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黑磷/黑砷异质结纳米器件热电性质应力调控研究

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原子与分子物理学报 2025年第1期42卷 69-74页

作者：戎杙邱乙峰张蓓新疆大学物理科学与技术学院乌鲁木齐830046

探索新型高性能低维热电纳米材料已成为国家重大发展策略.论文采用密度泛函理论结合非平衡态格林函数方法研究了由黑磷、黑砷纳米带构建异质结构在2%、4%、6%和8%四种拉伸应变作用下热电性能调控机理.研究结果表明,6%拉伸应变较其他情形... 详细信息

探索新型高性能低维热电纳米材料已成为国家重大发展策略.论文采用密度泛函理论结合非平衡态格林函数方法研究了由黑磷、黑砷纳米带构建异质结构在2%、4%、6%和8%四种拉伸应变作用下热电性能调控机理.研究结果表明,6%拉伸应变较其他情形,能够更有效抑制声子输运行为;与此同时,拉伸应变对于器件的电子输运的调控效果并不明显.在费米能附近,黑磷/黑砷异质结纳米器件在6%拉伸应变调控下热电优值达到最大值2.31.

关键词：黑磷黑砷异质结应力热电性质

THE HOLDER CONTINUITY OF THE LYAPUNOV EXPONENT FOR A QUASI-PERIODIC SZEGO COCYCLE

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Acta Mathematica Scientia 2024年第6期44卷 2099-2110页

作者： bei zhang School of Mathematical Sciences Ocean University of ChinaQingdao 266100China

In this paper,I consider the Hölder continuity of the Lyapunov exponent for a quasi-periodic Szegö cocycle with weak Liouville frequency.I extend the existing results about the regularity of the Lyapunov exponent from... 详细信息

关键词： Szegöcocycle Lyapunov exponents Holder continuity orthogonal polynomials

Assembly of versatile fluorine-containing structures via N-heterocyclic carbene organocatalysis

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Science China Chemistry 2022年第9期65卷 1691-1703页

作者： bei zhang Jian Wang School of Pharmaceutical Sciences Tsinghua UniversityBeijing 100084China College of Chemistry and Materials Science Anhui Normal UniversityWuhu 241000China

Owing to the unique properties of fluorine-containing moieties in the pharmaceuticals,agrochemicals and materials,several synthetic efforts(i.e.,enzymatic resolution,transition-metal catalysis,and organocatalysis)have been frequently made to fabricate these fluorinated *** powerful organic catalysts,N-heterocyclic carbenes can activate carbonyl group and realize the chiral intervention of multiple sites near the carbonyl group,and have an irreplaceable power to construct fluorine-containing ***,NHC-related reviews focused on the versatile synthesis of fluorine-containing fragments are absolutely rare to this *** mini-review highlights the invention of inserting fluorine atom or assembling fluorine-containing fragments via NHC *** summarizing the achievements in this field,we are eager to provide enlightening clues for further developments.

关键词： N-heterocyclic carbene fluorination electrophilic trifluoromethylation radical perfluoroalkylation annulation

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Recent progress in carbene-catalyzed fluoroalkylation

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Science China Chemistry 2024年第8期67卷 2448-2460页

作者： bei zhang Xuan zhang Jian Wang Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044China School of Pharmaceutical Sciences Tsinghua UniversityBeijing 100084China

The fluoroalkyl fragment plays a vital role in various fields such as pharmaceuticals and materials science, and has a significant impact on human life not only on the present but also in the future. The insertion of fluoroalkyl groups into the chemical skeletons can cause considerable alternations in the chemical, physical and biological properties of molecules, which has attracted numerous scientists from different fields. This review focuses on N-heterocyclic carbene(NHC)-catalyzed fluoroalkylation reactions, providing a detailed analysis and summary of the achievements in the past two decades. Many successful examples clearly indicate that NHCs can catalyze the tranformation of fluoroalkylation reagents with various electronic characteristics, whether electrophilic, nucleophilic, or radical precursors. Herein, the fluoroalkylation reactions are classified based on different catalytic modes of NHCs: Lewis base catalysis, Umploung catalysis, radical catalysis and others. Meanwhile, by refining and systematically studying the contribution of NHC catalysis in fluoroalkylation reactions, this review is expected to provide valuable insights and enlightenment for related fields.

关键词： N-heterocyclic carbene fluoroalkylation radical catalysis

Study on first caving fracture mechanism of overlying roof rock in steep thick coal seam

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International Journal of Mining Science and Technology 2015年第1期25卷 133-138页

作者： zhang bei Cao Shenggen State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology Shanxi Provincial Guoxin Energy Development Group Co. Ltd.

Based on the elastic plate theory, a mechanical model of thin plate for the first caving of overlying roof rock in steep mining face was established. The analytical solution of the deflection and stress distribution of roof rocks was obtained. According to the specific geological conditions of the 5-103 panel in Shanxi,the failure of roof rocks and the influence of seam dip on it during the exploitation were theoretically investigated. Meanwhile, the first caving characteristics of the overlying rock in the steep coal seam were investigated based on its stress contour. The results show that the dip angle has a distinct influence on the caving interval and the first caving interval for the 5-103 panel is 37 m in theory. Finally, a systematic monitoring on the behavior of rock pressures was conducted. The measured results agree well with the theoretical prediction, which provides a good reference for practical steep coal seam mining.

关键词： SteepMining fieldInitial fracture intervalThin plate theoryCoal pressure monitoring

Crushing Behaviors of Frac tai Hexagonal Tubular Structures: Experiments and Plastic Analysis

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Acta Mechanica Solida Sinica 2019年第6期32卷 713-724页

作者： Weiwei Li bei zhang Hualin Fan Research Center of Lightweight Structures and Intelligent Manufacturing State Key Laboratory of Mechanics and Control of Mechanical StructuresNanjing University of Aeronautics and AstronauticsNanjing 210016China State Key Laboratory for Disaster Prevention&Mitigation of Explosion&Impact PLA Army Engineering UniversityNanjing 210007China Department of Civil Engineering Nanyang Institute of TechnologyNanyang 473004China Research Institute for National Defense Engineering of Academy of Military Science PLA Luoyang 471023China

Fractal tubular structures(FTSs)can greatly increase the anti-crushing and energy absorption capacity of the *** reveal this mechanism,fractal hexagonal tubes(FHTs)with self-similar fractal structure were designed and *** experiments were carried out to verify the crushing modes of structures with different scale *** with the single-cell structure,FHTs have much greater mean crushing force(MCF).According to the experiments and the numerical simulations,when the side length of the second-order hexagon is 0.3 times of the length of the first-order primary hexagon,the FTS has the greatest peak force(PF)and MCF as well as the most excellent energy-absorbing *** folding styles were revealed by the experiments and the numerical simulation when changing the scale factor,including the overall folding mode,the local foaling mode and the hybrid folding *** plastic models were built,which consistently predicted the MCF.

关键词： Fractal structure Crushing Energy absorption Plastic analysis

Benzothiadiazole-based materials for organic solar cells

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Chinese Chemical Letters 2024年第1期35卷 3-15页

作者： Qiang bei bei zhang Kaifeng Wang Shiming zhang Guichuan Xing Clément Cabanetos Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)Nanjing Tech UniversityNanjing 211816China Jiangsu Seenbom Flexible Electronics Institute Co. Ltd.Nanjing 210043China Institute of Applied Physics and Materials Engineering University of MacaoMacao SAR 999078China University of Angers Angers 49045France Building Blocks for Future Electronics Laboratory(2BFUEL) IRL2002CNRS-Yonsei UniversitySeoul 03722Republic of Korea

The past few years have witnessed power conversion efficiency(PCE)of organic solar cells(OSCs)skyrocketing to the value of 20%due to the outstanding advantages of organic photoactive *** latter,which consist of donor and acceptor materials,indeed play important roles in OSCs,and particularly one building block has attracted considerable research attention,namely benzothiadiazole(BT).The diversity of OSCs based on the BT structure have indeed sprung up,and the progressive increase in PCE values is more than just eye-catching since it heralds a renewal and bright future of *** review analyzes significant studies that have led to these remarkable progresses and focuses on the most effective BT small-molecules and BT polymers for OSC reported in the last *** pivotal structure-property relationships,donor-acceptor matching criteria,and morphology control approaches are gathered and discussed in this ***,we summarize the remaining challenges and offer a personal perspective on the future advance and improvement of OSCs.

关键词： Organic solar cells Benzothiadiazole Donor Acceptor Polymer Non-fullerene acceptors

A new dicaffeoyl quinic acid from Nannoglottis ravida

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Chinese Chemical Letters 2010年第2期21卷 203-205页

作者： Jiang, Jing zhang, bei bei Liao, Zhi Xin Southeast Univ Sch Chem & Chem Engn Dept Pharmaceut Engn Nanjing 211189 Peoples R China

A new dicaffeoyl quinic acid,nannoglottisin A,has been isolated from an endemic plant of Nannoglottis ravida,and the structure of the compound was identified by means of spectroscopic analysis.

关键词： Quinic acid Nannoglottis ravida Endemic plant

Crown-Like Baffle System against Rock Avalanches:Energy Dissipation Mechanism and Numerical Verification

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Journal of Earth Science 2023年第2期34卷 304-315页

作者： Yu Huang Hao Shi bei zhang Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering of the Ministry of Education Tongji UniversityShanghai 200092China

In mountainous areas,rock avalanches swarm downslope leading to large impact forces on *** systems are usually set up in torrent channels to dissipate the flow energy and reduce the destructive *** this paper,a crown-like baffle system is proposed to better dissipate the flow *** energy dissipation mechanism of this system was investigated based on *** results reveal more than 90%of the kinetic energy of the granular flow was dissipated by particleparticle *** effects,the impedance effect and the deflection effect,were *** influence of these effects leads to the formation and growth of cushions behind the baffles,and these cushions enhance the particle-particle *** crown-like baffle systems were compared with a conventional baffle system based on the typical avalanche *** results reveal the cumulative residual kinetic energy of the crown-like baffle system with square baffles decreased by 18.75%with the same concrete consumption as the conventional baffle *** the crown-like baffle system with triangular baffles,the cumulative residual kinetic energy decreased by 6.22%with 83.94%of the concrete consumption of the conventional baffle ***,the proposed baffle system is more cost-effective compared with the conventional baffle system.

关键词： rock avalanches new baffle system energy dissipation discrete element method engineering geology