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Bainite isothermal transformation of Si–Mn–Mo alloy by phase structure factor calculation under different rare earth contents

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Rare Metals 2014年第4期33卷 427-432页

作者： Yan-Liang yi yi-long Liang Qi-Bing Tan The Key Laboratory for Mechanical Behavior and Microstructure of Materials School of Materials and MetallurgyGuizhou University

The effect of rare earth （RE） on bainite trans- formation mechanism is not yet unified in the academia. Therefore, further studying the effect of RE on bainite transformation mechanism will have important guiding significance for the development of bainite steels. In this paper, using differential dilatometer （DIL805A/D）, heat treatment was performed and C-curve was drawn. The effect of phase structure factor on bainite transformation under two different fractions of RE in Si-Mn-Mo bainite steels was investigated by the empirical electron theory （EET） of solids, molecules, dilatometry, and metallogra- phy. Experimental results show that RE makes Fe-C- RE segregation structural unit of Si-Mn-Mo bainite steels increase, i.e., the values of phase structure factor （na, FDC） increase, and delay bainite transformation due to the drag effect resulting from the segregation of RE ferrite island interphase and the retardation of RE to carbon diffusion in Si-Mn-Mo bainite steels. Beside this, C-curve is shifted to right and down, and microstructures of bainite ferrite and substructures are finer.

关键词： Phase structure factor C-curve Substructure Rare earths

Nanopore sensing system for high-throughput single molecular analysis

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Science China Chemistry 2018年第12期61卷 1483-1485页

作者： Zhen Gu yi-Lun ying yi-Tao long Key Laboratory for Advanced Materials & School of Chemistry and Molecular EngineeringEast China University of Science and Technology Shanghai 200237China

Nanopore technique enables a sensitive, label free, low cost and high throughput method for single-molecule analysis[1–4]. Usually, the nanopore is fabricated on an insulating membrane with electrolyte solution in two sides, which can act as the only pathway for the ionic flow. When a single molecule enters the pore under the applied biased potential, it will temporarily block the ionic current flow through the nanopore. By analyzing the amplitude, duration, shape and frequency spectra of ionic current modulations, nanopore detection could provide the characteristics of the analytes.

关键词： Nanopore sensing system high-throughput single molecular analysis

Influences of pore fluid on gas production from hydrate-bearing reservoir by depressurization

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Petroleum Science 2023年第2期20卷 1238-1246页

作者： yi-Fei Sun Bo-Jian Cao Hong-Nan Chen yin-long Liu jin-Rong Zhong Liang-Liang Ren Guang-jin Chen Chang-Yu Sun Dao-yi Chen State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Division of Ocean Science and Technology Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhenGuangdong 518055China School of Chemistry and Food Engineering Changsha University of Science&TechnologyChangshaHunan 410114China Oilfield Chemicals R&D Institute COSLHebei 065201China

In addition to the temperature and pressure conditions,the pore fluid composition and migration behavior are also crucial to control hydrate decomposition in the exploitation *** this work,to investigate the effects of these factors,a series of depressurization experiments were carried out in a visible one-dimensional reactor,using hydrate reservoir samples with water saturations ranging from 20%to 65%.The results showed a linear relationship between gas production rates and gas saturations of the reservoir,suggesting that a larger gas-phase space was conducive to hydrate decomposition and gas ***,the rapid water production in the early stage of hydrate exploitation could release more gas-phase space in the water-rich reservoir,which in turn improved the gas production ***,the spatiotemporal evolution of pore fluids could lead to partial accelerated decomposition or secondary formation of *** the unsealed reservoir,the peripheral water infiltration kept reservoir at a high water saturation,which hindered the overall production process and caused higher water ***,depressurization assisted with the N2 sweep could displace the pore water *** to the results,it is recommended that using the short-term N2 sweep as an auxiliary means in the early stage of depressurization to expand the gas-phase space in order to achieve the highest production efficiency.

关键词： CH4 hydrate Water saturation Depressurization Gas-phase space N2 sweep

Fission and Fusion of Localized Coherent Structures for a Higher-Order Broer-Kaup System

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Communications in Theoretical Physics 2005年第6期43卷 993-997页

作者： MAZheng-yi ZHENGChun-long DepartmentofMathematics ZhejiangLishuiUniversityLishui323000China DepartmentofMathematics ZhejiangLishuiUniversityLishui323000China／／ShanghaiInstituteofAppliedMathematicsandMechanicsShanghaiUniversityShanghai200072China

Starting from a Backlund transformation and taking a special ansatz for the function f, we can obtain a much more generalexpression of solution that includes some variable separated functions for the higher-order Broer-Kaup system. From this expression, we investigate the interactions of localized coherent structures such as the multi-solitonic excitations and find the novel phenomenon that their interactions have non-elastic behavior because the fission/fusion may occur after the interaction of each localized coherent structure.

关键词： higher-order Broer-Kaup system variable separation approach Backlund transformation soliton fission soliton fusion

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乳腺MR检查的常见伪影及解决方案

现代生物医学进展 2011年第S2期11卷 5128-5130页

作者：汪黎黎陈蓉陈金华张玉龙易元月第三军医大学大坪医院野战外科研究所放射科重庆400042

目的:分析乳腺MR检查中的常见伪影,探讨合理的解决方案,以提高乳腺MR图像质量及诊断准确性。方法:随机抽取我院100例行乳腺MR检查的图像资料,观察图像中出现的各种伪影及其表现,分析其产生的原因和影响因素。结果:乳腺MR图像的影像细节... 详细信息

目的:分析乳腺MR检查中的常见伪影,探讨合理的解决方案,以提高乳腺MR图像质量及诊断准确性。方法:随机抽取我院100例行乳腺MR检查的图像资料,观察图像中出现的各种伪影及其表现,分析其产生的原因和影响因素。结果:乳腺MR图像的影像细节显示能力较强,图像质量与扫描技术关系密切,影响图像质量的常见伪影有:硬件相关伪影、图像处理相关伪影、运动相关伪影。结论:加强MR设备的使用管理,选择合理的扫描序列及参数,做好乳腺MR扫描的检查前准备及扫描,有助于提高乳腺病变的检出率。

关键词：乳腺磁共振伪影质量控制

In situ deformation behavior of TC21 titanium alloy with different α morphologies(equiaxed/lamellar)

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Rare Metals 2021年第5期40卷 1173-1181页

作者： Wei long Mei-Gui Ou Xi-Qin Mao yi-long Liang College of Materials and Metallurgy Guizhou UniversityGuiyang 550025China Key Laboratory for Materials Structure and Strength of Guizhou Province Guizhou UniversityGuiyang 550025China National Local Joint Engineering Laboratory for High Performance Metal Structure Materials and Manufacturing Technology Guizhou UniversityGuiyang 550025China

To study the effect ofαphase morphology(equiaxedα(αE)/lamellarα(αL))on the in situ tensile behavior of TC21 alloy,the slip band,dislocation,crack initiation,and propagation were analyzed by scanning electron microscopy(SEM)with in situ tensile stage and transmission electron microscopy(TEM).The results show that the slip bands first concentrate in theαE phases and easily truncate at theα/βphase boundaries,whereas the slip bands move across theαlamellae in theαL *** are easily generated inαE orα/βphase boundaries with large plastic *** the quantity ofαL is more thanαE,the crack tip is more easily deflected atαphases orαclusters with different orientations,making the main crack propagation path more *** the volume fraction ratio ofαE toαL is~3:4,i.e.,the volume fraction ofαE is close to that ofαL,TC21 alloy exhibits better strength and slower crack propagation rate.

关键词： In situ tensile TC21 alloy Equiaxed Lamellar αPhase

Enhanced deposition of Zn O films by Li doping using radio frequency reactive magnetron sputtering

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International Journal of Minerals,Metallurgy and Materials 2015年第10期22卷 1108-1114页

作者： Liang-xian Chen Sheng Liu Cheng-ming Li yi-chao Wang jin-long Liu Jun-jun Wei Institute for Advanced Materials and Technology University of Science and Technology Beijing School of Electrical and Computer Engineering RMIT University

Radio frequency(RF) reactive magnetron sputtering was utilized to deposit Li-doped and undoped zinc oxide(Zn O) films on silicon wafers. Various Ar/O2 gas ratios by volume and sputtering powers were selected for each deposition process. The results demonstrate that the enhanced Zn O films are obtained via Li doping. The average deposition rate for doped Zn O films is twice more than that of the undoped films. Both atomic force microscopy and scanning electron microscopy studies indicate that Li doping significantly contributes to the higher degree of crystallinity of wurtzite–Zn O. X-ray diffraction analysis demonstrates that Li doping promotes the(002) preferential orientation in Li-doped Zn O films. However, an increase in the Zn O lattice constant, broadening of the(002) peak and a decrease in the peak integral area are observed in some Li-doped samples, especially as the form of Li2 O. This implies that doping with Li expands the crystal structure and thus induces the additional strain in the crystal lattice. The oriented-growth Li-doped Zn O will make significant applications in future surface acoustic wave devices.

关键词： zinc oxide thin films doping deposition magnetron

A Survey on Graph Processing Accelerators:Challenges and Opportunities

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Journal of Computer Science & Technology 2019年第2期34卷 339-371页

作者： Chuang-yi Gui long Zheng Bingsheng He Cheng Liu Xin-Yu Chen Xiao-Fei Liao Hai jin National Engineering Research Center for Big Data Technology and System School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China Services Computing Technology and System Laboratory School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China Cluster and Grid Computing Laboratory School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China School of Computing National University of Singapore Singapore 117418 Singapore Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China

Graph is a well known data structure to represent the associated relationships in a variety of applications,e.g.,data science and machine *** a wealth of existing efforts on developing graph processing systems for improving the performance and/or energy efficiency on traditional architectures,dedicated hardware solutions,also referred to as graph processing accelerators,are essential and emerging to provide the benefits significantly beyond what those pure software solutions can *** this paper,we conduct a systematical survey regarding the design and implementation of graph processing ***,we review the relevant techniques in three core components toward a graph processing accelerator:preprocessing,parallel graph computation,and runtime *** also examine the benchmarks and results in existing studies for evaluating a graph processing ***,we find that there is not an absolute winner for all three aspects in graph acceleration due to the diverse characteristics of graph processing and the complexity of hardware *** finally present and discuss several challenges in details,and further explore the opportunities for the future research.

关键词： graph processing accelerator domain-specific architecture performance energy efficiency

The Existence of Two Closed Characteristics on Every Compact Star-shaped Hypersurface in R^4

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Acta Mathematica Sinica,English Series 2016年第1期32卷 40-53页

作者： Hui LIU yi Ming long School of Mathematical Sciences University of Science and Technology of China Chern Institute of Mathematics and LPMC Nankai University

Recently, Cristofaro-Gardiner and Hutchings proved that there exist at least two closed characteristics on every compact star-shaped hypersuface in R4. Then Ginzburg, Hein, Hryniewicz, and Macarini gave this result a second proof. In this paper, we give it a third proof by using index iteration theory, resonance identities of closed characteristics and a remarkable theorem of Ginzburg et at.

关键词： Compact star-shaped hypersurface closed characteristic Hamiltonian systems resonanceidentity multiplicity