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Electroanalytical tools to investigate the divalent state of Eu(Ⅲ) and Nd(Ⅲ) ions in non-aqueous medium 被引量:1
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作者 Jignasu P Mehta Himanshu M Pandya Kahan I Pandya 《Journal of Rare Earths》 SCIE EI CAS CSCD 2012年第4期392-396,共5页
The divalent state of Ln(III) ions has attracted much interest because of their ability to serve isomorphously in many biological system of divalent Ca(II) ion. Therefore, present paper deals with the study of div... The divalent state of Ln(III) ions has attracted much interest because of their ability to serve isomorphously in many biological system of divalent Ca(II) ion. Therefore, present paper deals with the study of divalent state of Eu(III) and Nd(III) ions in non-aqueous medium. In present study, cyclic voltammetry and chronopotentiometry were utilized to establish the divalent state of Eu(III) and Nd(III) ions. The cyclic voltammetric technique showed two-step reduction process at cathode for both Ln(III) ions under specified experimental conditions and chronopotentiometric method also showed two different transition times (r). Looking to the shape of cyclic voltammogram we calculated het- erogeneous forward rate constant (K^fh, cm/s) and diffusion coefficient (D, cm2/s) for both ions, which suggested that sweep rate had great ef- fect on the shape of cyclic voltammogram of Eu(III) and Nd(III) ions. The result of chronopotentiometry also suggested that stable divalent states of Eu(III) and Nd(III) ions existed with chronopotentiogram with two distinct transition times. The diffusion coefficients (D, cm2/s) were calculated from Sand equation. The diffusion coefficients of both techniques were compared and the results suggested that the system at electrode surface was changing from being reversible to irreversible. 展开更多
关键词 Eu(IlI) and Nd(III) ions non-aqueous medium CYCLIC-VOLTAMMETRY chronopotentiomentry rare earths
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Tetrathiafulvalene esters with high redox potentials and improved solubilities for non-aqueous redox flow battery applications
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作者 Weikang Hu Jiaqi Xu +3 位作者 Nanjie Chen Zongcai Deng Yuekun Lai Dongyang Chen 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第5期899-908,共10页
The exploitation of high performance redox-active substances is critically important for the development of non-aqueous redoxflow batteries.Herein,three tetrathiofulvalene(TTF)derivatives with different substitution gr... The exploitation of high performance redox-active substances is critically important for the development of non-aqueous redoxflow batteries.Herein,three tetrathiofulvalene(TTF)derivatives with different substitution groups,namely TTF diethyl ester(TTFDE),TTF tetramethyl ester(TTFTM),and TTF tetraethyl ester(TTFTE),are prepared and their energy storage properties are evaluated.It has been found that the redox potential and solubility of these TTF derivatives in conventional carbonate electrolytes increases with the number of ester groups.The battery with a catholyte of 0.2 mol L^(-1) of TTFTE delivers a specific capacity of more than 10 Ah L^(-1) at the current density of 0.5 C with two discharge voltage platforms locating at as high as 3.85 and 3.60 V vs.Li/Liþ.Its capacity retention can be improved from 2.34 Ah L^(-1) to 3.60 Ah L^(-1) after 100 cycles by the use of an anion exchange membrane to block the crossover of TTF species.The excellent cycling stability of the TIF esters is supported by their well-delocalized electrons,as revealed by the density function theory calculations.Therefore,the introduction of more and larger electron-withdrawing groups is a promising strategy to simultaneously increase the redox-potential and solubility of redox-active ma-terials for non-aqueous redoxflow batteries. 展开更多
关键词 non-aqueous redox flow batteries Tetrathiofulvarene Redox potential SOLUBILITY Substituent effect
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Preparation of FeCoNi medium entropy alloy from Fe^(3+)-Co^(2+)-Ni^(2+)solution system
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作者 Zongyou Cheng Qing Zhao +3 位作者 Mengjie Tao Jijun Du Xingxi Huang Chengjun Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期92-101,共10页
In recent years,medium entropy alloys have become a research hotspot due to their excellent physical and chemical performances.By controlling reasonable elemental composition and processing parameters,the medium entro... In recent years,medium entropy alloys have become a research hotspot due to their excellent physical and chemical performances.By controlling reasonable elemental composition and processing parameters,the medium entropy alloys can exhibit similar properties to high entropy alloys and have lower costs.In this paper,a FeCoNi medium entropy alloy precursor was prepared via sol-gel and coprecipitation methods,respectively,and FeCoNi medium entropy alloys were prepared by carbothermal and hydrogen reduction.The phases and magnetic properties of FeCoNi medium entropy alloy were investigated.Results showed that FeCoNi medium entropy alloy was produced by carbothermal and hydrogen reduction at 1500℃.Some carbon was detected in the FeCoNi medium entropy alloy prepared by carbothermal reduction.The alloy prepared by hydrogen reduction was uniform and showed a relatively high purity.Moreover,the hydrogen reduction product exhibited better saturation magnetization and lower coercivity. 展开更多
关键词 medium entropy alloy SOL-GEL CO-PRECIPITATION carbothermal hydrogen reduction
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Effect of Nb-V microalloying on the hot deformation behavior of medium Mn steels
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作者 Yumeng Wang Qinyi Guo +1 位作者 Bin Hu Haiwen Luo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期360-368,共9页
The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression tests.By establishing the constitutive equations for simulati... The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression tests.By establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(Q)maps and processing maps for identifying the region of flow instability.We concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present. 展开更多
关键词 medium manganese steel niobium-vanadium microalloying flow behavior dynamic recrystallization hot workability
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As-cast Ti_(x)(AlVCr)_(100−x)light-weight medium entropy alloys with high strength and uniform compressive plasticity
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作者 Ming-jie KAI Yu-jie MA +7 位作者 Xiao-tian WANG Liang CHENG Jian-bo HU Yao-yao HU Tai-ran XU Gui-jiang LI Xiang-kang MENG Zhen-hua CAO 《中国有色金属学报》 北大核心 2025年第1期194-206,共13页
The effect of Ti content on the microstructure and mechanical properties of as-cast light-weight Ti_(x)(AlVCr)_(100−x)medium entropy alloys was studied by compressive tests,X-ray diffraction,scanning electron microsco... The effect of Ti content on the microstructure and mechanical properties of as-cast light-weight Ti_(x)(AlVCr)_(100−x)medium entropy alloys was studied by compressive tests,X-ray diffraction,scanning electron microscopy and transmission electron microscopy.The results suggest that yield strength increases and then decreases with the increment of Ti content.The Ti_(60)(AlVCr)_(40)alloy has the best combination of high strength of 1204 MPa and uniform plastic strain of 70%,possessing a high specific yield strength of 255 MPa·cm^(3)/g.The enhancement of strength is mainly attributed to the synergic effects of solid-solution and coherent nano-precipitation strengthening,while dislocation motion such as dislocation pinning,entanglement and dislocation cells significantly increases the strain-hardening capacity. 展开更多
关键词 TiAlVCr medium entropy alloy solid solution strengthening b2 precipitate strain hardening behavior
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Advances in Application of Non-aqueous Phase Enzymatic Catalysis in Food Additive Production 被引量:1
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作者 余泗莲 余琳 +4 位作者 余彬 孙文敬 刘长峰 杨梦依 崔凤杰 《Agricultural Science & Technology》 CAS 2013年第1期169-175,共7页
Non-aqueous phase enzymatic catalysis technology has been widely ap- plied in the area of food additives production. This paper reviewed the types of re- action medium of non-aqueous phase enzymatic catalysis reaction... Non-aqueous phase enzymatic catalysis technology has been widely ap- plied in the area of food additives production. This paper reviewed the types of re- action medium of non-aqueous phase enzymatic catalysis reaction, introduced the application of non-aqueous phase enzymatic catalysis technology in catalysis of L-ascorbic (isoascorbic) acid esters, short-chain acid esters, sugar esters, vitamin A esters, vi- tamin E esters, and other food additives, and finally predicted the prospects of non- aqueous phase enzymatic catalysis technology. 展开更多
关键词 non-aqueous phase Enzymatic catalysis Food additives Ester synthesis
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Non-aqueous lithium bromine battery of high energy density with carbon coated membrane 被引量:1
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作者 Xiaoli Xi Xianfeng Li +4 位作者 Chenhui Wang Qinzhi Lai Yuanhui Cheng Pengcheng Xu Huamin Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第4期639-646,共8页
Flow batteries with high energy density and long cycle life have been pursued to advance the progress of energy storage and grid application. Non-aqueous batteries with wide voltage windows represent a promising techn... Flow batteries with high energy density and long cycle life have been pursued to advance the progress of energy storage and grid application. Non-aqueous batteries with wide voltage windows represent a promising technology without the limitation of water electrolysis, but they suffer from low electrolyte concentration and unsatisfactory battery performance. Here, a non-aqueous lithium bromine rechargeable battery is proposed, which is based on Br;/Br;and Li;/Li as active redox pairs, with fast redox kinetics and good stability. The Li/Br battery combines the advantages of high output voltage(;.1 V),electrolyte concentration(3.0 mol/L), maximum power density(29.1 m W/cm;) and practical energy density(232.6 Wh/kg). Additionally, the battery displays a columbic efficiency(CE) of 90.0%, a voltage efficiency(VE) of 88.0% and an energy efficiency(EE) of 80.0% at 1.0 m A/cm;after continuously running for more than 1000 cycles, which is by far the longest cycle life reported for non-aqueous flow batteries. 展开更多
关键词 non-aqueous BATTERY LITHIUM BROMINE ENERGY-STORAGE
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Modeling Non-aqueous Phase Liquid Displacement Process 被引量:2
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作者 Yang Zhenqing Shao Changjin Zhou Guanggang Qiu Chao 《Petroleum Science》 SCIE CAS CSCD 2007年第3期40-46,共7页
A pore-network model physically based on pore level multiphase flow was used to study the water-non-aqueous phase liquid (NAPL) displacement process, especially the effects of wettability, water-NAPL interracial ten... A pore-network model physically based on pore level multiphase flow was used to study the water-non-aqueous phase liquid (NAPL) displacement process, especially the effects of wettability, water-NAPL interracial tension, the fraction of NAPL-wet pores, and initial water saturation on the displacement. The computed data show that with the wettability of the mineral surfaces changing from strongly water-wet to NAPL-wet, capillary pressure and the NAPL relative permeability gradually decrease, while water-NAPL interfacial tension has little effect on water relative permeability, but initial water saturation has a strong effect on water and NAPL relative permeabilities. The analytical results may help to understand the micro-structure displacement process of non-aqueous phase liquid and to provide the theoretical basis for controlling NAPL migration. 展开更多
关键词 non-aqueous phase liquid pore-network model capillary pressure relative permeability
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Organic Electrode Materials for Non-aqueous K-Ion Batteries 被引量:1
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作者 Mingtan Wang Wenjing Lu +1 位作者 Huamin Zhang Xianfeng Li 《Transactions of Tianjin University》 EI CAS 2021年第1期1-23,共23页
The demands for high-performance and low-cost batteries make K-ion batteries(KIBs) considered as promising supplements or alternatives for Li-ion batteries(LIBs). Nevertheless, there are only a small amount of convent... The demands for high-performance and low-cost batteries make K-ion batteries(KIBs) considered as promising supplements or alternatives for Li-ion batteries(LIBs). Nevertheless, there are only a small amount of conventional inorganic electrode materials that can be used in KIBs, due to the large radius of K^+ ions. Diff erently, organic electrode materials(OEMs) generally own sufficiently interstitial space and good structure flexibility, which can maintain superior performance in K-ion systems. Therefore, in recent years, more and more investigations have been focused on OEMs for KIBs. This review will comprehensively cover the researches on OEMs in KIBs in order to accelerate the research and development of KIBs. The reaction mechanism, electrochemical behavior, etc., of OEMs will all be summarized in detail and deeply. Emphasis is placed to overview the performance improvement strategies of OEMs and the characteristic superiority of OEMs in KIBs compared with LIBs and Na-ion batteries. 展开更多
关键词 Energy storage KIBS Organic electrode materials non-aqueous
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Design of the reactive dyes containing large planar multi-conjugated systems and their application in non-aqueous dyeing 被引量:1
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作者 Aiqin Gao Xiang Luo +3 位作者 Huanghuang Chen Aiqin Hou Hongjuan Zhang Kongliang Xie 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期264-271,共8页
The development of pollution-free dyeing technology, including anhydrous dyeing and non-aqueous dyeing technologies, has always been an important way and research hot in energy conservation and emission reduction. Des... The development of pollution-free dyeing technology, including anhydrous dyeing and non-aqueous dyeing technologies, has always been an important way and research hot in energy conservation and emission reduction. Designing new structural dye molecules is the key to water-saving dyeing processes.Herein, three reactive dyes were designed and synthesized, which contained large planar multiconjugated systems and multi-reactive groups. The designed reactive dyes are expected to have high affinity and high fixations in non-aqueous or small bath dyeing processes. The reactive dyes were applied in the decamethylcyclopentasiloxane(DMCS) reverse micelle dyeing for cotton fabric. High exhaustion rate of 99.35%, 98.10% and 98.80%, and fixation rate of 95.15%, 96.34% and 94.40% for three dyes, R1,R2 and R3, could be respectively obtained. The dyes can be fully utilized and had excellent dyeing performance, fastness and levelling properties under the revere micelle dyeing. The cotton fabric is like an oil-water separator in the dyeing process, where the dye micelles rapidly absorb and permeate into the cotton fibers. DMCS circulates around the fabric to transfer mass and energy. After dyeing, the solvent can be separated quickly and reused. The new reactive dyes containing large planar and multi-conjugated systems have potential application in green and sustainable dyeing technology with less wastewater and higher utilization. 展开更多
关键词 Reactive dyes non-aqueous dyeing High fixation rate Waste water Synthesis RECOVERY
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Systematic approaches to improving the performance of polyoxometalates in non-aqueous redox flow batteries 被引量:1
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作者 Yuan Cao Jee-Jay J.Chen Mark A.Barteau 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第11期115-124,共10页
Polyoxometalates have been explored as multi-electron active species in both aqueous and non-aqueous redox flow batteries. Although non-aqueous systems in principle offer a wider voltage window for redox flow battery ... Polyoxometalates have been explored as multi-electron active species in both aqueous and non-aqueous redox flow batteries. Although non-aqueous systems in principle offer a wider voltage window for redox flow battery operation, realization of this potential requires a judicious choice of solvent as well as polyoxometalate properties. We demonstrate here the superior performance of N,N-dimethylformamide(DMF)compared to acetonitrile as a solvent for redox flow batteries based on Li3PMo12O40. This compound displays two 1-electron transfers in acetonitrile but can access an extra quasi-reversible 2-electron redox process in DMF. A cell containing 10 mM solution of Li3PMo12O40 in DMF produced a cell voltage of 0.7 V with 2-electron transfers(State of Charge = 60%) and showed a good cyclability. As a means to boost energy density, operation of the redox flow battery at a higher concentration of 0.1 M Li3PMo12O40 produced cells with cell voltage of 0.6 V in acetonitrile and a cell voltage of 1.0 V in DMF;both showed excellent coulombic efficiencies of more than 90% over the course of 30 cycles. Energy density was also increased by employing an asymmetric cell with different polyoxometalates on each side to extend cell voltage.Li6P2W18O62 exhibited 3 quasi-reversible 2-electron transfers in the potential range between-2.05 V and-0.5 V vs. Ag/Ag+. 10 mM Li6P2W18O62/Li3PMo12O40 in DMF produced a cell with cell voltage of 1.3 V involving 4-electron transfers(State of Charge = 50%) with coulombic efficiency of nearly 100% and energy efficiency of nearly 70% throughout the test with more than 20 cycles. These promising results demonstrate proof-of-concept approaches to improving the performance of polyoxometalates in non-aqueous redox flow batteries. 展开更多
关键词 POLYOXOMETALATE Energy density Redox flow battery non-aqueous battery Cyclic voltammetry Bulk electrolysis
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Kinetic Mass Transfer Between Non-aqueous Phase Liquid and Gas During Soil Vapor Extraction 被引量:1
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作者 李鑫钢 黄国强 沈铁孟 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第5期610-613,共4页
The mass transfer between non-aqueous phase liquid(NAPL) phase and soil gas phase in soil vapor extraction(SVE) process has been investigated by one-dimensional venting experiments. During quasi-steady volatilization ... The mass transfer between non-aqueous phase liquid(NAPL) phase and soil gas phase in soil vapor extraction(SVE) process has been investigated by one-dimensional venting experiments. During quasi-steady volatilization of three single-component NAPLs in a sandy soil, constant initial lumped mass transfer coefficient (λgN,0) canbe obtained if the relative saturation (ξ) between NAPL phase and gas phase is higher than a critical value (ξc), andthe lumped mass transfer coefficient decreases with ξ when ξ<ξc. It is also shown that the lumped mass transfercoefficient can be increased by blending porous micro-particles into the sandy soil because of the increasing of theinterfacial area. 展开更多
关键词 kinetic mass transfer soil vapor extraction non-aqueous phase liquid soil remediation
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Intense up-conversion emissions of yb3+/Dy3+ co-doped A12O3 nanopowders prepared by non-aqueous sol-gel method* 被引量:2
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作者 李成仁 李淑凤 +3 位作者 董斌 孙景昌 卜晓峰 范旭楠 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期505-508,共4页
yb3+/Dy3+ co-doped A1203 nanopowders have been prepared by the non-aqueous sol-gel method and their up- conversion photoluminescence spectra are measured under excitation by a 980-nm semiconductor laser. The results... yb3+/Dy3+ co-doped A1203 nanopowders have been prepared by the non-aqueous sol-gel method and their up- conversion photoluminescence spectra are measured under excitation by a 980-nm semiconductor laser. The results show that there are comparatively abundant spectra of up-conversion emissions centered at 378, 408, 527 and 543, and 663 nm, corresponding to 4C9/2→ 6H13/2, 4C9/2→ 6Hll/2, 4115/2 → 6H13/2, and 4F9/2 →6Hll/2 transitions of Dy3+, respectively. Two-photon and three-photon processes are involved in ultraviolet, violet, green, and red up-conversion emissions. The energy transition between Yb3+ and Dy3+ is discussed. 展开更多
关键词 yb3+/Dy3+ co-doped A1203 nanopowders non-aqueous sol-gel method photo- lumi-nescence spectra up-conversion emission
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Vesicle Formation from Equimolar Cationic-anionic Surfactant Mixture in Non-aqueous Media 被引量:1
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作者 Guo Xi ZHAO Zhen Le YANG Bu Yao ZHU (Department of Chemistry. Peking University, 100871) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第6期539-542,共4页
Unilamellar vesicles from the mixtures of 1:1 sodium 10-undecenoate and trimethyl[2-(10-undecenoyloxy)ethyl]ammonium iodide in the mixed solvents of ethanol and heptane can be formed spontaneously or by sonication. Th... Unilamellar vesicles from the mixtures of 1:1 sodium 10-undecenoate and trimethyl[2-(10-undecenoyloxy)ethyl]ammonium iodide in the mixed solvents of ethanol and heptane can be formed spontaneously or by sonication. They can exist in the variation of concentrations and volume ratios of ethanol to heptane, which indicates to some extent the high capability of vesicle formation in such mixed systems. 展开更多
关键词 Vesicle Formation from Equimolar Cationic-anionic Surfactant Mixture in non-aqueous Media OOA
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Review on the plastic instability of medium -Mn steels for identifying the formation mechanisms of Lüders and Portevin -Le Chatelier bands 被引量:3
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作者 Bin Hu Han Sui +3 位作者 Qinghua Wen Zheng Wang Alexander Gramlich Haiwen Luo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1285-1297,共13页
Plastic instability,including both the discontinuous yielding and stress serrations,has been frequently observed during the tensile deformation of medium-Mn steels(MMnS)and has been intensively studied in recent years... Plastic instability,including both the discontinuous yielding and stress serrations,has been frequently observed during the tensile deformation of medium-Mn steels(MMnS)and has been intensively studied in recent years.Unfortunately,research results are controversial,and no consensus has been achieved regarding the topic.Here,we first summarize all the possible factors that affect the yielding and flow stress serrations in MMnS,including the morphology and stability of austenite,the feature of the phase interface,and the deformation parameters.Then,we propose a universal mechanism to explain the conflicting experimental results.We conclude that the discontinuous yielding can be attributed to the lack of mobile dislocation before deformation and the rapid dislocation multiplication at the beginning of plastic deformation.Meanwhile,the results show that the stress serrations are formed due to the pinning and depinning between dislocations and interstitial atoms in austenite.Strain-induced martensitic transformation,influenced by the mechanical stability of austenite grain and deformation parameters,should not be the intrinsic cause of plastic instability.However,it can intensify or weaken the discontinuous yielding and the stress serrations by affecting the mobility and density of dislocations,as well as the interaction between the interstitial atoms and dislocations in austenite grains. 展开更多
关键词 medium manganese steel discontinuous yielding stress serrations retained austenite dislocations
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Conditioned medium from human dental pulp stem cells treats spinal cord injury by inhibiting microglial pyroptosis 被引量:3
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作者 Tao Liu Ziqian Ma +8 位作者 Liang Liu Yilun Pei Qichao Wu Songjie Xu Yadong Liu Nan Ding Yun Guan Yan Zhang Xueming Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1105-1111,共7页
Human dental pulp stem cell transplantation has been shown to be an effective therapeutic strategy for spinal cord injury.However,whether the human dental pulp stem cell secretome can contribute to functional recovery... Human dental pulp stem cell transplantation has been shown to be an effective therapeutic strategy for spinal cord injury.However,whether the human dental pulp stem cell secretome can contribute to functional recovery after spinal cord injury remains unclear.In the present study,we established a rat model of spinal cord injury based on impact injury from a dropped weight and then intraperitoneally injected the rats with conditioned medium from human dental pulp stem cells.We found that the conditioned medium effectively promoted the recovery of sensory and motor functions in rats with spinal cord injury,decreased expression of the microglial pyroptosis markers NLRP3,GSDMD,caspase-1,and interleukin-1β,promoted axonal and myelin regeneration,and inhibited the formation of glial scars.In addition,in a lipopolysaccharide-induced BV2 microglia model,conditioned medium from human dental pulp stem cells protected cells from pyroptosis by inhibiting the NLRP3/caspase-1/interleukin-1βpathway.These results indicate that conditioned medium from human dental pulp stem cells can reduce microglial pyroptosis by inhibiting the NLRP3/caspase-1/interleukin-1βpathway,thereby promoting the recovery of neurological function after spinal cord injury.Therefore,conditioned medium from human dental pulp stem cells may become an alternative therapy for spinal cord injury. 展开更多
关键词 BV2 conditioned medium dental pulp stem cells GSDMD MICROGLIA NEUROINFLAMMATION NLRP3 PYROPTOSIS spinal cord injury
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In-situ Characterization of Non-aqueous Nano-dispersion Systems by Freeze-etching TEM and Comparative Study with Laser Scattering Method
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作者 欧忠文 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第3期432-436,共5页
In-situ characterization of non-aqueous nano-dispersion systems(NANDS) by freeze-etching transmission electron microscope(FETEM) was reported.To improve just-for-once successive rate of specimen preparation and ge... In-situ characterization of non-aqueous nano-dispersion systems(NANDS) by freeze-etching transmission electron microscope(FETEM) was reported.To improve just-for-once successive rate of specimen preparation and get good characterization results,an improving specimen preparation method of freezing etching was developed.Size,distribution and morphology of NANDS were directly visualized.Some information of particle dispersion feature and particle density can also be obtained.Reproductivity of the FETEM characterization is excellent.Comparing with laser scattering method,which is liable to give positive error especially for small size particle anchoring disperser,FETEM characterization can give more accurate measurement of particle size.Moreover,FETEM can give dispersion feature of nanoparticle in non-aqueous medium. 展开更多
关键词 non-aqueous nano-dispersion system dispersion state in-situ characterization FREEZE-ETCHING laser scattering method
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Analyses of non-aqueous reactive polymer insulation layer in high geothermal tunnel
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作者 Yu Chen Shiyu Wang +2 位作者 Chengchao Guo Cungang Lin Chenyang Zhao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第1期169-178,共10页
The scenario of geothermal tunnel is commonly observed around the world,and increases with the new constructions in the long and deep tunnels,for example in China.Tunnel insulation is generally divided into active and... The scenario of geothermal tunnel is commonly observed around the world,and increases with the new constructions in the long and deep tunnels,for example in China.Tunnel insulation is generally divided into active and passive insulation.In passive insulation,it is an effective way to set low thermal con-ductivity materials as the thermal insulation layer as the choice of insulation material mainly depends on the thermal conductivity.Polymer is a kind of material with good geothermal performance,but there are relatively few studies.In this context,the transient plane source(TPS)method was used to measure the thermal conductivity of the developed polymer.Then,the temperature field of the high geothermal tunnel insulated by the non-aqueous reactive polymer layer was simulated.With the parametric analysis results,the suggestions for the tunnel layers were proposed accordingly.It revealed that the thermal conductivity of polymer first increases and then decreases with temperature.There are two rising sec-tions(?40e10?C and 20e90?C),one flat section(10e20?C)and one descending section(>90?C).It is observed the thermal conductivity of polymer increases with increase of the density of insulation layer and the density,and the thermal conductivity decreases when exposed to high temperatures.The temperature of the surrounding rocks increases with increase of the thermal conductivity and the thickness of polymer.Finally,a more economical thickness(5 cm)was proposed.Based on the parametric study,a thermal insulation layer with thermal conductivity less than 0.045 W/(m K),thickness of 5 cm and a density less than 0.12 g/cm 3 is suggested for practice. 展开更多
关键词 Geothermal tunnel non-aqueous reactive polymer Thermal conductivity Heat insulation
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Preparation and characterization of alumina nanoparticles in non-aqueous solution
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作者 张少明 王涑波 胡双启 《Journal of Measurement Science and Instrumentation》 CAS 2012年第4期317-319,共3页
Nanometer Al2O3powder is prepared by sol-gel method.Trans mission electron microscope(TEM),X-ray diffrac-tion(XRD),ther mal analysis,IR and the grain-testing instructure are used to characterize the particle shape and... Nanometer Al2O3powder is prepared by sol-gel method.Trans mission electron microscope(TEM),X-ray diffrac-tion(XRD),ther mal analysis,IR and the grain-testing instructure are used to characterize the particle shape and phase,chemical bonds of hydrous cassiterite andsize distribution after being heated.XRDand TEMshowthat the powder is fibrous γ-Al2O3at800 ℃andsphericalα-Al2O3at1 200℃.The grain-testinginstructure shows that the average particle diameter of γ-Al2O3is36.2nm while that ofα-Al2O3is125.6nm.The IRshows that aluminumstearate is synthesizedin the process of sol-gel. 展开更多
关键词 stearic acid non-aqueous solution AI2 03 PREPARATION CHARACTERIZATION
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Determination of Roxithromycin Tablets by Capillary Electrophoresis Employing Non-aqueous Media with Square-wave Amperometric Detection
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作者 Na LI Tian Yao XIE Jin Yuan MO 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第5期440-441,共2页
A new method of determination for roxithromycin tablets by non-aqueous capillary electrophoresis (NACE) with square-wave amperometric detection was carried out. Several parameters affecting the NACE-AD determination ... A new method of determination for roxithromycin tablets by non-aqueous capillary electrophoresis (NACE) with square-wave amperometric detection was carried out. Several parameters affecting the NACE-AD determination were studied. The data was modified by spline wavelet least square (SWLS). The method is simple, rapid and highly reliable for routine analysis. 展开更多
关键词 non-aqueous capillary electrophoresis (NACE) amperometric detection ROXITHROMYCIN spline wavelet least square (SWLS).
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