hu FANG Yu ZHENG Da-wei LUO xian-gang Advanced Technology Research Center Shenzhen University Shenzhen 518050 China

In this paper, we simulate Localized Surface Plasmon Resonance(LSPR) absorption of periodic Au nano-ring arrays and single Au nanoparticles using the Finite Difference Time Domain(FDTD) method. We choose input plane waves of different wavelengths and discuss the relation between the absorption peak of the Au array and the variable external dielectric constants. It is found that the sensitivity of these sensors based on LSPR is improved compared to the common sensors and the enhancement is caused by the periodical structure. We also investigate the spectrum characteristic of a single Au nanoparticle and discuss the relation between the absorption peak and the size of the nanoparticle.

关键词：等离子体平面波周期性结构共振

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西北酸菜高效复合发酵菌种的筛选

食品科学 2011年第11期32卷 222-227页

作者：孟宪刚唐璎兰州交通大学化学与生物工程学院甘肃兰州730070

从西北酸菜中分离出53株菌株,对其进行单因素接种发酵、分子鉴定、生理生化、适温与低温产酸速度、降解亚硝酸盐能力测定后,筛选出在产酸速度快的AC-5、醇香味适中的Y7、降解亚硝酸达78.17%的L5、发酵风味接受度最高的L8这4种菌株,为西... 详细信息

从西北酸菜中分离出53株菌株,对其进行单因素接种发酵、分子鉴定、生理生化、适温与低温产酸速度、降解亚硝酸盐能力测定后,筛选出在产酸速度快的AC-5、醇香味适中的Y7、降解亚硝酸达78.17%的L5、发酵风味接受度最高的L8这4种菌株,为西北酸菜提供高效发酵菌株。

关键词：西北酸菜直投式发酵剂(DVS) 复合菌剂分离鉴定发酵性能亚硝酸盐

Basic properties of trapezoidal channel plasmon polariton subwavelength waveguides

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中国光学与应用光学 2010年第1期3卷 89-92页

作者： MA Jun-xian FANG Yu CHEN Bi-bo TAN Rui-hu LUO xian-gang Advanced Technology Research Center Shenzhen university Shenzhen 518060 China

An air channel inside a silver metal film is usually used as a typical Channel Plasmon Polariton(CPP) waveguide. This paper presents research on the basic properties of this waveguide using the Finite Difference Time Domain(FDTD) method. The relationship between transmission power and structure of the waveguide is investigated. The simulation results show that the subwavelength trapezoidal CPP waveguide is superior to the rectangle CPP waveguide for controlling SPP radiation loss and enhancing the transmitted power. As a result, if the rectangle CPP waveguide is replaced by a trapezoidal CPP waveguide in certain integrated optical devices, their performance may be improved.

关键词：金属薄膜发射功率波导技术光学器件

堰塞坝溃口斜坡失稳概率分布函数参数确定及影响因素分析

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兰州理工大学学报 2018年第1期44卷 121-127页

作者：蒋先刚四川农业大学土术工程学院四川都江堰611830 中国科学院成都山地灾害与环境研究所山地灾害与地表过程重点实验室四川成都610041

为确定堰塞坝溃口斜坡在水流侵蚀作用下的失稳概率分布函数,掌握函数变化规律,明确不同因素对稳定性影响强弱程度,开展了数值分析.结果表明:随着侵蚀发展,平均主应力逐渐减小,剪应力逐渐增大,处于破坏面上的剪应力到达峰值点后逐渐减小... 详细信息

为确定堰塞坝溃口斜坡在水流侵蚀作用下的失稳概率分布函数,掌握函数变化规律,明确不同因素对稳定性影响强弱程度,开展了数值分析.结果表明:随着侵蚀发展,平均主应力逐渐减小,剪应力逐渐增大,处于破坏面上的剪应力到达峰值点后逐渐减小.概率密度分布函数中参数a随溃口高度和斜坡坡度的增大先增大后减小,随侵蚀深宽比的增大先增大后趋于稳定.随着斜坡坡高的增大,安全系数对小坡高较敏感,斜坡坡度和容重影响下的安全系数具有相同的规律.随着黏聚力的增大,安全系数对小黏聚力较敏感,当黏聚力增大到一定程度,黏聚力的变化对安全系数的变化不敏感.安全系数关于内摩擦角的灵敏度随内摩擦角的增大先减小后增大,侵蚀深宽比对安全系数的影响具有相同规律.

关键词：堰塞坝溃口斜坡侵蚀概率敏感度