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Evolution of In783 alloy in microstructure and properties enduring different service times

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Rare Metals 2024年第1期43卷 334-341页

作者： Zhong-Shuai Han jin-Feng Du jun Liang zheng Zhang School of Material Science and Engineering Beihang UniversityBeijing 100191China Shenhua Guohua(Beijing)Electric Power Research Institute Co. Ltd.Beijing 100025China

Impact, tensile, and fatigue tests were performed in In783 alloy serving 4000, 23,000 and 48,000 h. The microstructure was then analysed by optical microscopy(OM), scanning electron microscopy(SEM), and transmission electron microscopy(TEM) to probe the relationship between microstructure and properties. The results show that a new Ni_(5)Al_(3) phase is found, which grows gradually in β phase with serving time increasing,destroying the martensitic structure of the β phase, and degenerating the toughness of the β phase(approximately13.88% reduction). Therefore, the degradation of the βphase results in a sharp dropping of the resistance to stress accelerated grain boundary oxygen(SAGBO) during serving;thus, the intergranular fracture morphology degree increases with duration of service(almost 40% increase from the fractured surface). In addition, the strength of alloy will be gradually enhanced when the γ'phase becomes relatively bulky with serving time increasing due to considerable distortion of the dislocations as a result of the spacing of individual particles, in which any movement of the dislocation will have to overcome a larger number of obstacles per unit length.

关键词： In783 Microstructure Properties βphase Ni_(5)Al_(3)phase

Assessing Soil Erosion Rates on Manually-Tilled Hillslopes in the Sichuan Hilly Basin Using ^(137)Cs and ^(210)Pb_(ex) Measurements

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Pedosphere 2007年第3期17卷 273-283页

作者： zheng jin-jun HE Xiu-Bin D. WALLING ZHANG Xin-Bao D. FLANAGAN QI Yong- Qing Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 （China） Graduate University of the Chinese Academy of Sciences Beijing 100049 （China） Department of Geography University of Exeter Exeter EX4 4RJ （UK） State Key laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of SciencesXi＇an 710075 （China） USDA-ARS National Soil Erosion Research Laboratory West Lafayette Indiana 47907 （USA） Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101（China）

Purple soils are widely distributed in the Sichuan Hilly Basin and are highly susceptible to erosion, especially on the cultivated slopes. Quantitative assessment of the erosion rates is, however, difficult due to small size of the plots of the manually-tilled land, the complex land use, and steep hillslopes. ^137Cs and ^210Pbex （excess ^210Pb） tracing techniques were used to investigate the spatial pattern of soil erosion rates associated with slope-land under hoe tillage in Neijiang of the Sichuan Hilly Basin. The ^137Cs and ^210Pbex inventories at the top of the cultivated slope were extremely low, and the highest inventories were found at the bottom of the cultivated slope. By combining the erosion rates estimates provided by both ^137Cs and 21~Pbex measurements, the weighted mean net soil loss from the study slope was estimated to be 3 100 t km^-2 year^-1, which was significantly less than 6 930 t km^-2 year^-1 reported for runoff plots on a 10° cultivated slope at the Suining Station of Soil Erosion. The spatial pattern of soil erosion rates on the steep agricultural land showed that hoe tillage played an important role in soil redistribution along the slope. Also, traditional farming practices had a significant role in reducing soil loss, leading to a lower net erosion rate for the field.

关键词： ^137Cs hoe tillage, ^210Pbex purple soil soil erosion

Dynamic lithium-compensation mechanism for densification of garnet-type Li_(7)La_(3)Zr_(2)O_(12)electrolyte by Li_(2)O atmosphere buffer pair

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Nano Research 2024年第7期17卷 6184-6191页

作者： Chujun zheng Ya Chen Haoxin Dong Yan Lu jun jin Zhaoyin Wen CAS Key Laboratory of Materials for Energy Conversion Shanghai Institute of CeramicsChinese Academy of ScienceShanghai 200050China State Key Lab High Performance Ceram and Superfine Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Solid-state lithium metal batteries are one of the most promising options for next-generation batteries pursuing high-energy density and ***,the inevitable volatilization of lithium compounds during sintering leads to low relative density and low ionic conductivity of solid-state ***,the dynamic lithium-compensation mechanism is proposed to facilitate the densification of Ta-substituted garnet-type electrolyte(Li_(6.5)La_(3)Zr_(1.5)Ta_(0.5)O_(12)(LLZT))through the reversible manipulating of Li_(2)O ***_(2)ZrO_(3)is used as mother powder additive,which reacts with Li_(2)O in sintering atmosphere and forms Li_(6)Zr_(2)O_(7).Li_(2)ZrO_(3)/Li_(6)Zr_(2)O_(7)buffer pair manipulates the sintering Li_(2)O atmosphere,which is vital for LLZT,within the Li_(2)O partial pressure range corresponding to Li_(2)ZrO_(3)and Li_(6)Zr_(2)O_(7).Furthermore,the reversibility mechanism of buffer pair for Li_(2)O absorption and release is *** obtained LLZT exhibits a relative density of over 96%and an ionic conductivity exceeding 7×10^(−4)S·cm^(−1)with no abnormal grain *** symmetric cell demonstrates an excellent lithium dendrite suppressing ability(stable cycling at a current density of 0.3 mA·cm^(−2)for over 1000 h).Such dynamic lithium-compensation strategy has been successfully applied in atmosphere manipulation of LLZT sintering process,which reduces the dependence of LLZT on the Li_(2)O atmosphere,making it conducive to large-scale preparation of electrolyte ceramics.

关键词： solid-state batteries garnet-type electrolyte high-density electrolyte dynamic lithium-compensation buffer pair

Quantifying freeze-melt dynamics of lakes on the Tibetan Plateau using Sentinel-1 synthetic aperture radar imagery

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Journal of Mountain Science 2024年第3期21卷 805-819页

作者： jin Lu CHEN jun CAI Yu KONG Yecheng WANG Yongfeng DUAN zheng School of Environment and Energy Engineering Anhui Jianzhu UniversityHefei 230601China Anhui Engineering and Technology Research Center for Smart City Anhui Jianzhu UniversityHefei 230601China School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210023China Department of Physical Geography and Ecosystem Science Lund UniversityLund 22362Sweden

The ice phenology of alpine lakes on the Tibetan Plateau(TP)is a rapid and direct responder to climate changes,and the variations in lake ice exhibit high temporal frequency *** and passive microwave data are widely used to monitor lake ice changes with high temporal ***,the low spatial resolutions make it difficult to effectively quantify the freeze-melt dynamics of *** work used Sentinel-1 synthetic aperture radar(SAR)data to derive high-resolution ice maps(about 6 days),then with the aid of Sentinel-2 optical images to quantify freeze-melt processes in three typical lakes on the TP(*** Co,Ayakekumu Lake,and Nam Co).The results showed that three lakes had an average annual ice period of 125-157 days and a complete ice cover period of 72-115 days,from 2018 to *** exhibit different ice phenology *** Co is characterized by repeated episodes of freezing,melting,and refreezing,resulting in a prolonged freeze-up ***,the break-up period of Nam Co lasts for a longer duration(about 19 days),and the break-up exhibits a smooth ***,Ayakekumu Lake showed more significant inter-annual fluctuations in the freeze-up period,with deviations of up to 28 days observed among different *** to the other two lakes,Selin Co experienced a relatively short freeze-up and break-up *** short,Sentinel-1 SAR data can effectively monitor the weekly and seasonal variations in lake ice on the ***,this data facilitates quantification of the freeze-melt dynamics.

关键词： Lake ice Sentinel-1 SAR Tibetan Plateau Climate change

About the evaluation of drug combination

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Acta Pharmacologica Sinica 2004年第2期 20-21页

作者： zheng-jun jin1Department of Pharmacology, Shanghai Second Medical University, Shanghai 200025, China

An empirical model for high energy density lithium-(ion)batteries with ultra-thick electrodes

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Tungsten 2024年第1期6卷 230-237页

作者： Li-Ming jin Guang-Guang Xing Nan Qin Yan-Yan Lu jun-Sheng zheng Cun-Man Zhang Jim P.zheng School of Automotive Studies and Clean Energy Automotive Engineering Center Tongji UniversityShanghai 201804China Department of Electrical Engineering University at BuffaloThe State University of New YorkBuffaloNY 14260USA

Increasing the electrode thickness is a significant method to decrease the weight and volume ratio of the inactive components for high energy density of the *** this contribution,we extracted a repeating unit in the configurations and establish the empirical energy density model based on some *** this model,the effects of the electrode thickness on the energy density for lithium-ion batteries(LIBs),lithium metal batteries(LMBs),and anode-free lithium batteries(ALBs)are evaluated quantitively with the current parameters of the *** results demonstrate that the structure evolutions from LIBs,LMBs to ALBs with the reduction of the anode weight contribution,the energy density can be well improved *** the increase of the thickness of the electrode provide another route to furthe r enhance the energydensity by decreasing the weight contribution of inactive materials;meanwhile the effects for ALBs are higher than LMBs and LIBs due to the higher weight ratio of inactive *** empirical energy density model is also applied into the practical system and provide intuitional results to guide the battery design for higher energy density.

关键词： Empirical model High energy density Lithium batteries Ultra-thick electrodes

Investigation on the influence of vortex generator on particle resuspension

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Particuology 2024年第3期86卷 126-136页

作者： Dongchi Yu jun-Li Lin jin-Han Xie ASML 80W Tasman DrSan Jose95134CaliforniaUSA Department of Mechanics and Engineering Science at College of Engineering and State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing100081China

The vortex generator(VG)and its well-known effect in flow optimization are widely studied and employed across different engineering ***,while the same working principles of VG may be well suited for the applications on surface-cleaning technologies,such promising potential is hardly,if any,explored in the published ***,in the present study,the influence on flow-induced particle resuspension brought by a rectangular vG in a channel flow is investigated with the help of highfidelity computational fluid dynamics *** increases of particle removal forces and resuspension rates are discovered in long,strip-like regions with reduced boundary-layer thickness resulted from the vG-induced vortices,and the enhancement effect is especially significant for configurations with the VG installed at a greater angle of *** is also shown that while the resuspension enhancements on the lower and the upper surfaces of the channel exhibit distinct statistical characteristics,having a VG in the channel improves the overall particle-removing capability of the channel flow by introducing higher surface-averaged removal forces and particle resuspension *** but not least,the increase of resuspension rate is especially significant for the smaller,micron-scale particles which are otherwise hardly disturbed by a VG-less channel flow,and such resuspension-enhancement effectgenerally subsides with increasing particle size.

关键词： Particle resuspension Vortexgenerator CFD Surface cleaning

Tough Semi-interpenetrating Polyvinylpyrrolidone/Polyacrylamide Hydrogels Enabled by Bioinspired Hydrogen-bonding Induced Phase Separation

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Chinese Journal of Polymer Science 2024年第5期42卷 591-603,I0006页

作者： Qiong-jun Xu Zhao-Yang Yuan Chang-Cheng Wang Hao Liang Yu Shi Hai-Tao Wu Hu Xu jing zheng jin-Rong Wu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China

Semi-interpenetrating(semi-IPN)hydrogels formed by the continuous interpenetration of cross-linked polymer network and linear non-crosslinked polymer with multifunctionality are widely used in biomedical and other ***,the negative impact of linear polymer on the homogeneity of the cross-linked network often leads to a decrease in the mechanical properties of semi-IPN hydrogels and severely limits their ***,a bioinspired hydrogen-bonding induced phase separation strategy is presented to construct the tough semi-IPN polyvinylpyrrolidone/polyacrylamide hydrogels(named PVP/PAM hydrogels),including the linear polymer polyvinylpyrrolidone(PVP)and cross-linked polyacrylamide(PAM)*** resultant PVPx/PAM hydrogels exhibit unique phase separation induced by the hydrogen bonding between PVP and PAM and affected by the amount of substance of ***,the phase separation of PVPx/PAM hydrogels results in excellent mechanical properties with a strain of 2590%,tensile strength of 0.28 MPa and toughness of 2.17 MJ/m^(3).More importantly,the hydrogen bonding between PVP and PAM firstly disrupts to dissipate energy under external forces,so the PVPx/PAM hydrogels exhibit good self-recovery properties and outperform chemically cross-linked PAM hydrogels in impact resistance and damping *** is believed that the PVPx/PAM hydrogels with hydrogen-bonding induced phase separation possess more potential application prospects.

关键词： Tough Semi-interpenetrating networks Polyvinylpyrrolidone/polyacrylamide Hydrogels Phase separation

Revealing the Structure-Property Difference of Natural Rubber Prepared by Different Methods: Protein and Gel Content are Key Factors

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Chinese Journal of Polymer Science 2024年第4期42卷 457-467页

作者： Shao-Qi Huang jun-Qi Zhang Yong Zhu Ling-Min Kong Lu-Sheng Liao Fu-Quan Zhang zheng-Tian Xie jin-Rong Wu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China Hainan Provincial Key Laboratory of Natural Rubber Processing Agricultural Products Processing Research Institute of Chinese Academy of Tropical Agricultural SciencesZhanjiang524001China

Natural rubber (NR) is widely used in various fields including aerospace, military industry and transportation due to its superior elasticity and comprehensive mechanical properties. Nonetheless, the commercial NR prepared by different methods usually exhibits different mechanical properties, primarily due to variations in processing conditions during the conversion from latex to bulk rubber material. Consequently, this poses challenges in scientific research and industrial production of NR. In order to assess the properties of various commercially available NR and identify key structural and compositional components, this study systematically compares and analyzes four representative NR raw materials: air dried sheet (ADS), ribbed smoked sheets (RSS), constant viscidity NR (CV), and whole field latex rubber (WF). The investigation focuses on evaluating their static mechanical behavior, SIC behavior, wear resistance, and fatigue resistance. The findings indicate that protein and gel content exhibit a crucial influence on the NR properties. These constituents contribute to the formation of a high-crosslinking density region, generating a heterogeneous network structure within the rubber. This structure amplifies strains during deformation, leading to earlier and stronger strain-induced crystallization (SIC). Among the four commercial NR brands, RSS demonstrates superior overall mechanical and dynamic properties owing to its high protein and gel content. This study serves as a valuable reference for comprehending the differences in properties among various commercial NR, thereby offering guidance for the actual processing and selection of NR.

关键词： Natural rubber Processingmethod Protein Gel content Property