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Rare Metals 2024年第5期43卷 2275-2281页

作者： guo-chao li Xu Cheng Hua-Ming Wang National Engineering Laboratory of Additive Manufacturing for Large Metallic Components and Engineering Research Center of Ministry of Education on Laser Direct Manufacturing for Large Metallic Components School of Materials Science and EngineeringBeihang UniversityBeijing 100191China

The solid solution and aging treatment for conventional manufacturing processes might not be suitable for laser additive manufactured titanium alloys due to the different lamellar *** this study,the influence of aging temperatures(600,700 and 800°C)on microstructure and mechanical properties of titanium alloy Ti-6Al-2V-1.5Mo-0.5Zr-0.3Si was *** results indicate that after solid solution treatment at 970°C followed by water quenching,the alloy mainly consists of coarsening lamellar a phase in martensite α' *** at 600°C will not change the size of primary lamellar α phase but lead to huge amount of secondary a phases(α_(s))generating with very fine *** increasing the aging temperature,the number of α_(s) decreases but with coarsened *** aged at 800°C,the width of the asphase reaches 350 nm,almost 7 times wider than that aged at 600°*** changing size of α_(s) obviously influences the property of the *** fine α_(s) leads to high strength and microhardness but low plasticity,and specimen aged at 700°C with suitable assize has the best comprehensive properties.

关键词： α+βtitanium alloy Laser additive manufacturing Solid solution and aging treatment Microstructure Room temperature tensile property

Effects of annealing temperature and cooling rate on microstructures of a novel titanium alloy Ti-6Al-2V-1.5Mo-0.5Zr-0.3Si manufactured by laser additive manufacturing

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Journal of Iron and Steel Research International 2018年第4期25卷 442-452页

作者： guo-chao li Xu Cheng Xiang-jun Tian National Engineering Laboratory of Additive Manufacturing for Large Metallic Components and Engineering Research Center of Ministry of Education on Laser Direct Manufacturing for Large Metallic Components School of Materials Science and Engineering Beihang University Beijing 100091 China

The microstructure changes of Ti-6Al-2V-1.5Mo-0.5Zr-0.3Si alloy manufactured by laser additive manufacturing （LAM） are systematically investigated with statistical analysis of primary α phase （αp） and secondary α phase （αs） under different annealing conditions. Results indicate that, with the increase in holding temperature, the content of αp lamellas decreases with the increasing αs content, maintaining the total α phases concentration stabilized. The width of αp lamellas and the nominal specific surface area of α phase both exhibit positive correlation with the temperature, while the increment of αp and the widths of αs lamellas show an increase-decrease tendency. Besides, with the decrease in cooling rate, the total content of α and the width of αp lamellas increase, while the nominal specific surface area of α phase shows no significant change. The results indicate that, in the annealing process, the holding temperature determines the surplus and growth interfaces of % lamellas, and the cooling rate influences the nucleation quantity of c^s in unit time. During the cooling stage, the αp lamellas grow initially, and then, the nucleation and crab-like structure growth occur followed by those of the αs lamellas. The time intervals among them are influenced by cooling rate. The mechanism of microstructure formation of the LAMed titanium alloy during annealing stage was discussed, which would guide for the heat treatment method to achieve required microstructure.

关键词： Novel titanium alloy Annealing Microstructure statistics Holding temperature Cooling rate

Improvement of proof-ultimate strength difference in laser additive manufactured Ti-6Al-2V-1.5Mo-0.5Zr-0.3Si alloy by tuning basketweave structure

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Journal of Iron and Steel Research International 2019年第6期26卷 631-636页

作者： guo-chao li Xu Cheng Hua-ming Wang National Engineering Laboratory of Additive Manufacturing for Large Metallic Components and Engineering Research Center of Ministry of Education on Laser Direct Manufacturing for Large Metallic Components School of Materials Science and Engineering Beihang University Beijing 100191 China Beijing Yuding Additive Manufacturing Research Institute Co. Ltd. Beijing 102206 China

After annealed at 1000 ℃, a special basket-weave structure is obtained in laser additive manufactured Ti-6Al-2V-1.5Mo- 0.5Zr-0.3Si alloy. The unit of the special basket-weave structure is a lamellas clusters, which consist of lamellar primary ot (otp), crab-like structures at the edges of otp and lamellar secondary a (as) on both sides of otp. As the units of basket-weave structures, the width of the clusters is much larger than that of a lamellas in as-deposited alloy. The formation temperature and process of the special basket-weave structure are studied, and the room temperature properties are tested and compared with the as-deposited alloy. The results show that the formation of the special basket-weave structure finishes within about 30 s and crab-like structures form earlier than lamellar as. The yield strength of the alloy is decreased by about 75 MPa compared to that of the as-deposited alloy. Besides, the proof-ultimate strength difference of the alloy is two times higher than that of the as-deposited alloy with about 34% improvement for the impact toughness. It is because ot colony size shows a positive correlation to the width of the unit forming basket-weave structure. The enhancement in proof-ultimate strengthdifference could significantly improve the toughness of the alloy, and thus effectively increase the safety of the alloy.

关键词： Titanium alloy Basket-weave structure Formation process a colony size Yield strength

Microstructure and properties of hybrid additive manufacturing 316L component by directed energy deposition and laser remelting

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Journal of Iron and Steel Research International 2020年第7期27卷 842-848页

作者： Xiao-hui Chen Bo Chen Xu Cheng guo-chao li Zheng Huang National Engineering Laboratory of Additive Manufacturing for Large Metallic Components and Engineering Research CenterMinistry of Education on Laser Direct Manufacturing for Large Metallic ComponentsSchool of Materials Science and EngineeringBeihang UniversityBeijing 100191China Research Center for Processing AECC Shanghai Commercial Aircraft Engine Manufacturing Co.Ltd.Shanghai 201306China

Arc additive manufacturing is a high-productivity and low-cost technology for directly fabricating fully dense metallic ***,this technology with high deposit rate would cause degradation of dimensional accuracy and surface quality of the metallic component.A novel hybrid additive manufacturing technology by combining the benefit of directed energy deposition and laser remelting is *** hybrid technology is successfully utilized to fabricate 316L component with excellent surface *** show that laser remelting can largely increase the amount ofδphases and eliminateσphases in additive manufacturing 316L component surface due to the rapid *** leads to the formation of remelting layer with higher microhardness and excellent corrosion resistance when compared to the steel made by directed energy deposition *** laser remelting power can improve surface quality as well as corrosion resistance,but degrade microhardness of remelting layer owing to the decrease inδphases.

关键词： Hybrid additive manufacturing Laser remelting Directed energy deposition Microstructure Corrosion resistance

A simple and efficient synthesis of 2-substituted benzothiazoles catalyzed by H_2O_2/HCl

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Chinese Chemical Letters 2009年第12期20卷 1408-1410页

作者： Hong Yun guo Ji chao li You Le Shang College of Chemical Engineering and Materials Science Zhejiang University of Technology Hangzhou 310014 China

A simple and efficient procedure for the synthesis of substituted benzothiazoles through condensation of 2-aminothiophenol with aromatic aldehydes in the presence of H2O2/HCl system in ethanol at room temperature is described. The target compounds have been characterized by ^1H NMR, ^13C NMR, IR and MS. Short reaction time, easy and quick isolation of the products, and excellent yields are the main advantages of this procedure.

关键词： 2-Substituted benzothiazoles Heterocyclic compounds H2O2/HCl

Distributed Field Rotator Composed of Isolated Components

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Chinese Physics Letters 2014年第4期31卷 50-53页

作者： liU guo-Chang li chao SHAO Jin-Jin FANG Guang-You Key Laboratory of Electromagnetic Radiation and Sensing Technology Chinese Academy of Sciences Beijing 100190

Transformation optics offers remarkable control over electromagnetic fields and has recently opened an exciting gateway to design ＇field rotator devices＇. We propose a distributed field rotator with open windows based on composite transformation optics, which consists of a central circular region and several isolated components. The number, position and size of the components can be controlled freely by the design purpose. Full-wave simulations are performed to demonstrate its function, which is equivalent to a classic field rotator. However, such a distributed rotator makes it much easier to access and make use of the rotated field in the central region, compared to the closed classic field rotator, especially in the case of 3D situations.

关键词： Components Distributed components

Heme oxygenase-1 induction by hemin protects liver cells from ischemia/reperfusion injury in cirrhotic rats

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World Journal of Gastroenterology 2007年第40期13卷 5384-5390页

作者： Hui Xue Hua guo Ying-chao li Zhi-Ming Hao Department of Gastroenterology The First Affiliated Hospital Xi'an Jiaotong University Medical College Xi'an 710061 Shaanxi Province China

AIM： To investigate the potential protective effect of HO-1 on cirrhotic liver cells in rats.METHODS： Male Wistar rats included in the current study were randomly divided into 5 groups as follows： normal （N） group; liver cirrhotic （LC） group; sham （S） group; I/R group and I/R ＋ hemin group. The model for inducing liver cirrhosis in rats was established according to a previously published protocol. Following this the segmental hepatic ischemia reperfusion operation was carried out. The rats were treated with 30 l^mol/kg hemin （HO-1 inducer, ferric portoporphyrin IX chloride） i.p. or 0.9% NaCI （control） 24 h and 12 h before hepatic ischemia for 30 min or sham laparotomy. Blood was collected for serum enzymatic measurement 6 and 12 h after reperfusion or sham laparotomy. HO-1, NF-κB and caspase-3 expressions were assessed by immunohistochemical analysis.RESULTS： The expressions of proteins are inversely correlated to the gray values. HO-1 expression in the I/R ＋ hemin group was increased significantly than I/R group at 6 h and 12 h after hepatic I/R （6 h： 112.0± 8.3 vs 125.1± 5.7, P 〈 0.01; 12 h： 120.8± 11.0 vs 132.4 ± 6.2, P 〈 0.01）. Hemin improved serum manganese superoxide dismutase （MnSOD）（6 h： 131.3 ± 17.6 vs 107.0 ± 13.9, P 〈 0.01; 12 h： 141.4 ：E 12.5 vs 118.3± 10.2, P 〈 0.01）, lessened liver cell injury, decreased caspase-3（6 h： 166.7 ± 8.1 vs 145.5 ± 14.6, P 〈 0.01; 12 h： 172.8± 3.8 vs 148.0 ±6.5, P 〈 0.01） and NF-κB expression （6 h： 150.2 ± 8.6 vs 139.7 ±6.0, P 〈 0.01; 12 h： 151.1 ± 5.9 vs 148.1± 5.3, P 〉 0.05） and serum alanine aminotransferase （ALT）（6 h： 413.3± 104.1 vs 626.8 ±208.2, P 〈 0.01; 12 h： 322.2 ± 98.8 vs 425.8 ± 115.4, P 〈 0.05）, aspartate aminotransferase （AST）（6 h： 665.2 ± 70.1 vs 864.3± 70.4, P 〈 0.01; 12 h： 531.1 ± 98.6 vs 664.4± 115.6, P 〈 0.01）, malondialdehyde （MDA） levels （6 h： 11.1 ± 2.17 vs 13.5 ±2.01, P 〈 0.01; 12 h： 9.36 ±1.10 vs 10.8 ± 1.62, P 〈 0.05） in the I/R ＋ hemin group when compared with the I/R group.CONCLUSION： These

关键词： Heme oxygenase-1 Ischemia reperfusion Caspase-3 Nuclear factor-κB liver cirrhosis

Effects of residual plastic film on crop yield and soil fertility in a dryland farming system

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Journal of Integrative Agriculture 2023年第12期22卷 3783-3791页

作者： WANG Dong XI Yue SHI Xiao-yan guo chao-li ZHONG Yu-jie SONG chao GUAN Yu HUANG Lu YANG Qi-feng li Feng-min College of Ecology Taiyuan University of TechnologyTaiyuan 030024P.R.China College of Agriculture Nanjing Agricultural UniversityNanjing 210095P.R.China State Key Laboratory of Grassland Agro-Ecosystems Institute of Arid Agroecology/College of EcologyLanzhou UniversityLanzhou 730000P.R.China Teaching Affairs Office Jilin Normal UniversitySiping 136099P.R.China Department of Resources and Environmental Science College of Agriculture/The Key Laboratory of Oasis Eco-Agriculture of the Xinjiang Production and Construction CorpsShihezi UniversityShihezi 832000P.R.China Institute of Microbiology Chinese Academy of SciencesBeijing 100101P.R.China Gansu Provincial Department of Agriculture and Rural Affairs Lanzhou 730000P.R.China

Plastic film mulch in agricultural production becomes essential to maintaining crop yields in arid and semiarid ***,the presence of residual film in farmland soil has also drawn much *** this study,three experiments were *** first two experimental designs included 0,450,1350,and 2700 kg ha^(-1) of residual film pieces of approximately 5 cm side length added to field soil(0-20 cm soil depth)for seven years and added to pots for four *** the third experiment,1350 kg ha^(-1)of the residual film with different side lengths(2-5,5-10,10-15,and 15-20 cm)was added to field soil for six years to explore the effect of residual film fragment size on soil nutrients,soil microorganisms,crop growth and *** residual film had little effect on the soil moisture at a field depth of 0-2(or 0-1.8)*** were no significant effects on organic carbon,total nitrogen,inorganic nitrogen,total phosphorus or available phosphorus in the 0-20 cm soil *** presence of residual film decreased the richness and diversity of the bacterial community of the surface soil of the residual film,but it had no significant effect on the microbial community of the non-surface *** emergence rates of wheat and lentils occasionally decreased significantly with different amounts of residue fragments added to the *** 450-2700 kg ha^(-1),the residual film reduced the plant height and stem diameter of maize and significantly reduced the shoot biomass of harvested maize by 11-19%.The average yields of maize and potato over the seven years decreased,but there were almost no significant statistical differences among the *** results provide important data for a comprehensive scientific understanding of the effects of residual film on soil and crops in dryland farming systems.

关键词： residual film soil nutrients microbial community crop yield

Freestanding MoSe_(2)nanoflowers for superior li/Na storage properties

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Tungsten 2024年第1期6卷 238-247页

作者： Qiao Cu chao-Qun Shang guo-Fu Zhou Xin Wang Guangdong Provincial Key Laboratory of Optical Information Materials South China Normal UniversityGuangzhou 510006China School of Materials Science and Engineering and Hubei Key Laboratory of Plasma Chemistry and Advanced Materials Wuhan Institute of TechnologyWuhan 430205China International Academy of Optoelectronics at Zhaoqing South China Normal UniversityZhaoqing 526060China

MoSe_(2),with high theoretical specific capacity,has attracted a lot of *** remains an open challenge to effectively suppress the irreversible selenium dissolution and rapid capacity decrease induced by severe volume change during ***,we synthesize MoSe_(2)nanoflowers dispersed on one-dimensional(1D)N-doped carbon nanofibers(MoSe_(2)@NCNFs)for use as a freestanding *** this unique structure,the 1D N-doped carbon nanofibers are found to not only enhance the conductivity but also ensure the structural integrity during the li^(+)/Na^(+)insertion/destraction *** expected,at 2 A·g^(-1),the specific capacity of the MoSe_(2)@NCNFs is maintained at 180 mAh·g^(-1)after 500 cycles when used in lithium storage ***,in the case of sodium storage,at 1 A·g^(-1),the MoSe_(2)@NCNFs shows a capacity of 122mAh·g^(-1)after 500 *** findings suggest that the MoSe_(2)@NCNF electrodes may be a promising candidate for use in reversible li/Na storage applications.

关键词： li/Na storage Freestanding electrode MoSe_(2) Electrochemical reaction kinetics Structural integrity

Side Information-Based Stealthy False Data Injection Attacks Against Multi-Sensor Remote Estimation

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1054-1056页

作者： Haibin guo Zhong-Hua Pang chao li the Key Laboratory of Fieldbus Technology and Automation of Beijing North China University of TechnologyBeijing 100144China

Dear Editor,This letter investigates a novel stealthy false data injection(FDI)attack scheme based on side information to deteriorate the multi-sensor estimation performance of cyber-physical systems(CPSs).Compared with most existing works depending on the full system knowledge,this attack scheme is only related to attackers'sensor and physical process *** design principle of the attack signal is derived to diverge the system estimation ***,it is proven that the proposed attack scheme can successfully bypass the residual-based ***,all theoretical results are verified by numerical simulation.

关键词： estimation scheme system