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Fabrication of piezoelectric AlN thin film for FBars

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Science China(Physics,Mechanics & Astronomy) 2009年第2期52卷 226-232页

作者： TAY Kok-Wan KUO Sin-cha WU Menq-Jion Department of Electrical Engineering Wu Feng Institute of Technology Department of Electronics Engineering Far East University Tainan 744 Department of Mechatronics Engineering National Changhua University of Education Changhua 500

This paper focuses on the fabrication of film bulk acoustic-wave resonator (FBar) comprising an aluminum nitride (AlN) piezoelectric thin film sandwiched between two metal electrodes and located on a silicon substrate with a low-stress silicon nitride (Si3N4) support membrane for high frequency wireless applications, and analyzes the optimization of the thin AlN film deposition parameters on Mo electrodes using the reactive rF magnetron sputter system. Several critical parameters of the sputtering process such as rF power and ar/N2 flow rate ratio were studied to clarify their effects on different electrodes characteristics of the AlN films. The experiment indicated that the process for Mo electrode was easier compared with that of the Pt/Ti or Au/Cr bi-layer electrode as it entailed only one photo resist and metal deposition step. Besides, Pt/Ti or Au/Cr electrodes reduced the resonance frequency due to their high mass density and low bulk acoustic velocity. Compared with the case of the Al bottom electrode, there is no evident amorphous layer between the Mo bottom electrode and the deposited AlN film. The characteristics of the FBar devices depend not only upon the thickness and quality of the AlN film, but also upon the thickness of the top electrode and the materials used. The results indicate that decreasing the thickness of either the AlN film or the top electrode increases the resonance frequency. This suggests the potential of tuning the performance of the FBar device by carefully controlling AlN film thickness. Besides, increasing either the thickness of the AlN film or higher rF power has improved a stronger c-axis orientation and tended to promote a narrower rocking curve full-width at half-maximum (FWHM), but increased both the grain size and the surface roughness. An FBar device fabricated under optimal AlN deposition parameters has demonstrated the effective electromechanical coupling coefficient (k eff 2 ) and the quality factor (Q f x ) are about 1.5

关键词： sputtering thin film piezoelectric

Augmented reality for realistic Simulation Using Improved Snake and Picking Algorithm by Proportional relational Expression

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International Journal of Communications, Network and System Sciences 2009年第7期2卷 687-694页

作者： JeongHee cha GyeYoung KIM HyungIl CHOI 不详

In realistic simulation of mobile Augmented reality, essential point is how to best depict occluded ar.a in such a way that the user can correctly infer the depth relationships between real and virtual objects. However, if the constructed 3D map of real world is not accurate or the density is not sufficient to estimate the object boundary, it is very difficult to determine the occluded ar.a. In order to solve this problem, this paper proposes a new method for calculating the occlusion ar.a using the improved snake algorithm and picking algo-rithm by the proportional relational expression. First, we generated the wireframe by the DEM in the experimental region and mapped to CCD real image using visual clues. And then, we calculated the 3D information at the point where occlusion problem for a moving virtual target by the proposed method. Experimental results show the validity of the proposed approach under the environment in which partial occlusions occur.

关键词： Snake Picking DEM Occlusion ar Simulation

发展中的贫困问题研究——基于云南少数民族地区案例分析

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云南民族大学学报（哲学社会科学版） 2012年第1期29卷 104-110页

作者：茶洪旺北京邮电大学经济管理学院北京100876

西部大开发战略实施以来,虽然西部少数民族地区经济发展取得了显著成效,但是发展中贫困问题依旧十分突出,与东部发达地区的差距仍在扩大。发展并不意味着就能消除贫困,如何消除发展中贫困问题,这是当前西部少数民族地区发展中面临的最... 详细信息

西部大开发战略实施以来,虽然西部少数民族地区经济发展取得了显著成效,但是发展中贫困问题依旧十分突出,与东部发达地区的差距仍在扩大。发展并不意味着就能消除贫困,如何消除发展中贫困问题,这是当前西部少数民族地区发展中面临的最大挑战。云南是我国少数民族自治地方最多的省份,又是我国民族自治地方陆路边境线最长的区域,少数民族问题与边境国际问题交织在一起,这在全国既有代表性,又有典型性。由于历史和现实原因,云南少数民族地区不仅是我国地缘政治上的重要战略门户,而且还是我国贫困人口比例最高、贫困程度最深的欠发达地区。"民族问题、边境问题、贫困问题"相互交融,构成了云南少数民族地区的主要问题。从生存贫困和发展贫困两方面深入分析云南少数民族地区发展中的贫困问题,可为消除发展中贫困问题献计献策。

关键词：发展中贫困生存贫困发展贫困差异化扶持政策

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不同化学反应机理对爆震波模拟的影响

燃烧科学与技术 2008年第4期14卷 355-360页

作者：熊姹严传俊邱华西北工业大学动力与能源学院西安710072

采用三阶TVD迎风格式和Strang-splitting算子分裂法以及H-O单步总反应和4种简化反应对爆震燃烧波进行了一维数值模拟,计算结果表明,这5种反应机理都成功起爆并且形成了爆震波.采用单步总反应方程得不到Von-Neumann压力平台区,虽然其Von-... 详细信息

采用三阶TVD迎风格式和Strang-splitting算子分裂法以及H-O单步总反应和4种简化反应对爆震燃烧波进行了一维数值模拟,计算结果表明,这5种反应机理都成功起爆并且形成了爆震波.采用单步总反应方程得不到Von-Neumann压力平台区,虽然其Von-Neumann压力峰值与C-J理论最为接近,但是其峰值温度以及爆震波速度过高.采用多步反应机理能很好地捕捉到ZND结构,其爆震波速度与峰值温度能很好地与C-J值一致,采用48反应得到的诱导区长度最小.用CHEMKIN软件计算各化学反应机理得到OH质量分数,采用34反应与CHEMKIN的结果误差最小.采用多步基元反应得到的结果比采用单步总反应所得的爆震波参数更为理想,OH原子团的质量分数可以作为评价化学反应机理是否准确的一个标准.

关键词：三阶TVD Strang-splitting算法化学反应机理爆震波

Gene transfer of a β_2-adrenergic receptor kinase inhibitor up-regulates the level of β_2-adrenergic receptor and cAMP in the asthmatic murine lung

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Journal of Nanjing Medical University 2005年第4期19卷 177-180页

作者： Mao Huang Yan Wu Xin Yao Wuangjian cha Kaisheng Yin Department of respiratory Medicine the First Affiliated Hospital of Nanjing Medical University Nanjing 210029 China

Objective： To investigate the effects of gene transfer of a β-adrenergic receptor（β-ar） kinase inhibitor（β arIct） on pulmonary β2-adrenergic receptor and cAMP following β2-ar.agonist treatment in asthmatic mice, and to analyze the relationship between the routes of gene delivery and the changes of β2ar.and cAMP. Methods： BALB/c mice were sensitized and challenged by ovalbumin to establish the asthmatic model treated with βar.agonist （salbutamol injected intramuscularly）. The plasmid with the expression of βarKct was constructed and βarKct gene transfer was performed through intravenous injection or intratracheal instillation in asthmatic mice. The gene expression was measured with Western blot analysis, and the changes of pulmonary β-ar.and cAMP evaluated by radioimmunoassay. results： The expression of tranfered βarKct gene was detectable in lungs and it was expressed more in the lungs of the mice receiving intratracheally plasmid than those receiving intravenously. The levels of βar.and cAMP were upregulated after using plasmid-βarKct to the asthmatic mice treated with βar.agonist. Conclusion： Our results indicated that there were down-regulation of βar.and cAMP in asthmatic mice treated with βar.agonist. Gene transfer of βarKct could inhibit the extent of the down-regulation of βar.and cAMP. The route of gene delivery could also affect the degree of up-regulation of βar.and cAMP. Gene transfer βarKct may provide a novel approach to the therapeutic strategy for asthma.

关键词： β-adrenergic receptor Asthma cAMP Genetransfer β-adrenergic receptor agonist

西昆仑-喀喇昆仑地区钾质碱性岩ar.ar年龄——以羊湖、昝坎和苦子干岩体为例

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矿物岩石 2006年第2期26卷 66-70页

作者：林清茶夏斌张玉泉中国科学院边缘海地质重点实验室中国科学院广州地球化学研究所

位于西藏西北部和新疆西南部中间地带的西昆仑-喀喇昆仑山地区的羊湖、昝坎和苦子干火山岩岩体是哀牢山-金沙江新生代钾质碱性岩浆岩带的西延部分,A r-A r测年结果为18 M a^12 M a,结合该地区岩体的岩石化学成分研究,表明哀牢山-金沙江... 详细信息

位于西藏西北部和新疆西南部中间地带的西昆仑-喀喇昆仑山地区的羊湖、昝坎和苦子干火山岩岩体是哀牢山-金沙江新生代钾质碱性岩浆岩带的西延部分,A r-A r测年结果为18 M a^12 M a,结合该地区岩体的岩石化学成分研究,表明哀牢山-金沙江新生代钾质碱性岩浆岩带的岩浆作用东早西晚,始于始新世中期(41 M a)到更新世(0.3 M a^0.07 M a),岩浆作用时间长达40 M a。这一现象与印度、欧亚两大陆碰撞时间在50 M a^45M a至今是一致的,暗示其成因与印度、欧亚两大陆碰撞有内在的联系。

关键词： ar.ar年龄钾质碱性岩羊湖昝坎苦子干西昆仑喀喇昆仑山地区

Micron-gap spacers with ultrahigh thermal resistance and mechanical robustness for direct energy conversion Samuel

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Microsystems & Nanoengineering 2019年第1期5卷 344-355页

作者： M.Nicaise Chen Lin Mohsen Azadi Tara Bozorg-Grayeli Promise Adebayo-Ige Drew E.Lilley Yann Pfitzer Wujoon cha Kyana Van Houten Nicholas A.Melosh roger T.Howe Jared W.Schwede Igor Bar.atin Mechanical Engineering and Applied Mechanics University of PennsylvaniaPhiladelphiaPA 19104USA Materials Science&Engineering Stanford UniversityStanford 94305 CAUSA Chemical and Biomolecular Engineering University of PennsylvaniaPhiladelphiaPAUSA Spark Thermionics BerkeleyCA 94720USA Electrical Engineering Stanford UniversityStanfordCA 94305USA

In thermionic energy converters,the absolute efficiency can be increased up to 40%if space-charge losses are eliminated by using a sub-10-μm gap between the *** practical way to achieve such small gaps over large device ar.as is to use a stiff and thermally insulating spacer between the two *** report on the design,fabrication and characterization of thin-film alumina-based spacers that provided robust 3–8μm gaps between planar substrates and had effective thermal conductivities less than those of *** spacers were fabricated on silicon molds and,after release,could be manually transferred onto any *** large-scale compression testing,they sustained compressive stresses of 0.4–4 MPa without ***,the thermal conductance was 10–30 mWcm^(−2)K^(−1)and,surprisingly,independent of film thickness(100–800 nm)and spacer *** explain this independence,we developed a model that includes the pressure-dependent conductance of locally distributed asperities and sparse contact points throughout the spacer structure,indicating that only 0.1–0.5%of the spacerelectrode interface was conducting *** spacers show remar.able functionality over multiple length scales,providing insulating micrometer gaps over centimeter ar.as using nanoscale *** innovations can be applied to other technologies requiring high thermal resistance in small spaces,such as thermophotovoltaic converters,insulation for spacecraft and cryogenic devices.

关键词： thermal resistance film

自噬抑制剂促进缺氧诱导的大鼠乳鼠心肌细胞凋亡

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基础医学与临床 2014年第2期34卷 185-189页

作者：王路乔黄波黄茶花王伶程晓曙南昌大学第二附属医院心血管内科江西南昌330006 南昌大学第二附属医院检验科江西南昌330006

目的探讨抑制自噬后对大鼠乳鼠心肌细胞缺氧诱导的促凋亡蛋白Bim、caspase-3表达的影响及低氧诱导因子1(HIF-1)的调控作用。方法体外培养1～3 d龄SD大鼠心肌细胞建立缺氧模型,检测缺氧0、2、4、8、14和24 h时自噬情况,取自噬显著升高的... 详细信息

目的探讨抑制自噬后对大鼠乳鼠心肌细胞缺氧诱导的促凋亡蛋白Bim、caspase-3表达的影响及低氧诱导因子1(HIF-1)的调控作用。方法体外培养1～3 d龄SD大鼠心肌细胞建立缺氧模型,检测缺氧0、2、4、8、14和24 h时自噬情况,取自噬显著升高的时间点细胞作为单纯缺氧组(anoxia组),缺氧前用10 mmol/L3-甲基腺嘌呤(3MA)预处理心肌细胞1h作为缺氧+3-甲基腺嘌呤组(anoxia+3MA组),设立正常对照组(control组)。倒置显微镜下观察各组心肌细胞的搏动频率和异常节律;全自动血液生化分析仪检测乳酸脱氢酶LDH的活性;Western blot检测各组中LC3-Ⅱ/Ⅰ、Bim、caspase-3和HIF-1蛋白表达情况。结果抑制自噬后心肌细胞搏动频率明显减弱并可见异常节律、LDH释放增加(P<0.05),同时Bim和caspase-3表达明显升高(P<0.05);缺氧+3MA组中HIF-1蛋白表达明显低于单纯缺氧组(P<0.05)。结论自噬抑制剂抑制自噬后导致缺氧诱导的大鼠乳鼠心肌细胞凋亡增加,HIF-1正调控缺氧诱导的自噬抵抗凋亡发挥心肌保护作用。

关键词：自噬缺氧 Bim caspase-3 HIF-1

GUTOr UPS系统关机后无法切旁路的解决方案

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中国核电 2022年第3期15卷 353-357页

作者：曹祖庭查卫华中核核电运行管理有限公司浙江海盐314300

GUTOrUPS广泛应用于核电站核岛和常规岛重要的负荷,该品牌在中国核电核级UPS的市场占有率在90%以上。不过近几年来在国内一些核电机组中发生了多起由于UPS无征兆关机(死机)导致负荷失电的事件。UPS关机(死机)无法切换到旁路运行已经影... 详细信息

GUTOrUPS广泛应用于核电站核岛和常规岛重要的负荷,该品牌在中国核电核级UPS的市场占有率在90%以上。不过近几年来在国内一些核电机组中发生了多起由于UPS无征兆关机(死机)导致负荷失电的事件。UPS关机(死机)无法切换到旁路运行已经影响到了核电的安全可靠运行。本文从硬件原理和逻辑上分析了无法切换的原因,提出了一种强制静态旁路的方案,通过该方案能够解决极端情况下负荷失电的缺陷,提高了UPS设备的可靠性。

关键词： GUTOr UPS 核电强制静态旁路