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Review of laser powder bed fusion(LPBF)fabricated Ti-6Al-4V:process,post-process treatment,microstructure,and property

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Light(Advanced Manufacturing) 2021年第3期2卷 56-75页

作者： sheng Cao Yichao Zou chao Voon Samuel Lim Xinhua wu department of Materials The University of ManchesterOxford RoadManchesterM139PLUK Monash Centre for Additive Manufacturing Monash UniversityVIC 3800Australia department of Materials Science and Engineering Monash UniversityVIC 3800

Laser powder bed fusion(LPBF)is a timely important additive manufacturing technique that offers many opportunities for fabricating three-dimensional complex shaped components at a high resolution with short lead *** technique has been extensively employed in manufacturing Ti-6Al-4V parts for aerospace and biomedical ***,many challenges,including poor surface quality,porosity,anisotropy in microstructure and property,and difficulty in tailoring microstructure,still *** this paper,we review the recent progress in post-process treatment and its influence on the microstructure evolution and material performance,including tensile,fatigue,fracture toughness,creep,and corrosion *** contradictions in simultaneously achieving high strength/ductility and strength/fracture toughness/creep resistance have been ***,research gaps in understanding the effects of the emerging bi-modal microstructure on fatigue properties and fracture toughness require further investigation.

关键词： microstructure toughness creep

Elevated high sensitive C-reactive protein and apelin levels after percutaneous coronary intervention and drug-eluting stent implantation

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Journal of zhejiang university-Science B(Biomedicine & Biotechnology) 2010年第8期11卷 548-552页

作者： Xin DU Jun-ping KANG Jia-hui wu Qiang LV chao-shu TANG Chang-sheng MA Cardiovascular Division Beijing Anzhen Hospital Copital Medical University Beijing 100029 China department of Physiology and Pathophysiology School of Basic Medical Sciences Peking University Beijing 100083 China

Objective:Percutaneous coronary intervention(PCI) triggers an acute inflammatory response,while sirolimus is known to have anti-inflammatory properties;the inflammatory system response to PCI after sirolimus-eluting stent placement remains *** purpose of this study is to determine the changes in high sensitive C-reactive protein(hs-CRP) and apelin after PCI procedure and drug-eluting stent implantation in patients with and without reduced left ventricular systolic ***:Forty-eight consecutive patients undergoing PCI at the Beijing Anzhen Hospital between July and September 2006 were ***-eluting stents were employed in all *** samples were drawn immediately before and 24 h after the *** hs-CRP and apelin levels were determined by enzyme ***:Paired t-test revealed a significant increase in both hs-CRP and apelin post-procedure(P=0.006 and P<0.0001,respectively).Patients with reduced left ventricular ejection fraction(LVEF) had significantly lower baseline apelin levels compared to those with normal ventricular function [(46.8±10.8) vs.(72.0±8.4) pg/ml,P<0.001].However,apelin increased to a level similar to the level of those with normal left ventricular systolic function 24 h after the PCI procedure [(86.7±11.6) vs.(85.1±6.1) pg/ml,P=0.72].Conclusions:hs-CRP and apelin levels increased after PCI and sirolimus-eluting stent *** with impaired left ventricular systolic function had significantly lower baseline apelin levels,which increased significantly after PCI.

关键词： High sensitive C-reactive protein (hs-CRP) Apelin Percutaneous colonary intervention (PCl)

基于3S技术的流域非点源污染定量模型及其研究展望

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水土保持学报 2002年第6期16卷 39-42,49页

作者：王伟武朱利中王人潮浙江大学环境科学系浙江杭州310028 浙江大学农业遥感与信息技术应用研究所浙江杭州310029

论述了流域非点源污染定量模型的类型,3S技术在流域非点源污染定量模型研究的应用及其局限性,明确了今后基于3S技术的流域非点源污染定量模型的发展方向和研究领域,特别关注了近年来地统计技术、高光谱遥感技术、智能3S技术等对流域非... 详细信息

论述了流域非点源污染定量模型的类型,3S技术在流域非点源污染定量模型研究的应用及其局限性,明确了今后基于3S技术的流域非点源污染定量模型的发展方向和研究领域,特别关注了近年来地统计技术、高光谱遥感技术、智能3S技术等对流域非点源污染定量模型研究带来的应用前景。

关键词：非点源污染定量模型地统计学高光谱遥感技术智能3S技术

The investigation of the stability of DNA-b-PPO vesicles formed through frame guided assembly

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Science china Chemistry 2018年第12期61卷 1568-1571页

作者： Bo Bian Yi-Yang Zhang Yuan-Chen Dong Fen wu chao Wang Shuo Wang Yun Xu Dong-sheng Liu department of Chemistry Tsinghua University College of Chemistry and Materials Engineering Wenzhou University Center for Medical Device Evaluation China Food and Drug Administration (CFDA)

Frame-guided assembly is a novel assembly method which can control the shape and size of vesicles accurately. It has been reported that the DNA-b-PPO vesicles could be stable over two weeks. In this communication we have introduced restriction sites of EcoR1 in the interior DNA scaffold to the formed vesicles in order to further study their stability. Dynamic light scattering(DLS), transmission electron microscope(TEM) and fluorescence spectrum were used to characterize the digestion process. The final results revealed that the vesicles were still stable even after two weeks cultivated with EcoR1, which suggests potential in future biological applications.

关键词： frame-guided assembly vesicles stability restriction sites EcoR1

NaF assisted preparation and the improved corrosion resistance of high content ZnO doped plasma electrolytic oxidation coating on AZ31B alloy

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Journal of Magnesium and Alloys 2024年第9期12卷 3602-3615页

作者： chao Yang Jian Huang Suihan Cui Ricky Fu Liyuan sheng Daokui Xu Xiubo Tian Yufeng Zheng Paul K.Chu Zhongzhen wu School of Advanced Materials Peking University Shenzhen Graduate SchoolShenzhen 518055China department of Physics Department of Materials Science&Engineeringand Department of Biomedical EngineeringCity University of Hong KongTat Chee AvenueKowloonHong Kong 999077China Shenzhen Institute Peking UniversityShenzhen 518057China PKU-HKUST ShenZhen-HongKong Institution Shenzhen 518057China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

In the present research,the NaF assisted plasma electrolytic oxidation(PEO)is designed to fabricate the high-content ZnO nanoparti-cles doped coating on AZ31B *** microstructure,phase constituents and corrosion behavior of the PEO coatings are investigated *** results reveal that the introduction of NaF promotes the formation of MgF2 nanophases in the passivation layer on Mg alloy,decreasing the breakdown voltage and discharge *** a result,the continuous arcing caused by high discharge voltage is *** the increasing of NaF content,the Zn content in the PEO coating is enhanced and the pore size in the coating is decreased *** to the high-content ZnO doping,the PEO coating protected AZ31B alloy demonstrates the better corrosion *** with the bare AZ31B alloy,the high-content ZnO doped PEO coated sample shows an increased corrosion potential from-1.465 V to-1.008 V,a decreased corrosion current density from 3.043×10^(-5) A·cm^(-2) to 3.960×10^(-8) A·cm^(-2) and an increased charge transfer resistance from 1.213×10^(2) ohm·cm^(2) to 2.598×10^(5) ohm·cm^(2).Besides,the high-content ZnO doped PEO coated sample also has the excellent corrosion resistance in salt solution,exhibiting no obvious corrosion after more than 2000 h neutral salt spraying and 28 days’immersion *** improved corrosion resistance can be ascribed to the relative uniform distribution of ZnO in PEO coating which can transform to Zn(OH)2 and form a continuous protective layer along the corrosion interface.

关键词： AZ31B alloy Plasma electrolytic oxidation(PEO) ZnO doping NaF Corrosion resistant

Endobiliary brush cytology during percutaneous transhepatic cholangiodrainage in patients with obstructive jaundice

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Hepatobiliary & Pancreatic Diseases International 2005年第1期4卷 98-103页

作者： Gu-sheng Xing Jin-chao Geng Xin-Wei Han Jin-Han Dai chao-Yang wu department of Radiology First Hospital of Tsinghua University Beijing 100016 China. xgs1259@***

BACKGROUND: Nonsurgical pathologic diagnosis of malignant bile duct stricture with a high sensitivity and specificity is desirable for therapeutic scheme. Percutaneous transhepatic endobiliary brush cytology in detecting obstructive jaundice is evaluated.METHODS: Fifty-eight consecutive patients with obstructive jaundice underwent percutaneous transhepatic cholangiodrainage (PTCD). During the process, a brush was inserted into the bile duct through the preexisted percutaneous transhepatic 8-F sheath, then exfoliated cells were collected from the bile duct stenosis and sent for cytologic diagnosis. The suspicious results were considered of negative diagnosis. All patients had relevant clinical data and follow-up results (15 months to 3 years). Statistical analysis was performed with the chi-square test and Fisher's exact test of probabilities, and a P value0.05).CONCLUSION: The results of this study indicate that cytological brushing of biliary stricture during PTCD is a useful method to establish a diagnosis of malignant biliary stenosis with a high sensitivity, but the negative predictive value is not satisfied.

关键词： bile duct neoplasm brush cytology diagnosis pathology

Optimization of the in vitro biodegradability,cytocompatibility,and wear resistance of the AZ31B alloy by micro-arc oxidation coatings doped with zinc phosphate

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Journal of Materials Science & Technology 2024年第12期179卷 224-239页

作者： chao Yang Suihan Cui Ricky KYFu Liyuan sheng Min Wen Daokui Xu Ying Zhao Yufeng Zheng Paul KChu Zhongzhen wu School of Advanced Materials Peking University Shenzhen Graduate SchoolShenzhen 518055China department of Physics Department of Materials Science&Engineeringand Department of Biomedical EngineeringCity University of Hong KongTat Chee AvenueKowloonHong Kong 999077China Shenzhen Institute Peking UniversityShenzhen 518057China PKU-HKUST Shenzhen–Hong Kong Institution Shenzhen 518057China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518055China National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composite Shanghai Jiao Tong UniversityShanghai 200240China

As implanted bone fixation materials,magnesium(Mg)alloys have significant advantages because the density and elastic modulus are closest to those of the human bone and they can bio-degrade in the physiological ***,Mg alloys degrade too rapidly and uncontrollably thus hampering clinical *** this study,a highly corrosion-resistant zinc-phosphate-doped micro-arc oxidation(MAO)coating is prepared on the AZ31B alloy,and the degradation process is assessed in *** increasing zinc phosphate concentrations,both the corrosion potentials and charge transfer resistance of the AZ31B alloy coated with MAO coatings increase gradually,while the corrosion current densities di-minish *** tests in the simulated body fluid(SBF)reveal that the increased zinc phos-phate concentration in MAO coating decreases the degradation rate,consequently reducing the release rates of Mg^(2+)and OH-in the physiological micro-environment,which obtains the lowest weight loss of only 5.22%after immersion for 56 *** regulation of degradation provides a weak alkaline environment that is suitable for long-term cell growth and subsequent promotion of bone proliferation,differentiation,mineralization,and *** addition,the zinc-phosphate-doped MAO coat-ings show an improved wear resistance as manifested by a wear rate of only 3.81 x 10^(-5) mm^(3) N^(-1) m^(-1).The results reveal a suitable strategy to improve the properties of biodegradable Mg alloys to balance tissue healing with mechanical degradation.

关键词： Mg alloys MAO coatings Degradation regulation Cytocompatibility Wear resistance

Selective 1,4-arylsulfonation of 1,3-enynes via photoredox/nickel dual catalysis

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Organic Chemistry Frontiers 2022年第3期9卷 788-794页

作者： chao Li Duo-Duo Hu Ruo-Xing Jin Bing-Bing wu Cheng-Yu Wang Zhuofeng Ke Xi-sheng Wang School of Materials Science&Engineering School of ChemistryPCFM LabSun Yat-Sen UniversityGuangzhou 510275P.R.China Hefei National Laboratory for Physical Sciences at the Microscale and department of Chemistry Center for Excellence in Molecular Synthesis of CASUniversity of Science and Technology of China96 Jinzhai RoadHefeiAnhui 230026China

A photoredox/nickel-catalyzed selective 1,4-arylsulfonation of 1,3-enynes to access structurally diverse sulfone-containing allenes has been *** radical cascade transformation featured easy manipulation,mild conditions,low catalyst loading,broad substrate scope,and large-scale *** preliminary mechanistic studies indicated a possible radical-relay process enabled by the radical capture of nickel(0)species.

关键词： synthesis nickel redox

Estimation and test of restricted linear EV model with nonignorable missing covariates

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Applied mathematics(A Journal of Chinese Universities) 2018年第3期33卷 344-358页

作者： TANG Lin-jun ZHENG sheng-chao ZHOU Zhan-gong department of Statistics Jiaxing University

This paper deals with estimation and test procedures for restricted linear errors-invariables(EV) models with nonignorable missing covariates. We develop a restricted weighted corrected least squares(WCLS) estimator based on the propensity score, which is fitted by an exponentially tilted likelihood method. The limiting distributions of the proposed estimators are discussed when tilted parameter is known or unknown. To test the validity of the constraints,we construct two test procedures based on corrected residual sum of squares and empirical likelihood method and derive their asymptotic properties. Numerical studies are conducted to examine the finite sample performance of our proposed methods.

关键词： errors-in-variables model nonignorable missing data propensity score smoothed empirical likelihood