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On the reliability of nanoindentation hardness of Al₂O₃ films grown on Si-wafer by atomic layer deposition

JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A 2014年第1期32卷

作者： liu, xuwen Haimi, Eero Hannula, Simo-Pekka Ylivaara, Oili M. E. Puurunen, Riikka L. Aalto Univ Sch Chem Technol Dept Mat Sci & Engn FI-00076 Espoo Finland VTT Tech Res Ctr Finland FI-02044 Espoo Finland

The interest in applying thin films on Si-wafer substrate for microelectromechanical systems devices by using atomic layer deposition (ALD) has raised the demand on reliable mechanical property data of the films. This study aims to find a quick method for obtaining nanoindentation hardness of thin films on silicon with improved reliability. This is achieved by ensuring that the film hardness is determined under the condition that no plastic deformation occurs in the substrate. In the study, ALD Al2O3 films having thickness varying from 10 to 600 nm were deposited on a single-side polished silicon wafer at 300 degrees C. A sharp cube-corner indenter was used for the nanoindentation measurements. A thorough study on the Si-wafer reference revealed that at a specific contact depth of about 8 nm the wafer deformation in loading transferred from elastic to elastic-plastic state. Furthermore, the occurrence of this transition was associated with a sharp increase of the power-law exponent, m, when the unloading data were fitted to a power-law relation. Since m is only slightly material dependent and should fall between 1.2 and 1.6 for different indenter geometry having elastic contact to common materials, it is proposed that the high m values are the results from the inelastic events during unloading. This inelasticity is linked to phase transformations during pressure releasing, a unique phenomenon widely observed in single crystal silicon. Therefore, it is concluded that m could be used to monitor the mechanical state of the Si substrate when the whole coating system is loaded. A suggested indentation depth range can then be assigned to each film thickness to provide guidelines for obtaining reliable property data. The results show good consistence for films thicker than 20 nm and the nanoindentation hardness is about 11 GPa independent of film thickness. (C) 2014 American Vacuum Society.

关键词： Thin films

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Aluminum oxide from trimethylaluminum and water by atomic layer deposition: The temperature dependence of residual stress, elastic modulus, hardness and adhesion

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THIN SOLID FILMS 2014年第0期552卷 124-135页

作者： Ylivaara, Oili M. E. liu, xuwen Kilpi, Lauri Lyytinen, Jussi Schneider, Dieter Laitinen, Mikko Julin, Jaakko Ali, Saima Sintonen, Sakari Berdova, Maria Haimi, Eero Sajavaara, Timo Ronkainen, Helena Lipsanen, Harri Koskinen, Jari Hannula, Simo-Pekka Puurunen, Riikka L. VTT Tech Res Ctr Finland FI-02044 Espoo Finland Aalto Univ Sch Chem Technol Dept Mat Sci & Engn FI-00076 Aalto Finland Fraunhofer IWS Dresden D-01277 Dresden Germany Univ Jyvaskyla Dept Phys FI-40014 Jyvaskyla Finland Aalto Univ Sch Elect Engn Dept Micro & Nanosci FI-00076 Aalto Finland Aalto Univ Sch Chem Technol Dept Mat Sci & Engn FI-00076 Aalto Finland Aalto Univ Sch Chem Technol Micronova Nanofabricat Ctr FI-00076 Aalto Finland

Use of atomic layer deposition (ALD) in microelectromechanical systems (MEMS) has increased as ALD enables conformal growth on 3-dimensional structures at relatively low temperatures. For MEMS device design and fabrication, the understanding of stress and mechanical properties such as elastic modulus, hardness and adhesion of thin film is crucial. In this work a comprehensive characterization of the stress, elasticmodulus, hardness and adhesion of ALD aluminum oxide (Al2O3) films grown at 110-300 degrees C from trimethylaluminum and water is presented. Film stress was analyzed by wafer curvature measurements, elastic modulus by nanoindentation and surface-acoustic wave measurements, hardness by nanoindentation and adhesion by microscratch test and scanning nanowear. The films were also analyzed by ellipsometry, optical reflectometry, X-ray reflectivity and time-of-flight elastic recoil detection for refractive index, thickness, density and impurities. The ALD Al2O3 films were under tensile stress in the scale of hundreds of MPa. The magnitude of the stress decreased strongly with increasing ALD temperature. The stress was stable during storage in air. Elastic modulus and hardness of ALD Al2O3 saturated to a fairly constant value for growth at 150 to 300 degrees C, while ALD at 110 degrees C gave softer films with lower modulus. ALD Al2O3 films adhered strongly on cleaned silicon with SiOx termination. (C) 2013 Elsevier B.V. All rights reserved.

关键词： Atomic layer deposition Residual stress Elastic modulus Hardness Adhesion Aluminum oxide

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SLP Approach Based Facility Layout Optimization:An Empirical Study

SLP Approach Based Facility Layout Optimization:An Empirical...

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2016管理与组织国际会议

作者： Weiying Chen Changyu liu xuwen Huang Hualiang Lai Binfeng Li College of Mathematics and Informatics South China Agricultural University Konka Group Limited by Share Ltd

Favorable facility layouts could effectively improve production efficiency, reduce production cost, and improve comprehensive competitiveness. Take the inefficient workshop facility layout of the H Company as an example, the paper studies both transportation and processing cycle for raw materials of its main products, records statistically transport distances and transport weights for each raw material in each processing workshop, and discovers principal issues in the transportation and processing cycle for the H Company. This paper adopts the Systematic Layout Planning(SLP) approach to optimize the layout design of the H Company, and compares non-optimized layout scheme with optimized one from qualitative and quantitative analysis aspect by using the analytic hierarchy process approach. The results show that the application of SLP approach in the H Company could enhance obviously the performance of its workshop facility layout.

关键词： Systematic Layout Planning(SLP) Facility Layout Optimization Empirical Study Analytic Hierarchy Process

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Thermal and plasma enhanced atomic layer deposition of SiO₂ using commercial silicon precursors

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THIN SOLID FILMS 2014年 558卷 93-98页

作者： Putkonen, Matti Bosund, Markus Ylivaara, Oili M. E. Puurunen, Riikka L. Kilpi, Lauri Ronkainen, Helena Sintonen, Sakari Ali, Saima Lipsanen, Harri liu, xuwen Haimi, Eero Hannula, Simo-Pekka Sajavaara, Timo Buchanan, Iain Karwacki, Eugene Vaha-Nissi, Mika VTT Tech Res Ctr Finland FI-02044 Espoo Finland Aalto Univ Sch Chem Technol Inorgan Chem Lab FI-00076 Espoo Finland Beneq Oy FI-01510 Vantaa Finland Aalto Univ Sch Elect Engn Dept Micro & Nanosci FI-00076 Espoo Finland Aalto Univ Sch Chem Technol Dept Mat Sci & Engn FI-00076 Espoo Finland Univ Jyvaskyla Dept Phys FI-40014 Jyvaskyla Finland Air Prod & Chem Inc Allentown PA 18195 USA

In this paper, we report ALD deposition of silicon dioxide using either thermal or plasma enhanced atomic layer deposition (PEALD). Several aminosilanes with differing structures and reactivity were used as silicon precursors in R&D single wafer ALD tools. One of the precursors was also tested on pilot scale batch ALD using O-3 as oxidant and with substrates measuring 150 x 400 mm. The SiO2 film deposition rate was greatly dependent on the precursors used, highest values being 1.5-2.0 angstrom/cycle at 30-200 degrees C for one precursor with an O-2 plasma. According to time-of-flight-elastic recoil detection analysis measurements carbon and nitrogen impurities were relatively low, but hydrogen content increased at low deposition temperatures. (C) 2014 Elsevier B.V. All rights reserved.

关键词： Atomic layer deposition Plasma-enhanced atomic layer deposition Precursors Silicon dioxide Batch deposition Conformal coating

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Misdiagnosis of a Patient with Internal Carotid Artery Fenestration: A Case Report and Literature Review

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ANNALS OF VASCULAR SURGERY 2016年 30卷 309.e1-309.e4页

作者： Liang, Zhigang Xiu, Chunming liu, Zhuli Sun, xuwen Yu, Guoping Tao, Manli Li, Wei Qingdao Univ Coll Med Affiliated Yantai Yuhuangding Hosp Dept Neurol Yantai Shandong Peoples R China Capital Med Univ Beijing Tiantan Hosp Dept Neurol Beijing Peoples R China

Background: Internal carotid artery fenestration is a rare congenital cerebrovascular condition and can be misdiagnosed as carotid artery dissection. Case Report: A patient was initially misdiagnosed with carotid artery dissection. This initial diagnosis was made using a carotid vascular computed angiography and magnetic resonance angiography. A digital subtraction angiography examination revealed a fenestration in the terminal C1 segment of the right internal carotid artery. Previous literature related to carotid artery fenestration was reviewed and analyzed. Conclusions: Fenestration of the carotid artery combined with aneurysm at the external segment of the internal carotid artery or from the starting position of the carotid artery remains rare in elderly patients, can be misdiagnosed as artery dissection.

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离子交换树脂吸附黄连素废水中铜离子的研究

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环境工程技术学报 2017年第2期7卷 181-187页

作者：崔晓宇何绪文单永平曾萍刘瑞霞孙晨中国矿业大学(北京)化学与环境工程学院北京100083 环境基准与风险评估国家重点实验室中国环境科学研究院北京100012 中国环境科学研究院城市水环境科技创新基地北京100012 德国亥姆霍兹环境研究中心环境微生物学院莱比锡04318

以Cu^(2+)-黄连素混合体系的含铜制药废水为研究对象,考察3种离子交换树脂(D152、D113和D401)对含铜废水中Cu^(2+)和黄连素的吸附性能并对树脂进行了筛选,对D401树脂进行了吸附动力学和吸附热力学拟合分析,同时考察该树脂在黄连素竞争... 详细信息

以Cu^(2+)-黄连素混合体系的含铜制药废水为研究对象,考察3种离子交换树脂(D152、D113和D401)对含铜废水中Cu^(2+)和黄连素的吸附性能并对树脂进行了筛选,对D401树脂进行了吸附动力学和吸附热力学拟合分析,同时考察该树脂在黄连素竞争吸附影响下对Cu^(2+)的去除效果。最后,在静态试验基础上开展了动态试验,考察D401树脂柱在3种流速[1、2和5 BV(柱体积)/h]下,进样量为1~20 BV时出水的Cu^(2+)和黄连素浓度。结果表明:D401树脂的比吸附量随温度升高而增加,随树脂投加量的增加而降低;该树脂在较宽的pH范围内对Cu^(2+)具有很好的选择吸附性,pH为5.0是最佳吸附条件,此时比吸附量可达39.87 mg/g。吸附过程可以通过Langmuir吸附等温线和伪二级动力学模型进行描述。动态试验中,树脂柱在1 BV/h的流速下,对Cu^(2+)有较好的去除效果;在3种流速条件下,对黄连素的吸附率均较低,进一步验证了该型树脂对Cu^(2+)具有很好的选择吸附性。

关键词：树脂铜离子吸附热力学动力学黄连素废水

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The wide utility of rabbits as models of human diseases

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EXPERIMENTAL AND MOLECULAR MEDICINE 2018年第5期50卷 66-66页

作者： Esteves, Pedro J. Abrantes, Joana Baldauf, Hanna-Mari BenMohamed, Lbachir Chen, Yuxing Christensen, Neil Gonzalez-Gallego, Javier Giacani, Lorenzo Hu, Jiafen Kaplan, Gilla Keppler, Oliver T. Knight, Katherine L. Kong, Xiang-Peng Lanning, Dennis K. Le Pendu, Jacques de Matos, Ana Lemos liu, Jia liu, Shuying Lopes, Ana M. Lu, Shan Lukehart, Sheila Manabe, Yukari C. Neves, Fabiana McFadden, Grant Pan, Ruimin Peng, xuwen de Sousa-Pereira, Patricia Pinheiro, Ana Rahman, Masmudur Ruvoen-Clouet, Natalie Subbian, Selvakumar Tunon, Maria Jesus van der Loo, Wessel Vaine, Michael Via, Laura E. Wang, Shixia Mage, Rose Univ Porto CIBIO InBIO Res Network Biodivers & Evolutionary Biol Campus VairaoRua Padre Armando Quintas P-4485661 Vairao Portugal Univ Porto Dept Biol Fac Ciencias Rua Campo Alegre S-N P-4169007 Porto Portugal Inst Invest & Formacao Avancada Ciencias & Tecnol Gandra Portugal LMU Munchen Max von Pettenkofer Inst Fac Med Natl Reference Ctr Retroviruses D-81377 Munich Germany LMU Munchen Gene Ctr Fac Med VirolNatl Reference Ctr Retroviruses D-81377 Munich Germany Univ Calif Irvine Gavin Herbert Eye Inst Lab Cellular & Mol Immunol Sch Med Irvine CA 92697 USA Univ Calif Irvine Sch Med Dept Mol Biol & Biochem Irvine CA 92697 USA Univ Calif Irvine Inst Immunol Sch Med Sch Irvine Irvine CA 92697 USA Univ Massachusetts Med Sch Dept Med Worcester MA 01605 USA Penn State Univ Dept Pathol Hershey PA USA Penn State Univ Dept Microbiol & Immunol Hershey PA USA Penn State Univ Dept Comparat Med Hershey PA USA Univ Leon Inst Biomed IBIOMED Leon 24071 Spain Univ Leon CIBERehd Leon 24071 Spain Univ Washington Dept Med Seattle WA USA Univ Washington Dept Global Hlth Seattle WA 98195 USA Bill & Melinda Gates Fdn Seattle WA USA Loyola Univ Chicago Dept Microbiol & Immunol Maywood IL 60153 USA NYU Sch Med Dept Biochem & Mol Pharmacol New York NY 10016 USA Univ Nantes Univ Angers CRCINA INSERM Nantes France Arizona State Univ Biodesign Inst Ctr Immunotherapy Vaccines & Virotherapy Tempe AZ 85287 USA Univ Arkansas Med Sci Dept Microbiol & Immunol Little Rock AR 72205 USA Univ Porto Inst Biomed Sci Abel Salazar ICBAS Dept Anat Porto Portugal Univ Porto Inst Biomed Sci Abel Salazar ICBAS Unit Multidisciplinary Res Biomed UMIB Porto Portugal Johns Hopkins Univ Sch Med Dept Med Div Infect Dis Baltimore MD 21205 USA Rutgers State Univ PHRI New Jersey Med Sch RBHS Newark NJ USA NIAID Tubercolosis Res Sect Lab Clin Infect Dis Div Intramural ResNIH 9000 Rockville Pike Bethesda MD 20892 USA Univ Cape Town Dept Clin Lab Sci Inst Infect

Studies using the European rabbit Oryctolagus cuniculus contributed to elucidating numerous fundamental aspects of antibody structure and diversification mechanisms and continue to be valuable for the development and testing of therapeutic humanized polyclonal and monoclonal antibodies. Additionally, during the last two decades, the use of the European rabbit as an animal model has been increasingly extended to many human diseases. This review documents the continuing wide utility of the rabbit as a reliable disease model for development of therapeutics and vaccines and studies of the cellular and molecular mechanisms underlying many human diseases. Examples include syphilis, tuberculosis, HIV-AIDS, acute hepatic failure and diseases caused by noroviruses, ocular herpes, and papillomaviruses. The use of rabbits for vaccine development studies, which began with Louis Pasteur's rabies vaccine in 1881, continues today with targets that include the potentially blinding HSV-1 virus infection and HIV-AIDS. Additionally, two highly fatal viral diseases, rabbit hemorrhagic disease and myxomatosis, affect the European rabbit and provide unique models to understand co-evolution between a vertebrate host and viral pathogens.

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基于红外热像仪对珠状凝结换热过程实验

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空间科学学报 2016年第4期36卷 520-524页

作者：王许稳晏硕刘秋生朱志强中国科学院力学研究所北京100190

通过非接触式测温装置红外热像仪,观测冷凝液滴的形成、生长以及液滴之间汇聚、滚落过程.实验发现在珠状冷凝过程中,其表面温度变化显著.随着冷凝过程的进行,小液滴逐渐汇聚成大液滴,其液滴单位面积换热量明显下降,液滴表面温度逐渐降低... 详细信息

通过非接触式测温装置红外热像仪,观测冷凝液滴的形成、生长以及液滴之间汇聚、滚落过程.实验发现在珠状冷凝过程中,其表面温度变化显著.随着冷凝过程的进行,小液滴逐渐汇聚成大液滴,其液滴单位面积换热量明显下降,液滴表面温度逐渐降低.微纳米级小液滴在珠状冷凝换热中具有至关重要的作用.液滴在洁净表面上的珠状凝结和液滴在汇合后自清理表面上的珠状凝结表现出不同的温度分布,即珠状凝结汇聚后的自清理表面一直被前驱膜所覆盖.

关键词：珠状凝结红外图像热流量相变传热实验研究

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天舟一号空间冷凝实验装置地基冷凝实验

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空间科学学报 2016年第4期36卷 531-535页

作者：晏硕王许稳刘秋生朱志强中国科学院力学研究所北京100190

天舟一号(TZ-1)蒸发与冷凝实验装置地面科学匹配实验是优化空间实验参数与两相试验系统技术参数的重要环节.通过地面科学匹配冷凝实验,控制冷凝实验输入条件,观察条件变化给非稳态冷凝换热带来的影响,可为空间实验数据处理提供修正依据... 详细信息

天舟一号(TZ-1)蒸发与冷凝实验装置地面科学匹配实验是优化空间实验参数与两相试验系统技术参数的重要环节.通过地面科学匹配冷凝实验,控制冷凝实验输入条件,观察条件变化给非稳态冷凝换热带来的影响,可为空间实验数据处理提供修正依据.实验内容主要包括:改变冷凝台和蒸气温度,获得换热系数随时间变化的规律,从而指导空间实验数据采集和液池加热;通过实验验证蒸气压力对液膜换热系数的影响.实验还证明了冷凝台温度、蒸气温度、抽气压力等对换热系数也都有很大影响.地面科学匹配实验对于完善实验装置、优化工况与实验参数以及提高实验可靠性具有指导意义.

关键词：地面匹配两相流动冷凝实验换热系数

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二溴海因对吉富罗非鱼血浆抗氧化酶基因表达的影响

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环境科学与技术 2017年第2期40卷 39-43页

作者：郑尧邴旭文裘丽萍范立民宋超孟顺龙刘涛孙博李丹丹张聪陈家长中国水产科学研究院淡水渔业研究中心农业部淡水鱼类遗传育种与养殖生物学重点开放实验室农业部长江下游渔业资源环境科学观测实验站中国水产科学研究院内陆渔业生态环境和资源重点开放实验室江苏无锡214081 南京农业大学无锡渔业学院江苏无锡214081

研究不同时间点(1、2、4、8、16 d)及修复期(26 d)、不同浓度(0、0.06、0.3、1.5 mg/L)二溴海因(DBDMH)对雄性吉富罗非鱼血浆中抗氧化酶基因的基因毒性,筛选稳定的生物标志物。实时荧光定量PCR方法检测DBDMH对超氧化物歧化酶(sod)、谷... 详细信息

研究不同时间点(1、2、4、8、16 d)及修复期(26 d)、不同浓度(0、0.06、0.3、1.5 mg/L)二溴海因(DBDMH)对雄性吉富罗非鱼血浆中抗氧化酶基因的基因毒性,筛选稳定的生物标志物。实时荧光定量PCR方法检测DBDMH对超氧化物歧化酶(sod)、谷胱甘肽-S-转移酶(gst)、谷胱甘肽还原酶(gr)、谷胱甘肽过氧化物酶1(gpx1)、过氧化氢酶(cat)基因表达的影响。中浓度组雄性吉富罗非鱼血浆抗氧化酶基因(除gr)表达受DBDMH胁迫诱导显著上调;各DBDMH浓度组1 d(sod,gst,gpx1),2 d(gst,gr)抗氧化基因表达呈现浓度依赖性下降,4 d sod,gpx1基因表达呈现浓度依赖性上升;8 d中浓度DBDMH处理组基因表达(gst,gr,gpx1)显著低于低浓度组;恢复试验阶段,中、高浓度DBDMH组各抗氧化酶基因表达均不能恢复到正常水平。0.3 mg/L DBDMH显著增强雄性吉富罗非鱼血浆所测抗氧化酶基因的表达(除1 d gpx1、cat,8和16 d gr),此浓度下抗氧化酶基因作为标志物较合适。

关键词：吉富罗非鱼二溴海因血浆抗氧化酶基因

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