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Friction factor and heat transfer of nanofluid in the turbulent flow through a 90°bend

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Journal of Hydrodynamics 2021年第6期33卷 1105-1118页

作者： Pei-jie Zhang Jian-zhong Lin Xiao-ke ku Department of Mechanics State Key Laboratory of Fluid Power and Mechatronic SystemZhejiang UniversityHangzhou 310027China

Heat transfer and energy performance of Al_(2)O_(3)/water nanofluid in a 90°bend with circular cross-section are investigated in the range of Reynolds number(Re)from 5000 to 30000,particle volume concentration(Φ)from 0.005%to 4%,schmidt number(sc)from 9870 to 296100,Dean number(De)from 6636 to *** momentum and energy equations of nanofluid together with the dynamic equation for nanoparticles are solved numerically with the particle convection,diffusion,coagulation and breakage taken into *** results are validated by comparing with the available experimental or numerical *** effect of Re,Φ,sc and De on the friction factor and heat transfer of Al_(2)O_(3)/water nanofluidis *** results showed that the particle number decreases along the *** De,sc leads to a decrease and increase ofΦ,*** mean particle diameter and particle polydispersity increase with increasing Debut with decreasing *** friction factor increases with increasingΦ,sc De and Pr but with decreasing *** ratio of energy performance evaluation criterion(PEC)for the Al_(2)O_(3)/water nanofluid to the base fluid increases with increasing Re,Φand De,but with decreasing ***,the expression of ratio of energy PEC for the nanofluid to the base fluid as a function of Re,Φ,sc and De is derived.

关键词： Al_(2)O_(3)/water nanofluid friction factor heat transfer energy performance evaluation turbulent pipe flow 90°bend numerical simulation

Achieving exceptional wear resistance in a crack-free high-carbon tool steel fabricated by laser powder bed fusion without pre-heating

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Journal of Materials science & Technology 2023年第25期156卷 1-19页

作者： konrad kosiba Daniel wolf Matthias Bönisch kai Neufeld Ruben Hühne Tobias Gustmann Jozef Bednarčík Hongyu Chen Xiaoliang Han Volker Hoffmann Lukas Beyer Uta kühn Sergio scudino Lars Giebeler Julia k.Hufenbach Leibniz Institute for Solid State and Materials Research (IFw) Dresden E.V. Helmholtzstr. 20Dresden 01069Germany Department of Materials Engineering KU LeuvenKasteelpark Arenberg 44bus 2450Leuven 3001Belgium Department of Condensed Matter Physics Institute of PhysicsP.J. Safarik University in KosicePark Angelinum 9Kosice 04154Slovakia Institute of Experimental Physics Slovak Academy of ScienceWatsonova 47Kosice 040 01Slovakia key Laboratory of Impact and Safety Engineering of Ministry of Education of China Ningbo UniversityNingbo 315211China TU Bergakademie Freiberg Institute of Materials ScienceGustav-Zeuner-Str. 5Freiberg 09599Germany

Laser powder bed fusion(LPBF)for the fabrication of dense components used for tooling applications,is highly *** stresses,which evolve in the additively manufactured part,are inherent to LPBF *** additional stress contribution in high-carbon steels arises from the austenite-to-martensite phase transformation,which may eventually lead to cracking or even *** an alternative to pre-heating the base plate,which is not striven by industry,lowering the martensite content which forms in the part,is essential for the fabrication of dense parts by LPBF of high-carbon tool steels which are then adapted to *** this study,a successful strategy demonstrates the processing of the Fe85Cr4Mo1V1w8C1(wt%)high-carbon steel by LPBF into dense parts(99.8%).The hierarchical microstructure consists of austenitic and martensitic grains separated by elemental segregations in which nanoscopic carbide particles form a network.A high density of microsegregation was observed at the molten pool boundary ultimately forming a *** LPBF-fabricated steel shows a yield strength,ultimate compressive stress,and total strain of 1210 MPa,3556 MPa,and 27.4%,*** mechanical and wear performance is rated against the industrially employed and highly wear-resistant 1.2379 tool steel taken as the *** its lower macro-hardness,the LPBF steel(58.6 HRC,0.0061 mm^(3) Nm^(-1))shows a higher wear resistance than the reference steel(62.6 HRC,0.0078 mm^(3) Nm^(-1)).This behavior results from the wear-induced formation of martensite in a microscale thick layer directly at the worn surface,as it was proven via high-energy X-ray diffraction mapping.

关键词： Additive manufacturing Laser powder bed fusion Steel wear TRIP

Empirical Evidence for the Look-Ahead Behavior of Pedestrians in Bi-directional Flows

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Chinese Physics Letters 2012年第6期29卷 299-302页

作者： GUO Ren-Yong wONG sc XIA Yin-Hua HUANG Hai-Jun LAM william H.k. CHOI keechoo College of Computer science Inner Mongolia UniversityHohhot 010021 Department of Civil Engineering The University of Hong KongPokfulam RoadHong Kong Department of Mathematics University of Science and Technology of ChinaHefei 230026 school of Economics and Management Beijing University of Aeronautics and AstronauticsBeijing 100191 Department of Civil and Structural Engineering The Hong Kong Polytechnic UniversityHong Kong Department of Transportation Engineering Ajou UniversitySan 5 Woncheon-DongYeongtong-KuSuwon442-749 Korea

Using the sample data obtained from a group of pedestrian experiments,a function formulating the velocitydensity relationship of pedestrians and linear regression is proposed to provide empirical evidence for the lookahead behavior of pedestrians in bi-directional *** find that the velocity of pedestrians is negatively correlated with not only the densities of the opposite-direction and the identical-direction pedestrians around them but also the densities of the same-direction pedestrians ahead of ***,the movement of pedestrians is most affected by other pedestrians moving in the same direction about 1 m ahead.

关键词： directional identical ahead

高脂喂养对母系高血压子代小鼠代谢调节的不利影响

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中华高血压杂志 2017年第7期25卷 698-698页

作者： Longo M Refuerzo JS Mann L Leon M Moussa hn Sibai BM Blackwell sc 陈云叶鹏

该团队之前研究报道由敲除内皮型一氧化氮合酶（endothelial nitric oxide synthase,eNOS）-/-基因（eNOS-/-kO）的高血压母鼠所生的杂交子代小鼠部分缺乏eNOS基因可发生高血压。本研究推测,这些子代小鼠若以高脂喂养将会发生代谢调节... 详细信息

该团队之前研究报道由敲除内皮型一氧化氮合酶（endothelial nitric oxide synthase,eNOS）-/-基因（eNOS-/-kO）的高血压母鼠所生的杂交子代小鼠部分缺乏eNOS基因可发生高血压。本研究推测,这些子代小鼠若以高脂喂养将会发生代谢调节改变而增加其发展为代谢综合征的风险。方法：

关键词：高脂喂养代谢调节对母代谢综合征野生型小鼠胰岛素耐量试验空腹胰岛素代谢指标杂合血清脂质

Inhibitory effect of tea polyphenals on transforming growth factor-β1 expression in rat with cyclosporine A-induced chronic nephrotoxicity

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Acta Pharmacologica Sinica 2004年第1期 100-105页

作者： Shao-hua SHI, Shu-sen ZHENG, Chang-ku JIA, You-fa ZHU, Hai-yang XIEDepartment of Hepatobiliary Surgery, the First Affiliated Hospital, Medical College, Zhejiang University Department of Pathology, Medical College, Zhejiang University Institute of Surgery, Zhejiang University, Hangzhou 310003, China

AIM: To investigate the inhibitory effect of tea polyphenols (TP)on the transforming growth factor-pi (TGF-β1) expression in rat model of cyclosporine A (CsA)-induced chronic nephrotoxicity. METHODS: The rat model of CsA-induced chronic nephrotoxicity was used, 4 groups of rats were respectively treated with vehicle (0.1 mL·lg-1-d-1 sc), TP (80 mg·kg-1·d-1 ig), CsA (15 mg·2kg-1·d-1sc) and TP plus CsA (CsA 15 mg·kg-1·d-1 sc+TP 80 mg·kg-1·d-1 ig). At the end of day 28 of treatment, serum and urine are analyzed for creatinine clearance, kidney tissue for pathologic analysis. The TGF-β1 mRNA and its protein expression were detected by RT-PCR, immunohistochemistry, and western blot. RESULTS: CsA-treated rats had increased renal expression of TGF-pl mRNA and its protein, compared with the vehicle- or TP- treated

关键词： tea cyclosporine A transforming growth factor-β kidney polymerase chain reaction immunohistochemistry western blotting

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降低硅片表面微粗糙度的预氧化清洗工艺

Journal of Semiconductors 2006年第7期27卷 1331-1334页

作者：库黎明王敬周旗钢北京有色金属研究总院北京100088 清华大学微电子学研究所北京100084

利用原子力显微镜研究了预氧化清洗工艺对清洗后的硅片表面微粗糙的影响,并通过建立表面氧化过程的分子模型和氧化层模型来进行相应的机理分析.结果表明,硅片表面在含有氧化剂H2O2的溶液中生成一层氧化层后,能基本消除OH-对硅片表面的... 详细信息

利用原子力显微镜研究了预氧化清洗工艺对清洗后的硅片表面微粗糙的影响,并通过建立表面氧化过程的分子模型和氧化层模型来进行相应的机理分析.结果表明,硅片表面在含有氧化剂H2O2的溶液中生成一层氧化层后,能基本消除OH-对硅片表面的各向异性腐蚀,清洗后的表面微粗糙度比清洗前小,并且随sc-1清洗过程中NH4OH浓度的增大而减小.

关键词：预氧化氧化层各向异性腐蚀微粗糙度

Magnetic resonance evaluation of human mesenchymal stem cells in corpus cavernosa of rats and rabbits

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Asian Journal of Andrology 2007年第3期9卷 361-367页

作者： Yun-Seob Song Ja-Hyeon ku Eun-Seop Song Jung-Hoon kim Jin-Suck Jeon kong-Hee Lee Sook-Ja kim Hee-Jeong Cheong Ik-Sung Lim Dongho Choi Jong-Ho won Department of Urology Stem Cell therapy Center Soonchunhyang School of Medicine Seoul 140-743 Korea Department of Urology Seoul National University Hospital Seoul 110-744 Korea Department of Obstetrics and Gynecology Inha University School of Medicine Incheon 400-103 Korea Department of Radiology Soonchunhyang School of Medicine Seoul 140-743 Korea Department of Internal Medicine Soonchunhyang School of Medicine Seoul 140-743 Korea Department of Urology Soonchunhyang School of Medicine Seoul 140-743 Korea Stem Cell therapy Center Soonchunhyang School of Medicine Seoul 140-743 Korea Department of Industrial Management ＆ Engineering Namseoul University College of Engineering Cheonan 330-707 Korea Department of Surgery Stem Cell therapy Center Soonchunhyang School of Medicine Seoul 140-743 Korea Department of Internal Medicine Stem Cell therapy Center Soonchunhyang School of Medicine Seoul 140-743 Korea

Aim： To investigate whether the biological process of superparamagnetic iron oxide （SPIO）-labeled human mesenchymal stem cells （hMscs） may be monitored non-invasively by using in vivo magnetic resonance （MR） imaging with conventional 1.5-T system examinations in corpus cavernosa of rats and rabbits. Methods： The labeling efficiency and viability of SP10-labeled hMscs were examined with Prussian blue and Tripan blue, respectively. After SPIO-labeled hMscs were transplanted to the corpus cavernosa of rats and rabbits, serial T2-weighted MR images were taken and histological examinations were carried out over a 4-week period. Results： hMscs loaded with SPIO compared to unlabeled cells had a similar viability. For SPIO-labeled hMscs more than lx 105 concentration in vitro, MR images showed a decrease in signal intensity. MR signal intensity at the areas of SPIO-labeled hMscs in the rat and rabbit corpus cavernosa decreased and was confined locally. After injection of SPIO-labeled hMscs into the corpus cavernosum, MR imaging demonstrated that hMscs could be seen for at least 12 weeks after injection. The presence of iron was confirmed with Prussian blue staining in histological sections. Conclusion： SP10-labeled hMscs in corpus cavernosa of rats and rabbits can be evaluated non-invasively by molecular MR imaging. Our findings suggest that MR imaging has the ability to test the long-term therapeutic potential of hMscs in animals in the setting of erectile dysfunction.

关键词： human mesenchymal stem cells magnetic resonance stem cells penis cell labeling corpus cavemosa

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犬副流感病毒单克隆抗体的研制及其特性鉴定

中国预防兽医学报 2009年第12期31卷 985-987页

作者：焦库华岑皓张小荣吴艳涛扬州大学兽医学院江苏扬州225009

为研制犬副流感特异性诊断试剂,我们以犬副流感病毒(CPIV)免疫8周龄BALB/c小鼠,采用淋巴细胞杂交瘤技术获得4株稳定分泌针对CPIV的单克隆抗体(MAb)细胞株,分别命名为4F3B6、5B4C9、4G7F4和4C9D8。4株MAb腹水针对CPIV的间接ELISA抗体效价... 详细信息

为研制犬副流感特异性诊断试剂,我们以犬副流感病毒(CPIV)免疫8周龄BALB/c小鼠,采用淋巴细胞杂交瘤技术获得4株稳定分泌针对CPIV的单克隆抗体(MAb)细胞株,分别命名为4F3B6、5B4C9、4G7F4和4C9D8。4株MAb腹水针对CPIV的间接ELISA抗体效价达1:105～1:106,与犬瘟热病毒(CDV)和犬细小病毒(CPV)均不发生交叉反应。MAb4F3B6和4C9D8为IgG,5B4C9和4G7F4为IgM。western blot检测表明,4F3B6与CPIV的F蛋白发生特异性反应,4G7F4与CPIV的hn蛋白发生特异性反应,而5B4C9和4C9D8不与变性的CPIV蛋白发生反应。4株MAb均具有中和病毒活性,间接免疫荧光检测均呈为阳性。本研究为进一步研制CPIV特异性诊断和治疗制剂创造了条件。

关键词：犬副流感病毒单克隆抗体生物学特性

对精神分裂症患者血脂异常的瑞舒伐他汀辅助治疗的疗效与安全性的的Meta分析（英文）

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上海精神医学 2018年第1期30卷 4-11页

作者：郑伟杨威张庆娥杨欣湖蔡东滨胡晋卿 Ungvari.GS hn Chee Hert MD 宁玉萍项玉涛 The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital) Guangzhou China Xiamen Xian Yue Hospital Xiamen Fujian China The National Clinical Research Center for Mental Disorders & Beijing key Laboratory of Mental Disorders Beijing Anding Hospital Capital Medical University Beijing China Clinics of Chinese Medicine the First Clinical Medical College of Guangzhou University of Chinese Medicine Guangzhou China The University of Notre Dame Australia / Marian Centre & Graylands Hospital Perth Australia Department of Psychiatry University of Melbourne Melbourne Victoria Australia Universitair Psychiatrisch Centrum KU Leuven Leuven Belgium Department of Neurosciences KU Leuven Belgium Unit of Psychiatry Faculty of Health Sciences University of Macao Macao SAR China

背景:精神分裂症患者的代谢综合征是一个重要的健康问题。瑞舒伐他汀对血脂异常的辅助性治疗的有效性和安全性存在争议。目的:评价瑞舒伐他汀对精神分裂症患者血脂异常的辅助性治疗的有效性和安全性。方法:我们从以下数据库中系统地检索... 详细信息

背景:精神分裂症患者的代谢综合征是一个重要的健康问题。瑞舒伐他汀对血脂异常的辅助性治疗的有效性和安全性存在争议。目的:评价瑞舒伐他汀对精神分裂症患者血脂异常的辅助性治疗的有效性和安全性。方法:我们从以下数据库中系统地检索了2017年9月28日以前相关的临床对照试验:Pub Med、Psyc INFO、Cochrane图书馆、中国知网、万方数据库、中国生物医学文献数据库。我们计算了标准平均差(SMD)、风险比(RR)及其95%的可信区间(CIs)。使用偏移评估工具中的Cochrane风险评估来评价所纳入研究的质量。并采用GRADE系统推荐的等级方法(推荐、评估、发展、评价的等级)作为参照标准。结果:确认和分析了4项比较瑞舒伐他汀组(n=138)和对照组(n=136)的研究(n=274)。瑞舒伐他汀辅助治疗显示对低密度脂蛋白胆固醇(LDL-C)[4项试验,n=272,SMD:-1.31(95%CI:-1.93,-0.70),I^2=81%]、总胆固醇(2项试验,n=164,SMD:-2.00(95%CI:-2.79,-1.21);I^2=76%)、和甘油三酯(2项试验,n=164,SMD:-1.05(95%CI:-1.38,-0.72);I^2=0%)的疗效比对照组更有效,但对高密度脂蛋白胆固醇(2项试验,n=164,SMD:0.14(95%CI:-0.16,0.45);I^2=0%)的疗效没有显著差异。去除一项没有随机试验的LDL-C研究之后,显著差异仍然存在[3项试验,n=172,SMD:-1.07(95%CI:-1.60,-0.53);I^2=63%]。体重(3项试验,n=208,SMD:-0.40(95%CI:-1.29,0.49);I^2=89%)、身体质量指数(2项试验,n=164,SMD:-0.34(95%CI:-1.23,0.56);I^2=87%)、腰围(3项试验,n=208,SMD:-0.43(95%CI:-1.31,0.46);I^2=89%)、空腹血糖(4项试验,n=272,SMD:-0.25(95%CI:-0.65,0.15);I^2=62%)方面组间没有显著的差异。两组之间的不良反应及停药率相近。根据GRADE分级方法,主要结果的证据水平低被评为"非常低"(35.3%)到"低"(64.7%)。其中,主要结果(LDL-C)被评为"非常低"。结论:对精神分裂症患者血脂异常的瑞舒伐他汀辅助性治疗的现有数据尚不足以对其有效性和安全性做出明确的解释。需进一步针对高质量的延长治疗时间的随机对照试验来验证该结论。

关键词：精神分裂症瑞舒伐他汀血脂异常低密度脂蛋白胆固醇 Meta分析