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Journal of Magnesium and Alloys 2021年第5期9卷 1649-1660页

作者： J.Wang T.li H.X.li Y.Z.Ma K.N.Zhao c.l.yang J.S.Zhang State Key laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Department of Petroleum Equipment of RIPED PetroChinaBeijing 100083China State Key laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China

Magnesium alloys,a novel functional material for the fabrication of fracturing tools,are being paid more and more attentions recently due to their relatively high mechanical properties and fast dissolubility ability after *** this study,the novel extruded Mg-10Gd-3Y-0.3Zr-xNi alloys will be reported and their microstructure,mechanical and corrosion behaviors will be also *** results show that Ni contents influence phase precipitation *** adding 0.2 wt%Ni,a large amount of Zr_(7)Ni_(10)phases will be precipitated insidesα-Mg matrix,directly leading to degradation of strength and large corrosion *** further increasing Ni contents,the precipitation phases can be changed from Mg_(5)RE to 18R-lPSO structure,resulting in higher mechanical properties and faster corrosion ***,adding Ni element also change the texture orientation by influencing the precipitation behavior of the *** alloys invented in this paper have attained the highest compressive and tensile properties among all the reported dissoluble magnesium *** work is beneficial in understanding the role of Ni in the magnesium alloys and provides more materials alternatives for the fabrication of dissoluble fracturing tools.

关键词： Dissoluble magnesium alloys Microstructure Mechanical properties corrosion behaviors Fracturing tools

Effects of dealloying and heat treatment parameters on microstructures of nanoporous Pd

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Journal of Materials Science & Technology 2020年第13期47卷 123-129页

作者： Y.Z.chen X.Y.Ma W.X.Zhang H.Dong G.B.Shan Y.B.cong c.li c.l.yang F.liu State Key lab.of Solidification Processing Northwestern Polytechnical University710072 Xi’anChina

Microstructures of nanoporous Pd are essentially important for its physical and chemical *** this work,we show that the microstructures of nanoporous Pd can be tuned by adjusting compositions of the precursor alloys,and dealloying and heat treatment *** the ligament and pore sizes decrease with increasing the electrochemical potential upon dealloying and the concentration of noble component in the precursor *** treatment causes coarsening of the nanoporous *** a critical temperature,the nanoporous structures are subjected to significant *** the critical temperature,surface diffusion is believed to dominate the coarsening *** the critical temperature,the nanoporous structure coarsens remarkably at a rather high rate,which is ascribed to a multiple-mechanism controlled process.

关键词： Nanoporous metals Microstructure Dealloying Kinetics coarsening

分子束外延生长ZnSe自组织量子点光、电行为研究

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物理学报 2002年第2期51卷 310-314页

作者：卢励吾王占国 c.l.yang J.Wang Z.H.Ma I.K.Sou Weikun Ge 中国科学院半导体研究所半导体材料科学开放实验室北京100083 香港科技大学物理系

分别应用光致发光、电容电压和深能级瞬态傅里叶谱技术详细研究ZnSe自组织量子点样品的光学和电学行为 .光致发光温度关系表明ZnSe量子点的光致发光热猝火过程机理 .两步猝火过程的理论较好模拟和解释了相关的实验数据 .电容电压测... 详细信息

分别应用光致发光、电容电压和深能级瞬态傅里叶谱技术详细研究ZnSe自组织量子点样品的光学和电学行为 .光致发光温度关系表明ZnSe量子点的光致发光热猝火过程机理 .两步猝火过程的理论较好模拟和解释了相关的实验数据 .电容电压测量表明样品表观载流子积累峰出现的深度 (样品表面下约 10 0nm处 )大约是ZnSe量子点层的位置 .深能级瞬态傅里叶谱获得的ZnSe量子点电子基态能级位置为ZnSe导带下的 0 11eV ,这与ZnSe量子点光致发光热猝火模型得到的结果一致 .

关键词： Ⅱ-Ⅵ半导体自组织量子点 ZnSe 分子束外延生长光学特性电学特性硒化锌

Spalling characteristics of high-temperature treated granitic rock at different strain rates

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1280-1288页

作者： l.F.Fan Q.H.yang X.l.Du The Key laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing100124China

The dynamic spalling characteristics of rock are important for stability analysis in rock *** paper presented an experimental investigation on the dynamic spalling characteristics of granite with different temperatures and strain rates.A series of dynamic spalling tests with different impact velocities were conducted on thermally treated granite at different *** dynamic spalling strengths of granite with different temperatures and strain rates were determined.A model was proposed to correlate the dynamic spalling strength of granite,high temperature and strain *** results show that the spalling strength of granite decreases with increasing ***,the spalling strength of granite with a higher strain rate is larger than that with a lower strain *** proposed model can describe the relationship among dynamic spalling strength of granite,high temperature and strain rate.

关键词： Dynamic spalling characteristics High temperature Strain rate Dynamic loading Granite

Application of Gaussian Beam Summation Migration in Reflected In-seam Wave Imaging

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 276-284页

作者： HAN Jianguang lÜQingtian ZHANG Zhiheng yang Shun WANG Shuo chinese Academy of Geological Sciences Beijing 100037China Shandong Taishan Resources Exploration co. Ltd.Jinan 250104China

The geological conditions for coal mining in china are complex,with various structural issues such as faults and collapsed columns seriously compromising the safety of coal mine ***-seam wave exploration is an effective technique for acquiring detailed information on geological structures in coal seam working ***,the existing reflected in-seam wave imaging technique can no longer meet the exploration precision requirements,making it imperative to develop a new reflected in-seam wave imaging *** study applies the Gaussian beam summation(GBS)migration method to imaging coal seams'reflected in-seam wave ***,with regard to the characteristics of the reflected in-seam wave data,methods such as wavefield removal and enveloped superposition are employed for the corresponding wavefield separation,wave train compression and other processing of reflected in-seam ***,imaging is performed using the GBS migration *** feasibility and effectiveness of the proposed method for reflected in-seam wave imaging are validated by conducting GBS migration tests on 3D coal-seam fault models with different dip angles and *** applying the method to reflected in-seam wave data for an actual coal seam working face,accurate imaging of a fault structure is obtained,thereby validating its practicality.

关键词： reflected in-seam wave Gaussian beam summation migration numerical tests fault

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： c.Y.Morassuti A.P.l Silva l.A.O.Nunes S.M.lima l.H.c.Andrade Optical and Photothermal Spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

Spatiotemporal Evaluation and Future Projection of Diurnal Temperature Range over the Tibetan Plateau in cMIP6 Models

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Advances in Atmospheric Sciences 2024年第11期41卷 2245-2258页

作者： Suguo ZHANG Qin HU Xianhong MENG Yaqiong lÜ Xianyu yang School of Atmospheric Sciences/Plateau Atmosphere and Environment Key laboratory of Sichuan Province Chengdu University of Information TechnologyChengdu 610225China Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China School of Atmospheric Sciences Sun Yat-sen UniversityZhuhai 519082China Earth System Modelling School of Engineering and DesignTechnical University of MunichMunich 85521Germany

The diurnal temperature range(DTR) serves as a vital indicator reflecting both natural climate variability and anthropogenic climate change. This study investigates the historical and projected multitemporal DTR variations over the Tibetan Plateau. It assesses 23 climate models from phase 6 of the coupled Model Intercomparison Project(cMIP6) using cN05.1 observational data as validation, evaluating their ability to simulate DTR over the Tibetan Plateau. Then, the evolution of DTR over the Tibetan Plateau under different shared socioeconomic pathway(SSP) scenarios for the near,middle, and long term of future projection are analyzed using 11 selected robustly performing models. Key findings reveal:(1) Among the models examined, Bcc-cSM2-MR, Ec-Earth3, Ec-Earth3-cc, Ec-Earth3-Veg, Ec-Earth3-Veg-lR,FGOAlS-g3, FIO-ESM-2-0, GFDl-ESM4, MPI-ESM1-2-HR, MPI-ESM1-2-lR, and INM-cM5-0 exhibit superior integrated simulation capability for capturing the spatiotemporal variability of DTR over the Tibetan Plateau.(2) Projection indicates a slightly increasing trend in DTR on the Tibetan Plateau in the SSP1-2.6 scenario, and decreasing trends in the SSP2-4.5, SSP3-7.0, and SPP5-8.5 scenarios. In certain areas, such as the southeastern edge of the Tibetan Plateau, western hinterland of the Tibetan Plateau, southern Kunlun, and the Qaidam basins, the changes in DTR are relatively large.(3) Notably, the warming rate of maximum temperature under SSP2-4.5, SSP3-7.0, and SPP5-8.5 is slower compared to that of minimum temperature, and it emerges as the primary contributor to the projected decrease in DTR over the Tibetan Plateau in the future.

关键词： Tibetan Plateau cMIP6 models diurnal temperature range model assessment historical period future projection

Vibration properties of Paulownia wood for Ruan sound quality using machine learning methods

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Journal of Forestry Research 2024年第5期35卷 216-222页

作者： yang yang college of Art and Design Harbin UniversityHarbin 150076People’s Republic of China college of Mechanical and Electrical Engineering Northeast Forestry UniversityHarbin 150040People’s Republic of China

As an important material for manufacturing resonant components of musical instruments,Paulownia has an important influence on the sound quality of *** this paper,a model for evaluating the sound quality of Ruan based on the vibration characteristics of wood is developed using machine learning ***,the selection of materials for Ruan manufacturing relies primarily on manually weighing,observing,striking,and listening by the instrument *** in scientific theory have hindered the quality of the finished *** this study,nine Ruans were manufactured,and a prediction model of Ruan sound quality was proposed based on the raw material information of *** of a total of 180 data sets,145 and 45 sets were chosen for training and validation,*** this paper,typical correlation analysis was used to determine the correlation between two single indicators in two adjacent pairwise combinations of the measured objects in each stage of the production process in *** vibra-tion characteristics of the wood were tested,and a model for predicting the evaluation of Ruan’s acoustic qualities was developed by measuring the vibration characteristics of the resonating plate *** acoustic quality of the Ruan sound board wood was evaluated and predicted using machine learning model generalized regression neural *** results show that the prediction of Ruan sound quality can be achieved using Matlab simulation based on the vibration characteristics of the soundboard *** the model-predicted values were compared with the tradi-tional predicted results,it was found that the generalized regression neural network had good performance,achieving an accuracy of 93.8%which was highly consistent with the experimental *** was concluded that the model can accurately predict the acoustic quality of the Ruan based on the vibration performance of the soundboards.

关键词： Sound quality Wood vibration performance Paulownia wood Machine learning methods

High-efficiency carbonation Modification Methods of Recycled coarse Aggregates

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 386-398页

作者：张美香 yang Xiaolin 丁亚红 SUN Bo ZHANG Xianggang lÜXiuwen Department of civil Engineering Henan Polytechnic UniversityJiaozuo 454150China college of Architectural Engineering Xinyu UniversityXinyu 336500China

To solve the problem of only surface carbonation and realize high-efficiency carbonation of recycled coarse aggregate,the method of carbonated recycled coarse aggregate with nano materials pre-soaking was first put *** carbonation effect of modified recycled coarse aggregate with three different carbonation methods was evaluated,and water absorption,apparent density and crush index of modified recycled coarse aggregate were *** with XRD,SEM,and MIP microscopic analysis,the high-efficiency carbonation strengthening mechanism of modified recycled coarse aggregate was *** experimental results show that,compared with the non-carbonated recycled coarse aggregate,the physical and microscopic properties of carbonated recycled coarse aggregate are *** method of carbonation with nano-SiO_(2) pre-soaking can realize the high-efficiency carbonation of recycled coarse aggregate,for modified recycled coarse aggregate with the method,water absorption is reduced by 23.03%,porosity is reduced by 44.06%,and the average pore diameter is 21.82 *** high-efficiency carbonation strengthening mechanism show that the pre-socked nano-SiO_(2) is bound to the hydration product ca(OH)_(2) of the old mortar with nano-scale c-S-H,which can improve the cO_(2) absorption rate,accelerate the carbonation reaction,generate more stable cacO_(3) and nano-scale silica gel,and bond to the dense three-dimensional network structure to realize the bidirectional enhancement of nano-materials and pressurized *** is concluded that the method of carbonation with nano-SiO_(2) pre-soaking is a novel high-efficiency carbonation modification of recycled coarse aggregate.

关键词： recycled coarse aggregate pressurized carbonation high-efficiency carbonation nano-SiO2 strengthening mechanism

Nonaqueous potassium-ion full-cells:Mapping the progress and identifying missing puzzle pieces

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Journal of Energy chemistry 2024年第6期93卷 384-399,I0010页

作者： Badre larhrib louiza larbi lénaïc Madec Universite de Pau et des Pays de l’Adour E2S UPPACNRSIPREMPauFrance Universitéde Haute-Alsace Institut de Science des Matériaux de Mulhouse(IS2M)CNRS UMR 7361F-68100 MulhouseFrance Universitéde Strasbourg F-67081 StrasbourgFrance Réseau sur le Stockage Electrochimique de l’Energie CNRS FR3459AmiensFrance Institut des Matériaux Jean Rouxel(IMN) CNRS UMR 6502Univ.Nantes44322 Cedex 3 NantesFrance

This review addresses the growing interest for potassium-ion full-cells(KIFcs)in view of the transition from potassium-ion half-cells(KIHcs)toward commercial K-ion batteries(KIBs).It focuses on the key parameters of KIFcs such as the electrode/electrolyte interfaces challenge,major barriers,and recent advancements in *** strategies for enhancing KIFc performance,including interfaces co ntrol,electrolyte optimization,electrodes capacity ratio,electrode material screening and electrode design,are *** review highlights the need to evaluate KIBs in full-cell configurations as half-cell results are strongly impacted by the K metal *** also emphasizes the importance of understanding solid electrolyte interphase(SEI)formation in KIFcs and explores promising nonaqueous as well as quasiand all-solid-state electrolytes *** review thus paves the way for practical,cost-effective,and scalable KIBs as energy storage systems by offering insights and guidance for future research.

关键词： K-ion full-cells Potassium-ion batteries cross-talk Solid-state batteries Potassium reactivity Electrolyte design Electrode design