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Anomalous Transport Characteristics of High Temperature Superconductors and Josephson Currents

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Communications in Theoretical Physics 2002年第3期38卷 379-384页

作者： LIANG Fang-ying LI zuo-hong Institution of Science and Technology for OPTO-Electronic Information Yantai University Yantai 26400 Shangdong Province China Institution of Science and Technology for OPTO-Electronic Information Yantai University Yantai 26400 Shangdong Province China

The transport characteristics of high temperature superconductor current and Josephson current is inves-tigated in the framework of the modified time-dependent Ginzburg-Landau model and the Lawrence-Doniach *** evaluated the vortex equation and found that the signs of the high temperature superconductor current and theJosephson current can reverse. Some explicit expressions for different cases are derived, which accord with experimentaldata.

关键词： superconductivity, junction, Josephson current

Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第1期68卷 288-296页

作者： Shuai Liu Wen-Qiang Xu ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang Zhi-Li zuo Han Guo Zi-Fei Xu ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： ying Wang Kai Zhang Liping Ding Liyun Wu Songfeng E Qian He Nanyang Wang Hui zuo Zhengyang Zhou Feng Ding Yue Hu Jin Zhang Yagang Yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of Electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials Engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular Engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory

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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激光在现代农业及生物科学中的应用

天津农学院学报 2002年第1期9卷 55-58页

作者：高映宏左颖天津农学院农业工程系天津300384

激光自诞生以来,其在农业和生物科学以及其它诸多领域中得到了日益广泛的应用,并获得了巨大的成功。本文对激光进行了概述并从激光作用于生物有机体的效应这个角度阐述了应用于农业领域的激光技术。

关键词：激光激光生物效应激光应用现代农业生物科学

Vector meson's spin alignments in high energy reactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 5-20页

作者： Jin-Hui Chen zuo-Tang Liang Yu-Gang Ma Xin-Li Sheng Qun Wang Key Laboratory of Nuclear Physics and Ion-beam Application (MoE) Institute of Modern PhysicsFudan University Institute of Frontier and Interdisciplinary Science Key Laboratory of Particle Physics and Particle Irradiation (MOE)Shandong University INFN-Firenze Department of Modern Physics University of Science and Technology of China School of Mechanics and Physics Anhui University of Science and Technology

The global spin alignment of vector mesons has been observed by the STAR collaboration at the Relativistic Heavy Ion Collider （RHIC） at Brookhaven National Laboratory （BNL）.It provides a unique opportunity to probe the correlation between the polarized quark and antiquark in the strongly coupled quark-gluon plasma （sQGP） produced in relativistic heavy ion collisions,opening a new window to explore the properties of s *** addition,spin alignments of vector mesons have also been observed in other high-energy particle collisions such as e+e-annihilations at high energies where hadron production is dominated by quark fragmentation *** results obtained are quite different from those obtained in heavy ion collisions where quark coalescence/combination mechanism dominates suggesting strong dependence on hadronization *** comprehensive studies in different hadronization processes are *** this article,we present a brief review of theoretical and experimental advances in the study of vector meson’s spin alignments in a variety of high-energy particle collisions,with emphasis on hadronization mechanisms.

关键词： vector meson spin alignment global polarization relativistic heavy ion collisions fragmentation

Non-existence of Shimura curves of Mumford type generically in the non-hyperelliptic locus

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Science China Mathematics 2025年

作者： Xin Lü Shengli Tan Kang zuo School of Mathematical Sciences Key Laboratory of Mathematics and Engineering Applications(Ministry of Education) Shanghai Key Laboratory of Pure Mathematics and Mathematical PracticeEast China Normal University School of Mathematics and Statistics Wuhan University Institut für Mathematik Universit?t Mainz

We show that there does not exist any Shimura curve with a strictly maximal Higgs field generically in the Torelli locus of non-hyperelliptic curves of genus g≥4. In particular, Shimura curves of Mumford type are not...

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An Unprecedented Efficiency with Approaching 21%Enabled by Additive‑Assisted Layer‑by‑Layer Processing in Organic Solar Cells

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Nano-Micro Letters 2025年第2期17卷 372-375页

作者： Shuai Xu Youdi Zhang Yanna Sun Pei Cheng Zhaoyang Yao Ning Li Long Ye Lijian zuo Ke Gao Key Laboratory of Advanced Green Functional Materials College of ChemistryChangchun Normal UniversityChangchun 130032People’s Republic of China Shandong Provincial Key Laboratory for Science of Material Creation and Energy Conversion School of Chemistry and Chemical EngineeringShandong UniversityQingdao 266237People’s Republic of China College of Polymer Science and Engineering Sichuan UniversityChengdu 610065People’s Republic of China State Key Laboratory and Institute of Elemento‑Organic Chemistry Centre of Nanoscale Science and Technology and Key Laboratory of Functional Polymer MaterialsRenewable Energy Conversion and Storage Center(RECAST)College of ChemistryNankai UniversityTianjin 300071People’s Republic of China Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and Devices South China University of TechnologyGuangzhou 510640People’s Republic of China Tianjin Key Laboratory of Molecular Optoelectronic Sciences School of Materials Science and EngineeringTianjin UniversityTianjin 300350People’s Republic of China State Key Laboratory of Silicon Materials MOE Key Laboratory of Macromolecular Synthesis and FunctionalizationDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China

Recently published in Joule,Feng Liu and colleagues from Shanghai Jiaotong University reported a record-breaking 20.8%power conversion efficiency in organic solar cells(OSCs)with an interpenetrating fibril network active layer morphology,featuring a bulk p-in structure and proper vertical segregation achieved through additive-assisted layer-by-layer *** optimized hierarchical gradient fibrillar morphology and optical management synergistically facilitates exciton diffusion,reduces recombination losses,and enhances light capture *** approach not only offers a solution to achieving high-efficiency devices but also demonstrates the potential for commercial applications of OSCs.

关键词： Organic solar cells Additive-assisted layer-by-layer processing Three-dimensional fibril morphology Bulk p-i-n structure Optical management

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数据规制对制造业全球价值链韧性的影响

中国流通经济 2025年第1期39卷 62-75页

作者：殷红左舒雅辽宁大学国际经济政治学院辽宁沈阳110000

数据规制作为缓解数据市场失灵和提升数据安全的政策工具,加速数字经济对全产业链的渗透和融合,促进制造业参与生产分工机会的公平化与多元化,推动全球价值链分工演进。在多重不确定性因素引发全球价值链重构背景下,数据规制能否成为增... 详细信息

数据规制作为缓解数据市场失灵和提升数据安全的政策工具,加速数字经济对全产业链的渗透和融合,促进制造业参与生产分工机会的公平化与多元化,推动全球价值链分工演进。在多重不确定性因素引发全球价值链重构背景下,数据规制能否成为增强制造业全球价值链韧性的制度保障成为重要议题。基于2007—2021年38个国家的数据规制政策条款,测算出这些国家的数据规制水平。基于价值链长度等数据,从安全性和稳定性两个维度测算出这些国家16个制造行业的GVCs韧性。利用该面板数据,通过双向固定效应和中介效应模型,定量分析数据规制对制造业价值链韧性的影响与机制。研究发现,数据规制能够显著提升制造业全球价值链韧性,但提升效果存在着边际递减特征,该结论在替换核心变量衡量指标、引入制度遗漏变量、考虑政策传递时滞、进行内生性处理后依然稳健。数据规制政策对制造业价值链韧性的提升作用具有异质性,该驱动作用在商业数据与知识产权数据流通量较大的资本与技术密集型制造业中、市场与创新环境处于成长阶段的发展中国家中、更注重数据主体隐私维护的欧式和中式规制的国家中更为显著,且管制国内数据对价值链韧性所产生的影响大于管制跨境数据。数据规制可增强企业间的数据信任,通过网络连接效应和生产协同效应对制造业价值链韧性产生直接影响,并通过扩大市场规模、降低贸易成本、促进技术创新三种渠道间接提升制造业价值链韧性。因此,为有效推进数据治理及维护价值链安全,应规范数据交易规则与收益分配,促进数据有效流通;完善数据治理的功能性配套措施和精细化管理,发挥数据要素规模对价值链韧性的倍增作用;坚持参与国际数据规则的制定,建立有效的跨境数据安全评级系统。

关键词：数据规制全球价值链韧性市场规模贸易成本技术创新