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Chemical Research in Chinese Universities 2001年第1期17卷 63-68页

作者： GAO Jin sheng ma Zhong guo YE Ling BU Wei ming ma dong sheng YU Chang hua GE Yue FAN Yu guo Department of Chemistry Heilongjiang UniversityHarbin 150080P.R.China Key Laboratory of Supramolecular Structure and Spectroscopy Jilin UniversityChangchun 130023P.R.China

The novel complexes, Cp(CO) 2FeTiCp 2Cl(1) and Cp(CO) 2FeSn(CH 2CMe 2Ph) 3(2), were synthesized and characterized by means of elemental analyses and IR spectra, Cp(CO) 2FeSn· (CH 2CMe 2Ph) 3 was additionally characterized by X ray crystal structure analysis. The results of the elemental analyses are in good agreement with the theoretical values. The IR spectra show the existence of η 5 2,4 cyclopentadien 1 yl, carbonyl and methyl groups in the title complexes. The above experimental results show that the M-M bond exists in Cp(CO) 2FeSn· (CH 2Me 2Ph) 3, while the existence of the M-M bond in Cp(CO) 2FeTiCp 2Cl is highly possible, too. Both the two complexes are rather stable towards air and moisture, easily soluble in tetrahydrofuran and toluene, while their solubilities are greatly different in n hexane.

关键词： Metal metal bond Heteronuclear bimetallic complex Synthesis Characterization Crystal structure

Microstructure evolution and thermal physical properties of CuCr alloy after high pressure treatment

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Rare Metals 2014年第3期33卷 293-298页

作者： Yu-Quan ma Hong-ju Lin dong-dong SongMechanical and Electrical Engineering College Hebei Normal University of Science and Technology

The thermal diffusion coefficient, thermal conductivity, and thermal expansion coefficient of CuCr alloy prepared by infiltration were measured by thermal constant tester and dilatometer before and after high pressure heat treatment, at the same time, the effect of high pressure treatment on the thermal physical properties of CuCr alloy was discussed by the analysis of its microstructure. The experimental results show that high pressure heat treatment can increase the thermal diffusion coefficient and thermal conductivity of CuCr alloy, but it changes slightly in the pressure range of 1-6 GPa. As for thermal expansion coefficient, when the temperature is higher than 130 °C, it is obviously higher than that of the alloy without high pressure treatment after 1 GPa pressure treatment, and the higher the temperature is, the larger their differences are.

关键词： CuCr alloy High pressure treatment Thermaldiffusion coefficient Thermal conductivity Thermalexpansion coefficient

Trustworthy Service Selection Integrating Cloud Model and Possibility Degree Ranking of Interval Numbers

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Chinese Journal of Electronics 2017年第6期26卷 1177-1183页

作者： ma hua HU Zhigang CAI Meiling School of Software Central South University Computer Education Department Hunan Normal University

It has been challenging to select suitable services from abundant candidates in cloud *** to the characteristics of batch computing mode and stream computing mode, a novel trustworthy service selection approach is proposed integrating cloud model and interval numbers theory. To facilitate potential users to understand the quality of service, the trustworthiness of service is described with interval number using reverse cloud generator, and the services with poor performance are filtered out by employing deviation degree or proximity degree. Two formulas of possibility degree of interval numbers are designed to compare the trustworthiness values between cloud services by utilizing probability zone analysis and geometrical analysis respectively, and the ranking method for possibility degree of interval numbers is exploited to select the most trustworthy service. The experiments show that this approach is effective to improve the accuracy of service selection and select trustworthy service for potential users in cloud paradigm.

关键词： Service selection Trustworthiness Cloud model Possibility degree ranking Interval numbers

Integration of Electrical Properties and Polarization Loss Modulation on Atomic Fe–N‑RGO for Boosting Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第2期17卷 517-532页

作者： Kaili Zhang Yuefeng Yan Zhen Wang Guansheng ma Dechang Jia Xiaoxiao huang Yu Zhou State Key Laboratory of Precision Welding&Joining of materials and Structures Harbin Institute of TechnologyHarbin 150001People’s Republic of China School of materials Science and Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China MIIT Key Laboratory of Advanced Structural‑Functional Integration materials&Green manufacturing Technology Harbin Institute of TechnologyHarbin 150001People’s Republic of China

Developing effective strategies to regulate graphene’s conduction loss and polarization has become a key to expanding its application in the electromagnetic wave absorption(EMWA)*** on the unique energy band structure of graphene,regulating its bandgap and electrical properties by introducing heteroatoms is considered a feasible ***,metal-nitrogen doping reduced graphene oxide(M–N-RGO)was prepared by embedding a series of single metal atoms M–N_(4) sites(M=Mn,Fe,Co,Ni,Cu,Zn,Nb,Cd,and Sn)in RGO using an N-coordination atom-assisted *** composites had adjustable conductivity and polarization to optimize dielectric loss and impedance matching for efficient EMWA *** results showed that the minimum reflection loss(RL_(min))of Fe–N-RGO reaches−74.05 dB(2.0 mm)and the maximum effective absorption bandwidth(EAB_(max))is 7.05 GHz(1.89 mm)even with a low filler loading of only 1 wt%.Combined with X-ray absorption spectra(XAFS),atomic force microscopy,and density functional theory calculation analysis,the Fe–N_(4) can be used as the polarization center to increase dipole polarization,interface polarization and defect-induced polarization due to d-p orbital hybridization and structural ***,electron migration within the Fe further leads to conduction loss,thereby synergistically promoting energy *** study demonstrates the effectiveness of metal-nitrogen doping in regulating the graphene′s dielectric properties,which provides an important basis for further investigation of the loss mechanism.

关键词： Electromagnetic wave absorption Fe-N-RGO Dipole polarization Conduction loss Impedance matching

Inhibition of the cGAS–STING pathway:contributing to the treatment of cerebral ischemia-reperfusion injury

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Neural Regeneration Research 2025年第7期20卷 1900-1918页

作者： Hang Yang Yulei Xia Yue ma Mingtong Gao Shuai Hou Shanshan Xu Yanqiang Wang School of Clinical Medicine Shandong Second Medical UniversityWeifangShandong ProvinceChina Department of Emergency The Affiliated Hospital of Weifang Medical UniversityWeifangShandong ProvinceChina Department of Neurology Ⅱ The Affiliated Hospital of Weifang Medical UniversityWeifangShandong ProvinceChina

The cGAS–STING pathway plays an important role in ischemia-reperfusion injury in the heart,liver,brain,and kidney,but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically ***,we outline the components of the cGAS–STING pathway and then analyze its role in autophagy,ferroptosis,cellular pyroptosis,disequilibrium of calcium homeostasis,inflammatory responses,disruption of the blood–brain barrier,microglia transformation,and complement system activation following cerebral ischemia-reperfusion *** further analyze the value of cGAS–STING pathway inhibitors in the treatment of cerebral ischemia-reperfusion injury and conclude that the pathway can regulate cerebral ischemia-reperfusion injury through multiple *** of the cGAS–STING pathway may be helpful in the treatment of cerebral ischemia-reperfusion injury.

关键词： calcium homeostasis cellular autophagy cerebral ischemia-reperfusion injury cGAS–STING pathway ferroptosis gut–brain–microbiota axis inflammatory light chain 3 microglial cells Syntaxin-17 protein

Occupancy of rooms in urban residential buildings by users in cold areas of China

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Building Simulation 2023年第3期16卷 483-497页

作者： Qi dong Zikai ma Cheng Sun School of Architecture Harbin Institute of TechnologyHarbin 150006China Key Laboratory of Cold Region Urban and Rural Human Settlement Environment Science and Technology Ministry of Industry and Information TechnologyHarbin 150006China

Occupancy is used to represent the movements and locations of users among various zones of buildings,and it is the basis of all other daily energy consumption *** study investigated eight families in cold areas of China based on occupancy measurements obtained in four main rooms,i.e.,living room,bedroom,kitchen,and *** particular,we analyzed the duration of user occupancy and hourly mean occupancy,and characterized their regular and random *** to the results,we developed an event-based occupancy model using an inhomogeneous markov chain,where the rooms were modeled and daily events were divided into three categories according to their *** established a new method for conversion between event characteristic parameters and a transition probability matrix,as well as an overlap avoidance method for active *** model was then validated using real *** results showed that the model performed well in terms of two evaluation *** model should improve the accuracy of simulations of occupancy.

关键词： event occupancy urban residential building simulation cold areas of China

Gas-liquid mass transfer in the gas-liquid-solid mini fluidized beds

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Particuology 2022年第10期20卷 22-30页

作者： Tingting dong Yongli ma Mingyan Liu School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China State Key Laboratory of Chemical Engineering(Tianjin University) Tianjin UniversityTianjin 300350China

The gas-liquid-solid mini fluidized bed(GLSMFB)combines the advantages of fluidized bed and micro-reactor,and meets the requirements for safety and efficiency of green development of process ***,there are few studies on its flow performance and no studies on its mass and heat transfer *** this paper,the characteristics of gas-liquid mass transfer in a GLSMFB were studied in order to provide basic guidance for the study of GLSMFB reaction performance and *** CO_(2)absorption by NaOH as the model process,the gas-liquid mass transfer performance of GLSMFB was *** results show that the liquid volumetric mass transfer coefficient and the gas-liquid interfacial area both increase with the increase of the superficial gas velocity within the experimental parameter range under the same given superficial liquid *** the same ratio of superficial gas to liquid velocity,the liquid volumetric mass transfer coefficient increases with the increase of the super-ficial liquid *** solid particles strengthen the liquid mass transfer process,and the liquid volumetric mass transfer coefficient is about 13%higher than that of gas-liquid mini bubble column.

关键词： Gas-liquid-solid Mini fluidized bed mass transfer coefficient Mini bubble column

Robust load-balanced backbone-based multicast routing in mobile opportunistic networks

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Frontiers of Computer Science 2023年第4期17卷 109-125页

作者： Di ZHANG dong ZHAO uadong ma Beijing Key Laboratory of Intelligent Telecommunications Software and Multimedia Beijing University of Posts and TelecommunicationsBeijing 100876China

Mobile opportunistic network(MON)is an efficient way of communication when there is no persistent connection between *** in MONs can be used to efficiently deliver messages to multiple destination ***,because multiple destination nodes are involved,multicast routing is more complex than unicast and brings a higher communication ***-based routing can effectively reduce the network overhead and the complexity of routing ***,the load of backbone nodes is larger than that of regular *** the backbone node’s buffer is exhausted,it will have a significant impact on the performance of the routing *** balancing can improve the ability of backbone to deal with the change of network load,and backbone maintenance algorithm can provide backbone *** this paper,we propose a robust load-balanced backbone-based multicast routing scheme in *** the backbone construction algorithm,we transform the problem of backbone construction into a multi-objective optimization problem,and propose a multi-objective evolutionary algorithmbased backbone construction algorithm,namely LBMBCMOEA *** addition,in order to increase the robustness of the backbone-based routing scheme,we propose a localized multicast backbone maintenance algorithm(MBma)to deal with the buffer exhaustion of backbone *** a backbone node’s residual buffer is insufficient,MBma algorithm selects other nodes to replace the backbone *** results on extensive simulations show that when considering the node buffer size constraints,compared with previous backbone-based multicast routing schemes,our proposed algorithm has better performance,and when the node’s residual buffer is insufficient,MBma algorithm can significantly improve the performance of the backbone-based multicast routing scheme.

关键词： mobile opportunistic network multicast multiobjective optimization backbone construction backbone maintenance

A PROJECTION METHOD WITH REGULARIZATION FOR THE CAUCHY PROBLEM OF THE HELMHOLTZ EQUATION

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Journal of Computational mathematics 2012年第2期30卷 157-176页

作者： Yunyun ma Fuming ma Heping dong School of mathematics Jilin UniversityChangchun 130012China

This paper is concerned with the reconstruction of the radiation wave field in the exterior of a bounded two- or three-dimensional domain from the knowledge of Cauchy data on a part of the boundary of the aforementioned domain. It is described by the Cauchy problem for the Helmholtz equation. By using the Dirichlet-to-Neumann map, this problem is transformed into an operator equation with compact operator. We rigorously justify the asymptotic behaviors of singular values of the compact operator. Then a projection method with regularization is applied to solve the operator equation, and the convergence of the regularization method is discussed. Finally, several numerical examples are presented to illustrate the approach. The results demonstrate that the algorithm is *** subject classification： 35R25, 35R30, 78A40.

关键词： Helmholtz equation Cauchy Problem Projection method Regularization.

基于离散元法的水泥稳定碎石微裂细观机理研究

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土木与环境工程学报（中英文） 2025年第1期47卷 196-204页

作者：刘子龙马士宾贺苗梁栋牛宗岳河北工业大学土木与交通学院天津300401

为探究水泥稳定碎石微裂细观演化机理,构建了细观非均质水泥稳定碎石数值模型,结合室内无侧限抗压强度试验和单轴压缩数值试验反演出模型细观参数,引入微裂隙网络研究不同裂隙参数对微裂程度的影响,分析不同裂隙数目下系统能量演化规律... 详细信息

为探究水泥稳定碎石微裂细观演化机理,构建了细观非均质水泥稳定碎石数值模型,结合室内无侧限抗压强度试验和单轴压缩数值试验反演出模型细观参数,引入微裂隙网络研究不同裂隙参数对微裂程度的影响,分析不同裂隙数目下系统能量演化规律。结果表明:数值模拟与室内试验结果基本吻合,构建的水泥稳定碎石离散元模型可较为准确地表征材料细观破坏特征;微裂损伤是二次振动加载后裂隙宽度增大和裂隙数目增多共同作用的结果,裂隙密度对水泥稳定碎石微裂程度起决定性作用;裂隙密度增加,材料储存弹性应变能的能力减弱,峰值点水泥稳定碎石材料的输入总能量降低。验证了早期微裂对于降低收缩应力的积极作用,揭示了水泥稳定碎石材料微裂力学特征和细观机理。

关键词：水泥稳定碎石无侧限抗压强度离散元法微裂技术细观机理

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