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超短脉冲激光诱导周期性表面结构（英文）

中国光学 2018年第1期11卷 1-17页

作者：李晨 stoian razvan 程光华法国里昂大学让莫内大学法国国家科学研究中心休伯特居里实验室法国圣埃蒂安市42000 中国科学院西安光学精密机械研究所瞬态光学与光子技术国家重点实验室陕西西安710119 陕西科技大学机电工程学院陕西西安710012

激光诱导周期性表面结构(Laser-induced periodic surface structures,LIPSS)具有纳米尺度的特征结构和自重复的微观尺度的排列图案,因此,LIPSS在传感器、太阳能发电、光催化等方面具有广泛的应用前景。本文首先介绍LIPSS形成过程中超... 详细信息

激光诱导周期性表面结构(Laser-induced periodic surface structures,LIPSS)具有纳米尺度的特征结构和自重复的微观尺度的排列图案,因此,LIPSS在传感器、太阳能发电、光催化等方面具有广泛的应用前景。本文首先介绍LIPSS形成过程中超快激光与物质相互作用的复杂过程,强调瞬态光学性质和表面结构变化的作用。然后综述几种具有代表性的LIPSS形成机理,并且讨论了各自的优缺点。接着介绍了LIPSS形成过程中材料的变化,主要包括材料化学成分、晶体结构和表面微观结构的变化。最后综述了LIPSS在材料表面处理、光学和机械等方面的应用。

关键词：超快光学飞秒激光微加工周期性表面结构

Ultrashort Bessel beam photoinscription of Bragg grating waveguides and their application as temperature sensors

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Photonics Research 2019年第7期7卷 121-129页

作者： Guodong Zhang Guanghua Cheng Manoj K.Bhuyan Ciro D'Amico Yishan Wang razvan stoian Laboratoire Hubert Curien UMR 5516 CNRSUniversite de LyonUniversite Jean Monnet42000 Saint EtienneFrance State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision MechanicsCASXi'an 710119China School of Electronics and Information Northwestern Polytechnical UniversityXi'an 710072China Academy of Scientific and Innovative Research CSIR-Central Scientific Instruments OrganizationChandigarh 160030India Optical Devices and Systems Division CSIR-Central Scientific Instruments OrganizationChandigarh 160030India

Ultrashort pulsed Bessel beams with intrinsic nondiffractive character and potential strong excitation confinement down to 100nm can show a series of advantages over Gaussian beams in fabricating efficient Bragg grating waveguides(BGWs).In this work, we focus on parameter management for the inscription of efficient BGWs using the point-by-point method employing Bessel *** to their high aspect ratio, the resulting one-dimensional void-like structures can section the waveguides and interact efficiently with the optical modes. Effective first-order BGWs with low birefringence can then be fabricated in bulk fused silica. By controlling the size and the relative location of grating voids via the Bessel pulse energy and scan velocities, the resonant behaviors of BGWs can be well regulated.A high value of 34 dB for 8 mm length is achieved.A simple predictive model for BGWs is proposed for analyzing the influences of processing parameters on the performance of BGWs. The technique permits multiplexing several gratings in the same *** to eight grating traces were straightforwarcliy inscribed into the waveguide in a parallel-serial combined mode, forming the multiplex *** an application, the multiplex BGW sensor with two resonant peaks is proposed and fabricated for improving the reliability of temperature detection.

关键词： photoinscription waveguides temperature detection

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飞秒激光光刻波导偏振器

光子学报 2011年第6期40卷 818-822页

作者：林灵杨小君白晶龙学文吕百达 razvan stoian 惠荣庆程光华四川大学激光物理与化学研究所成都610064 中国科学院西安光学精密机械研究所瞬态光学与光子技术国家重点实验室西安710119 Laboratoire Hubert Curien UMR5516 CNRS Universit'e de Lyon Universit'e Jean Monnet Depart ment of Electrical Engineering and Computer Science The University of Kansas

飞秒激光诱导折射率变化提供了一种灵活的三维光子器件制作手段.飞秒激光光刻的II类波导具有偏振导光特性,可以作为波导偏振器,但是对于要保留的偏振分量损耗太大.本文阐述了一种利用飞秒激光在熔融石英中制作的新型低损耗波导偏振器.... 详细信息

飞秒激光诱导折射率变化提供了一种灵活的三维光子器件制作手段.飞秒激光光刻的II类波导具有偏振导光特性,可以作为波导偏振器,但是对于要保留的偏振分量损耗太大.本文阐述了一种利用飞秒激光在熔融石英中制作的新型低损耗波导偏振器.它由中间的一根I类波导及两侧的两根II类纳米光栅轨迹构成.基于飞秒激光诱导的纳米光栅的偏振依赖散射特性,II类纳米光栅轨迹能够对I类波导的倏逝场进行调制.偏振方向垂直于纳米光栅的模式相对于偏振方向平行于纳米光栅的模式有更大的散射损耗,因此导通的是偏振方向平行于纳米光栅的模式.研究了消光比随I类波导与II类纳米光栅轨迹之间的间距的变化关系,选择一个最佳间距来进一步研究消光比随II类纳米光栅轨迹长度的变化关系.在间距6μm,II类纳米光栅轨迹扫描长度6 mm处实现了最大15.91 dB的消光比.通过增加II类轨迹的长度或者数量,很容易得到更高的消光比.

关键词：飞秒激光光刻波导偏振器

Evaluation of the effective thermal conductivity of composite polymers by considering the filler size distribution law

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第5期10卷 704-709页

作者： Sorin HOLOTESCU Floriana D. stoian Department of Thermal Machines Technology and Transportation "Politehnica" University of TimisoaraTimisoara RO-300222 Romania

We present an empirical model for the effective thermal conductivity (ETC) of a polymer composite that includes dependency on the filler size distribution-chosen as the Rosin-Rammler distribution. The ETC is determined based on certain hypotheses that connect the behavior of a real composite material A, to that of a model composite material B, filled with mono-dimensional filler. The application of these hypotheses to the Maxwell model for ETC is presented. The validation of the new model and its characteristic equation was carried out using experimental data from the reference. The comparison showed that by using the size distribution law a very good fit between the equation of the new model (the size distribution model for the ETC) and the reference experimental results is obtained, even for high volume fractions, up to about 50%.

关键词： Effective thermal conductivity (ETC) Filler size distribution Equivalent volume fraction Composite polymer

Excitation and relaxation dynamics in ultrafast laser irradiated optical glasses

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High Power Laser Science and Engineering 2016年第4期4卷 1-8页

作者： C.Mauclair A.Mermillod-Blondin K.Mishchik J.Bonse A.Rosenfeld J.P.Colombier R.stoian Laboratoire Hubert Curien UMR 5516 CNRSUniversité de LyonUniversité Jean Monnet Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie Bundesanstalt für Materialforschung und-prüfung (BAM)

We discuss the dynamics of ultrashort pulsed laser excitation in bulk optical silica-based glasses(fused silica and borosilicate BK7) well-above the permanent modification threshold. We indicate subsequent structural and thermomechanical energy relaxation paths that translate into positive and negative refractive index changes, compression and rarefaction zones. If fast electronic decay occurs at low excitation levels in fused silica via self-trapping of excitons,for carrier densities in the vicinity of the critical value at the incident wavelength, persistent long-living absorptive states indicate the achievement of low viscosity matter states manifesting pressure relaxation, rarefaction, void opening and compaction in the neighboring domains. An intermediate ps-long excited carrier dynamics is observed for BK7 in the range corresponding to structural expansion and rarefaction. The amount of excitation and the strength of the subsequent hydrodynamic evolution is critically dependent on the pulse time envelope, indicative of potential optimization schemes.

关键词： carrier plasmas glasses pulse shaping refractive index engineering ultrafast laser excitation

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翻译与电影:俚语、方言、口音和多语言

电影评介 2022年第10期 29-32页

作者： Andreea Ema stoian 北京电影学院导演系

一、默片时代的字幕翻译与影像本体性.电影在诞生之初,被认为是影响力巨大的人类交流方式。这在默片时代是正确的,因为在引入插卡字幕之前,电影似乎没有必要进行翻译。被拍摄下来的影像可能包含着明显的文化符号,因此对原文化以外的观... 详细信息

一、默片时代的字幕翻译与影像本体性.电影在诞生之初,被认为是影响力巨大的人类交流方式。这在默片时代是正确的,因为在引入插卡字幕之前,电影似乎没有必要进行翻译。被拍摄下来的影像可能包含着明显的文化符号,因此对原文化以外的观众来说有些陌生;但是,这些记号的含义是可以被吸收的,就像吸收一幅画。在没有语言干扰的情况下,外国电影的观众有可能仅仅根据外表来识别人物。

关键词：外国电影影像本体文化符号默片一幅画字幕翻译人类交流

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The Efficiency of Non-repayable Funding Against Crisis Effects in Romania

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Journal of Modern Accounting and Auditing 2011年第10期7卷 1106-1115页

作者： George Daniel stoian Ioana Alina Negotei The Bucharest Academy of Economic Studies Romania

The current economical crisis pointed out the gaps and the weak development of the Romanian economical system. If we were to compare the economy of a country to the human body then we would realize that constant and massive loss of ＂blood＂ may eventually lead to collapse of the economical system, which require Romania to speed up financial ＂transfusions＂. In these conditions, the most accessible and inexpensive source of funding is the non-repayable funding that Romanian economy can acquire by the year of 2013. In this paper we analyze the evolution of non-repayable funds allocated to Romania, in terms of those funds for the approved projects （their implementation has not yet started） but also in terms of those contracted projects or in the process of running （in fact representing ＂the necessary＂ amount of money that the Romanian economy needs）. The first part of the paper contains an overview of the situation about the requiring and the absorption of non-repayable funding since 2007 （officially since the crisis emerged in the U.S.） to present, also making an analysis of the influence they had on the Romanian economy. We take into account in this analysis that the effects of the crisis in Romania began to be felt in the second half of 2008, economical politics against crisis were not taken into accounted by this date. In this analysis we started from the assumption that one anti-crisis policy, taken into account by public decision members in Romania, is to increase efficiency and absorption of funds by raising the capacity of the Romanian economical environment for the implementation （and not only the winning ） of these funds. The second part of the paper contains an econometrieal development model which highlights the influence of changing the interest rates and exchange rate on the rate of contracting projects during January 2007-March 2010. The Analysis of the results emphasizes the stronger influence of the changing rate on the approved contracting projects comp

关键词： non-repayable funds economic and financial crisis economic recovery contraction rate approved projects

费穆:中国宝贵的电影遗产——家国情怀与电影美学

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电影评介 2020年第16期 16-19页

作者： [罗马尼亚]Andreea Ema stoian 北京电影学院导演系

托尔斯泰如此定义艺术,同时也描述了它的特性:"艺术是一种人类活动,它存在于此,一个人有意识地依靠特定的外部符号,向他人传达他曾经历过的感受,他认为其所受到感染并同样经历了这些感受。"[1]对费穆来说,艺术的价值,就在于这是一种将... 详细信息

托尔斯泰如此定义艺术,同时也描述了它的特性:"艺术是一种人类活动,它存在于此,一个人有意识地依靠特定的外部符号,向他人传达他曾经历过的感受,他认为其所受到感染并同样经历了这些感受。"[1]对费穆来说,艺术的价值,就在于这是一种将自身情感传递的价值。

关键词：电影美学费穆情感传递家国情怀托尔斯泰价值经历

Narrow-band imaging with magnifying endoscopy for the evaluation of gastrointestinal lesions

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World Journal of Gastrointestinal Endoscopy 2015年第2期7卷 110-120页

作者： Alina Boeriu Cristian Boeriu Silvia Drasovean Ofelia Pascarenco Simona Mocan Mircea stoian Daniela Dobru Department of Gastroenterology University of Medicine and Pharmacy Tirgu Mures University of Medicine and Pharmacy Tirgu Mures Tirgu Mures County Emergency Hospital Department of Pathology Tirgu Mures County Emergency Hospital Department of Anesthesia and Intensive Care Mures County Hospital

Narrow band imaging(NBI) endoscopy is an optical image enhancing technology that allows a detailed inspection of vascular and mucosal patterns, providing the ability to predict histology during real-time endoscopy. By combining NBI with magnification endoscopy(NBI-ME), the accurate assessment of lesions in the gastrointestinal tract can be achieved, as well as the early detection of neoplasia by emphasizing neovascularization. Promising results of the method in the diagnosis of premalignant and malignant lesions of gastrointestinal tract have been reported in clinical studies. The usefulness of NBI-ME as an adjunct to endoscopic therapy in clinical practice, the potential to improve diagnostic accuracy, surveillance strategies and cost-saving strategies based on this method are summarized in this review. Various classification systems of mucosal and vascular patterns used to differentiate preneoplastic and neoplastic lesions have been reviewed. We concluded that the clinical applicability of NBI-ME has increased, but standardization of endoscopic criteria and classification systems, validation in randomized multicenter trials and training programs to improve the diagnostic performance are all needed before the widespread acceptance of the method in routine practice. However, published data regarding the usefulness of NBI endoscopy are relevant in order to recommend the method as a reliable tool in diagnostic and therapy, even for less experienced endoscopists.

关键词： Narrow band imaging magnifying endoscopy Premalignant Early cancer Mucosal patterns Vascularpatterns