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Effect of Bi/Si Ratio of BiBSi Glass on Its Structure, Properties and Laser Sealing Shear Strength for Vacuum Glazing

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 13-24页

作者： liU Wei JIAO Jinxu LUO Dusha ZHOU Junjie SHI lifen WANG Weiwei li changqing WANG Peng XIONG Dehua li Hong State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China Silica-Based Materials Laboratory of Anhui Province CNBM Research Institute for Advanced Glass Materials Group Co.LtdBengbu 233018China State Key Laboratory of Advanced Technology for Float Glass CNBM Research Institute for Advanced Glass Materials Group Co.LtdBengbu 233018China

The low-melting glass of Bi2O_(3)-B2O_(3)-SiO_(2)(BiBSi)system was used for the first time for laser sealing of vacuum *** the condition of constant boron content,how the structure and properties vary with Bi/Si ratio in low-melting glass was *** addition,the relationships between laser power,low-melting glass solder with different Bi/Si ratios and laser sealing shear strength were *** results show that a decrease in the Bi/Si ratio can cause a contraction of the glass network of the low-melting glass,leading to an increase of its characteristic temperature and a decrease of its coefficient of thermal *** laser sealing,the copper ions in the low-melting glass play an endothermic role.A change in the Bi/Si ratio will affect the valence state transition of the copper ions in the low-melting *** absorbance of the low-melting glass does not follow the expected correlation with the Bi/Si ratio,but shows a linear correlation with the content of divalent copper *** greater the concentration of divalent copper ions,the greater the absorbance of the low-melting glass,and the lower the laser power required for laser *** shear strength of the low melting glass solder after laser sealing was tested,and it was found that the maximum shear strength of Z1 glass sample was the highest up to 2.67 MPa.

关键词： Bi2O_(3)-B2O_(3)-SiO_(2)(BiBSi) Bi/Si ratio low-melting glass laser sealing vacuum glazing

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Explicit concomitance of implicit method to solve vibration equation

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Earthquake Engineering and Engineering Vibration 2012年第2期11卷 269-272页

作者： li, changqing Jiang, lizhong School of civil engineering Central South University Changsha 410075 China

It has been proven that the implicit method used to solve the vibration equation can be transformed into an explicit method,which is called the concomitant explicit *** constant acceleration method's concomitant explicit method was used as an example and is described in detail in this *** relationship between the implicit method and explicit method is defined,which provides some guidance about how to create a new explicit method that has high precision and computational efficiency.

关键词： dynamic analysis explicit method implicit method structural dynamics

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B_n(BO)_n^(2-),CB_(n-1)(BO)_n^-,and C_2B_(n-2)(BO)_n (n=5-12):Cage-like boron oxide clusters analogous to closo-B_nH_n^(2-),CB_(n-1)H_n^-,and C_2B_(n-2)H_n

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Science China Chemistry 2011年第5期54卷 756-761页

作者： MIAO changqing li SiDian Institute of Materials Sciences and Department of Chemistry Xinzhou Teachers UniversityXinzhou 034000China

A density functional theory （DFT） investigation has been performed in this work on the cage-like boron-rich boron oxide clus-ters Bn（BO）n^2-,CBn-1（BO）n^-,and C2Bn-2（BO）n （n = 5–12） which are boronyl analogues of the closo-boranes BnHn2-,monocarbo-ranes CBn-1H-n,and dicarboranes C2Bn-2Hn. These boron oxide clusters possess similar geometrical and electronic structures with the corresponding boranes and carboranes and prove to be three-dimensional （3D） aromatic compounds,consistent with the previously proposed BO/H isolobal analogy. Neutral C2Bn-2（BO）n species possess considerably high ionization potentials in the range 12.0–12.7 eV and CBn-1H-n monoanions have the vertical electron detachment energies in the range 6.6–9.4 eV at the DFT level. BO terminals singly bonded to the skeletal vertexes through a B atom possess the characteristic stretching vi-brational frequencies at about 2000 cm-1,clearly indicating the existence of B-O triple bonds in these clusters. Experimental syntheses and characterizations of these interesting clusters may expand the structural concepts of boron oxides and bring im-portant applications for boron oxide clusters as molecular devices in chemistry and new materials in boron neutron capture therapy.

关键词： boron oxide clusters boronyl group density functional theory geometrical structures electronic structures aromaticities

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Effect of Bi/Si Ratio of BiBSi Glass on Its Structure,Properties and Laser Sealing Shear Strength for Vacuum Glazing

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期 13-24页

作者：刘伟 JIAO Jinxu LUO Dusha ZHOU Junjie SHI lifen WANG Weiwei li changqing WANG Peng XIONG Dehua 李宏 State Key Laboratory of Silicate Materials for Architectures Wuhan University of Technology Silica-Based Materials Laboratory of Anhui Province CNBM Research Institute for Advanced Glass Materials Group Co. Ltd State Key Laboratory of Advanced Technology for Float Glass CNBM Research Institute for Advanced Glass Materials Group Co. Ltd

The low-melting glass of Bi2O3-B2O3-SiO2（BiBSi） system was used for the first time for laser sealing of vacuum *** the condition of constant boron content,how the structure and properties vary with Bi/Si ratio in low-melting glass was *** addition,the relationships between laser power,low-melting glass solder with different Bi/Si ratios and laser sealing shear strength were *** results show that a decrease in the Bi/Si ratio can cause a contraction of the glass network of the low-melting glass,leading to an increase of its characteristic temperature and a decrease of its coefficient of thermal *** laser sealing,the copper ions in the low-melting glass play an endothermic role.A change in the Bi/Si ratio will affect the valence state transition of the copper ions in the low-melting *** absorbance of the low-melting glass does not follow the expected correlation with the Bi/Si ratio,but shows a linear correlation with the content of divalent copper *** greater the concentration of divalent copper ions,the greater the absorbance of the low-melting glass,and the lower the laser power required for laser *** shear strength of the low melting glass solder after laser sealing was tested,and it was found that the maximum shear strength of Z1 glass sample was the highest up to 2.67 MPa.

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Surface nanostructure formation mechanism of 45 steel induced by supersonic fine particles pombarding

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Journal of University of Science and Technology Beijing 2008年第5期15卷 561-567页

作者： Dema Ba Shining Ma changqing li Fanjun Meng Department of Remanufacture Engineering Academy of Armored Force Engineering Beijing 100072 China

By means of supersonic fine particles bombarding （SFPB）,a nanostructured surface layer up to 15 μm was fabricated on a 45 steel plate with ferrite and pearlite phases. To reveal the grain refinement mechanism of SFPB-treated 45 steel,microstructure features of various sections in the treated surface were systematically characterized by X-ray diffraction （XRD）,scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. Grain size increases with an increase of depth from the treated surface. Plastic deformation and grain refinement processes are accompanied by an increase in strain. Plastic deformation in the proeutectoid ferrite phases has precedence over the pearlite phases. Grain refinement in the ferrite phases involves： the onset of dislocation lines （Dls）,dislocation tangles （DTs） and dense dislocation walls （DDWs） in the original grains; the formation of fine lamellar and roughly equiaxed cells separated by DDWs; by dislocation annihilation and rearrangement,the transformation of DDWS into subboundaries and boundaries and the formation of submicron grains or subgrains; the successive subdivision of grains to finer and finer scale,resulting in the formation of highly misoriented nano-grains. By contrast,eutectoid cementite phase accommodated strain in a sequence as follows： onset of elongated,bended and shear deformation under deformation stress of ferrites,short and thin cementites with a width of about 20-50 nm and discontinuous length were formed. Shorter and thinner cementites were developed into ultra-fine pieces under the action of high density dislocation and strains. At the top surface,some cementites were decomposed under severe plastic deformation. Experimental evidences and analysis indicate that surface nanocrystallization of 45 steel results from dislocation activities,high strains and high strain rate are necessary for the formation of nanocrystallites.

关键词： surface nanocrystallization grain refinement mechanism microstructure 45 steel

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A new type of quadratic acceleration method

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Frontiers of Structural and Civil Engineering 2010年第3期4卷 302-310页

作者： changqing li Menglin LOU State Key Laboratory for Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

The polynomial acceleration method for time history analysis is presented,in which accelerations between several equal neighboring time steps were assumed to be a polynomial function of time *** a higher order polynomial used,a higher accuracy can be obtained,but the stability field of the method becomes *** stability field and computational accuracy are taken into account at the same time,the quadratic acceleration method is superior to linear and cubic acceleration methods in choosing the maximum acceptable time step *** is also shown that the quadratic acceleration method has desirable arithmetic damp,amplitude decay rate and period elongation rate,though its conditional stability restricts its application in stiff structures.

关键词： polynomial acceleration method convergence stability square acceleration method

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Copolymerization of Acrylonitrile/1-Vinyl-3-Ethylimidazolium Bromide and Rheological, Thermal Properties of the Copolymer

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Transactions of Tianjin University 2019年第1期25卷 85-90页

作者： Yuanjian Tong Bowen Zhang changqing li lianghua Xu State Key Laboratory of Organic–Inorganic Composites Beijing University of Chemical Technology Key Laboratory of Carbon Fiber and Functional Polymer Ministry of Education Beijing University of Chemical Technology

Acrylonitrile(AN)/1-vinyl-3-ethylimidazolium bromide(VIMB) copolymer was prepared via solution polymerization using dimethyl sulfoxide(DMSO) as a solvent and azodiisobutyronitrile as an initiator. The effects of comonomer VIMB on the polymerization, rheological properties of the polymer solution and thermal properties of the copolymer were investigated. The ionic liquid VIMB resulted in higher polymerization conversion ratio and higher average molecular weight when copolymerized with AN than itaconic acid(ITA). Rheological measurements indicated that the transition shear rate increased linearly with increasing temperature for P(AN/ITA)/DMSO solution, while an exponential growth with temperature was observed for P(AN/VIMB)/DMSO solution. The exothermic peaks of DSC curves in N_2 appeared at 276.67 and 257.34 °C for P(AN/VIMB) and P(AN/ITA), respectively. As a potential comonomer of AN for PAN carbon fibers, the VIMB resulted in about 7% higher char yield in N_2, and 23.7% less weight loss at 600 °C in air than ITA copolymer.

关键词： Carbon fiber Copolymer Polyacrylonitrile Ionic liquid Thermal properties

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Optimal joint relay selection and resource allocation with QoS constraints in multiuser OFDM-based cellular networks

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High Technology Letters 2011年第3期17卷 305-310页

作者： Chen Dan Ji Hong li Xi Luo changqing Beijing University of Posts and Telecommunications Beijing 100876 P. R. China

This paper investigates the relay selection and resource allocation problem in multiuser orthogonal frequency division multiplexing （OFDM） based cooperative cellular networks, in which user nodes could relay information for each other using the decode-and-forward （DF） protocol to achieve spatial diversity gain. Specifically, the paper proposes an optimal joint relay selection and resource allocation （0RSRA） algorithm whose objective is to maximize system total achievable data rate with the constraints of each user＇ s individual quality of service （QoS） requirement and transmission power. Due to being a mixed binary integer programming （MBIP） problem, a novel two-level Lagrangian dual-primal decomposition and subgradient projection approach is proposed to not only select the appropriate cooperative relay nodes, but also allocate subcarries and power optimally. Simulation re- suits demonstrate that our proposed scheme can efficiently enhance overall system data rate and guarantee each user＇ s QoS requirement. Meanwhile, the fairness among users can be improved dramatically.

关键词： cooperative diversity relay selection resource allocation Lagrangian dual-primal decomposition

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Accurate Registration of Remote Sensing Images Based on Local Optimal Transformation

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Journal of Beijing Institute of Technology 2019年第2期28卷 371-382页

作者： Bo Wang changqing li Shi Tang Zhiqiang Zhou Hong Zhao School of Automation Beijing Institute of TechnologyBeijing 100081China Beijing Urban Construction Design&Development Group Co. Ltd.Beijing 100071China Beijing Navigation Control Technology Co. Ltd.Beijing 102200China

As the basic work of image stitching and object recognition,image registration played an important part in the image processing *** previous work in registration accuracy and realtime performance progressed very slowly,especially in registrating images with line *** innovative method for image registration based on lines is proposed,it can effectively improve the accuracy and real-time performance of image *** line feature can deal with some registration problems where point feature does not *** registration process is divided into two *** first part determines the rough registration transformation relation between reference image and test *** the similarity degree among different transformation and modified nonmaximum suppression(MNMS)algorithms are obtained,which produce local optimal solution to optimize the rough registration *** final optimal registration relation can be obtained from two registration parts according to the match *** experimental results show that the proposed method makes a more accurate registration relation and performs better in real-time situation.

关键词： initial registration relationship accurate registration relationship similarity degree local optimal transformation modified non-maximum suppression(MNMS)algorithm

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Drosophila RecQ5 is required for efficient SSA repair and suppression of LOH in vivo

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Protein & Cell 2010年第5期1卷 478-490页

作者： Yixu Chen Wen Dui Zhongsheng Yu changqing li Jun Ma Renjie Jiao State Key Laboratory of Brain and Cognitive Science Institute of BiophysicsChinese Academy of Sciences15 Datun RoadBeijing 100101China Graduate School of the Chinese Academy of Sciences Beijing 100080China Divisions of Biomedical Informatics and Developmental Biology Cincinnati Children’s Hospital Research Foundation3333 Burnet AvenueCincinnatiOH 45229USA

RecQ5 in mammalian cells has been suggested to suppress inappropriate homologous ***,the specific pathway(s)in which it is involved and the underlining mechanism(s)remain poorly *** took advantage of genetic tools in Drosophila to investigate how Drosophila RecQ5(dRecQ5)functions in vivo in homologous recombination-mediated double strand break(DSB)*** generated null alleles of dRecQ5 using the targeted recombination *** mutant animals are homozygous viable,but with growth retardation during *** mutants are sensitive to both exogenous DSB-inducing treatment,such as gamma-irradiation,and endogenously induced double strand breaks(DSBs)by I-Sce I *** the absence of dRecQ5,single strand annealing(SSA)-mediated DSB repair is compromised with compensatory increases in either inter-homologous gene conversion,or non-homologous end joining(NHEJ)when inter-chromosomal homologous sequence is *** of function of dRecQ5 also leads to genome instability in loss of heterozygosity(LOH)***,our data demonstrate that dRecQ5 functions in SSA-mediated DSB repair to achieve its full efficiency and in suppression of LOH in Drosophila.

关键词： Drosophila RecQ5 double strand break repair homologous recombination nonhomologous end joining single strand annealing RecQ helicase

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