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National Science Review 2017年第2期4卷 196-209页

作者： Ying Yu Guo-Wei Zha Xiang-Jun Shang Shuang yang ban-quan Sun Hai-Qiao Ni Zhi-Chuan Niu State Key laboratory for Superlattice and Microstructures Institute of SemiconductorsChinese Academy of Sciences State Key Laboratory of Optoelectronic Materials and Technologies School of electronics and information technologySun Yat-sen University College of Materials Science and Opto-Electronic Technology University of Chinese Academy of Sciences Synergetic Innovation Center of quantum Information& quantum Physics University of Science and Technology of China

In this chapter, we discuss the epitaxial growth of self-assembled quantum dots(QDs) in GaAs nanowires(NWs) and the characteristics of their single-photon emissions. We demonstrate Ga droplet-induced gold-free vapor-liquid-solid growth of hexagonal GaAs/Al GaAs core–shell NWs, branched GaAs NWs and tailored nanostructured morphologies on the NW facets. Particularly, we show two new types of QD-in-NW systems: one is a single InAs QD formed at the corner of a branched GaAs NW, and the other is a single GaAs QD formed on the NW facet. Sharp excitonic emission spectral lines are observed with vanishing two-photon emission probability. Furthermore, a single GaAs QD is achieved at the site of a single Al GaAs quantum ring(QR) on the NW facet. In addition, these NW-based single QDs are in-situ probed and integrated with single-mode optical ibers to achieve all-iber-output single-photon sources for potential application in quantum integrated networks.

关键词： self-assembled nanowires quantum dots single photon emitters molecular beam epitaxy

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涂层断裂韧性的声发射辅助拉伸测量方法

兵工学报 2008年第4期29卷 420-424页

作者：杨班权张坤陈光南罗耕星肖京华中国科学院力学研究所

涂层的断裂韧性与界面结合强度是表征涂层/基体材料体系力学性能的重要指标。但如何准确地测量涂层的断裂韧性和强界面结合的涂层/基体材料体系的界面结合强度至今仍存在困难。以铬涂层/钢基体材料为对象,采用声发射和显微镜实时动态检... 详细信息

涂层的断裂韧性与界面结合强度是表征涂层/基体材料体系力学性能的重要指标。但如何准确地测量涂层的断裂韧性和强界面结合的涂层/基体材料体系的界面结合强度至今仍存在困难。以铬涂层/钢基体材料为对象,采用声发射和显微镜实时动态检测技术与拉伸实验相结合的方法,探索了铬涂层的断裂韧性以及铬涂层/钢基体的界面剪切强度。根据相关力学模型和实验测量结果,得到铬涂层在室温下的断裂韧性为27.41 J/m2.同时,发现在铬涂层裂纹饱和后界面开裂都未发生,获得了该种材料体系界面剪切强度的一个下限值。

关键词：材料检测与分析技术断裂韧性界面剪切强度拉伸实验声发射铬涂层钢基体材料

磁控溅射ZrAlCuN薄膜的微观组织与力学性能

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中国表面工程 2014年第5期27卷 109-114页

作者：杜军杨班权孟凡军装甲兵工程学院再制造技术国家重点实验室北京100072 装甲兵工程学院机械工程系北京100072

采用磁控溅射技术制备不同原子比的ZrAlCuN薄膜。采用场发射扫描电镜（FESEM）观察截面形貌,高分辨透射电镜分析微观组织结构,纳米压入法测定薄膜的硬度,压入法（维氏压头）测定薄膜的韧性。结果表明：Zr0.36Al0.15Cu0.01N0.48薄膜截面... 详细信息

采用磁控溅射技术制备不同原子比的ZrAlCuN薄膜。采用场发射扫描电镜（FESEM）观察截面形貌,高分辨透射电镜分析微观组织结构,纳米压入法测定薄膜的硬度,压入法（维氏压头）测定薄膜的韧性。结果表明：Zr0.36Al0.15Cu0.01N0.48薄膜截面呈纳米尺度柱状晶,沿沉积方向生长,仅存在[111]、[200]、[220]、[311]取向的5-10nm ZrN晶粒,未发现AlN及Cu独立相,硬度约41.7GPa（载荷10mN）,弹性模量约257.8GPa。Zr0.29Al0.24Cu0.08N0.39薄膜呈纳米尺度柱状晶,存在10-20nm ZrN纳米晶以及Cu[111]纳米晶,硬度约27GPa（载荷10mN）,弹性模量约225.8GPa。由于前者具备较高的硬度/弹性模量比,从而表现出较好的韧性。

关键词：磁控溅射薄膜硬度韧性微观组织

Chinese physicians' perceptions of fecal microbiota transplantation

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World Journal of Gastroenterology 2016年第19期22卷 4757-4765页

作者： Rong-Rong Ren Gang Sun Yun-Sheng yang Li-Hua Peng Shu-Fang Wang Xiao-Hong Shi Jing-quan Zhao Yong-Ling ban Fei Pan Xue-Hong Wang Wei Lu Jian-Lin Ren Ying Song Jiang-Bin Wang Qi-Ming Lu Wen-Yuan Bai Xiao-Ping Wu Zi-Kai Wang Xiao-Mei Zhang Ye Chen Institute of Digestive Diseases Chinese PLA General Hospital Chinese PLA Medical Academy Medical College of Nankai University Department of Traditional Chinese Medicine The First People’s Hospital of Hangzhou City Department of Respiratory The People’s Hospital of Dongying City Department of Gastroenterology Affiliated Hospital of Qinghai University Department of Gastroenterology First Central Hospital of Tianjin Department of Gastroenterology Affiliated Hospital of Xiamen University Department of Gastroenterology Xi’an Central Hospital Department of Gastroenterology China-Japan Union of Jilin University Department of Gastroenterology the People’s Hospital of Gansu Department of Gastroenterology the Second Hospital of Hebei Medical University Department of Gastroenterology the Second Xiangya Hospital of Central South University Department of Gastroenterology Nanfang Hospital Southern Medical University

AIM: To explore Chinese physicians' perceptions towards fecal microbiota transplantation(FMT) and to provide information and an assessment of FMT development in ***: A self-administered questionnaire was developed according to the FMT practice guidelines and was distributed to physicians in hospitals via Internet Research Electronic Data Capture(REDcap) software and electronic mails to assess their attitudes toward and knowledge of FMT. The questionnaire included a brief introduction of FMT that was followed by 20 questions. The participants were required to respond voluntarily, under the condition of anonymity and without compensation. Except for the fill-in-the-blank questions, all of the other questions were required in the REDcap data collection systems, and the emailed questionnaires were completed based on ***: Up to December 9, 2014, 844 eligible questionnaires were received out of the 980 distributed questionnaires, with a response rate of 86.1%. Among the participants, 87.3% were from tertiary hospitals, and there were 647(76.7%) gastroenterologists and 197(23.3%) physicians in other departments(nongastroenterologists). Gastroenterologists' awareness of FMT prior to the survey was much higher than non-gastroenterologists'(54.3 vs 16.5%, P < 0.001); however, acceptance of FMT was not statistically different(92.4 vs 87.1%, P = 0.1603). Major concerns of FMT included the following: acceptability to patients(79.2%), absence of guidelines(56.9%), and administration and ethics(46.5%). On the basis of understanding, the FMT indications preferred byphysicians were recurrent Clostridium difficile infection(86.7%), inflammatory bowel disease combined with Clostridium difficile infection(78.6%), refractory ulcerative colitis(70.9%), ulcerative colitis(65.4%), Crohn's disease(59.4%), chronic constipation(43.7%), irritable bowel syndrome(39.1%), obesity(28.1%) and type 2 diabetes(23.9%). For donor selection, the majority of physicians preferred

关键词： Fecal microbiota transplantation Chinese physicians Gastroenterologists Perception Survey

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可控电抗器在我国超/特高压电网中的应用

中国电机工程学报 2007年第7期27卷 1-6页

作者：周勤勇郭强卜广全班连庚中国电力科学研究院北京市海淀区100085

特高压线路充电大,限制过电压和无功补偿矛盾突出,通过对特高压线路特性和典型系统分析可知,为解决这一矛盾,需要在长距离重载线路及潮流变化大的外送线路上安装特高压可控电抗器。特高压线路采用可控电抗器需要在500kV线路上挂网试验运... 详细信息

特高压线路充电大,限制过电压和无功补偿矛盾突出,通过对特高压线路特性和典型系统分析可知,为解决这一矛盾,需要在长距离重载线路及潮流变化大的外送线路上安装特高压可控电抗器。特高压线路采用可控电抗器需要在500kV线路上挂网试验运行,以解决可控电抗器在我国电网应用中的相关技术问题。研究表明:可控电抗器对系统暂态稳定的影响主要依赖于它在工况下的状态,而与其调节方式关系不大;而可控电抗器对系统动态稳定的影响则不仅与其工况下的状态相关,更主要的是与可控电抗器的调节方式相关,其中,无滞后环节平滑调节电抗器和多次动作分级投切电抗器在工况满负荷的情况下对系统具有最好的作用。

关键词：特高压无功补偿可控电抗器

基于加性间距胶囊网络的家庭活动识别方法研究

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电子学报 2020年第8期48卷 1580-1586页

作者：郑启航王章权刘半藤陈阳陈友荣常州大学信息科学与工程学院江苏常州213164 浙江树人大学信息科技学院浙江杭州310015

本文研究基于音频的家庭活动识别方法,提出了一种基于加性间距胶囊神经网络识别模型,针对传统胶囊神经网络目标函数仅以输出胶囊模长作为约束的弊端,本文以几何学的视角,在胶囊神经网络结构中加入Transition层,使用Transition层对胶囊... 详细信息

本文研究基于音频的家庭活动识别方法,提出了一种基于加性间距胶囊神经网络识别模型,针对传统胶囊神经网络目标函数仅以输出胶囊模长作为约束的弊端,本文以几何学的视角,在胶囊神经网络结构中加入Transition层,使用Transition层对胶囊单元空间关系进行变基至一维空间,再使用加性间距Softmax作为目标函数,以同类特征变化小,非同类特征差异大作为优化策略构建基于胶囊向量空间关系的目标函数以提高模型分类能力,最后对方法进行试验,采用音频事件对家庭活动进行分类识别.选择声学场景和事件检测与分类(Detection and Classification of Acoustic Scenes and Events,DCASE)2018挑战任务5作为数据集,进行分类器构建和测试,最终平均F1分数达到92.3%,优于其他主流方法.

关键词：音频事件分类家庭活动识别胶囊网络加性间距

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残余应力作用下脆性膜/基材料的断裂行为

装甲兵工程学院学报 2011年第1期25卷 88-91页

作者：杨班权李朋装甲兵工程学院机械工程系

假定膜内的残余拉应力足以使膜发生开裂,利用膜/基材料中含弹性界面层的剪滞模型,研究了脆性膜/基材料在残余应力作用下的开裂行为特征,探讨了膜内正应力、膜/基界面切应力的分布规律,获得了膜的裂纹密度与残余应力大小之间的解析表达... 详细信息

假定膜内的残余拉应力足以使膜发生开裂,利用膜/基材料中含弹性界面层的剪滞模型,研究了脆性膜/基材料在残余应力作用下的开裂行为特征,探讨了膜内正应力、膜/基界面切应力的分布规律,获得了膜的裂纹密度与残余应力大小之间的解析表达式。在裂纹密度、材料的力学和几何参数确定的情况下,该解析表达式可以用来评估残余应力的大小。最后,分析了膜的裂纹密度与残余应力、膜的厚度、弹性模量、断裂强度以及界面层的切变模量之间的内在关联,绘出了这些参数影响膜裂纹密度的变化曲线。

关键词：脆性膜/基材料残余应力裂纹密度