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城市社会学教材建设中的问题和思考

杭州师范大学学报（社会科学版） 2010年第2期32卷 103-108页

作者：蔡禾中山大学城市社会研究中心广东广州510275

城市社会学对象的模糊性和边界的广泛性对编写教材带来的问题是不可否认的,但从城市社会学理论的发展历史来看,其核心问题始终围绕着人类群体生活与都市环境的关系。目前,国内教材更注重"体系"的完整性,国外教材更具有"问题"意识;国内... 详细信息

城市社会学对象的模糊性和边界的广泛性对编写教材带来的问题是不可否认的,但从城市社会学理论的发展历史来看,其核心问题始终围绕着人类群体生活与都市环境的关系。目前,国内教材更注重"体系"的完整性,国外教材更具有"问题"意识;国内教材的内容更为宏观,国外教材相对更为具体。作者认为,在编写《城市社会学》教材时,应该有两个方面的考虑。一是这门课程的内容不是如何完整地介绍和分析城市体系,而是围绕历史上形成的核心问题来展开其篇章内容,考虑应该把哪些领域和问题纳入其中;二是对纳入其中的领域和问题,不是停留在对这些领域和问题的概念解释和现象描述,还要对前人在这些领域和问题研究上形成的理论和观点加以整理、介绍和讨论。在此基础上,提出了自己的教材编写意见。

关键词：城市社会学研究对象核心问题

Si(111)Electrode/Electrolyte Interfacial Studied by in-situ Second Harmonic Generation

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Chinese Journal of Chemical Physics 2020年第5期33卷 554-560,I0078页

作者： cai-he Liu Rui-peng Bai Yu Bai Yuan Guo Zhen Zhang Beijing National Laboratory of Molecular Sciences State Key Laboratory of Molecular Reaction DynamicsCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of the Chinese Academy of Sciences Beijing 100049China

Si(111)electrode has been widely used in electrochemical and photoelectrochemical *** potential dependent measurements of the second harmonic generation(SHG)were performed to study Si(111)electrode *** different azimuthal angles of the Si(111)and under different polarization combinations,the curve of the intensity of SHG with extern potential has a different form of line or *** analysis showed that these differences in the potential-dependence can be explained by the isotropic and anisotropic contribution of the Si(111)*** change in the isotropic and anisotropic contribution of the Si(111)electrode may be attributed to the increase in the doping concentration of Si(111)electrodes.

关键词： Second harmonic generation Si(111)electrode/electrolyte Doping density

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关于物流企业税收政策的几个问题

中国流通经济 2006年第8期20卷 19-20页

作者：贺登才中国物流与采购联合会北京市100045

为了解决物流企业税收政策方面存在的突出问题,国家有关部门相继采取了一系列政策措施。本文认为,从国家政策层面解决物流企业在税收方面遇到的突出问题,是国家有关部门支持我国现代物流业发展的重要举措。但是,物流业是新兴的产业,涉... 详细信息

为了解决物流企业税收政策方面存在的突出问题,国家有关部门相继采取了一系列政策措施。本文认为,从国家政策层面解决物流企业在税收方面遇到的突出问题,是国家有关部门支持我国现代物流业发展的重要举措。但是,物流业是新兴的产业,涉及面广,各地情况千差万别,对国家政策的理解和执行也不尽一致,在政策执行过程中存在着这样或那样的问题,需要在实践中研究解决。作者在调研基础上提出了十个问题:一是关于物流企业的认定问题;二是关于试点企业所属企业的问题;三是关于自开票纳税人资格认定的问题;四是关于非试点物流企业的问题;五是关于第二批试点企业的申报问题;六是关于整合个体户车辆的发票抵扣问题;七是关于仓储业发票税率偏高和不能抵扣增值税的问题;八是关于仓库租金能否抵扣的问题;九是关于所得税属地缴纳的问题;十是关于减轻税负和涵养税源的关系问题。

关键词：物流企业物流产业产业发展税收政策

工作场所空气中异佛尔酮热解吸气相色谱测定法

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中华劳动卫生职业病杂志 2009年第5期27卷 292-294页

作者：陈卫何彩深圳市疾病预防控制中心理化检验科 518020

目的建立工作场所空气中异佛尔酮的热解吸气相色谱测定方法。方法活性炭吸附采样，选用FFAP毛细管色谱柱分离，热解吸气相色谱法测定。结果该方法在0～3．6μg/ml范围呈线性关系；样品在炭管中可保存10d；方法的重现性好，不同浓度... 详细信息

目的建立工作场所空气中异佛尔酮的热解吸气相色谱测定方法。方法活性炭吸附采样，选用FFAP毛细管色谱柱分离，热解吸气相色谱法测定。结果该方法在0～3．6μg/ml范围呈线性关系；样品在炭管中可保存10d；方法的重现性好，不同浓度的相对标准偏差为0．65％～3．16％；方法的最低检出限为0．015μg／ml，解吸效率为89．66％～92．72％，采样效率为99．34％～100．00％，100mg活性炭对异佛尔酮的穿透容量为13．6mg。空气中可能与异佛尔酮共存的丙酮、二异丁基甲酮、环己酮等在该方法条件下不干扰测定。结论该方法各项指标均达到《工作场所空气中有毒物质检测方法研究规范》的要求，适用于工作场所空气中异佛尔酮的现场监测。

关键词：空气异佛尔酮气相色谱

Proliferation and adipogenic differentiation of human adipose-derived stem cells isolated from middle-aged patients with prominent orbital fat in the lower eyelids

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Plastic and Aesthetic Research 2016年第1期3卷 322-327页

作者： Guang-Peng Liu cai-he Liao Yi-Pin Xu Department of Plastic and Reconstructive Surgery Shanghai Tenth People's HospitalTongji University School of MedicineShanghai 200072China

Aim:To evaluate the age-related effects on the adipogenic differentiation and proliferation potentials of human orbital adipose-derived stem cells(OASCs).Methods:Orbital adipose samples were harvested from the central fat compartment in the lower eyelids of 10 young and middle-aged patients during routine blepharoplasty *** assessment of the morphological changes of adipocytes with aging,OASCs were isolated from the fat samples and expanded in *** in the stem cell colony number(fibroblast colony-forming unit),growth rate and phenotype characterization(flow cytometry analysis)were *** ability of OASCs to differentiate into adipocytes was determined by oil red O staining and the mRNA expression level of peroxisome proliferator-activated receptorγ.Results:Fat cell size showed a decreasing trend with advancing *** no difference was found in the expression of cell surface markers,the colony number and proliferative rate of OASCs from middle-aged donors were significantly lower than those from the young *** adipogenic differentiation capacity of middle-aged OASCs was also *** differences were statistically significant(Phe data showed that the progenitor cell number,proliferation capacity and adipogenic potential of OASCs decreased with aging,suggesting that using OASCs from elderly patients for therapeutic purposes might be restricted.

关键词： Orbital fat adipose-derived stem cells progenitor cell number proliferation rate adipogenic differentiation

Highly birefringent octagonal photonic crystal fibers

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Highly birefringent octagonal photonic crystal fibers

Sheepdog Driven Algorithm for Sheep herd Transport

“广东省光学学会2013年学术交流大会”暨“粤港台光学界产学研合作交流大会”

作者： Zhang Shao-hua Sun Jin-hai cai he Beijing Institute of Environment Features

A novel highly birefringent photonic crystal fiber(PCF) based on an octagonal structures with isosceles triangular-latticed cladding is *** a full-vector finite element method (FEM) simulator(COMSOL Multiphysics),we study the modal birefringence of the fundamental modes with different parameters in such *** addition,the proposed octagonal PCF is compared with hexagonal PCF with the same air-filling fraction(f =0.41811),and found that the property such as birefringence and confinement loss of octagonal PCF is relatively better than that of hexagonal PCF.

关键词： photonic crystal fiber finite element method birefringence octagonal structures

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Sheepdog Driven Algorithm for Sheep Herd Transport

A Self-Organized Line Marching Formation Control Algorithm

第40届中国控制会议

作者： Yu Liu Xin Li Meiqi Lan Yaqi he he cai Huanli Gao School of Automation Science and Engineering South China University of Technology

So far, most of the existing works on swarm systems are concerned with the collective motions. In this work, a somehow reverse problem is investigated, i.e., how an agent can interact with/control a swarm system. In particular, we consider the sheep herd transport problem: a herd of sheep is driven by a single sheepdog from the start place to the sheepfold. The rules governing the behaviors of the sheep are preset and known to the sheepdog, and the objective is to design the rule for the sheepdog to fulfil the transport task. Inspired by the behaviors of true sheepdogs, we have developed a backward semi-circle reciprocation algorithm featuring dynamic turn-around point selection. Numerical results are provided to evaluate the proposed algorithm.

关键词： artificial intelligence bio-inspired algorithm sheep herd transport swarm system

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A Self-Organized Line Marching Formation Control Algorithm

第40届中国控制会议

作者： Yu Liu Yuheng he Yingnan Zhen Shuping Guo Huanli Gao he cai School of Automation Science and Engineering South China University of Technology

Most of the existing exact formation control algorithms for multiagent systems are label-specified, i.e., the desired position for each agent in the formation is pre-specified by its label. In this paper, a self-organized control algorithm is proposed for line marching formation of a team of planar kinematic robots. The desired positions for the robots in the formation are not label-specified, but determined dynamically. By constantly forming a chain of leader-follower pairs, exact formation can be achieved by pairwise leader-follower tracking. Comprehensive simulation results are provided to evaluate the performance of the proposed control algorithm.

关键词： kinematic robot line marching formation multiagent system self-organized control algorithm

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腐蚀性环境中基桩选型研究

建筑结构 2019年第A1期49卷 798-799页

作者：贺彩京鼎工程建设有限公司

因土壤腐蚀环境的复杂性,基桩腐蚀度无法量化计算,按目前规范推荐的腐蚀性分级方式,结合腐蚀性机理,设计人员应提出科学合理的KS抗硫酸盐腐蚀等级或DRCM氯离子迁移系数等级,并借助于当地成熟的外加剂或矿物掺合料提高桩身防腐能力,同时... 详细信息

因土壤腐蚀环境的复杂性,基桩腐蚀度无法量化计算,按目前规范推荐的腐蚀性分级方式,结合腐蚀性机理,设计人员应提出科学合理的KS抗硫酸盐腐蚀等级或DRCM氯离子迁移系数等级,并借助于当地成熟的外加剂或矿物掺合料提高桩身防腐能力,同时加强桩头、桩尖和接桩部位的防腐措施,达到延长基桩耐久性目标。

关键词：腐蚀硫酸根离子氯离子基桩选型桩身防腐