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Electrical transport and optical properties of Cd3As2 thin films

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Chinese Physics B 2019年第10期28卷 93-100页

作者： Yun-Kun Yang fa-xian Xiu Feng-Qiu wang Jun wang Yi Shi Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China State Key Laboratory of Surface Physics and Department of Physics Fudan UniversityShanghai 200433China School of Electronic Science and Engineering Nanjing UniversityNanjing 210093China School of Optoelectronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054China State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of ChinaChengdu 610054China National Laboratory of Solid State Microstructures School of PhysicsNanjing UniversityNanjing 210093China

Cd3As2, as a three-dimensional(3D) topological Dirac semimetal, has attracted wide attention due to its unique physical properties originating from the 3D massless Dirac fermions. While many efforts have been devoted to the exploration of novel physical phenomena such as chiral anomaly and phase transitions by using bulk crystals, the development of high-quality and large-scale thin films becomes necessary for practical electronic and optical applications. Here, we report our recent progress in developing single-crystalline thin films with improved quality and their optical devices including Cd3As2-based heterojunctions and ultrafast optical switches. We find that a post-annealing process can significantly enhance the crystallinity of Cd3As2 in both intrinsic and Zn-doped thin films. With excellent characteristics of high mobility and linear band dispersion, Cd3As2 exhibits a good optical response in the visible-to-mid-infrared range due to an advantageous optical absorption, which is reminiscent of 3D graphene. It also behaves as an excellent saturable absorber in the mid-infrared regime. Through the delicate doping process in this material system, it may further open up the long-sought parameter space crucial for the development of compact and high-performance mid-infrared ultrafast sources.

关键词： topological Dirac semimetals thin films photodetectors ultra-fast optical switches

Ruthenium (II)-catalyzed synthesis of phthalides via the cascade addition and cyclization of aromatic acids with aldehydes

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Science China Chemistry 2018年第2期61卷 153-158页

作者： Juan fan Peng-Min wang Jia-Ni wang Xue Zhao Zhong-Wen Liu Jun-fa Wei xian-Ying Shi Key Laboratory for Macromolecular Science of Shaanxi Province School of Chemistry and Chemical EngineeringShaanxi Normal University

The ruthenium-catalyzed intermolecular cascade cyclization of aromatic acids with aromatic aldehydes, which involves the direct insertion of C–H bond into a polar C=O bond and the successive intramolecular nucleophilic substitution, was developed for the synthesis of 3-substituted phthalides in good to excellent yields. This one-pot procedure characterizes in a short reaction time, the cheaper Ru(II) as a catalyst, readily available acids and aldehydes as starting materials, and water as the only theoretical *** merits make the protocol an efficient and cost-effective route for the synthesis of 3-substituted phthalides.

关键词： nucleophilic addition cascade cyclization ruthenium 3-substituted phthalides C–H activation

Recent progress in metal-organic frameworks(Part II—material application)

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Science China Chemistry 2025年

作者： Jiandong Pang Wentao Jiang Xue-Wen Zhang Hao-Long Zhou Yuxiu Sun Wei Gong Bin wang Fuyin Ma Linwei He Long Chen Qiang Chen He-Qi Zheng Yuanjing Cui Wen-Jie Shi Chao Zhang Mei wang Yue-Biao Zhang Jie-Peng Zhang Chongli Zhong Yong Cui Shuao wang Jian-Rong Li Guodong Qian Tong-Bu Lu Huan Pang xian-He Bu Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and Engineering Tianjin University of Technology School of Chemistry and Chemical Engineering Yangzhou University School of Materials Science and Engineering Nankai University School of Physical Science and Technology ShanghaiTech University MOE Key Laboratory of Bioinorganic and Synthetic Chemistry GBRCE for Functional Molecular Engineering School of Chemistry IGCMESun Yat-sen University Department of Chemistry Shantou University School of Chemical Engineering and Technology Tiangong University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University State Key Laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences Soochow University College of Materials Science & Engineering Beijing University of Technology State Key Laboratory of Silicon and Advanced Semiconductor Materials Cyrus Tang Center for Sensor Materials and ApplicationsSchool of Materials Science & Engineering Zhejiang University

As a class of functional crystalline porous materials, metal-organic frameworks(MOFs) gained rapid development in the past three decades and a large number of MOFs with ordered structures, high surface areas, and functionalized channels have been investigated. MOFs and MOF-derived/composite materials show great potential in many application fields. In this review, we discussed the main applications of MOFs and MOF-derived/composite materials in small molecule storage, separation, luminescence, sensing, multitype catalysis, and energy storage. In addition, challenges and problems in the future research of MOFsrelated fields are also discussed.

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Generating electron spin qubit in metal-organic frameworks via spontaneous hydrolysis

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Chinese Chemical Letters 2024年第7期35卷 529-533页

作者： xian-fa Jiang Chongyun Shao Zhongwen Ouyang Zhao-Bo Hu Zhenxing wang You Song State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Wuhan National High Magnetic Field Center&School of Physics Huazhong University of Science and TechnologyWuhan 430074China Chaotic Matter Science Research Center Faculty of Materials Metallurgy and ChemistryJiangxi University of Science and TechnologyGanzhou 341000China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China Jiangxi Provincial Key Laboratory of Functional Molecular Materials Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China

Qubit,as the basic unit of quantum operations,has at least two quantum states for *** itself has no superimposable quantum states,but after injecting N atoms,the resulted nitrogenvacancy centers form excellent-performance *** the same purpose,we can also obtain qubits by modifying the matrix without effective quantum ***-1({Cu_(3)(BTC)_(2)(H_(2)O)_(3)},BTC=1,3,5-benzene-tricarboxylate)with S=0 ground state is electron paramagnetic resonance(EPR)silent,so it is not a qubit ***,the spontaneously hydrolyzed HKUST-1 produces dilute uncoupled Cu^(Ⅱ)ions with S=1/*** this paper,we utilized the hydrolysis products of HKUST-1 to obtain qubits and assembled a core-shell structural HKUST-1@ZIF-8 by ZIF-8({Zn(mim)_(2)},mim=2-methylimidazole)coated over HKUST-1 for controlling the *** experimental results clearly show that the qubits come from hydrolyzed Cu^(Ⅱ)***,the dilute uncoupled Cu^(Ⅱ)ions in this assembly can effectively reduce the decoherence of *** EPR studies show that the T_(2) of this compound is 1067 ns at 10 K.

关键词： Hydrolysis Qubit Decoherent times Metal-organic framework Core-shell structure

Associations of Sedentary Time and Physical Activity with Metabolic Syndrome among Chinese Adults:Results from the China Health and Nutrition Survey

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Biomedical and Environmental Sciences 2021年第12期34卷 963-975页

作者： BAI Jing wang Yun ZHANG xian fan OUYANG Yi Fei ZHANG Bing wang Zhi Hong DU Shu fa wang Hui Jun National Institute for Nutrition and Health Chinese Center for Disease Control and PreventionBeijing 100050China Department of Nutrition and Carolina Population Center University of North Carolina at Chapel Hill 123 W.Franklin St.Chapel Hill NC 27599USA

Objective This study aimed to determine the independent and joint associations of sedentary time(ST)and physical activity(PA) with metabolic syndrome(MetS) and its components among Chinese *** The study analyzed data from 4,865 adults aged ≥ 18 years who participated in the 2009 and2015 China Health and Nutrition Surveys(CHNS). Four types of leisure ST and three types of PA selfreported at baseline were collected. Multivariable logistic regressions were used to determine the independent and joint associations of ST and PA with the odds of MetS or its *** For independent effects, higher levels of television time and total leisure ST was associated with higher MetS risk [odds ratio(OR) 1.3, 95% confidence interval(CI) 1.1–1.6, P 7 hours/week(h/w) group was higher than that in the < 7 h/w group in(OR 1.5, 95% CI 1.2–1.9). Higher levels of moderate-to-vigorousintensity physical activity(MVPA) and total PA were associated with a lower MetS risk(OR 0.7, 95% CI0.6–0.9, P < 0.001;OR 0.8, 95% CI 0.7–0.9, P < 0.001, respectively). For the joint effects, compared with those reporting the lowest level of total leisure ST(< 14 h/w) and the most active tertile of MVPA(≥ 61.0 MET-h/w), participants reporting the most total leisure ST(≥ 35 h/w) and the lowest level of MVPA(0 MET-h/w) had the highest odds of MetS(OR 2.0;95% CI 1.4–2.7). Except for people reporting ST(14–21 h/w) within the most active tertile of MVPA, the associations in all other groups were *** the increase of TV time and decreased MVPA, the odds of MetS almost showed a curve *** MVPA and total PA have independent preventive effects, and sedentary behavior(mainly watching TV) has an unsafe effect on MetS and its components. Strengthening the participation of MVPA and combining the LPA to replace the TV-based ST to increase the total PA may be necessary to reduce t

关键词： Sedentary time Physical activity Metabolic syndrome Adults

Fe_(0.02)/Ag_(x)-ZnO复合材料的合成及其光催化活性

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陕西科技大学学报 2025年第1期43卷 88-100页

作者：王远港王有杰孙铖赵显一渤海大学化学与材料工程学院辽宁锦州121013 锦州晨晟科技有限公司辽宁锦州121013

采用水热合成法及煅烧法,制备了不同掺杂量的Fe_(0.02)/Ag_(x)-ZnO复合材料,并考察了各催化剂对RhB光催化降解活性.机理分析表明,Fe掺杂进ZnO,Fe^(3+)可以形成陷阱捕获e-,导致ZnO的导带下方形成一个Fe掺杂能级,促使缩短了ZnO的带隙,扩... 详细信息

采用水热合成法及煅烧法,制备了不同掺杂量的Fe_(0.02)/Ag_(x)-ZnO复合材料,并考察了各催化剂对RhB光催化降解活性.机理分析表明,Fe掺杂进ZnO,Fe^(3+)可以形成陷阱捕获e-,导致ZnO的导带下方形成一个Fe掺杂能级,促使缩短了ZnO的带隙,扩大了光谱响应范围;Ag的掺入促使部分电子(e^(-))跃迁到Ag单质上,减小了禁带宽度,降低了电子跃迁所需的能量,抑制了e^(-)-h^(+)的复合,Fe_(0.02)/Ag_(x)-ZnO样品的新费米能级低于Fe-ZnO和ZnO的导带能级,导致其界面处的电荷分离;进一步研究Fe_(0.02)/Ag_(x)-ZnO复合材料对染料罗丹明B(Rhodamine B,RhB)的光催化降解性能和循环使用性能.结果表明,Fe_(0.02)/Ag_(x)-ZnO复合材料可作为一种稳定、高效且可循环的光催化剂材料并用于污水处理,拓展了Fe_(0.02)/Ag_(x)-ZnO复合材料的应用.

关键词：电子跃迁费米能级禁带宽带光催化

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Agricultural GMO safety administration in China

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Journal of Integrative Agriculture 2015年第11期14卷 2157-2165页

作者： KOU Jian-ping TANG Qiao-ling ZHANG xian-fa Biosafety Office of Agricultural GMOs Ministry of Agriculture of China (MOA) Biotechnology Research Institute Chinese Academy of Agricultural Sciences

Given the public concern over the safety of genetically modified （GM） technology and products, the article elaborated the safety regulatory and administration on agricultural GMOs in China. China has made a set of laws and regulations of GMO safety management and confirmed competent authorities with clear-cut responsibilities. According to the laws and regulations, GMO products before entering markets have to pass through safety evaluation, get production and processing permission and be labeled correctly. For the importation of GM products, China has set up an import approval system. In addition, China has established technical supportive systems, including safety evaluation specifications, trial specifications and criteria specifications. The existing regulatory system supervises and regulates all activities and work related to agri- cultural GMOs in China.

关键词： GMOs bio-technology safety evaluation labeling information disclosure

A second order isoparametric finite element method for elliptic interface problems

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Applied Mathematics(A Journal of Chinese Universities) 2013年第1期28卷 57-74页

作者： faNG Xu-fa HAN Dan-fu HU xian-liang Department of Mathematics Zhejiang University

A second order isoparametric finite element method （IPFEM） is proposed for elliptic interface problems. It yields better accuracy than some existing second-order methods, when the coefficients or the flux across the immersed curved interface is discontinuous. Based on an initial Cartesian mesh, a mesh optimization strategy is presented by employing curved boundary elements at the interface, and an incomplete quadratic finite element space is constructed on the optimized mesh. It turns out that the number of curved boundary elements is far less than that of the straight one, and the total degree of freedom is almost the same as the uniform Cartesian mesh. Numerical examples with simple and complicated geometrical interfaces demonstrate the efficiency of the proposed method.

关键词： Isoparametric element elliptic problem curved boundary element interface element immersed interface problem.

人工智能文生视频大模型Sora对科技伦理的冲击及应对

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新疆师范大学学报（哲学社会科学版） 2025年第1期46卷 142-148页

作者：曹贤平南昌工程学院马克思主义学院江西南昌330099

Sora的推出是人类社会发展和人工智能进步的标志性事件,凸显出生成式人工智能的强大功能。Sora的爆火离不开规模化数据、先进算法和规模化算力,其内在运行机制紧扣文本输入、文本编码、视频生成和视频输出的基本逻辑,在人类社会具有广... 详细信息

Sora的推出是人类社会发展和人工智能进步的标志性事件,凸显出生成式人工智能的强大功能。Sora的爆火离不开规模化数据、先进算法和规模化算力,其内在运行机制紧扣文本输入、文本编码、视频生成和视频输出的基本逻辑,在人类社会具有广阔应用前景。但Sora在技术更迭和运用过程中可能给科技伦理带来诸如冲击人的主体性地位、导致人们认知的混乱性、冲击伦理规则的适用性、冲击数字隐私伦理并造成数字歧视等风险。因此,要坚持以人为本,运用技术手段增强Sora的数据筛选力度和敏捷治理效度,防止数据泄露和侵犯隐私,进行伦理设计实现科技伦理与时俱进,辅之必要的教育培训,以此提升全民运用人工智能技术的能力。

关键词： Sora 生成式人工智能科技伦理