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Valley-dependent transport in strain engineering graphene heterojunctions

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Chinese Physics B 2022年第7期31卷 509-515页

作者： Fei Wan X R Wang L h Liao J Y Zhang M N Chen G h Zhou Z B Siu Mansoor B.A.Jalil Yuan Li Department of Physics Hangzhou Dianzi UniversityHangzhou 310018China Department of Physics and Key Laboratory for Low-Dimensional Quantum Structures and Manipulation(Ministry of Education) Hunan Normal UniversityChangsha 410081China Computational Nanoelectronics and Nano-device Laboratory Electrical and Computer Engineering DepartmentNational University of SingaporeSingapore 117576Singapore

We study the effect of strain on band structure and valley-dependent transport properties of graphene *** is found that valley-dependent separation of electrons can be achieved by utilizing strain and on-site *** the presence of strain,the values of transmission can be effectively adjusted by changing the strengths of the strain,while the transport angle basically keeps *** an extra on-site energy is simultaneously applied to the central scattering region,not only are the electrons of valleys K and K'separated into two distinct transmission lobes in opposite transverse directions,but the transport angles of two valleys can be significantly ***,one can realize an effective modulation of valley-dependent transport by changing the strength and stretch angle of the strain and on-site energies,which can be exploited for graphene-based valleytronics devices.

关键词： strain engineering valley-dependent separation graphene on-site energy

Fabrication of high quality UV-written fiber bragg gratings

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Chinese Science Bulletin 1997年第5期42卷 377-380页

作者： Chen, GX Jian, SS Ge, h Yang, L Li, X Wang, W Institute of Lightwave Technology Northern Jiaotong University Beijing China National Research Center for Optoelectronics Technology Institute of Semiconductor Chinese Academy of Sciences Beijing China

FIBER gratings have attracted increasing attention since Meltz and coworkers first demon-

关键词： fiber Bragg grating fiber filter fiber photosensitivity.

Transparent conductive SnO_(2)thin films via resonant Ta doping

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Science China Materials 2023年第1期66卷 264-271页

作者： Vedaste Uwihoreye Zhenni Yang Jia-Ye Zhang Yu-Mei Lin Xuan Liang Lu Yang Kelvin h.L.Zhang College of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361005China

Transparent conductive oxide(TCO)thin films are highly desired as electrodes for modern flat-panel displays and solar *** indium-free TCO materials are highly needed,because of the scarcity and the high price of *** on the mechanism of resonant doping,Ta has been identified as an effective dopant for SnO_(2)to achieve highly conductive and transparent *** this work,we fabricated a series of Ta-doped SnO_(2)thin films(Sn_(1-x)Ta_(x)O_(2),x=0.001,0.01,0.02,0.03)with high conductivity and high optical transparency via a low-cost sol-gel spin coating *** Sn_(0.98)Ta_(0.02)O_(2)film achieves the highest electrical conductivity of 855 S cm-1with a carrier concentration of2.3×10^(20)cm^(-3)and high mobility of 23 cm^(2)V^(-1)s^(-1).The films exhibit a very high optical transparency of 89.5%in the visible light ***-resolution X-ray photoemission spectroscopy and optical spectroscopy were combined to gain insights into the electronic structure of the Sn_(1-x)Ta_(x)O_(2)*** optical bandgaps of the films are increased from 3.96 eV for the undoped SnO_(2)to 4.24 eV for the Sn_(0.98)Ta_(0.02)O_(2)film due to the occupation of the bottom of conduction band by free electrons,i.e.,the Burstein-Moss ***,a bandgap shrinkage is also directly observed due to the bandgap renormalization arising from many-body *** double guarantee of transparency and conductivity in Sn_(1-x)Ta_(x)O_(2)films and the low-cost growth method provide a new platform for optoelectronic and solar cell applications.

关键词： transparent conductive oxide sol-gel spin coating Ta-doped SnO_(2) electronic structure

约瑟夫森结AlO_x-Al隧道势垒的实验研究

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物理学报 1997年第1期46卷 22-27页

作者：刘必荣 h.Mantle 安徽大学物理系瑞士邮电科学院

通过Ｘ光电子能谱（ＸＰＳ）、阳极氧化电压谱（ＡＶＳ）和Ｆｉｓｋｅ台阶电压的测量，研究了约瑟夫森结中ＡｌＯｘＡｌ隧道势垒．发现结的隧道势垒最佳沉积Ａｌ层厚度为７ｎｍ，Ａｌ上形成ＡｌＯｘ厚度只取决于氧化条件，与沉积Ａｌ... 详细信息

通过Ｘ光电子能谱（ＸＰＳ）、阳极氧化电压谱（ＡＶＳ）和Ｆｉｓｋｅ台阶电压的测量，研究了约瑟夫森结中ＡｌＯｘＡｌ隧道势垒．发现结的隧道势垒最佳沉积Ａｌ层厚度为７ｎｍ，Ａｌ上形成ＡｌＯｘ厚度只取决于氧化条件，与沉积Ａｌ厚无关，势垒Ａｌ氧化物可能含有一个像ＡｌＯＯＨ态的ＯＨ基团．同时，估算了剩余Ａｌ厚度，证实了结中Ａｌ／Ｎｂ间在４２Ｋ时。

关键词：约瑟夫森结隧道势垒半导体量子论

Comparing the Effectiveness of Coatings on Carbide andCermet Cutting Tool Inserts

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Journal of Materials Science & Technology 1995年第4期11卷 269-275页

作者： K.h. W.Seah M.Rahman and C.h.Lee (Dept. of Mech. & Prod. Eng., National University of Singapore, 10 Kent Ridge Crescent, Singapore 0511 T.N.Goh (Dept. of Ind. & Sys. Eng., National University of Singapore, 10 Kent Ridge Crescent, Singapore 0511) National Univ of Singapore Singapore

A series of metal cutting experiments was performed on a CNC lathe to evaluate the performance of various coatings on different tool substrates. The workpiece material was plain medium carbon steel and the cutting tool materials were carbide and cermet inserts coated with various single as well as multilayer coatings. Machining was done under various cutting conditions of speed and feed-rate, and for various durations of Cutting. The output parameters studied were the cutting forces (axial, radial and tangential), the surface roughness of the workpiece, as well as the tool wear (crater and flank wear). From these results, the performances of the various cutting inserts are evaluated and compared. Results show that cutting forces are significantly lower when using coated cermets than when using coated carbides although different coatings on the same substrate also result in different cutting forces. however, there is less difference in the surface roughness of the finished workpiece for the various coatings and substrates.

关键词： Tool Comparing the Effectiveness of Coatings on Carbide andCermet Cutting Tool Inserts

Palaeozoic Plants from Ninghsia

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地质学报 1945年 227-260+341-343页

作者： h.C.Sze h.h.Lee Geological Survey of China Institute of Geology Academia Sinica

INTRODUCTION The fossil plants forming the subject of this paper were collected ***;and *** of the geological Survey of China in *** collection is fairly large,but unfortunately the specimens are generally

关键词： Palaeozoic Plants from Ninghsia

用面积平衡原理预测伸展断陷盆地中岩层内部应变及亚分辨正断层的方法

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地球科学（中国地质大学学报） 2002年第6期27卷 696-702页

作者：漆家福 Groshong R h Jr 杨桥教育部石油天然气成藏机理重点实验室北京102249 Department of Geological Sciences

大多数地堑和半地堑是由深度近水平的拆离正断层控制的 .根据面积平衡原理 ,这些伸展断陷盆地岩层的区域基准面至拆离断层面高度 (h)与其损失面积 (S)呈线性比例 .拆离断层之上的盆地基底岩层的水平伸展量相同 ,因此 ,用“S -h图解法”... 详细信息

大多数地堑和半地堑是由深度近水平的拆离正断层控制的 .根据面积平衡原理 ,这些伸展断陷盆地岩层的区域基准面至拆离断层面高度 (h)与其损失面积 (S)呈线性比例 .拆离断层之上的盆地基底岩层的水平伸展量相同 ,因此 ,用“S -h图解法”可以确定拆离断层深度 ,并能在此基础上计算出岩层的总水平伸展量 .伸展盆地中的总水平伸展量主要是由不同尺度的正断层的水平离距体现出来的 .可观测解释的断层的水平位移可以通过测量盆地宽度、岩层长度等直接得到 .用剖面面积平衡方法可计算出盆地各岩层的平行岩层面的应变 ,其中相当部分是由在观测尺度上不能直接解释出来的“亚分辨正断层”的小尺度位移造成的 .因此 ,在分析伸展断陷盆地的构造样式、岩层力学性质基础上 ,有可能对计算得到的平行岩层的伸展应变进行合理评估 ,进而可以定量地预测“亚分辨正断层”的密度和可能的分布部位 .

关键词：伸展断陷盆地岩层面积平衡伸展应变亚分辨断层地堑半地堑 S-h图解

Catalytic feasibility of Ce-doped LaCoO_(3) systems for chlorobenzene oxidation:An analysis of synthesis method

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Journal of Rare Earths 2022年第6期40卷 897-905,I0002页

作者： héctor Acosta Pérez Carlos A.López Luis E.Cadús Fabiola N.Agüero Chemical Technology Research Institute(INTEQUI) UNSL-CONICETFaculty of Biochemical Chemistry and Pharmacy(UNSL)Almirante Brown 14555700San LuisArgentina

A family of Ce-doped LaCoO_(3) perovskites are presented as possible catalysts for Cl-VOCs *** materials with different contents of Ce were obtained through the citrate and the reactive grinding *** insertion of Ce in the original perovskite structure favours the presence of Co^(2+)/Co^(3+) and Ce^(3+)/Ce^(4+) redox pairs and a higher content of oxygen vacancies that enhances the catalytic performance in chlorobenzene combustion based on differential kinetics *** family obtained by the grinding method presents a performance as high as that synthesized by citrate ***,the reactive grinding is a feasible green chemistry alternative to obtain a catalyst with the same performance as that obtained from traditional ***,the stability of samples was evaluated under total combustion reaction conditions showing an excellent activity during 45 h time on stream.

关键词： Cl-VOCs Perovskites Chlorobenzene Cerium Cobalt Rare earths

Kernel-based Consensus Clustering for Ontology-embedded Document Repository of Power Substations

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CSEE Journal of Power and Energy Systems 2017年第2期3卷 212-221页

作者： Long Yan Wenhu Tang Q.h.Wu Jeremy Simon Smith Department of Electrical Engineering and Electronic The University of LiverpoolLiverpoolL693GJU.K. School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China

This paper presents a novel consensus clustering(CC)approach for a document repository concerning power substations(PSD)and contributes to the intangible asset management of power systems.A domain ontology model,i.e.,substation ontology(SONT),is applied to modify the traditional vector space model(VSM)for document representation,which is concerned with the semantic relationship between terms.A new document representation is generated using a term mutual information matrix with the aid of *** addition,compared with two other novel CC algorithms,i.e.,non-negative matrix factorisation-based CC(NNMF-CC)and information theory-based CC(INT-CC),weighted partition via kernel-based CC algorithm(WPK-CC)is utilised to solve the CC issue for ***,genetic algorithms(GA)were applied to WPK-CC for PSD,as there are limitations in the original WPK-CC for document ***,selected mechanisms in each GA’s procedure are compared and improved,resulting in comprehensive parameter settings for the PSD *** simulation studies have been designed,in which the results are evaluated by purity validation method and show that the SONT-based document representation and improved WPK-CC,via modified GA,significantly improve the performance of the PSD CC.

关键词： power system asset management document clustering consensus clustering ontology kernel method GA