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Progressing in Differences:Msrx's and Engels's Early Thoughts:A Comparative Study of the Outlines of a Critique of National Economy and the Economic and philosophic Manuscripts of 1844
No full text黄学胜，中山大学马克思主义学院副教授、博士生导师，哲学博士。【中文摘要】在马克思恩格斯对立或差异论的语境下,有关马克思恩格斯青年时期的学术思想关 系研究体现为观点不一甚至相互对立,没有合理阐明并评价二者的真实关系。秉持思想史研究态 度,借助细致的文本比较可以发现,恩格斯在政治经济学批判方面领先于马克思，促进并推动了后 者的政治经济学批判工作;马克思则在哲学高度优于恩格斯，应当在哲学逻辑和经济学批判逻辑 相互作用的视域中来理解其政治经济学批判工作及与恩格斯的关系。马克思和恩格斯是在差异 中共同创立了历史唯物主义，抬高或贬低任何一方都是错误的。
【Abstract】The academic thoughts of Marx and Engels in their youth still need to be further researched. In the existing research carried out in the context of Marx and Engels's antagonism or difference theory，there are different viewpoints， some of which are even mutually contradictory，without reasonably clarifying and evaluating the true relationship between the two thinkers. In line with the research attitude of ideological history，and through detailed textual comparison，we can find that Engels is ahead of Marx in the criticism of political economy and advances the latter's political economic criticism ，whereas Marx is superior to Engels in philosophy. In order to understand his critique of political economy and his relationship with Engels，we should start from the perspective of the interaction between philosophical logic and economic crit¬ical logic. The two thinkers jointly founded historical materialism，and it is wrong to elevate one and downplay the value of the other.国家社会科学基金一般项目“马克思对现代性道德的批判及其意义研究”（19BZX008
Trapped by “Images”: A Critique of Image Communication from the Perspective of Political Economy
No full text陈世华，南昌大学新闻与传播学院教授、博士生导师，新闻学博士。【中文摘要】从国家形象、企业形象到个人形象,形象传播崛起的背后蕴含了深刻的政治经济文化 动因。形象传播以视觉转型趋势为思想根基，是政治权力的抗争形式，是形象商业价值的交易和 变现，契合社会文化心理，是数字图像技术驱动下的产物。形象传播的泛滥导致形象的拜物和异 化,让人身陷形象的困局，助长图像的暴政。形象传播的出路在于与形象保持距离,理性看待形 象,反抗形象的霸权，把握形象与内涵的和谐共存，回归真善美的形象传播伦理,建构批判性形象 传播学，践行视觉行动主义，回归形象传播正轨。
【Abstract】From national images，corporate images to personal images，the rise of image communication contains profound political，economic and cultural motivation. Based on the trend of visual transformation， image communication is a form of struggle for political power and is the transaction and realization of the commercial value of image，fitting with the social and cultural mentality. Moreover，it is a product under the driving force of digital image technology. The spread of images leads to fetishism and alienation of images，trapping people in the dilemma of images while promoting the tyranny of images. The way out of image communication lies in keeping a distance from the image，rationally looking at the image，resisting image hegemony，undering the harmonious coexistence of images and connotations，reverting to the image communication ethics of truth，goodness and beauty，constructing critical image communication，practicing visual activism，and returning to the right trajectory of image communication.国家社会科学基金后期资助项目“流行文化的政治经济学研究”（20FXWB033
Research Progresses in Polymeric Proton Exchange Membranes for Fuel Cells
No full text质子交换膜（PEM）是质子交换膜燃料电池的核心组件之一，具有隔绝阴阳极、提供质子传递通道和阻止燃料渗透的作用. 商业化应用的全氟磺酸PEM存在燃料渗透严重、高温条件下导电性差和成本高的问题，开发性能优良的聚合物PEM显得很有必要. 本文讨论了近年来聚合物PEM的研究进展，分别从聚合物的主链、支链和交联结构角度介绍了分子结构对薄膜相分离、质子导电性、稳定性和电池性能等性能的影响，并讨论了聚合物分子结构设计方面存在的问题，最后对燃料电池用聚合物PEM在未来的发展方向进行了展望.Proton exchange membrane (PEM) is one of the key components in PEM fuel cells, which possesses the function of separating the cathode and anode, affording proton transport channels and preventing fuel permeability. The property of PEM significantly influences the performance and service life of fuel cells. Nowadays, the commercially used Nafion membranes have the shortcomings of serious fuel permeability, low proton conductivity at elevated temperature and high price, which limits the rapid development of PEM fuel cells. Therefore, it seems to be urgent to develop novel PEMs with low cost and good comprehensive properties. Polymeric proton exchange membrane is an important developing direction in the research field of PEMs. This review focuses on the recent progresses in polymeric proton exchange membrane from the perspective of molecular structure. The effects of main backbones, side chains and crosslinking networks on the membrane properties, such as phase separation, proton conductivity, stability and cell performance, are analyzed. The existing problems in molecular structure design of polymeric PEMs are also discussed. Finally, an outlook for future developing directions in polymeric proton exchange membrane applied in fuel cells is presented. By comparing the effect of different structures of polymeric PEMs on their properties, it is concluded that the property of polymeric PEMs can be improved by the following three strategies: (1) Preparing block copolymer or locally and densely sulfonated polymers. The method is beneficial for obtaining high proton conductivity by adjusting the structure of main backbones. (2) Grafting functional hydrophilic or hydrophobic side chains. By using the high mobility of side chains, obvious phase separation of PEMs can be obtained as well as high proton conductivity. Polymers containing hydrophobic side chains are widely utilized as anion exchange membranes, however, the studies in polymers containing hydrophobic side chains as PEMs are still few up to now. (3) Preparing fully crosslinking PEMs. The formed crosslinking networks guarantee high chemical and dimensional stabilities of PEMs, which is profitable for the long-time running of PEM fuel cells. The work aims to provide available guidance for the synthesis of novel polymeric PEMs and promote their practical applications.国家自然科学基金项目(Nos. 21603197, 21233006, 21473164)、湖北省自然科学基金青年基金项目(No.2016CFB181)，中央高校基本科研业务费专项(No. CUGL180403)及中国地质大学（武汉）先进能源技术与应用基地资助作者联系地址：1. 中国地质大学（武汉）材料与化学学院，可持续能源实验室，湖北 武汉 430074；2. 华中科技大学化学与化工学院，能量转换与存储材料化学教育部重点实验室，材料化学与服役失效湖北省重点实验室，湖北 武汉430074Author's Address: 1. Sustainable Energy Laboratory, Faculty of Materials Science and Chemistry, China University of Geosciences Wuhan, Wuhan 430074, China; 2. Key Laboratory of Material Chemistry for Energy Conversion and Storage Huazhong University of Science and Technology, Ministry of Education, Hubei Key Laboratory of Material Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China通讯作者E-mail：[email protected]；[email protected]
Living Environment,Social Status and Health of the Elderly
No full text徐延辉,厦门大学社会与人类学院教授、博士生导师，经济学博士；刘彦，厦门大学社会与人类学院社会学系博士研究生。【中文摘要】由于身体机能和自我恢复功能下降，老年人成为健康问题的高危群体。从居住环境和社会地位入手探究老年人健康状况的影响机制可以发现,老年人的居住环境资源和主观社会地位均会显著作用于其健康水平。老年人的健康水平不仅呈现明显的地位化特征，而且还与外在的环境资源联系紧密，研究结果在一定程度上支持了健康不平等的“物质主义模型”因此,政府在制定与老年人健康有关的政策时，应将老年人居住环境所包含的物质资源和情感资源考虑在内，充分发挥居住环境资源在提升老年人健康中的作用。
【Abstract】As their physical and self-recovery functions decline，the elderly become a high-risk group with health problems. This paper explores the mechanism of health among the elderly from the perspective of the living environment. This study finds that the living environmental resources and subjective social status of the elderly significantly influence their health. In addition to the direct effect，living environmental resources can also afect the elderly s health through subjective social status which plays a partial intermediary role. Our research results indicate that the health status among the elderly not only possesses obvious status characteristics，but is also closely linked to external environmental resources. The results support the “materialist explanatory model” of health inequality to a certain extent. The policy implications of our findings are as follows ：when formulating policies related to the health of the elderly，the government should take into account the material resources and emotional resources in the living environment，and give full play to the effect of living environmental resources in improving the health status among the aging population
Digital-WGS: Automated, highly efficient whole-genome sequencing of single cells by digital microfluidics
Get PDF单细胞全基因组测序(whole-genome sequencing, WGS)是表征细胞内DNA动态变化的关键手段，可为我们提供全面、深度的生物学信息，是生命科学领域研究的热点。然而，单细胞全基因组测序仍面临着诸如样品制备复杂、成本高、扩增偏置性强、误差大的挑战。杨朝勇教授课题组搭建了基于数字微流控的单细胞操控与纳升级全基因组测序平台Digital-WGS，可用于一体化、全自动的单细胞处理与分析。通过Digital-WGS方法制备的单细胞样本在不同测序深度下均展示出了高均一性、高覆盖率、高准确性的优势，解决了当前单细胞基因组测序操作复杂、成本高、均一性差、准确度低等问题，为单细胞基因组测序的广泛应用提供了新的思路。
本研究工作在化学化工学院杨朝勇教授的指导下完成，2015级iChEM直博生阮庆宇为第一作者。Single-cell whole-genome sequencing (WGS) is critical for characterizing dynamic intercellular changes in DNA. Current sample preparation technologies for single-cell WGS are complex, expensive, and suffer from high amplification bias and errors. Here, we describe Digital-WGS, a sample preparation platform that streamlines high-performance single-cell WGS with automatic processing based on digital microfluidics. Using the method, we provide high single-cell capture efficiency for any amount and types of cells by a wetted hydrodynamic structure. The digital control of droplets in a closed hydrophobic interface enables the complete removal of exogenous DNA, sufficient cell lysis, and lossless amplicon recovery, achieving the low coefficient of variation and high coverage at multiple scales. The single-cell genomic variations profiling performs the excellent detection of copy number variants with the smallest bin of 150 kb and single-nucleotide variants with allele dropout rate of 5.2%, holding great promise for broader applications of single-cell genomics.We thank the National Natural Science Foundation of China (21927806, 21735004, 21521004, and 21325522), the National Key R&D Program of China (2018YFC1602900, 2019YFA0905800), Innovative Research Team of High-Level Local Universities in Shanghai (SSMU-ZLCX20180701), and the Program for Changjiang Scholars and Innovative Research Team in University (IRT13036) for financial support. 研究工作得到了国家自然科学基金(21927806、21735004、21521004、21325522), 国家重点研发项目(2018YFC1602900、2019YFA0905800)和教育部“长江学者和创新团队发展计划” (IRT13036)的资助与支持
Preparation and Characterization of Cathode Supported Solid Oxide Fuel Cell
No full text采用固相反应法合成A缺位的(La0.8Sr0.2)0.95MnO3(LSM95)作为阴极材料,Zr0.9Sc0.1SO1.95(SSZ)商业粉体作为电解质材料,溶胶-凝胶法合成的La0.8Sr0.2Cr0.5Mn0.5O3-(LSCrM)作为阳极电催化材料,利用流延、共烧结及浸渍法得到结构为LSCrM-CeO2|SSZ|3YSZ-LSM95的阴极支撑型固体氧化物燃料电池,分别在氢气气氛和甲烷气氛中进行电化学性能测试. 结果表明,浸渍0.11 g·cm -2 CeO2的LSCrM-CeO2|SSZ|3YSZ-LSM95单电池在以CH4为燃料时,600、650、700、750和800 oC下的功率密度分别为1.68、4.70、12.40、28.08和54.78 mW·cm -2,表现出一定的电化学性能和较好的稳定性.A site deficient (La0.8Sr0.2)0.95MnO3 (LSM95) powder was synthesized by solid state reaction as a cathode material. The commercial Zr0.9Sc0.1SO1.95 (SSZ) was selected as an electrolyte material and La0.8Sr0.2Cr0.5Mn0.5O3- (LSCrM) was synthesized by sol-gel method as an anode material. Accordingly, single cells of LSCrM-CeO2|SSZ|3YSZ-LSM95 were prepared by tape casting, sintering and impregnation. The single cell test results for LSCrM-CeO2|SSZ|3YSZ-LSM95 with 0.11 g·cm -2 CeO2 and using CH4 as a fuel showed the power densities of 1.68, 4.70, 12.4, 28.08 and 54.78 mW·cm -2 at 600, 650, 700, 750 and 800 oC, respectively. Durability test at the current density of 46.50 mA·cm -2 for over 130 h revealed that the cell degradation was owing to the decrease of open circuit voltage. The impregnated anode had good stability in performance. No carbon deposition was observed on the anode after the cell operation with CH4. The as-synthesized LSM95 powder exhibited good chemical compatibility with zirconia electrolyte, making it possible to prepare cathode supported cells with co-sintering. Meanwhile, LSCrM could form the perovskite phase at 900 oC and obtain the similar thermal expansion coefficient to the cathode support and electrolyte, which is contributed to the stability of multi-layer structure in the cell. The successful preparation of the cathode supported cells with a simple method shall provide a good platform for the research of various new anode materials. With further optimization in the porosity of cathode support and introduction of more active cathode functional layer, the cell performance will be enhanced.国家自然科学基金项目(No.51836004);徐州市项目(KH17004)通讯作者:王绍荣E-mail:[email protected]:WANGShao-rongE-mail:[email protected]中国矿业大学化工学院,江苏 徐州 221116School of Chemical Engineering and Technology, China University of Mining and Technology,Jiangsu 221116, Xuzhou, Chin
Synthesis and Raman Study of Hollow Core-Shell Ni1.2Co0.8P@N-C as an Anode Material for Sodium-Ion Batteries
No full text本文设计制备了一种新型的氮掺杂碳包覆镍钴双金属磷化物中空核壳结构纳米立方体(Ni1.2Co0.8P@N-C)作为钠离子电池负极材料. 该材料以镍钴类普鲁士蓝(PBA)纳米粒子为模板,先后经水热法、磷化法和高温碳化处理后合成. 将其作为活性材料应用在钠离子电池中,该材料展现出优异的循环稳定性,当以100 mA·g-1的电流密度循环至200圈时,该材料的库仑效率保持在99.3%. 进一步通过对不同电位下Ni1.2Co0.8P@N-C材料中的氮掺杂碳进行原位拉曼光谱测试,结果显示钠离子在氮掺杂的碳壳中的脱嵌行为具有较大程度的可逆性,研究结果对钠离子电池充放电过程的后续电化学研究提供了有价值的信息.With the increasing demand for large-scale energy storage, great progress has been made in discovering new advanced energy storage materials. Sodium-ion batteries (SIBs) have attracted much attention in recent years due to their use of abundant sodium resources and their comparable electrochemical capacity to lithium-ion batteries (LIBs). In this paper, we developed novel hollow core-shell Ni-Co bimetallic phosphide nanocubes with N-doped carbon coatings (Ni1.2Co0.8P@N-C) as the anode material for SIBs. The material was synthesized through a low-temperature phosphorization method using resorcinol formaldehyde (RF) resin coating with a Ni-Co Prussian blue analogue (PBA) as a template and a subsequent thermal annealing process. The size of the as-obtained nanocubes was about 310 nm with a 19 nm N-doped carbon shell. When used as the anode material of SIBs, Ni1.2Co0.8P@N-C exhibited the excellent electrochemical cycling stability and demonstrated an especially high coulombic efficiency of 99.3%, even after 200 cycles with current density of 100 mA·g-1. Furthermore, in-situ Raman spectroscopy was used to investigate the electrode material in order to understand the electrochemical processes in the N-doped carbon shell of Ni1.2Co0.8P@N-C. The results showed that the intercalation and de-intercalation behavior of sodium ions in the N-doped carbon shell was almost reversible, providing valuable information about the charge and discharge processes in SIBs for the follow-up electrochemical studies.国家自然科学基金项目(No.21775127)、福建省自然科学基金项目(No.2018J05025)、厦门市科技局产学研协同创新及合作项目(No.3502Z20173017)资助通讯作者:许清池,李剑锋E-mail:[email protected];[email protected]:XUQing-chi,LIJian-fengE-mail:[email protected];[email protected]. 厦门大学物理科学与技术学院,福建 厦门 3610052. 厦门大学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 3610051. College of Physical Science and Technology, Xiamen University, Xiamen 361005, Fujian, China2. State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, Chin
Stability Studies for a Membrane Electrode Assembly Type CO2 Electro-Reduction Electrolytic Cell
No full text电化学还原CO2可实现CO2的资源化转化,是缓解因其过度排放所导致诸多环境问题的关键技术. 本文提出了一种膜电极（membrane electrode assembly,MEA）构型CO2还原电解单池的结构设计,可同步实现气体扩散阴极两侧CO2的供给与电解质液层的更新. 基于该MEA构型电解池,实验考察了电解质液层中KHCO3浓度和更新与否对氮掺杂石墨烯锚定的Ni电极表面CO2电还原制备CO的反应活性、产物分布与稳定性的影响. 结果表明,若电流密度低于5 mA·cm-2,KHCO3浓度显著影响电解电势而非产物分布. CO2还原电解单池在稳定运行中存在着“可逆”与“不可逆”两种衰减模式. 其中,阴极/电解质界面处催化剂的流失是 “不可逆”衰减形成的原因;而电解质液层中KHCO3溶液的流失导致了MEA构型CO2还原单池的“可逆”衰减,周期性更新KHCO3电解质是降低其“可逆”衰减的有效方法.Electro-catalytic reduction is an efficient way to achieve resourcable transformation of CO2, which is one of the important techniques to solve the global environmental problems originated from excessive CO2 emission. In this study, a membrane electrode assembly(MEA) type CO2 electro-reduction electrolytic cell was constucted, which enables CO2 feeding and real-time KHCO3 aqueous updating on both sides of the cathode gas diffusion electrode (GDE). By means of the electrolytic cell, effects of KHCO3 concentration and updating inside the liquid electrolytic chamber on CO2 electro-reduction activity, production distribution and stability were investigated. The experimental results suggested that the KHCO3 concentration exerted strong influence on the cell voltage rather than the production distribution for the current densities lower than 5 mA·cm-2. The performance of MEA type CO2 electro-reduction cell decayed in both “reversible” and “irreversible” ways. Catalysts leaking at the GDE/liquid electrolyte interface might be respossible for the cell “irreversible” decay. Meanwhile, th leakage of KHCO3 aqueous electrolyte arose from gas accumulation in the liquid electrolytic chamber contributed to the “reversible” degradation, which could be recovered effectively by updating the KHCO3 aqueous electrolyte.辽宁省自然科学基金项目（No.201602162）、大连理工大学GF创新基金项目（No.DUT18GF308）和国家电网公司科技项目（No.SGRI-DL-71-16-015）资助通讯作者:毛庆,黄延强E-mail:[email protected];[email protected]:MAOQing,HUANGYan-qiangE-mail:[email protected];[email protected]. 大连理工大学化工学院,辽宁 大连 116023
2. 中国科学院大连化学物理研究所,航天催化与新材料研究室,辽宁 大连 116023
3. 全球能源互联网研究院,北京 1022001. School of Chemical Engineer, Dalian University of Technology, Dalian 116024, China2. Laboratory of Aerospace Catalysts and New Materials, Dalian Institute of Chemical Physics, Chinese Academy of Science, Dalian 116023, China3. Global Energy Interconnection Research Institute, Beijing 102200, Chin
Preparations of Nano-MnOx/Ti Electrocatalytic Membrane Electrode for Catalytic Oxidation of Cyclohexane Using Intermittent Electrodeposition
No full text高选择性氧化环己烷（CHA）制备环己酮和环己醇（KA油）具有重要的工业价值和应用前景. 本文提出采用间歇电沉积法制备纳米MnOx催化剂负载多孔管式钛膜,构建电催化膜反应器（ECMR）催化氧化环己烷制备环己醇和环己酮. 利用场发射扫描电子显微镜（FESEM）、X射线衍射仪（XRD）和电化学工作站等表征手段对催化剂的结构与性能进行表征. 结果表明,间歇电沉积法制备的催化剂为纳米花球状γ-MnO2. 与基体钛膜相比,MnOx/Ti膜电极具有更优的电化学性能和传质性能. 此外,以MnOx/Ti电催化膜为阳极,不锈钢网为阴极构建ECMR. 当环己烷初始浓度30 mmol·L-1、反应温度30oC、停留时间34.3 min、电流密度2.3 mA·cm-2等条件下,ECMR环己烷转化率达25.6%,KA油总选择性高于99%. 同时,ECMR重复使用8次后表现较高催化稳定性.Cyclohexanone and cyclohexanol (KA oil) obtained from highly selective oxidation of cyclohexane (CHA) show important industrial value and application prospects. In this work, the intermittent electrodeposition was developed to prepare nano-MnOx catalyst loading porous tubular titanium membrane electrode (MnOx/Ti), which was employed to constitute an electro-catalytic membrane reactor (ECMR) for the oxidation of cyclohexane to produce cyclohexanol and cyclohexanone. The surface morphology, crystal structure and electrochemical property of the catalysts were characterized by FESEM, XRD and electrochemical workstation, respectively. The results show that the catalyst prepared by the intermittent electrodeposition displayed nano-flower-like γ-MnO2. Compared with titanium membrane, the MnOx/Ti electrocatalytic membrane exhibited better electrochemical performance and mass transfer performance. Furthermore, the ECMR was constructed by using the MnOx/Ti electrocatalytic membrane as the anode and the stainless steel mesh as the cathode. When the initial concentration of cyclohexane was 30 mmol·L-1, the reaction temperature was 30oC, the residence time was 34.3 min and the current density was 2.3 mA·cm-2. The cyclohexane conversion rate reached 25.6% and the total selectivity of KA oil exceeded 99%. Simultaneously, the ECMR with MnOx/Ti electrode showed a good stability during the oxidation of cyclohexane.国家自然科学基金（No.21676200，No.21576208）、教育部创新团队发展计划（No.IRT-17R80）和天津科学支撑计划（No.17JCYBJC19800）通讯作者:李建新E-mail:[email protected]:LIJian-xinE-mail:[email protected]. 天津工业大学材料科学与工程学院,分离膜与膜过程国家重点实验室,天津 3003872. 天津工业大学化学与化工学院,天津 3003873. 南开大学先进能源材料化学教育部重点实验室,天津 3000711. State Key Laboratory of Separation Membranes and Membrane Processes, School of Materials Science and Engineering, Tianjin Polytechnic University, Tianjin 300387, P. R. China2. Chemistry and Chemical Engineering, Tianjin Polytechnic University, Tianjin 300387, P. R. China3. Key Laboratory of Advanced Energy Materials Chemistry, Ministry of Education, Nankai University, Tianjin 300071, P. R. Chin
