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Hydration mechanism and microstructure characteristics of modified magnesium slag alkali-activated coal-fired slag based cementitious materials
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作者 SUN Wei-ji LIU Lang +4 位作者 ZHAO Yuan-yuan FANG Zhi-yu LYU Yong-zhe XIE Geng SHAO Cheng-cheng 《Journal of Central South University》 2025年第6期2148-2169,共22页
As the second most important solid waste produced by coal-fired power plants,the improper management of coal-fired slag has the potential to result in environmental pollution.It is therefore imperative that high-value... As the second most important solid waste produced by coal-fired power plants,the improper management of coal-fired slag has the potential to result in environmental pollution.It is therefore imperative that high-value utilization pathways for coal-fired slag should be developed.In this study,modified magnesium slag(MMS),produced by a magnesium smelter,was selected as the alkali activator.The activated silica-aluminum solid wastes,namely coal-fired slag(CFS)and mineral powder(MP),were employed as pozzolanic materials in the preparation of alkali-activated cementitious materials.The alkali-activated cementitious materials prepared with 50 wt%MMS,40 wt%CFS and 10 wt%MP exhibited favorable mechanical properties,with a compressive strength of 32.804 MPa in the paste sample cured for 28 d.Then,the activated silica-aluminum solid waste consisting of CFS-MP generated a significant amount of C-S(A)-H gels,AFt,and other products,which were observed to occupy the pore structure of the specimen.In addition,the secondary hydration reaction of CFS-MP occurs in high alkalinity environments,resulting in the formation of a mutually stimulated and promoted reaction system between CFS-MP and MMS,this will subsequently accelerate the hydrolysis reaction of MMS.It is important to emphasize that the amount of MMS in alkali-activated cementitious materials must be strictly regulated to avert the potential issue of incomplete depolymerization-repolymerization of active silica-aluminum solid waste containing CFS-MP.This in turn could have a deleterious impact on the late strength of the cementitious materials.The aim of this work is to improve the joint disposal of MMS,CFS and MP and thereby provide a scientific basis for the development of environmentally friendly and low-carbon modified magnesium slag alkali-activated coal-fired slag based cementitious materials for mine backfilling. 展开更多
关键词 coal-fired slag ALKALI-ACTIVATED hydration characteristics pore structure composite cementitious material
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The effect of Ti and Zr content on the structure,mechanics and energy-release characteristics of Ti—Zr—Ta alloys 被引量:1
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作者 Jia-yu Meng Jing-zhi He +4 位作者 Bin Zhang Jin Chen Shun Li Dun Niu Yu Tang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期343-350,共8页
Energetic structural materials(ESMs)are a new type of structural materials with bearing and damage characteristics.In this work the microstructure,mechanical properties and energy release characteristics of multi-elem... Energetic structural materials(ESMs)are a new type of structural materials with bearing and damage characteristics.In this work the microstructure,mechanical properties and energy release characteristics of multi-element Ti-Zr-Ta alloys with good casting performance were studied.The microstructure of the Ti_(x)ZrTa alloys gradually change from BCC+HCP to single BCC structure with the increase of Ti.While the Ti_(2)Zr_(y)Ta alloys was still uniform and single BCC structure with the increase of Zr.The evolution of microstructure and composition then greatly affect the mechanical properties and energy-release characteristics of Ti-Zr-Ta alloys.The synergistic effect of dual phase structure increases the fracture strain of Ti_(x)ZrTa(x=0.2,0.5)with the Ti content decreases,while the fracture strain of Ti_(x)ZrTa(x=2.0,3.0,4.0)gradually increase with the Ti content increases caused by the annihilation of the obstacles for dislocation movement.And as Zr content increases,the fracture strain of Ti_(2)Zr_(y)Ta alloys decrease,then the oxidation reaction rate and fragmentation degree gradually increase.The higher oxidation rate and the lager exposed oxidation area jointly leads the higher releasing energy efficiency of Ti_(x)ZrTa alloys with low Ti content and Ti_(2)Zr_(y)Ta alloys with high Zr content. 展开更多
关键词 Energetic structural materials Ti-Zr-Ta Multi-element alloy Energy release characteristics
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Geological characteristics and the origin of ore-forming materials of(Laozhaiwan gold deposit, Yunnan Province
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作者 ZHAO DeKun CHEN CuiHua +3 位作者 ZHANG Yan GU XueXiang TU ZongLin DAI HongZhang 《矿床地质》 CAS CSCD 北大核心 2014年第S1期853-854,共2页
"Golden triangle"area bordered on Yunnan-Guizhou-Guangxi was one of the most important Carlin-type gold deposits concentration areas.Deep understanding of Carlin-type gold deposits in Guizhou and Guangxi Pro... "Golden triangle"area bordered on Yunnan-Guizhou-Guangxi was one of the most important Carlin-type gold deposits concentration areas.Deep understanding of Carlin-type gold deposits in Guizhou and Guangxi Province had reached through several decades studies,but geological environment was very complex in the southeastern Yunnan,and Carlin-type gold deposits produced in the southeastern Yunnan were different from that of America,few studies were taken there.Based on a large number of field work,studies on the geological characteristics combining with geochemistry characteristics were taken,and analysis the genesis of Laozhaiwan gold deposit.The types of alteration in Laozhaiwan gold deposit were mainly silicification and pyritization,and Gold grade was high when silicification and pyritization were both occurred.It could be caculated that fluid density(g/cm3)varied from 0.7 to 4.9,salinity varied from 0.76%to 0.95%and ore-forming pressure(Pa)varied from 1.81×105 to 49.96×105 according to fluid inclusion test results,showed that Laozhaiwan gold deposit was hypabyssal hydrothermal deposit in low temperature and low salinity.According to composition of fluid inclusion analysis,combining with H-O isotope,made theδD-δ18O figure,showed that the fluid of the deposit rooted in formation water and mixed with meteoric waters later. 展开更多
关键词 Geological characteristics and the origin of ore-forming materials of Laozhaiwan gold deposit Yunnan Province
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Effects of Adhesive Characteristic on the Test Results of Damping Material's DMP
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作者 胡卫强 王敏庆 《Defence Technology(防务技术)》 SCIE EI CAS 2009年第4期281-286,共6页
In the measurement of damping material's dynamic mechanical performance(DMP) using flexural resonating cantilever beam method,the specimen's adhesive characteristic influences the test precision and accuracy. ... In the measurement of damping material's dynamic mechanical performance(DMP) using flexural resonating cantilever beam method,the specimen's adhesive characteristic influences the test precision and accuracy. Taking its effect into account,the improved measurement equations based on the resonance method are presented. The simulated results show that,for the sake of weakening the adhesive's influence on the measured results,the adhesive should be spreaded as thin as possible when specimen is prepared,the adhesive's density and loss factor should be selected as small as possible also,and its Young's modulus should be selected according to the damping material being measured;the same adhesion condition effects differently on the test results of different damping materials,i.e. the error due to the adhesive is more inconspicuous if the damping layer has bigger thickness,modulus,loss factor and a certain density according to the damping material being measured. These conclusions provide theoretical basis for selecting adhesive,improving adhesion technology,and designing specimen. 展开更多
关键词 oscillation and wave damping material flexural resonating cantilever beam method specimen in free damping form adhesive characteristic
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Energy release characteristics of PTFE/Al/TiH_(2) reactive jet with different TiH_2 content 被引量:2
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作者 Chunlan Jiang Jingbo Zhang +2 位作者 Rong Hu Liang Mao Ming Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第9期168-176,共9页
Titanium hydride(TiH_(2)), a promising high-energy additive, is doped into PTFE/Al to optimize the energy output structure of the reactive jet and strive for better aftereffect damage ability to the target. Six types ... Titanium hydride(TiH_(2)), a promising high-energy additive, is doped into PTFE/Al to optimize the energy output structure of the reactive jet and strive for better aftereffect damage ability to the target. Six types of PTFE/Al/TiH_(2) reactive liners with different TiH_(2) content are prepared by the molding and sintering method. The energy release characteristics of PTFE/Al/TiH_(2) reactive jet are tested by the transient explosion energy test, and are characterized from pressure and temperature. The reaction delay time,pressure history, and temperature history of the energy release process are obtained, then the actual value of released energy and reaction efficiency of the reactive jet are calculated. The results show that the peak pressure and temperature of the PTFE/Al/TiH_(2) jet initially increase and then decrease with increasing TiH_(2) content. When the TiH_(2) content is 10%, the actual value of released energy and reaction efficiency increased by 24% and 6.4%, respectively, compared to the PTFE/Al jet. The reaction duration of the reactive material is significantly prolonged as the TiH_(2) content increased from 0% to 30%. Finally,combined with the energy release behaviors of PAT material and the dynamic deformation process of liner, the enhancement mechanism of TiH_(2) on energy release of the reactive jet is expounded. 展开更多
关键词 PTFE/Al/TiH_(2) Reactive materials Shaped charge Impact energy release characteristics
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Study on energy release characteristics of reactive material casings under explosive loading 被引量:8
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作者 Ning Du Wei Xiong +3 位作者 Tao Wang Xian-feng Zhang Hai-hua Chen Meng-ting Tan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第5期1791-1803,共13页
Reactive Materials(RMs),a new material with structural and energy release characteristics under shockinduced chemical reactions,are promising in extensive applications in national defense and military fields.They can ... Reactive Materials(RMs),a new material with structural and energy release characteristics under shockinduced chemical reactions,are promising in extensive applications in national defense and military fields.They can increase the lethality of warheads due to their dual functionality.This paper focuses on the energy release characteristics of RM casings prepared by alloy melting and casting process under explosive loading.Explosion experiments of RM and conventional 2A12 aluminum alloy casings were conducted in free field to capture the explosive fireballs,temperature distribution,peak overpressure of the air shock wave and the fracture morphology of fragments of reactive material(RM)warhead casings by using high-speed camera,infrared thermal imager temperature and peak overpressure testing and scanning electron microscope.Results showed that an increase of both the fireball temperature and air shock wave were observed in all RM casings compared to conventional 2A12 aluminum ally casings.The RM casings can improve the peak overpressure of the air shock wave under explosion loading,though the results are different with different charge ratios.According to the energy release characteristics of the RM,increasing the thickness of RM casings will increase the peak overpressure of the near-field air shock wave,while reducing the thickness will increase the peak overpressure of the far-field air shock wave. 展开更多
关键词 Reactive materials Explosive loading Shock-induced chemical reaction Energy release characteristics FRAGMENTATION
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Call for Papers from Food Science of Animal Products
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《肉类研究》 北大核心 2025年第7期I0018-I0018,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research fi ndings in the fi eld of animal-origin foods,involving food mat... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research fi ndings in the fi eld of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product fl avor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identifi cation;cell-cultured meat,regulations and standards. 展开更多
关键词 productsmilkeggsanimal offals edible insectsthe animal origin foods nutritional components bioactive substances food materials MEAT quality processing characteristics
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Call for Papers from Food Science of Animal Products
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《食品科学》 北大核心 2025年第9期I0031-I0031,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the fi eld of animal-origin foods,involving food mate... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the fi eld of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product flavor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identifi cation;cell-cultured meat,regulations and standards. 展开更多
关键词 productsmilkeggsanimal offals edible insectsthe animal origin foods nutritional components bioactive substances food materials MEAT quality processing characteristics
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Call for Papers from Food Science of Animal Products
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《肉类研究》 北大核心 2025年第9期I0018-I0018,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research fi ndings in the fi eld of animal-origin foods,involving food mat... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research fi ndings in the fi eld of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product fl avor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identifi cation;cell-cultured meat,regulations and standards. 展开更多
关键词 productsmilkeggsanimal offals edible insectsthe animal origin foods nutritional components bioactive substances food materials MEAT quality processing characteristics
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Call for Papers from Food Science of Animal Products
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《肉类研究》 北大核心 2025年第8期I0018-I0018,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research fi ndings in the field of animal-origin foods,involving food mate... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research fi ndings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product flavor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identifi cation;cell-cultured meat,regulations and standards. 展开更多
关键词 productsmilkeggsanimal offals edible insectsthe animal origin foods nutritional components bioactive substances food materials MEAT quality processing characteristics
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Call for Papers from Food Science of Animal Products
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《食品科学》 北大核心 2025年第20期I0021-I0021,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product flavor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identification;cell-cultured meat,regulations and standards. 展开更多
关键词 edible insectsthe animal origin foods food raw materialsthe nutritional components bioactive substances food materials food science animal products issn e issn quality processing characteristics
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Call for Papers from Food Science of Animal Products
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《食品科学》 北大核心 2025年第12期I0022-I0022,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product flavor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identifi cation;cell-cultured meat,regulations and standards. 展开更多
关键词 edible insectsthe animal origin foods food raw materialsthe nutritional components bioactive substances food materials food science animal products issn e issn quality processing characteristics
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Call for Papers from Food Science of Animal Products
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《肉类研究》 北大核心 2025年第10期I0018-I0018,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product flavor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identification;cell-cultured meat,regulations and standards. 展开更多
关键词 edible insectsthe animal origin foods food raw materialsthe nutritional components bioactive substances food materials food science animal products issn e issn quality processing characteristics
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The Processing Mineralogy for Lead and Zinc Oxide Ore in Sichuan 被引量:1
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作者 YANG Mei XIAO Wending +2 位作者 YANG Xiang LIANG Dongyun WU Yan 《矿物学报》 CAS CSCD 北大核心 2013年第S1期125-125,共1页
Using variety of modern testing methods, the processing mineralogical characteristics for a lead and zinc oxide ore in Sichuan were studied systematically. The chemical analysis result shows that the lead and zinc oxi... Using variety of modern testing methods, the processing mineralogical characteristics for a lead and zinc oxide ore in Sichuan were studied systematically. The chemical analysis result shows that the lead and zinc oxide content exceeding the minimum industrial grade and iron ore, total iron content reaches a minimum industrial grade and associated with gold and silver; The mineralogical analysis result shows that lead and zinc mineral composition and configuration are very complexity. The zinc minerals and zinciferous minerals are sphalerite, hemimorphite, Smithsonite, Hydrozincite, zinc chlorite, limonite, zinc dolomite and zincocalcite; lead minerals and plumbiferous minerals are mainly galena, cerussite, anglesite, limonite and Coronadite; The minerals disseminated grain size are very fine and mineral dissemination characteristics are very complex ; expected theoretical recoveries for lead and zinc were 72% and 67% respectively. The results of this study provide basic data and theoretical basis for ore dressing. 展开更多
关键词 lead-zinc oxide ORE PROCESSING MINERALOGY material composition DISSEMINATED characteristics OCCURRENCE states
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Mechanical behavior of entangled metallic wire materials-polyurethane interpenetrating composites
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作者 Xiao-yuan Zheng Zhi-ying Ren +2 位作者 Hong-bai Bai Zhang-bin Wu You-song Guo 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第2期120-136,共17页
Composite materials exhibit the impressive mechanical properties of high damping and stiffness,which cannot be attained by employing conventional single materials.Along these lines,a novel material architecture is pre... Composite materials exhibit the impressive mechanical properties of high damping and stiffness,which cannot be attained by employing conventional single materials.Along these lines,a novel material architecture is presented in this work in order to fabricate composites with enhanced mechanical characteristics.More specifically,entangled metallic wire materials were used as the active matrix,whereas polyurethane was employed as the reinforcement elements.As a result,an entangled metallic wire material-polyurethane composite with high damping and stiffness was prepared by enforcing the vacuum infiltration method.On top of that,the mechanical properties(loss factor,energy consumption,and average stiffness)of the proposed composite materials were characterized by performing dynamic tests,and its fatigue characteristics were verified by the micro-interface bonding,as well as the macro-damage factor.The impact of the density,preloading spacing,loading amplitude,and exciting frequency on the mechanical properties of the composites were also thoroughly analyzed.The extracted results indicate that the mechanical properties of the composites were significantly enhanced than those of the pure materials due to the introduction of interface friction.Moreover,the average stiffness of the composites was about 10 times the respective value of the entangled metallic wire material.Interestingly,a rise in the loading period leads to some failure between the composite interfaces,which reduces the stiffness property but enhances the damping dissipation properties.Finally,a comprehensive dynamic mechanical model of the composites was established,while it was experimentally verified.The proposed composites possess higher damping features,i.e.,stiffness characteristics,and maintain better fatigue characteristics,which can broaden the application range of the composites.In addition,we provide a theoretical and experimental framework for the research and applications in the field of metal matrix composites. 展开更多
关键词 Entangled metallic wire material Composites materials Damping property STIFFNESS Fatigue characteristics
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Quasi-static and low-velocity impact mechanical behaviors of entangled porous metallic wire material under different temperatures
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作者 Yi-wan Wu Hu Cheng +3 位作者 Shang-zhou Li Yu Tang Hong-bai Bai Chun-hong Lu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第1期143-152,共10页
To improve the defense capability of military equipment under extreme conditions,impact-resistant and high-energy-consuming materials have to be developed.The damping characteristic of entangled porous metallic wire m... To improve the defense capability of military equipment under extreme conditions,impact-resistant and high-energy-consuming materials have to be developed.The damping characteristic of entangled porous metallic wire materials(EPMWM)for vibration isolation was previously investigated.In this paper,a study focusing on the impact-resistance of EPMWM with the consideration of ambient temperature is presented.The quasi-static and low-velocity impact mechanical behavior of EPMWM under different temperatures(25℃-300℃)are systematically studied.The results of the static compression test show that the damping energy dissipation of EPMWM increases with temperature while the nonlinear damping characteristics are gradually enhanced.During the impact experiments,the impact energy loss rate of EPMWM was between 65%and 85%,while the temperatures increased from 25℃to 300℃.Moreover,under the same drop impact conditions,the overall deformation of EPMWM decreases in the temperature range of 100℃-200℃.On the other hand,the impact stiffness,energy dissipation,and impact loss factor of EPMWM significantly increase with temperature.This can be attributed to an increase in temperature,which changes the thermal expansion coefficient and contact state of the internal wire helixes.Consequently,the energy dissipation mode(dry friction,air damping,and plastic deformation)of EPMWM is also altered.Therefore,the EPMWM may act as a potential candidate material for superior energy absorption applications. 展开更多
关键词 Entangled porous metallic wire material Low-velocity impact High temperature Energy dissipation characteristics Mechanical behavior
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Measurement of niobium reaction rate for material surveillance tests in fast reactors
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作者 Chikara Ito Shigetaka Maeda +2 位作者 Toshihiko Inoue Hideki Tomita Tetsuo Iguchi 《辐射防护》 CAS CSCD 北大核心 2020年第6期491-495,共5页
A highly accurate and precise technique for measurement of the 93 Nb(n,n’)93m Nb reaction rate was established for the material surveillance tests,etc.in fast reactors.The self-absorption effect on the measurement of... A highly accurate and precise technique for measurement of the 93 Nb(n,n’)93m Nb reaction rate was established for the material surveillance tests,etc.in fast reactors.The self-absorption effect on the measurement of the characteristic X-rays emitted by 93m Nb was decreased by the dissolution and evaporation to dryness of niobium dosimeter.A highly precise count of the number of 93 Nb atoms was obtained by measuring the niobium solution concentration using inductively coupled plasma mass spectrometry.X-rays of 93m Nb were measured accurately by means of comparing the X-ray intensity of irradiated niobium solution with that of the solution in which stable 93 Nb was added.The difference between both intensities indicates the effect of 182 Ta,which is generated from an impurity tantalum,and the intensity of X-rays from 93m Nb was evaluated.Measurement error of the 93 Nb(n,n’)93m Nb reaction rate was reduced to be less than 4%,which was equivalent to the other reaction rate errors of dosimeters used for Joyo dosimetry.In addition,an advanced technique using Resonance Ionization Mass Spectrometry was proposed for the precise measurement of 93m Nb yield,and 93m Nb will be resonance-ionized selectively by discriminating the hyperfine splitting of the atomic energy levels between 93 Nb and 93m Nb at high resolution. 展开更多
关键词 Isord-10 NIOBIUM reaction rate material surveillance test fast reactor characteristic x-rays experimental fast reactor joyo resonance ionization mass spectrometry hyperfine structure
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Structure Characterization and Performance Estimate for Thermal Solidified RDX Explosive by μCT
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作者 ZHANG Wei-bin HUANG Hui TIAN Yong ZONG He-hou DAI Bin GUAN Li-feng 《含能材料》 EI CAS CSCD 北大核心 2009年第4期499-500,共2页
关键词 建筑材料 含能材料 估计 RDX
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二硫化锡基钠离子电池负极材料研究进展 被引量:3
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作者 李倩 李常林 +4 位作者 王硕然 黄娜 王文培 马红周 翁雅青 《有色金属(中英文)》 北大核心 2025年第4期525-535,共11页
随着化石能源的消耗和人们对清洁可再生能源需求的不断增加,开发新型储能材料刻不容缓。钠离子电池因钠资源丰富,在大规模储能方面成为继锂离子电池之后最具前景的二次电池。电池的负极材料对电池的电化学性能有着重要的影响,二硫化锡... 随着化石能源的消耗和人们对清洁可再生能源需求的不断增加,开发新型储能材料刻不容缓。钠离子电池因钠资源丰富,在大规模储能方面成为继锂离子电池之后最具前景的二次电池。电池的负极材料对电池的电化学性能有着重要的影响,二硫化锡作为钠离子电池的负极材料具有高理论比容量、易于调控的形貌和优异的循环稳定性等特点,引发研究人员的广泛关注。对二硫化锡的结构以及作为钠离子电池负极材料的钠化机理进行了总结,概括了提高其电化学性能的一些方法,最后对二硫化锡负极材料在钠离子电池中面临的挑战和发展前景进行了总结和展望。 展开更多
关键词 钠离子电池 负极材料 二硫化锡 钠化机理 电化学性能
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英语教材“学材化”特征及其教学转化 被引量:1
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作者 郭宝仙 《课程.教材.教法》 北大核心 2025年第2期48-54,共7页
学习能力是当今世界共同追求的核心素养目标,也是我国英语课程要培养的学生核心素养。可以培养自学能力、用于教学的教材,已经成为学生学习使用的主要教材,即“学材”。以核心素养为导向的教材为学习而设计,基于新课标的英语教材具有较... 学习能力是当今世界共同追求的核心素养目标,也是我国英语课程要培养的学生核心素养。可以培养自学能力、用于教学的教材,已经成为学生学习使用的主要教材,即“学材”。以核心素养为导向的教材为学习而设计,基于新课标的英语教材具有较强的“学材化”特征,具体表现在可以激发学生的学习愿望,引导和支持学习过程,以及提供自主选择和开放的资源,满足不同的学习需求。“学材化”特征只有通过教学转化,才能助力培养学生的学习能力。这种转化不是简单的转码过程,而是教师通过与多元主体互动,将审定的教材转化为教师设计的教材、教学中运作的教材、再到学生体验的教材,具体的转化路径包括分析与规划、选择与设计、建构与创造。为了完成英语教材“学材化”特征的教学转化,教师要成为教材和学生需求的研究者,并不断提升自身专业素养。 展开更多
关键词 英语教材 “学材化”特征 学习能力
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