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High-throughput predictions of metal-organic framework electronic properties:theoretical challenges,graph neural networks,and data exploration

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npj Computational materials 2022年第1期8卷 1053-1062页

作者： Andrew S.Rosen victor Fung Patrick Huck Cody T.O’Donnell matthew K.Horton Donald G.Truhlar Kristin A.Persson Justin m.Notestein Randall Q.Snurr Department of materials Science and Engineering University of CaliforniaBerkeleyCA94720USA miller Institute for Basic Research in Science University of CaliforniaBerkeleyBerkeleyCA94720USA materials Science Division Lawrence Berkeley National LaboratoryBerkeleyCA94720USA Department of Chemical and Biological Engineering Northwestern UniversityEvanstonIL60208USA Center for Nanophase materials Sciences Oak Ridge National LaboratoryOak RidgeTN37831USA Energy Technologies Area Lawrence Berkeley National LaboratoryBerkeleyCA94720USA Department of Chemistry Chemical Theory Centerand Minnesota Supercomputing InstituteUniversity of MinnesotaMinneapolisMN55455USA molecular Foundry Lawrence Berkeley National LaboratoryBerkeleyCA94720USA

With the goal of accelerating the design and discovery of metal–organic frameworks(mOFs)for electronic,optoelectronic,and energy storage applications,we present a dataset of predicted electronic structure properties for thousands of mOFs carried out using multiple density functional *** to more accurate hybrid functionals,we find that the widely used PBE generalized gradient approximation(GGA)functional severely underpredicts mOF band gaps in a largely systematic manner for semi-conductors and insulators without magnetic ***,an even larger and less predictable disparity in the band gap prediction is present for mOFs with open-shell 3d transition metal *** regards to partial atomic charges,we find that different density functional approximations predict similar charges overall,although hybrid functionals tend to shift electron density away from the metal centers and onto the ligand environments compared to the GGA point of *** more significant differences in partial atomic charges are observed when comparing different charge partitioning *** conclude by using the dataset of computed mOF properties to train machine-learning models that can rapidly predict mOF band gaps for all four density functional approximations considered in this work,paving the way for future high-throughput screening *** encourage exploration and reuse of the theoretical calculations presented in this work,the curated data is made publicly available via an interactive and user-friendly web application on the materials Project.

关键词： charges electronic centers

Specificity of electrophysical and gas-sensitive properties of nanocomposite ZnO–TiO_(2) films formed by solid-phase pyrolysis

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ChemPhysMater

ChemPhysmater 2024年第3期3卷 314-319页

作者： victor V.Petrov maria G.Volkova Alexsandra P.Ivanishcheva Gleb V.Tolstyak Ekaterina m.Bayanb Institute of Nanotechnologies Electronicsand Equipment EngineeringSouthern Federal UniversityTaganrog 347922Russia Faculty of Chemistry Southern Federal UniversityRostov-on-Don 344090Russia

ZnO–TiO_(2) thin films containing 0.5 mol%,1.0 mol%,and 5.0 mol%ZnO were synthesized by oxidative solidphase *** materials contained anatase and rutile phases with particle size of 6–13 nm,as confirmed using X-ray phase analysis and scanning electron *** a certain number of ZnO crystallites appeared in the TiO_(2) film structure in the temperature range of room temperature to 220℃,a two-level response of the film resistance was observed,differing by approximately 10%,as obtained by electrophysical *** two-level response correlates with the formation of two donor energy levels of 0.28 and 0.33 eV in the band structure of the ZnO–TiO_(2) *** donor level with a higher activation energy corresponded to the Ti vacancy(V−Ti),and that with a lower activation energy corresponded to the Zn vacancy(V−Zn).Two levels of gas-sensitive properties were noted for 0.5ZnO–TiO_(2),1ZnO–TiO_(2),and 5ZnO–TiO_(2) under the influence of 50 ppm NO_(2) at 250℃.Such two-level responses can be ascribed to the pinning of the Fermi level on ZnO and TiO_(2) *** mechanism of the beak-shaped and two-level responses of sensors based on composite nanomaterials when exposed to various gases was elucidated.

关键词： Thin film ZnO TiO_(2) Nanocomposites Pyrolysis Gas sensors

Influence of monovalent Bi^+doping on real composition,point defects,and photoluminescence in TlCdCl3 and TlCdI3 single crystals

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Science China materials 2017年第12期60卷 1253-1263页

作者： Daria N.Vtyurina Polina A.Eistrikh-Geller Galina m.Kuz mlcheva victor B.Rybakov Evgeny V.Khramov Irina A.Kaurova Dmitry Yu.Chernyshov Vladimir N.Korchak Semenov Institute of Chemical Physics Russian Academy of SciencesMOSCOW 119991Russia Institute of Fine Chemical Technologies Moscow Technological UniversityMoscow 119571Russia Lomonosov State University Moscow 119992Russia National Research Center《Kurchatov Instituters》 Moscow 123182Russia Swiss-Norwegian Beamlines at the European Synchrotron Radiation Facility Grenoble 38000France

The structural features and real compositions with point defects of Bi+-doped TlCdCl_3 and TlCdI_3 single crystals, grown by the Bridgman-Stockbarger technique, are first studied using the X-ray diffraction, X-ray synchrotron radiation, and EXAFS/XANES spectroscopy. In the structures of Bi^+-doped TlCdCl_3 and TlCdI_3 crystals, the Cd, Cl, and I sites are found to be defect-free. The vacancies in the Tl sites and interstitial Bi atoms located in the vicinity of the Tl sites are detected in the structures of both samples. In the Bi^+-doped TlCdCl_3, the presence of a small amount of Bi^+ ions in the Tl^+ sites is possible. The correlation between photoluminescence bands and point defects in the refined structures are determined. Photoluminescence spectra and decay kinetics of the Bi+-doped TlCdCl_3 and TlCdI_3 demonstrate that they are attractive materials for potential applications in photonics.

关键词： single crystal growth doping crystal structure point defects photoluminescence

Room temperature synthesis of two-dimensional multi layer magnets based on α-Co^(Ⅱ) layered hydroxides

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Nano materials Science 2022年第1期4卷 36-43页

作者： victor Oestreicher Christian Dolle Diego Hunt michael Fickert Gonzalo Abellan Instituto de Ciencia molecular(ICmol).Universidad de Valencia Catedritico Jose Beltran 2PaternaValencia46980Spain Departamento de Física de la materia Condensada GIy A.Instituto de Nanociencia y NanotecnologíaCNEA-CAC-CONICET.Av.Gral.PazSan MartinBuenas Aires1650Argentina Chair of Organic ChemistryⅡand Joint Institute of Advanced materials and Processes(ZmP).Friedrich-Alexander-Universitát Erlangen-Nürnberg(FAU) Nikolaus-Fiebiger Strasse 1091058 Erlangen and Dr.-Mack Strasse 81Furth 90762Germany

Research on two-dimensional(2D) materials is one of the most active fields in materials science and nanotechnology. Among the members of the 2D family, layered hydroxides(LHs) represent an exceptional case of study due to their unparalleled chemical versatility which allows the modulation of their physicochemical properties at will. Nowadays, LHs based on earth-abundant metals are key materials in the areas of energy storage and conversion, hybrid materials or magnetism. α-Co hydroxides(Simonkolleite-like structures) are promising phases with tuneable electronic and magnetic properties by ligand modification. However, even in the simple case of α-Co^(Ⅱ) hydroxychlorides, the preparation of well-defined large 2D crystals is not straightforward, hindering the development of fundamental studies. Herein, we present the synthesis of 2D hexagonal crystals with outstanding sizethickness relationship(diameter > 5 μm and thickness of 20 ± 7 nm) by a simple homogeneous synthesis taking place at room temperature. In structural terms, no differences are observed between our layered materials and those obtained hydrothermally. However, dynamic susceptibility measurements alert about different arrangements of the magnetic sublattices, which have been rationalized with structural DFT calculations. This work provides an extremely easy bottom-up method to obtain high-quality 2D crystals based on α-CoIIhydroxides,paving the way for the development of fundamental studies and applications.

关键词： Two-dimensional(2D)materials Layered hydroxides Hexagonal morphology Bottom-up synthesis magnetism

基于大型声学风洞的飞行器起落架噪声试验研究

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振动与冲击 2022年第22期41卷 160-172,210页

作者：赵鲲梁俊彪 Kopiev victor Belyaev Ivan 中国空气动力研究与发展中心低速空气动力研究所气动噪声控制重点实验室四川绵阳621000 俄罗斯中央空气流体动力研究院气动噪声部莫斯科105005

起落架是飞行器机体噪声的主要声源,是当前气动声学界关注的一个焦点。为分析不同结构参数对起落架噪声特征的影响,在FL-175.5 m×4.0 m航空声学风洞开展了大尺度起落架简化模型试验研究。试验包括34 m/s~75 m/s内5个风速,采用自由场传... 详细信息

起落架是飞行器机体噪声的主要声源,是当前气动声学界关注的一个焦点。为分析不同结构参数对起落架噪声特征的影响,在FL-175.5 m×4.0 m航空声学风洞开展了大尺度起落架简化模型试验研究。试验包括34 m/s~75 m/s内5个风速,采用自由场传声器与相位传声器阵列开展声学测量。试验系统分析了模型噪声源位置、部件贡献与噪声指向性规律,获得了风速变化下起落架噪声特征;通过控制结构参数,结果表明起落架高度、轮直径、攻角、轮数、轮攻角对起落架噪声特征具有重要影响,而8°范围内偏角影响相对较弱。

关键词：起落架噪声大型声学风洞 CLEAN-SC 声源区域积分国际合作

Observation of nonlinear fractal higher order topological insulator

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Light(Science & Applications) 2024年第11期13卷 2699-2714页

作者： Hua Zhong victor O.Kompanets Yiqi Zhang Yaroslav V.Kartashov meng Cao Yongdong Li Sergei A.Zhuravitskii Nikolay N.Skryabin Ivan V.Dyakonov Alexander A.Kalinkin Sergei P.Kulik Sergey V.Chekalin victor N.Zadkov Key Laboratory for Physical Electronics and Devices Ministry of EducationSchool of Electronic Science and EngineeringXi’an Jiaotong University710049 Xi’anChina Institute of Spectroscopy Russian Academy of SciencesTroitskMoscow 108840Russia Quantum Technology Centre Faculty of PhysicsM.V.Lomonosov Moscow State UniversityMoscow 119991Russia Faculty of Physics Higher School of EconomicsMoscow 105066Russia

Higher-order topological insulators(HOTIs)are unique materials hosting topologically protected states,whose dimensionality is at least by 2 lower than that of the *** states in such insulators may be strongly confined in their corners which leads to considerable enhancement of nonlinear processes involving such ***,all nonlinear HOTIs demonstrated so far were built on periodic bulk lattice ***,we demonstrate the first nonlinear photonic HOTI with the fractal *** their fractional effective dimensionality,the HOTIs constructed here on two different types of the Sierpiński gasket waveguide arrays,may support topological corner states for unexpectedly wide range of coupling strengths,even in parameter regions where conventional HOTIs become *** demonstrate thresholdless spatial solitons bifurcating from corner states in nonlinear fractal HOTIs and show that their localization can be efficiently controlled by the input beam *** observe sharp differences in nonlinear light localization on outer and multiple inner corners and edges representative for these fractal *** findings not only represent a new paradigm for nonlinear topological insulators,but also open new avenues for potential applications of fractal materials to control the light flow.

关键词： materials. flow. topological

Jokes,Cartoon and Wisdom Words

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英语沙龙（初级版） 2010年第12期 52-53页

作者： victor

JokeA woman who had thrown a dinner party, at whichraw oysters, curried lamb, and steamed musselswere all served, met her physician on the street thefollowing day. "I’m sorry you weren’t able to come tomy party last... 详细信息

关键词：英语教学教学方法阅读英语翻译

Water absorption characteristics of Canarium Schweinfurthii fruits

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Information Processing in Agriculture 2019年第3期6卷 386-395页

作者： James Chinaka Ehiem victor Ifeanyichukwu Obiora Ndirika Udochukwu Nelson Onwuka Yvan Gariepy Vijayan Raghavan Department of Agricultural and Bio-Resources Engineering Michael Okpara University of AgricultureUmudikeP.M.B.7267UmuahiaAbia StateNigeria Department of Bioresources Engineering McGill UniversityMacdonald Campus21111 LakeshoreSte-Anne-de-BellevueQuebec H9X 3V9Canada

Water absorption characteristics of two varieties of Canarium Schweinfurthii ***(Canarium Schweinfurthii *** and short)essential for predicting their suitable absorption conditions was investigated at three different temperatures(35,50,65C).Increase in moisture content of the fruits was measured at one-hour interval until constant values were obtained after five successive intervals of moisture *** of soluble constituents,textural and nutritive qualities of the rehydrated products and their thermodynamic behavior were also measured and *** results obtained revealed that saturation time for 35,50 and 65C of long and short varieties are 14,18 and 40 h and 18,22 and 36 h *** of absorption of the fruits differ significantly(p>0.05)with temperature and not with the *** absorption rate of Canarium Schweinfurthii *** and short varieties are 2.71 and 2.25 kg/h *** moisture bearing capacity,textural,and nutritive qualities of the reconstituted products showed no significant difference among varieties at different temperatures *** soaked at 35C produced reusable residual water,retained their nutritive values and soluble constituent more than other soaking temperatures ***,the absorption reaction is endothermic with negative entropy and Gibbs energy values were above *** model had the best quality for describing the absorption characteristics of both Canarium Schweifurthii ***.

关键词： Absorption Canarium Thermodynamics Temperature Fruits moisture

Ductility of seismic resistant steel structures

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