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1High-entropy ceramics:Present status,challenges,and a look forward显示文摘High-entropy ceramics (HECs) are solid solutions of inorganic compounds with one or more Wyckoff sites shared by equal or near-equal atomic ratios of multi-principal elements.Although in the infant stage,the emerging of this new family of materials has brought new opportunities for material design and property tailoring.Distinct from metals,the diversity in crystal structure and electronic structure of ceramics provides huge space for properties tuning through band structure engineering and phonon engineering.Aside from strengthening,hardening,and low thermal conductivity that have already been found in high-entropy alloys,new properties like colossal dielectric constant,super ionic conductivity,severe anisotropic thermal expansion coefficient,strong electromagnetic wave absorption,etc.,have been discovered in HECs.As a response to the rapid development in this nascent field,this article gives a comprehensive review on the structure features,theoretical methods for stability and property prediction,processing routes,novel properties,and prospective applications of HECs.The challenges on processing,characterization,and property predictions are also emphasized.Finally,future directions for new material exploration,novel processing,fundamental understanding,in-depth characterization,and database assessments are given.Huimin XIANG Yan XING Fu-zhi DAI Hongjie WANG Lei SU Lei MIAO Guojun ZHANG Yiguang WANG Xiwei QI Lei YAO Hailong WANG Biao ZHAO Jianqiang LI Yanchun ZHOU 2021Journal of Advanced Ceramics2021,10,3:28
2Whole-genome sequencing of 508 patients identifies key molecular features associated with poor prognosis in esophageal squamous cell carcinoma显示文摘Esophageal squamous cell carcinoma(ESCC)is a poor-prognosis cancer type with limited understanding of its molecular etiology.Using 508 ESCC genomes,we identified five novel significantly mutated genes and uncovered mutational signature clusters associated with metastasis and patients’outcomes.Several functional assays implicated that NFE2L2 may act as a tumor suppressor in ESCC and that mutations in NFE2L2 probably impaired its tumor-suppressive function,or even conferred oncogenic activities.Additionally,we found that the NFE2L2 mutations were significantly associated with worse prognosis of ESCC.We also identified potential noncoding driver mutations including hotspot mutations in the promoter region of SLC35E2 that were correlated with worse survival.Approximately 5.9%and 15.2%of patients had high tumor mutation burden or actionable mutations,respectively,and may benefit from immunotherapy or targeted therapies.We found clinically relevant coding and noncoding genomic alterations and revealed three major subtypes that robustly predicted patients’outcomes.Collectively,we report the largest dataset of genomic profiling of ESCC useful for developing ESCC-specific biomarkers for diagnosis and treatment.Yongping Cui Hongyan Chen Ruibin Xi Heyang Cui Yahui Zhao Enwei Xu Ting Yan Xiaomei Lu Furong Huang Pengzhou Kong Yang Li Xiaolin Zhu Jiawei Wang Wenjie Zhu Jie Wang Yanchun Ma Yong Zhou Shiping Guo Ling Zhang Yiqian Liu Bin Wang Yanfeng Xi Ruifang Sun Xiao Yu Yuanfang Zhai Fang Wang Jian Yang Bin Yang Caixia Cheng Jing Liu Bin Song Hongyi Li Yi Wang Yingchun Zhang Xiaolong Cheng Qimin Zhan Yanhong Li Zhihua Liu-Show 2020Cell Research2020,30,10:19
3Microstructure and properties of Al_2O_3-13%TiO_2 coatings sprayed using nanostructured powders显示文摘The microstructure and wear performance of Al2O3-13% TiO2 coatings prepared by plasma spraying of agglom- erated nanoparticle powders were investigated. SEM analysis showed that the as-sprayed Al2O3-TiO2 coatings comprise of two kinds of typical region: fully melted region and unmelted/partially melted nanostructured region, which is different than the conventional coating with lamellar structure. It is shown that the microhardness of the nanostructured coatings was about 15%-30% higher than that of the conventional coating and the wear resistance is significantly improved, especially under a high wear load. The nanostructured coating sprayed at a lower power shows a lower wear resistance than the coat- ings produced at a higher power, because of the presence of pores and microstructural defects which are detrimental to the fracture toughness of the coatings.ZHANG Jianxin HE Jining DONG Yanchun LI Xiangzhi YAN Dianran 2007Rare Metals2007,26,4:18
4Layer-by-layer deposition of bioactive layers on magnesium alloy stent materials to improve corrosion resistance and biocompatibility显示文摘Magnesium alloy is considered as one of the ideal cardiovascular stent materials owing to its good mechanical properties and biodegradability.However,the in vivo rapid degradation rate and the insufficient biocompatibility restrict its clinical applications.In this study,the magnesium alloy(AZ31B)was modified by combining the surface chemical treatment and in-situ self-assembly of 16-phosphonyl-hexadecanoic acid,followed by the immobilization of chitosan-functionalized graphene oxide(GOCS).Heparin(Hep)and GOCS were alternatively immobilized on the GOCS-modified surface through layer by layer(LBL)to construct the GOCS/Hep bioactive multilayer coating,and the corrosion resistance and biocompatibility were extensively explored.The results showed that the GOCS/Hep bioactive multilayer coating can endow magnesium alloys with an excellent in vitro corrosion resistance.The GOCS/Hep multilayer coating can significantly reduce the hemolysis rate and the platelet adhesion and activation,resulting in an excellent blood compatibility.In addition,the multilayer coating can not only enhance the adhesion and proliferation of the endothelial cells,but also promote the vascular endothelial growth factor(VEGF)and nitric oxide(NO)expression of the attached endothelial cells on the surfaces.Therefore,the method of the present study can be used to simultaneously control the corrosion resistance and improve the biocompatibility of the magnesium alloys,which is expected to promote the application of magnesium alloys in biomaterials or medical devices,especially cardiovascular stent.Fan Gao Youdong Hu Guicai Li Sen Liu Li Quan Zhongmei Yang Yanchun Wei Changjiang Pan 2020Bioactive Materials2020,5,3:12
5Microstructure and mechanical properties of Mg-4.0Zn alloy reinforced by NiO-coated CNTs显示文摘Mg-4.0Zn alloy composite reinforced by NiO-coated CNTs(NiO@CNTs) was synthesized by combining ball-milling and a casting process. The yield strength(YS) and elongation to failure of the composite were dramatically increased by 44.9% and 38.6%, respectively, compared to its alloy counterpart. The significantly enhanced mechanical properties of the as-synthesized composite are mainly ascribed to an improved interfacial bond, grain refinement and good dispersion of CNTs in the matrix via. coating NiO on CNTs.It is shown that the NiO-nanolayer on the CNTs significantly enhances the interfacial bonding strength and effectively prevents the agglomeration of CNTs. NiO@CNTs are, therefore, expected to be a highly sustainable and dispersible reinforcement for magnesium matrix composites with superior performance.Qiuhong Yuan Xiaoshu Zeng Yanchun Wang Lan Luo Yan Ding Dejiang Li Yong Liu 2017Journal of Materials Science & Technology2017,33,5:8
6Comprehensive reform of community health service in east,middle and west regions of China:from patients’perspective显示文摘Objectives:To analyze the satisfaction of patients with community health service(CHS)and the changes of the CHS delivered before and after the new health reform in different regions of China,and to put forward relevant policy recommendations for CHS development.Methods:Twelve community health centers were selected by random sampling in each of the eight typical cities in the east,middle and west regions of China.Questionnaire survey was conducted among patients visiting these institutions during daily work hours.Results:The proportions of the participants who stated that the medical environment,service attitude and medical skills of the doctors were improved were higher in the west region than those of the east and middle regions;but the percentage of patients who held that the drug price had lowered was higher in the east region than those of the middle and west region,the differences were of statistical significance(P<0.0125).The patients’satisfaction rates with medical environment,service attitude,and technical skills of the medical staff in the west region were 88.9%,91.5%and 81.6%respectively,which were higher than those in the east and middle regions.In the east region,the satisfaction rate with the reimbursement for this visit was 58.5%,which was highest among the three regions;in the west region,patients’satisfaction rates with drug types and preventive care were 51.5%and 65.9%,respectively,which was significantly higher than those in the east and middle regions(P<0.0125).As recommended by the participants,the top three aspects of health services that need to be improved were drug type and quality(25.3%),drug prices(21.8%)and technical skills(18.2%)in the east region;infrastructure(28.2%),drug prices(21.8%)and drug types and quality(21.2%)in the middle region;infrastructure(30.8%),drug types and quality(28.1%)and reimbursement(27.9%)in the west region.Conclusions:The comprehensive CHS reform should take the opinions of patients into account;essential drug system should be consolidated continually;and the reform of the payment system should be promoted by actively cooperating with the health insurance organizations.JIANGMEI QIN YANCHUN ZHANG LIFANG ZHANG LIQUN LIU WEI ZHOU CAILING LIU LIKUN WANG JING LI 2013Family Medicine and Community Health2013,1,2:6
7Similar simulation study on the deformation and failure of surrounding rock of a large section chamber group under dynamic loading显示文摘Large and super-large section chamber groups in coal mines are frequently affected by dynamic loads resulting from production activities such as roadway driving and blasting.The stability of the surrounding rock is poor,and it is difficult to control.In this paper,a similar simulation test was used to study the deformation and evolution laws of the surrounding rock of a triangle-shaped chamber group under different dynamic loads.The results showed that under dynamic loading,the vertical stress of the surrounding rock of the chamber group increased in an oscillatory form.The maximum stress concentration coefficient reached 4.09.The damage degree of the roof was greater than that of the two sides.The deformation of the roof was approximately 1.2 times that of the two sides.For the chamber closer to the power source,the stress oscillation amplitude of the surrounding rock was larger,and the failure was more serious.The force of the anchorage structure showed a phased increasing characteristic;additionally,the force of the anchorage structure on the adjacent side of the chambers was greater than that on the other side.This study reveals the deformation and failure evolution laws of the surrounding rock of large section chamber groups under dynamic loading.Xuesheng Liu Shilin Song Yunliang Tan Deyuan Fan Jianguo Ning Xuebin Li Yanchun Yin 2021International Journal of Mining Science and Technology2021,31,3:6
8In-situ Synthesis of Ti_3AlC2/TiC-Al_2O_3 Composite from TiO_2-Al-C System显示文摘Ti_3AlC_2/TiC-Al_2O_3 合成被一个燃烧反应 inTiO_2-AI-C 系统综合。在产品上的原料的作文的效果是 investigated.Ti_3AlC_2/TiC-Al_2O_3 合成在 TiO_2 的臼齿的比率被获得: AI : 为 3TiO_2-5AI-2C 系统的 C=3.0:5.0~5.1:1.8~2.0.The 反应路径被建议。AI_3Ti, Ti_2O_3, TiO,和 delta-AI_2O_3are 发现了是过渡阶段。最后,在 ~ 的 Ti_3AlC_2/TiC-Al_2O_3 合成形式 900 deg Cof 炉子温度。从 3TiO_2-5AI-2C 的将近稠密的样品的测量 Vickers 坚硬,破裂坚韧,和曲折力量是 13.3+-1.1 GPa, 5.8+-0.3 MPa 中心点 m^(1/2 ) , and466 ± 3 9 MPa 分别地。Jixin CHEN Jialin LI Yanchun ZHOU 2006Journal of Materials Science & Technology2006,22,4:6
9Recent progress in organic solar cells(PartⅠmaterial science)显示文摘During past several years,the photovoltaic performances of organic solar cells(OSCs)have achieved rapid progress with power conversion efficiencies(PCEs)over 18%,demonstrating a great practical application prospect.The development of material science including conjugated polymer donors,oligomer-like organic molecule donors,fused and nonfused ring acceptors,polymer acceptors,single-component organic solar cells and water/alcohol soluble interface materials are the key research topics in OSC field.Herein,the recent progress of these aspects is systematically summarized.Meanwhile,the current problems and future development are also discussed.Yahui Liu Bowen Liu Chang-Qi Ma Fei Huang Guitao Feng Hongzheng Chen Jianhui Hou Lingpeng Yan Qingya Wei Qun Luo Qinye Bao Wei Ma Wei Liu Weiwei Li Xiangjian Wan Xiaotian Hu Yanchun Han Yaowen Li Yinhua Zhou Yingping Zou Yiwang Chen Yongfang Li Yongsheng Chen Zheng Tang Zhicheng Hu Zhi-Guo Zhang Zhishan Bo 2022Science China Chemistry2022,65,2:5
10Synthesis,Microstructure,and Property of Cr_2AlC显示文摘Cr_2AlC is an unusual layered ternary ceramic that combines the merits of both metals and ceramics.The salient properties of Cr_2AlC are strongly related to its bonding characteristics and microstructures.Synthesis, microstructure,and property of Cr_2AlC are reviewed in this paper.First,theoretical calculations and physical properties are introduced.Then,the processing of Cr_2AlC ceramic in both bulk form and thin films and their basic mechanical properties are summarized.Atomic-scale characterizations of Cr_2AlC,as well as the microstructural relationships among Cr_2AlC,Al_8Cr_5,and AlCr_2 were achieved using a series of transmission electron microscopy(TEM)techniques.Moreover,high-temperature oxidation and hot corrosion behaviors of Cr_2AlC were investigated by means of thermogravimetric analysis,X-ray diffraction,Raman spectroscopy, scanning electron microscopy,and TEM.Mechanism of the excellent high-temperature corrosion resistance of Cr_2AlC is discussed based on systematic microstructural analyses.Finally,concise conclusions are drawn.Zhijun LIN Yanchun ZHOU Meishuan LI 2007Journal of Materials Science & Technology2007,23,6:5
11Detection and Classification of Power Quality Disturbances in Distribution Networks Based on VMD and DFA显示文摘In this paper,a novel algorithm is proposed to detect and classify the power quality(PQ)disturbances for distribution networks with distributed generation.First,a distribution system with photovoltaic and wind power generation is built as a test platform.Then,nine types of power quality disturbances in the distribution network are decomposed by variational mode decomposition(VMD)and the noise is filtered.Meanwhile,the mode functions containing characteristic information are extracted as input signals of detrended fluctuation analysis(DFA).Power quality disturbances are classified from the view of their distributed energy operational status,and three types of windows are set up to deal with different frequency disturbances.The two-dimensional and three-dimensional scatter plots of each type under three windows are depicted,and the criteria are determined to distinguish the disturbances under the different operating conditions.The simulations show that the algorithm is simpler,more accurate and feasible.It provides an approach for online real-time detection of embedded systems.Yanchun Xu Yongkang Gao Zhenhua Li Mi Lu 2020CSEE Journal of Power and Energy Systems2020,6,1:4
12Application of high-throughput first-principles calculations in ceramic innovation显示文摘Recent technical progress in the industry has led to an urgent requirement on new materials with enhanced multi-properties.To meet this multi-property requirement,the materials consisting of three and more elements have attracted increasing attention.However,facing to the nearly unknown huge multi-component materials system,the traditional trial and error method cannot provide sufficient data efficiently.Therefore,an efficient material innovation strategy is significant.The first-principles calculation based on the density functional theory is a powerful tool for both the accurate prediction of material properties and the identification of its underlying thermodynamics and dynamics.At the same time,the advances of computational methods and computer calculation abilities that are orders of magnitude faster than before make the high throughput first-principles calculations popular.At present,the simulation-assisted material design has become a main branch in the material research field and a great many successes have been made.In this article,the advances of the high throughput first-principles calculations are reviewed to show the achievements of the first-principles calculations and guide the future directions of its applications in ceramics.Bin Liu Juanli Zhao Yuchen Liu Jianqi Xi Qian Li Huimin Xiang Yanchun Zhou 2021Journal of Materials Science & Technology2021,,29:4
13Age, estimated glomerular filtration rate and ejection fraction score predicts contrast-induced acute kidney injury in patients with diabetes and chronic kidney disease: insight from the TRACK-D study显示文摘Li Jing Li Yi Wang Xiaozeng Yang Shuguang Gao Chuanyu Zhang Zheng Yang Chengming Jing Quanming Wang Shouli Ma Yingyan Wang Zulu Liang Yanchun Han Yaling 2014Chinese Medical Journal2014,,12:3
14Flexible Operation Mode of Coal-fired Power Unit Coupling with Heat Storage of Extracted Reheat Steam显示文摘In order to provide more grid space for the renewable energy power,the traditional coal-fired power unit should be operated flexibility,especially achieved the deep peak shaving capacity.In this paper,a new scheme using the reheat steam extraction is proposed to further reduce the load far below 50%rated power.Two flexible operation modes of increasing power output mode and reducing fuel mode are proposed in heat discharging process.A 600 MW coal-fired power unit with 50%rated power is chosen as the research model.The results show that the power output is decreased from 300.03 MW to 210.07 MW when the extracted reheat steam flow rate is 270.70 t·h^(-1),which increases the deep peak shaving capacity by 15%rated power.The deep peak shaving time and the thermal efficiency are 7.63 h·d^(-1)and 36.91%respectively for the increasing power output mode,and they are 7.24 h·d^(-1)and 36.58%respectively for the reducing fuel mode.The increasing power output mode has the advantages of higher deep peak shaving time and the thermal efficiency,which is recommended as the preferred scheme for the flexible operation of the coal-fired power unit.WEI Haijiao LU Yuanwei YANG Yanchun ZHANG Cancan WU Yuting LI Weidong ZHAO Dongming 2022Journal of Thermal Science2022,31,2:3
15Theoretical prediction on mechanical and thermal properties of a promising thermal barrier material:Y_(4)Al_(2)O_(9)显示文摘The mechanical and thermal properties of Y_(4)Al_(2)O_(9)were predicted using a combination of first-principles and chemical bond theory(CBT)calculations.Density functional theory(DFT)computations were performed for the structural,mechanical,and thermal properties,and the results were confirmed by chemical bond theory.Based on the calculated equilibrium crystal structure,heterogeneous bonding nature has been revealed,i.e.,Al-O bonds are stronger than Y-O bonds.Low second-order elastic constants c44,c55,and c66 demonstrate the low shear deformation resistance.Low G/B ratio suggests that Y_(4)Al_(2)O_(9)is a damage tolerant ceramic.Y_(4)Al_(2)O_(9)shows anisotropy in elastic behavior based on the discussion of direction dependence of Young’s modulus.The hardness is predicted to be 10.2 GPa from calculated elastic moduli.The thermal expansion coefficient(TEC)calculated by chemical bond theory is 7.51×10^(-6)K^(-1).In addition,the minimum thermal conductivity of Y_(4)Al_(2)O_(9)is estimated to be 1.13 W·m^(-1)·K^(-1),and the thermal conductivity decreases with temperature as 1305.6/T.Yanchun ZHOU Huimin XIANG Xinpo LU Zhihai FENG Zhongping LI 2015Journal of Advanced Ceramics2015,4,2:3
16Recent progress in organic solar cells(PartⅡdevice engineering)显示文摘1 Introduction Organic solar cells(OSCs)belong to a multidisciplinary field composed of chemistry,materials science,physics,engineering,etc.For a better reviewing of this field,we briefly divide the research field of OSCs into two parts:material science and device engineering.In our previous review,the material science part of OSCs,including conjugated polymer donors and acceptors,small molecular donors and acceptors.Yahui Liu Bowen Liu Chang-Qi Ma Fei Huang Guitao Feng Hongzheng Chen Jianhui Hou Lingpeng Yan Qingya Wei Qun Luo Qinye Bao Wei Ma Wei Liu Weiwei Li Xiangjian Wan Xiaotian Hu Yanchun Han Yaowen Li Yinhua Zhou Yingping Zou Yiwang Chen Yuqiang Liu Lei Meng Yongfang Li Yongsheng Chen Zheng Tang Zhicheng Hu Zhi-Guo Zhang Zhishan Bo 2022Science China Chemistry2022,65,8:3
17Effect of cooling rate on plastic deformation of Zr-based bulk metallic glassesChunyan Li Shengzhong Kou Yanchun Zhao Guangqiao Liu Yutian Ding 2012Progress in Natural Science:Materials International2012,22,1:3
18(Ca,Sr,Ba)ZrO_(3):A promising entropy-stabilized ceramic for titanium alloys smelting显示文摘A novel entropy-stabilized(ES)(Ca,Sr,Ba)ZrO_(3) ceramic has been designed and synthesized by pressureless sintering of CaZr03,SrZr03 and BaZr03 powders mixtures at 1450℃,1500℃and 1550℃for 3 h.X-ray diffraction,scanning electron microscopy and transmission electron microscopy analyses collectively indicate that a single solid solution is formed with a homogeneous distribution of metal elements after sintering at 1550℃.The relative density and hardness of the ES(Ca,Sr,Ba)ZrO_(3) ceramic sintered at 1550℃are 97.79%and 10.840.33 GPa,re s pectively.This ES(Ca,Sr,Ba)ZrO_(3) exhibits lower thermal conductivity from 373 K to 1073 K than their constituting zirconates,CaZrO_(3),SrZrO_(3) and BaZrO_(3).Most importantly,the ES(Ca,Sr,Ba)ZrO_(3) ceramic possesses good corrosion resistance to TiNi alloy melt and no distinct reaction layer exists between TiNi alloy and ES(Ca,Sr,Ba)ZrO_(3) ceramic in the contact region.The combination of these properties indicates that ES(Ca,Sr,Ba)ZrO_(3) ceramic is promising for use as a novel crucible material for the melting of titanium alloys.Shuaihang Qiu Mingliang Li Gang Shao Hailong Wang Jinpeng Zhu Wen Liu Bingbing Fan Hongliang Xu Hongxia Lu Yanchun Zhou Rui Zhang 2021Journal of Materials Science & Technology2021,,6:3
19Simultaneous polyandry and heteropaternity in tiger(Panthera tigris altaica):Implications for conservation of genetic diversity in captive populations of felids显示文摘Male tigers(Panthera tigris altaica) in captivity copulate alternatively with an estrous female,suggesting a potential for heteropaternity as an effective reproductive strategy to maximize genetic diversity of offspring.We analyzed microsatellites to test and compare the genetic output of multiple male mating(simultaneous polyandry) and single male mating(monogamy) with a female in a captive population.Simultaneous polyandry resulted in heteropaternity in 66.7% observed litters.No significant differences between parental populations and between offspring populations were detected in the number of alleles(A),expected heterozygosity(H e),number of effective alleles(N e) per locus and standard individual heterozygosity(SH)(P>0.05 for all 4 indexes).Comparisons showed no significant reduction of A,H o,H e and SH from parental population to offspring population for the two mating modes(P>0.05) except for SH in polyandrous families(P=0.029).However,such reduction was equivalent to single mating families when the influence of relatedness was eliminated using effective SH(E SH)(P>0.05).These results highlight an alternative strategy for managing captive populations of tiger and other wild felids in which animals are combined at one location allowing for copulation by multiple males to encourage heteropaternity in favor of maintained genetic diversity among offspring.LIU Dan MA Yue LI HuiYi XU YanChun ZHANG Yan DAHMER Thomas BAI SuYing WANG Jian 2013Chinese Science Bulletin2013,58,17:3
20Application of Preoperative Visits during the Perioperative Period of Ophthalmic Surgery显示文摘Purpose:.To evaluate the effect of preoperative visits on patients′ psychology, physiology, and behavior during the perioperative period of eye surgery under local anesthesia, with the aim of enhancing patients′ cooperation with the surgery and improving their degree of satisfaction.Methods:.A total of 240 patients scheduled to undergo eye surgery between August and October 2013 were randomly divided into an observation(n = 120) and a control(n = 120)group..Patients in the observation group attended preoperative visits with nurses and received conventional nursing care. The control group received only conventional nursing.Results:.The Zung self-rating anxiety scale(SAS) scores were significantly lower in patients from the observation group than in the control group(P<0.05). Surgeons operating on the observation group were more satisfied with their patients′ cooperation with the surgery than were surgeons operating on the controls(P<0.01). Patients in the observation group had a significantly higher degree of satisfaction in terms of work efficiency in the operating room(P<0.01).Conclusion:.Preoperative visits by patients scheduled to undergo eye surgery can effectively mitigate preoperative anxiety in those patients,.build up a positive attitude toward the upcoming surgery,.instruct the patients to coordinate with the surgery,.enhance surgical safety,.and improve the patients′degree of satisfaction regarding the nursing care in the operating room.Dan Wu Yingjun Chen Yanchun Wu Haihuan Li Miaoyu Fu Yanchan Liu 2015Eye Science2015,30,2:3
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