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Influence of High Temperature Treatment on the Performance of Nickel-Induced Laterally Crystallized Thin Film Transistors
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作者 秦明 樊路加 +1 位作者 VincentPoon C.Y.Yuen 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第6期571-576,共6页
Well known for their good performance,thin film transistors (TFTs) with active layers which were nickel induced laterally crystallized,are fabricated by conventional process of dual gate CMOS.The influence of pre h... Well known for their good performance,thin film transistors (TFTs) with active layers which were nickel induced laterally crystallized,are fabricated by conventional process of dual gate CMOS.The influence of pre high temperature treatment of device fabrication on the performance of TFTs is also investigated.The experiment shows that the high temperature treatment affects the performance of the devices strongly.The best performance is obtained by adopting pre treatment of 1000℃.The mobility of 314cm 2/(V·s) is obtained at NMOS TFTs with pre treatment of 1000℃,which is 10% and 22% higher than that treated at 1100℃ and without pre high temperature treatment,respectively.A maximum on/off current ratio of 3×10 8 is also obtained at 1000℃.Further investigation of uniformity verifies that the result is reliable. 展开更多
关键词 nickel induced lateral crystallization thin film transistor high temperature treatment
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Effects of High Temperature Treatment on Seed Germination of Dodonaea viscosa(L.) Jacq 被引量:1
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作者 Guangfei ZHANG Dongfang HUO +4 位作者 Boqiang HUANG Huihong ZHANG Ting YU Liyuan MENG Wenhua SU 《Agricultural Science & Technology》 CAS 2017年第1期82-86,共5页
Seeds of Dodonaea viscosa (L.) Jacq, a representative species in dry and hot valleys in Southwest China, were chosen as experimental materials. In this experiment, the D. viscosa seeds were treated at 40, 60, 80 and... Seeds of Dodonaea viscosa (L.) Jacq, a representative species in dry and hot valleys in Southwest China, were chosen as experimental materials. In this experiment, the D. viscosa seeds were treated at 40, 60, 80 and 100℃ respectively before germination to study impacts of high temperature treatment on their generation rate and to further discuss the roles of fire during the process of vegetation formation in dry and hot valley areas of China. The results show that when the temperature was higher than 40 ℃, the germination rate of D. viscosa seeds was significantly higher than that of the control group, and the heat shock effect was apparent. The germination rate was the highest when the seeds were treated at 80 ℃ for 10 min, reaching 63.00%±2.55%. There was still a significant heat shock effect on the D. viscosa seeds which were stored for one year. In comparison with the conventional method of soaking seeds in hot water, the germination rate of D. viscose seeds which were treated at high temperature before germination increased significantly. 展开更多
关键词 High temperature treatment Dodonaea viscose (L.) Jacq Germination rate Heat shock effect Vegetation restoration
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Effect of Low Temperature Treatment on Agrobacterium-mediated Transformation of Maize Seed Buds 被引量:1
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作者 Mengyu LYU Fushuang DONG +6 位作者 Junmin ZHANG He ZHAO Jianfang CHAI Shuo ZHOU Fan YANG Yongwei LIU Haibo WANG 《Agricultural Biotechnology》 CAS 2018年第3期75-76,共2页
[Objectives]This study was conducted to improve the genetic transformation rate of maize. [Methods]The seeds of maize " Zheng 58" as the experimental material were germinated and treated under freezing temperature o... [Objectives]This study was conducted to improve the genetic transformation rate of maize. [Methods]The seeds of maize " Zheng 58" as the experimental material were germinated and treated under freezing temperature of-18 ℃ for 30 and 35 min. The EGFP gene was transformed into the growth points of these seed buds by Agrobacterium tumefaciens EHA105. The transformation effect was determined by fluorescence protein detection on transformed buds. [Results]After a certain period of treatment at-18 ℃ following germination and transformation of maize bud growth points with A. tumefaciens,although the survival rate of maize buds was reduced,the percentage of transformed cells significantly increased. [Conclusions]Low temperature treatment can improve the transformation efficiency of A. tumefaciens to the growth point of maize bud. 展开更多
关键词 Maize buds Low temperature treatment AGROBACTERIUM TRANSGENIC
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Carbon spheres prepared via solvent-thermal reaction method and their microstructures after high temperature treatment
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作者 尹彩流 文国富 +3 位作者 黄启忠 王秀飞 何良明 刘宝容 《Journal of Central South University》 SCIE EI CAS 2010年第5期895-898,共4页
Carbon spheres with size of 50-300 nm were synthesized via a solvent-thermal reaction with calcium carbide and chloroform as reactants in a sealed autoclave.The morphologies and microstructures of carbon spheres befor... Carbon spheres with size of 50-300 nm were synthesized via a solvent-thermal reaction with calcium carbide and chloroform as reactants in a sealed autoclave.The morphologies and microstructures of carbon spheres before and after high temperature treatment(HTT) were characterized by X-ray diffractometry(XRD) ,scanning electronic microscopy(SEM) ,energy diffraction spectroscopy(EDS) ,and transmission electron microscopy(TEM) .The formation mechanism of carbon spheres was discussed.The results indicate that the carbon spheres convert to hollow polyhedron through HTT.Carbon spheres are composed of entangled and curve graphitic layers with short range order similar to cotton structure,and carbon polyhedron with dimension of 50-250 nm and shell thickness of 15-30 nm.The change of solid spheres to hollow polyhedron with branches gives a new evidence for formation mechanism of hollow carbon spheres. 展开更多
关键词 carbon spheres solvent-thermal method MICROSTRUCTURE high temperature treatment
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Effects of Low Temperature Treatment on Bolting of Radish(Raphanus sativus L.)
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作者 Xiaowei YUAN Keyou CAO Xingsheng LI 《Agricultural Biotechnology》 CAS 2021年第4期29-31,共3页
[Objectives]This study was conducted to screen out a vernalization method of radish that is more suitable for breeding and hybrid production.[Methods]Eight radish inbred lines with different bolting tolerance were use... [Objectives]This study was conducted to screen out a vernalization method of radish that is more suitable for breeding and hybrid production.[Methods]Eight radish inbred lines with different bolting tolerance were used as the research objects for the experiment.The following three treatments were done:(1)treating at 4℃in the dark with heat preservation for 1,2,3,4,and 5 weeks,respectively~([1]),(2)treating at 4℃in the dark with heat preservation for 3 weeks after 24 h incubation in light at 20℃,and(3)treating under light at a low temperature of 6.5℃for three weeks after cultivating under light at 20℃to 4 true leaves.The effects of low temperature treatment on the bolting and flowering time of different varieties of radish treated at different developmental stages were analyzed.[Results]When comparing these three methods,the low-temperature treatment of wet seeds had a better effect on early bolting of radish and is simpler and more feasible.The effect of treating four-leaf seedlings at 6.5℃was the worst;most radish inbred lines could shorten bolting time when treated at 4℃for one week;and within a certain range,the longer the 4℃treatment time,the better the vernalization effect.Different radish inbred lines had different performances to low temperature treatment.[Conclusions]This study provides a scientific basis for the theoretical research on vernalization of radish. 展开更多
关键词 RADISH Low temperature treatment BOLTING Development period
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Mechanical properties of Mg-6Gd-1Y-0.5Zr alloy processed by low temperature thermo-mechanical treatment 被引量:1
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作者 李德江 曾小勤 +3 位作者 谢艳才 吴玉娟 丁文江 陈彬 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第10期2351-2356,共6页
An as-solution treated Mg-6Gd-1Y-0.4Zr alloy was processed by low temperature thermo-mechanical treatments (LT-TMT), including cold tension with various strains followed by aging at 200 °C to peak hardness. The... An as-solution treated Mg-6Gd-1Y-0.4Zr alloy was processed by low temperature thermo-mechanical treatments (LT-TMT), including cold tension with various strains followed by aging at 200 °C to peak hardness. The results show that the precipitation kinetics of the alloy experienced LT-TMT is greatly accelerated and the aging time to peak hardness is greatly decreased with increasing tensile strain. The tensile yield strength, ultimate tensile strength and elongation at room temperature of the alloy after cold tension with strain of 10% and peak aging at 200 °C are 251 MPa, 296 MPa and 8%, respectively, which are superior to the commercial heat-resistant WE54 alloy, although the latter has a higher rare earth element content. 展开更多
关键词 Mg-Gd-Y-Zr alloy low temperature thermo-mechanical treatment precipitation hardening mechanical properties
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Effects of heat treatment temperature on oxidation behavior of glass-like carbon derived from acetone-furfural resin
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作者 夏伦刚 张红波 熊翔 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第2期330-334,共5页
Glass-like carbons (GCs) were prepared by carbonization of acetone-furfural resin in nitrogen atmosphere at 850℃, followed by heat treatment over a range of 1 200-2 500℃in inert atmosphere. The effect of heat trea... Glass-like carbons (GCs) were prepared by carbonization of acetone-furfural resin in nitrogen atmosphere at 850℃, followed by heat treatment over a range of 1 200-2 500℃in inert atmosphere. The effect of heat treatment temperature (HTT) on the oxidation behavior was investigated by dynamic and isothermal thermogravimetric analyses. The structure of GC was examined by X-ray diffractometry (XRD) and the morphologies of GC before and after oxidation were examined by scanning electron microscopy (SEM). It is shown that the GC samples present peculiar oxidation behavior. The anti-oxidation behavior increases with increasing the HTT to 1 600 ℃, whereas decreases gradually thereafter. GC sample heat treated at 1 600℃ obtains relatively optimal anti-oxidation properties under this condition. During the oxidation, this material produces grid network matrix surface and numerous nodular residues on the surface, resulting in excellent resistance to the attack of oxygen atoms. 展开更多
关键词 glass-like carbon acetone-furfural KINETICS heat treatment temperature microstructure
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Effect of low temperature thermo-mechanical treatment on microstructures and mechanical properties of TC4 alloy 被引量:8
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作者 孙利平 林高用 +1 位作者 刘健 曾菊花 《Journal of Central South University》 SCIE EI CAS 2010年第3期443-448,共6页
The effects of low temperature thermo-mechanical treatment (LTTMT) on microstructures and mechanical properties of Ti-6Al-4V (TC4) alloy were studied by optical microscopy (OM), tensile test, scanning electron m... The effects of low temperature thermo-mechanical treatment (LTTMT) on microstructures and mechanical properties of Ti-6Al-4V (TC4) alloy were studied by optical microscopy (OM), tensile test, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The experimental results confirm that the strength of TC4 alloy can be improved obviously by LTTMT processing, which combines strain strengthening with aging strengthening. The effect of LTTMT on the alloy depends on the microstructure of the refined and dispersed a+fl phase on the basis of high dislocation density by pre-deformation below recrystallization temperature. The tensile strength decreases with the increase of pre-deformation reduction. The optimal processing parameters of LTTMT for TC4 alloy are as follows: solution treatment at 900 ℃ for 15 min, pre-deformation in the range of 600-700 ℃ with a reduction of 35%, finally aging at 540 ℃ for 4 h followed by air-cooling. 展开更多
关键词 Ti-6Al-4V (TC4) alloy low temperature thermo-mechanical treatment MICROSTRUCTURE mechanical properties strain strengthening
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Effect of Heat Treatment Temperature on Properties of Chinese Calcined Flint Clay Based Plastic Refractories 被引量:24
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作者 ZHANG Wei DAI Wenyong YU Xinfeng LI Liang 《China's Refractories》 CAS 2009年第2期27-29,共3页
Effects of different heat treatment temperatures on properties of Chinese calcined flint clay based plastic refractories were investigated using Chinese calcined flint clay as starting material, aluminum sulfate and f... Effects of different heat treatment temperatures on properties of Chinese calcined flint clay based plastic refractories were investigated using Chinese calcined flint clay as starting material, aluminum sulfate and fireclay as binding system. The results showed that with temperature rising, Chinese calcined flint clay based plastic refractories shrinked firstly and then expanded. The modulus of rupture (MOR) and the cold crushing strength (CCS) inereased firstly and then decreased from 110 ℃ to 600 ℃ , then increased obviously. Thermal expansion coefficient increased from 110 ℃ to 760 ℃, decreased from 760 ℃ to 1 300 ℃ , and increased from 1 300 ℃ to1500 ℃. 展开更多
关键词 Chinese calcined flint clay based plastic refractories Fireclay Heat treatment temperature Thermal expansion coefficient
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Fretting Wear Behavior of Medium Carbon Steel Modified by Low Temperature Gas Multi-component Thermo-chemical Treatment 被引量:3
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作者 LUO Jun ZHENG Jianfeng PENG Jinfang HE Liping ZHU Minhao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第3期288-296,共9页
The introduction of surface engineering is expected to be an effective strategy against fretting damage. A large number of studies show that the low gas multi-component (such as carbon, nitrogen, sulphur and oxygen, ... The introduction of surface engineering is expected to be an effective strategy against fretting damage. A large number of studies show that the low gas multi-component (such as carbon, nitrogen, sulphur and oxygen, etc) thermo-chemical treatment(LTGMTT) can overcome the brittleness of nitriding process, and upgrade the surface hardness and improve the wear resistance and fatigue properties of the work-pieces significantly. However, there are few reports on the anti-fretting properties of the LTGMTT modified layer up to now, which limits the applications of fretting. So this paper discusses the fretting wear behavior of modified layer on the surface of LZ50 (0.48%C) steel prepared by low temperature gas multi-component thermo-chemical treatment (LTGMTT) technology. The fretting wear tests of the modified layer flat specimens and its substrate (LZ50 steel) against 52100 steel balls with diameter of 40 mm are carried out under normal load of 150 N and displacement amplitudes varied from 2 μm to 40 μm. Characterization of the modified layer and dynamic analyses in combination with microscopic examinations were performed through the means of scanning electron microscope(SEM), optical microscope(OM), X-ray diffraction(XRD) and surface profilometer. The experimental results showed that the modified layer with a total thickness of 60 μm was consisted of three parts, i.e., loose layer, compound layer and diffusion layer. Compared with the substrate, the range of the mixed fretting regime(MFR) of the LTGMTT modified layer diminished, and the slip regime(SR) of the modified layer shifted to the direction of smaller displacement amplitude. The coefficient of friction(COF) of the modified layer was lower than that of the substrate in the initial stage. For the modified layer, the damage in partial slip regime(PSR) was very slight. The fretting wear mechanism of the modified layer both in MFR and SR was abrasive wear and delamination. The modified layer presented better wear resistance than the substrate in PSR and MFR; however, in SR, the wear resistance of the modified layer decreased with the increase of the displacement amplitudes. The experimental results can provide some experimental bases for promoting industrial application of LTGMTT modified layer in anti-fretting wear. 展开更多
关键词 fretting wear fretting regimes low temperature gas multi-component thermo-chemical treatment(LTGMTT) modified layer medium carbon steel
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Effect of Treatment Temperature on Iron Nitride Foils Irradiated with Nitrogen Plasma 被引量:1
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作者 K.Niizuma and Y. Utsushiforwa (College of Industrial Technology, Nihon University, Narashino, Chiba 275-8575, Japan) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第2期143-144,共2页
We investigated the effect of treatment temperature on the magnetic property of iron nitride foils irradiated with nitrogen plasma. The iron nitride foils irradiated with nitrogen plasma were composed of ε-Fe2/3N, γ... We investigated the effect of treatment temperature on the magnetic property of iron nitride foils irradiated with nitrogen plasma. The iron nitride foils irradiated with nitrogen plasma were composed of ε-Fe2/3N, γ'-Fe4N and γ nitrogen austenite in α-Fe of the matrix. The saturation magnetization of the iron nitride foils decreased with increasing the surface temperature. The coercive force of the iron nitride foils increased with increasing the surface temperature. 展开更多
关键词 Effect of treatment temperature on Iron Nitride Foils Irradiated with Nitrogen Plasma
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Effect of heat treatment temperature of the glaze lager on the structure and the formaldehyde removal performance of an interior wall tile
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作者 Ruqin Gao Yingrui Huang +4 位作者 Enhui Wang Xinmei Hou Lu Pan Guoting Li Bingtao Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第11期2079-2085,共7页
With the improvement of people’s living standards,a large number of petroleum products,daily necessities and decorations that can produce volatile organic compounds are used in decoration,which seriously affects the ... With the improvement of people’s living standards,a large number of petroleum products,daily necessities and decorations that can produce volatile organic compounds are used in decoration,which seriously affects the indoor air quality.Interior decoration materials have become a research hotspot in recent years.The purpose of this paper is to develop a kind of interior wall material with good indoor formaldehyde removal effect,easily using,and low cost.In this paper,combining different heat treatment temperatures of the glaze layer,tourmaline/diatomite-based interior wall tiles were prepared by ultrafine grinding,solid sintering,and low temperature calcination.The glaze layer under different heat treatment temperatures was characterized by thermogravimetric-differential thermal analysis,X-ray diffraction,and scanning electron microscope.The influences of heat treatment temperature on the microscopic morphology and structure of the glaze layer were analyzed.Taking formaldehyde as the target degradation product,the effects of tourmaline/diatomite-based interior wall tiles on the removal of formaldehyde under different heat treatment temperatures of the glaze layer were investigated.The results showed that with the increase in heat treatment temperature,the original pores of diatomite decreased,the specific surface area decreased,and the structure of tourmaline changed.At 850℃,the surface structure of the material was slightly damaged,the strength was increased,and the removal effect of formaldehyde was better.In a 1 m^(3) environmental chamber,the formaldehyde removal rate reached 73.6%in 300 min.When the temperature was increased to 950℃ and above,diatomite and the structure of tourmaline were destroyed,and the ability of the material to adsorb and degrade formaldehyde decreased. 展开更多
关键词 DIATOMITE tourmaline/diatomite-based interior wall tiles glaze layer heat treatment temperature FORMALDEHYDE adsorption and degradation
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Influence of Heat Treatment Temperature on Microstructure and Bonding of TiO2 Film Coated on Diamond Particles Surface
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作者 刘小磐 KONG Weibing +4 位作者 XIAO Haiyan TANG Hao WAN Long HU Weida 王伟 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第5期1008-1012,共5页
TiO_2 films were coated on the surface of diamond particles using a sol-gel method. The effects of heat treatment temperature on the morphology, phase composition and chemical bond of diamond particles coated with TiO... TiO_2 films were coated on the surface of diamond particles using a sol-gel method. The effects of heat treatment temperature on the morphology, phase composition and chemical bond of diamond particles coated with TiO2 films were investigated through SEM, TEM, X-ray diffraction analysis, Raman spectroscopy, FTIR, and XPS. The results showed that when being heat-treated at 600 ℃, the amorphous TiO_2 film transfered to the anatase film which bonded well with diamond substrate. Meanwhile, the Ti-O-C bond formed between TiO2 film and diamond substrate. When being heat-treated at 800 ℃, TiO2 film was still anatase, and partial diamond began to graphitize. The graphitizated carbon could also form the Ti-O-C bond with TiO_2 film, although TiO_2 film would tend to crack in this case. 展开更多
关键词 diamond TiO2 film heat treatment temperature chemical bond
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Polyphenol content and antioxidant activity in mulberry powder treated at high temperature
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作者 Jiajun Yin Junan Zheng +3 位作者 Xin Li Jiaqing Cao Xinyao Guan Xiangrong Zhang 《Journal of Polyphenols》 2023年第2期81-87,共7页
The aim of this study was to investigate changes of polyphenols content and the antioxidant activity of mulberry fruit powder after heating at high temperature.The mulberry fruit powder was heated by baking method at ... The aim of this study was to investigate changes of polyphenols content and the antioxidant activity of mulberry fruit powder after heating at high temperature.The mulberry fruit powder was heated by baking method at different temperature and time.The DPPH scavenging ability,the OH^(•-) scavenging ability and the O_(2)^(•-) scavenging ability were used to evaluate the changes in the antioxidant activity of the mulberry fruit powder after the heat treatment.The results showed that 74.87%of the polyphenols in the mulberry powder were lost after heating at 150℃for 5 min,and almost all the polyphenols were lost with the increase of the heating time and temperature.The antioxidant experiment showed that the DPPH scavenging rate,OH^(•-) scavenging rate and O_(2)^(•-) scavenging rate of mulberry fruit powder were 68.90%,39.15%and 14.09%,respectively after treatment at 150℃ for 5 min.Mulberry fruit powder still has some potential to be added to baked goods as a functional ingredient. 展开更多
关键词 fruit powder POLYPHENOL MULBERRY high temperature treatment antioxidant activity
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INFLUENCE OF HEAT TREATMENT ON OXIDATION PROPERTIES OF C/C COMPOSITES FABRICATED BY HIGH PRESSURE IMPREGNATION CARBONIZATION 被引量:2
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作者 Q.Chen H.J.Li +2 位作者 A.J.Li H.M.Han K.Z.Li 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2004年第4期426-430,共5页
Felt base carbon/carbon composites fabricated by super-high pressure impregnation carbonization process (SPIC) were heat treated at high temperature 2773K. The oxidation properties of felt base carbon/carbon composite... Felt base carbon/carbon composites fabricated by super-high pressure impregnation carbonization process (SPIC) were heat treated at high temperature 2773K. The oxidation properties of felt base carbon/carbon composites were investigated at different temperatures (773-1173K), and the microstructures of carbon/carbon composites were studied by SEM and X-ray diffraction. The experimental results showed that the inter-laminar distance of (002) plane (d002) deceased while the microcrystalline stack height (Lc) increased. The oxidation rate of felt base carbon/carbon composites was invari-able at certain temperatures. The oxidation mechanism of carbon/carbon composites changed remarkably at the oxidation temperature 973K. At the initial oxidation stage of carbon/carbon composites, carbon matrix was oxidized much more rapidly than carbon felt. 展开更多
关键词 carbon/carbon composites high pressure impregnation carbonization high temperature heat treatment OXIDATION mi-crostructure
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Low-temperature Rapid Synthesis of Ultrafine Hafnium Carbide Ceramic Powders 被引量:1
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作者 吴洁 王为民 LIU Chun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第4期843-848,共6页
Nano hafnium carbide(HfC) powders were synthesized by sol-gel combining hightemperature rapid heat treatment process using citric acid and hafnium tetrachloride as the raw materials. The effects of ball milling trea... Nano hafnium carbide(HfC) powders were synthesized by sol-gel combining hightemperature rapid heat treatment process using citric acid and hafnium tetrachloride as the raw materials. The effects of ball milling treatment on the phase and morphology of pyrolysis products(HfO_2-C) and final HfC product were investigated and the influences of heat treatment temperature and holding time on the structure and properties of the synthesized hafnium carbide powders were also studied. The experimental results showed that the HfO_2-C powders with good uniformity and small particle size were prepared by controlling the milling time. Pure HfC powders with an average particle size of 500 nm were obtained at 1 700 ℃ with a holding time of 3 min, and the oxygen content was about 0.69 wt%, lower than that of the hafnium carbide powders prepared by SPS(0.97%). 展开更多
关键词 hafnium carbides SOL-GEL ball milling high temperature heat treatment
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Room temperature NO2-sensing properties of hexagonal tungsten oxide nanorods 被引量:1
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作者 Yaqiao Wu Ming Hu Yuming Tian 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第2期114-120,共7页
Hexagonal WO_3 nanorods were synthesized through a facile hydrothermal method. The nanorods properties were investigated by scanning electron microscope(SEM), transmission electron microscope(TEM), energy dispersi... Hexagonal WO_3 nanorods were synthesized through a facile hydrothermal method. The nanorods properties were investigated by scanning electron microscope(SEM), transmission electron microscope(TEM), energy dispersive spectroscopy(EDS), and x-ray diffraction(XRD). The NO_2-sensing performances in terms of sensor response, response/recovery times and repeatability at room temperature were optimized by varying the heat treatment temperature of WO_3 nanorods. The optimized NO_2sensor(400-℃-annealed WO_3 nanorods) showed an ultra-high sensor response of 3.2 and short response time of 1 s to 5-ppm NO_2. In addition, the 400-℃-annealed sample exhibited more stable repeatability.Furthermore, dynamic responses measurements of annealed samples showed that all the annealed WO_3 nanorods sensors presented p-type behaviors. We suppose the p-type behavior of the WO_3 nanorods sensor to be that an inversion layer is formed in the space charge layer when the sensor is exposed to NO_2 at room temperature.Therefore, the 400-℃-annealed WO_3 nanorods sensor is one of the most energy conservation candidates to detect NO_2 at room temperature. 展开更多
关键词 WO_3 nanorods thermal treatment NO_2 gas sensor room temperature
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Spent graphite regeneration:Exploring diverse repairing manners with impurities-catalyzing effect towards high performance and low energy consumption
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作者 Yu Dong Zihao Zeng +7 位作者 Zhengqiao Yuan Bing Wang Hai Lei Wenqing Zhao Wuyun Ai Lingchao Kong Yue Yang Peng Ge 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期656-669,共14页
Spent battery recycling has received considerable attention because of its economic and environmental potential.A large amount of retired graphite has been produced as the main electrode material,accompanied by a deta... Spent battery recycling has received considerable attention because of its economic and environmental potential.A large amount of retired graphite has been produced as the main electrode material,accompanied by a detailed exploration of the repair mechanism.However,they still suffer from unclear repair mechanisms and physicochemical evolution.In this study,spent graphite was repaired employing three methodologies:pickling-sintering,pyrogenic-recovery,and high-temperature sintering.Owing to the catalytic effect of the metal-based impurities and temperature control,the as-obtained samples displayed an ordered transformation,including the interlayer distance,crystalline degree,and grain size.As anodes of lithium ions batteries,the capacity of repaired samples reached up to 310 mA h g^(-1)above after 300loops at 1.0 C,similar to that of commercial graphite.Meanwhile,benefitting from the effective assembly of carbon atoms in internal structure of graphite at>1400℃,their initial coulombic efficiency were>87%.Even at 2.0 C,the capacity of samples remained approximately 244 mA h g^(-1)after 500 cycles.Detailed electrochemical and kinetic analyses revealed that a low temperature enhanced the isotropy,thereby enhancing the rate properties.Further,economic and environmental analyses revealed that the revenue obtained through suitable pyrogenic-recovering manners was approximately the largest value(5500$t^(-1)).Thus,this study is expected to clarify the in-depth effect of different repair methods on the traits of graphite,while offering all-round evaluations of repaired graphite. 展开更多
关键词 Spent graphite regeneration REPAIR temperature treatment
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Enhanced photocatalytic NO removal and toxic NO2 production inhibition over ZIF‐8‐derived ZnO nanoparticles with controllable amount of oxygen vacancies 被引量:5
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作者 Pengfei Zhu Xiaohe Yin +3 位作者 Xinhua Gao Guohui Dong Jingkun Xu Chuanyi Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第1期175-183,共9页
The controlled introduction of oxygen vacancies(OVs)in photocatalysts has been demonstrated to be an efficient approach for improving the separation of photogenerated charge carriers,and thus,for enhancing the photoca... The controlled introduction of oxygen vacancies(OVs)in photocatalysts has been demonstrated to be an efficient approach for improving the separation of photogenerated charge carriers,and thus,for enhancing the photocatalytic performance of photocatalysts.In this study,a two‐step calcination method where ZIF‐8 was used as the precursor was explored for the synthesis of ZIF‐8‐derived ZnO nanoparticles with gradient distribution of OVs.Electron paramagnetic resonance measurements indicated that the concentration of OVs in the samples depended on the temperature treatment process.Ultraviolet–visible spectra supported that the two‐step calcined samples presented excellent light‐harvesting ability in the ultraviolet‐to‐visible light range.Moreover,it was determined that the two‐step calcined samples presented superior photocatalytic performance for the removal of NO,and inhibited the generation of NO2.These properties could be attributed to the contribution of the OVs present in the two‐step calcined samples to their photocatalytic performance.The electrons confined by the OVs could be transferred to O2 to generate superoxide radicals,which could oxidize NO to the final product,nitrate.In particular,the NO removal efficiency of Z 350‐400(which was a sample first calcined at 350℃ for 2 h,then at 400℃ for 1 h)was 1.5 and 4.6 times higher than that of Z 400(which was one‐step directly calcined at 400℃)and commercial ZnO,respectively.These findings suggested that OV‐containing metal oxides that derived from metal‐organic framework materials hold great promise as highly efficient photocatalysts for the removal of NO. 展开更多
关键词 Photocatalytic NO removal ZIF‐8 Zinc oxide Oxygen vacancies temperature treatment
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Synthesis of Iron-containing Carbon Microparticles from Deoiled Asphalt and Ferrocene 被引量:3
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作者 YANG Yong-zhen ZHANG Chun-yi +2 位作者 JI Wei-yun LIU Xu-guang XU Bing-she 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2006年第B12期228-231,共4页
The deoiled asphalt as the carbon source and the ferrocene as the metal source and the catalyst precursor were chosen to synthesize iron-containing carbon microparticles through co-carbonization at the temperature of ... The deoiled asphalt as the carbon source and the ferrocene as the metal source and the catalyst precursor were chosen to synthesize iron-containing carbon microparticles through co-carbonization at the temperature of about 450℃ for 3 h. The resulting products were treated at 2 000 ℃ for 2 h. All samples were examined by high resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD). The results show that the iron particles in the heat-treated material are completely coated by carbon. In addition to the fully filled carbon microparticles as well as hollow carbon ones, also form carbon fibers with hollow centers. The formation mechanism of the as-prepared products was discussed briefly. 展开更多
关键词 aeronautic materials iron-containing carbon microparticles deoiled asphalt co-carbonizition high temperature heat treatment
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