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    题名 作者 年代 出处 被引量
1Effect of SiC whiskers on the oxidation protective properties of SiC coatings for carbon/carbon composites显示文摘以便有效地采用唯一的高温度碳 / 碳的机械性质合成底层,原文如此,涂层增强了由原文如此,络腮胡子被包装硬化方法准备。效果原文如此,单个层的涂层和双层涂层的氧化抵抗性质上的络腮胡子被调查。原文如此络腮胡子在单个层原文如此涂层在反氧化性质上有小效果,但是显然改进热吃惊性质。有内部层的增强的涂层的双层涂层与原文如此内部层的涂层比双层涂层展出更多的完美的反氧化能力。SHI Xiaohong LI Hejun FU Qiangang LI Kezhi ZHANG Xiulian 2006Rare Metals2006,25,1:33
2Reovirus,isolated from SARS patients显示文摘Beijing has been severely affected by SARS, and SARS-associated coronavirus has been confirmed as its cause. However, clinical and experimental evidence implicates the possibility of co-infection. In this report, reovirus was isolated from throat swabs of SARS patients, including the first case in Beijing and her mother. Identification with the electron microscopy revealed the characteristic features of reovirus. 24 of 38 samples from other SARS cases were found to have serologic responses to the reovirus. Primers designed for reovirus have amplified several fragments of DNA, one of which was sequenced (S2 gene fragment), which indicates it as a unique reovirus (orthoreovirus). Preliminary animal experiment showed that inoculation of the reovirus in mice caused death with atypical pneumonia. Nevertheless, the association of reovirus with SARS outbreak requires to be further investigated.DUANQing ZHUHong YANGYi LIWeihua ZHOUYusen HEJun HEKun ZHANGHaojie ZHOUTao SONGLihua GANYonghua TANHua JINBaofeng LIHuiyan ZUOTingting CHENDehui ZHANGXuemin 2003Chinese Science Bulletin2003,48,13:16
3Microstructure and Properties of Cu-Cr-Zr Alloy after Rapidly Solidified Aging and Solid Solution Aging显示文摘The structure and properties of Cu-Cr-Zr alloy were studied after rapidly solidified aging and solid solution aging.At the early stage of aging (500℃ for 15 min), the hardness and the conductivity of the alloy rapidly solidified are 143 HV and 72% IACS, respectively. Under the same aging condition, the hardness and electrical conductivity of the alloy solid solution treated can reach 86 HV and 47% lACS, respectively. The microstructure was analyzed, and the grain size after rapid solidification is much smaller than that after solid solution treatment. By rapidly solidified aging the fine precipitates distribute inside the grains and along the grain boundary, while by solid solution aging there are large Cr particles along the grain boundary.Ping LIU Juanhua SU Qiming DONG Hejun LI 2005Journal of Materials Science & Technology2005,21,4:14
4Silicon assistant carbothermal reduction for SiC powders显示文摘The silicon assistant method to increase the reaction yield of carbothermal reduction of silica at a lower temperature is reported. The effect of silicon on the carbothermal reduction process has been investigated in detail. Compared with traditional reduction, the introduction of silicon can change the reaction path and further increase the conversion of silicon carbide at a lower temperature. It is considered that the assistant reduction consists of three steps: vaporizing and melting of silicon, formation of silicon monoxide, and synthesis of silicon carbide. The morphology of the synthesized SiC powders through the silicon assistant method can be affected apparently by the experimental temperature.Kezhi Li Jian Wei Hejun Li Chuang Wang Gengsheng Jiao 2008Journal of University of Science and Technology Beijing2008,15,4:12
5Phenotypic and genetic variation between two populations of the Chinese yellow pond turtle, Mauremys mutica (Cantor, 1842)显示文摘Mauremys mutica(Cantor,1842)is an endangered species in China.Main phenotypic variations inbody color,body weight,body shape,clutch size,egg size,and hatchling size were revealed betweenthe southern and northern populations.Both populations have the phenomenon of'larger male'sexualsize dimorphism(SSD),especially in the southern population.Furthermore,genetic variations betweenthe two populations were analyzed by RAPD band patterns of 30 random individuals in each population.The average genetic distance was 0.299±0.108 among the samples of two populations.The average ge-netic distance between southern and northern populations was 0.305±0.046.Cluster analysis indicatedthat all the individuals from the southern and northern populations were clustered among themselves toform two distinct clades.A total of 20 population-specific RAPD fragments were scored from 16 primers,and could be used as RAPD markers for distinguishing the southern and the northern population.Basedon the nucleotide sequences of two RAPD markers,two pairs of SCAR primers(SC1-S and SC2-S)weredesigned,which could be used as SCAR markers for the southern population.According to the significantphenotypic and genetic variations,we suggested that the northern population and southern populationmight be considered as two separate taxa,the'northern taxon'and the'southern taxon',and the con-servation should be respectively conducted on the two taxa.朱新平 Zhou Li Chen Yongle Du Hejun Gui Jianfang 2008High Technology Letters2008,14,1:10
6Increasing the Tensile Property of Unidirectional Carbon/Carbon Composites by Grafting Carbon Nanotubes onto Carbon Fibers by Electrophoretic Deposition显示文摘Although in-situ growing carbon nanotubes(CNTs) on carbon fibers could greatly increase the matrix-dominated mechanical properties of carbon/carbon composites(C/Cs),it always decreased the tensile strength of carbon fibers.In this work,CNTs were introduced into unidirectional carbon fiber(CF) preforms by electrophoretic deposition(EPD) and they were used to reinforce C/Cs.Effects of the content of CNTs introduced by EPD on tensile property of unidirectional C/Cs were investigated.Results demonstrated that EPD could be used as a simple and efficient method to fabricate carbon nanotube reinforced C/Cs(CNT—C/Cs) with excellent tensile strength,which pays a meaningful way to maximize the global performance of CNT—C/Cs.Qiang Song Kezhi Li Hejun Li Qiangang Fu 2013Journal of Materials Science & Technology2013,29,8:9
7Advances in ultra-high temperature ceramics,composites,and coatings显示文摘Ultra-high temperature ceramics(UHTCs)are generally referred to the carbides,nitrides,and borides of the transition metals,with the Group IVB compounds(Zr&Hf)and TaC as the main focus.The UHTCs are endowed with ultra-high melting points,excellent mechanical properties,and ablation resistance at elevated temperatures.These unique combinations of properties make them promising materials for extremely environmental structural applications in rocket and hypersonic vehicles,particularly nozzles,leading edges,and engine components,etc.In addition to bulk UHTCs,UHTC coatings and fiber reinforced UHTC composites are extensively developed and applied to avoid the intrinsic brittleness and poor thermal shock resistance of bulk ceramics.Recently,high-entropy UHTCs are developed rapidly and attract a lot of attention as an emerging direction for ultra-high temperature materials.This review presents the state of the art of processing approaches,microstructure design and properties of UHTCs from bulk materials to composites and coatings,as well as the future directions.Dewei NI Yuan CHENG Jiaping ZHANG Ji-Xuan LIU Ji ZOU Bowen CHEN Haoyang WU Hejun LI Shaoming DONG Jiecai HAN Xinghong ZHANG Qiangang FU Guo-Jun ZHANG 2022Journal of Advanced Ceramics2022,11,1:9
8液态模锻力学成形理论的研究显示文摘液态模锻既是一个物理化学(凝固)过程,亦是一个力学成形(塑性变形、强制补缩)过程,两者的复合,便形成了液态模锻自身理论。本文重点放在力学成形过程方面,力图利用金属塑性加工理论,结合液态模锻本身的特点,从理论和试验的结合上,系统地推出液态模锻力学成形理论的最新研究成果。(Harbin Institute of Technology) Luo Shoujing Huo Wencan Li Hejun 1995锻压技术1995,20,5:7
9Micro/nano multiscale reinforcing strategies toward extreme high-temperature applications:Take carbon/carbon composites and their coatings as the examples显示文摘Carbon fiber reinforced carbon composites(C/Cs),are the most promising high-temperature materials and could be widely applied in aerospace and nucleation fields,owing to their superior performances.However,C/Cs are very susceptible to destructive oxidation and thus fail at elevated temperatures.Though matrix modification and coating technologies with Si-based and ultra-high temperature ceramics(UHTCs)are valid to enhance the oxidation/ablation resistance of C/Cs,it’s not sufficient to satisfy the increasing practical applications,due to the inherent brittleness of ceramics,mismatch issues between coatings and C/C substrates,and the fact that carbonaceous matrices are easily prone to high-temperature oxidation.To effectively solve the aforementioned problems,micro/nano multiscale reinforcing strategies have been developed for C/Cs and/or the coatings over the past two decades,to fabricate C/Cs with high strength and excellent high-temperature stability.This review is to systematically summarize the most recent major and important advancements in some micro/nano multiscale strategies,including nanoparticles,nanowires,carbon nanotubes/fibers,whiskers,graphene,ceramic fibers and hybrid micro/nano structures,for C/Cs and/or the coatings,to achieve high-temperature oxidation/ablation-resistant C/Cs.Finally,this review is concluded with an outlook of major unsolved problems,challenges to be met and future research advice for C/Cs with excellent comprehensive mechanical-thermal performance.It’s hoped that a better understanding of this review will be of high scientific and industrial interest,since it provides unusual and feasible new ideas to develop potential and practical C/Cs with improved high-temperature mechanical and oxidation/ablation-resistant properties.Qiangang Fu Pei Zhang Lei Zhuang Lei Zhou Jiaping Zhang Jie Wang Xianghui Hou Ralf Riedel Hejun Li 2022Journal of Materials Science & Technology2022,,1:7
10Low-cost, green synthesis of highly porous carbons derived from lotus root shell as superior performance electrode materials in supercapacitor显示文摘Facile production of high quality activated carbons from biomass materials has greatly triggered much attention presently. In this paper, a series of interconnected porous carbon materials from lotus root shells biomass are prepared via simple pyrolysis and followed by a KOH activation process. The prepared carbons exhibit high specific surface areas of up to 2961 m^2/g and large pore volume~1.47 cm3/g. In addition, the resultant porous carbons served as electrode materials in supercapacitor exhibit high specific capacitance and outstanding recycling stability and high energy density. In particular, their specific capacitance retention was almost 100% after 10500 cycles at a current density of 2 A/g. Remarkabely, the impact of the tailored specific surface areas of various carbon samples on their capacitive performances is systematically investigated.Generally, it was believed that the highly-developed porosity features(including surface areas and pore volume and pore size-distributions), together with the good conductivity of activated carbon species, play a key role in effectively improving the storage energy performances of the porous carbon electrode materials in supercapacitor.Xin Wang Mengjiao Wang Xuemei Zhang Hejun Li Xiaohui Guo 2016Journal of Energy Chemistry2016,25,1:6
11Influence of Interfacial Bonding between Metal Droplets on Tensile Properties of 7075 Aluminum Billets by Additive Manufacturing Technique显示文摘7075 aluminum billets were fabricated by micro droplet deposition manufacturing technique,and the influence of interfacial bonding between metal droplets on the tensile properties was studied.Three sets of samples were manufactured under different temperature conditions,and their mechanical properties were compared.The results show that the temperature of the metal droplets and substrate signi?cantly affect the tensile strength of the sample.Moreover,with proper temperature setting,the 7075 aluminum billets manufactured by micro metal droplet deposition could achieve very good mechanical properties with a tensile strength of 373 MPa and an elongation of 9.95%,which are very similar to those of an extruded sample.Moreover,a metallurgical bonding diagram based on numerical calculations of interfacial temperature was established to predict the interfacial bonding state.In addition,the fracture morphologies of these specimens were observed.It is indicated that there was a signi?cant transformation of failure mechanism with the improvement of metallurgical bonding,which agreed well with the numerical results.Hansong Zuo Hejun Li Lehua Qi Songyi Zhong 2016Journal of Materials Science & Technology2016,32,5:6
12Microstructure and flexural properties of carbon/carbon composite with in-situ grown carbon nanotube as secondary reinforcement显示文摘Carbon nanotubes (CNTs) were in-situ grown in carbon felts using ferric chloride as catalyst and natural gas as carbon precursor via thermal gradient chemical vapor infiltration (TGCVI). Subsequently, the carbon felts were densified to obtain CNT reinforced carbon/carbon (C/C) composites in the same furnace. Effects of CNTs on the microstructure and flexural property of C/C composites were investigated by polarized light microscopy, Raman spectroscopy, scanning electron microscopy and universal mechanical testing machine. The results of PLM observation and Raman analysis showed that CNTs have two-sided effects on the microstructure of pyrocarbon: the pyrocarbons in the region without CNTs show medium texture; while, in the region full of CNTs, the microstructure was low-textured or even isotropic though the TGCVD conditions would lead to the deposition of pure low texture pyrocarbons. Analysis based on stress-strain curves demonstrated that the flexural strength increased first and then decreased with the CNT content increasing. When the CNT content was 5.23 wt%, the flexural strength was maximum and had a nearly 35% improvement compared with pure C/C composite. Besides, after adding CNTs, the flexural modulus of the composites decreased and the ductility increased obviously, indicating CNTs can toughen C/C composites.Hai Zhang Lingjun Guo Qiang Song Qiangang Fu Hejun Li Kezhi Li 2013Progress in Natural Science:Materials International2013,23,2:6
13Effect of Temperature on the Synthesis of SiC Coating on Carbon Fibers by the Reaction of SiO with the Deposited Pyrolytic Carbon Layer显示文摘The influence of reaction temperature on the preparation of SiC coating on carbon fibers by the reaction of silicon monoxide with the deposited pyrolytic carbon (PyC) layer has been discussed.With rising reaction temperature,the thickness of SiC layer increases and the SiC grain is coarsening.The apparent activation energy for the synthesis of SiC layer is about 103.3 kJ/mol.The oxidation resistance of carbon fiber can be improved by the SiC/PyC layers significantly.The initial oxidation temperature of the SiC/PyC coated carbon fiber is about 300℃ higher than that of the uncoated carbon fiber.The oxidation of the SiC/PyC coated carbon fiber is owing to the diffusion of oxygen through the cracks generated by the mismatch of thermal expansion.Hejun Li,Haibo Ouyang,Lehua Qi,Yulei Zhang,Zhengjia Li and Jianfeng Wei C/C Composites Research Center,Key Laboratory of Ultrahigh Temperature Composites,Northwestern Polytechnical University,Xi an 710072,China 2010Journal of Materials Science & Technology2010,26,3:5
14Ablative and Mechanical Properties of C/C—ZrC Composites Prepared by Precursor Infiltration and Pyrolysis Process显示文摘C/C-ZrC composites with continuous ZrC matrix were prepared by precursor infiltration and pyrolysis process using zirconium-containing polymer.Ablation properties of the composites were investigated by oxyacetylene flame with heat flux of 2380 and 4180 kW/m^2,respectively.The results showed that C/C-ZrC composites exhibited excellent ablation resistance under the heat flux of 2380 kW/m^2 for 120 s and a tree-coral-like ZrO_2protective layer formed after ablation.However,when the heat flux increased to 4180 kW/m^2,the maximum temperature of ablated surface reached 2500 ℃ and a strong degradation of ablation resistance was observed due to the weak bonding between the formed ZrO_2 layer and the composites.The flexural strength of C/C-ZrC composites was 110.7 ± 7.5 MPa.There were a large number of carbon fiber bundles pull-out,and the composites exhibited a pseudo-plastic fracture behavior.Kezhi Li Jing Xie Hejun Li Qiangang Fu 2015Journal of Materials Science & Technology2015,31,1:5
15CMTM4 inhibits cell proliferation and migration via AKT, ERK1/2,and STAT3 pathway in colorectal cancer显示文摘CMTM4(CKLF-like MARVEL transmembrane domain containing 4),a potential tumor suppressor gene,is involved in several types of malignancies.It has been reported to be downregulated and exhibit anti-tumorigenic activities by regulating cell growth and cell cycle in clear cell renal cell carcinoma.It has also been identified as a tumor suppressor in hepatocellular carcinoma(HCC),and its negative expression is a risk factor for poor prognosis of HCC patients.In the present study,an integrated bioinformatics analysis based on The Cancer Genome Atlas(TCGA)database showed that CMTM4 was frequently reduced in colorectal cancer(CRC)and high expression of CMTM4 was associated with increased overall survival rates.Based on these findings,we adopted gain-of-function and lost-of-function strategies using SW480 and HT29 CRC cell lines which have relatively low and high endogenous CMTM4 levels,respectively.We observed impeded cell proliferation and migration upon overexpression of CMTM4 in SW480 cells,and the opposite effects were observed upon knockdown of CMTM4 in HT-29 cells.Cell signaling pathways essential for CRC progression were then examined,and the phosphorylation levels of AKT,ERK1/2,and STAT3 were found to be decreased by CMTM4 overexpression in SW480 cells and elevated by CMTM4 silencing in HT29 cells.Their inhibitors were used to validate that the three signaling pathways contributed to the inhibitory effects of CMTM4 on CRC cells.Taken together,our results suggest that CMTM4 plays a tumor suppressive role in CRC.Hui Xue Ting Li Pingzhang Wang Xiaoning Mo Hejun Zhang Shigang Ding Dalong Ma Wenping Lv Jing Zhang Wenling Han 2019Acta Biochimica et Biophysica Sinica2019,51,9:5
16Mullite Oxidation Resistant Coating for SiC-coated Carbon/Carbon Composites by Supersonic Plasma Spraying显示文摘To improve the oxidation resistance of carbon/carbon (C/C) composites, mullite coating was prepared on the surface of SiC-coated C/C composites by supersonic plasma spraying. Phases and microstructures of mullite coating were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The coating primarily consists of a single phase of mullite (3Al2O3-2SiO2). The SEM results show that mullite coating was continuous and well bonded with the SiC inner layer without penetrating crack. Mullite coating exhibited good oxidation resistance. After 98.5 h oxidation at 1773 K and 9 thermal shock cycles between 1773 K and room temperature, the weight loss of the coated C/C composites was only 2.57%.Chao Ma Hejun Li Heng Wu Qiangang Fu Can Sun Xiaohong Shi Yulei Zhang Zhengzhong Zhang Jun Tao Zhihai Han 2013Journal of Materials Science & Technology2013,29,1:4
17SiC-Si-ZrSiO_4 Multiphase Oxidation Protective Coating for Carbon/Carbon Composites显示文摘In order to improve the anti-oxidation property of carbon/carbon (C/C) composites,a novel SiC-Si-ZrSiO_4 multiphase oxidation protective coating was produced on the surface of C/SiC coated carbon/carbon compos- ites by a pack cementation technique.The phase composition and microstructure of the as-prepared coatings were characterized by XRD (X-ray diffraction),SEM (scanning electron microscopy) and EDS (energy dis- persive spectroscopy).Oxidation behavior of the multiphase coated C/C composites was also investigated. It showed that the as-prepared coating characterized by excellent oxidation resistance and thermal shock re- sistance could effectively protect C/C composites from oxidation at 1773 K for 57 h in air and endure the thermal cycle between 1773 K and room temperature for 12 times,whereas the corresponding weight loss is only 1.47%.The excellent oxidation protective ability of the SiC-Si-ZrSiO_4 coating could be attributed to the C/SiC gradient inner layer and the multiphase microstructure of the coating.Yulei ZHANG Hejun LI Qiangang FU Kezhi LI Dangshe HOU 2008Journal of Materials Science & Technology2008,24,6:4
18SiC Nanowires Toughed HfC Ablative Coating for C/C Composites显示文摘In order to improve ablation resistance of carbon/carbon(C/C) composites,SiC nanowires were prepared on C/C composites surface in prior through chemical vapor reaction before HfC coating.SiC nanowires grew randomly and had good combination with HfC coating.SiC nanowires toughed HfC coating had lower linear and mass ablation rates than original HfC coating.The surface was much flatter and exhibited smaller cracks in center region.The ablation mechanism of HfC coating has been changed by SiC nanowires.Thicker HfO2 fused layer was formed on the surface of the toughed HfC coating,which could provide efficient protection for C/C composites.Therefore,SiC nanowires toughed HfC coating behaved in better ablation resistance.Hejun Li Yongjie Wang Qiangang Fu Yanhui Chu 2015Journal of Materials Science & Technology2015,31,1:4
19Oxidation Protective C/SiC/Si-SiC Multilayer Coating for Carbon/Carbon Composites Applying at 1873 K显示文摘A C/SiC/Si-SiC multilayer coating for protecting carbon/carbon(C/C) composites against oxidation was prepared by slurry and pack cementation.X-ray diffraction(XRD) and energy dispersive spectroscopy(EDS) analysis showed that the inner coating obtained from the slurry and pack cementation was a C/SiC gradient layer acting as bonding layer,and the exterior coating formed in the second pack cementation was a Si-SiC double phase coating.Oxidation tests at 1873 K in air showed that the coating exhibited excellent oxidation protective ability and thermal shock resistance.The coating could effectively protect C/C composites from oxidation at 1873 K in air for 170 h and undergo the thermal cycling between 1873 K and room temperature for 8 cycles.The weight loss of the coated C/C composites is due to the formation of cracks and holes in the coating and the volatilization of SiO2 glass at high temperature.Yulei Zhang,Hejun Li,Xinfa Qiang and Kezhi Li C/C Composites Research Center,State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi an 710072,China 2010Journal of Materials Science & Technology2010,26,12:4
20Ablative Property of C/C–SiC–HfC Composites Prepared via Precursor Infiltration and Pyrolysis under 3,000 °C Oxyacetylene Torch显示文摘C/C–SiC–HfC composites were fabricated via precursor infiltration and pyrolysis using a mixture solution of organic hafnium-containing polymer and polycarbosilane as precursor. The microstructures and the phases of the composites were analyzed by scanning electron microscopy and X-ray diffraction. The ablation resistance of the composites was evaluated under 3,000 °C oxyacetylene torch. After ablation for 120 s, the composites exhibit good ablation properties with the linear and mass ablation rates of 9.1 9 10-4mm/s and 1.30 9 10-3g/s, which are far lower than those of the C/C–SiC composites. The excellent ablative property of the C/C–SiC–HfC composites is resulted from the formation of HfO2 molten layer on the surface of the composites, which could play a positive role in reducing heat transfer and preventing oxygen transport to the underlying carbon substrate.Min Yan Hejun Li Qiangang Fu Jing Xie Lei Liu Bo Feng 2014Acta Metallurgica Sinica(English Letters)2014,27,6:4
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