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Historiography Thoughts and Achievement of Han Guopan
No full text郑学檬，厦门大学历史系教授、博士生导师；陈明光，厦门大学历史系教授、博士生导师；杨际平，厦门大学历史系教授、博士生导师；毛蕾，厦门大学历史系副教授。【中文摘要】韩国磐是中华人民共和国成立之后声名鹊起的著名历史学家，是20世纪五六十年代马克思主义史学在中国骎替传统史学过程中涌现的中国古代史研究名家代表之一。从近70年来中国历史学的演进过程中考察韩先生的治学道路,其史学成就体现在包举大端、把握全局的整体史观，钩沉索隐、辩证史实的治学风格，以及在新时代中更新“史识”等三方面。历史需要反复认识，对各个历史时期中国史学取得的丰富成果和矫枉过正之偏作出客观的学术总结，有利于发扬光大我国传统史学的精华，加快构建中国特色历史学学科体系、学术体系、话语体系。
【Abstract】Han Guopan (1919-2003 )，a prominent historian of New China，was well known in the 1950s-60s when
Marxism historiography was exerting a significant impact on traditional Chinese historiography. Reviewing his research experience within the development process of Chinese history in New China，we conclude that his academic achievements include holistic viewpoints，textual and dialectical methodology，and revising research approaches in the new era. History needs repeated cognition. It will help promote the inheritance and development of our brilliant historiography tradition，and they may also help “accelerate the construction of historical disciplinary system，academic system and discourse system with Chinese characteristics”
Does Local Audit Officers' Tenure Affect the Efficiency of National Audits?: Evidence from the Preservation and Appreciation of State-owned Assets
No full text王艳艳,厦门大学管理学院教授、博士生导甲，管理学博士；王迪，厦门大学管理学院博士研究生；李文涛，厦门大学管理学院博士研究生。【中文摘要】我国公有制经济在国民经济中的主导地位决定了国家审计在整个审计体系中的重要性。国家审计机关通过对国有企业进行审计，发挥其保障国有资产保值增值的职能作用。基于国家审计视角，以2007—2016年我国A股上市公司为研究样本,通过手工收集地方审计厅厅长任职和个人履历信息，检验了地方审计官员任期对国有资产保值增值的影响。研究发现:地方审计厅厅长的任期越长,国有资产保值增值率越低。上述关系受审计厅厅长任期特征、个人特征和被审计企业政治关系特征的影响。进一步检验表明，随地方审计厅厅长任期的增加，地方国企的过度投资、在职消费和盈余管理程度均显著提高,从而影响国有资产保值增值目标的实现。
【Abstract】 The dominance of public economy in China determines the importance of national audits in the entire auditing system. The national audit office plays its role of ensuring the preservation and appreciation of state-owned assets through auditing SOEs. Based on China's A-share listed companies in the period 2007-2016，with hand-collected information on officers’ tenures and careers，we examine how local audit officers’ tenure affects the preservation and appreciation of state-owned assets. We find that longer local audit officers’ tenure tends to result in weaker preservation and appreciation of state-owned assets.This relationship is affected by audit officers’ job characteristics and personal characteristics ，as well as audited firms’ political relationship characteristics.Additional tests also reveal that as local audit officers’tenure extends，local SOEs’ over-investment，perk consumption and earning management increase，resulting in the loss of state-owned assets.国家自然科学基金面上项目“新兴媒体环境下资本市场信息披露问题研究”（71572163);国家自然科学基金重点项目“金融政策对企业投融资行为的影响研究”（71532012);国家自然科学基金面上项目“信息披露对实体经济发展的影响机制研究”（71972161);国家自然科学基金面上项目“会计准则视角下银行系统性风险影响机制研究（71972162)”；国家自然科学基金重大项目“中国制度和文化背景下公司财务政策的理论与实践研究” (71790601);“国家万人计划”青年拔尖人才；中央高校基本科研业务费专项资金资助项目“走出去战略下的会计师事务所内部治理机制研究” (20720191087
Observing atomic layer electrodeposition on single nanocrystals surface by dark field spectroscopy
Get PDF从单颗粒水平研究电化学表面和界面过程，特别是欠电位沉积是电化学领域的一个重要挑战。欠电位沉积通常仅涉及单原子层到亚单原子层的物种，但是能够显著调控金属表面电子结构，是制备高效电催化剂的一个重要的方法。然而目前在电化学环境下表征单个粒子表面单层原子的变化仍然是个巨大的挑战，针对上述挑战，任斌教授课题组发展了一套高灵敏的电化学暗场散射光谱装置，在不使用特殊光源的情况下，可以使得检测的粒径小至10-15 nm，灵敏度提高到亚单层原子。该工作是在任斌教授指导下，主要由化学化工学院已毕业博士生胡树（第一作者）完成。李剑锋教授及其课题组的博士生张月皎在单晶电化学实验上提供了重要帮助。已毕业博士生易骏在理论计算方面提供了有力支持。Underpotential deposition offers a predominant way to tailor the electronic structure of the catalytic surface at the atomic level, which is key to engineering materials with a high activity for (electro)catalysis. However, it remains challenging to precisely control and directly probe the underpotential deposition of a (sub)monolayer of atoms on nanoparticle surfaces. In this work, we in situ observe silver electrodeposited on gold nanocrystals surface from submonolayer to one monolayer by designing a highly sensitive electrochemical dark field scattering setup. The spectral variation is used to reconstruct the optical “cyclic voltammogram” of every single nanocrystal for understanding the underpotential deposition process on nanocrystals, which cannot be achieved by any other methods but are essential for creating novel nanomaterials.The authors thank Dr. Hai-Xin Lin for helpful discussion of nanoparticle synthesis and characterization. The authors acknowledge support from the Natural Science Foundation of China (21633005, 21790354, and 21711530704) and the Ministry of Science and Technology of China (2016YFA0200601).该研究工作得到了国家自然科学基金委和科技部等的资助和支持
The Critical Spirit of Political Economy and the Value for the Era in Das Kapital:A Discussion on the Innovation of Marxist Political Economy in Contemporary China
No full text薛俊强，西南大学马克思主义学院教授,哲学博士。【中文摘要】《资本论》的政治经济学批判精神在于把既定社会关系下的经济、政治和文化现象纳入资本劳动的历史时空隧道中给予辩证审视，把政治经济学从作为财富生产与分配的古典形态转化为拷问经济生成规律的社会前提和人本价值的新政治经济学批判，把经济、政治和人的发展之间的关系作为思考的核心,深度追问经济问题背后的政治构架和价值前提。当前《资本论》研究应 从单向度批判与学术争鸣中走向积极建构，深度开展经济学、哲学和其他学科的跨学科对话，形成理论合力和学术共同体，彰显《资本论》解答时代问题的理论生命力和当代价值。中国马克思主义政治经济学理论创新只有秉持《资本论》的政治经济学批判精神,研究当代中国社会主要矛盾的结 构性社会机理,探索驾驭资本、创新国家和尊重劳动的经济制度安有才能书写出一部反映新时代 中国发展变化和解答时代之问的当代中国马克思主义政治经济学批判。
【Abstract】Current research on Das Kapital should be shift from one-sided criticism and academic debate to active construction. It should aim to carry out in-depth interdisciplinary dialogue among economics，philosophy and other disciplines ，in order to bring together theoretical synergy and academics and demonstrate the theoretical vitality and contemporary value of Das Kapital in answering the questions of the times. The critical spirit of political economy in Das Kapital is to bring the economic，political and cultural phenomena under established social relations into the historical time and space context of capital labor for dialectical examination，and to transform political economy from the classical form of wealth production and distribution into the social premise of examining the law of economic generation and the criticism of the new political economy of humanistic value. It takes the relationship between economy and politics and human development as the
core of thinking for deep inquiries into the political framework and value premise behind economic issues. In the theoretical innovation of Chinese Marxist political economy，only by adhering to the political and economic critical spirit of Das Kapital ，by studying the structural social mechanism of the principal contradictions in contemporary Chinese society，and by exploring the economic institutional arrangements for controlling capital，innovating the country and respecting labor，can we develop a critique of Marxist political economy in contemporary China that reflects the development and changes of China in the new era and answers the questions of the times.教育部人文社会科学基金青年项目“当代欧洲左翼政党价值观教育思想及其启示” (19YJC710063);重庆市社会科学规划基金博士基金项目“当代欧洲左翼政党价值观教育思想及其启示研究” (2018BS04);中央高校基本科研业务费专项资金资助项目“当代欧洲左翼政党价值观教育研究”（SWU1809718); 重庆市教委哲学社会科学重大理论研究阐释专项课题“马克思主义为什么行”（19SKZDX02
Transient enhancement and decoupling of carbon vs opal export in cyclonic eddies
No full textGiven their ephemeral nature, eddies have proven difficult to study, with contrary results from field observations that typically sample at the center during a specific stage of an eddy lifespan. Using the natural occurring radionuclide 234Th, we examined particle fluxes within two cyclonic eddies (CEs) at different evolutionary stages (mature stage eddy, C2, and a decay stage eddy, C1) in the oligotrophic western South China Sea (SCS). Using a 1-D steady state model, 234Th derived particulate organic carbon (POC) and opal fluxes at 100 m were determined. Both POC and opal fluxes were significantly higher at the eddy edge relative to the eddy cores, with integrated eddy POC and opal fluxes of 6.2 (2.1) mmol C m-2 d-1 and 1.5 (0.28) mmol Si m-2 d-1 in C2 (C1). When compared to non-eddy regimes, both POC (by 2.6-fold) and opal fluxes (by 7.5-fold) in C2 were enhanced; they were reduced and decoupled (0.9-fold and 1.4-fold) in C1. The difference in enhancement of particle fluxes and the coupling/decoupling between POC and opal flux likely reflects changes in phytoplankton community structures resulting from eddy evolution. Scaling these results to the entire SCS basin, suggests that CEs contribute 15% of the opal flux. Therefore, CEs may regulate the biogeochemical cycling of silica to a much greater extent than carbon in the ocean
Selective methylation of toluene using CO2 and H2 to para-xylene
Get PDF二甲苯（PX）是石化工业的基本有机化工原料之一，主要用于生产三大合成材料—合成树脂、合成纤维和合成橡胶。随着我国下游产业的快速发展，PX的需求量迅猛增长，进口依存度大于50%。袁友珠教授课题组提出使用CO2和H2替代甲醇作为甲苯烷基化试剂，利用CO2和H2在相对较低温度下生成的甲氧基中间体（无需经甲醇）直接与甲苯烷基化。化学化工学院2018级博士生左佳昌为论文第一作者，博士生陈伟坤、硕士生刘佳以及醇醚酯化工清洁生产国家工程实验室（厦门大学）段新平博士和叶林敏博士等参与了论文的部分研究。该研究结果已分别申请了中国发明专利（申请号201911149539.2, 2019）和国际专利（申请号PCT/CN2020/077412, 2020）。【Abstract】Toluene methylation with methanol to produce xylene has been widely investigated. A simultaneous side reaction of methanol-to-olefin over zeolites is hard to avoid, resulting in an unsatisfactory methylation efficiency. Here, CO2 and H2 replace methanol in toluene methylation over a class of ZnZrOx–ZSM-5 (ZZO-Z5) dual-functional catalysts. Results demonstrate that the reactive methylation species (H3CO*; * represents a surface species) are generated more easily by CO2 hydrogenation than by methanol dehydrogenation. Catalytic performance tests on a fixed-bed reactor show that 92.4% xylene selectivity in CO-free products and 70.8% para-xylene selectivity in xylene are obtained on each optimized catalyst. Isotope effects of H2/D2 and CO2/13CO2 indicate that xylene product is substantially generated from toluene methylation rather than disproportionation. A mechanism involving generation of reactive methylation species on ZZO by CO2 hydrogenation and migration of the methylation species to Z5 pore for the toluene methylation to form xylene is proposed.This work was supported by the National Key Research and Development Program of China (2017YFA0206801), the National Natural Science Foundation of China (21972113), and the Program for Innovative Research Team in Chinese Universities (IRT_14R31).该工作得到了国家重点研发计划（2017YFA0206801）、国家自然科学基金（21972113、91545115）和教育部创新团队（IRT_14R31）的资助
Syntheses and Properties of Ta 5+ Doped Li7La3Zr2O12
No full text本文采用固相法制备了Ta 5+掺杂的石榴石型无机固体电解质Li7-xLa3Zr2-xO12（xTa-LLZO）,研究了不同的掺杂量对材料性能的影响. 通过X射线发射光谱（XRD）、冷场发射电子扫描电镜（FESEM）和电化学阻抗（EIS）对材料进行物理表征和阻抗测试,并且组装LiFePO4//LLZTO//Li全固态锂电池测试电池的循环稳定性. 结果表明,随着Ta 5+掺杂的增加,材料呈现出一个单一的立方相结构,当Ta 5+掺杂量为14.09wt.%（即x=0.3）时,材料的室温离子电导率达到最大（2.58×10 -4 S·cm -1）,呈现出稳定的立方相结构且具有相对较高的致密度（89.16%）,并具有较稳定的循环稳定性,经过50个循环后容量保持率依然保持到88.67%左右.The tantalum ion (Ta 5+) doped garnet-type inorganic solid electrolyte Ta-LLZO was prepared by solid state reaction, and the effect of doping amount on the properties of the materials was investigated. The materials were characterized by X-ray diffraction (XRD), field emission electron scanning microscopy (FESEM) and electrochemical impedance spectroscopy (EIS). And the cycle stability was tested by assembly of LiFePO4//LLZTO//Li all solid lithium battery. The results show that with the increase of Ta 5+ doping amount, the material appeared to form a single cubic phase structure. When the Ta 5+ doping content became 14.09wt.%, x=0.3, the room temperature ionic conductivity of the material reached the maximum (2.58×10 -4 S·cm -1), forming a stable cubic phase structure with a relatively high density (89.16%). In addition, the relatively stable cycle stability was obtained and the capacity retention rate remained at around 88.67% after 50 cycles.国家自然科学基金项目(21766017);白银项目(2017-2-11G);中科院“西部之光”-西部青年学者项目通讯作者:李世友E-mail:[email protected]:LIShi-youE-mail:[email protected]兰州理工大学石油化工学院,甘肃 兰州 730050College of Petrochemical Technology, Lanzhou University of Technology, Lanzhou 730050, Chin
Materials, Micro-Stacks and Related Applications of Single-Chamber Solid Oxide Fuel Cells
No full text单气室固体氧化物燃料电池（SC-SOFC）是一种整个电池处在单一气室中,阳极和阴极分别对混合气体中的燃料和氧气进行选择催化产生电动势的特殊结构燃料电池. SC-SOFC因其独特的原理和结构而具有无需密封、易于堆叠、可以快速启动和不易发生积碳等诸多优点,有很大的应用潜力. 作者在SC-SOFC的原理和特点的基础上,系统地总结了SC-SOFC所用材料、微堆结构设计、衰退机制及应用方面的研究进展;以提高SC-SOFC微堆的输出电压和功率为目的,改进预混气体环境下运行的微堆结构,采取星型布局的四电池微堆其输出功率提高到420 mW;随后,逐步改进供气方式,结合计算流体力学数值模拟研究,提出了单路多点供气和双路多点供气模式,成功地将单个SC-SOFC微堆模块的输出功率提升到8.178 W,进而开展了微堆模块外部串并联和与燃烧器的结合实验验证. 研究结果表明,SC-SOFC可以很便捷地连接成微堆模块并产生数瓦的输出功率,未来有望用于以供热为主型的热电联供系统. 作者还借助原位电阻和开路电压的原位同步测试,阐明了Ni在CH4-O2气氛中的反复氧化-还原循环是SC-SOFC发生不可逆衰退的主要机制,这一发现后来催生出氧化-还原法制备多孔金属的新技术.Single-chamber solid oxide fuel cell (SC-SOFC) is a special type of fuel cells, in which both an anode and a cathode are placed in one chamber. Its working principle relies on the selective catalytic activity of the electrodes towards fuel and oxidant in a gas mixture, leading to the generation of an electromotive force. Because of its unique principle and structure, SC-SOFC has many advantages such as sealing-free, easy stacking, quick start-up and no carbon deposition, thus, it possesses large potential in application. Herein, the principles and characteristics of SC-SOFC are introduced. Furthermore, the SC-SOFC materials, micro-stack design, degeneration mechanisms and potential applications in recent years are reviewed systematically. In order to improve the output voltage and power of SC-SOFC micro-stack, the structure of micro-stack running in pre-mixed gas environment is modified, and the output power of four-cell micro-stack with star-type is increased to 420 mW. Then, the gas supply mode of SC-SOFC micro-stack is also improved step by step combined with the numerical simulation of computational fluid dynamics, and a single-channel/multi-point gas supply mode and a double-channel/multi-point gas supply mode are proposed. The output power of a single SC-SOFC micro-stack module is as high as 8.178 W. In addition, either external series or parallel connection of the micro-stack module, and the experimental verification with the burners are carried out. The results show that SC-SOFC can be easily connected into micro-stack module which produce several watts of output power, and are expected to be used in the combined heat-power system with heat supply prior in the future. By means of the simultaneous measurements of in situ resistance and open circuit voltage, it is also clarified that the repeated oxidation-reduction cycle of Ni at CH4-O2 atmosphere is the primary mechanism for the irreversible decay in SC-SOFC. This discovery later has promoted a new technology for the preparation of porous metals by oxidation-reduction method.国家自然科学基金项目(No.51872067);国家自然科学基金项目(No.21773048);国家自然科学基金项目(No.51602213)通讯作者:吕喆E-mail:[email protected]:LüZheE-mail:[email protected]. 哈尔滨工业大学物理学院,黑龙江 哈尔滨 1500012. 太原理工大学物理与光电工程学院,山西 太原 0300241. School of Physics, Harbin Institute of Technology, Harbin 150001, Heilongjiang, China2. College of Physics and Optoelectronics, Taiyuan University of Technology, Taiyuan 030024, Shanxi, Chin
Degradation Mechanism of LiNi0.83Co0.12Mn0.05O2 Cycled at 45 oC
No full text本文研究了高镍NCM811材料LiNi0.83Co0.12Mn0.05O2高温45 °C循环失效机理. 通过电化学交流阻抗谱（EIS）技术分析发现45 °C循环失效前后SEI膜阻抗（RSEI）和电荷转移阻抗（Rct）增长率最快,分别达到83.43%和211.34%. 采用XPS、TEM及FFT转换、XRD、XANES等手段分别分析了RSEI和Rct增长的主要影响因素. 其中,RSEI增长因素主要包括部分有机SEI膜组分转化成碳酸锂等无机成分,同时反应生成的LiF富集在活性物质周围,SEI膜厚度增长,阻抗升高. Rct增长因素主要包括晶体结构被破坏,层状晶相结构向尖晶石和岩盐相的转化,材料开裂,使电荷转移阻抗增加. 此外,对固相传质阻抗（Rw）影响因素也进行了分析,主要包括锂镍混排加剧,过渡金属元素溶出导致锂离子固相传质阻抗上升.Nickel-rich layered material has been considered as the most promising one for lithium ion batteries due to its high specific capacity. To further improve the lifetime performance, it is significant to investigate the degradation mechanisms deeply. In this study, the degradation mechanism of NCM811 (LiNi0.83Co0.12Mn0.05O2) being cycled at 45oC was systematically researched. Electrochemical impedance spectrum (EIS) results showed that the SEI resistance (RSEI) and charge transfer resistance (Rct) went up to 83.41% and 211.34% before and after the NCM811 material being cycled at 45oC, respectively. The main factors that influenced the RSEI and Rct were analyzed by means of XPS, TEM, XRD and XANES. The increase of RSEI was mainly ascribed to the conversion of some organic components to inorganic components such as lithium carbonate. Besides, the thickness of SEI film increased due to the side product of lithium fluoride (LiF) accumulated around the active materials. The increase of Rct was ascribed to the destruction of crystal structure, the phase transformations from R-3m to Fd-3m and to Fm-3m, and the micro-cracks appeared inside of the active particles. In addition, the solid mass transfer resistance (Rw) was found to become larger, which was mainly affected by the enhanced Li/Ni mixing and dissolutions of transition metal elements.通讯作者:马洪运E-mail:[email protected]:MAHong-yunE-mail:[email protected]天津力神电池股份有限公司,天津 300384Tianjin Lishen Battery Joint-Stock Co., Ltd. Tianjin 300384, Chin
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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