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Palladium installed copper-organic framework for C–C coupling reactions

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Science China Chemistry 2025年

作者： yu-Mei Wang Mei-Xia Tao Kai-Ming Mo Xu Chen Shu-Hua Zhong Elena S Shubina Guo-Hong ning Dan Li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Supramolecular Coordination ChemistryJinan University A.n.nesmeyanov Institute of organoelement Compounds Russian Academy of Sciences

The formation of C–C bonds is a crucial aspect of organic synthesis. Synthesists' long-term objective is to identify novel catalysts to optimize reaction systems based on traditional transition metal catalysis. This study explores the synthesis and catalytic potential of palladium-installed covalent metal-organic frameworks(CMoFs) based on copper cyclic trinuclear units(Cu-CTUs). By incorporating palladium ions into the imine-based framework JnM-7 through a straightforward immersion method, we achieved a notable enhancement in catalytic activity for critical C–C coupling reactions, including C–H arylation and Sonogashira cross-coupling. The resulting JnM-7-Pd demonstrated remarkable stability and recyclability, maintaining its efficiency over at least three cycles without any decline in efficiency.

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Two-body nonleptonic decays of the heavy mesons in the factorization approach

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Frontiers of physics 2023年第6期18卷 107-126页

作者： Shuo-Ying yu Xian-Wei Kang V.o.Galkin Key Laboratory of Beam Technology of the Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China Federal Research Center“Computer Science and Control” Russian Academy of SciencesVavilov Street 40119333 MoscowRussia

In the framework of the factorization approach we calculate the branching fractions of 100 two-body nonleptonic decay channels in total,including 44 channels of the charm meson decays and 56 channels of the bottom meson *** charm meson decays,we test and confirm the previous observation that taking the limit for the number of colors n→∞significantly improves theoretical *** bottom meson decays,the penguin contributions are included in *** an essential input,we employ the weak decay form factors obtained in the framework of the relativistic quark model based on the quasi-potential *** form factors have well been tested by calculating observables in the semileptonic D and B meson decays and confronting obtained results with experimental *** general,the predictions for the nonleptonic decay branching fractions are ***,for a quantitative calculation it is necessary to account for a more subtle effects of the final-state interaction.

关键词： form factor quark model nonleptonic decay factorization method

Long-period eclipsing binaries:towards the true mass-luminosity *** test sample,observations and data analysis

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Research in Astronomy and Astrophysics 2020年第8期20卷 169-176页

作者： Alexei yu.Kniazev oleg yu.Maikov Ivan yu.Katkov Leonid n.Berdnikov South African Astronomical observatory P.O.Box 9ObservatoryCape Town7935South Africa Southern African Large Telescope P.O.Box 9ObservatoryCape Town7935South Africa Sternberg Astronomical Institute Lomonosov Moscow State UniversityMoscow119992Russia Institute of Astronomy of RAS Moscow 119017Russia new York University Abu Dhabi PO Box 129188Abu DhabiUAE Center for Astro Particleand Planetary PhysicsNYU Abu DhabiPO Box 129188Abu DhabiUAE

The mass-luminosity relation is a fundamental law of *** have suggested that the currently used mass-luminosity relation is not correct for the M/M⊙>2.7 range of mass since it was created utilizing double-lined eclipsing binaries,where the components are synchronized and consequently change each other's evolutionary *** exclude this effect,we have started a project to study longperiod massive eclipsing binaries in order to construct radial velocity curves and determine masses for the *** outline our project and present the selected test sample together with the first HRS/SALT spectral observations and the software package,FITTInG BInARY STARS(FBS),that we developed for the analysis of our spectral *** the first result,we present the radial velocity curves and best-fit orbital elements for the two components of the FP Car binary system from our test sample.

关键词： stars:luminosity function mass function stars:binaries:spectroscopic

Lithium mapping in a Mg-9Li-4Al-1Zn alloy using electron energy-loss spectroscopy

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Journal of Magnesium and Alloys 2023年第4期11卷 1170-1179页

作者： yu Zhang Laure Bourgeois yu Chen Zhuoran Zeng nick Birbilis Philip n.H.nakashima Department of Materials Science and Engineering Monash UniversityVIC 3800Australia Monash Centre for Electron Microscopy Monash UniversityVIC 3800Australia College of Engineering and Computer Science Australian National UniversityACT 2601Australia Faculty of Science Engineering and Built EnvironmentDeakin UniversityVIC 3125Australia

Magnesium-lithium alloys with high lithium content have been attracting significant attention because of their low density,high formability and corrosion *** properties are dependent on the distribution of lithium,which is difficult to map in the presence of *** this work,a ratio spectrum-imaging method with electron energy-loss spectroscopy(EELS)is demonstrated,which enables the mapping of *** application to LAZ941(Mg-9Li-4Al-1Zn in wt.%),this technique revealed that a key precipitate in the microstructure,previously thought by some to be Mg_(17)Al_(12),is in fact rich in *** result was corroborated with a structural investigation by high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM),showing this phase to be Al_(1-x)Zn_(x)Li,with xork indicates the potential offered by this technique for mapping lithium in materials.

关键词： Lithium mapping Magnesium alloys Electron energy-loss spectroscopy(EELS) High-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM)

Computer simulation of coal organic mass structure and its sorption properties

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International Journal of Coal Science & Technology 2019年第3期6卷 438-444页

作者： yu. n. Zhuravlev A. n. Porokhnov Kemerovo State University Kemerovo Russia

Structural model of C100H79o7nS coal organic mass was obtained within density functional theory in the localized orbital basis set using the B3LYP hybrid functional. The model was compared with the known experimental data for coal of different grades and its sorption properties were studied with respect to CH4, Co2 and H2o. It has been shown that macromolecule of coal organic mass has bulk structure with a pore inside it. Interaction between coal and CH4 molecules consists of typical physical adsorption with oligomer formation on the pore border, physical adsorption with elements of chemical adsorption was also observed between coal and H2o molecules. Interaction between coal and H2o molecules included both physical and chemical adsorbion.

关键词： Polycyclic compounds Coal organic mass Computer simulation IR-spectra Pore structure Methane

Recovering noble metals from waste streams using porous organic frameworks for heterogeneous catalysis

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Science China Chemistry 2024年第11期67卷 3578-3587页

作者： yu Pan Michelle Åhlén Maria Strømme Chao Xu Division of nanotechnology and Functional Materials Department of Materials Science and EngineeringÅngström LaboratoryUppsala UniversityUppsala 75121Sweden State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350117China

Recovering noble metals from waste resources and incorporating them into catalysts stands out as a promising strategy for advancing sustainability within the catalysis field. This review provides a comprehensive overview of recent investigations into noble metal recovery from waste streams, specifically employing porous organic frameworks(PoFs). Additionally, the study delves into the utilization of the resultant composites, enriched with noble metals, in heterogeneous catalysis. Moreover, we offer insights into the challenges faced and outline prospects for the practical implementation of extracting noble metal catalysts from waste streams using PoFs, aiming to develop cost-effective, sustainable, and efficient heterogeneous catalysts.

关键词： porous organic frameworks noble metal recovery heterogeneous catalysis sustainability

Dirac operator on the sphere with attached wires

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Chinese Physics B 2016年第4期25卷 335-338页

作者： E n Grishanov D A Eremin D A Ivanov I yu Popov ogarev Mordovia State University Bolshevistskaya Str. 68 Saransk Russia ITMo University Kroverkskiy pr. 49 St. Petersburg 197101 Russia

An explicitly solvable model for tunnelling of relativistic spinless particles through a sphere is suggested. The model operator is constructed by an operator extensions theory method from the orthogonal sum of the Dirac operators on a semi- axis and on the sphere. The transmission coefficient is obtained. The dependence of the transmission coefficient on the particle energy has a resonant character. one observes pairs of the Breit-Wigner and the Fano resonances. It correlates with the corresponding results for a non-relativistic particle.

关键词： Dirac operator nanostructure tunnelling solvable model

Luminescent Composite Films Based on Mechanically Strong Ladder-like Polyphenylsilsesquioxane and oligophenyleuropiumsiloxane

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Chinese Journal of Polymer Science 2024年第11期42卷 1793-1801,I0013页

作者： E.E.Kim T.o.Ershova A.S.Belova D.A.Khanin E.V.Bashkova G.G.nikiforova yu.n.Kononevich A.A.Anisimov o.I.Shchegolikhina A.M.Muzafarov A.n.nesmeyanov Institute of organoelement Compounds Russian Academy of SciencesMoscow119334Russian Federation Tula State Lev Tolstoy Pedagogical University Tula300026Russian Federation V.Topchiev Institute of Petrochemical Synthesis Russian Academy of Sciences Moscow119991Russian Federation Moscow Institute of Physics and Technology(national Research University) DolgoprudnyMoscow Region141700Russian Federation n.S.Enikolopov Institute of Synthetic Polymeric Materials Russian Academy of SciencesMoscow117393Russian Federation

nowadays organosilicon luminescent materials are of increasing interest due to the variety of their synthetic or modification techniques and application *** polyphenylsilsesquioxanes(L-PPSQ)are a unique class of organosilicon polymers,which can be ideal matrices for the luminescent composites due to their high thermal stability,optical transparency and mechanical *** this work,new mechanically strong,heat-resistant,transparent and sensitive to ammonia vapor luminescent composite films based on L-PPSQ have been *** the source of Europium ions oligophenyleuropiumsiloxane was used,demonstrating perfect compatibility to the matrix due to the similar *** improve luminescent properties of the films,new organosilicon ligands were introduced into the composites and their influence on the properties of the materials was *** properties of described composites may allow their further application as multifunctional coatings.

关键词： Luminescent composite films Ladder-like polyphenylsilsesquioxane oligophenyleuropiumsiloxane

CoMPUTER-AIDED DESIGn oF ADAPTIVE PULSED ARC WELDInG oF RooT WELDS BY MELTInG ELECTRoDE

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Acta Metallurgica Sinica(English Letters) 2000年第1期13卷 63-68页

作者： yu. n. Sarave o. I.Shpigunova(Institute of Shength Physics and Materials Science, Siberian Branch, Russian Academy of Sciences,Tom-sk, Russia)

The purpose of computer-aided design of new adaptive pulsed arc technologies of welding is: to de- sign optimum algorithms of pulsed control over main energy parameters of *** permits:to in- crease welding productivity, to stabilize the welding regime, to control weld formation,taking into ac- count its spatial position, to proveal specie strength of the welded and coatings. Computer- aided design reduces the time of development of new pulsed arc technology:provides the optimization of technological referes according to the operating conditions of welded joints,the prediction of the ser- vice life of the *** developed methodology of computer-aided design of advanced technologies, models, original software, adaptive algorithms of pulsed control, and spend equipment permits to regulate penetration,the weld shape, the sizes of heat - affected zone; to predict sired properties and quality of welded joints.

关键词： pulse welding,algorithm of control,computer- aided design