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Uneven Urban-Rural Development and Its Transcendence:With a Focus on Das Kapital and Its Manuscripts
No full text林密，厦门大学马克思主义学院副教授，哲学博士。【中文摘要】城乡关系是马克思政治经济学批判及其当代化的重要议题。在《资本论》中，马克思告别早期泛分工论视域下的城乡对立观,从产业分工、劳动力空间流动、社会关系与社会基础服务体系的不平衡发展问题等视域，迈向了一种以生产方式同质化运动为基础的城乡不平衡发展观。马克思恩格斯坚持了主客体辩证统一的视角，立足于资本主义生产方式的历史起源与矛盾运动机制的历史科学分析，从大工业发展与城乡“对立”现象的内在关系、工农业实现更高阶段的融合以及土地国有化的历史必然性等角度,科学论证了人类社会告别城乡不平衡发展状态迈向城乡有机融合发展的历史必然性。
【Abstract】In Das Kapital，by grounding his viewpoints on the division of labor for industries，the spatial mobility labor and the unbalanced development between social relationships and the social fundamental service system，Marx moved from the view of urban-rural standoff based on generalized division theory to the view of uneven urban-rural development based on the homogenization movement of the mode of production. Marx and Engels adhered to the perspective of the dialectical unity of subject and object and conducted historical scientific analysis of the origin and contradiction movement mechanism of the capitalist mode of production. Their analysis was conducted in terms of the intrinsic relationship between the development of large industry and the urban-rural “standoff”，the integration of industry and agriculture at a higher stage，and the historical inevitability of land nationalization. They scientifically demonstrated the historical inevitability for human society to bid farewell to uneven urban-rural development and march towards organic urban-rural integration.国家社会科学基金一般项目“马克思政治经济批判视域中的城乡不平衡发展问题研究”（19BZX018）
Construction of a Stock Market Liquidity Comprehensive Index and Liquidity Premium Test:An Empirical Study Based on High-Frequency A-Shares Data
No full text陈海强，厦门大学经济学院/王亚南经济研究院教授、博士生导师；姜盼，厦门大学经济学院博士研究生。【中文摘要】对流动性溢价的检验是资产定价理论和实证研究关注的重要问题。已有文献对A股流动性的测度比较单一,影响了结论的可靠性。基于2007年1月至2016年12月A股高频交易数据,使用主成分分析方法，可构造一种新的流动性综合指标来检验流动性对股票收益率的影口向。分组分析和回归分析的结果显示,A股市场存在流动性溢价效应，支持流动性溢价理论。同时，基于该流动性综合指标所建立的流动性风险因子模型对投资组合超额收益率的解释能力优于传统定价模型。研究结果也表明,换手率更多反映的是股市投机气氛，并不适合做流动性的代理指标。
【Abstract】The test of liquidity premium is an important issue in asset pricing theory and empirical research.The existing literature has a limited measure of A-shares liquidity，affecting the reliability of its conclusions. High - frequency data of A-shares in China from January 2007 to December 2016 were selected to test the impact of liquidity on stock returns. Based on the high - frequency trading data of A-shares and using the principal component analysis method，a new liquidity comprehensive index is constructed. Through grouping analysis and regression analysis，it is found that liquidity premium effect exists in the A-shares market，which supports liquidity premium theory.The liquidity risk factor model is established based on the liquidity comprehensive index，which is more effective than the traditional pricing model in explaining the excess return of investment portfolios. Furthermore，it is found that the turnover rate largely reflects the speculative atmosphere in the stock market and is unsuitable to serve as a liquidity proxy indicator.国家自然科学基金“基于面板数据的政策评估方法:计量理论与应用”（71571152);国家自然科学基金“金融科技背景下非正规金融机制设计、风险防范与治理”（71850011
Study of China's Policy Implementation Effectiveness Audits:Based on the Construction of the Index System for Policy Implementation Effectiveness Evaluation
No full text张龙平，中南财经政法大学会计学院教授、博士生导师，经济学博士 ；熊雪梅,中南财经政法大学会计学院博士研究生。【中文摘要】审计监督职能的优化与拓展促使国家审计在推动国家政策贯彻落实上发挥更大作用，在实践中强化对政策执行效果的评价有助于政府受托责任的有效履行。针对目前审计过程中政策执行效果评价缺乏较为统一标准的现状，构建更为完整且可操作性更强的评价指标体系意义重大。根据政策执行效果审计具有绩效审计和跟踪审计的特点,政策评价指标体系的构建主要有过程观和目标观两种思路。在此基础上，运用层次分析法，可构建较为完整科学的总目标层为政策执行效果指数的政策评价指标体系。该体系一级指标为过程与目标两个分项，二级指标分别为过程分项的四个指标(政策制定、政策执行、政策监督与政策反馈）和目标分项的三个指标(经济效益、社会效益与政治效益），并在此基础上进一步展开三级指标和四级指标。政策执行效果评价指标体系的构建为促进政策执行效果审计高效发挥监督作用提供了较为全面且可行的评价方式，顺应了我国在重大政策措施贯彻落实方面增强审计力度的部署要求。
【Abstract】The optimization and expansion of the audit supervisory function has prompted national audits to play a greater role in pushing forward the implementation of national policies. Strengthening the evaluation of the effect of policy implementation in practice is conducive to the effective fulfillment of public accountability. In view of the lack of uniform standards for evaluating policy implementation effectiveness in the current audit process，it is crucial to construct a more complete and operable evaluation index system. Policy implementation effectiveness audits share the characteristics of performance audits and real-time audits; therefore，the policy evaluation index system mainly includes process view and target view. On this basis，we apply the analytic hierarchy process to construct a more complete and scientific multi-level indicator system for evaluating the effect of policy implementation. The first level is divided into process and target，and the second level indexes include four process components (policy development，policy implementation，policy surveillance and policy feedback) and three target components (economic benefit，social benefit and political benefit). The third and fourth levels of indicators are further developed on this basis. In sum，the system provides a comprehensive and feasible evaluation method to further enhance the supervisory function of policy implementation effectiveness audits，and adapts to the nation's requirements for strengthening the audits of the implementation effectiveness of major policies
Electrocatalytic reduction of CO2 to ethylene and ethanol through hydrogen-assisted C-C coupling over fluorine-modified copper
Get PDF精准控制C1分子C-C偶联合成特定C2+化合物是C1化学中极具挑战性的难题。由于C2+化合物(如乙烯和乙醇)在化工和能源领域具有重要用途，将CO2直接转化为C2+产物极具吸引力。发展高效催化剂，实现高电流密度、高C2+选择性、高稳定性的“三高”性能，是推进电催化还原CO2走向实际应用的关键。研究团队针对电催化还原CO2中高CO2还原法拉第效率的催化剂常常活性低的问题，提出了适当提高催化剂活化水的能力对增加CO2还原活性的重要性，发展出氢助碳碳偶联(hydrogen-assisted C-C coupling)的新策略，在氟修饰的铜(F-Cu)催化剂上实现了CO2电催化还原制乙烯和乙醇的新突破。该研究工作实验部分主要由王野、张庆红教授指导，能源材料协同创新中心iChEM2016级博士生马文超、固体表面物理化学国家重点实验室高级工程师谢顺吉(共同第一作者)完成；理论计算部分由程俊教授指导，2017级硕士生刘彤彤(共同第一作者)、2016级博士生樊祺源完成。叶进裕博士为原位红外测试提供了支持。上海光源姜政研究员、孙凡飞博士、杨若欧为同步辐射表征提供了支持。
这是投稿的最终版本，正式出版的论文版本请访问官方链接（https://doi.org/10.1038/s41929-020-0450-0）。Electrocatalytic reduction of CO2 into multi-carbon (C2+) products is a highly attractive route for CO2 utilization. However, the yield of C2+ products remains low because of the limited C2+ selectivity at high CO2 conversion rate. Here, we report a fluorine-modified copper catalyst that exhibits an ultrahigh current density of 1.6 A cm−2 at C2+ (mainly ethylene and ethanol) Faradaic efficiency of 80% for electrocatalytic CO2 reduction in a flow cell. The C2-4 selectivity reaches 85.8% at a single-pass yield of 16.5%. We show a hydrogen-assisted C−C coupling mechanism between adsorbed formyl (CHO) intermediates for C2+ formation. Fluorine enhances water activation, CO adsorption and hydrogenation of adsorbed CO to CHO intermediate that can readily undergo coupling. Our findings offer an opportunity to design highly active and selective CO2 electroreduction catalysts with potential for practical applicationThis work was supported by the National Key Research and Development Program of the Ministry of Science and Technology of China (No. 2017YFB0602201), the National Natural Science Foundation of China (Nos. 21690082, 91545203, 21503176 and 21802110), We thank staffs at the BL14W1 beamline of the Shanghai Synchrotron Radiation Facilities (SSRF) for assistance with the EXAFS measurements.研究工作得到科技部重点研发计划（批准号：2017YFB0602201）和国家自然科学基金（批准号：21690082、91545203、21503176、21802110）项目的资助
Surface-enhanced Raman spectroscopy: benefits, trade-offs and future developments
No full text任斌教授课题组一直致力发展PERS新方法和仪器。此综述课题组在介绍SERS基本原理的基础上，从分子与纳米材料作用的本质入手，分析如何提高SERS实验的重现性以及如何规范的计算SERS增强因子。特别为读者给出未来SERS应用于实际样品的定量分析所必须遵循的实验设计思路和原则。Surface-enhanced Raman spectroscopy (SERS) is a vibrational spectroscopy technique with sensitivity down to the single molecule level that provides fine molecular fingerprints, allowing for direct identification of target analytes. Extensive theoretical and experimental research, together with continuous development of nanotechnology, has significantly broadened the scope of SERS and made it a hot research field in chemistry, physics, materials, biomedicine, and so on. However, SERS has not been developed into a routine analytical technique, and continuous efforts have been made to address the problems preventing its real-world application. The present minireview focuses on analyzing current and potential strategies to tackle problems and realize the SERS performance necessary for translation to practical applications.The authors acknowledge support from NSFC (21790354, 21633005, and 41876099) and MOST of China (2016YFA0200601), National Key Research & Development Program of China (No. 2018YFC1602600, 2018YFC0807201). Ana Isabel Pérez-Jiménez acknowledges the support from Xiamen University for her the postdoctoral fellowship. Danya Lyu acknowledges the support from the postdoctoral science foundation (2019M662230). Thanks Matthew Sartin for the editing
Latest and Hot Papers
No full text通讯作者:詹东平E-mail:[email protected]:ZHANDong-pingE-mail:[email protected]厦门大学化学化工学院College of Chemistry and Chemical Engineering, Xiamen Universit
A Simple and Sensitive Aptamer-Based Electrochmical Sensor for Determination of Aflatoxin B1
No full text黄曲霉毒素B1（AFB1）以其高毒性和致癌性成为食品安全隐患而备受关注. 本文拟构建一种新颖、简单、快速、灵敏的传感器用于谷物食品中AFB1的痕量检测. 将介孔碳（CMK）修饰在工作电极表面来增大电极的表面积,再将工作电极恒电位沉积金纳米粒子（AuNPs）,提高电信号的同时,为下一步巯基化适配体的连接提供位点. 检测过程中,AFB1可以竞争性地去除吸附在适配体链上的亚甲基蓝（MB）引起电信号的变化,对AFB1进行定量检测. 修饰的工作电极导电性能得到改善,灵敏度大大提高,对AFB1的线性响应范围为0.1 ~ 75 μg·L-1,检出限低至36 ng·L-1. 在对不同谷物食品（大米、玉米、糯米）进行加标回收实验中,回收率在92.3% ~ 103.6%范围之间,实现对目标物的定量检测. 本文为食品中AFB1快速检测方法提供了一种新思路和新方法.Aflatoxin B1 has attracted much attention because of its high toxicity and carcinogenicity, which has become a great concern in food safety. Based on the principle of specific binding between Aflatoxin B1 and its aptamer, an aptamer-based electrochemical sensor had been designed and developed for the determination of minor Aflatoxin B1 contained in grain. The mesoporous carbons were first modified on the surface of the working electrode, and then the gold nanoparticles were on-site electrodeposited at a constant potential. Each modified electrode was characteritised by scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). As a result, the surface area and the electrochemical signal of the modified electrode were all greatly increased, providing more attachment sites for the following conjugation of the aptamer. During the detecting process, Aflatoxin B1 could compete with methylene blue on the aptamer chain to cause methylene blue shedding and the electrochemical signals were changed which could be used to quantify the concentration of Aflatoxin B1. The surface modifications could evidently improve the conductivity and sensitivity of the sensor. A linear response in current to Aflatoxin B1 was found ranging from 0.1 to 75 μg·L-1 with the detection limit as low as 36 ng·L-1 (S/N = 3). The spiked recovery tests of different grains (rice, corn, glutinous rice) revealed that the recovery rates were between 92.3 and 103.6%, showing excellent accuracy, sensitive quantitative detection of the target substance and good reproducibility. This work has demonstrated a new method to develop a novel, simple, fast and sensitive sensor for the detection of trace amount of Aflatoxin B1 in grains.国家重点研发计划项目（No.2018YFC1604000）资助通讯作者:刘冰,王硕E-mail:[email protected]:LIUBing,WANGShuoE-mail:[email protected]. 食品营养与安全国家重点实验室,食品营养与安全教育部重点实验室,天津 3004572. 天津科技大学食品科学与工程学院,天津 3004571. State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Food Nutrition and Safety,Ministry of Education, Tianjin 300457, China2. College of Food Science and Technology, Tianjin University of Science and Technology, Tianjin 300457, Chin
Research Progresses of Copper Interconnection in Chips
No full text本文详细介绍芯片制造中铜互连技术,综述酸性硫酸铜电镀工艺要点及常用添加剂作用机理,并概述国内外新型添加剂研究进展. 在此基础上,展望新型铜互连工艺替代酸性硫酸电镀铜工艺的可能性.In this paper, the copper interconnection technology in chip manufacturing is introduced in detail, and the essentials of acidic copper sulfate electroplating process and the mechanisms of common-used additives are reviewed. The progresses of novel additives at home and abroad are also summarized. Based on the studied achievement, the possibility of the novel copper interconnect process replacing the acidic copper electroplating is prospected.国家自然科学基金项目资助(21972118);国家自然科学基金项目资助(21827802)通讯作者:杨防祖,詹东平E-mail:[email protected];[email protected]:YANGFang-zu,ZHANDong-pingE-mail:[email protected];[email protected]固体表面物理化学国家重点实验室,厦门大学化学化工学院,福建 厦门 361005College of Chemistry and Chemical Engineering, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005, Fujian, Chin
Fuel Cell Performance of Non-Precious Metal Based Electrocatalysts
No full text国家重点研发计划新能源汽车重点专项(2017YFB0102900);国家重点研发计划新能源汽车重点专项(2018YFB0105700);佛山市香港科技大学产学研合作专项(FSUST19-FYTRI07);广东省基础与应用基础研究基金区域联合基金-青年基金项目资助(2019A1515110253)通讯作者:邵敏华E-mail:[email protected]:SHAOMin-huaE-mail:[email protected].江苏奥新新能源汽车有限公司，江苏 盐城 2240002.香港科技大学化学及生物工程系，香港 九龙清水湾3.上海智能新能源汽车科创功能平台有限公司，上海 2018054.长三角新能源汽车研究院有限公司，江苏 盐城5.广州市香港科大霍英东研究院，广东 广州 5114586.香港科技大学能源研究院，香港 9990771. Jiangsu Aoxin NEV Co., Ltd, Yancheng, Jiangsu, 224000, China2. Department of Chemical and Biological Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China3. Shanghai AI NEV Innovative Platform Co., Ltd, Shanghai, 201805, China4. Yangtse Delta Academy of NEV CO.,LTD, Yancheng, Jiangsu, 224000, China5. Fok Ying Tung Research Institute, The Hong Kong University of Science and Technology, Guangzhou 511458, China6. Energy Institute, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, Chin
Cycling Performance and Solid-Electrolyte-Interphase Synergic Formation of Silicon Nanoparticles in the Concentrated Electrolyte with Additives
Get PDF本文研究了在LiFSI-(PC)3高浓度电解液中添加剂对于纳米硅材料的循环性能的影响,采用扫描电子显微镜、傅里叶变换红外光谱和X-射线光电子能谱分析了循环过程纳米硅材料及其电极的结构和表面SEI膜演化的特征. 结果表明,添加剂能够改善纳米硅材料的循环性能,在LiFSI-(PC)3高浓度电解液中循环300周材料比容量为574.8 mAh·g-1,而含有3%LiDFOB、3%FEC、3%TMSB的添加剂的高浓度电解液中,比容量分别为1142.9、1863.6和1852.2 mAh·g-1. 作者分析认为,在LiFSI-(PC)3浓溶液中LiFSI优先于PC在纳米硅表面发生成膜反应,形成的SEI膜由以无机物主导的内层膜和以有机物主导的外层膜组成,而在含添加剂的高浓度电解液中,添加剂和LiFSI协同参与SEI成膜反应,形成的内层膜能够减缓PC溶剂参与外层的成膜反应,由此形成的SEI膜能够抑制循环过程中SEI膜的过度生长,更好地抑制了纳米硅的粉化,纳米硅材料及其电极结构稳定性更好,材料表现出更好的循环性能.In this paper, the effects of additives on the cycling performance of silicon nanoparticles in LiFSI-(PC)3 based concentrated electrolytes were systematically studied. The structures of silicon nanoparticle electrodes and the evolution of solid-electrolyte-interphase were characterized by scanning electron microscopy (SEM）, attenuated total reflection Flourier transformed infrared spectroscopy (ATR-FTIR） and X-ray photoelectron spectroscopy (XPS). The results indicated that the additives can efficiently improve the cycling performance of silicon nanoparticle electrodes. In LiFSI-(PC)3 concentrated electrolyte, the capacity became 574.8 mAh·g-1 after 300 cycles with the initial capacity of 3296.1 mAh·g-1. In contrast, the 3% LiDFOB, 3% FEC and 3% TMSB-containing systems reached 1142.9, 1863.6 and 1852.2 mAh·g-1 after 300 cycles, respectively. The comprehensive analysis indicates that the reduction of LiFSI takes priority over PC on the surface of silicon nanoparticles in LiFSI-(PC)3 concentrated electrolyte, and the SEI film is composed of an inner layer dominated by inorganic products and an outer layer dominated by organic products. While in the concentrated electrolyte containing additives, the additives and LiFSI participate in the formation of SEI inner layer synergistically, and the SEI inner layer can suppress the reduction of PC which contribute to the formation of SEI outer layer. The SEI film formed on this mechanism could suppress the excessive growth of the SEI film, mitigate the pulverization of silicon nanoparticles, and enhance the structure stability of the silicon nanoparticle electrode, thus, the silicon nanoparticle electrodes exhibited better cycling performance.国家重点研发计划项目(2016YFB0301305);国家重点研发计划项目(2018YFB0104400);国家自然科学基金项目(U1764255);国家自然科学基金项目(21903067)通讯作者:卢世刚E-mail:[email protected]:LUShi-gangE-mail:[email protected].有研科技集团有限公司_国家动力电池创新中心,北京 1000882.国联汽车动力电池研究院有限责任公司,北京 1000883.北京有色金属研究总院,北京 1000881. National Power Battery Innovation Center , GRINM Group Corporation Limited, Beijing 100088, China2. China Automotive Battery Research Institute Co., Ltd., Beijing 100088, China3. General Research Institute for Nonferrous Metals, Beijing 100088, Chin