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理论探索二维X_(2)UO_(4)(X=K,Rb,Cs)的力学特征、电子结构和声子输运特征

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原子与分子物理学报 2025年第2期42卷 143-150页

作者：程钧湖北医药学院研究生院十堰442000

本文用基于密度泛函理论的第一性原理计算方法,研究了三种建议的二维材料X_(2)UO_(4)(X=K,Rb,Cs)的稳定性、弹性、电子结构和声子振动特性.计算结果显示,三种材料同时具备较好的热力学、动力学和机械稳定性.电子结构表明,三种材料属于... 详细信息

本文用基于密度泛函理论的第一性原理计算方法,研究了三种建议的二维材料X_(2)UO_(4)(X=K,Rb,Cs)的稳定性、弹性、电子结构和声子振动特性.计算结果显示,三种材料同时具备较好的热力学、动力学和机械稳定性.电子结构表明,三种材料属于宽禁带间接半导体,其计算能隙分别是3.90、3.79和3.42 eV,并且在300 K时有着71.31-174.23 cm^(2)/Vs的电子迁移率.声子输运特性表明,三种材料的声子色散均没有虚频出现,声学模和低频光学模呈现强烈耦合,且有着低频率low-lying声子,这使得材料具备很强的声子非谐效应、低声子群速度和强声子散射率,从而表现出很低晶格热导率,在300 K温度下时仅为0.16-0.19 W/mK.这些特性表明,二维X_(2)UO_(4)(X=K,Rb,Cs)在纳米电子和热电器件领域具备应用潜力.

关键词：二维材料能带迁移率声子热导率

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监护人责任的实体法与程序法问题

北京理工大学学报（社会科学版） 2025年第1期27卷 21-34页

作者：程啸清华大学法学院北京100084

监护人责任属于替代责任。监护人是侵权责任的主体,应当直接向被侵权人承担全部的侵权责任,而非相应的责任或补充责任。《民法典》第1188条第2款要求从有财产的被监护人的财产中支付赔偿费用,不足的部分才由监护人赔偿,该规定过于保护... 详细信息

监护人责任属于替代责任。监护人是侵权责任的主体,应当直接向被侵权人承担全部的侵权责任,而非相应的责任或补充责任。《民法典》第1188条第2款要求从有财产的被监护人的财产中支付赔偿费用,不足的部分才由监护人赔偿,该规定过于保护被侵权人以及监护人,忽视对被监护人的保护。父母作为未成年子女的法定监护人应当共同承担监护人责任即承担的是连带责任。离异夫妻中未与未成年人子女共同生活的一方也应当承担全部的监护人责任。没有与继子女形成抚养教育关系的继父母不承担监护人责任。继父母收养继子女后,应当承担监护人责任,被监护人的生父母不再承担监护人责任。教唆人、帮助人的侵权责任与未尽到监护职责的监护人承担的相应的责任以及监护人与有过错的受托履行监护职责的人所承担的侵权责任的关系都属于部分的连带责任。在监护人责任诉讼中监护人与被监护人属于共同被告。

关键词：民法典监护人责任补充责任相应的责任部分连带责任

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现代性与时间逻辑中的“新异化”--重审罗萨的社会加速批判理论

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北京理工大学学报（社会科学版） 2025年第1期27卷 188-196页

作者：程萌武汉大学哲学学院湖北武汉430072

作为法兰克福学派新一代的代表人物,罗萨一方面继承霍克海默、哈贝马斯等从工具理性的角度批判资本主义社会对人的奴役的思想传统,一方面又试图在现代社会加速层面系统说明人类在现代自然科学的迷信下追求“掌控世界”造成人与世界关系... 详细信息

作为法兰克福学派新一代的代表人物,罗萨一方面继承霍克海默、哈贝马斯等从工具理性的角度批判资本主义社会对人的奴役的思想传统,一方面又试图在现代社会加速层面系统说明人类在现代自然科学的迷信下追求“掌控世界”造成人与世界关系相扭曲的“新异化”。在他看来,这种异化不同于马克思的异化劳动,而是植根于现代性加速进程中时间结构改变的“空间异化”“物的异化”“行动异化”“时间异化”以及“自我异化”。时间不再单纯是描述物质运动持续历程的物理参数,而是全面介入现代社会结构和人的生活内容。加速社会凭借不断强化的时间逻辑,固然提高生产生活效率,但又导致人们不得不持久地加入对各种资源的竞争追逐,生活节奏越来越快,质量越来越差。为克服弊端,罗萨提出当前应引入新的追求“质”的提升的“后增长社会”的发展模式,建构人与世界共鸣关系的美好生活。从马克思的历史唯物主义来看,罗萨为分析资本主义社会的危机提供新思路,然而又未意识只有将现代性逻辑、加速逻辑置于资本逻辑的场域中,立足于变革生产方式的维度,实现“自然科学”与“人的科学”的统一,才能真正消解加速社会中人的异化情形。

关键词：现代性异化时间结构社会加速共鸣关系生产方式变革

Pronounced impact of size and shape effects on creep rupture life of a K439B superalloy combustion chamber casting simulator

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China Foundry 2025年

作者： Wen-tong Liu Yi-dong Wu Lei Gao Jing-yang Chen cheng-bo Xiao Xi-dong Hui State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical Materials

The size and shape effect(SSE) of components has become a critical issue for mechanical properties, application reliability, and processing. In this study, the creep rupture life(CRL) of components with different wall thicknesses and positions in a combustion chamber casing simulator made of K439B superalloy was investigated. The intrinsic mechanisms of the SSE were explored from the dendrite structure, volume fraction and size of the γ' phase, and element segregation, etc. It is shown that this casting exhibits a strong SSE of creep rupture life, characterized by a significant difference in the CRL values up to 60% with the variation of wall thickness and position in the casing. In terms of casting technology, the influence of SSE on CRL is actually determined by the cooling rate. The SSE on the creep rupture life originates from the dendrite structure(such as the secondary dendrite arm spacing), volume fraction size of the γ' phase in the dendrite trunk, and elements segregation rate. This work may have implications for the design and application of engineering components with large sizes and complex structures.

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Achieving ultralow leakage current in Schottky-MIS cascode anode lateral field-effect diode based on AlGaN/GaN HEMT

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Science China(Information Sciences) 2025年第1期68卷 379-385页

作者： Fangzhou WANG Changhong GAO Guojian DING cheng YU Zhuocheng WANG Xiaohui WANG Qi FENG Ping YU Peng ZUO Wanjun CHEN Yang WANG Haiqiang JIA Hong CHEN Bo ZHANG Zeheng WANG Songshan Lake Materials Laboratory School of Microelectronics Southern University of Science and Technology State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China Manufacturing Commonwealth Scientific and Industrial Research Organisation

In this paper,we design and fabricate a Schottky-metal-insulator-semiconductor（MIS） cascode anode GaN lateral field-effect diode（CA-LFED） to achieve ultralow reverse leakage current(ILEAK).The device based on AlGaN/GaN highelectron-mobility-transistor（HEMT） includes a normally-off MIS-controlled channel that is cascoded with a high barrier height Schottky *** reverse bias,the high electric-field is effectively prevented by the normally-off MIS-controlled channel *** with the high barrier height Schottky contact,this feature significantly suppresses the *** by the device fabrication,the CA-LFED with high breakdown voltage（BV）>600 V shows an ultralow ILEAKof 3.6×10-9A/mm as well as a low forward voltage drop（VF） of 2.2 *** performance suggests that the CA-LFED can be a promising candidate for ultralow ILEAKand better VF-ILEAKtrade-off GaN power diode applications.

关键词： Schottky-MIS cascode anode lateral field-effect diode (LFED) ultralow reverse leakage current ($I_{\rm{LEAK}}$) forward drop and reverse leakage trade-off AlGaN/GaN HEMTs

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Catalytic atroposelective synthesis of indolyl quinazolinones bearing N-N/C-C diaxes

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Science China Chemistry 2025年

作者： Ning-Yi Wang Shuo Gao Zhu-Di Shu Bei-Bei cheng Chun Ma Yu-Chen Zhang Feng Shi Research Center of Chiral Functional Heterocycles School of Chemistry and Materials Science Jiangsu Normal University School of Petrochemical Engineering Changzhou University School of Chemistry and Chemical Engineering Henan Normal University

The first catalytic atroposelective synthesis of indole derivatives bearing N-N/C-C diaxes has been established by the strategy of de novo ring formation. By this strategy, various indolyl quinazolinones bearing vicinal N-N/C-C diaxes were synthesized in high yields with overall good diastereoselectivities and excellent enantioselectivities via chiral phosphoric acid-catalyzed onepot asymmetric formal (5+1) cycloaddition/oxidation reaction. Moreover, such indolyl quinazolinones bearing vicinal N-N/CC diaxes have good configurational stability and could be converted into new chiral ligands with applications in asymmetric catalysis. Therefore, this work not only offered a new member for the family of diaxial atropisomers, but also provided a powerful strategy for catalytic asymmetric synthesis of atropisomers bearing N-N/C-C diaxes.

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Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期68卷 46-95页

作者： Zhong-Liang Gong Hong-Jie Zhang Yan cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin Xu Yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

关键词： photoactive metal complexes earth-abundant metals nonprecious metal complexes luminescence photochemistry

A novel flexible nerve guidance conduit promotes nerve regeneration while providing excellent mechanical properties

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Neural Regeneration Research 2025年第7期20卷 2084-2094页

作者： Tong Li Quhan cheng Jingai Zhang Boxin Liu Yu Shi Haoxue Wang Lijie Huang Su Zhang Ruixin Zhang Song Wang Guangxu Lu Peifu Tang Zhongyang Liu Kai Wang Department of Orthopedics the Fourth Medical Center of Chinese PLA General HospitalBeijingChina Department of Training and Sports Medicine Characteristic Medical Center of Chinese People’s Armed Police ForceTianjinChina Medical School of Chinese PLA BeijingChina Key Laboratory of Bioactive Materials for the Ministry of Education College of Life SciencesNankai UniversityTianjinChina Department of Orthopedics Tianjin HospitalTianjinChina Department of Rehabilitation Medicine Er Quan Hospital of PAPWuxiJiangsu ProvinceChina

Autografting is the gold standard for surgical repair of nerve defects>5 mm in length;however,autografting is associated with potential complications at the nerve donor *** an alternative,nerve guidance conduits may be *** ideal conduit should be flexible,resistant to kinks and lumen collapse,and provide physical cues to guide nerve *** designed a novel flexible conduit using electrospinning technology to create fibers on the innermost surface of the nerve guidance conduit and employed melt spinning to align ***,we prepared disordered electrospun fibers outside the aligned fibers and helical melt-spun fibers on the outer wall of the electrospun fiber *** presence of aligned fibers on the inner surface can promote the extension of nerve cells along the *** helical melt-spun fibers on the outer surface can enhance resistance to kinking and compression and provide *** novel conduit promoted nerve regeneration and functional recovery in a rat sciatic nerve defect model,suggesting that it has potential for clinical use in human nerve injuries.

关键词： aligned fibers anti-kinking helical fibers nerve guidance conduit nerve regeneration peripheral nerve injury topological guidance

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Ni-catalyzed cross-electrophile alkyl-alkyl coupling reactions

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Science China Chemistry 2025年

作者： Li-Xu You Lan Tian Chun-Ling Guo Shun-Xi Li Yu-cheng Liu Yu-Long Li Wei Shu College of Chemistry and Environmental Engineering Key Laboratory of Green Catalysis of Higher Education Institutes of Sichuan Sichuan University of Science and Engineering Guangming Advanced Research Institute Shenzhen Grubbs Institute Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and Technology

Introducing saturated carbon-carbon bonds into organic molecules significantly increases the three-dimensional configuration,thus altering the physical and chemical properties as well as the functions of molecules. Transition-metal-catalyzed carboncarbon cross-couplings represent one of the most straightforward, efficient and modular alternatives to build saturation in a single step. However, the efficient construction of alkyl-alkyl bonds remains a formidable challenge due to the precise manipulation of multiple alkyl metallic intermediates as well as associated competitive side reactions and selectivity control. Over the past years, Ni-catalyzed cross-coupling under reductive conditions has gained more and more attention for alkyl-alkyl crosscoupling partially attributing to the low-valent state of metal centers under reducing conditions, which suppresses the competitive β-hydride elimination process, thus facilitating the formation of alkyl-alkyl bonds. In this review, the initiative and progress of Ni-catalyzed cross-electrophile alkyl-alkyl cross-coupling, including the efforts in racemic and enantioselective formation of alkyl-alkyl bonds, have been summarized and discussed. Moreover, the challenges and further opportunities in this area have also been discussed.

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