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China Foundry 2023年第3期20卷 207-217页

作者： Bo-wen Zheng Shuai Chen Chun-yu Yue Xue-jian Lin Fu-yu Dong Hong-jun Huang xiao-jiao zuo Yin-xiao Wang xiao-guang Yuan School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

To enhance the performance of in-situ synthesized 6vol.%(Ti C+Ti B)/TC4 titanium matrix composites fabricated by casting,a variety of heat treatment processes were carried *** conducting microstructure observations following various heat treatments,it was found that the composites exhibit a basketweave microstructure,consisting of an α phase and a transformed β *** sizes of(α+β) phases were found to be refined to varying degrees after the heat treatment processes,while the morphology of Ti B remains largely unchanged and Ti C becomes *** testing revealed that all composites subjected to different heat treatments demonstrate a notable increase in ultimate compressive strength as well as a slight improvement in plasticity compared to the as-cast *** results of the tribological performance test indicated that the heat-treated composites exhibit lower average friction coefficient,specific wear rate,and worn surface roughness compared to the as-cast *** the heat treatment processes studied,the composite solution heated at 1,150 °C/1 h followed by air cooling,then 950 °C/1 h followed by air cooling,and finally 500 °C/4 h followed by air cooling,demonstrates the highest levels of hardness,compressive strength,and wear *** improvements are attributed to the combined effects of solid solution strengthening,grain refinement,and the pinning of dislocation slip.

关键词： titanium matrix composites heat treatment mechanical properties tribological properties

A two-terminal all-inorganic perovskite/organic tandem solar cell

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Science Bulletin 2019年第13期64卷 885-887页

作者： Qiang Zeng Ling Liu zuo xiao Fangyang Liu Yong Hua Yongbo Yuan Liming Ding School of Metallurgy and Environment Central South UniversityChangsha 410083China Center for Excellence in Nanoscience (CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication (CAS)National Center for Nanoscience and TechnologyBeijing 100190China School of Materials Science and Engineering Yunnan UniversityKunming 650091China School of Physics & Electronics Central South UniversityChangsha 410083China

Organic-inorganic lead halide perovskite solar cells(PSCs)have been marching rapidly in recent years with power conversion efficiency(PCE)boosting from 3.8%to 24.2%(NREL Best Research-Cell Efficiency Chart,https://***/pv/cell-effi ***,Accessed April 2019).However,these solar cells are not stable at high temperatures due to volatile organic cations[1].Allinorganic perovskites with cesium cation like CsPbI1-xBrx present high thermal stabilities[2].By partially replacing I-with Br-,the bandgap for CsPbI1-xBrx can be tuned from 1.73 to 2.36 eV.

关键词： solar cell perovskite

Prevalence of polymyxin-induced nephrotoxicity and its predictors in critically ill adult patients:A meta-analysis

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World Journal of Clinical Cases 2022年第31期10卷 11466-11485页

作者： Jiang-Lin Wang Bi-xiao Xiang xiao-Li Song Rui-Man Que xiao-Cong zuo Yue-Liang Xie Department of Pharmacy The Third Xiangya Hospital of Central South UniversityChangsha 410013Hunan ProvinceChina Department of Pharmacy Sanya Central HospitalSanya 572000Hainan ProvinceChina

BACKGROUND Polymyxin-induced nephrotoxicity is a major safety concern in clinical practice due to long-term adverse outcomes and high *** To conducted a systematic review and meta-analysis of the prevalence and potential predictors of polymyxin-induced nephrotoxicity in adult intensive care unit(ICU)*** PubMed,EMBASE,the Cochrane Library and Reference Citation Analysis database were searched for relevant studies from inception through May 30,*** pooled prevalence of polymyxin-induced nephrotoxicity and pooled risk ratios of associated factors were analysed using a random-effects or fixed-effects model by Stata SE ***,subgroup analyses and meta-regression were conducted to assess *** A total of 89 studies involving 12234 critically ill adult patients were included in the *** overall pooled incidence of polymyxin-induced nephrotoxicity was 34.8%.The pooled prevalence of colistin-induced nephrotoxicity was not higher than that of polymyxin B(PMB)-induced *** subgroup analyses showed that nephrotoxicity was significantly associated with dosing interval,nephrotoxicity criteria,age,publication year,study quality and sample size,which were confirmed in the univariable meta-regression *** was significantly increased when the total daily dose was divided into 2 doses but not 3 or 4 ***,older age,the presence of sepsis or septic shock,hypoalbuminemia,and concomitant vancomycin or vasopressor use were independent risk factors for polymyxin-induced nephrotoxicity,while an elevated baseline glomerular filtration rate was a protective factor against colistin-induced *** Our findings indicated that the incidence of polymyxin-induced nephrotoxicity among ICU patients was *** emphasizes the importance of additional efforts to manage ICU patients receiving polymyxins to decrease the risk of adverse outcomes.

关键词： Polymyxins Nephrotoxicity Critically ill adult patients Risk factors Meta-analysis

Erosion behavior and failure mechanism of Ti/TiAlN multilayer coatings eroded by silica sand and glass beads

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Journal of Materials Science & Technology 2021年第21期80卷 179-190页

作者： Jintao Shuai xiao zuo Zhenyu Wang Lili Sun Rende Chen Li Wang Aiying Wang Peiling Ke Key Laboratory of Marine Materials and Related Technologies Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China Ningbo Institute of Industrial Technology Ningbo315201China

Severe erosion by hard particles is a crucial problem to engine blades when aircraft take off and land in harsh environments, especially for the developed lightweight titanium alloy components. Here, we deposited the Ti/TiAlN multilayer coatings with various cycles on Ti–6 Al–4 V substrates by a home-made hybrid multisource cathodic arc system. The effects of the silica sand and glass beads on erosion behavior of the coatings were focused. Results showed that the Ti/TiAlN multilayer coatings eroded by the silica sand exhibited the predominant "layer by layer" failure mechanism. In particular, increasing the number of cycles led to the dramatic increase in erosion rate for Ti/TiAlN multilayer coatings, due to the deterioration of their mechanical properties. Different from the silica sand case, however, the erosion rate of the coatings treated by glass beads indicated faint dependence upon the number of cycles, where the coating failure was dominated by the "piece by piece" failure mechanism. Noted that the Ti layers along with the formed interfaces enhanced the erosion resistance of the coatings, although the failure mechanisms were differently eroded by silica sand and glass beads. Meanwhile, the Ti layers and interfaces hindered the propagation of radial cracks and restrained the lateral cracks within one single TiAlN layer.

关键词： Ti/TiAlN multilayer coating Erosion resistance Microstructure Failure mechanism

MONITORING OF ENERGETIC PARTICLE ENVIRONMENT INSIDE THE CHINA-BRAZIL EARTH RESOURCE SATELLITE

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空间科学学报 2002年第Z1期22卷 57-63页

作者： xiao zuo ZOU Hong ZOU Jiqing ZHONG Weiying Department of Geophysics Peking University Beijing 100871 P.R. China Department of Geophysics Peking University Beijing 100871 P.R. China Department of Geophysics Peking University Beijing 100871 P.R. China Department of Geophysics Peking University Beijing 100871 P.R. China

On 14 October 1999, the Chinese-Brazil earth resource satellite (CBERS-1) was launched in China. On board of the satellite there was an instrument designed at Peking University to detect the energetic particle radiation inside the satellite so the radiation fluxes of energetic particles in the cabin can be monitored continuously. Inside a satellite cabin, radiation environment consists of ether penetrated energetic particles or secondary radiation from satellite materials due to the interactions with primary cosmic *** of the detectors are twofold, to monitor the particle radiation in the cabin and also to study the space radiation environment The data can be used to study the radiation environment and their effects on the electronics inside the satelhte cabin. On the other hand, the data are useful in study of geo-space energetic particle events such as solar proton events, particle precipitation and variations of the radiation belt since there should be some correlation between the radiation situation inside and outside the *** instrument consists of two semi-conductor detectors for protons and electrons respectively. Each detector has two channels of energy ranges. They are 0.5-2MeV and ≥2MeV for electrons and 5-30MeV and 30-60MeV for protons. Counting rate for all channels are up to 104/(cm2@s)and power consumption is about 2.5 W. There are also the additional functions of CMOS TID (total integrated dose) effect and direct SEU monitoring. The data of CBMC was first sent back on Oct. 17 1999 and it's almost three years from then on. The detector has been working normally and the quality of data is *** preliminary results of data analysis of CBMC not only reveal the effects of polar particle precipitation and radiation belt on radiation environment inside a satellite, but also show some important features of the geo-space energetic particle *** one of the most important parameters of space weather, the energetic charged particles h

关键词： Earth's radiation belts, Space energetic particles, Space weather

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Journal of Semiconductors 2021年第2期42卷 13-16页

作者： Ling Liu zuo xiao Chuantian zuo Liming Ding Center for Excellence in Nanoscience(CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

SUPPORTING INFORMATION Experimental section Materials characterization The thicknesses of the films were measured by using a KLA Tencor D-120 *** spectra for the films were recorded on a Shimadzu UV-1800 *** SEM image... 详细信息

关键词： perovskite Zeiss films

The seasonal dependence of cycle slip occurrence of GPS data over China low latitude region

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Science China(Technological Sciences) 2007年第4期50卷 422-429页

作者： ZHANG DongHe FENG Man xiao zuo HAO YongQiang SHI LiQin YANG GuangLin SUO YuCheng Department of Geophysics Peking UniversityBeijing 100871China Center for Space Science and Applied Research Chinese Academy of SciencesBeijing 100080China National Forecasting Center for Space Weather Beijing 100080China China Research Institute for Radio Propagation Xinxiang 453003China

The relationship of daily accumulated cycle slip occurrence with the season is analyzed using the GPS data observed in six GPS stations located in China low latitude region in 2001. It is found that the seasonal dependence of cycle slip oc-currence is evident. The cycle slip mainly occurs during the periods of two equinox months (March to May and September to October), and some correlative changes of the cycle slip occurrences over all six stations are exhibited in some special days. Considering the diurnal dependence of cycle slip, it can be inferred that the cycle slip occurrence with certain elevation limitation is related with the iono-spheric irregularities over this region.

关键词： GPS cycle slip ionospheric irregularities scintillation carrier phase

Reduction Behaviors of Pellets Under Different Reducing Potentials

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Journal of Iron and Steel Research International 2013年第12期20卷 12-18页

作者： zuo xiao-jian WANG Jing-song AN Xiu-wei SHE Xue-feng XUE Qing-guo State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

Owing to the change of gas composition in top gas recycling-oxygen blast furnaces compared with tradi- tional blast furnace, many attentions are attracted to the research on iron oxide reduction again. In order to study the influence of H2 and CO on the reduction behavior of pellets, experiments were conducted with H2-N2, CO N2 or H2-CO gas mixtures at 1 173 K by measuring the mass loss, respectively. It was found that the reduction degree in creased with increasing the ratio of H2 or CO in the gas mixture, but the reduction with hydrogen was faster than that with carbon monoxide. The reduction degree could reach 96. 720/00 after 65 rain for the reduction with 50~ H2 ＋ 50% N2, while it is only 53.37~ for the reduction with 50~ COq-50~ N2. The addition of hydrogen to carbon monoxide will accelerate the reduction because the hydrogen molecules are more easily chemisorbed and reacted with iron oxide than carbon monoxide. A scanning electron microscope was used to characterize the structures of reduced samples. Dense structure of iron was obtained in the reduction with hydrogen while the structure of iron showed many small fragments for the reduction with carbon monoxide. At the later stage of reduction with the gas mixtures containing carbon monoxide, the reduction curves showed a descending trend because the rate of carbon deposition caused by the thermal decomposition of carbon monoxide was faster than the rate of oxygen loss. Compared with the reduction with CO-N2 and H2 CO gas mixtures, H2 gas could enhance the carbon deposition while N2 gas would re- duce this phenomenon. The results of X-ray diffraction and chemical analysis demonstrated that the carbons are mainly in the form of cementite （FeaC） and graphite in reduced sample.

关键词： reduction pellet hydrogen carbon monoxide carbon deposition

Analysis on Initial Defects Based on Mechanical State of Meniscus Shell

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Journal of Iron and Steel Research International 2015年第12期22卷 1085-1090页

作者： Xiang-ning MENG Ren-gan LIN Jie YANG xiao-jing zuo Miao-yong ZHU School of Materials and Metallurgy Northeastern University

The meniscus shell plays an important role in slab quality and process operation for continuously cast steel. One decisive reason is initial solidifying shell and growing dendrite under the mechanical stress caused by mold oscil- lation and liquid steel flow to generate disturbance of casting. The mechanical state of meniscus shell was analyzed using mathematical models in combination with thermo-physical properties and flow rate of steel to shed light on the formation of initial defects. The results show that the mold oscillation is a critical factor on the initial crack formation because the periodic stress makes the shell bending. The formed crack may also expand and propagate due to the fol- lowing secondary cooling and straightening behavior. The primary dendrite has high possibility to be broken by fluid flow in the solidification front to lead to the non-uniform thickness of solidifying shell. The inter-dendrite bridging is also likely to be formed to produce other internal defects, such as air hole and solute enrichment in the residual mol- ten steel located in the bridging area.

关键词： continuous casting mold oscillationl meniscus shell initial defect mathematical model

Reduction Behavior of Pellet under Simulated Oxygen Blast Furnace Condition

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Journal of Iron and Steel Research International 2015年第2期22卷 115-120页

作者： Hua-jie ZHANG Jing-song WANG Xiu-wei AN xiao-jian zuo Qing-guo XUE State Key Laboratory of Advanced Metallurgy School of Metallurgical and Ecological EngineeringUniversity of Science and Technology Beijing

The reduction behavior of pellet was researched through the programming apparatus under simulated con- ditions of oxygen blast furnace （OBF） and traditional blast furnace （T-BF）. The results indicated that compared with traditional blast furnace, the reduction starting temperature of pellet decreased by 60 ℃ under oxygen blast furnace condition. The reduction degree of pellet could almost reach 100% under oxygen blast furnace condition when the temperature reached 1100 ℃, whereas it was only 82.49% in traditional blast furnace. The content of carbon in pel- let of oxygen blast furnace was about 5 times more than that of traditional blast furnace. In addition, the microstruc- ture at the periphery and core of pellets after reaction was characterized by means of SEM and EDS.

关键词： oxygen blast furnace programming reduction reduction behavior carbon deposition