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Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic h2O2 synthesis coupled with biomass valorization

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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： Jiaye Li shuang Pan Yihuang chen Qiong Liu College of Chemistry and Materials Engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （h2O2） synthesis presents a green and costeffective production ***,achieving highly selective h2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to h2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for h2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （sCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of h2O2coupled with biomass valorization.

关键词： Atomic economy Radical pathway regulation Rubidium atom coordination Biomass valorization

ON ThE GLOBAL sTABILITY CONJECTURE OF ThE GENOTYPE sELECTION MODEL

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Acta Mathematica scientia 2011年第2期31卷 512-528页

作者： s.h. saker Department of Mathematics King Saud University Department of Mathematics Faculty of Science Mansoura University

In 1994, Grove, Kocic, Ladas, and Levin conjectured that the local stability and global stability conditions of the fixed point -y= 1/2 in the genotype selection model should be equivalent. In this article, we give an affirmative answer to this conjecture and prove that local stability implies global stability. some illustrative examples are included to demonstrate the validity and applicability of the results.

关键词： Local stability global stability discrete genotype selection model

self-propagating high temperature synthesis of Mosi_2 matrix composites

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Rare Metals 2006年第3期25卷 225-230页

作者： Akhtar Farid s.h. Islam Materials science and Engineering s.h.ol State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

Mosi2 is presently regarded as the most important material for electrical heating and as one with huge potential for high temperature structural uses. Mosi2 and Mosi2 matrix composites were prepared by self-propagating high temperature synthesis （shs）. Pure Mosi2 was obtained and a compound of Mosi2 and Wsi2was synthesized in the form of predominant solid solution （Mo,W）si2. By adding aluminum of 5.5 at.% to Mo-si, the crystal structure of Mosi2 changed into a mixture of tetragonal Cllb Mosi2and hexagonal C40 Mo（si,Al）2. The （Mo,W）si2-Mo（si,Al）2-W（si,Al）2 composite materials were synthesized by adding aluminum of 5.5 at.% to Mo-W-si. however, if the amount of the added aluminum was not larger than 2.5 at.%, it did not have any significant effect. shs is an effective technology for synthesis of Mosi2 and Mosi2 matrix composites.

关键词： powder metallurgy Mosi2 matrix composites self-propagating high temperature synthesis molybdenumtungsten disilicide molybdenum aluminosilicide

Ideals Whose First Two Betti Numbers Are Close

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Algebra Colloquium 2015年第4期22卷 671-676页

作者： Keivan Borna s.h. hassanzadeh Faculty of Mathematical sciences and Computer Kharazmi University Tehran Iran School of Mathematics Institute for Research in Fundamental Sciences (IPM) Tehran Iran Faculty of Mathematical sciences and Computer Kharazmi University Tehran Iran Institute of Mathematics Universidade Federal de Rio de Janeiro Brasil

For an ideal I of a Noetherian local ring （R, m, k） one hasβR1（I） -β0R（I） ≥-1. It is demonstrated that some residual intersections of an ideal I for whichβ1R（I） -β0R（I） = -1 or 0 are perfect.

关键词： Betti numbers linlkage theory perfect Gorenstein ideals residual intersection

Electronic structure and ultraviolet spectra of p-C_(6)h_(4)-C_(20)

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原子与分子物理学报 2025年第3期42卷 21-28页

作者： chen Xin s.h.ol of Materials and Chemical Engineering West Anhui UniversityLu’an 237012China

Geometry optimization of p-C_(6)h_(4)-connected cyclo[20]carbon(p-C_(6)h_(4)-C_(20))was carried out at M062X/6-311G(d,p)level,three kinds of bond orders(Mayer,Laplacian,and Wiberg),electron-hole distributions,localized orbital locators(LOL),and infrared(IR)spectrum were also performed at the same *** on TD-DFT M062X/6-311G(d,p)method,the first 20 excited states and ultraviolet(UV)spectra of p-C_(6)h_(4)-C_(20) were *** results of π-electron delocalization analyses prove thatπ-electron delocalization of p-C_(6)h_(4)-C_(20) is more likely to occur on shorter C-C bonds rather than longer C-C bonds,and inside/outside of the ring plane rather than above/below the ring *** absorption peaks of p-C_(6)h_(4)-C_(20) locate at about 319 nm and 236 nm,respectively.

关键词： p-C_(6)h_(4)-C_(20) Bone orders UV spectrum Electron-hole analyses π-electron delocalization analyses

Investigation of Micro Formability of Bulk Amorphous Alloy in the supercooled Liquid state Based on Fluid Flow and Finite Element Analysis

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Journal of Materials science & Technology 2009年第2期25卷 277-280页

作者： M. cheng s.h. Zhang Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Research results on the viscous flow deformation behavior of bulk amorphous alloy in different systems are reviewed. The material exhibits an ideal Newtonian fluid at a high temperature. Analytical solution of lamellar fluid flow behavior is used to discuss the viscous flow behavior of the bulk amorphous alloy in the supercooled liquid state. A material model, which describes such deformation behavior of Mg6oCusoYlo amorphous alloy, is introduced into the finite element method of microformin8 process. surface feature size was investigated and found not sensitive to the micro formability. Bulk amorphous alloy may possibly be applied to microelectro-mechanical-systems （MEMs） fabrication.

关键词： Bulk amorphous alloy supercooled liquid state Micro formability Lamellar fluid flow

CFD-DEM simulation of a pseudo-two-dimensional spouted bed comprising coarse particles

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Particuology 2019年第2期17卷 171-180页

作者： B. Mahmoodi s.h. hosseini G. Ahmadi llam Gas Treating Company llam Iran Department of Chemical Engineering llam University llam 69315-516 Iran Department of Mechanical and Aeronautical Engineering Clarkson University Potsdam NY 13699-5725 USA

In the present study, computational fluid dynamics (CFD) and the discrete element method (DEM) are used in conjunction with the Eulerian-Lagrangian method to simulate a pseudo-two-dimensional spouted bed comprising coarse 6-mm particles. The open-source OpenFOAM code is used to solve the governing equations. The predicted vertical particle velocity along the bed axis, particle velocity profiles in the radial directi on, power spectral den sity, time-averaged particle velocity vectors, bed pressure drop, and solid flow pattern are evaluated and compared with existing experimental data. Good agreement is found between the CFD-DEM results and the measured data. It is also shown that the present CFD-DEM model accurately predicts the particle flow pattern throughout the bed. It is found that the drag force, solid stresses, and gravity play important roles in the CFD-DEM simulation of a spouted bed comprising coarse particles.

关键词： CFD-DEM Pseudo-2D spouted bed hydrodynamics Coarse particles

Mathematical modeling and simulation of the interface region of a tri-layer composite material,brass-steel-brass,produced by cold rolling

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International Journal of Minerals,Metallurgy and Materials 2009年第2期16卷 189-196页

作者： h. Arabi s.h. seyedein A. Mehryab B. Tolaminejad s.h.ol of Metallurgy and Materials Engineering Iran University of Science and TechnologyIUSTNarmakTehranIran

The object of this study was to find the optimum conditions for the production of a sandwich composite from the sheets of brass-steel-brass. The experimental data obtained during the production process were used to validate the simulation program, which was written to establish the relation between the interface morphology and the thickness reduction amount of the composite. For this purpose, two surfaces of a steel sheet were first prepared by scratching brushing before inserting it between two brass sheets with smooth surfaces. Three sheets were then subjected to a cold rolling process for producing a tri-layer composite with various thick- nesses. The sheet interface after rolling was studied by different techniques, and the bonding strength for each rolling condition was determined by peeling test. Moreover, a relation between interfacial bonding strength and thickness reduction was found. The simulation results were compared with the experimental data and the available theoretical models to modify the original simulation program with high application efficiency used for predicting the behavior of the interface under different pressures.

关键词： sandwich composite cold rolling mathematical simulation metallic bonding interface

EMBRITTLEMENT OF A Cr-Mo LOW-ALLOY sTEEL DUE TO LOW-TEMPERATURE NEUTRON IRRADIATION

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Acta Metallurgica sinica(English Letters) 2006年第1期19卷 20-26页

作者： s.h. song L. Q. Weng Department of Materials science and Engineering Shenzhen Graduate School HarbinInstitute of Technology Shenzhen 518055 China

Embrittlement of a Cr-Mo2.25CrlMo steel stemming from neutron irradiation at 270℃ is studied by virtue of small punch testing in conjunction with scanning electron microscopy. The ductile-brittle transition temperature determined by the small punch test is much lower than that determined by the standard Charpy test. There is some irradiation-induced embrittlement effect after the steel is irradiated for 46 days with a neutron dose rate of 1.05×10^18dpa/s （displacement per atom per second）.

关键词： irradiation embrittlement segregation low alloy steels pressure vessel