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Research Progress of Sulfur Cathode Catalytic Conversions for Lithium-Sulfur Batteries
No full text单质硫作为电池的正极材料,其电化学过程历经多个步骤,完全放电生成最终产物是一个2电子反应. 低阶多硫化锂的生成需克服一定的能垒,且由Li2S2得到一个电子还原生成Li2S的反应是速控步骤. 硫正极的反应动力学是决定锂硫电池电化学性能,如比能量、比功率、低温性能等的关键因素. 提高速控步骤的反应动力学还能加速可溶性多硫化锂Li2S4向不溶性Li2S2和Li2S的转化,有利于减缓或消除多硫化锂的“穿梭效应”. 近年,已有大量的过渡金属氧化物、硫化物、碳化物、氮化物、磷化物,单原子催化剂和氧化还原电子中继体等被应用于催化硫正极反应,提高了电极的电化学性能和循环稳定性. 但是,目前详细的催化反应机制尚不完全清晰. 本文重点综述了这些化合物在硫正极反应中的作用机制,总结了近年来的研究进展,并对硫正极催化转换反应的研究和发展进行了展望.The electrochemical reduction of sulfur (S) takes place through multistep reactions when S is used as a cathode material. The complete discharge of S to form final product lithium sulfide (Li2S) is a two-electron reaction. The formation of low-order lithium polysulfides (LiPS) needs to overcome certain energy barriers. And the reduction of Li2S2 to Li2S is the rate-limited step. The reaction kinetic of sulfur cathode is the critical key to determine the electrochemical performance of Li-S batteries, such as specific energy, specific power and low temperature performance, etc. Accelerating the rate-limited step kinetics of sulfur cathodes can promote the conversion of soluble Li2S4 to insoluble Li2S2/Li2S, contributing to suppressed or eliminated “shuttle effect”. Recently, there are lots of transition metal oxides, sulfides, carbides, nitrides, phosphate, single atoms and redox electron mediators being applied in the preparations of sulfur cathodes, which improve the electrochemical performances and cycle stabilities. However, detailed mechanism of catalytic reaction is not completely clear. This review focuses on the functional and catalytic mechanisms of those metal compounds towards polysulfides, summarizes the recent research progress, and prospects the development and ongoing research of sulfur cathodes.中国科学院战略性先导科技专项(XDA17020404);国家重点项目研发计划(2016YFB0100100)通讯作者:陈剑E-mail:[email protected]:CHENJianE-mail:[email protected].中国科学院大连化学物理研究所,辽宁 大连 1160232.中国科学院大学,北京 1000491. Dalian Institute of Chemical Physics, Chinese Academy of Science, Dalian 116023, Liaoning, China2. University of Chinese Academy of Sciences, Beijing 100049, Chin
The Construction and Significance of the Discourse System of Chinese Textbooks for Primary and Secondary Schools
No full text苏新春，厦门大学人文学院、厦门大学嘉庚学院、国家语言资源监测与研究教育教材中心、福建省人文社科研究基地“两岸语言应用与叙事文化研究中心”教授、博士生导师，语言学博士；龙东华，厦门大学人文学院博士研究生。【中文摘要】话语体系研究近些年以很快的速度进入了中国学术界的中心舞台，国家社科基金自2008年以来13次的年度课题指南清楚显示了话语体系研究在众多人文学科中的推广速度。语文教材是一种典型的话语体系，且是代表国家以教育者身份出现的话语体系，有着权威性、系统性、全面性、强制性等特点。语文教材话语体系的话语单位清晰、结构层级分明、功能分工明确,话语形式与话语内容紧密结合,功能多样综合。语文教材话语体系包括课程大纲、教材、课文、教材语言四个层级，每一层级都有着丰富的话语内容,特别是在课文这一典型语篇身上，充分展示了语文教材的话语形式、话语内容、话语功能的多样性。中小学语文教材话语体系的建构对提高教材研究的科学性、理论性有重要意义。
【Abstract】 In recent years，discourse system research has rapidly taken center stage in Chinese academic circles. The 13 annual project guides released by the National Social Science Foundation since 2008 clearly demonstrate the rapid promotion of discourse system research in many humanities disciplines. Chinese textbooks are a typical discourse system. Appearing as an educator on behalf of the state，this system is authoritative，systematic，comprehensive and mandatory in nature. The discourse system of Chinese textbooks has clear discourse units， a clear structure and a clear division of functions .The form of discourse is closely connected to the content of discourse，and its functions are diversified. The discourse system of Chinese textbooks consists of four levels: syllabus，textbook，text and textbook language. Each level has rich discourse contents. Especially in the texts，which are typical passages，each level fully demonstrates the diversity of discourse forms，contents and functions of Chinese textbooks. The construction of the discourse system of Chinese textbooks in primary and secondary schools is of great significance to improve the scientific and theoretic nature of textbook research.国家语委“十三五”科研规划2019年度课题“中小学语文教材话语体系问题研究”（WT135-54);国家语委“十三五”科研规划2019年度课题“汉字文化圈主要国家（地区）中小学母语教育教学资源建设状况调查与研究”（ZDI135-84);厦门大学人文社会科学重大项目培育计划“世界主要国家母语能力要求及其语言资源建设研究 ”20720191075
A Differentiation of the “Desires” in Mencius's “Few Desires”from the Perspective of Discourse Analysis
No full text徐朝旭,厦门大学哲学系教授、博士生导师；蔡春良,厦门大学哲学系博士研究生。【中文摘要】历代学者对孟子“寡欲”之“欲”的内涵有三种诠释：中性说、善恶混合说、私欲说。将三种诠释分别代入孟子的“养心莫善于寡欲”命题并进行话语分析,可以得出三种不同的结论。中性说认为孟子“养心”就是任何时候都要最大程度地压制和减少生存之欲，这有违孟子以道作为取舍欲望的根本标准，也与孟子的生活经历不符。混合说虽然在义理上可以成立，但与孟子教化世人之欲望的处置方式不符，故与孟子思想存在差异。只有私欲说才与孟子的思想体系和实际生活相一致,并符合儒家工夫论的逻辑进路与具体实践，可见孟子“寡欲”之“欲”指的是私欲。厘清孟子“寡欲”观的思想内涵，不仅有助于了解儒家理欲学说的发展脉络，而且对于生态危机背景下正确认识道德与欲望的关系具有重要意义。
【Abstract】There are three interpretations of the connotation of the “desires” in Mencius's “few desires”:the neutral theory，the good - and - evil mixed theory，and the selfish - desires theory. If we place them into Mencius's proposition that “to nourish the mind there is nothing better than having few desires”，and conduct a discourse analysis，we will come to three different conclusions: The neutral theory will lead to the conclusion that Mencius's “nourishing the mind” is to suppress and minimize the desires for survival at all times，which is contrary to Mencius's fundamental standard of basing his choice of desires on Tao，and is inconsistent with Mencius's life experience. Although the mixed theory can be established in the determinations of righteousness and the principles of our nature，it is incongruous with Mencius's way of enlightening people on how to deal with their desires，and therefore is different from Mencius's thought.Only the selfish-desires theory is consistent with Mencius's thought system and actual life and conforms to the logic approach and concrete practice of the Confucian theory of cultivation. Therefore，the “desires” in Mencius's “few desires” refer to selfish desires. To clarify the ideological connotation of Mencius's concept of “few desires” is not only helpful for understanding the development of Confucian theory of the principles of our nature and desires，but also of great significance for correctly nderstanding the relationship between morality and desires in the context of ecological crisis
Corporate Innovation Investment Policy and Liquidity Management
No full text陈蓉，厦门大学经济学院/管理学院教授、博士生导师，经济学博士；左玲，厦门大学经济学院博士研究生；郑振龙，厦门大学管理学院教授、博士生导师，经济学博士。【中文摘要】创新投资是企业提升竞争力和创造高额利润的关键所在,对于企业的发展至关重要。基于企业的创新项目成功的概率分布难以预测的事实,拓展了现有研究框架，在引入模糊性的情形下构建最优决策模型，研究了企业的动态创新投资策略和流动性管理策略。数值结果发现:引入模糊性后，企业创新投资策略更加符合实际和经济学直觉;当企业面临的融资约束较弱时，模糊厌恶增加使企业放大外部不确定性对创新投资的影口向,从而减少创新投资和实物投资，最终导致企业价值降低,而当面临的融资约束非常强时，企业的创新投资主要由融资约束决定，模糊厌恶对其影响较小；模糊厌恶增加促使企业降低现金持有，加速分红，发行较少的股权融资数额及选择较高的信贷额度。
【Abstract】 Given the difficulty of predicting the success probability distribution of enterprise innovation projects,we expand the existing research framework,build an optimal decision model with the introduction of ambiguity, and study the dynamic innovation investment policy and liquidity management policy of enterprises. Numerical results show that enterprise innovation investment policy is more in line with the reality and economic intuition after the introduction of ambiguity. When the enterprise faces less financing constraints,ambiguity aversion amplifies the effect of external uncertainty on innovation investment and the enterprise will reduce innovation investment and physical investment,leading to a lower value of the firm,but when the enterprise faces very strong financing constraints,innovation investment is mainly determined by financing constraints,and ambiguity aversion has little effect on it;the increase of ambiguity aversion prompts the enterprise to reduce cash holdings,speed up dividends,issue less equity financing,and opt for higher credit lines.国家自然科学基金面上项目“波动率微笑：隐含信息与动态建模”（71471155)；国家自然科学基金面上项目“衍生品市场隐含的投资者情绪：提取、分析与应用”（71871190)；国家自然科学基金重大项目“中国制度与文化背景下公司财务政策的理论与实践研究” (71790601
On the Supporting Functions of Standards for Law
No full text柳经纬，中国政法大学比较法学研究院教授、博士生导师，中国标准化专家委员会委员。【中文摘要】标准是标准化机构制定的技术规范，其对法律具有重要的支撑作用。这种作用主要表现在三个层面:一是在作用的机制上，标准具有延伸法律调整社会关系的作用，解决了法律无法直接回答的“如何为”的问题;二是在作用的广度上，标准对法律所起的作用是全领域的，在绝大多数的法律领域里均可以发现标准的存在;三是在作用的力度上,法律对标准形成了依赖关系，在许多法律领域里，法律离开标准将难以发挥作用。标准对法律的支撑作用表明，在全面依法治国、建设法治国家的进程中，应当高度重视标准的作用，将标准纳入法治的视野，统揽标准和法律两个方面,充分发挥标准在法治中的作用。
【Abstract】Standards are technical regulations developed by the Standards Development Organization (SDO)，playing
an important supporting role in law. And this role mainly focuses on three aspects: The first is the mechanism of functions， which extends the functions of law in regulating social relations and solves the problem that the law cannot answer directly is “how to do”. The second is the extent of functions，as the supporting functions of standards for law are all - encompassing and standards can be found in almost any area of law. The third is the strength of functions，as the law has formed dependence on standards. In many legal areas，it will be difficult for the law to work its effect without the support of standards. The supporting functions of standards to law indicate that we should think highly of the function of standards and integrating standarrs into the legal system and combining standards and law to realize the full play of the supporting functions of standards for law in the process of implementing the notion of governing the country by law in all respects and establishing governance by law in our country.国家社会科学基金项目“标准的私法效力研究”（19BFX117
Structures and Electrochemical Properties of Sn-Cl Co-Doped Li2MnO3 as Positive Materials for Lithium Ion Batteries
No full text以乙酸盐为原料，柠檬酸为络合剂，通过溶胶-凝胶的方法制备富锂阴极材料Li2MnO3，选用草酸亚锡(SnC2O4)为锡源，用Sn4+代替Mn4+，获得不同掺杂量的材料. 适当含量的Sn4+掺杂可以提高材料的放电比容量，在低电流下获得256.3 mAh·g-1的高放电比容量，但由于Sn4+离子半径过大，不能起到稳定结构的作用，材料的倍率性能较差. 在此基础上，选用氯化亚锡(SnCl2)进行掺杂改性，在材料中同时引入Sn4+和Cl-掺杂，获得了层状结构更完整的粉末样品. 通过共掺杂改性的阴极材料可以在20 mA·g-1的电流密度，经过80圈的循环仍然保持153 mAh·g-1的放电比容量，且此时还未出现衰减现象，库仑效率保持在96%以上；在400 mA·g-1的电流密度下提供的比容量可高达116 mAh·g-1，是未掺杂样品的2倍左右.Positive material Li2MnO3 shows the highest ratio of lithium to manganese among lithium-rich materials and exhibites the theoretical capacity up to 458 mAh·g-1, making it one of the most promising cathode materials. However, this material has the intrinsic low electrical conductivity and poor cycle stability. In this paper, Li2MnO3, the lithium-rich positive material, was prepared by sol-gel method using acetate as raw material and citric acid as a complexing agent. By using SnC2O4 as a tin source, Sn4+ instead of Mn4+ was introduced to obtain the materials with different doping amounts. The resultant solution was evaporated at 80 °C under vigorous stirring to get a viscous gel. Next, the resulting gel was dried at 120 °C for 12 h. Finally, the gathered precursor was calcined at 600 °C for 6 h under an air atmosphere to obtain the target material. It was found that the proper content of Sn4+ doping could increase the specific discharge capacity of the material, obtaining as high as 256.3 mAh·g-1 at low current, but had a detrimental influence on the rate performance. On this basis, SnCl2 was used for doping modification, and the Sn4+ and Cl- co-doping into Li2MnO3 revealed a better developed layered structure with high conductivity. The intensity of super lattice peak formed between 2θ = 20° and 30° was increased by Cl-doping, indicating the ordered Li/Mn in the TM layer. Especially, this Sn-Cl co-doped Li2MnO3 sample delivered the relatively high specific discharge capacity of approximate 160 mAh·g-1 after 80 cycles at 20 mA·g-1. At the high current density of 400 mA·g-1, this material provided the specific discharge capacity of 116 mAh·g-1, which is about twice that of the undoped sample.国家重点研发计划(No. 2016YFB0300801)和国家自然科学基金重大科研仪器设备研制专项(No. 51327902)资助作者联系地址：1. 中南大学粉末冶金研究院，湖南 长沙 410083；2. 中南大学粉末冶金国家重点实验室，湖南 长沙 410083Author's Address: 1. Powder Metallurgy Research Institute, Central South University, Changsha 410083, China; 2. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China通讯作者E-mail：[email protected]
Insight into the Important Solid/Liquid Double Layer from First-Principles Calculations
No full text固液界面双电层在电化学中处于核心地位. 如何发展一个理论方法，在该方法的框架下计算双电层的平衡性质和动力学性质一直以来都是理论研究的难点和热点. 本文总结了最近十几年第一性原理计算方法在计算双电层平衡性质和电催化反应的进展，如热力学方法、反应中心模型以及双参考方法. 并进一步详细地阐述了基于周期性均匀介质溶剂化模型 ( DFT/CM-MPB)对于固液界面双电层的研究，该方法能够计算双电层的平衡性质(零电荷电势和微分电容)和表面相图，在此基础上能深入研究基元反应的电荷转移系数，并结合微观动力学推导出宏观的Tafel(电流-电势)曲线. 并列举了该方法对于重要电化学反应(如氢电极反应)的应用实例.Solid/liquid double layer is of fundamental importance in electrochemistry. It has been a challenge and focus to understand the equilibrium and the dynamic phenomena (e.g., chemical reactions) at the electrode/electrolyte double layer in a unified theoretical framework. In recent years, rapid expansion and development have been done in the application of first principles density function theory (DFT) simulation on the double layer. This article reviews the current theoretical methods for electrochemistry modeling, such as reaction center model, thermodynamic method and double reference model. The progress in the computation procedures based on first principles periodic continuum solvation method (DFT/CM-MPB) for obtaining the differential capacitance, surface phase, charge transfer coefficient (CTC) and deducing the potential-dependent reaction rate are summarized in detail. Representative reactions, namely, hydrogen evolution reactions, are selected to illustrate how the theoretical methods are applied to compute quantitatively the kinetics of multiple-step electrochemical reactions.国家自然科学基金项目（NO.21573149, NO.21533001, NO.91745201）资助作者联系地址：1. 上海应用技术大学，上海 201418； 2. 复旦大学，上海 200433Author's Address: 1. School of Chemical and Environmental Engineering, Shanghai Institute of Technology, Shanghai 201418, China; 2. Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Key Laboratory of Computational Physical Science Ministry of Education,Fudan University, Shanghai 200433, China通讯作者E-mail：[email protected]
Encouraging More Frogs in Electrochemistry
No full text作者联系地址：1. 合肥微尺度物质科学国家研究中心，中国科学技术大学化学物理系，安徽 合肥 230026； 2. 乌尔姆大学理论化学研究所，德国乌尔姆市，89069；3. 厦门大学化学化工学院，福建 厦门 361005Author's Address: 1. Hefei National Laboratory for Physical Sciences at Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, China; 2. Institute of Theoretical Chemistry,Ulm University, Ulm, Germany, 89069; 3. Department of Chemistry, Xiamen University, Xiamen, 361005, Chin
On the Construction of “Diversity and Integration” in the Global Financial Governance Mechanism
No full text李国安，厦门大学法学院教授、博士生导师。【中文摘要】全球金融利益分配与博弈是全球金融治理体系构建的核心，也是现行全球金融治理体系存在治理主体和治理法制碎片化、治理体制缺乏有效的国际协调与合作、国际金融组织的权责机制对发展中国家的不公平与不合理等弊端之根源。尽管新兴经济体为全球金融治理秩序的修复进行了一系列有益尝试,但区域性与辅助性的基本定位决定了其无法对现有全球金融治理体系形成实质性挑战。国际社会应树立“共同发展”的全球金融治理理念，凝聚已有治理机构和治理法制的长处，沿循国际政治与法律的路径,构建“多元一体”的全球金融治理体系。
【Abstract】 The distribution and game of global financial interests is the core of the construction of a global financial governance mechanism，and it is also the root of the drawbacks of the existing global financial governance system，including the fragmentation of governance subjects and governance rule of law，lack of effective international mechanisms for governance coordination and cooperation，and the unfairness and irrationality of the power and responsibility mechanisms of international financial organizations for developing countries.Although emerging economies have made a series of useful attempts to rectify the global financial governance order， their basic regional and auxiliary positioning determines that they cannot present a substantive challenge to the existing global financial governance system. Therefore，the international community should establish the concept of “common development” for global financial governance，consolidate the strengths of the existing governance institutions and governance laws，and follow the path of international politics and law to build a global financial governance mechanism featuring “diversity and integration”.福建省社会科学规划项目（省法学会专项）“金融科技的勃兴与监管科技运用的法律路径”(FJ2019TWFB05