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安徽省城镇化与产业结构关系的实证分析
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作者 任长娟 胡楠 《商业经济》 2014年第14期47-48,100,共3页
通过对1990-2013年安徽省城镇化与产业结构关系的研究结果表明:城镇化水平的提高能够促进产业结构升级,使产业结构更加高度化、合理化。近些年,安徽省城镇化水平大体呈现上升趋势,但三大产业产值比例分配还不合理,同时,城镇化质量不高... 通过对1990-2013年安徽省城镇化与产业结构关系的研究结果表明:城镇化水平的提高能够促进产业结构升级,使产业结构更加高度化、合理化。近些年,安徽省城镇化水平大体呈现上升趋势,但三大产业产值比例分配还不合理,同时,城镇化质量不高、资源浪费和环境污染严重、建设资金不足、总体规划不完善等问题也严重阻碍了城镇化的进一步发展。安徽省应加强基础设施建设,优先发展第三产业,并提高农村劳动力质量,加快户籍改革制度,以实现城镇化的快速健康发展,促进产业结构不断优化升级。 展开更多
关键词 安徽省 城镇与产业结构关系 实证分析
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再看准定语结构的产生机制和语义表达 被引量:4
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作者 李强 《语言科学》 CSSCI 北大核心 2020年第3期235-254,共20页
关于准定语结构的研究已经有不少成果,无论是从形式句法的角度,还是从认知功能的角度,都或多或少存在一些不好解释的问题。文章在现有研究成果的基础上再对准定语结构进行一些探讨,认为准定语结构的深层是个关系化结构形式,在经过动词... 关于准定语结构的研究已经有不少成果,无论是从形式句法的角度,还是从认知功能的角度,都或多或少存在一些不好解释的问题。文章在现有研究成果的基础上再对准定语结构进行一些探讨,认为准定语结构的深层是个关系化结构形式,在经过动词拷贝和删除之后,形成貌似表达领属语义关系的"的"字结构。准定语句和动词拷贝句虽然语义上有很紧密的联系,但还是存在差异:准定语句表现出说话人在叙述视角、情感和认识等方面的主观性特征,而动词拷贝句侧重于表现说话人对动作行为及其结果影响的客观陈述和说明。 展开更多
关键词 准定语 关系化结构 动词拷贝 主观性
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Study on Structure Evolution of Leaves of 3 Plants in Vicia 被引量:1
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作者 刘丹丹 麻莹 +4 位作者 高伟 林芳 李春娇 陈丹萍 陆静梅 《Agricultural Science & Technology》 CAS 2016年第12期2677-2681,2712,共6页
This study was conducted to compare leaf anatomical structures and ap- parent plant print characteristics of 3 Vicia plants from Changbai Mountains applying structural botany principle and fingerprint identification t... This study was conducted to compare leaf anatomical structures and ap- parent plant print characteristics of 3 Vicia plants from Changbai Mountains applying structural botany principle and fingerprint identification technology, aiming at dis- cussing the structure evolution law of Vicia plants and providing scientific reference for research about classification, genetic relationship and evolutionary trend of this genus. The comparison of leaf anatomical structures of Vicia lilacina, V. pseu- dorobus and V. unijuga showed that: V. unijuga has tidily arranged leaf epidermal cells, thickened outer tangential wall cuticle, large diameter of xylem vessels, and developed midrib fibrocytes which form vascular bundle sheaths. Plant print identifi- cation results showed that the tested 3 plants showed remarkable differences in leaf apparent texture and anticlinal wall type though plant print characteristics of appar- ent structures of plants in the same genus had homologous similarity. V. lilacina has no subsidiary cells, and apparent textures of V. pseudorobus and V. unijuga are both of paracytic unequal type. Statistical analysis showed that V. unijuga is more advanced than V. pseudorobus. The 3 tested plants are in evolutionary rela- tionship of V. lilacina〈V, pseudorobus〈V, unijuga. 展开更多
关键词 VICIA Anatomical structure Evolutionary relationship
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Choosing meaningful structure data for improving web search
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作者 郭茜 杨晓春 +1 位作者 于戈 李广翱 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期343-346,共4页
In order to improve the quality of web search,a new query expansion method by choosing meaningful structure data from a domain database is proposed.It categories attributes into three different classes,named as concep... In order to improve the quality of web search,a new query expansion method by choosing meaningful structure data from a domain database is proposed.It categories attributes into three different classes,named as concept attribute,context attribute and meaningless attribute,according to their semantic features which are document frequency features and distinguishing capability features.It also defines the semantic relevance between two attributes when they have correlations in the database.Then it proposes trie-bitmap structure and pair pointer tables to implement efficient algorithms for discovering attribute semantic feature and detecting their semantic relevances.By using semantic attributes and their semantic relevances,expansion words can be generated and embedded into a vector space model with interpolation parameters.The experiments use an IMDB movie database and real texts collections to evaluate the proposed method by comparing its performance with a classical vector space model.The results show that the proposed method can improve text search efficiently and also improve both semantic features and semantic relevances with good separation capabilities. 展开更多
关键词 WEB SEMANTIC attributes relationship structure data query expansion
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Notes on Quantitative Structure-Properties Relationships (QSPR) Part Four: Quantum Multimolecular Polyhedra, Collective Vectors, Quantum Similarity, and Quantum QSPR Fundamental Equation
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作者 Ramon Carbo-Dorca Silvia Gonzalez 《Management Studies》 2016年第1期33-47,共15页
The nature and origin of a fundamental quantum QSPR (QQSPR) equation are discussed. In principle, as any molecular structure can be associated to quantum mechanical density functions (DF), a molecular set can be r... The nature and origin of a fundamental quantum QSPR (QQSPR) equation are discussed. In principle, as any molecular structure can be associated to quantum mechanical density functions (DF), a molecular set can be reconstructed as a quantum multimolecular polyhedron (QMP), whose vertices are formed by each molecular DF. According to QQSPR theory, complicated kinds of molecular properties, like biological activity or toxicity, of molecular sets can be calculated via the quantum expectation value of an approximate Hermitian operator, which can be evaluated with the geometrical information contained in the attached QMP via quantum similarity matrices. Practical ways of solving the QQSPR problem from the point of view of QMP geometrical structure are provided. Such a development results into a powerful algorithm, which can be implemented within molecular design as an alternative to the current classical QSPR procedures. 展开更多
关键词 quantum similarity quantum multimolecular polyhedra (QMP) quantum QSPR (QQSPR) QQSPR fundamental equation QMP statistical-like collective functions QMP condensed collective indices classical QSPR-QSAR
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Restructuring of well-defined Pt-based electrode surfaces under mild electrochemical conditions
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作者 Jie Wei Wei Chen +2 位作者 Da Zhou Jun Cai Yan-Xia Chen 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第11期2792-2801,共10页
Since the 1980s,single-crystal Pt electrodes with well-defined surface structures have been deemed stable under mild electrochemical conditions(e.g.,in the potential region of electric double layers,underpotential dep... Since the 1980s,single-crystal Pt electrodes with well-defined surface structures have been deemed stable under mild electrochemical conditions(e.g.,in the potential region of electric double layers,underpotential deposition of hydrogen,or mild hydrogen evolution/OH adsorption)and have served as model electrodes for unraveling the structure-performance relation in electrocatalysis.With the advancement of in situ electrochemical microscopy/spectroscopy techniques,subtle surface restructuring under mild electrochemical conditions has been achieved in the last decade.Surface restructuring can considerably modify electrocatalytic properties by generating/destroying highly active sites,thereby interfering with the deduction of the structure-performance relation.In this review,we summarize recent progress in the restructuring of well-defined Pt(-based)electrode surfaces under mild electrochemical conditions.The importance of the meticulous structural characterization of Pt electrodes before,during,and after electrochemical measurements is demonstrated using CO adsorption/oxidation,hydrogen adsorption/evolution,and oxygen reduction as examples.The implications of present findings for correctly identifying the reaction mechanisms and kinetics of other electrocatalytic systems are also briefly discussed. 展开更多
关键词 Surface restructuring Well-defined Pt electrode surface Structure-performance relation In situ/operando electrochemical characterization ELECTROCATALYSIS
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Analysis on Capital Structure Theory and Enterprise Capital Structure Optimization
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作者 Xu Xiang 《International Journal of Technology Management》 2013年第5期117-119,共3页
Enterprise capital structure means the various resources, combination and relationships of enterprise raising capital as well as means the short or long debts, shareholders' rights and interest, and the proportional ... Enterprise capital structure means the various resources, combination and relationships of enterprise raising capital as well as means the short or long debts, shareholders' rights and interest, and the proportional relationships among constituting items. Capitals raised by enterprise from different ways constitute the capital sum. Because of changing enterprise operation, the capital structure is also various and it cannot be in a fixed proportion. Therefore, we need to optimize the capital structure of state-owned enterprises so as to reach the rational resources allocation and make the national economy develop soundly and rapidly. How to optimize it? This is a big problem that we have to face. Debt-to-equity swap at the moment is only the transition for correcting capital structure of state-owned enterprises. Decreasing stocks owned by state is the inevitable choice for optimizing enterprise stock right. 展开更多
关键词 Capital Structure Theory Enterprise Capital Structure Optimization.
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The structure and evolution of trade relations between countries along the Belt and Road 被引量:20
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作者 刘志高 王涛 +1 位作者 孙政远 陈伟 《Journal of Geographical Sciences》 SCIE CSCD 2018年第9期1233-1248,共16页
Trade facilitation is one of the five main agendas of the Belt and Road Initiative(BRI). Social network analysis has helped understand the complexity of trade networks, but existing studies tend to overlook the fact t... Trade facilitation is one of the five main agendas of the Belt and Road Initiative(BRI). Social network analysis has helped understand the complexity of trade networks, but existing studies tend to overlook the fact that not all bilateral trade relations are equally important to a country. To fill this gap in the literature, this paper focuses on the top 2 trade relations networks to illuminate the structure and evolution of B&R trade relations, the relative positions of different countries, and changes in the composition of trade communities(e.g., the community leaders) and the changing patterns of trade between them. We find rich dynamics over time both inter-and intra-communities. The overall international trade networks of B&R countries experienced a leadership change from Russia to China on one hand, some temporary communities experienced emergence, disappearance(e.g. the Kuwait-and Thailand-led communities) or reemergence(e.g. Poland-led community), and a community membership was generally consistent on the other hand. Since the future impacts of China's BRI will depend on the degree of integration of the connected regions, some countries with stable and high centrality indices(e.g. Russia, Singapore, Serbia, Greece, Turkey, Iran, Poland, Hungary and Romania) could be selected by China as strategic regional partners, and countries with a strategically important geographical position but weak trade links(e.g. Myanmar, Pakistan, and Belarus) should be prioritized. 展开更多
关键词 The Belt and Road Initiative international trade community core detection top trade partner
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Antagonistic effects of extracts from Artemisia rupetris L. and Leontopodium leontopodioides to CC chemokine receptor 2b(CCR2b)
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作者 YU Qin-Wei HU Jie +7 位作者 WANG Hao CHEN Xin ZHAO Fang GAO Peng YANG Qiu-Bin SUN Dan-Dan ZHANG Lu-Yong YAN Ming 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2016年第5期363-369,共7页
The present study was designed to establish a suitable assay to explore CCR2 b receptor antagonists from the natural products of Artemisia rupetris and Leontopodium leontopodioides. An aequorin assay was developed as ... The present study was designed to establish a suitable assay to explore CCR2 b receptor antagonists from the natural products of Artemisia rupetris and Leontopodium leontopodioides. An aequorin assay was developed as a cell-based assay suitable for 384-well microplate and used for screening CCR2 b receptor antagonists from natural products. Through establishing suitable conditions, the assay was shown to be suitable for screening of CCR2 b receptor antagonists. Seven compounds were identified in preliminary screening. Five of them showed evident dose-response relationship in secondary screening. The structure–activity relationship study suggested that 7-position hydroxyl group of flavonoids was necessary, a polar group should be introduced on the 3-position, and the substituents on 2-position benzene ring of flavonoids have little influence on the potentency of the inhibition activity on CCR2 b receptor. The ortho-position dihydroxyl structure in quinic acid compounds may be important. In conclusion, Compounds HR-1, 5, 7, and AR-20, 35 showed activity as antagonist of CCR2 b receptor, which shed lights on the development of novel drugs as CCR2 b receptor antagonists for preventing inflammation related diseases. 展开更多
关键词 CCR2b antagonist Inflammation Aequorin assay Artemisia rupetris Leontopodium leontopodioides
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