维普中文期刊产品整合服务
9篇 您的检索式:作者名="CHENG Zhaojun"
    题名 作者 年代 出处 被引量
1Effect of Multi-Pass Equal Channel Angular Pressing on the Microstructure and Mechanical Properties of a Heterogeneous Mg_(88)Y_8Zn_4 Alloy显示文摘The microstructure evolutions and mechanical properties of a heterogeneous Mg88Y8Zn4(in at.%) alloy during multi-pass equal channel angular pressing(ECAP) were systematically investigated in this work.The results show that four phases,i.e.α-Mg,18 R long period stacking ordered(LPSO) phase,Mg24Y5 and Y-rich phase,are present in cast alloy.During ECAP,dynamic recrystallization(DRX) occurs and the diameter of DRXedα-Mg grains decreases to 0.8 μm.Moreover,precipitation of lamellar 14 H LPSO structure is developed withinα-Mg phase.Both the refinement of α-Mg grains and precipitation of 14 H LPSO contribute to the increase in micro-hardness from 98 HV to 135 HV for α-Mg.In addition,a simplified model describing the evolution of 18 R LPSO phase is established,which illustrates that 18 R undergoes a four-step morphological evolution with increasing strains during ECAP,i.e.original lath → bent lath → cracked lath → smaller particles.Compression test results indicate that the alloy has been markedly strengthened after multi-pass ECAP,and the main reason for the significantly enhanced mechanical properties could be ascribed to the DRXed α-Mg grains,newly precipitated 14 H lamellas,18 R kinking and refined 18 R particles.Huan Liu Zhaojun Cheng Kai Yan Jingli Yan Jing Bai Jinghua Jiang Aibin Ma 2016Journal of Materials Science & Technology2016,32,12:4
2Hierarchical Micropore/Nanorod Apatite Hybrids In-Situ Grown from 3-D Printed Macroporous Ti6Al4V Implants with Improved Bioactivity and Osseointegration显示文摘The advent of three-dimensional(3-D) printed technique provides great possibility in the fabrication of customized porous titanium(Ti) implant. However, the bioinert property of the printed Ti poses an outstanding problem. Hybrid micro-arc oxidation and hydrothermal(MAO–HT) treatment on porous metals is able to produce multi-scaled hierarchical orthopedic implant, showing great potential for surface modification of 3-D printed implant. In this study, cylindrical porous Ti6Al4V(Ti64) scaffolds with pore size of 640 μm, porosity of 73% were 3-D printed by electron beam melting process, and their surfaces were left untreated or treated by a combined MAO–HT procedure. In vitro bioactivity was tested by immersion in simulated body fluid for different time points. Then, 12 scaffolds in each group were implanted into the femoral condyles of New Zealand rabbit for 8 weeks. Osseointegration was evaluated by qualitative and quantitative histological analysis, and the bone ingrowth features were probed by sequential fluorescent labeling at 3 and 6 weeks post-surgery. Following the MAO–HT treatment, the porous Ti64 scaffold was endowed with multi-scaled micro/nano-topographies and high amounts of Ca P on its surface.The treated scaffold exhibited drastically enhanced apatite forming ability compared with the untreated one. In vivo test revealed significantly that a higher amount of bone ingrowth and bone implant contact at the treated scaffold. The 2 types of scaffolds had different patterns of bone ingrowth: the treated scaffold exhibited a pattern of contact osteogenesis, by which bone formed directly on the treated implant surface, whereas bone formed distal to the implant surface of the untreated scaffold. MAO–HT treatment can significantly enhance the in vitro apatite-inducing ability and in vivo osseointegration capacity of 3-D porous Ti64 scaffold and may provide as a viable approach for the fabrication of bioactive 3-D printed porous implant for orthopedic applications.Peng Xiu Zhaojun Jia Jia Lv Chuan Yin Hong Cai Chunli Song Huijie Leng Yufeng Zheng Zhongjun Liu Yan Cheng 2017Journal of Materials Science & Technology2017,33,2:2
3Regulatory considerations for animal studies of biomaterial products显示文摘Animal studies play a vital role in validating the concept,feasibility,safety,performance and efficacy of biomaterials products during their bench-to-clinic translation.This article aims to share regulatory considerations for animal studies of biomaterial products.After briefly emphasizing the importance of animal studies,issues of animal studies during biomaterial products’translation are discussed.Animal studies with unclear purposes,flawed design and poor reporting quality could significantly reduce the translation efficiency and create regulatory challenges.Regulatory perspectives on the purpose,principle,quality and regulatory science of animal studies are also presented.Animal studies should have clear purposes,follow principles of 3R+DQ(replacement,reduction,refinement,design and quality)and execute under an efficiently operating quality management system.With the advancement of regulatory science,National Medical Products Administration of China has been developing a series of standards and guidance documents on animal studies of medical devices.Case studies of making decisions on whether to conduct animal studies are provided in the end with drug-eluting stents as examples.In summary,animal studies of biomaterial products should pay close attention to the rationale,design and quality in order to achieve their purposes.Maobo Cheng Wenbo Liu Jiazhen Zhang Song Zhang Zhaojun Guo Lu Liu Jiaxin Tian Xiangmei Zhang Jin Cheng Yinghui Liu Gang Deng Guobiao Gao Lei Sun 2022Bioactive Materials2022,7,5:1
4Customizable Ligand Exchange for Tailored Surface Property of Noble Metal Nanocrystals显示文摘It is highly desirable,while still challenging,to obtain noble metal nanocrystals with custom capping ligands,because their colloidal synthesis relies on specific capping ligands for the shape control while conventional ligand exchange processes suffer from“the strong replaces the weak”limitation,which greatly hinders their applications.Herein,we report a general and effective ligand exchange approach that can replace the native capping ligands of noble metal nanocrystals with virtually any type of ligands,producing flexibly tailored surface properties.The key is to use diethylamine with conveniently switchable binding affinity to the metal surface as an intermediate ligand.As a strong ligand,it in its original form can effectively remove the native ligands;while protonated,it loses its binding affinity and facilitates the adsorption of new ligands,especially weak ones,onto the metal surface.By this means,the irreversible order in the conventional ligand exchange processes could be overcome.The efficacy of the strategy is demonstrated by mutual exchange of the capping ligands among cetyltrimethylammonium,citrate,polyvinylpyrrolidone,and oleylamine.This novel strategy significantly expands our ability to manipulate the surface property of noble metal nanocrystals and extends their applicability to a wide range of fields,particularly biomedical applications.Qikui Fan Hao Yang Juan Ge Shumeng Zhang Zhaojun Liu Bo Lei Tao Cheng Youyong Li Yadong Yin Chuanbo Gao 2020Research2020,,1:1
5Uniqueness of Lekima compared to tropical cyclones landed in the east coast of China during 1979–2019显示文摘Tropical cyclone (TC) causes huge damage to lives and properties due to strong winds,storm surge,heavy rainfall and flooding(Peduzzi et al.,2012;Zhang et al.,2009).Climate model simulations suggested that the frequency of TCs might increase during the 21st century,especially over the western North Pacific (Emanuel,2013).Climate changes tend to double the economic damages caused by natural disaster,i.e.,strong TCs.East Asia hit by TCs may suffer great damages in the future (Mendelsohn et al.,2012).Yifan Ding Jiping Liu Shengzhe Chen Xiao Cheng Zhaojun Zheng 2020Acta Oceanologica Sinica2020,39,8:0
6Variable Learning-Memory Behavior fromπ-Conjugated Ligand to Ligand-Containing Cobalt(II)Complex显示文摘In the information-explosion era,developing novel algorithms and memristive devices has become a promising concept for next-generation capacity enlargement technology.Organic small molecule-based devices displaying superior learning-memory performance have attracted much attention,except for the existence of poor heat-resilience and mediocre conductivity.In this paper,a strategy of transforming an organic-type data-storage material to metal complex is proposed to resolve these intrinsic issues.A pristine NDI-derivative(NIPy)and its corresponding Co(II)complex(CoNIPy)are synthesized for the purpose of electrical property investigation.CoNIPy complex-based memristive device exhibits superior ternary WORM memory performance compared with the binary behavior of NIPy,including>104 s of reading,lower threshold voltage(V_(th)),1:10^(2):10^(5)of OFF/ON1/ON2 current ratio,and long-term stability in heating environment.The variable learning-memory behavior can be attributed to the enhanced ligand-to-metal charge transfer(LMCT)and improved redox activity after the introduction of central metal atom and coordination bond.These studies on material innovation and optimal performance are of great importance not only for environmentally-robust memristive devices but also for practical application of a host of organic electronic devices.Cheng Zhang Mohan Chen Guan Wang Ming Teng Songtao Ling Yanan Wang Zhaojun Su Kun Gao Xinbo Yang Chunlan Ma Yang Li Qichun Zhang 2022Chinese Journal of Chemistry2022,40,19:0
7SPEEDING UP THE CONSTRUCTION OF HIGH-SPEED RAILWAYS IN CHINA显示文摘High-speed railways have the merits of high speed, high transport capacity, low consumption of energy, less pollution, less occupation of land, and greater safety. The development of high-speed railways is suitable for the national conditions in China.The authors suggest that, with the Hu-Ning (Shanghai-Nanjing) section of the Jing-Hu (Beijing-Shanghai) Railway as the starting point, a high-speed dedicated passenger railway line be built to realize the separate transportation of passengers and goods, thus easing the strain on transport in East China, accumulating experience for the future development of high-speed railways, and bringing along the development of high and new technology industries.Cheng Qingguo, Lu Zhaojun and Zhou Jing(China Academy of Railway Sciences, Beijing) 1997Bulletin of the Chinese Academy of Sciences1997,11,2:0
8Effect of Chromium Micro-alloying on the Corrosion Behavior of a Low-carbon Steel Rebar in Simulated Concrete Pore Solutions显示文摘A new low-cost corrosion-resistant rebar(HRB400 R) was designed and fabricated by chromium micro-alloying. The effects of Cr on the passivation and corrosion behavior of this rebar in the simulated concrete pore solutions were studied systematically, and its improved corrosion resistance was revealed. In the Cl--free saturated Ca(OH)_2 solution, the HRB400 R rebar presented nearly the same passive film and similar passivation ability compared to the common carbon steel rebar. In the long-term immersion corrosion test in the Cl--contained Ca(OH)_2 solution, the HRB400 R rebar presented improved corrosion resistance and obvious longer passivation-maintaining period. Micro-alloying of Cr element in the rebar matrix enhanced its corrosion resistance against Cl--attack and retarded the corrosion initiation in the matrix. In the alkaline Na Cl salt spraying test, the HRB400 R rebar also presented obviously lower mass-loss rate. The enrichment of Cr element in the rust layer improved its retardant effect to the penetration of aggressive medium, and decreased the corrosion propagation rate of the rebar.宋丹 蒋金洋 孙伟 MA Han ZHANG Jianchun CHENG Zhaojun JIANG Jinghua AI Zhiyong 2017Journal of Wuhan University of Technology(Materials Science)2017,32,6:0
9Facile immobilization of heparin on bioabsorbable iron via mussel adhesive protein(MAPs)显示文摘Motivated by adhesive proteins in mussels, strategies using dopamine to modified surface have become particularly attractive. In the present work, we developed a novel and convenient method to modify the biodegradable Fe plates with heparin. Iron was first treated by a facile one-step p H-induced polymerization of dopamine, and then a high density heparin was successfully grafted onto the surface via coupling with polydopamine(PDA) active layer. Heparin immobilization contributed much longer blood clotting coagulation time than the pure Fe sample, and hence reduced the risk of thrombosis. Cell viability tests suggested that the heparin modified Fe plates were more favorable to the proliferation of ECV304 cells. In summary, the heparin modified Fe plates with good anti-thrombus properties and inhibiting the proliferation of VSMC cells provide great prospects for biodegradable iron.Xuchen Xu Ming Li Qian Liu Zhaojun Jia Yuying Shi Yan Cheng Yufeng Zheng L.Q. Ruan 2014Progress in Natural Science:Materials International2014,24,5:0
返回顶部 每页显示:
共1页 首页 上一页 第1页 下一页 末页 /1 跳转

网站首页 | 关于我们 | 联系我们 | 产品服务 | 客服中心 | 广告服务 | 版权声明 | 网站联盟 | 友情链接 | 售卡网点

版权所有© 渝B2-20050021-1 渝公网安备 50019002500403号 违法和不良信息举报中心

互联网出版许可证 新出网证(渝)字10号 全国400电话 - 免长途话费