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When thermoelectric materials come across with magnetism

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Rare Metals 2021年第4期40卷 752-766页

作者： chen-chen zhao Chong Xiao Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China Institute of Energy Hefei Comprehensive National Science CenterHefei 230031China

Nowadays,thermoelectric materials have attracted a lot of attention as they can directly convert heat into electricity and vice ***,while strenuous efforts have been made,those conventional strategies are still inevitably going to meet their performance optimization *** this reason,brand new strategies are badly needed to achieve further ***,the roles played by magnetism in recent advances of thermoelectric optimization are ***,magnetic thermoelectric materials can just be treated like other normal materials because the use of universal optimization strategies can still get good ***,it is not a situation which is all or nothing and the tactics of using magnetism for thermoelectric optimization can coexist with other ***,through magnetic doping,we can introduce and adjust magnetism in materials for further *** provides more possibilities in thermoelectric optimization as it can directly influence the spin states in ***,in the form of magnetic secondphase nanoclusters,magnetism can be introduced to thermoelectric materials to conquer the dilemma that the solid solubility of many magnetic ions in thermoelectric materials is too low to have any significant effect on thermoelectric ***,when exposed to an external magnetic field,topological materials can rely on its unique band structures to optimize.

关键词： Thermoelectricity Magnetic thermoelectric materials Magnetism Magnetic doping Magnetic second phase

Motion Characteristics Analysis of a Novel Spherical Two-degree-of-freedom Parallel Mechanism

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Chinese Journal of Mechanical Engineering 2022年第2期35卷 91-99页

作者： Ziming chen Xuechan chen Min Gao chen zhao Kun zhao Yanwen Li School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan UniversityQinhuangdao 066004HebeiChina

Current research on spherical parallel mechanisms(SPMs)mainly focus on surgical robots,exoskeleton robots,entertainment equipment,and other ***,compared with the SPM,the structure types and research contents of the SPM are not abundant *** this paper,a novel two-degree-of-freedom(2DOF)SPM with symmetrical structure is proposed and ***,the models of forward kinematics and inverse kinematics are established based on D-H parameters,and the Jacobian matrix of the mechanism is obtained and ***,the workspace of the mechanism is obtained according to inverse kinematics and link interference ***,rotational characteristics analysis shows that the end effector can achieve continuous rotation about an axis located in the mid-plane and passing through the rotation center of the ***,the rotational characteristics of the mechanism are proved,and motion planning is carried out.A numerical example is given to verify the kinematics analysis and motion ***,some variant mechanisms can be *** work lays the foundation for the motion control and practical application of this 2DOF SPM.

关键词： Spherical parallel mechanism 2DOF Workspace Equivalent rotation

Spectral-spatial classification for hyperspectral imagery: a novel combination method based on affinity scoring

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Science China(Information Sciences) 2016年第10期59卷 181-193页

作者： zhao chen Bin WANG State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Key Laboratory for Information Science of Electromagnetic Waves (Ministry of Education) Fudan University Research Center of Smart Networks and Systems School of Information Science and Technology Fudan University

Recently, a general framework for spectral-spatial classification has caught the attention of the hyperspectral imagery(HSI) society. It consists of three parts: classification, segmentation and combination of the former results to make a refined labeled map. Seeing the potentials of the last part, we derive a novel combination rule based on affinity scoring(CRAS). The core of the system is affinity score(AS), which is derived from fuzzy logic. Every AS measures the degree, i.e., the affinity, by which a pixel belongs to a class. The score is essentially decided by three factors: local spatial consistency, spectral similarity, and prior knowledge. The method is compatible with basic classification and segmentation tools, thus saving the trouble of designing complex techniques for the other parts in the framework. Experimental results show that CRAS excels several basic techniques as well as various state-of-the-art methods in the area of spectral-spatial classification.

关键词： hyperspectral imagery spectral-spatial classification affinity score local spatial consistency fuzzy superpixel

鲁西七星台地区韧性剪切带变形特征及样式:对华北克拉通东部新太古代演化的构造约束

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岩石学报 2025年第1期41卷 237-259页

作者：张书慧张健赵辰苗亚洲刘晓光陈国楷中山大学地球科学与工程学院珠海519000 香港大学地球科学系中国香港中国地质调查局沈阳地质调查中心沈阳110034 山东科技大学地球科学与工程学院青岛266590

鲁西地区是华北克拉通东部陆块的重要组成部分,整体呈NW-SE向带状展布,保留有完整的新太古代地质记录和丰富的新太古代构造样式,对深入研究华北克拉通新太古代构造演化历史具有重要意义。过去的研究主要集中于地球化学、年代学、变质岩... 详细信息

鲁西地区是华北克拉通东部陆块的重要组成部分,整体呈NW-SE向带状展布,保留有完整的新太古代地质记录和丰富的新太古代构造样式,对深入研究华北克拉通新太古代构造演化历史具有重要意义。过去的研究主要集中于地球化学、年代学、变质岩石学等方面,但在构造地质学方面缺乏详细的证据制约。七星台地区位于鲁西西北部,新太古代不同岩性均有出露,保留丰富新太古代时期构造,是研究鲁西地壳形成与演化的经典地区。因此,本文选择在该地区进行了详细的野外构造解析、显微构造分析以及有限应变测量和地质年代学研究。详细野外填图揭示七星台韧性剪切带整体呈NW-SE向展布,剪切带内面理产状近直立,并且发育近水平矿物拉伸线理,而剪切运动学标志不发育。两条代表性构造剖面表明,在二长花岗岩体西侧与新太古代晚期TTG岩石构造接触区域,二长花岗岩为S-L构造岩发育糜棱面理,向东侧变形程度逐渐降低且最终变为块状构造。两条剖面中岩石分布及变形特征相似,不同变形程度的岩石间无明显界限,表明该地区带状分布的近直立岩石面理可能为水平向挤压所致。镜下显微特征也显示变形强度自西向东逐渐减弱的相似趋势,在变形二长花岗岩中普遍存在由强烈拉长的石英颗粒形成的多晶条带,矿物变形行为表明变形温度约450~550℃。利用三种不同方法获得的岩石有限应变测量结果和Flinn图解表明岩石应变类型为压扁型应变。应变强度分布图也显示岩石应变强度中间最强,向东远离构造接触带则呈逐渐降低趋势。LA-ICP-MS锆石U-Pb定年结果显示七星台二长花岗岩形成时代为~2525Ma,结合前人研究,认为鲁西七星台地区变形时代约为2525~2500Ma。综上所述,鲁西地区在新太古代晚期经历了近NE-SW向水平压扁应变和近NW-SE向水平拉伸应变,指示新太古代晚期水平向构造挤压体制在华北克拉通东部陆块可能已经存在。同时,鲁西线性带并不具备典型的俯冲-碰撞造山带变形特征,如复杂的构造应力场变化、大型逆冲推覆构造以及高级变质作用等。这可能与其所处的特殊构造位置有关,如远离俯冲带的陆内应变集中区,但俯冲带的确切位置则需要未来更多详细工作来综合确定。

关键词：新太古代晚期七星台韧性剪切带二长花岗岩有限应变测量鲁西

Composite quantile regression estimation for P-GARCH processes

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Science China Mathematics 2016年第5期59卷 977-998页

作者： zhao Biao chen zhao TAO GuiPing chen Min Department of Statistics and Finance University of Science and Technology of China Department of Statistics Pennsylvnia State University School of Statistics Capital University of Economics and Business Academy of Mathematics and Systems Science Chinese Academy of Sciences

We consider the periodic generalized autoregressive conditional heteroskedasticity(P-GARCH) process and propose a robust estimator by composite quantile regression. We study some useful properties about the P-GARCH model. Under some mild conditions, we establish the asymptotic results of proposed *** Monte Carlo simulation is presented to assess the performance of proposed estimator. Numerical study results show that our proposed estimation outperforms other existing methods for heavy tailed *** proposed methodology is also illustrated by Va R on stock price data.

关键词： composite quantile regression periodic GARCH process strictly periodic stationarity strong consistency asymptotic normality

Trusted Attestation Architecture on an Infrastructure-as-a-Service

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Tsinghua Science and Technology 2017年第5期22卷 469-477页

作者： Xin Jin Xingshu chen cheng zhao Dandan zhao the College of Computer Science Sichuan University

Trusted attestation is the main obstruction preventing large-scale promotion of cloud computing. How to extend a trusted relationship from a single physical node to an Infrastructure-as-a-Service （laaS） platform is a problem that must be solved. The laaS platform provides the Virtual Machine （VM）, and the Trusted VM, equipped with a virtual Trusted Platform Module （vTPM）, is the foundation of the trusted laaS platform. We propose a multi-dimensional trusted attestation architecture that can collect and verify trusted attestation information from the computing nodes, and manage the information centrally on a cloud management platform. The architecture verifies the laaS＇s trusted attestation by apprising the VM, Hypervisor, and host Operating System＇s （OS） trusted status. The theory and the technology roadmap were introduced, and the key technologies were analyzed. The key technologies include dynamic measurement of the Hypervisor at the process level, the protection of vTPM instances, the reinforcement of Hypervisor security, and the verification of the laaS trusted attestation. A prototype was deployed to verify the feasibility of the system. The advantages of the prototype system were compared with the Open CIT （Intel Cloud attestation solution）. A performance analysis experiment was performed on computing nodes and the results show that the performance loss is within an acceptable range.

关键词： dynamic measurement trusted cloud vTPM trusted attestation

原子力显微镜观察体外纯化蛋白分子的表面结构

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中国药理学通报 2025年第1期41卷 193-199页

作者：陈昭颖方骁枫刘丹彦陈梦琴凌夕赵洁旻魏伟吴育晶安徽医科大学临床药理研究所抗炎免疫药物教育部重点实验室安徽合肥230032 安徽医科大学第二临床医学院安徽合肥230022

目的以课题组纯化获得的蛋白样本为观察对象,对比原子力显微镜(atomic force microscope,AFM)及扫描电子显微镜(scanning electron microscope,SEM)的观察结果,并总结AFM观察生物大分子的主要问题和解决方法。方法将蛋白样本使用PBS稀释... 详细信息

目的以课题组纯化获得的蛋白样本为观察对象,对比原子力显微镜(atomic force microscope,AFM)及扫描电子显微镜(scanning electron microscope,SEM)的观察结果,并总结AFM观察生物大分子的主要问题和解决方法。方法将蛋白样本使用PBS稀释至15 nmol·L^(-1),分别固定于载玻片、硅片和云母片上烘干,制成固相观察样本,SEM样本在观察前镀铂,使用AFM及SEM观察蛋白质表面结构,计算样本高度,对比结果差异。结果带正电的蛋白样本在观察时由于AFM探针的斥力会向右偏移;云母片能很好地消除蛋白正电荷从而避免样本移动;PBS能为蛋白样本提供良好的稳定环境,但PBS盐结晶会干扰探针运行和成像清晰度;SEM样本需要镀铂后观察,无法达到AFM的精度。结论使用AFM和SEM均可在体外环境直接观察蛋白质结构,AFM能提供更高精度的观察结果;在蛋白样本稳定性允许的情况下首选超纯水为溶剂载体,乙醇等挥发性液体也可作为溶剂载体,AFM的应用可为药理学生物大分子互作研究提供一新途径。

关键词：原子力显微镜扫描电子显微镜受体结构蛋白质体外结构超微结构云母载体

Almost perfect sequences based on cyclic difference sets

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Journal of Systems Engineering and Electronics 2007年第1期18卷 155-159页

作者： chen Gang zhao Zhengyu Ionosphere Lab Wuhan Univ. Wuhan 430070 E R. China

The perfect sequences are so ideal that all out-of-phase autocorrelation coefficients are zero, and if the sequences are used as the coding modulating signal for the phase-modulated radar, there will be no interference of side lobes theoretically. However, it has been proved that there are no binary perfect sequences of period 4 〈 n ≤ 12100. Hence, the almost perfect sequences with all out-of-phase autocorrelation coefficients as zero except one are of great practice in engineering. Currently, the cyclic difference set is one of most effective tools to analyze the binary sequences with perfect periodic autocorrelation function. In this article, two characteristic formulas corresponding to the autocorrelation and symmetric structure of almost perfect sequences are calculated respectively. All almost perfect sequences with period n, which is a multiple of 4, can be figured out by the two formulas. Several almost perfect sequences with different periods have been hunted by the program based on the two formulas and then applied to the simulation program and practical application for ionospheric sounding.

关键词： Perfect sequence Almost perfect sequence Cyclic difference sets Autocorrelation coefficients Side lobes Ionospheric sounding

The genomic stability of induced pluripotent stem cells

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Protein & Cell 2012年第4期3卷 271-277页

作者： zhao chen Tongbiao zhao Yang Xu Division of Biological Sciences University of CaliforniaSan DiegoLa JollaCA 92093-0322USA

With their capability to undergo unlimited self-renewal and to differentiate into all cell types in the body,in-duced pluripotent stem cells(iPSCs),reprogrammed from somatic cells of human patients with defined fac-tors,hold promise for regenerative medicine because they can provide a renewable source of autologous cells for cell therapy without the concern for immune *** addition,iPSCs provide a unique opportu-nity to model human diseases with complex genetic traits,and a panel of human diseases have been suc-cessfully modeled in vitro by patient-specific *** these progresses,recent studies have raised the concern for genetic and epigenetic abnormalities of iPSCs that could contribute to the immunogenicity of some cells differentiated from *** oncogenic potential of iPSCs is further underscored by the find-ings that the critical tumor suppressor p53,known as the guardian of the genome,suppresses induced ***,the clinic application of iPSCs will require the optimization of the reprogramming technology to minimize the genetic and epigenetic ab-normalities associated with induced pluripotency.

关键词： induced pluripotent stem cells reprogram-ming genetic and epigenetic abnormalities