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Tungsten 2025年第1期7卷 80-87页

作者： Fang-Qian Wang Yin Zhang Wei-Wei Wang Mei-Qian Fu Hong-Bing Mo Wei-Dong Yu chao liu Jun Yan College of Chemistry and Chemical Engineering Central South University Junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

关键词： Arsenic CO2 conversion Oxazolidinone Polyoxometalates Vanadium

土基模量对水泥混凝土路面轮载疲劳开裂损伤的影响

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交通运输工程学报 2017年第2期17卷 31-40页

作者：吴玉蒋鑫吴朝阳刘竹君邱延峻西南交通大学土木工程学院四川成都610031 西南交通大学道路工程四川省重点实验室四川成都610031 西南交通大学高速铁路线路工程教育部重点实验室四川成都610031 俄克拉荷马州立大学土木与环境工程学院俄克拉荷马斯蒂尔沃特74078

基于有限元软件KENSLABS,构建了水泥混凝土路面轮载损伤计算模型,引入地基季节调整系数与零养护疲劳准则,分析了土基模量整体削弱对路面疲劳开裂指数的影响,探讨了当量轴载系数与多轴通过一次的计算次数对土基模量的依赖性,研究了不同... 详细信息

基于有限元软件KENSLABS,构建了水泥混凝土路面轮载损伤计算模型,引入地基季节调整系数与零养护疲劳准则,分析了土基模量整体削弱对路面疲劳开裂指数的影响,探讨了当量轴载系数与多轴通过一次的计算次数对土基模量的依赖性,研究了不同土基模量下板厚、水泥混凝土抗弯拉强度、单轴轴重、单轴每日重复作用次数等核心路面设计参数与路面开裂指数的关系。研究结果表明:水泥混凝土路面疲劳开裂指数随着地基季节调整系数的减小而增大,增大速度随地基季节调整系数的减小而加快,当地基季节调整系数从1.0减小为0.8和从0.4减小为0.2时,在单轴、双轴和三轴荷载作用下,路面开裂指数分别增大了2.8、2.9、1.5倍和49.8、269.0、1 351.4倍;当量轴载系数与多轴通过一次的重复计算次数受到板厚与土基模量的影响,在土基模量为60 MPa,板厚为15cm或35cm时,单轴荷载比双轴荷载更易产生损伤,双轴荷载比三轴荷载更易产生损伤,在土基模量为20MPa,板厚为15cm时也是如此,但在土基模量为20MPa,板厚为35cm时,结论则与前相反;水泥混凝土路面疲劳开裂指数随着面板厚度、水泥混凝土抗弯拉强度、单轴轴重、单轴每日重复作用次数而改变的幅度与土基模量直接相关,当土基模量为20、60 MPa时,面板厚度从21cm增加到25cm,疲劳开裂指数分别减小1.18×10、1.18×10^(-2),当混凝土抗弯拉强度从4.0 MPa增大到4.4 MPa,疲劳开裂指数分别减小1.28、2.20×10^(-3),当单轴轴重从80kN增大到160kN时,疲劳开裂指数分别增大5.48、7.36×10^(-3),当单轴荷载每日重复作用次数从50增加到90时,疲劳开裂指数分别增大2.05×10-1、5.07×10^(-4);增设厚度为15cm的水泥稳定基层后,设定工况下的路面疲劳开裂设计寿命增加3.42年;在提高土基模量的同时,宜优先考虑适当增加板厚,严禁超载,设置水泥稳定基层等措施,可以控制水泥混凝土路面受轮载作用的疲劳开裂破坏。

关键词：道路工程水泥混凝土路面零养护疲劳准则疲劳开裂损伤土基模量地基季节调整系数

Influence of rare earth doping on hydrogen absorption properties of Zr_(7)V_(5)Fe alloy

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Journal of Rare Earths 2025年第1期43卷 218-226,I0008页

作者： Shuang yang Zifeng Luo Guo yang Lijun Lv Linhua Xu Haiyan Leng Xingbo Han Jianhui Zhu Wei liu Pengfei Zhu Jing Xu School of Mathematics Physics and StatisticsShanghai University of Engineering ScienceShanghai201620China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai201800China State Key Laboratory of Advanced Special Steels&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai UniversityShanghai200444China Instrumental Analysis and Research Center Shanghai UniversityShanghai200444China

As a representative of non-evaporative getter,Zr-V-Fe has gained widespread attention due to its advantages including low activation temperatures and rapid hydrogen absorption *** this study,we investigated the impact of La and Ce doping on the thermodynamic,kinetic,and activation properties of Zr_(7)V_(5)Fe alloy.X-ray diffraction analysis shows that rare earth doping causes a decrease in the cell volume of both the ZrV_(2) andα-Zr phases of Zr_(7)V_(5)Fe alloy,which results in an increase in the plateau pressure of the *** kinetic curves illustrate that rare earth doping leads to a coarseα-Zr phases and a larger particle size after activation,resulting in a decrease in the hydrogen absorption kinetic *** for the activation process,the rare earth doped alloys exhibit excellent activation with shorter incubation periods.X-ray photoelectron spectroscopy investigations reveal that Zr and V are initially in a highly oxidized *** the heating temperature increases,they undergo a transition from oxidation state to metal *** content of metal Zr in rare earth doped alloys is higher than that in undoped alloys at 250℃,primarily due to rare earth elements'affinity for oxygen.

关键词： Rare earths Hydrogen absorption thermodynamics X-rayphotoelectron spectroscopy Activation

Study on the Fluid-Solid Coupling Seepage of the Deep Tight Reservoir Based on 3D Digital Core Modeling

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Energy Engineering 2025年第2期122卷 537-560页

作者： Haijun yang Zhenzhong Cai Hui Zhang Chong Sun Jing Li Xiaoyu Meng Chen liu Chengqiang yang PetroChina Tarim Oilfield Company Korla841000China CNPC R&D Center for Ultra-Deep Complex Reservoir Exploration and Development Korla841000China National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580China Structure and Shipping Department Offshore Oil Engineering(Qingdao)Co.Ltd.Qingdao266520China

Deep tight reservoirs exhibit complex stress and seepage fields due to varying pore structures,thus the seepage characteristics are significant for enhancing oil *** study conducted triaxial compression and permeability tests to investigate the mechanical and seepage properties of tight sandstone.A digital core of tight sandstone was built using Computed Tomography(CT)scanning,which was divided into matrix and pore phases by a pore equivalent diameter threshold.A fluid-solid coupling model was established to investigate the seepage characteristics at *** results showed that increasing the confining pressure decreased porosity,permeability,and flow velocity,with the pore phase becoming the dominant seepage *** and large pores closed first under increasing pressure,resulted in a steep drop in ***,permeability slightly decreased under high confining pressure,which followed a first-order exponential *** velocity increased with seepage *** the damage mainly occurred in stress-concentration regions under low seepage *** behavior followed linear Darcy flow,the damage emerged at seepage entrances under high pressure,which decreased rock elastic modulus and significantly increased permeability.

关键词： Digital core fluid-solid coupling pore structure microscopic seepage

Visible-light-driven four-component diacylation of styrenes with acyl azolium salts:carbonylative synthesis of 1,4-diketones

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Science China Chemistry 2025年

作者： Maolin yang Yukun liu Peng yang Yanhua Zhao Xiaofeng Wu Leibniz-Institut für Katalyse e.V. Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of Sciences

A photochemically induced carbon monoxide-inclusive four-component carbonylation reaction has been delineated,facilitating the diacylation of styrenes with acyl azolium salts to synthesize valuable 1,4-diketone compounds with moderate to good *** process proceeds by generating acyl radicals from the Hantzsch esters and carbon monoxide,which subsequently add to the terminal position of ***,under light irradiation,the newly generated carbon radical can further react with activated acyl azolium salts to finish the desired 1,4-diketone products.

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Preparation and Performance of Ternary Early Strength Agent and Quercetin Composite Cement Sealing Material

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 130-140页

作者： liu Jian CHEN Meiting JI Xiaoli XU chao WANG Chunmei Department of Safety Science and Engineering Anhui University of Science and TechnologyHuainan 232001China Key Laboratory of Mine Safety and High Efficient Mining Jointly Built by Province and Education Ministry Anhui University of Science and TechnologyHuainan 232001China Department of Chemical Engineering and Explosives Anhui University of Science and TechnologyHuainan 232001China

A ternary early-strengthening agent consisting of calcium formate+triethanolamine+lithium sulfate was compounded with quercetin to shorten the setting time of cementitious materials while ensuring their early *** optimum ratio of the three early-strengthening agents was determined as 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate by response surface *** effects of the ternary early-strengthening agent composed of calcium formate+triethanolamine(TEA)+lithium sulfate on cementitious pore sealing materials under the synergistic effect of quercetin were studied by means of the performance tests of compressive strength,fluidity,and setting time,and the microstructural characterizations of X-ray powder diffractometer(XRD),thermogravimetry(TG-DSC)and scanning electron microscopy(SEM).The study shows that the synergistic effect of ternary early-strengthening agent and quercetin forms a multi-performance composite admixture for cementitious *** best performance was obtained with the compounding scheme of 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate ternary early-strengthening agent and 0.05%*** compressive strength of 1,3,7,and 28 d are 94.8%,39.8%,42%,and 28%higher than those of the blank group,*** initial time and final setting time are 41 and 57 minutes,*** to the microscopic analysis,the network and fibrous C-S-H gels generated by ternary early-strengthening agents are attached to the surface promoted by quercetin,which forms skeleton support while thickening and solidifying the cement slurry,which enhances the early compressive strength of the cement-based materials.

关键词： sealing material ternary early-strengthening agent quercetin synergetic effect response surface methodology

Targeting vulnerable microcircuits in the ventral hippocampus of male transgenic mice to rescue Alzheimer‑like social memory loss

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Military Medical Research 2025年第1期12卷 48-71页

作者： Hui-yang Lei Gui-Lin Pi Ting He Rui Xiong Jing-Ru Lv Jia-Le liu Dong-Qin Wu Meng-Zhu Li Kun Shi Shi-Hong Li Na-Na Yu yang Gao Hui-Ling Yu Lin-Yu Wei Xin Wang Qiu-Zhi Zhou Pei-Lin Zou Jia-yang Zhou Ying-Zhou liu Nai-Ting Shen Jie yang Dan Ke Qun Wang Gong-Ping liu Xi-Fei yang Jian-Zhi Wang Ying yang Department of Pathophysiology School of Basic MedicineKey Laboratory of Education Ministry of China/Hubei Province for Neurological DisordersTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Traditional Chinese Medicine the Central Hospital of WuhanTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430014China Key Laboratory of Modern Toxicology of Shenzhen Shenzhen Center for Disease Control and PreventionShenzhen 518055GuangdongChina Co‑Innovation Center of Neuroregeneration Nantong UniversityNantong 226000JiangsuChina

Background:Episodic memory loss is a prominent clinical manifestation of Alzheimer’s disease(AD),which is closely related to tau pathology and hippocampal *** to the heterogeneity of brain neurons,the specific roles of different brain neurons in terms of their sensitivity to tau accumulation and their contribution to AD-like social memory loss remain ***,further investigation is ***:We investigated the effects of AD-like tau pathology by Tandem mass tag proteomic and phosphoproteomic analysis,social behavioural tests,hippocampal electrophysiology,immunofluorescence staining and in vivo optical fibre recording of GCaMP6f and ***,we utilized optogenetics and administered ursolic acid(UA)via oral gavage to examine the effects of these agents on social memory in ***:The results of proteomic and phosphoproteomic analyses revealed the characteristics of ventral hippocampal CA1(vCA1)under both physiological conditions and AD-like tau *** tau progressively accumulated,vCA1,especially its excitatory and parvalbumin(PV)neurons,were fully filled with mislocated and phosphorylated tau(p-Tau).This finding was not observed for dorsal hippocampal CA1(dCA1).The overexpression of human tau(hTau)in excitatory and PV neurons mimicked AD-like tau accumulation,significantly inhibited neuronal excitability and suppressed distinct discrimination-associated firings of these neurons within *** excitatory and PV neurons in vCA1 at specific rhythms and time windows efficiently ameliorated tau-impaired social ***,1 month of UA administration efficiently decreased tau accumulation via autophagy in a transcription factor EB(TFEB)-dependent manner and restored the vCA1 microcircuit to ameliorate tau-impaired social ***:This study elucidated distinct protein and phosphoprotein networks between dCA1 and vCA1 and highlighted the susceptibility of the vCA1 microcircuit to AD-like tau

关键词： Alzheimer’s disease Tau protein Ventral hippocampus Social memory Ursolic acid Transcription factor EB(TFEB)

Nanograting‑Based Dynamic Structural Colors Using Heterogeneous Materials

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Nano-Micro Letters 2025年第3期17卷 138-151页

作者： Jingang Wang Haibo Yu Jianchen Zheng Yuzhao Zhang Hongji Guo Ye Qiu Xiaoduo Wang Yongliang yang Lianqing liu State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Dynamic structuralcolors can change in response todifferent environmental *** ability remains effectiveeven when the size of the speciesresponsible for the structural coloris reduced to a few micrometers,providing a promising sensingmechanism for solving microenvironmentalsensing problems inmicro-robotics and ***, the lack of dynamicstructural colors that can encoderapidly, easily integrate, and accuratelyreflect changes in physical quantities hinders their use in microscale sensing applications. Herein, we present a 2.5-dimensionaldynamic structural color based on nanogratings of heterogeneous materials, which were obtained by interweaving a pH-responsive hydrogelwith an IP-L photoresist. Transverse gratings printed with pH-responsive hydrogels elongated the period of longitudinal grating in the swollenstate, resulting in pH-tuned structural colors at a 45° incidence. Moreover, the patterned encoding and array printing of dynamic structuralcolors were achieved using grayscale stripe images to accurately encode the periods and heights of the nanogrid structures. Overall, dynamicstructural color networks exhibit promising potential for applications in information encryption and in situ sensing for microfluidic chips.

关键词： Dynamic structural colors Four-dimensional printing pH-responsive Nanogrid Heterogeneous materials

Localizing base stations with measured data:a concatenated image-based deep learning approach

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Science China(Information Sciences) 2025年第2期68卷 385-386页

作者： yang CHEN Ziyuan liu Feng JIANG Hong SHEN Wei XU Mengyu LI Ritao CHENG National Mobile Communications Research Laboratory Southeast University China Mobile Group Design Institute Co. Ltd.

Localization has become an indispensable function of modern cellular communication systems [1]. In a cloud radio access network(C-RAN), the remote radio head(RRH) is the actual signal transmitter, whose location can assist in wireless network layout optimization and wireless resource management. The measurement of the RRH location can only be done manually on-site due to the lack of global positioning systems(GPS) at the RRH side, which is thus not a cost-effective solution for the widely used C-RAN with a large number of RRH units.

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Efficient propane dehydrogenation catalyzed by Ru nanoparticles anchored on a porous nitrogen-doped carbon matrix

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Chinese Chemical Letters 2025年第2期36卷 230-233页

作者： Tianyi yang Fangxi Su Dehuan Shi Shenghong Zhong Yalin Guo Zhaohui liu Jianfeng Huang State Key Laboratory of Coal Mine Disaster Dynamics and Control Institute of Advanced Interdisciplinary StudiesSchool of Chemistry and Chemical EngineeringChongqing University Key Laboratory of Advanced Materials Technologies International (HongKong Macao and Taiwan) Joint Laboratory on Advanced Materials TechnologiesCollege of Materials Science and EngineeringFuzhou University

Propane dehydrogenation （PDH） is a vital industrial process for producing propene,utilizing primarily Cr-based or Pt-based *** catalysts often suffer from challenges such as the toxicity of Cr,the high costs of noble metals like Pt,and deactivation issues due to sintering or coke formation at elevated *** introduce an exceptional Ru-based catalyst,Ru nanoparticles anchored on a nitrogendoped carbon matrix （Ru@NC）,which achieves a propane conversion rate of 32.2%and a propene selectivity of 93.1%at 550°C,with minimal coke deposition and a low deactivation rate of 0.0065 *** using techniques like TEM and XPS,along with carefully-designed controlled experiments,reveal that the notable performance of Ru@NC stems from the modified electronic state of Ru by nitrogen dopant and the microporous nature of the matrix,positioning it as a top contender among state-of-the-art PDH catalysts.

关键词： Electronic interaction Porous carbon matrix Propane dehydrogenation Ru nanoparticles Ru@NC