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Progress of Lithium-Ion Transport Mechanism in Solid-State Electrolytes
No full text固态电解质在室温下表现出非凡的离子导电性,使其有潜力应用于全固态锂离子电池。开发新的高性能固态电解质需要对锂离子传输机理及其规律进行深入研究。本文论述了近期研究中锂离子传输机理方面的研究进展,包括离子传输理论基础的概述;总结Li10GeP2S12、Li7La3Zr2O12和Li1+xAlxTi2-x(PO4)3固态电解质材料中晶体结构、离子传输和研究进展;阐述锂离子传输中结构特征、传输机理（单离子跳跃传输和多离子协同传输）以及构效关系;总结（反）Meyer-Neldel规则的关键问题和相关电解质材料。最后,展望了给出电解质材料的设计策略和未来机理研究的重点,为无机固态电解质材料的探索提供新的思路和方向。Inorganic crystalline solid electrolytes exhibit exceptional room-temperature ionic conductivities, giving them the potential to enable all-solid-state lithium (Li) - ion batteries. Developing new high-performance electrolytes is one of the most critical challenges to realize solid-state batteries, which requires understanding how chemistry facilitates fast ionic conduction and what the Li-ion migration mechanism is in inorganic solid electrolytes. In this review, we aim to summarize recent fundamental research progress in Li-ion transport, including crystal structure, behavior of ion migration (i.e., single-ion jump and multi-ions cooperative migration), and the relationship between ion migration and microstructure. Generally, ion transport in crystalline structure can be categorized into vacancy and non-vacancy mechanism. For Li-ion conduction, the migration can be achieved through single-ion hopping and collective diffusion mechanism. For single-ion hopping mechanism, the diffusivity is determined by the depth of potential well (activation energy) and lattice dynamics; whereas in the later mechanism Li-ion moving from high potential to low potential could partially offset the energy required for Li-ion moving from low potential to high potential. By studying the collective diffusion from the perspective of local structures, it is believed that collective diffusion in fast ion conductor originates from the local “dual Li-S/O” structure units, which can be characterized by the “nearest Li-Li distance”. Next, the paradigm of ion transport in solids is summarized. It is pointed out that most ion conductors follow Meyer-Neldel rule, where the activation energy and pre-exponential factor are mutual compensating. As a result, a balance should be adapted between these two values to achieve high Li-ion conductivity. However, for some fast ion conductors, the relationship does not follow the Meyer-Neldel rule (i.e., anti-Meyer-Neldel rule). Therefore, the physical significance of anti-Meyer-Neldel rule should be understood to develop next-generation lithium ion conductors. In the end, future perspectives and open questions are proposed to design and develop high-performance inorganic solid electrolytes.国家材料基因组重点专项(2016YFB0700600);广东省创新团队(2013N080)通讯作者:潘锋E-mail:[email protected]:FengPanE-mail:[email protected].北京大学深圳研究生院新材料学院,广东 深圳 5180552.广东工业大学轻工化工学院,广东 广州 5100061. School of Advanced Materials, Shenzhen Graduate School, Peking University, Shenzhen 518055, Guangdong, China2. School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, Guangdong, Chin
DFT Study of Nim@Pt1Aun-m-1 (n=19, 38, 55, 79; m = 1, 6, 13, 19) Core-Shell ORR Catalyst
No full text燃料电池的阴极反应的反应动力学速率非常慢,限制了燃料电池技术的发展。因此,寻找低成本、高活性的氧还原催化剂具有重要的意义。多元金属核壳团簇表现出优良的氧还原活性。在本文中,以原子个数为19、38、55和79的八面体团簇作催化剂模型,采用密度泛函理论(GGA-PBE-PAW)方法,研究了一系列不同尺寸核壳Nim@Mn-m (n = 19, 38, 55, 79;m = 1, 6, 13, 19; M = Pt, Pd, Cu, Au, Ag)团簇催化剂的活性规律。优化*O、*OH和*OOH吸附中间体结构,计算了吸附自由能和反应吉布斯自由能,以超电势为催化活性的描述符,研究了单原子Pt嵌入Nim@Aun-m团簇的活性规律。结果表明,Ni6@Pt1Au31具有最好的ORR活性,并且Ni1@Pt1Au17、Ni6@Pt1Au31、Ni13@Pt1Au41、Ni19@Pt1Au5表现出比Pt38团簇以及Pt(111)表面更高的催化活性。Bader电荷和态密度分析表面,核壳之间的电荷转移以及单原子Pt嵌入Nim@Aun-m表面,改变了吸附位的电子性质,降低了*OH的吸附强度,提高了ORR活性。单原子Pt嵌入Nim@Aun-m表面可能是一种合适的多元金属核壳ORR催化剂设计策略。The slow kinetics of oxygen reduction reaction (ORR) limits the performance of low temperature fuel cells. Thus, it needs to design effective catalysts with low cost. Core-shell clusters (CSNCs) show promising activity because of their size-dependent geometric and electronic effects. The ORR activity trend of Nim@Pt1Aun-m-1(n = 19, 38, 55, 79; m = 1, 6, 13, 19) was studied using the GGA-PBE-PAW methods. The adsorption configurations of *O, *OH and *OOH were optimized and the reaction free energies of four proton electron (H+ + e-) transfer steps were calculated. Using overpotential as a descriptor for the catalytic activity, Ni6@Pt1Au31 was found to be the most active ORR catalyst. Ni1@Pt1Au17, Ni13@Pt1Au41, and Ni19@Pt1Au59 had better activity than pure Pt clusters and Pt(111). Bader charge and DOS data indicate that the single Pt atom embedded on Nim@Aun-m can tune the electronic property of active site, and thus, significantly improve the activity. The present study showed that the single Pt atom embedded on Nim@Aun-m is a rational strategy to design effective core-shell ORR catalysts.通讯作者:田东旭,燕希强E-mail:[email protected];[email protected]:Dong-XuTian,Xi-QiangYanE-mail:[email protected];[email protected].大连理工大学化工学院,精细化工国家重点实验室,辽宁 大连 1160242.佛山（云浮）氢能产业与新材料发展研究院,广东省氢能技术重点实验室,广东 佛山 5280001. State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, Liaoning, China2. Guangdong Key Laboratory for Hydrogen Energy Technologies, Foshan University, Foshan 528000, Guangdong, Chin
The Theoretical Genealogy of Administrative Law in China since the Reform and Opening-up
No full text刘连泰，厦门大学法学院教授、博士生导师，法学博士；孙悦，厦门大学法学院博士研究生。【中文摘要】:改革开放以来,中国行政法学分别呈现为宪法学谱系的行政法学、行政诉讼法学谱系的行政法学和以规制为中心谱系的行政法学。这三种谱系的起点大致清晰，延宕至今。2018年宪法修正案将习近平新时代中国特色社会主义思想载人宪法，明确中国共产党领导是中国特色社会主义最本质的特征,行政法学的理论谱系应当随之予以调适。新时代的行政法学理论谱系应以习近平法治思想为定泊之锚，遵从整体性的逻辑。宪法学谱系的行政法学、行政诉讼法学谱系的行政法学和以规制为中心谱系的行政法学经由视域融合，构建出以习近平法治思想为灵魂的谱系开放的当代中国行政法学。
【Abstract】Since the Reform and Opening - up， the genealogy of Chinese administrative law has manifested as three branches ： constitutional- centered administrative law，litigation - centered administrative law and regulation - centered administrative law，which has remained in place to this day.With its 2018 amendment，the Constitution incorporated Xi Jinping Thought on Socialism with Chinese Characteristics for a New Era，making it clear that the leadership of the Communist Party of China is the most essential feature of socialism with Chinese characteristics ；as such，the genealogy of administrative law should be adjusted accordingly. Anchored by Xi Jinping Thought on the Rule of Law，the theoretical genealogy of administrative law in the new era should follow the logic of integrity. Constitutional-centered administrative law，litigation-centered administrative law and regulation- centered administrative law are integrated to build the open genealogy of contemporary administrative law with Xi Jinping Thought on the Rule of Law as the soul.国家社会科学基金重大研究专项项目“社会主义核心价值观融入行业规章体系建设的法治路径研究”（20VHJ007
高血清流行人群新生儿先天性巨细胞病毒感染筛查策略对比：一项母婴队列研究
No full text巨细胞病毒（Cytomegalovirus，CMV）感染极为常见，感染人体后将造成终身潜伏带毒、机会性活跃，大多不引起明显的临床症状，但孕妇的CMV病毒活跃可能形成垂直传播而导致新生儿宫内先天感染，损伤胎盘并在胎儿神经细胞中复制。CMV是全球儿童感音神经性耳聋的最主要病因。及时筛查确诊新生儿CMV先天感染是改善患儿临床结局的关键。该研究团体通过多中心母婴队列观察，系统对比了基于新生儿唾液和尿液标本进行先天性巨细胞病毒感染筛查的多种策略，提出了初次筛查和再次确认检测的最优样本采集时间窗口和样本类型，对包括中国以及大多数发展中国家在内的广大巨细胞病毒感染高流行区的先天性巨细胞病毒感染防控工作具有重要指导意义。
我校博士生黄悦、硕士生王晗、高级工程师李廷栋和新密市妇幼保健院李彩红主任医师为该论文的共同第一作者。我校张军教授、葛胜祥教授和美国德克萨斯大学休斯顿健康科学中心傅通明博士为该论文的共同通讯作者。Background:
Universal screening of congenital cytomegalovirus (cCMV) infection is important for monitoring and intervention during critical stages of speech and language development. This study aimed to explore the optimal detection strategy for cCMV infection screening.
Methods:
Serum samples from pregnant women and saliva and urine samples from their newborns were collected for the anti-CMV IgG and CMV DNA PCR tests, respectively. The sensitivity, specificity, and predictive values as well as the likelihood ratios of 12 potential screening strategies for cCMV infection, based on tests for saliva, urine, and their combination, were evaluated.
Findings:
A total of 6729 pregnant women were enrolled, and the seroprevalence was 98.1%. Among 6350 newborns that were followed up, 49 were defined as having cCMV infection. In the screening test, the CMV DNA positivity rate remained similar from day 0 to day 5, increased slowly from day 6 to day 13, and became high in newborns beyond 13 days of birth. In the confirmatory testing, the positive rates increased significantly beyond day 21. For the 49 newborns with cCMV infection, the proportion of agreement between saliva and urine testing was poor. Upon evaluating alternative screening strategies, using saliva and urine screening with saliva and urine confirmation as the reference strategy, saliva screening with saliva and urine confirmation showed good diagnostic accuracy and feasibility, with sensitivity, specificity, positive predictive and negative predictive values of 85.7%, 100.0%, 100.0% and 99.9%, respectively.
Interpretation:
In populations with high seroprevalence, saliva screening with saliva and urine confirmation might be an alternative strategy for screening cCMV infections. The suggested timeframes for screening and confirmation are within 13 (ideally 5) and 21 (ideally 13) days of birth, respectively.This work was supported by the National Natural Science Foundation of China (grants 81973058 and 81672111), the National Science and Technology Major Project of China (2017ZX10302201-002-003) and Merck & Co., Inc., Kenilworth, New Jersey, U.S.A.
该研究获得国家自然科学基金、传染病重大专项、厦门大学校长基金及美国默沙东公司支持
Invisible Gateway by Superscattering Effect of Metamaterials
No full text物体的幻象光学效应是指被观测到的物体和实际物体本身不同的现象。理论证明，超级散射体可以用互补媒质结合变换光学技术加以实现。这一技术已被用来设计许多奇妙有趣的幻象光学器件，然而，要实现这些器件需要有负折射率材料，并对材料折射率的分布提出了苛刻的要求，在实验上极难实现。研究人员通过双负材料构造了微波频段的超级散射体，在实验中首次观测到双负材料的散射放大效应。他们进一步利用制备的超级散射体搭建了电磁隐形门，在1.7倍波长宽度的空气通道内对一定频率范围内的电磁起到了有显著的阻断作用。该工作是幻象光学器件研究的一个重要进展，它将激励和促进其它幻象器件的研究和实现。Illusion devices, such as superscatterer and invisible gateway, have been theoretically studied under the theory of transformation optics and folded geometry transformations. The realization of these devices needs building blocks of metamaterials with negative permittivities and permeabilities. However, superscattering effects, such as stopping wave propagation in an air channel, have not been verified from illusion devices physically because of the challenge of metamaterial design, fabrication, and material loss. In this Letter, we implement a big metamaterial superscatterer, and experimentally demonstrate its superscattering effect at microwave frequencies by field-mapping technology. We confirm that superscattering is originated from the excitation of surface plasmons. Integrated with superscatterer, we experimentally display that an invisible gateway could stop electromagnetic waves in an air channel with a width much larger than the cutoff width of the corresponding rectangular waveguide. Our results provide a first direct observation of superscattering effect of double negative metamaterials and invisible gateway for electromagnetic waves. It builds up an ideal platform for future designs of other illusion devices.This work was supported by National Natural Science Foundation of China (NSFC) (61771237), and partially by the Project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions and Jiangsu Provincial Key Laboratory of Advanced Manipulating Technique of Electromagnetic Waves. H. C. was supported by the National Science Foundation of China (Grant No. 11874311) and would like to celebrate the centennial anniversary of Xiamen University
Opposition between “What Is” and “What Ought to Be”and Exploration of the Path of Sublation：Interpretation of Letter from marx to His Father
No full text潘中伟，郑州大学哲学学院教授、博士生导师，哲学博士；周媛媛，郑州大学马克思主义学院博士研究生。【中文摘要】1837年《给父亲的信》是考察马克思转向黑格尔哲学的重要文本。长期以来,学者们更多是从方法论的方面解释马克思的这一思想转向，即为了解决“现有之物”与“应有之物”的对立,马克思转向黑格尔哲学寻求认识真理的方法,但这一 “寻求” 一定是预设了 “现有之物”与“应有之物”不应当对立的观念。深入分析这一预设，可以发现浪漫主义对于马克思早期思想潜移默 化的深刻影响。马克思不仅从浪漫主义那里接受了“现有之物”与“应有之物”应当统一的看法，而且接受了浪漫主义所提出的通过人的活动实现“现有之物”与“应有之物”相统一的主张。在浪漫主义“诗化生活”思想的启发下,马克思提出了“世界哲学化”与“哲学世界化”的观点，由此奠 了马克思哲学的实践性指向。
【Abstract】Letter from Marx to His Father in 1837 is the important text to study Marx's turn to Hegel philosophy. For a long time，scholars have expounded the change of his thought from the perspective of methodology ：In order to solve the opposition between “what is” and “what ought to be”，Marx sought ways to lean the truth from Hegel philosophy. But such pursuit was certainly based on the assumption that there should be no opposition between “ what is ” and “ what ought to be”. With an in - depth analysis of this assumption， the subtle but profound influence of romanticism on Marx's early thinking can be observed. Marx accepted from romanticism the idea that both “what is” and “what ought to be” must be viewed as a unity，and that they can be united by human practices. Enlightened by romantic thought of poetic life，he made the point that as the world becomes philosophical，philosophy also becomes worldly，which lays the foundation for the practical specialty of Marxist philosophy.国家社会科学基金一般项目“马克思主义意识形态的理论创新研究”（17BKS101) ;2021年度河南省教育厅哲学社会科学基础研究重大项目“马克思《博士论文》释义及其当代价值研究”（2021-JCZD-10
Compilation of Anthology and Construction of the “Misty Peotry School”
No full text徐勇，厦门大学中文系教授、博士生导师。【中文摘要】从文学史的角度看，朦胧诗文学史地位的确立，既与当时引起的争论密不可分，也是各种诗歌选本所共同建构的产物。但不同阶段，关于朦胧诗的构成和指向是不同的。如果说20世纪80年代中前期的“朦胧诗”的相关选本是在构筑思潮意义上的“朦胧诗”，80年代中后期以来的相关选本，则是在参与文学史意义上和风格意义上的“朦胧诗”的构筑。
【Abstract】From the perspective of literary history，the establishment of the status of misty poetry in literary history was not only inseparable from the debate at that time，but also the product of the joint construction of various poetry anthologies. But at different stages，the composition and direction of misty poetry were different. If the anthologies related to “misty poetry”in the early and mid-1980s were constructing “misty poetry” in the sense of ideological trend，the related anthologies since the early and mid-1980s have been participating in the construction of “misty poetry” in the sense of literary history
and style.国家社会科学基金后期资助项目“中国当代新诗选本研究”（19FZWB048
A Study of the Dependence of Taiwan's Advanced Manufacturing Industry on the Chinese Mainland's Economy
No full text李非，厦门大学台湾研究院特聘教授、博士生导师；王辉辉,厦门大学台湾研究院博士研究生。【中文摘要】先进制造业是台湾经济全球竞争力的关键,也是当前海峡两岸产业深度对接的重点。研究台湾先进制造业对中国大陆经济的依赖度,对推动两岸先进制造业发展、建立共同市场携手融入“双循环”具有重要意义。基于进出口及投资三个层面考察中国大陆经济在台湾先进制造业发展中的地位，可分析台湾先进制造业对中国大陆经济的依赖度及发展空间。无论贸易往来还是投资流向，均显示出台湾先进制造业已形成以中国大陆为中心、难以分割的体系，且对中国大陆经济的依赖度呈现增加趋势。台湾先进制造业对中国大陆经济的依赖及发展空间为深化两岸先进制造业合作、有效推进两岸共同市场的建构提供了可能和努力的方向。
【Abstract】Taiwan's advanced manufacturing industry is essential to the global competitiveness of its economy，as well as the focus of the deep matching-up of industries across the Taiwan Strait. It is of great significance to study the dependence of Taiwan's advanced manufacturing industry on the Chinese Mainland's economy. The study will promote efforts to develop advanced manufacturing across the Taiwan Strait and establish a common market for integration into the “dual circulation” development pattern. Based on the three levels-import，export and investment，the study examines the position of the Chinese Mainland's economy in the development of Taiwan's advanced manufacturing industry，and analyzes the dependence of Taiwan's advanced manufacturing industry on the Chinese Mainland's economy and its space for development. For both the flow of trade and investment，the study shows that Taiwan's advanced manufacturing industry has formed an indivisible system centered on the Chinese Mainland，and its dependence on the Chinese Mainland's economy is showing an upward trend. The dependence of Taiwan's advanced manufacturing industry on the Chinese Mainland's economy，and the space for the development of the industry，provide possibilities and directions for efforts to deepen advanced manufacturing cooperation across the Taiwan Strait，and effectively promote the construction of a cross-Strait common market.国家社会科学基金重大项目“打造两岸共同市场、壮大中华民族经济研究”（21ZDA127
Synthesis of Nickel Phosphide/Nitrogen Phosphorus Co-Doped Carbon and Its Application in Lithium Ion Batteries
No full text以离子液体为碳源和氮源、次亚磷酸钠为磷源、乙酸镍为镍源,一步法制备了磷化镍/氮磷共掺杂碳(Ni2P/NPC)复合材料。SEM、TEM等检测结果表明Ni2P纳米颗粒在N、P共掺杂碳骨架上均匀分布。将所制备Ni2P/NPC作为锂离子电池负极材料时,Ni2P/NPC电极在0.1、0.5、1、3和5 A·g-1电流密度下的放电比容量分别为377.7、 294.1、 265.4、211.7和187.5 mAh·g-1。当电流密度重新回到0.1 A·g-1,放电比容量为368.1 mAh·g-1。电极结构在大倍率下可以保持稳定,表现出优异的倍率性能。在0.5 A·g-1的电流密度下经200次循环后放电比容量维持在301.8 mAh·g-1,容量保持率为80.7%,CV曲线证实Ni2P/NPC在储锂过程中是由扩散过程和电容行为共同控制。In recent years, the nickel-based phosphide has drawn great attention because of its low intercalation/deintercalation platform and lower polarization compared to sulfides and oxides as anodes for next-generation high-energy lithium-ion batteries. The Ni2P anode can deliver high theoretical specific capacity of 542 mAh·g-1, but it subject to a conversion reaction mechanism, which make them unsuitable for commercial applications. The agglomeration of Ni2P nanoparticles during material fabrication and the structural deterioration of electrode associated with large volume change during charge-discharge process lead to poor cycle stability and low utilization of active materials. Meanwhile, the low intrinsic conductivity of Ni2P is also sluggish electrochemical reaction kinetics. Herein, we design a facile and viable approach to synthesize Ni2P/NPC composites with a stable structure to address these issues. This new approach entails synthesis of Ni2P/NPC by a N and P co-doped carbon framework with ionic liquids assistance during synthesis. This stable composite structure can serve as anode material of lithium ion batteries with good electrochemical performance. The Ni2P/NPC composites were prepared by one-step method using ionic liquids as carbon and nitrogen sources, while sodium hypophosphite and nickel acetate as phosphorus and nickel sources, respectively. The results of SEM and TEM show that Ni2P nanoparticles were uniformly distributed on the N and P co-doped carbon framework. When the Ni2P/NPC composite was used as an anode material of lithium ion batteries, the discharge specific capacities were 377.7, 294.1, 265.4, 211.7 and 187.5 mAh·g-1 at 0.1, 0.5, 1, 3 and 5 A·g-1, respectively. When the current density returned to 0.1 A·g-1, the discharge specific capacity reached 368.1 mAh·g-1. The Ni2P/NPC structure could be kept stable at high rate, showing excellent rate performance. The fabricated Ni2P/NPC anode delivered the discharge specific capacity of 301.8 mAh·g-1 with the capacity retention of 80.7% after 200 cycles at 0.5 A·g-1. Finally, CV curves confirmed that the lithium storage of Ni2P/NPC colud be controlled by diffusion process and capacitance behavior.国家自然科学基金项目(51404124);省部共建有色金属先进加工与再利用国家重点实验室开放基金(SKLAB02019015)通讯作者:蒙延双E-mail:[email protected]:Yan-ShuangMengE-mail:[email protected]兰州理工大学材料科学与工程学院,甘肃 兰州 730000School of Materials Science and Engineering, Lanzhou University of Technology,Lanzhou 730000, Gansu Chin
“Who Am I”：A Study of the Identity of Chinese Elders in the U.S.：An Anthropological Study of Chinese Elders in Michigan
No full text田烨，兰州大学西北少数民族研究中心/历史文化学院教授、博士生导师；马文，兰州大学西北少数民族研究中心/历史文化学院博士研究生，日本首都大学东京人文社会学部客座研究员。【中文摘要】身份认同是个难以界定的复杂问题,基于前人的相关研究经验,可以通过居住区域、社会交往、生活方式以及国家认同、文化认同、族群归属等外在行为和心理认同两方面对美国老年华人群体身份认同进行界定。实地调研发现,与中青年华人群体不同，美国老年华人的居住区域、社会交往以及生活方式等方面有着自身的特点,这些显现于外的特征体现了老年华人群体的身份认同，之所以更喜欢居住于华人社区、更倾向于与华人交往、更多地保留了国内生活习惯,这与老年华人群体隐藏于内的国家认同、文化认同和归属意识的有着直接的关系。老年华人群体对中华民族和中华文化的高度认同，有利于传承和发扬中华传统文化，加强海外华人群体的中华民族身份认同 。
【Abstract】Identity is a complex issue which is difficult to define. Based on previous research experience，this study attempts to analyze the identity of Chinese elders in the United States in terms of behavioral and psychological identity. Based on existing studies and field research，we specifically look at their place of residence，social interaction，lifestyle，national identity，cultural identity and ethnic group identity. Evidence captured from field work shows that Chinese elders have their own characteristics in terms of living area，social interaction and lifestyle，which are different from those of young and middle - aged Chinese in the U. S. These external characteristics reveal the identity of Chinese elders in field work. We have also found that Chinese elders prefer to live in Chinese communities，are inclined to communicate with fellow Chinese ，and retain their original living habits，driven by their national identity，cultural identity and ethnic group identity. Chinese elders ’ high recognition of the Chinese nation and Chinese culture is conducive to inheriting and carrying forward traditional Chinese culture and strengthening the identity of the Chinese nation among overseas Chinese groups.国家社会科学基金重点项目“欧盟少数民族事务治理研究”(19AMZ014