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EFFECT OF ELECTRIC FIELD ON THE AUSTENIzATION OF A LOW CARBON STEEL

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Acta Metallurgica Sinica(English Letters) 2004年第5期17卷 689-693页

作者： X.T.liu j.z.Cui TheKeyLaboratoryofElectromagneticProcessingofMaterials MinistryofEducationNortheasternUniversityShenyang110004China

With an electric field during austenitizing, the martensite transformation of the low carbon steel was promoted, and more martensite were obtained. The electric field promotes the homogeneity of carbon, and reduces the free energy of austenite. The critical neuclus r* and the critical driving force G* responsible for the nucleation of proeutectoid ferrite were increased. As a result of which the diffusion controlled proeuctoid ferrite transformation was retarded and the hardenability was improved.

关键词： austenization electric field proeutectoid ferrite hardenability

Behavior of High Performance PVA Fiber Reinforced Cement Composites in Triaxial Compression

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武汉理工大学学报 2010年第17期32卷 179-185页

作者： LI Y LIANG X W liu z j Xi'an University of Architecture and Technology Xi'an 710055China Henan Polytechnic University Jiaozuo 454003China

Based on an extensive experimental program,the paper studies the behavior of HPFRCC under triaxial compression. The experimental parameters are lateral confining pressure and PVA fiber content by volume. The test results indicate that ultimate strength and peak strain are significantly improved with the increases of confining pressure. The confining effect introduced by the fibers becomes minor in triaxial compression tests,where there is relatively high external confining pressure. The axial stress-strain curves with different confining pressure and different PVA fiber content by volume are obtained. Lateral confining pressure constraints the lateral expansion of HPFRCC,so there is a big plastic deformation with its ultimate strength improved. At lower confining pressure,PVA fiber content by volume has some effect on the decreased section of stress-strain curve. According to test results,the paper establishes formula of confining pressure with ultimate strength and axial peak strain respectively.

关键词： PVA high Performance fiber reinforced cement composites ultimate strength deformation property

Effects of Polymer Coating on the Properties of Surface Layer Concrete

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Effects of Polymer Coating on the Properties of Surface Laye...

Monte Carlo simulation of mirror magnetic field effects in a helium direct current gas discharge

2011中国材料研讨会

作者： L.Shi,j.z.liu,j.P.liu

Polymer coating is progressively being used in fields of concrete curing and concrete surface *** there is rare study been performed to investigate the effects of polymer coating on the properties of surface layer *** effects of polymer coating on shrinkage,mechanical property,carbonation,capillary absorption and chloride ion diffusion of surface layer concrete were *** results show that polymer coating can obviously reduce shrinkage of surface layer mortar.A thicker polymer coating gets a greater shrinkage reducing ratio at early *** coating can improve the early age strength of surface layer mortar compared with the specimens cured under standard ***,the carbonation resistance of surface layer concrete,as well as the infiltration resistance of surface layer mortar can be improved by polymer *** results also demonstrate that the capillary absorption ratio of mortar coated with polymer can be reduced by 87% and 78% respectively when compared with dry and standard curing *** the same way,polymer coating has an improvement effect on chloride ion diffusion resistance of surface layer concrete.

关键词： polymer coating shrinkage carbonation capillary absorption chloride ion diffusion

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Monte Carlo simulation of mirror magnetic field effects in a...

NUMERICAL SIMULATION OF STRESS-STRAIN DISTRIBUTIONS FOR WELD METAL SOLIDIFICATION CRACKING IN STAINLESS STEEL

作者： Y H liu, z L liu, K L Yao, H X liu and j z Wang Department of Physics, Huazhong University of Science and Technology and the National Laboratory of Laser Technology. Wuhan 430074, People’s Republic of China

Using the Monte Carlo method, we study the behaviour of electrons as they move under the influence of a mirror magnetic field and a uniform electric field in positive column of a helium dc gas discharge. The symmetrical axis of the mirror magnetic fields is in a direction parallel to the uniform electric field. Some types of collisions (elastic, excitation and ionization collision) ate considered. Graphs showing the electron density and the energy distributions, the angular and the energy distributions at the end of the positive column, and the percentage of electrons that reach the wall and the end of the positive column are presented. The results indicate that the mirror magnetic field can control the electron transport behaviour in the positive column. In the presence of the mirror magnetic field the electrons are restricted in the middle pan of the positive column and the electron energy is reduced;the electron scattering angles are extended by the mirror magnetic fields. These results are in good agreement with experimental results.

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Acta Metallurgica Sinica(English Letters) 2000年第1期13卷 133-138页

作者： Y. H. Wei R. P. liu and z. j. Dong( 1) National Key Laboratory of Advanced Welding Production Technology, HIT, Harbin 150001, China 2) Harbin Research institute of Welding,Harbin 150080, China)

This paper analyzed the characteristics of welding solidification crack of stainless steels,and clearly re- vealed the the of the deformation in the molten - the pool and the solidification shrinkage on the stress - strain fields in the trail of molten - weld ***, rheologic properties of the alloys in solid - liquid zone were also obtained by measuring the hading and unloading deform curves of the *** a result, a numerical model for simulation of stress - strain distributions of welding solidifi- cation crack was developed. On the basis of the model,the thesis simulated the driving force of solidifi- cation crack of stainless steels, that is, stress - strain fields in the trail of molten-weld pool with fi- nite element method.

关键词： welding solidification crack welding solidification crack driving force,finite element method stress - strain field,numerical simulation

橄榄石和橄榄岩蛇纹石化过程中气体形成的对比研究

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中国科学：地球科学 2016年第12期46卷 97-106页

作者：黄瑞芳孙卫东丁兴刘金钟彭少邦中国科学院矿物学和成矿学重点实验室中国科学院广州地球化学研究所广州510640 中国科学院边缘海地质重点实验室中国科学院南海海洋研究所广州510301 同位素地球化学国家重点实验室中国科学院广州地球化学研究所广州510640 有机地球化学国家重点实验室中国科学院广州地球化学研究所广州510640 中山市环境保护科学研究院中山528403

对比311℃,3 kbar时橄榄石和橄榄岩蛇纹石化后氢气和烷烃的产量,探讨初始物粒径大小对气体形成的影响.结果表明,橄榄石蚀变产生的氢气和甲烷远低于橄榄岩,而其乙烷和丙烷产量相当.初始粒径为<30?m的橄榄石,27天后氢气和甲烷的浓度分别为... 详细信息

对比311℃,3 kbar时橄榄石和橄榄岩蛇纹石化后氢气和烷烃的产量,探讨初始物粒径大小对气体形成的影响.结果表明,橄榄石蚀变产生的氢气和甲烷远低于橄榄岩,而其乙烷和丙烷产量相当.初始粒径为<30?m的橄榄石,27天后氢气和甲烷的浓度分别为79.6 mmol/kg和460?mol/kg.相应地,同样粒径的橄榄岩经历相同的反应时间后,氢气和烷烃的浓度分别为119 mmol/kg和1300?mol/kg,远高于橄榄石蛇纹石化产生的氢气和烷烃.这表明橄榄石和橄榄岩的蛇纹石化过程是不同的,可能是由于尖晶石和辉石的影响.此外,初始物粒径大小影响氢气和烷烃的产量,粒径大时气体的产量低,这表明费托合成可能受反应动力学的影响.因此,初始物类型及其粒径大小制约蛇纹石化过程中氢气和烷烃的形成.和本文烷烃相比,海底热液区的甲烷含量更高,高含量的烷烃可能需要催化剂的参与或者经历很长时间的蛇纹石化形成.

关键词：蛇纹石化氢气烷烃橄榄石橄榄岩

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Maximizing biomass utilization: An integrated strategy for coproducing multiple chemicals

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journal of Energy Chemistry 2025年第1期100卷 180-191页

作者： Byeongchan Ahn Sua jo jonggeol Na j.jay liu Young-ju Kim Wangyun Won Department of Chemical and Biological Engineering Korea University Department of Chemical Engineering (Integrated process) Kyung Hee University Department of Chemical Engineering and Materials Science Ewha Womans University Department of Chemical Engineering Pukyong National University Resources Engineering Plant Research Department Korea Institute of Geoscience and Mineral Resources

Lignocellulosic biomass is one of the viable solutions to alleviate the global warming. However, the limited utilization of biomass majorly focused on cellulose and hemicellulose restricts the economic and environmental feasibilities. To cope with this issue, we proposed an integrated process of co-producing 1,6-hexanediol（1,6-HDO） with tetrahydrofuran and adipic acid from biomass, referred to as Strategy A. To compare the impacts of lignin upgrading and feedstock, Strategy B, which co-produces tetrahydrofuran alone, and Strategy C, which is the traditional route to produce 1,6-HDO from fossil fuels, were used. Heat networks are also designed to reduce operating costs and indirect carbon emissions due to energy consumption, saving 87% and 83% of the heat and cooling requirements, respectively, in Strategy A. The market competitiveness of Strategy A was evaluated by determining the minimum selling price through techno-economic analysis, and sustainability was thoroughly investigated by quantifying the environmental impacts through both midpoint and endpoint life-cycle assessments（LCAs）.Strategy A was found to be the most favorable both economically（USRDSCHARDOLLAR3,402/ton） and environmentally（-26.9 kg CO2eq.）. This indicates that lignin valorization is not only economically but also environmentally preferred. Finally, changes in economic and environmental feasibilities depending on economic, process, and environmental parameters were investigated using sensitivity and uncertainty analyses. The results of these analyses provide valuable insight into bio-based chemical production.

关键词： Biorefinery Carbon mitigation Climate change Global warming Lignin utilization Bioeconomy

Rational modulation of fluorophosphate cathode by anionic groups to reduce the polarization behavior for fast-charging sodium-ion batteries

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journal of Energy Chemistry 2025年第1期100卷 509-521页

作者： Xinyuan Wang Fan zhang Xingyu zhou Qian Wang Changyu liu Yangyang liu Hui Wang Xiaojie liu Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry & Materials Science Northwest University

Na3V2（PO4）2O2F （VP） is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific *** functional theory （DFT） and finite element simulations show that incorporating SO42-into VP decreases its band gap,lowers the migration energy barrier,and ensures a uniform Na+concentration gradient and stress distribution during charge and discharge ***,the average Na+diffusion coefficient of Na3V2（PO4）1.95（SO4）0.05O2F（VPS-1） is roughly double that of VP,leading to enhanced rate capability (80 C,75.5 mAh g-1) and cycling stability (111.0 mAh g-1capacity after 1000 cycles at 10 C current density) for ***-1 exhibits outstanding fast-charging capabilities,achieving an 80%state of charge in just 8.1 *** assembled VPS-1//SbSn/NPC full cell demonstrated stable cycling over 200 cycles at a high 5 C current,maintaining an average coulombic efficiency of 95.35%.

关键词： Anionic group modulation Polarization behavior Fast-charging Sodium-ion battery Fluorophosphate Cathode

Role of the Greenland Sea ice anomaly in the late-spring drought over Northwest China

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 1-5页

作者： Yang liu Huopo Chen Nansen-zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of SciencesBeijingChina Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University for Information Science and TechnologyNanjingChina

Drought across Northwest China in late spring has exerted a vital effect on the local climate and agricultural production,and has been alleviated during the past *** study explored the influence of the preceding Arctic sea ice on the May drought in Northwest China caused by the precipitation *** analysis indicated that when the Greenland Sea ice concentration is abnormally high during February to April,the dry conditions in Northwest China tend to be *** increase of sea ice in the Greenland Sea can excite a meridional circulation,which causes sea surface temperature(SST)anomalies in the North Atlantic via the sea-air interaction,manifested as significant warm SST anomalies over the south of Greenland and the subtropical North Atlantic,but negative SST anomalies over the west of the *** abnormal SST pattern maintains to May and triggers a zonal wave train from the North Atlantic through Scandinavia and Central Asia to Northwest China,leading to abnormal cyclones in Northwest ***,Northwest China experiences a more humid climate than usual.

关键词： Arctic sea ice Greenland Sea North Atlantic SST Drought Northwest China