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Journal of Iron and Steel Research International 2024年第1期31卷 264-274页

作者： Neng-yong Ye Guang-liang zhang Tian-yue Huang ming Cheng Shi-hong zhang Lei Wang School of Materials Science&Engineering Taizhou UniversityTaizhou318000ZhejiangChina Institute of Metal Research Chinese Academy of SciencesShenyang110016LiaoningChina

Due to the important role ofδphase's quantity and morphology in the mechanical and fatigue properties of Inconel 718 alloy and its components,it is necessary to renew insights into the effect of cold deformation on theδphase precipitation,especially on the morphology ***,the nucleation and growth behavior ofδphase in cold-rolled Inconel 718 alloy during aging were *** results show that the precipitation rate and volume fraction ofδphase increase with increasing the cold rolling reduction from 10%to 50%.The volume fraction ofδphase reaches equilibrium after 5 h,remaining at 5.98%,6.52%,and 6.79%under different rolling reductions(10%,30%,and 50%),*** nucleation ofδphase mainly occurs on different sites(grain boundaries,new twin boundaries and old twin boundaries)under 10%rolling reduction,whileδphase mainly nucleates on the new grain boundaries of static recrystallization due to 50%rolling *** the growth ofδphase undergoes a process of alternate orientation growth from spherical(nucleation)→short rod(longitudinal orientation growth)→short rod(radial orientation growth)→dynamic *** 10%rolling reduction,δphase tends to grow into the matrix,while under 50%rolling reduction,the orientation grows faster and is easily affected by the grain boundary curvature.

关键词： Inconel 718 alloy Cold rolling δphase Orientation growth Morphology evolution

Continuous regional arterial infusion for the treatment of severe acute pancreatitis: a meta-analysis

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Hepatobiliary & Pancreatic Diseases International 2015年第1期14卷 10-17页

作者： Feng-Jiao Yong Xuan-yue Mao Li-Hui Deng ming-ming zhang Qing Xia Sichuan Provincial Pancreatitis Center Department of Integrated Traditional and Western Medicine West China Hospital Sichuan University Chinese Evidenced-Based Medical Center West China Hospital Sichuan University

BACKGROUND： Continuous regional arterial infusion（CRAI） is a drug delivery system, which dramatically increases the drug concentration in the pancreas. Previous clinical and basic studies have demonstrated the possible therapeutic efficacy of CRAI for severe acute pancreatitis（SAP）. This meta-analysis of all published randomized controlled trials（RCTs） was conducted to assess the efficacy and safety of CRAI for the treatment of SAP. DATA SOURCES： Up to August 10, 2014, RCTs comparing CRAI with intravenous infusion for SAP in PubM ed, Embase, EBSCO, MEDLINE, Science Citation Index Expanded, Cochrane Library, China Academic Journals Full-Text Database, Chinese Biomedical Literature Database, and Chinese Scientific Journals Database were selected by two independent reviewers. The relative risk（RR） and their 95% confidence intervals（CI） for duration of elevated serum amylase and urine amylase, duration of abdominal pain, infection rate, incidence of complication, overall mortality, curative rate, hospital stay and details of subgroup analysis were extracted. Meta-analyses were made using the software Review Manager（RevM an version 5.10）.RESULTS： Six RCTs with 390 patients meeting the inclusion criteria were included in the final analysis. Compared with intravenous infusion route, CRAI significantly shortened the duration of elevated urine amylase（MD=-2.40, 95% CI=-3.20,-1.60; P〈0.00001） and the duration of abdominal pain（MD=-1.46, 95% CI=-1.94,-0.98; P〈0.00001）, decreased the incidence of complication（RR=0.35, 95% CI=0.15, 0.81; P=0.01） and overall mortality（RR=0.25, 95% CI=0.08, 0.78;P=0.02）, shortened the duration of hospital stay（MD=-10.36, 95% CI=-17.05,-3.68; P=0.002）, and increased the curative rate（RR=1.66, 95% CI=1.13, 2.46; P=0.01）. No mortality and catheter-related infections due to CRAI administration was reported in these studies. Subgroup analysis showed that the combination of drug administration via CRAI did not significantly improve the ***

关键词： severe acute pancreatitis continuous regional arterial infusion meta-analysis

Significant role of nanoscale Bi-rich phase in optimizing thermoelectric performance of Mg3Sb2

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Chinese Physics B 2020年第3期29卷 405-410页

作者： Yang Wang Xin zhang Yan-Qin Liu Jiu-Xing zhang ming yue Key Laboratory of Advanced Functional Materials Ministry of EducationCollege of Materials Science and EngineeringBeijing University of TechnologyBeijing 100124China School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China

Mg3Sb1.5Bi0.5-based alloys have received much attention,and current reports on this system mainly focus on the modulation of ***,there lacks the explanation for the choice of Mg3Sb1.5Bi0.5 as *** in this work,the thermoelectric properties of Mg3Sb2-xBix(0.4≤x≤0.55)compounds are systematically investigated by using the first principles calculation combined with *** calculated results show that the band gap decreases after Bi has been substituted for Sb site,which makes the thermal activation *** maximum figure of merit(ZT)is 0.27 at 773 K,which is attributed to the ultra-low thermal conductivity 0.53 W·m-1·K-1 for x=*** large mass difference between Bi and Sb atoms,the lattice distortion induced by substituting Bi for Sb,and the nanoscale Bi-rich particles distributed on the matrix are responsible for the reduction of thermal *** introduction of Bi into Mg3Sb2-based materials plays a vital role in regulating the transport performance of thermoelectric materials.

关键词： first principles calculations nanoscale Bi-rich phase Mg3Sb2 thermoelectric performance

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祁连山区草原畜牧业的可持续发展问题与发展模式

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山地学报 2001年第6期19卷 516-521页

作者：周立华樊胜岳张明军程国栋中国科学院寒区旱区环境与工程研究所冻土工程国家重点实验室甘肃兰州730000

以祁连山区的肃南县为实验基地 ,通过对山区生态保护和经济发展之间现存问题的分析 ,提出了以草原管理、牲畜繁育和产业发展为主要内容的山区草原畜牧业发展模式。它突破了山区的地域限制 ,将山区与山下绿洲作为一个完整的生态—经济耦... 详细信息

以祁连山区的肃南县为实验基地 ,通过对山区生态保护和经济发展之间现存问题的分析 ,提出了以草原管理、牲畜繁育和产业发展为主要内容的山区草原畜牧业发展模式。它突破了山区的地域限制 ,将山区与山下绿洲作为一个完整的生态—经济耦合系统 ,使用跨学科的方法 ,将山区草原的生态保护与农户的经济增长兼容起来。

关键词：祁连山区草原畜牧业可持续发展模式萧南县生态经济耦合系统牲畜繁育

Atomistic Insights into the Tunable Transition from Cavitation to Crazing in Diamond Nanothread-Reinforced Polymer Composites

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Research 2020年第1期2020卷 1372-1383页

作者： Lu-Wen zhang Wei-ming Ji yue Hu Kim Meow Liew Department of Engineering Mechanics School of Naval ArchitectureOcean and Civil EngineeringShanghai 2002240Shanghai Jiao Tong UniversityChina Department of Architecture and Civil Engineering City University of Hong KongKowloonHong Kong SARChina

Cavitation and crazing in thermosetting polymers can be sophisticatedly designed for valuable applications in optics,electronics,and *** is a great challenge for numerical study to describe the formations of cavity and fibrils in polymer composite due to the complicated interfacial *** explore this challenging task,we exploit a two-phase coarse-grained framework which serves as an efficient atomistic level-consistent approach to expose and predict the transition between cavitation and crazing in a polymeric *** coarse-grained framework is utilized to transmit the information between single phase and interface in polymer composite,and the learning tasks of force field are fulfilled through parameterization of mechanical performances and structural *** elaborate on the intrinsic characteristics of the cavitation-crazing transition in diamond nanothread-(DNT-)reinforced polymethyl methacrylate composites,in which DNT plays a specific role of nanomodulator to tune the cavity volume *** transition from cavitation to crazing can be induced through a novel dissipative mechanism of opening an interlocked network,in which case the DNT is stretched to the aligned fibrils and links crazing tightly by interfacial *** designed computational framework can broaden the scope of theoretical tools for providing better insights into the microstructure design of polymer composites.

关键词： composite composites cavitation

Tool-path generation for industrial robotic surface-based application

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Advances in Manufacturing 2019年第1期7卷 64-72页

作者： He Lyu yue Liu Jiao-Yang Guo He-ming zhang Ze-Xiang Li Department of Electronic and Computer Engineering Hong Kong University of Science and Technology Hong Kong People's Republic of China Hong Kong University of Science and Technology Shenzhen Research Institute Shenzhen 518057 Guangdong People's Republic of China

Industrial robots are widely used in various applications such as machining, painting, and welding. There is a pressing need for a fast and straightforward robot programming method, especially for surface-based tasks. At present, these tasks are time-consuming and expensive, and it requires an experienced and skilled operator to program the robot for a specific task. Hence, it is essential to automate the tool-path generation in order to eliminate the manual planning. This challenging research has attracted great attention from both industry and academia. In this paper, a tool-path generation method based on a mesh model is introduced. The bounding box tree and kdtree are adopted in the algorithm to derive the tool path. In addition, the algorithm is integrated into an offline robot programming system offering a comprehensive solution for robot modeling, simulation, as well as tool-path generation. Finally, a milling experiment is performed by creating tool paths on the surface thereby demonstrating the effectiveness of the system.

关键词： Industrial robot Tool path generation Simulation Intelligent manufacturing

In-situ observation of magnetization reversal process of Sm(Co,Cu,Fe,Zr)_z magnets with different Fe contents

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Rare Metals 2020年第3期39卷 250-255页

作者： Shuo Wu Dong-Tao zhang ming yue Yun-Qiao Wang Zhi-Feng Shang Dan Wu Jing-ming Liang College of Materials Science and Engineering Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing100124China

Sm(Co,Cu,Fe,Zr)z magnets have drawn much attention for high-temperature applications due to their high Curie temperature,strong corrosion resistance and thermal *** effect of increasing Fe content on the distribution of elements and squareness(Sr)of demagnetization curves were investigated for two kinds of magnets with different nominal compositions of Sm(CobalFe0.15-Cu0.07Zr0.03)7.8 and Sm(CobalFe0.28Cu0.07Zr0.03)6.6 in this *** magnetic properties of the magnets with higher Fe content fluctuate greatly after different solution treatments,indicating that they are more sensitive to the process *** increase in Fe content can obviously enhance the cellular phase ***,inhomogeneous Cu distribution is observed in the Sm(CobalFe0.28-Cu0.07Zr0.03)6.6 magnet,resulting in the different cellular structures and corresponding magnetic domain patterns in different regions in the inner ***,the lower Cu content regions are responsible for the wider magnetic domain,which have weaker resistance to applied magnetic *** a result,Sr of demagnetization curve decreases with the increase in Fe content due to the inhomogeneous Cu distribution,which was confirmed by in-situ observation of electron probe micro-analyzer(EPMA)and magneto-optical Kerr optical microscope(MOKE).

关键词： Sm(Co,Cu,Fe,Zr)_z magnets Cu distribution Microstructure Magnetic properties Magnetic domain Squareness

Recycled Nd-Fe-B sintered magnets prepared from sludges by calcium reduction-diffusion process

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Journal of Rare Earths 2018年第12期36卷 1284-1291页

作者： Xiaowen Yin Min Liu Baicen Wan Yu zhang Weiqiang Liu Yufeng Wu Dongtao zhang ming yue College of Materials Science and Engineering Beijing University of Technology Institute of Circular Economy Beijing University of Technology

Environmental friendly recycling process for Nd-Fe-B sintered magnet sludges generated in the manufacturing process, which contain large amount of rare earth, including Nd, Pr and Dy, is badly needed so far. In present study, we have developed an effective route to obtain recycled sintered magnets from Nd-Fe-B sintered magnet sludges by calcium reduction-diffusion(RD) process. Compared to conventional recycling process, our research is focused on recovering most of the useful elements, including Nd, Pr, Dy, Co, and Fe together instead of just rare earth elements. To improve the recycling efficiency and reduce pollution, the co-precipitating parameters were simulated and calculated using MATLAB software. Most of useful elements were recovered by a co-precipitation method, and the obtained composite powders were then directly fabricated as recycled Nd-Fe-B powders by a calcium reduction-diffusion(RD) method. The recovery rates are 98%, 99%, 99%, 93%, and 99%, for Nd, Pr, Dy, Co, and Fe, respectively. The amount of useful elements contained in the recovered composite powders is greater than99.71 wt%. The process of RD for synthesizing NdFeB and subsequently removing CaO was thoroughly investigated. Furthermore, the recycled Nd-Fe-B magnet exhibits a remanence of 1.1 T, a coercivity of1053 kA/m, and an energy product of 235.6 kJ/m~3, respectively, indicating that recycled Nd-Fe-B sintered magnet was successfully recovered from the severely contaminated sludges via an effective recycling route.

关键词： Nd-Fe-B sintered magnet sludges Reduction-diffusion Removing CaO Recycled magnet Rare earths

Rich defects and nanograins boosted formaldehyde sensing performance of mesoporous polycrystalline ZnO nanosheets

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Rare Metals 2022年第7期41卷 2292-2304页

作者： Le-Xi zhang ming-Mei Zhao Yan-Yan Yin yue Xing Li-Jian Bie School of Materials Science and Engineering Tianjin Key Laboratory for Photoelectric Materials and DevicesKey Laboratory of Display Materials and Photoelectric Devices(Ministry of Education)National Demonstration Center for Experimental Function Materials EducationTianjin University of TechnologyTianjin 300384China Department of Environmental Science and Engineering Nankai University Binhai CollegeTianjin 300270China

Comprehensive consideration of structural and electronic sensitization is of significant importance for rational design and assembly of high-performance gas sensors based on metal *** this work,hierarchically mesoporous ZnO nanosheets are synthesized via a hydrothermal method followed by *** characterization reveals polycrystalline feature of these ZnO nanosheets rich in mesopores and *** sensing performance of as-synthesized ZnO nanosheets was sys-tematically investigated,taking formaldehyde as probe *** with commercial ZnO nanoparticles,ZnO nanosheets exhibited enhanced formaldehyde sensing properties,including lower operation temperature,higher sensitivity,faster response,and smaller detection ***,the response(S=227.4)of ZnO nanosheets to 200×10^(-6) formaldehyde is about 17 times larger than that of ZnO nanoparticles(S=13.5).Excluding effects of grain size and surface area,enhanced sensing properties,especially response value,are credited in large part to synergistic actions of surface defects,grain boundaries,as well as unique structural advantage of ZnO ***,this work offers a guideline for boosting performance of metal oxide-based gas sensors via surface defect control and grain boundary construction.

关键词： performance polycrystalline grain

Low-cost Sm0.7Y0.3Co5 sintered magnet produced by traditional powder metallurgical techniques

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Rare Metals 2020年第4期39卷 421-428页

作者： Dong-Tao zhang Nai-Xing Cai Rong-Chun Zhu Wei-Qiang Liu ming yue College of Materials Science and Engineering Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

RCo5(R=rare earth)sintered magnets have good temperature stability,so it is still widely used in high temperature *** this paper,by the method of adding liquid phase SmCo1.7 to the main phase,Sm0.7Y0.3Co5 magnet was prepared by traditional powder metallurgical *** results show the presence of a main phase RCo5,a minor phase R2 Co7,and a R-rich phase in the *** the results of the XRD(X-ray diffraction)in random and oriented directions,the magnet has a well-aligned(00l)orientated texture,which is consistent with the result of the electron backscattered diffraction(EBSD).The Sm0.7Y0.3Co5 sintered magnet has good magnetic properties as remanence(Br)is 0.96 T,the coercivity(Hcj)is 1201.96 kA·m-1,and maximum magnetic energy product((BH)max)is 175.16 kJ m-3.

关键词： Sm0.7Y0.3Co5 Sintered magnets Low-cost Magnetic properties RCo5