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Fluid−Structure Interaction of Two-Phase Flow Passing Through 90° Pipe Bend Under Slug Pattern Conditions

China Ocean Engineering 2021年第6期35卷 914-923页

作者： WANG zhi-wei HE Yan-ping li ming-zhi QIU ming HUANG Chao liU Ya-dong WANG Zi State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Naval Architecture Ocean&Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Institute of Marine Equipment Shanghai Jiao Tong UniversityShanghai 200240China COSCO SHIPPING(Qidong)Offshore Co.Ltd QidongChina

Numerical simulations of evolution characteristics of slug flow across a 90°pipe bend have been carried out to study the fluid−structure interaction response induced by internal slug *** two-phase flow patterns and turbulence were modelled by using the volume of fluid(VOF)model and the Realizable k−εturbulence model ***,validation of the CFD model was carried out and the desirable results were *** different flow patterns and the time-average mean void fraction was coincident with the reported experimental *** of different cases of slug flow have been carried out to show the effects of superficial gas and liquid velocity on the evolution characteristics of slug ***,a one-way coupled fluid-structure interaction framework was established to investigate the slug flow interaction with a 90°pipe bend under various superficial liquid and gas *** was found that the maximum total deformation and equivalent stress increased with the increasing superficial gas velocity,while decreased with the increasing superficial liquid *** addition,the total deformation and equivalent stress has obvious periodic ***,the distribution position of maximum deformation and stress was related to the evolution of slug *** the increasing superficial gas velocity,the maximum total deformation was mainly located at the 90°pipe *** as the superficial liquid velocity increases,the maximum total deformation was mainly located in the horizontal pipe ***,the slug flow with higher superficial gas velocity will induce more serious cyclical impact on the 90°pipe bend.

关键词： two-phase flow 90°pipe bend slug flow fluid−structure interaction dynamic response characteristics

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A New Dimeric Phthalide from Angelica sinensis

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Chinese Chemical Letters 2006年第12期17卷 1579-1581页

作者： ling YI Ping li zhi ming BI Key Laboratory of Modem Chinese Medicines Ministry of Education and Department of Pharmacognosy China Pharmaceutical University Nanjing 210009

A new dimeric phthalide named Z, Z＇-3.3＇a, 7.7＇a-diligustilide was isolated from the roots of Angelica sinensis. Its structure was determined using spectroscopic methods and X-ray crystallographic diffraction analy... 详细信息

关键词： Angelica sinensis dimeric phthalide X-ray diffraction.

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New C(21) steroidal glycoside from Cynanchum paniculatum

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Chinese Chemical Letters 2007年第3期18卷 300-302页

作者： Jing Dou Ping li zhi ming Bi Jian liang Zhou Ministry of Education Key Laboratory of Modern Chinese Medicines Department of Pharmacognosy China Pharmaceutical University Nanjing 210038 China

A new C21 steroidal glycoside, neocynapanogenin F 3-O-β-D-thevetoside 1, as well as its known aglycone neocynapanogenin F 2, which have an aberrant 13, 14：14, 15-disecopregnane-type skeleton were isolated from the root of Cynanchum paniculatum. Their structures were elucidated on the basis of spectroscopic data analysis. These compounds showed certain cytotoxic activities in vitro.

关键词： Neocynapanogenin F 3-O-β-D-thevetoside Neocynapanogenin F Cynanchum paniculatum

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Path Planning Method Based on D^(*) lite Algorithm for Unmanned Surface Vehicles in Complex Environments

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China Ocean Engineering 2021年第3期35卷 372-383页

作者： YAO Yan-long liANG Xiao-feng li ming-zhi YU Kai CHEN Zhe NI Chong-ben TENG Yue State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Marine Intelligent Equipment and System of Ministry of Education Shanghai Jiao Tong UniversityShanghai 200240China Joint Institute Shanghai Jiao Tong UniversityShanghai 200240China

In recent decades,path planning for unmanned surface vehicles(USVs)in complex environments,such as harbours and coastlines,has become an important *** existing algorithms for real-time path planning for USVs are either too slow at replanning or unreliable in changing environments with multiple dynamic *** this study,we developed a novel path planning method based on the D^(*) lite algorithm for real-time path planning of USVs in complex *** proposed method has the following advantages:(1)the computational time for replanning is reduced significantly owing to the use of an incremental algorithm and a new method for modelling dynamic obstacles;(2)a constrained artificial potential field method is employed to enhance the safety of the planned paths;and(3)the method is practical in terms of vehicle *** performance of the proposed method was evaluated through simulations and compared with those of existing *** simulation results confirmed the efficiency of the method for real-time path planning of USVs in complex environments.

关键词： path planning unmanned surface vehicle D^(*)lite algorithm complex environment

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Temperature Uniformity of Wafer on a Large-Sized Susceptor for a Nitride Vertical MOCVD Reactor

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Chinese Physics Letters 2012年第3期29卷 52-55页

作者： li zhi-ming JIANG Hai-Ying HAN Yan-Bin li Jin-Ping YIN Jian-Qin ZHANG Jin-Cheng Shandong Provincial Key Laboratory of Network-Based Intelligent Computing School of Information Science and EngineeringUniversity of Ji’nanJi’nan 250022 Key Laboratory of Fundamental Science for National on Wide Band-Gap Semiconductor Technology School of MicroelectronicsXidian UniversityXi’an 710071

The effect of coil location on wafer temperature is analyzed in a vertical MOCVD reactor by induction *** is observed that the temperature distribution in the wafer with the coils under the graphite susceptor is more uniform than that with the coils around the outside wall of the *** the case of coils under the susceptor,we find that the thickness of the susceptor,the distance from the coils to the susceptor bottom and the coil turns significantly affect the temperature uniformity of the *** optimization process is executed for a 3-inch susceptor with this kind of structure,resulting in a large improvement in the temperature uniformity.A further optimization demonstrates that the new susceptor structure is also suitable for either multiple wafers or large-sized wafers approaching 6 and 8 inches.

关键词： MOCVD optimization Vertical

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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

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急曲线隧道盾构超挖量及铰接角的理论算法

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中国公路学报 2017年第8期30卷 66-73页

作者：陈剑李智明哈尔滨工业大学结构工程灾变与控制教育部重点实验室黑龙江哈尔滨150090 哈尔滨工业大学土木工程智能防灾减灾工业和信息化部重点实验室黑龙江哈尔滨150090

为提高盾构机开挖急曲线隧道的能力,应准确预估超挖刀的伸出长度与范围、铰接角等几何作业参数。目前上述参数仅基于盾构与隧道设计轴线的平面几何关系确定,无法适应三维复合曲线隧道的施工要求。基于空间向量分析理论,提出三维复合曲... 详细信息

为提高盾构机开挖急曲线隧道的能力,应准确预估超挖刀的伸出长度与范围、铰接角等几何作业参数。目前上述参数仅基于盾构与隧道设计轴线的平面几何关系确定,无法适应三维复合曲线隧道的施工要求。基于空间向量分析理论,提出三维复合曲线隧道超挖刀长度与范围、铰接角的理论算法,并基于Fortran语言实现算法的求解。对实际隧道工程盾构的几何作业参数进行了模拟,通过模拟值与实测数据的对比,验证了理论算法的有效性。结果表明:铰接角的实测值与模拟值整体拟合较好,当盾构机在曲线段掘进时,铰接角的实测值略大于模拟值,是由于实际施工中以刀盘的中心点拟合隧道设计轴线为纠偏目标,与理论算法中以管片拼装中心点拟合隧道轴线的理想掘进状态存在差异;模拟的超挖刀范围窄于实测范围,而超挖刀伸出长度的模拟值比实测值略大,存在的微小差异来自于理论算法假定盾构机不挤压地层且周围地层不变形,而实际施工中地层存在一定的变形量。

关键词：盾构隧道曲线开挖超挖铰接角向量分析

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Comparative analysis of different methods for image enhancement

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Journal of Central South University 2014年第12期21卷 4563-4570页

作者：吴笑峰胡仕刚赵瑾李志明李劲唐志军席在芳 School of Information and Electrical Engineering Hunan University of Science and Technology School of Information Science and Engineering University of Jinan

Image enhancement technology plays a very important role to improve image quality in image processing. By enhancing some information and restraining other information selectively, it can improve image visual effect. The objective of this work is to implement the image enhancement to gray scale images using different techniques. After the fundamental methods of image enhancement processing are demonstrated, image enhancement algorithms based on space and frequency domains are systematically investigated and compared. The advantage and defect of the above-mentioned algorithms are analyzed. The algorithms of wavelet based image enhancement are also deduced and generalized. Wavelet transform modulus maxima(WTMM) is a method for detecting the fractal dimension of a signal, it is well used for image enhancement. The image techniques are compared by using the mean(μ),standard deviation(?), mean square error(MSE) and PSNR(peak signal to noise ratio). A group of experimental results demonstrate that the image enhancement algorithm based on wavelet transform is effective for image de-noising and enhancement. Wavelet transform modulus maxima method is one of the best methods for image enhancement.

关键词： image enhancement wavelet transform histogram equalization unsharp masking(UM) modulus maxl mum threshold

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Human umbilical cord-derived endothelial progenitor cells promote growth cytokines-mediated neorevascularization in rat myocardial infarction

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Chinese Medical Journal 2009年第5期122卷 548-555页

作者： HU Cheng-heng li zhi-ming DU zhi-min ZHANG Ai-xia YANG Da-ya WU Gui-fu Division of Cardiology First Affiliated Hospital and Key Laboratory on Assisted Circulation Ministry of Health of China Sun Yat-sen University Guangzhou Guangdong 510080 China

Background Cell-based vascular therapies of endothelial progenitor cells （EPCs） mediated neovascularization is still a novel but promising approach for the treatment of ischemic disease. The present study was designed to investigate the therapeutic potentials of human umbilical cord blood-derived EPCs （hUCB-EPCs） in rat with acute myocardial infarction. Methods Human umbilical cord blood （hUCB） mononuclear cells were isolated using density gradient centrifugation from the fresh human umbilical cord in healthy delivery woman, and cultured in M199 medium for 7 days. The EPCs were identified by double-positive staining with 1,1＇-dioctadecyl-3,3,3＇,3＇-tetramethylindocarbocyanine percholorate-labeled acetylated low-density lipoprotein （DiI-Ac-LDL） and fluorescein isothiocyanate-conjugated Ulex europaeus lectin （FITC-UEA-I）. The rat acute myocardial infarction model was established by the ligation of the left anterior descending artery. The hUCB-EPCs were intramyocardially injected into the peri-infarct area. Four weeks later, left ventricular function was assessed by a pressure-volume catheter. The average capillary density （CAD） was evaluated by anti-VIII immunohistochemistry staining to reflect the development of neovascularization at the peri-infarct area. The graft cells were identified by double immunofluorescence staining with human nuclear antigen （HNA） and CD31 antibody, representing human origin of EPCs and vascular endothelium, respectively. Expressions of cytokines, proliferating cell nuclear angigen （PCNA）, platelet endothelial cell adhesion molecule （PECAM） and vascular endothelial growth factor （VEGF） were detected to investigate the underlying mechanisms of cell differentiation and revascularization. Results The donor EPCs were detectable and integrated into the host myocardium as confirmed by double-positive immunofluorescence staining with HNA and CD31. And the anti-VIII staining demonstrated a higher degree of microvessel formation in EPCs transplanted

关键词： human umbilical cord blood endothelial progenitor cells acute myocardial infarction neovascularization

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The mechanism of samarium-catalyzed 1,5-Regioselective Azide-Alkyne[3+2]-Cyloaddition: A quantum mechanical investigation

The mechanism of samarium-catalyzed 1,5-Regioselective Azide...

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中国化学会第十二届全国量子化学会议

作者： WANG Jing-Mei li zhi-ming Department of chemistry Fudan University

Samarium‐catalyzed1,5‐regioselective azide‐alkyne[3+2]‐cycloaddition,as the first example of rare earth metal‐catalyzed cycloaddition of terminal alkynes to azides resulting in the formation of 1,5‐disubstituted 1,2,3‐triazoles,is a worthy supplement to the famous"clikck reaction"[1‐2].In the present work,the reaction mechanisms have been proposed and validated with DFT computations both in the gas and solution phase using Gaussian09 software at B3LYP/6‐31++G（d,p）（ECP51MWB）***,the novel quantitative analysis of molecular surface also has also been applied to explain the mechanism and regioselectivity of the title reaction[3].Based on our computation,the present cycloaddition mechanism for the title reaction favors the step‐wise pathway（COM‐COM1‐COM2‐COMP）over the concerted one（Scheme 1）.In the stepwise pathway,the step linking COM and COM1 is the rate‐determining *** addition,the reaction regioselectivity is controlled by the structures of the two Sm complexes（Fig.1）which can be well explained by the analysis of ESP on vd W surface of the reactants（Fig.2）.

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