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Effects of Oxygen on the Microstructure of Ti_(47)Al_(0.7)B Alloys

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Journal of Materials Science & Technology 2010年第2期26卷 131-135页

作者： Yingche Ma Zhiguo Jiang Bo Chen Xiujuan Zhao ming gao Kui liu Yiyi Li Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The effects of oxygen on the microstructure of Ti-47Al-0.7B （at. pct） alloy for as-cast automotive valves were investigated. Six alloys with oxygen content from 0.4 to 1.4 at. pct were prepared by induction melting and centrifugal casting in CaO crucible under protective atmosphere. The microstructures were observed by optical microscopy （OM） and scanning electron microscope （SEM）. The results show that the increase of oxygen content led to grain refinement and enhanced the microhardness as well as the α2 volume fraction in the TiAl-based alloys.

关键词： Microstructure Oxygen content Grain refinement TiAl-based alloys

Changes of Oxygen Content in Molten TiAl Alloys as a Function of Superheat during Vacuum Induction Melting

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Journal of Materials Science & Technology 2010年第10期26卷 900-903页

作者： Bo Chen,Yingche Ma,ming gao and Kui liu Institute of Metal Research,Chinese Academy of sciences,Shenyang 110016,China Institute of Metal Research Chinese Academy of sciences

Experimental studies on the melting process of titanium aluminum alloy have been pursued from the viewpoint of *** alloys were prepared with vacuum induction melting （VIM） in calcia crucibles at 1873 K and 1923 K in order to determine the behavior of the oxygen content as a function of temperature,time and frequency of *** experiment results showed that alloys were uncontaminated except for the increasing of oxygen content which was introduced from the reaction CaO（s）=Ca（in TiAl）＋O（in TiAl）,and the standard Gibbs energy of the reaction was determined to be △G0 =274000 102.8T（J/mol）.Oxygen content increased slowly with the melting time by about 50×10-6 wt pct/min,and decreased with induction melting *** superheat and higher melting frequency can be used to reduce oxygen content increasing rate.

关键词： TiAl alloys Induction melting Calcia crucible Oxygen content

Effect of austenitizing condition on mechanical properties,microstructure and precipitation behavior of AISI H13 steel

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Journal of Iron and Steel Research International 2024年第1期31卷 143-156页

作者： An-gang Ning Yang liu Rui gao Stephen Yue ming-bo Wang Han-jie Guo College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Department of Mining and Materials Engineering McGill UniversityMontrealQCH3A 0C5Canada ASSAB Tooling Technology(Chongqing)Co. Ltd.Chongqing401120China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

The effects of austenitizing temperature(1223,1303,and 1373 K)and holding time(1-1500 s)on the microstructure,mechanical properties,and precipitation behavior of the H13 hot work die steel were *** results indicate a softening phenomenon when H13 steel is austenitized at 1303 K beyond 900 s and 1373 K beyond 600 s,*** the sample held for 1200 s,the tensile strength is found capable of reaching up to 2.2 GPa when quenched from a temperature above 1303 ***,prior-austenite grain size increases with the increase in austenitizing *** kinetic behavior of the precipitates(mainly MC-type carbides)in H13 steel could be elaborated through the principles set forth by the Arrhenius and Avrami ***,the comprehensive strengthening of the H13 steel was discussed in *** results show that the activation energy of the transformed fraction of carbides is higher than that of the diffusion process for common alloying elements(Cr,V,Mo,and Ni)found in the *** suggests that it would be difficult for precipitates to dissolve into the matrix when H13 steel is austenitized at high *** the increasing austenitizing temperature,the precipitation fraction decreases,and the dislocation density *** dislocation strengthening is regarded as the dominant strengthening contributed to yield strength in as-quenched H13 steel.

关键词： H13 steel Austenitizing Mechanical property Precipitation behavior Comprehensive strengthening

Inhibition of viability of human retinal microvascular endothelial cells by vialinin A under high glucose condition

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International Journal of Ophthalmology(English edition) 2024年第10期17卷 1809-1815页

作者： Zhi-Gang Chen gao-Qin liu Wei-ming liu Pei-Rong Lu Department of Ophthalmology the First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina Jiangsu Clinical Immunology Institute the First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina

AIM:To investigate the effects of vialinin A on viability of human retinal endothelial cells(HRECs)under high glucose condition and its potential ***:The HRECs were divided into four groups:normal glucose control group(NG,5 mmol/L D-glucose),high glucose group(HG,30 mmol/L D-glucose),HG+1μmol/L vialinin A group,and HG+5μmol/L vialinin A *** cell viabilities were measured with cell counting kit-8(CCK-8)assay for proliferation,with scratch assay for migration,and tube formation,for evaluation of the impact of vialinin A on cellular ***-time PCR and Western blotting were used to determine the expression level of vascular endothelial growth factor(VEGF).RESULTS:The proliferative capacity and migration of HRECs was reduced by 5μmol/L vialinin A in high glucose environment(both P<0.05).Vialinin A also inhibited highglucose-induced tube formation of *** expression level of VEGF and PI3K in HRECs was also significantly decreased by vialinin A(P<0.05).CONCLUSION:Vialinin A inhibits the cell viability of *** may serve as a potential target for anti-angiogenic therapy.

关键词： vialinin A vascular endothelial growth factor human retinal endothelial cells cell viability

Robotic versus laparoscopic surgery for sporadic benign insulinoma:Short-and long-term outcomes

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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 399-405页

作者： Zhu-Zeng Yin Yuan-Xing gao Zhi-ming Zhao ming-Gen Hu Wen-Bo Tang Rong liu Faculty of Hepato-Pancreato-Biliary Surgery The First Medical CenterChinese PLA General HospitalBeijing 100853China Institute of Hepatobiliary Surgery of Chinese PLA Beijing 100853China Key Laboratory of Digital Hepatobiliary Surgery of Chinese PLA Beijing 100853China

Background:Minimally invasive surgery is the optimal treatment for *** present study aimed to compare short-and long-term outcomes of laparoscopic and robotic surgery for sporadic benign ***:A retrospective analysis of patients who underwent laparoscopic or robotic surgery for insulinoma at our center between September 2007 and December 2019 was *** demographic,perioperative and postoperative follow-up results were compared between the laparoscopic and robotic ***:A total of 85 patients were enrolled,including 36 with laparoscopic approach and 49 with robotic *** was the preferred surgical ***-nine patients(69.4%)underwent enucleation;among them,26 and 33 patients underwent laparoscopic and robotic surgery,*** enucleation had a lower conversion rate to laparotomy(0 vs.19.2%,P=0.013),shorter operative time(102.0 vs.145.5 min,P=0.008)and shorter postoperative hospital stay(6.0 vs.8.5 d,P=0.002)than laparoscopic *** were no differences between the groups in terms of intraoperative blood loss,the rates of postoperative pancreatic fistula and *** a median follow-up of 65 months,two patients in the laparoscopic group developed a functional recurrence and none of the patients in the robotic group had a ***:Robotic enucleation can reduce the conversion rate to laparotomy and shorten operative time,which might lead to a reduction in postoperative hospital stay.

关键词： Robotic surgical procedures Laparoscopy Insulinoma Enucleation Pancreatectomy

Improved mammalian family phylogeny using gap-rare multiple sequence alignment:A timetree of extant placentals and marsupials

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Zoological Research 2023年第6期44卷 1064-1079页

作者： gao-ming liu Qi Pan Juan Du Ping-Fen Zhu Wei-Qiang liu Zi-Hao Li Ling Wang Chun-Yan Hu Yi-Chen Dai Xiao-Xiao Zhang Zhan Zhang Yang Yu Meng Li Peng-Cheng Wang Xiao Wang ming Li Xu-ming Zhou Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China School of Life Sciences University of Science and Technology of ChinaHefeiAnhui 230026China College of Life Sciences Nanjing Normal UniversityNanjingJiangsu 210023China

The timing of mammalian diversification in relation to the Cretaceous-Paleogene(KPg)mass extinction continues to be a subject of substantial *** studies have either focused on limited taxonomic samples with available whole-genome data or relied on short sequence alignments coupled with extensive species *** the present study,we improved an existing dataset from the landmark study of Meredith et al.(2011)by filling in missing fragments and further generated another dataset containing 120 taxa and 98 exonic *** these two datasets,we then constructed phylogenies for extant mammalian families,providing improved resolution of many conflicting ***,the timetrees generated,which were calibrated using appropriate molecular clock models and multiple fossil records,indicated that the interordinal diversification of placental mammals initiated before the Late Cretaceous ***,intraordinal diversification of both extant placental and marsupial lineages accelerated after the KPg boundary,supporting the hypothesis that the availability of numerous vacant ecological niches subsequent to the mass extinction event facilitated rapid ***,our results support a scenario of placental radiation characterized by both basal cladogenesis and active interordinal divergences spanning from the Late Cretaceous into the Paleogene.

关键词： Mammals Phylogeny Diversification Evolutionary model

An Improved Thermal Conductivity Measurement Scheme for Macroscopic Graphitic Films Using the Laser Flash Method

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Journal of Thermal Science 2024年第4期33卷 1480-1490页

作者： ZHANG Peijuan ming Xin liu Yingjun WANG Xuelong SHI Hang HAO Yuanyuan LU Jiahao liu Zheng LAI Haiwen ZHANG Ying gao Weiwei XU Zhen gao Chao MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringKey Laboratory of Adsorption and Separation Materials&Technologies of Zhejiang ProvinceZhejiang UniversityHangzhou310027China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan030032China Special Equipment Safety Supervision and Inspection Institute of Jiangsu Province National Graphene Products Quality Inspection and Testing Center(Jiangsu)Wuxi214174China Hangzhou gaoxi Technol Co. LtdHangzhou311113China China Academy of Aerospace Aerodynamics Beijing100074China

Achieving efficient thermal management urges to exploit high-thermal-conductivity materials to satisfy the boosted demand of heat *** is critical to adopt standardized characterization protocols to evaluate the intrinsic thermal conductivity of thermal management ***,for the most representative laser flash method,the lack of standard measurement methodology and systematic description on the thermal diffusivity and influencing factors has led to significant deviations and confusion of the thermal conduction performance in the emerging thermal management ***,the measurement error factors of thermal diffusivity by the common laser flash analyzer(LFA)are *** high-thermal-conductivity graphitic film(GF)as a typical case,the key factors are analyzed to guide the measurement protocol of related carbon-based thermal management *** basic principle of the LFA measurement,actual pre-processing conditions,instrument parameters setting,and data analysis are elaborated for accurate ***,the graphene thick films and common isotropic materials are also extended to meet various thermal measurement *** on the existing practical problems,we propose a feasible test flow to achieve a unified and standardized thermal conductivity measurement,which is beneficial to the rapid development of carbon-based thermal management materials.

关键词： thermal management graphitic film laser flash method thermal conductivity thermal diffusivity

Phase-engineering modulation of Mn-based oxide cathode for constructing super-stable sodium storage

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Journal of Energy Chemistry 2024年第1期88卷 421-427,I0010页

作者： Quanqing Zhao Ruru Wang ming gao Bolin liu Jianfeng Jia Haishun Wu Youqi Zhu Chuanbao Cao Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education School of Chemistry and Materials ScienceShanxi Normal UniversityTaiyuan 030032ShanxiChina Metals and Chemistry Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China Research Center of Materials Science Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green ApplicationsBeijing Institute of TechnologyBeijing 100081China

The Mn-based oxide cathode with enriched crystal phase structure and component diversity can provide the excellent chemistry structure for Na-ion ***,the broad application prospect is obstructed by the sluggish Na^(+)kinetics and the phase transitions upon ***,we establish the thermodynamically stable phase diagram of various Mn-based oxide composites precisely controlled by sodium content tailoring strategy coupling with co-doping and solid-state *** chemical environment of the P2/P'3 and P2/P3 biphasic composites indicate that the charge compensation mechanism stems from the cooperative contribution of anions and *** from the no phase transition to scavenge the structure strain,P2/P'3 electrode can deliver long cycling stability(capacity retention of 73.8%after 1000 cycles at 10 C)and outstanding rate properties(the discharge capacity of 84.08 mA h g^(-1)at 20 C)than P2/P3 ***,the DFT calculation demonstrates that the introducing novel P'3 phase can significantly regulate the Na^(+)reaction dynamics and modify the local electron configuration of *** effective phase engineering can provide a reference for designing other high-performance electrode materials for Na-ion batteries.

关键词： Sodium ion battery Oxide cathode Phase engineering Phase diagram Na~+kinetic

Critical approaches in the catalytic transformation of sugar isomerization and epimerization after Fischer-History,challenges,and prospects

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Green Energy & Environment 2024年第3期9卷 435-453页

作者： Da-ming gao Xun Zhang Haichao liu Hidemi Fujino Tingzhou Lei Fuan Sun Jie Zhu Taoli Huhe National-local Joint Engineering Research Center of Biomass Refine and High-Quality Utilization Changzhou UniversityChangzhou213164China Institute of Urban and Rural Mining Research Changzhou UniversityChangzhou213164China Changzhou Key Laboratory of Biomass Green Safe&High Value UtilizationChangzhou UniversityChangzhou213164China Beijing National Laboratory for Molecular Science College of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China Department of Rehabilitation Science Kobe University Graduate School of Health SciencesKobe654-0142Japan

The transformation of aldose to ketose or common sugars into rare saccharides,including rare ketoses and aldoses,is of great value and interest to the food industry and for saccharidic biomass utilization,medicine,and the synthesis of ***,high-fructose corn syrup(HFCS)is industrially produced in more than 10 million tons annually using immobilized glucose *** low-calorie saccharides such as tagatose and psicose,which are becoming popular sweeteners,have also been produced on a pilot scale in order to replace sucrose and ***,current catalysts and catalytic processes are still difficult to utilize in biomass conversion and also have strong substrate dependence in producing high-value,rare *** the specific reaction properties of saccharides and catalysts,since the pioneering discovery by Fischer,various catalysts and catalytic systems have been discovered or developed in attempts to extend the reaction pathways,improve the reaction efficiency,and to potentially produce commercial *** this review,we trace the history of sugar isomerization/epimerization reactions and summarize the important breakthroughs for each reaction as well as the difficulties that remain unresolved to date.

关键词： Rare sugars Isomerization Ketonization Epimerization Catalytic transformation