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Bonding quality of Yb:Y_3Al_5O_(12)/Y_3Al_5O_(12) composite crystals

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Science china(Technological Sciences) 2008年第9期51卷 1457-1463页

作者： Bourdet GILBET J c.chanteloup Ecole Polytechnique Laboratoire pour l'Utilisation des Lasers IntensesRoute de Saclay Palaiseau 91128 France

The Yb:Y3Al5O12/Y3Al5O12 (Yb:YAG/YAG) composite crystals were prepared by thermal bonding method with different technological parameters. The bonding in-terface of the composite crystals were observed by optical microscope, scanning electron microscope, and atom force microscope. The light scattering experiments for bonding interface of the composite crystals were measured by the laser and transmission spectra. All experiments show that high-quality Yb:YAG/YAG com-posite crystals without space transition layer and light scattering on the bonding interface can be obtained by thermal bonding method under appropriate technological parameters.

关键词： Yb:YAG/YAG bonding quality light scattering transmission spectra

Defining the optimal gradient doped Yb^(3+):YAG disk for room and low temperature diode pumped solid-state laser operations

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High Power Laser Science and Engineering 2014年第4期2卷 52-57页

作者： J.-c.chanteloup M.Arzakantsyan S.Marrazzo LULI Ecole Polytechnique CNRS CEA UPMCRoute de Saclay 91128 Palaiseau France

We propose a general methodology to define the optimum doping ion volume distribution required for an efficient solid-state laser amplifier. This approach is illustrated in the context of two experimental diode pumped Yb:YAG amplifiers operating at 300 and 160 K. Processing of such tailored gain media is now possible through horizontal direct crystallization.

关键词： diode solid-state laser laser gain medium doping engineering laser materials ytterbium YAG laser

热键合制作Yb：Y3Al5O12／Y3Al5O12复合晶体

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无机材料学报 2008年第1期23卷 125-129页

作者：王晓丹赵志伟王静雅徐军 Gilbert Bourdet J．-c.chanteloup 中国科学院上海光学精密机械研究所上海201800 中国科学院研究生院北京100049 Ecole Polytechnique Laboratoire pour l＇Utilisation des Lasers Intenses Route de Saclay Palaiseau 91128 France

采用热键合技术制备了Yb:Y_3Al_5O_(12)/Y_3Al_5O_(12)(Yb:YAG/YAG)复合晶体,对复合晶体进行了结构表征和键合质量检测.利用光学显微镜和扫描电镜观察了复合晶体横截面的形貌;在偏光显微镜下观察键合区域的应力,利用干涉条纹来表征复合... 详细信息

采用热键合技术制备了Yb:Y_3Al_5O_(12)/Y_3Al_5O_(12)(Yb:YAG/YAG)复合晶体,对复合晶体进行了结构表征和键合质量检测.利用光学显微镜和扫描电镜观察了复合晶体横截面的形貌;在偏光显微镜下观察键合区域的应力,利用干涉条纹来表征复合晶体的光学均匀性;通过红外透过光谱的测量来检测复合晶体的键合质量.实验结果表明:热键合技术制备的Yb:YAG/YAG复合晶体键合界面处无界面缺陷,不存在复合界面空间过渡层,光学均匀性良好.

关键词： Yb:YAG/YAG 键合质量应力光学均匀性热键合

Status and prospects for symmetric organic redox flow batteries

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Journal of Energy chemistry 2025年第1期100卷 125-143页

作者： Md Al Raihan c.Adam Dyker Department of chemistry University of New Brunswick

As environmental concerns from fossil fuel consumption intensify, large-scale energy storage becomes imperative for the integration of renewable sources like wind, hydro, and solar with the electrical *** flow batteries, particularly those employing organic molecules, are positioned as a key technology for this purpose. This review explores the growing field of symmetric organic redox flow batteries(ORFBs) within this context. Unlike traditional asymmetric designs based on unique active materials for each electrode, symmetric ORFBs involve a single bipolar species for both electrodes. This review highlights the benefits of a symmetric design, and categorizes five distinct classes of organic bipolar molecules used in both aqueous and non-aqueous solvents. By providing a comprehensive overview of their cell cycling and performance characteristics, the strengths and weaknesses of the diverse categories of bipolar molecules are highlighted for both solvent systems, as are opportunities for future development. This should guide new research directions and advance the development of practical symmetric ORFBs.

关键词： Redox flow battery Symmetric battery Organic battery Aqueous electrolyte Non-aqueous electrolyte

Yb掺杂原子数分数为0.5%的Yb∶Y_3Al_5O_(12)晶体的光谱分析

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中国激光 2006年第5期33卷 692-696页

作者：王晓丹赵志伟徐晓东宋平新姜本学徐军邓佩珍 Gilbert Bourdet J.-c.chanteloup 中国科学院上海光学精密机械研究所 Ecole Polytechnique Laboratoire pour l'Utilisation des Lasers IntensesPalaiseau 91128France Ecole Polytechnique Laboratoire pour l’Utilisation des Lasers IntensesPalaiseau 91128France

采用提拉法生长了Yb掺杂原子数分数为0.5%的Yb∶Y3Al5O12(Yb∶YAG)晶体,对晶体的吸收光谱和荧光光谱进行了分析。与Yb掺杂原子数分数为5%的Yb∶YAG晶体进行了对比,得出采用940 nm激光二极管(LD)抽运晶体最为合适。原子数分数为0.5%的Yb... 详细信息

采用提拉法生长了Yb掺杂原子数分数为0.5%的Yb∶Y3Al5O12(Yb∶YAG)晶体,对晶体的吸收光谱和荧光光谱进行了分析。与Yb掺杂原子数分数为5%的Yb∶YAG晶体进行了对比,得出采用940 nm激光二极管(LD)抽运晶体最为合适。原子数分数为0.5%的Yb∶YAG晶体相对于原子数分数为5%的Yb∶YAG晶体自吸收效应的影响要小。测量了原子数分数为0.5%的Yb∶YAG晶体的荧光寿命为0.95 ms,与理论值很接近。因此采用原子数分数为0.5%的Yb∶YAG晶体作为激光工作物质将有利于高效、小型集成化的固体激光器的发展。

关键词：材料光谱 Yb:YAG晶体吸收光谱荧光光谱自吸收荧光寿命

Acquired sensorineural hearing loss,oxidative stress,and microRNAs

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Neural Regeneration Research 2025年第9期20卷 2513-2519页

作者： Desmond A.Nunez Ru c.Guo Division of Otolaryngology–Head&Neck Surgery Department of SurgeryFaculty of MedicineThe University of British ColumbiaVancouverBCCanada Division of Otolaryngology–Head&Neck Surgery Gordon&Leslie Diamond Health Care CentreVancouver General HospitalVancouverBCCanada Faculty of Medicine–The University of British columbia VancouverBCCanada

Hearing loss is the third leading cause of human ***-related hearing loss,one type of acquired sensorineural hearing loss,is largely responsible for this escalating global health ***-induced,ototoxic,and idiopathic sudden sensorineural are other less common types of acquired hearing *** etiology of these conditions is complex and multi-fa ctorial involving an interplay of genetic and environmental *** stress has recently been proposed as a likely linking cause in most types of acquired sensorineural hearing *** non-coding RNA sequences known as microRNAs(miRNAs)have increasingly been shown to play a role in cellular hypoxia and oxidative stress responses including promoting an apoptotic *** hair cell death is a central histopathological finding in sensorineural hearing *** these cells do not regenerate in humans,it underlies the irreversibility of human age-related hearing *** EMBASE,Ovid MEDLINE,Web of Science core collection,and *** databases over the period August 1,2018 to July 31,2023 were searched with"hearing loss,""hypoxamiRs,""hypoxia,""microRNAs,""ischemia,"and"oxidative stress"text words for English language primary study publications or registered clinical *** red clinical trials known to the senior author we re also assessed.A total of 222studies were thus *** excluding duplicates,editorials,retra ctions,secondary research studies,and non-English language articles,39 primary studies and clinical trials underwent full-text *** resulted in 11 animal,in vitro,and/or human subject journal articles and 8 registered clinical trial database entries which form the basis of this narrative *** miR-34a and miR-29b levels increase with age in *** miRNAs were demonstrated in human neuroblastoma and murine cochlear cell lines to target Sirtuin 1/peroxisome proliferato r-activated receptor gamma coactivator-1-alpha(SIRT1/P Gc-1α),SIRT

关键词： hearing loss hypoxia microRNAs oxidative stress sensorineural

Multiple sclerosis is at a checkpoint: advancing the program

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Neural Regeneration Research 2025年第3期20卷 811-812页

作者： Brandon c.Smith jessica L.Williams Department of Neurosciences Lerner Research InstituteCleveland ClinicClevelandOHUSA Department of Biological Geologicaland Environmental SciencesCleveland State UniversityClevelandOHUSA

Multiple sclerosis(MS) is a chronic inflammatory and demyelinating disease of the central nervous system(cNS). Patients with MS experience sensory and motor function loss due to myelin and/or axon damage perpetuated b... 详细信息

关键词： Hauser sclerosis damage

APPLIcATION OF WAVELET TRANSFORM ON DIAGNOSIS AND PREDIcTION OF MILLING cHATTER

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chinese Journal of Mechanical Engineering 2007年第3期20卷 67-70页

作者： LUO Ming-je Department of Mechanical Engineering R&D Center for Membrane Technology Chung Yuan Christian University Chung-Li 32023 Taiwan China

In order to avoid the accuracy deterioration or tool damage caused by milling chatter, it is necessary to have an efficient and reliable diagnosis system that can on-line predict/detect the occur-rence of chatter. The diagnosis/predicting system proposed is to on-line process and analysis the vi-bration signals of the milling machine measured by accelerometers. According to the analysis results, the system will be able to detect/predict the occurrence of the chatter. The diagnosis algorithm is, first, collecting both the normal signals and chatter signals from milling processes, and then, converting the signals through wavelet transform and fast Fourier transform （FFT）. Since the converted chatter sig-nals exhibit different characteristics from the normal signals, through defining the characteristic val-ues, such as root-mean-square value, max value, and ratio of peak value to root-mean-square value, etc, a diagnosis reference library that contains the distribution of these characteristic values is built for diagnosis. When a diagnosis is executing, the characteristic value of the measured signals is con-trasted with the diagnosis reference. The approach index which shows the possibility of occurrence of milling chatter will, then, be calculated through the diagnosis system. cutting experiments are con-ducted to verify the proposed diagnosis system. The results show the success of early chatter detecting for the system.

关键词： chatter On-line diagnosis Prediction Wavelet transform

Applying machine learning techniques to predict detonation initiation fromhot spots

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Energy and AI 2022年第3期9卷 121-127页

作者： je Ir Ryu Department of Mechanical Engineering University of California-BerkeleyBerkeleyCA 94720USA

As hot spots can be a source of detonation initiation by autoignition in a reactive mixture, understanding hotspot initiated detonation is significantly important for energy-related applications of detonation. Although theZel’dovich reactivity gradient theory is extremely useful to predict reaction propagation modes from hot spots,the prediction is limited due to the changes in the unburnt mixture during the induction time. In the currentstudy, machine learning based estimation methods by training the numerical simulation result data set aresuggested to avoid the extensive and empirical effort to find initial conditions of hot spot initiated detonationin inhomogeneous mixtures. The data set was obtained from the detailed numerical simulations with variousconditions of hot spots and divided into training and test data sets. Some variables were normalized withothers to avoid multicollinearity. Three different machine learning techniques, logistic regression, classificationand regression trees, and artificial neural network, were utilized to develop prediction models. Using thedeveloped models by machine learning approaches, the modes of hot spot initiated reaction front propagationcan be predicted without computationally expensive numerical simulations. The accuracies of the machinelearning based prediction models were significantly improved compared to the baseline model simply usingthe Zel’dovich reactivity gradient theory. These models can be utilized as preliminary prediction methods ofhot spot induced detonation initiation conditions for further detailed numerical simulations and dominantinput variables.

关键词： Detonation Deflagration Hydrogen Syngas Logistic regression cART Artificial neural network