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Indulgences of Intellectuals: The Formation and Connotation of Taiwanese Leftists' Ideas of the “People's Communication”
No full text张铭清，厦门大学新闻传播学院教授、博士生导师，两岸关系和平发展协同创新中心社会整合平台主任；温晔，厦门大学新闻传播学院博士研究生。【中文摘要】过往有关台湾新闻传播思想史的研究,多以“三民主义新闻思想”和西方自由主义新闻思想为主线。在上述两条线索之外，台湾左翼的新闻传播思想则一直鲜为人知，其中以陈映真等人提出的“民众传播”最具代表性。俄国民粹主义思想与台湾乡土文学运动在陈映真建构“民众传播”理念的过程中起到了重要作用。“民众传播”的实施主体旨在对“保守”的知识分子进行启蒙和改造，促成他们与普通民众联合，实现左翼群体社会变革的宏大目标。
【Abstract】Previous studies on the intellectual history of journalism and communication in Taiwan were primarily focused on the “journalistic thought of the Three Principles of the People” and the Western liberalist thoughts of journalism. Taiwanese leftists’ ideas of journalism and communication have received relatively scant scholarly attention. The most typical idea among them is “people's communication”，proposed by Chen Yingzhen and his fellow intellectuals. Russian populism and the Third Leftist Movement in Taiwan exerted a significant impact on Chen Yingzhen's formulation of the a people's communication”.“People's communication” was a platform that could be used by “progressive intellectuals” to enlighten and remold “conservative intellectuals” and to unite intellectuals and the public， thereby realizing the leftists’ lofty ideals of social revolution
【原生态生鲜连锁超市】经营模式初探
Full text link本条目为“厦门大学百年校庆”的演示文稿。连庆达是厦门大学1985届计算机科学系校友。内容摘要：元初食品 Sungiven Foods 简介；商业逻辑(doing the right things)；经营策略(doing things right)；创业体
Application of Atomically Precise Metal Nanoclusters in Electrocatalysis
Full text link金属纳米团簇（M NCs）是由几个到数百个金属原子组成,其尺寸一般小于2 nm。金属纳米团簇在许多催化反应中表现出高的催化活性和选择性,这与金属纳米团簇具有高的比表面积、较多暴露的活性原子,以及与金属纳米粒子（M NPs）不同的电子结构有关。金属纳米团簇确定的组成和结构使其成为一种新型模型催化剂,对纳米团簇的催化性能研究有利于人们深入理解催化剂结构-性质之间的关系,更利于催化剂的理性设计与发展。结合近几年国内外和本课题组在金属纳米团簇电催化领域的研究进展和现状,本文对该领域的代表性工作进行了简要综述,并对其未来在电催化领域的应用前景和需要解决的关键问题进行了展望。Metal nanoclusters (M NCs) consist of only several to a few hundred of metal atoms and possess core sizes less than 2 nm. Owing to the quantum size effect, the electronic states of M NCs evolve to discrete levels similar to the molecule energy gaps, other than a continuous density of states to produce plasmon characteristic of bulk metal nanoparticles (M NPs). In comparison with the conventional M NPs, M NCs exhibit dramatically unique electronic and optical properties, such as molecule-like energy gaps, strong photoluminescence and high catalytic properties, which make them promising for potential application in numerous fields, such as catalysis, chemical sensors, electronics, biological labeling and biomedicine. As a new type of highly efficient catalysts, MNCs have shown high catalytic activity and unique selectivity in many catalytic reactions, which are related to their ultrasmall size with relatively high surface area-to-volume ratio, high density of exposed active atoms, and the unique electronic structure different from that of bulk M NPs. For example, the M NCs showed good performances in many catalytic reactions, such as CO oxidation, propylene epoxidation, electrocatalytic water oxidation, propane dehydrogenation, acetylene cyclotrimerization and hydrogenation and polymerization reactions. M NCs can be used as model catalysts for theoretical simulation of the reaction pathway due to the precise compositions, atomically precise and tunable structures, which is helpful to study the intrinsic relationship between structure and property of nanostructure, and to rational design and fabricate advanced catalysts. In this review article, based on the present status of this field, we highlight the development of metal nanoclusters in recent years with focusing mainly on their application in electrocatalysis, including for fuel cell anode and cathode reactions, water splitting reaction and CO2 reduction. Finally, we give a brief outlook on the application of metal nanoclusters in electrocatalysis and the possible challenges.国家自然科学基金项目(21633008);国家自然科学基金项目(21773224);科技部重点研发计划(2020YFB1506001)通讯作者:陈卫E-mail:[email protected]:WeiChenE-mail:[email protected].中国科学院长春应用化学研究所 电分析化学国家重点实验室,吉林 长春 1300222.中国科学技术大学应用化学与工程学院,安徽 合肥 2300261. State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry,Chinese Academy of Sciences, Changchun 130022, Jilin, China2. University of Science and Technology of China, Hefei 230026, Anhui, Chin
Atomically thin photoanode of InSe/graphene heterostructure
Full text link很多物理和化学过程都发生在固体电极与溶液的表界面处，因而表面处离子的吸附、聚集及其在表面的反应都对整个反应过程起到至关重要的作用。然而使用传统的固体电极通常表现出的是体相和表面的复合性质，使得单纯研究电极材料表面效应及表面离子的动力学还存在挑战。二维材料由于其具有单原子层的厚度，晶体中所有原子都处在表面，因而可以作为一种理想的模型体系来仅针对此类表面现象进行研究。课题组选择光电化学池（PEC）分解水反应中的决速步骤氧析出半反应（OER）以作为研究表面离子行为的探针反应。光电极选择同时具有高迁移率、匹配的能级结构以及被抑制的光生电子-空穴复合的单层的二维硒化铟（InSe）材料。并且在手套箱提供的惰性气氛中用单层石墨烯对InSe进行封装，保证了光电极测试条件下长时间的稳定性。该工作揭示了二维异质结表面性质与反应活性的内在联系，希望能为研究电极表面离子效应提供新的材料平台。后续通过选择具有合适表面性能的二维材料，并与传统光电极材料结合，有望发展新型的高性能光阳极材料。
这一研究工作的实验部分是在化学化工学院曹阳教授指导下完成，博士生郑海红、鲁艺珍与广东工业大学轻工化工学院叶凯航博士为论文的共同第一作者。理论计算部分在程俊教授的指导下，由博士生胡晋媛完成。Achieving high-efficiency photoelectrochemical water splitting requires a better understanding of ion kinetics, e.g., diffusion, adsorption and reactions, near the photoelectrode's
surface. However, with macroscopic three-dimensional electrodes, it is often difficult to
disentangle the contributions of surface effects to the total photocurrent from that of various
factors in the bulk. Here, we report a photoanode made from a InSe crystal monolayer that is
encapsulated with monolayer graphene to ensure high stability. We choose InSe among other
photoresponsive two-dimensional (2D) materials because of its unique properties of high
mobility and strongly suppressing electron–hole pair recombination. Using the atomically thin
electrodes, we obtained a photocurrent with a density >10 mA cm−2 at 1.23 V versus
reversible hydrogen electrode, which is several orders of magnitude greater than other 2D
photoelectrodes. In addition to the outstanding characteristics of InSe, we attribute the
enhanced photocurrent to the strong coupling between the hydroxide ions and photogenerated holes near the anode surface. As a result, a persistent current even after illumination ceased was also observed due to the presence of ions trapped holes with suppressed
electron-hole recombination. Our results provide atomically thin materials as a platform for
investigating ion kinetics at the electrode surface and shed light on developing nextgeneration photoelectrodes with high efficiency.The experimental work was supported by the National Key R&D Program of China
(2018YFA0306900 and 2018YFA0209500), the National Natural Science Foundation of
China (21872114), and China Postdoctoral Science Foundation (2020M682616).
该工作得到了国家重点研究计划（2018YFA0306900、2018YFA0209500），国家自然科学基金（21872114）、中国博士后科学基金（2020M682616）的支持
Study on Li3BO3 Interface Modification of Garnet Solid Electrolyte
Full text link石榴石固体电解质由于其高的离子电导率,对锂金属稳定等优点成为了下一代高性能锂电池的重要研究方向之一。但锂金属负极界面浸润性与锂枝晶问题限制了其应用。本文通过简单的液相沉积结合高温烧结的方法,在石榴石固体电解质片表面构建了一层稳定的硼酸三锂(Li3BO3)修饰层。研究表明,Li3BO3修饰层可以有效改善石榴石固体电解质与锂金属负极界面接触,促进锂的均匀沉积/溶出,从而抑制锂枝晶生长,提高界面稳定性。Li3BO3修饰后石榴石电解质片与锂金属之间紧密结合,Li/石榴石界面阻抗由修饰前的1780 Ω·cm2降低至58 Ω·cm2。得益于界面接触的改善,Li3BO3修饰后的LLZTO电解质组装的对称电池可以在0.1 m·cm-2的电流密度下稳定工作超过700 h。而未修饰的对称电池在0.05 mA·cm-2的电流密度下短时间工作即出现微短路现象。Garnet solid-state electrolytes have become the research hotspot due to their high ionic conductivity, wide electrochemical stability window and good air stability. However, there are still a series of problems to be solved. The poor contact between the lithium (Li) metal and garnet pellet make it difficult to build stable ion diffusion channels, resulting in large interfacial resistance. The continuous growth of lithium dendrites can penetrate the electrolyte pellet and cause a short circuit in the solid-state battery. Herein, a novel strategy is proposed to improve the wettability of LLZTO electrolyte with Li metal, via interfacial modification of LLZTO electrolyte with tri-lithium borate (Li3BO3). Li3BO3 is chemically stable with Li metal and effective to improve the wettability between Li and LLZTO pellet. A stable and even Li3BO3 interfacial layer was constructed on the LLZTO electrolyte surface by liquid-phase deposition combing with high temperature sintering. The low melting point (700℃) of Li3BO3 facilitated the formation of a dense and uniform coating layer. SEM images show that the Li3BO3 layer was about 2.5 μm thick and completely covered the pellet surface. Intimate contact between Li metal and LLZTO electrolyte could be realized after the Li3BO3 interfacial modification, which was confirmed by SEM analysis and wettability experiment. Benefiting from the significantly improved interfacial contact, the interfacial impedance was dramatically reduced from 1780 Ω·cm2 of Li/LLZTO interface to 58 Ω·cm2 of Li/LBO-LLZTO interface. The Li|LBO-LLZTO|Li symmetric cell could produce a low overpotential and work stably at the current density of 0.1 mA·cm-2 for more than 700 h. By contrast, the Li|LLZTO|Li symmetric cell displayed high overpotential and was short circuited after 20 min of lithium plating/stripping at the current density of 0.05 mA·cm-2. Our results show that Li3BO3 interfacial modification is an effective approach to improve the wettability and interfacial stability between Li metal and garnet electrolyte, which is a key to the successful use of solid-state battery.国家重点研发计划项目(2018YFB0905400);国家自然科学基金项目(21875196);国家自然科学基金项目(21935009);国家自然科学基金项目(U1732121);福建省引导性计划项目(2019H0003);厦门大学大学生创新创业训练计划项目(S201910384404)通讯作者:龚正良E-mail:[email protected]:Zheng-LiangGongE-mail:[email protected]厦门大学能源学院,福建 厦门 361005College of Energy, Xiamen University, Xiamen 361005, Fujian, Chin
Theoretical Study on Electrical Properties of Molecular Junctions of Viologen Derivatives
Full text link本文基于密度泛函(DFT)结合非平衡格林函数(NEGF)的方法,以具有氧化还原中心的紫罗碱衍生物(N,N′-bis(4-thioalkyl)-4,4′-bipyridinium, HS-4V4-SH)功能分子构造Au(111)/S-4V4-S/Au(111)分子结,详细分析了分子在三种价态V、V+和V2+下的电学性质与分子的几何结构和电子结构的关系。基于对三种价态透射系数分析结果表明,在零偏压下,V与V+的电导值比V2+高了两个数量级,4V4分子结的电导随两个吡啶环之间夹角的增大呈线性减小。同时,理论计算结果也表明,增加烷基链(HS-nVn-SH, n = 2 ~ 7)的数目,发现分子结电导值呈指数形式衰减,其每个亚甲基的衰减因子约为1,与烷基二硫醇分子的接近。In this paper, the electrical properties of molecular junctions formed N,N′-bis(4-thioalkyl)-4,4′-bipyridinium (viologen) moiety between two gold (Au) electrodes have been investigated by combining density functional theory and non-equilibrium Green’s functional approach. To modulate the viologen molecule to be a cation with one and two positive charges (V+ and V2+), we introduce one and two trifluoroacetic acid ions (TFA-) around the molecule, respectively. The valence states of V+ and V2+ are confirmed by checking Mulliken and NBO charges. Then the relationship between molecular conductance and electronic structures of the neutral state V, the radical state V+ and dication V2+ are analyzed in detail. The results in analyzing transmission spectra of the three states reveal that the conductance values of V and V+ are two orders of magnitude larger than that of V2+. This suggests that the redox states of viologen molecules can be used to realize the function of molecular switches. Our calculated results also show that increasing the torsion angle between two pyridine rings of the S-4V4-S molecule will decrease the conductance. By comparing different ions of TFA、PF6 and BF4, the calculated results show that the molecular junction conductance decreases about 3 times when the torsion angle increases by about 6°. It indicates that increasing the torsion angle of the dication V2+ can improve significantly switching ratio of viologen derivatives molecules. At the same time, the calculated results show that increasing the number of methylene groups in alky chains (HS-nVn-SH, n = 2 ~ 7), the conductance values of molecular junctions decrease exponentially, and the attenuation factor of each methylene is about 1 close to alkanedithiol molecules in literatures experimentally and theoretically. This also shows that as the alkyl chain length increases, the DFT-NEGF theoretical method can better predict the zero-bias conductance of the viologen derivative molecule.国家自然科学基金项目(21533006);国家自然科学基金项目(21621091);国家自然科学基金项目(21773197);福建省创新人才通讯作者:吴德印E-mail:[email protected]:De-YinWuE-mail:[email protected]厦门大学化学化工学院化学系,固体表面物理化学国家重点实验室,福建 厦门 361005Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, Chin
Research Progress on Transition State of Organic Electrode Materials
Full text link有机电极材料具有理论比容量大、结构可设计性强、加工使用过程环境友好等优点被广泛应用于二次电池的研究中。有机电极材料在氧化还原过程会产生具有不成对电子的自由基中间体,自由基中间体的稳定程度影响电极材料的电化学性能。通过改变材料的结构可以调控自由基中间体的稳定性,从而优化有机电极材料的电化学性能。本文对有机电极材料在电化学过程中产生的自由基中间体进行了分类介绍,阐明了材料结构、自由基中间体稳定性和电化学性能之间的关系。With the increasing requirements for high energy density, long lifetime, high safety, environmentally friendly fabrication, and sustainable development of large energy storage devices, the society calls for new electrode materials in rechargeable batteries beyond traditional inorganic materials which are limited by specific capacity. Organic electrode materials have been widely used in rechargeable batteries due to their advantages of large theoretical capacity, designable structures and environmentally friendly fabrications. In this review, the radical intermediates of organic electrode materials produced in the charging-discharging process (redox reaction) and their types are systematically reviewed. The stability of radical intermediates controlled by changing the structure of materials, and thereby, the optimization in the electrochemical performance of organic electrode materials are described. The reasons for the optimization of electrochemical performance are analyzed in depth, and the mechanism is discussed. This review provides guidance for improving the electrochemical performance of secondary batteries with organic materials as electrodes in the future.国家自然科学基金(21875206);国家自然科学基金(21403187);国家自然科学基金(21875097);河北省自然科学基金(B2019203487);深圳市科技创新委员会基础研究(JCYJ20170412153139454)通讯作者:卢周广,黄苇苇E-mail:[email protected];[email protected]:Zhou-GuangLu,Wei-WeiHuangE-mail:[email protected];[email protected].燕山大学亚稳材料制备技术与科学国家重点实验室,河北 秦皇岛 0660042.南方科技大学材料科学与工程系,广东 深圳 5180553.燕山大学环境与化学工程学院,河北 秦皇岛 0660041. State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, Hebei, China2. Department of Materials Science & Engineering, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China3. School of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, Hebei, Chin
Continget Factors,Expected Usefulness and Implementation of Management Accounting:A Questionnaire Survey Based on Administrative and Public Service Institutions
No full text李建发，厦门大学管理学院教授、博士生导师；范樟妹，厦门大学管理学院博士研究生；张国清，厦门大学管理学院教授、博士生导师。【中文摘要】近年来，管理会计应用成为行政事业单位的内在管理要求，也是推进国家治理体系和治理能力现代化建设的一项基础性工具，它通过提供多层次信息支持单位决策，提高公共资金使用效益和管理绩效。但是，我国行政事业单位管理会计实践及其影响因素的经验证据还比较欠缺。基于行政事业单位的问卷调査，探讨权变因素、有用性预期对管理会计应用的影响，结果表明,我国行政事业单位应用多个管理会计工具方法,但应用成效普遍不高,且文化、组织、资源、信息四个权变因素和有用性预期显著影响行政事业单位管理会计的应用。
【Abstract】In recent years，the adoption of management accounting has become an inherent requirement of internal management within administrative and public service institutions ； it has also emerged as a fundamental tool to facilitate the modernization of the national governance system and capacity，providing multi - level information for internal operation decisions and enhancing financial efficiency and management performance. However，the foundation for management accounting practices is weak in Chinas administrative and public service institutions，and there is a lack of evidence of management accounting practice and its influencing factors. Based on a questionnaire，this paper examines the relationship between the contingent factors，perceived usefulness and the adoption and success of management accounting. The results show that various management accounting tools and methods are in use，but with low levels of success. The regression results show that the implementation of management accounting has a significant positive correlation with four contingent factors (namely， culture，organization，resources and information) and expected usefulness.国家社会科学基金重大项目“绩效管理导向下的中国政府成本体系研究”（20&ZD115);教育部人文社科重点研究基地重大项目“政府会计和报告模式变革与公共资源管控研究”（18JJD790009)；国家社会科学基金重点项目“公共产权视角下的政府资产治理与财务会计问题研究”（20AGL013)；国家“万人计划”哲学社会科学领军人才项目
The Key Issues and Promotion Path of the Modernization of Higher Education Governance Systems and Governance Capacity
No full text蒋凯，北京大学教育学院教授、博士生导师；王涛利，北京大学教育 学院博士研究生。【中文摘要】随着高等教育管理方式的转变，决策权力如何在政府、高校、市场和其他利益相关主体之间合理分配,成为我国高等教育治理体系与治理能力现代化的关键问题。鉴于高等教育的多重属性,从理念、制度和能力三个维度对政府、高校、企业和社会组织等多元主体之间的关系进行调整，构建多元主体共同治理的高等教育权力格局，才能切实应对高等教育现代化建设的实践困境。推进我国高等教育治理体系与治理能力现代化，需要树立依法治理的治理理念，逐步完善政府与高等教育的关系;构建有序运行的现代大学治理体系，提升高校自主管理能力;发挥多元主体智慧，提升多元共治的高等教育治理能力。
【Abstract】With the change of higher- education administration patterns，how to reasonably distribute decision- making power among government，academics，the market and other stakeholders has become a key issue in the modernization of China's higher- education governance system and governance capacity. In view of the multiple attributes of higher education，it is necessary to adjust the relationship among the government，universities，enterprises and social organizations in terms of the three dimensions of concept，system and ability，while it is also important to construct a higher- education power pattern of joint governance by multiple entities，thereby effectively addressing the realistic dilemmas in the modernization of higher education. To promote the modernization of China's higher- education governance system and governance capacity ，the following steps are required ： establishing a concept of governance by law and gradually improving the relationship between the government and higher education ； enhancing the autonomous management ability of colleges and universities and building an orderly modern university governance system ；giving full play to the wisdom of multiple entities and enhancing higher-education governance capacity under the joint governance of multiple entities.中国高等教育学会2020年度重点委托课题“新时代高等教育治理体系与治理能力现代化研究” (2020ZDWTO1
Has the Agglomeration of Producer Services Improved the Economic Efficiency of Chinese Cities: A Study from the Perspective of Industrial Heterogeneity and Difference in City Size
No full text袁冬梅，湖南师范大学商学院教授、博士生导师，经济学博士；李恒辉，湖南师范大学商学院博士研究生。【中文摘要】加快发展生产性服务业是促进中国产业转型升级,进而提高城市经济效率和实现高质量增长的重要途径。利用2004—2018年城市面板数据对生产性服务业集聚与中国城市经济效率之间的关系进行检验。实证发现:(1)生产性服务业集聚对城市经济效率的影响整体呈倒U型，目前正处于促进城市经济效率的上升阶段；(2)分产业层次看，对城市经济效率的倒U型影响主要来源于高端生产性服务业集聚，低端生产性服务业集聚与城市经济效率呈线性关系；（3)分城市规模看，不同规模城市生产性服务业集聚均促进了城市经济效率提升，其中Ⅰ型和Ⅱ型大城市的促进作用最大,中等城市作用最小。
【Abstract】Speeding up the development of producer services is an important way to promote Chinas industrial transformation and upgrading in order to improve urban economic efficiency and achieve high-quality growth. Based on urban panel data from 2004 to 2018，this paper examines the relationship between the agglomeration of producer services and urban economic efficiency in China. The empirical results show that: (1) the impact of the agglomeration of producer services on urban economic efficiency is inverted U-shaped，which is currently in the upward phase of promoting urban economic efficiency; (2) at the industrial level，the inverted U-shaped impact on urban economic efficiency essentially stems from the agglomeration of high-end producer services，and there is a linear relationship between the agglomeration of low-end producer services and urban economic efficiency; and (3) in terms of city size，the agglomeration of producer services in cities of different sizes enhances urban economic efficiency，in which type I and II cities play the most important role，while medium-sized cities play the least role. The foregoing conclusions provide empirical support for cities of different sizes to focus on the development of producer services in order to improve economic efficiency.教育部重大招标课题攻关项目“发达国家‘再工业化’对中国制造转型升级的影响及对策研究”(17JZD022)；国家社会科学基金一般项目“产业结构转型升级与稳就业协同推进的实现机制和支撑政策研究”(20BJL141)；湖南省研究生科研创新重点项目“疫情冲击下出口贸易转型升级影响制造业就业的机理和政策研究”(CX20200475