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In-Situ SRPES Study on the Band Alignment of (0001)CdS/CdTe Heterojunction

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Chinese Physics Letters 2012年第5期29卷 201-204页

作者： GAO jun-Ning JIE Wan-Qi YUAN Yan-Yan ZHA Gang-Qiang XU Ling-Yan WU Heng WANG Ya-Bin YU Hui zhu jun-fa State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072 National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029

The band alignment of a (0001)CdS/CdTe heterojunction is in situ studied by synchrotron radiation photoemission spectroscopy (SRPES).The heterojunction is formed through stepwise deposition of a CdTe film on a wurtzite (0001)CdS single crystalline substrate via molecular beam *** shows an upward band bending of 0.55 eV,the valence band offset △Ev is calculated to be 0.65 e V and the conduction band offset △ Ec is 0.31 *** interracial band alignment is sketched to display type-Ⅰ band alignment.

关键词： alignment sketch bending

Electronic States of IC_(60)BA and PC_(71)BM

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Chinese Physics Letters 2013年第11期30卷 153-156页

作者： SHENG Chun-Qi WANG Peng SHEN Ying LI Wen-Jie ZHANG Wen-Hua zhu jun-fa LAI Guo-Qiao LI Hong-Nian Department of Physics Zhejiang UniversityHangzhou 310027 National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029 Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education Hangzhou Normal UniversityHangzhou 310012

We investigate the electronic states of IC_(60)BA and PC_(71)BM using first-principles calculations and photoelectron spectroscopy(PES)*** energy level structures for all possible isomers are reported and compared with those of C_(60),C_(70) and *** attachment of the side chains can raise the LUMO energies and decrease the HOMO-LUMO gaps,and thus helps to increase the power-conversion efficiency of bulk heterojunction solar *** the PES studies,we prepared IC_(60)BA and PC_(71)BM films on Si:H(111)substrates to construct adsorbate/substrate interfaces describable with the integer charge-transfer(ICT)*** measurements then revealed that one of the most important material properties for an electron acceptor,the energy of the negative integer charge-transfer state(E_(ICT)-),is 4.31 eV below the vacuum level for PC_(71)*** E_(ICT)- of IC_(60)BA is smaller than 4.14 eV.

关键词： integer isomers chains

Regulated reaction pathway of CO2 photoreduction into CH4 by metal atom pair sites

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Rare Metals 2024年第9期43卷 4620-4627页

作者： Dong-Po He Guang-Bing Huang jun Hu Yang Wu Xiao-Dong Li Qing-Xia Chen Shan zhu Wen-Sheng Yan jun-fa zhu Yang Pan Xing-Chen Jiao Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan University Hefei National Research Center for Physical Sciences at Microscale National Synchrotron Radiation LaboratoryUniversity of Science and Technology of China Max Planck Institute of Microstructure Physics State Grid Anhui Electric Power Research Institute

The carbon dioxide （CO2） reduction process involves complex protonation, making the resulting product often unpredictable. To achieve the desired product, it is crucial to manipulate the reaction steps. Herein, we build the metal atom pair sites for selective CO2photoreduction into methane. As a prototype, Ni atom pair sites loaded on the Mo S2nanosheets were synthesized and verified by highresolution transmission electron microscopy （HRTEM）,X-ray photoelectron spectroscopy （XPS） and X-rayabsorption near edge structure spectra （XANES）. In-situ Fourier transform infrared spectroscopy （FTIR） monitors the*CHO group, a crucial intermediate in CH4production,during CO2photoreduction on the Ni-Mo S2nanosheets,whereas this monitoring is not observed for the Mo S2nanosheets. Also, theoretical calculations disclose that over the Ni-Mo S2nanosheet slab, the formation energy of*CHO intermediates is determined to be lower （0.585 e V） than the desorption energy of*CO intermediates for CO production（0.64 e V）, implying the higher selectivity of CH4production. Accordingly, the Ni-Mo S2nanosheets demonstrate a methane formation rate of 27.21μmol·g-1·h-1, coupled with an impressive electron selectivity of 94.2%.

关键词： Nanosheets

Could π-aromaticity cross an unsaturated system to a fully saturated one?

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Chinese Chemical Letters 2024年第6期35卷 298-302页

作者： Shicheng Dong jun zhu State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials(iChem)Fujian Provincial Key Laboratory of Theoretical and Computational ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China School of Science and Engineering The Chinese University of Hong KongShenzhen 518172China

The classification of π-/σ-aromaticity depends on the electrons with the dominating ***,π-andσ-aromaticity are used to describe the unsaturated and saturated systems,***,it is rarely reported that π-aromaticity is dominated in a saturated *** we demonstrate that π-aromaticity could be dominating in several fully saturated four-membered rings(4MRs),supported by various aromaticity indices including ΔBL,NICS,EDDB,MCI,and Ad *** origin of suchπ-aromaticity in saturated rings could be attributed to an introduction of two additional electrons into the π-type LUMO of the parent neutral *** findings represent a novel approach to achieve π-aromaticity into a fully saturated system which has traditionally been dominated by σ-aromaticity.

关键词： π-Aromaticity Saturated rings Silicon

Topological Stability and Entropy for Certain Set-valued Maps

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Acta Mathematica Sinica,English Series 2024年第4期40卷 962-984页

作者： Yu ZHANG Yu jun zhu School of Mathematical Sciences Xiamen UniversityXiamen 361005P.R.China

In this paper,the dynamics(including shadowing property,expansiveness,topological stability and entropy)of several types of upper semi-continuous set-valued maps are mainly considered from differentiable dynamical systems points of *** is shown that(1)if f is a hyperbolic endomorphism then for eachε>0 there exists a C^(1)-neighborhood U of f such that the induced set-valued map F_(f,U)has theε-shadowing property,and moreover,if f is an expanding endomorphism then there exists a C^(1)-neighborhood U of f such that the induced set-valued map F_(f,U)has the Lipschitz shadowing property;(2)when a set-valued map F is generated by finite expanding endomorphisms,it has the shadowing property,and moreover,if the collection of the generators has no coincidence point then F is expansive and hence is topologically stable;(3)if f is an expanding endomorphism then for eachε>0 there exists a C^(1)-neighborhood U of f such that h(F_(f,U,ε))=h(f);(4)when F is generated by finite expanding endomorphisms with no coincidence point,the entropy formula of F is ***,the dynamics of the set-valued maps based on discontinuous maps on the interval are also considered.

关键词： Set-valued map orbit space hyperbolic endomorphism perturbation shadowing expansiveness topological stability entropy

Camera,LiDAR,and IMU Based Multi-Sensor Fusion SLAM:A Survey

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Tsinghua Science and Technology 2024年第2期29卷 415-429页

作者： jun zhu Hongyi Li Tao Zhang Department of Automation Tsinghua UniversityBeijing 100084China

In recent years,Simultaneous Localization And Mapping(SLAM)technology has prevailed in a wide range of applications,such as autonomous driving,intelligent robots,Augmented Reality(AR),and Virtual Reality(VR).Multi-sensor fusion using the most popular three types of sensors(e.g.,visual sensor,LiDAR sensor,and IMU)is becoming ubiquitous in SLAM,in part because of the complementary sensing capabilities and the inevitable shortages(e.g.,low precision and long-term drift)of the stand-alone sensor in challenging *** this article,we survey thoroughly the research efforts taken in this field and strive to provide a concise but complete review of the related ***,a brief introduction of the state estimator formation in SLAM is ***,the state-of-the-art algorithms of different multi-sensor fusion algorithms are *** we analyze the deficiencies associated with the reviewed approaches and formulate some future research *** paper can be considered as a brief guide to newcomers and a comprehensive reference for experienced researchers and engineers to explore new interesting orientations.

关键词： multi-sensor fusion Simultaneous Localization And Mapping(SLAM) navigation localization

Stereochemical editing:Catalytic racemization of secondary alcohols and amines

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Chinese Chemical Letters 2024年第5期35卷 17-31页

作者： jun Zhang Zhiyao Zheng Can zhu Department of Chemistry Fudan UniversityShanghai 200438China Department of Organic Chemistry Arrhenius LaboratoryStockholm UniversityStockholm 10691Sweden

Chiral alcohols and amines are important structural units widely existing in pharmaceuticals,agrochemicals,and food *** kinetic resolution(DKR)is an efficient strategy to deliver optically active alcohols and amines from their *** the development of DKR method,racemization catalyst plays as a crucial element with the requirement of compatibility with the kinetic resolution(KR)*** this paper,recent advance in the catalytic racemization of secondary alcohols and amines is summarized based on different types of racemizing intermediates,which are redox racemization via ketone/imine intermediates,racemization via radical intermediates,and racemization via carbocation *** racemization of secondary alcohols and amines is also enclosed.

关键词： Racemization Secondary alcohols Amines Kinetic resolution Dynamic kinetic resolution

Two simple memristive maps with adaptive energy regulation and digital signal process verification

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 382-394页

作者： Feifei YANG Lujie REN jun MA Zhigang zhu College of Electrical and Information Engineering Lanzhou University of TechnologyLanzhou 730050China Department of Physics Lanzhou University of TechnologyLanzhou 730050China School of Information Science and Engineering Dalian Polytechnic UniversityDalian 116034China

Mathematical models can produce desired dynamics and statistical properties with the insertion of suitable nonlinear terms,while energy characteristics are crucial for practical application because any hardware realizations of nonlinear systems are relative to energy *** involvement of memristive terms relative to memristors enables multistability and initial-dependent property in memristive *** this study,two kinds of memristors are used to couple a capacitor or an inductor,along with a nonlinear resistor,to build different neural *** corresponding circuit equations are derived to develop two different types of memristive oscillators,which are further converted into two kinds of memristive maps after linear *** Hamilton energy function for memristive oscillators is obtained by applying the Helmholz theorem or by mapping from the field energy of the memristive *** Hamilton energy functions for both memristive maps are obtained by replacing the gains and discrete variables for the memristive oscillator with the corresponding parameters and *** two memristive maps have rich dynamic behaviors including coherence resonance under noisy excitation,and an adaptive growth law for parameters is presented to express the self-adaptive property of the memristive maps.A digital signal process(DSP)platform is used to verify these *** scheme will provide a theoretical basis and experimental guidance for oscillator-to-map transformation and discrete map-energy calculation.

关键词： Hamilton energy Discrete memristor Self-adaptive regulation Digital signal process(DSP)implementation

DEM investigation of strength and critical state behaviours of granular materials under true triaxial loadings

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Particuology 2024年第2期85卷 198-212页

作者： Minyi zhu Guobin Gong jun Xia Stephen Wilkinson Department of Civil Engineering Xi'an Jiaotong-Liverpool UniversityChina Department of Civil Engineering and Industrial Design University of LiverpoolLiverpoolUK faculty of Engineering and Information Sciences University of Wollongong in DubaiUnited Arab Emirates

This paper investigates the strength and critical state(CS)behaviours of granular materials via DEM simulations of true triaxial drained tests under three different loading modes including constant b(in-termediate stress ratio)tests with constantσ'1(major principal stress),constant p(mean pressure)and constantσ'3(minor principal stress)*** this end,a series of samples are generated with the same particle size distribution,and with the confining stresses ranging from 100 kPa to 900 *** CS is achieved for all *** the macroscopic behaviours and the microscopic behaviours are examined and compared considering different loading modes,confining stresses and intermediate stress ratios(b).The critical state lines(CSLs)are found to be unique and independent of the loading modes,but dependent on the b *** CSLs with b=0 and b=1 form the two boundaries of CSLs respectively beyond which CSLs under all other b tests cannot go *** different strength criteria are examined and compared in terms of both peak and CS *** Mohr-Coulomb strength criterion is found to be only suitable for axisymmetric loading *** Lade-Duncan criterion is only suitable for describing peak strengths,which is dependent on the loading modes and confining *** Satake criterion and Matsuoka-Nakai criterion are the more appropriate strength criteria for describing CS failures,indicating that the CS values of both the Satake parameter and the Matsuoka-Nakai parameter describe an inherent property that characterizes the CS failure for a given type of *** CS mechanical coordination number is fitted by a curved line for a given b value,which is unique regardless of the loading *** peak and CS values of both major and minor principal fabric tensors decrease with increasing b values,while they increase with increasing b values for the intermediate principal fabric tensor.

关键词： Discrete element method Intermediate stress ratio Dilation Critical state failure criterion