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National Science Review 2018年第1期5卷 59-69页

作者： Ehsan Nasr Esfahani Feiyue Ma Shanyu Wang Yun Ou jihui yang Jiangyu Li Department of Mechanical Engineering University of Washington Shenzhen Key Laboratory of Nanobiomechanics Shenzhen Institutes of Advanced TechnologyChinese Academy of Sciences Department of Materials Science andEngineering University of Washington

In the last two decades, a nano structuring paradigm has been successfully applied in a wide range of thermoelectric materials, resulting in significant reduction in thermal conductivity and superior thermoelectric performance. These advances, however, have been accomplished without directly investigating the local thermoelectric properties, even though local electric current can be mapped with high spatial resolution. In fact, there still lacks an effective method that links the macroscopic thermoelectric performance to the local micro structures and properties. Here, we show that local thermal conductivity can be mapped quantitatively with good accuracy, nanometer resolution and one-to-one correspondence to the micro structure using a three-phase skutterudite as a model system. Scanning thermal microscopy combined with finite element simulations demonstrate close correlation between sample conductivity and probe resistance,enabling us to distinguish thermal conductivities spanning orders of magnitude, yet resolving thermal variation across a phase interface with small contrast. The technique thus provides a powerful tool to correlate local thermal conductivities, micro structures and macroscopic properties for nano structured materials in general and nano structured thermo electrics in particular.

关键词： thermal conductivity scanning thermal microscopy thermoelectric materials nanoscale heat transfer thermal imaging

Defect-mediated Rashba engineering for optimizing electrical transport in thermoelectric BiTeI

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npj Computational Materials 2020年第1期6卷 774-780页

作者： Xin Li Ye Sheng Lihua Wu Shunbo Hu Jiong yang David J.Singh jihui yang Wenqing Zhang Materials Genome Institute Shanghai University99 Shangda Road200444 ShanghaiChina Materials Science and Engineering Department University of WashingtonSeattleWA 98195USA Department of Physics and Astronomy and Department of Chemistry University of MissouriColumbiaMO 65211USA Department of Physics and Shenzhen Institute for Quantum Science&Technology Southern University of Science and Technology518055 ShenzhenGuangdongChina Guangdong Provincial Key Laboratory of Computational Science and Material Design and Shenzhen Key Laboratory of Advanced Quantum Functional Materials and DevicesSouthern University of Science and Technology518055 ShenzhenGuangdongChina

The Rashba effect plays a vital role in electronic structures and related functional *** strength of the Rashba effect can be measured by the Rashba parameter α_(R);it is desirable to manipulate α_(R) to control the functional *** current work illustrates how α_(R) can be systematically tuned by doping,taking BiTeI as an example.

关键词： properties Rashba doping

On the tuning of electrical and thermal transport in thermoelectrics: an integrated theory–experiment perspective

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npj Computational Materials 2016年第1期2卷 216-232页

作者： Jiong yang Lili Xi Wujie Qiu Lihua Wu Xun Shi Lidong Chen jihui yang Wenqing Zhang Ctirad Uher David J Singh Materials Genome Institute Shanghai UniversityShanghaiChina State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghaiChina Department of Physics East China Normal UniversityShanghaiChina Material Science and Engineering Department University of WashingtonSeattleWAUSA Department of Physics University of MichiganAnn ArborMIUSA Department of Physics and Astronomy University of MissouriColumbiaMOUSA

During the last two decades,we have witnessed great progress in research on *** are two primary *** is the fundamental understanding of electrical and thermal transport,enabled by the interplay of theory and experiment;the other is the substantial enhancement of the performance of various thermoelectric materials,through synergistic optimisation of those intercorrelated transport *** we review some of the successful strategies for tuning electrical and thermal *** electrical transport,we start from the classical but still very active strategy of tuning band degeneracy(or band convergence),then discuss the engineering of carrier scattering,and finally address the concept of conduction channels and conductive networks that emerge in complex thermoelectric *** thermal transport,we summarise the approaches for studying thermal transport based on phonon–phonon interactions valid for conventional solids,as well as some quantitative efforts for *** also discuss the thermal transport in complex materials with chemical-bond hierarchy,in which a portion of the atoms(or subunits)are weakly bonded to the rest of the structure,leading to an intrinsic manifestation of part-crystalline part-liquid state at elevated *** this review,we provide a summary of achievements made in recent studies of thermoelectric transport properties,and demonstrate how they have led to improvements in thermoelectric performance by the integration of modern theory and experiment,and point out some challenges and possible directions.

关键词： electrical thermal theory

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一类灰正项几何规划的解法

辽宁工程技术大学学报（自然科学版） 2010年第5期29卷 937-940页

作者：杨吉会沈阳炮兵学院基础教研室辽宁沈阳11016

为了讨论一类系数和指数都是区间灰数的正项几何规划的求解方法,通过对区间灰数适当的白化后将灰正项几何规划转化成通常的正项几何规划,利用正项几何规划的对偶算法求出最优解。以区间灰数的形式给出了该类灰正项几何规划的最优解。丰... 详细信息

为了讨论一类系数和指数都是区间灰数的正项几何规划的求解方法,通过对区间灰数适当的白化后将灰正项几何规划转化成通常的正项几何规划,利用正项几何规划的对偶算法求出最优解。以区间灰数的形式给出了该类灰正项几何规划的最优解。丰富了正项几何规划的研究内容,扩展了正项几何规划的应用范围。

关键词：区间灰数灰正项几何规划对偶规划最优解

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Universal Machine Learning Kohn–Sham Hamiltonian for Materials

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Chinese Physics Letters 2024年第7期41卷 95-110页

作者：钟阳于宏宇杨吉辉郭星宇向红军龚新高 Key Laboratory of Computational Physical Sciences(Ministry of Education) Institute of Computational Physical SciencesState Key Laboratory of Surface Physicsand Department of PhysicsFudan UniversityShanghai 200433China Shanghai Qi Zhi Institute Shanghai 200030China

While density functional theory(DFT)serves as a prevalent computational approach in electronic structure calculations,its computational demands and scalability limitations ***,leveraging neural networks to parameterize the Kohn-Sham DFT Hamiltonian has emerged as a promising avenue for accelerating electronic structure *** advancements,challenges such as the necessity for computing extensive DFT training data to explore each new system and the complexity of establishing accurate machine learning models for multi-elemental materials still *** these hurdles,this study introduces a universal electronic Hamiltonian model trained on Hamiltonian matrices obtained from first-principles DFT calculations of nearly all crystal structures on the Materials *** demonstrate its generality in predicting electronic structures across the whole periodic table,including complex multi-elemental systems,solid-state electrolytes,Moir´e twisted bilayer heterostructure,and metal-organic ***,we utilize the universal model to conduct high-throughput calculations of electronic structures for crystals in GNoME datasets,identifying 3940 crystals with direct band gaps and 5109 crystals with flat *** offering a reliable efficient framework for computing electronic properties,this universal Hamiltonian model lays the groundwork for advancements in diverse fields,such as easily providing a huge data set of electronic structures and also making the materials design across the whole periodic table possible.

关键词： Hamiltonian utilize twisted

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Magnetic Resonance Spectroscopy Study on Basal Ganglia and Cerebellum in Patients with Insomnia Disorder

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Magnetic Resonance Spectroscopy Study on Basal Ganglia and C...

多国规范平屋盖围护结构外表面设计风压对比研究

中国睡眠研究会第九届学术年会

作者： Qiaoting Huang jihui yang Yaohui Han Jiwu Liao Ping Ma Jiyang Pan Department of Psychiatry The First Affiliated Hospital Jinan University

＜正＞Objectives:To studythe correlation between N-acetylaspartate（NAA）,choline-containing compound（Cho）,myo-inositol（ml）and creatine（Cr）metabolism of basal ganglia and cerebellum and hyperarousal in patients with insomnia disorder,and explore the role of basal ganglia and cerebellummetabolic disturbancein thepathogenesis of insomnia ***:A total of 23 non-medicated patients who met the DSM-5 diagnostic criteria for insomnia

关键词： Insomnia Disorder Magnetic Resonance Spectroscopy N-acetylaspartate Hyperarousal

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建筑结构学报 2017年第3期38卷 127-133页

作者：邢佶慧李丹煜杨庆山田玉基北京交通大学土木建筑工程学院北京100044 北京交通大学结构风工程与城市风环境北京市重点实验室北京100044

对比分析了中国GB 50009—2012、德国DIN 1055-4、美国ASCE/SEI 7-10、日本AIJ-2004、欧洲BS EN 1991-1-4:2005、加拿大NBC-2005、澳大利亚/新西兰AS/NZS 1170.2:2011、英国BS 6399-2:1997等规范中关于平屋盖围护结构外表面设计风压的有关规定。为便于比较,将各国规范风荷载标准值统一换算为外表面设计风压系数与基本风压乘积的形式。并且将外表面设计风压统一换算为与时距10min、重现期50 a的基本风速相对应的值。针对外表面设计风压相关因素,对风向、风压分区、面积折减、建筑尺寸等进行了对比研究。最后,结合平屋盖风洞试验,探讨了外表面设计风压的具体取值建议。研究表明:平屋盖围护结构外表面设计风压的确定,建议考虑360°全风向;对屋盖边缘应进行风压分区,角部也应进行单独的风压分区;屋盖表面不同位置建议采用不同的面积折减公式;针对不同高度或宽高比建筑给定不同的外表面设计风压建议取值。

关键词：围护结构平屋盖外表面设计风压系数风荷载

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