Significant promotional effect of CCl4 on fullerene yield in the graphite arc-discharge reaction

地址: 1. Xiamen Univ, Dept Chem, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 电子邮件地址: [email protected] of a small quantity ( similar to 3%) of CCl4 to the He atmosphere of the graphite arc-discharge reaction revealed a marked increase in fullerene yield

Promoting electrocatalytic CO2 reduction to formate via sulfur-boosting water activation on indium surfaces

一般认为，H2O还原析氢反应是CO2还原反应的竞争反应，若促进H2O活化将降低CO2还原反应的法拉第效率。因此，基于该认识设计出的高CO2还原法拉第效率的催化剂常常活性低。王野课题组打破这种认识，提出H2O分子活化在CO2还原中起着重要的作用，成功合成出硫修饰In催化剂来活化H2O分子而促进CO2还原制甲酸的新方法，该催化剂在非常宽的电流密度范围内（25~100 mA cm-2），均可以维持85%以上的甲酸法拉第效率。将硫拓展至硒和碲等其它硫族元素以及将金属铟拓展至铋和锡等其它p区金属，均实现很好的促进效果，表明通过促进水的活化来提高CO2电催化还原性能具有普适性。该工作为理性设计高效的CO2还原电催化剂提供了新策略。 该研究工作实验部分主要由王野、张庆红教授指导，能源材料化学协同创新中心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；理论计算部分由吴德印教授指导，2015级博士生张霞光（共同第一作者）完成。醇醚酯国家工程实验室高级工程师康金灿参与了部分实验表征。上海光源姜政教授和孙凡飞博士为同步辐射表征提供了支持。【Abstract】Electrocatalytic reduction of CO2 to fuels and chemicals is one of the most attractive routes for CO2 utilization. Current catalysts suffer from low faradaic efficiency of a CO2-reduction product at high current density (or reaction rate). Here, we report that a sulfur-doped indium catalyst exhibits high faradaic efficiency of formate (>85%) in a broad range of current density (25–100 mA cm−2) for electrocatalytic CO2 reduction in aqueous media. The formation rate of formate reaches 1449 μmol h−1 cm−2 with 93% faradaic efficiency, the highest value reported to date. Our studies suggest that sulfur accelerates CO2 reduction by a unique mechanism. Sulfur enhances the activation of water, forming hydrogen species that can readily react with CO2 to produce formate. The promoting effect of chalcogen modifiers can be extended to other metal catalysts. This work offers a simple and useful strategy for designing both active and selective electrocatalysts for CO2This 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, and 21503176). We thank staff 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）等项目的资助

Electrocatalytic reduction of CO2 to ethylene and ethanol through hydrogen-assisted C-C coupling over fluorine-modified copper

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

The graphite arc-discharge in the presence of CCl4: Chlorinated carbon clusters in relation with fullerenes formation

通讯作者地址: Xie, SY (通讯作者), Xiamen Univ, Dept Chem, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 地址: 1. Xiamen Univ, Dept Chem, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 2. Wuhan Univ, Dept Chem, Wuhan 430072, Peoples R ChinaThe graphite arc-discharge in the atmosphere consisting of CCl4 40 Torr and increasing partial pressure of He from 0 to 300 Torr produced, in addition to carbon species such as graphite and fullerenes C60 and C70, numerous chlorinated carbon clusters (CCCs). The yields of some CCCs, including C6Cl6 (perchlorobenzene), C10Cl8 (perchloronaphthalene), C12Cl8 (perchloroacenaphthylene) and C12Cl8 (isomer II), C14Cl8 (isomer I), C16Cl10 (perchlorofluoranthene), C18Cl10 (isomer I and II), and C20Cl10 (isomer I), correspond well with C60 yields, which may imply these CCCs share the same growth mechanism with fullerenes. Such a yield correlation can be used to distinguish the fullerene precursors from the irrelevant by-products, thus contributes to the mechanistic study of fullerene formation

Capturing the labile fullerene[50] as C50Cl10

地址: 1. Xiamen Univ, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 2. Xiamen Univ, Dept Chem, Xiamen 361005, Peoples R China 3. Chinese Acad Sci, Inst Chem, Beijing 100080, Peoples R China 4. Chinese Acad Sci, Wuhan Inst Phys & Math, State Key Lab Magnet Resonance & Mol Phys, Wuhan 430071, Peoples R China 电子邮件地址: [email protected]

Risk Attitude in Local Culture and Corporate Risk-Taking

【中文摘要】风险文化作为重要的文化维度，深刻地影响公司治理。本文以2008～2014 年沪深 A 股非金融上市公司为研究对象，从地区正式制度、企业制度和管理者风险偏好的角度，考察地区风险文化对企业风险承担的影响。结果发现：在其他条件相同时，地区风险文化通过优化地区金融生态、推进对管理层采用股权激励薪酬制度及提高管理层的风险容忍度，促进企业风险承担。进 一步研究发现，当企业外部经济政策不确定性较高、陷入财务困境及管理层自主权较大时，地区风险文化促进企业风险承担的效应较显著。此外，本文还发现地区风险文化更多地体现为冒险精神，通过促进企业风险承担，进而优化企业资源配置效率。本文的研究丰富了文化与金融理论的文献，拓展了风险承担影响因素的研究，有利于深化对正式制度与非正式制度相互作用的理解。 【Abstract】As an important cultural dimension，risk attitude in local culture has a profound impact on how managers manage their businesses. In this paper，we use a sample of all A-share listed companies from 2008 to 2014 to study the influence of risk attitude in local culture on corporate risk-taking by combining local formal institution，enterprise chapters，and managerial risk attitude. Our results show that risk attitude in local culture promotes corporate risk-taking through optimization of local financial ecology，adoption of equity-based incentives and promotion of managerial risk tolerance. Further analysis shows that risk attitude in local culture has a larger effect on corporate risk-taking when the size of the company is small，when management has greater autonomy，when the uncertainty of external environment is high，or when the company is in financial difficulties. Lastly，we find that risk attitude in local culture helps to allocate resources more efficiently through promoting corporate risk-taking. This paper enriches the literature on the relation between culture and finance，extends the influencing factors of risk-taking，and deepens understanding of the interaction between formal and informal institutions.本文受到国家自然科学基金青年科学基金项目“公益型积极股东能否发挥治理作用？——基于中证投服‘持股行权’的理论与实证研究”（ 71902149）；教育部人文社会科学研究规划基金项目“去杠杆影响企业风险承担的经济后果、机制路径及优化策略研究”（ 19YJA630093）；教育部人文社会科学研究青年基金项目“上市公司市值管理行为异化现象的诱因与监管对策研究”（ 19YJC630096）的资助

Reverse Mergers and Corporate Innovation:A Comparative Analysis Based on Reverse Mergers and IPO Companies

佟岩，北京理工大学管理与经济学院教授、博士生导师，管理学博士；谢思敏，北京理工大学管理与经济学院信息披露与公司治理研究中心研究助理；韩春阳，北京理工大学管理与经济学院信息披露与公司治理研究中心研究助理；李思飞，北京外国语大学国际商学院 副教授,经济学博士。【中文摘要】创新是推进企业发展的催化剂。创新活动需要资金和技木，而上市可以为企业提供一个融资平台,进而能够为企业创新水平的提升提供资金保障。我国企业上市一般通过首次公开募股和反向收购两种途径。相较于IPO上市,反向收购具有上市便捷、成本低等优势,但同时可能由于约束较少，存在ー些潜在问题。以2007—2015年A股反向收购与IPO上市的公司为样本,可分析这两类公司上市后在企业创新水平上的差异,研究发现:(1)与IPO公司相比,反向收购公司上市后的创新产出更低；(2)如果通过反向收购上市的公司为国有公司,可以缓解对创新的抑制作用；(3)当董事长与总经理两职合一时，则会加剧反向收购对创新的负面影响。 【Abstract】Innovation is significant for promoting the development of enterprises. More and more companies are paying attention to improving their own innovation capabilities and increasing R&D investment. R&D activities require capital and technology，while going public can provide companies with a good platform，which can provide funds for corporate R&D activities.Chinese enterprises are generally listed through IPOs and reverse mergers. Compared with IPOs，reverse mergers are favored by an increasing number of unlisted companies for their advantages，such as convenient process and low cost. Based on an empirical analysis of Chinese listed companies from 2007 to 2015，the impacts of reverse mergers and IPOs on corporate innovation are compared，and the conclusions are ：(1)compared with IPO companies，the level of innovation of reverse - requisition companies after listing is lower; (2) if the companies listed through reverse mergers are state - owned companies，their level of innovation is higher；and (3) CEO duality negatively affects the relationship between reverse merger companies and the level of innovation.国家自然科学基金面上项目“创新驱动型并购的影响因素与经济后果研究”（71672007);国家自然科学基金面上项目“反向收购整体上市的动机、路径与经济后果研究”（71372015

Effects of Rotating Magnetic Fields on PEM Fuel Cell Performance

外加磁场可以提高PEM（Proton Exchange Membrane，质子交换膜）燃料电池的工作性能，本文通过在PEM燃料电池表面分别附加正方形梯度磁场、同极性组合圆柱形磁场以及异极性组合圆柱形磁场，分析旋转磁场、静态磁场以及未加磁场3种磁场环境下燃料电池的输出功率密度变化. 研究发现，外部磁场的分布规律不同，磁场的变动对燃料电池的影响也不相同，尤其是异极性组合磁场，旋转的磁场使燃料电池的最大功率密度提高了21.27%，明显高于加载静态磁场时提高的11.70%. 旋转磁场产生的效果与磁场旋转速度有关，提高转速有利于增强磁场对燃料电池工作性能的影响，当转速为30 r·min-1时影响最大，随着转速进一步提高，影响效果逐渐变差。Proton Exchange Membrane (PEM) fuel cell performance may be improved by application of additional magnetic fields. In this work, one square permanent magnet, made of either 16 combination cylinder magnets with homopolarity or 16 combination cylinder magnets with heteropolarity, was exerted on the fuel cell surface to produce additional magnetic field affecting PEM fuel cell performance. The influences of magnetic field status (rotating, static and none) on polarization and power density curves measured in a PEM fuel cell were investigated. The results verified the benefit of magnetic field, proving that the magnetic field distribution could improve the fuel cell output. Especially, the rotating combination magnet with heteropolarity enlarged the power density by 21.27%, which has advantage to the static magnetic field of 11.70% enhancement. Finally, the rotating speed was related to the fuel cell output power. High rotating speed was beneficial to the performance improvement, and the maximum power density was obtained at 30 r·min-1. However, the performance became worse upon further acceleration.作者联系地址：上海电力学院 能源与机械工程学院，上海，200090Author's Address: College of Energy and Mechanical Engineering, Shanghai University of Electric Power, Shanghai, 200090通讯作者E-mail：wumaoliang@shiep. edu. c