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掺硫硒化镓晶体在太赫兹波段的光学特性

光学精密工程 2011年第2期19卷 354-359页

作者：罗志伟古新安朱韦臻唐维聪 ANDREEv YURY lanskii grigory MOROZOv Alexander ZUEv vladimir 交通大学电子物理系中国新竹30010 Institute of Monitoring of Climatic and Ecological Systems of Siberian Branch of Russian Academy of Sciences Tomsk Russia

利用太赫兹时域光谱技术测量了掺硫硒化镓（GaSe1-xSx）晶体在太赫兹波段的光学参数,包括折射系数、吸收系数等。使用自由空间电光取样法获得了太赫兹电磁波的脉冲波形,对不同硫掺杂量的硒化镓晶体进行了研究,在硫的掺杂量为0,0.01,0.14... 详细信息

利用太赫兹时域光谱技术测量了掺硫硒化镓（GaSe1-xSx）晶体在太赫兹波段的光学参数,包括折射系数、吸收系数等。使用自由空间电光取样法获得了太赫兹电磁波的脉冲波形,对不同硫掺杂量的硒化镓晶体进行了研究,在硫的掺杂量为0,0.01,0.14,0.26,0.37时,在0.22.0 THz测得了GaSe1-xSx的折射系数、吸收系数等光学参数。此外还在吸收光谱上观察到E′^（2）和E″^（2）两个声子振动模态,其强度与频率会随着硫的掺杂量而改变,且即使是微量的硫掺杂也会影响吸收光谱上的声子振动模态。最后,在相位匹配ee-e的条件下,模拟了利用锁模钛蓝宝石激光使此类晶体产生太赫兹辐射的可能性。

关键词：掺硫硒化镓晶体太赫兹辐射太赫兹时域光谱

Pendulum-type laser strainmeter

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Earthquake Science 2015年第4期28卷 311-317页

作者： grigory Ivanovich Dolgikh v.I.Il'ichev Pacific Oceanological Institute of the Far Eastern Branch Russian Academy of Sciences

Constructive disposition principles of the basic optical units of Michelson interferometers are used in making one-coordinate laser strainmeters of unequal-arm type. The fundamental advantages of pendulurn-type laser ... 详细信息

关键词： Amplitude-frequency characteristic Classical-type laser strainmeter Elastic wave Infrasound Pendulum-type laser strainmeter

Peliosis hepatis complicated by portal hypertension following renal transplantation

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World Journal of Gastroenterology 2020年第34期26卷 5220-5222页

作者： grigory Demyashkin Margarita Zatsepina Department of Pathology Sechenov UniversityMoscow 119146Russia

Peliosis hepatis is a rare benign disease,but in last years the number of identified cases has *** disease is known to be sometimes accompanied by hepatocellular *** the recent article,Yu et al describe a case of liver peliosis,characterized by an increased proliferative ***,additional diagnosis of patients should include analyzing other tumor markers expression in order to assess the risk of malignant cell transformation in peliosis hepatis.

关键词： Peliosis hepatis Hepatocellular carcinoma Survivin Epithelial-mesenchymal transition

A Finite Difference Scheme on a Priori Adapted Meshes for a Singularly Perturbed Parabolic Convection-Diffusion Equation

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Numerical Mathematics(Theory,Methods and Applications) 2008年第2期1卷 214-234页

作者： grigory I.Shishkin Institute of Mathematics and Mechanics Ural Branch of Russian Academy of Sciences

A boundary value problem is considered for a singularly perturbed parabolic convection-diffusion equation; we construct a finite difference scheme on α priori （sequentially） adapted meshes and study its convergence. The scheme on α priori adapted meshes is constructed using a majorant function for the singular component of the discrete solution, which allows us to find α priori a subdomain where the computed solution requires a further improvement. This subdomain is defined by the perturbation parameter ε, the step-size of a uniform mesh in χ, and also by the required accuracy of the discrete solution and the prescribed number of refinement iterations K for improving the solution. To solve the discrete problems aimed at the improvement of the solution, we use uniform meshes on the subdomains. The error of the numerical solution depends weakly on the parameter ε. The scheme converges almost ε-uniformly, precisely, under the condition N^-1 = o （ε^v）, where N denotes the number of nodes in the spatial mesh, and the value v = v（K） can be chosen arbitrarily small for suitable K.

关键词： Singular perturbations convection-diffusion problem piecewise-uniform mesh α priori adapted mesh almost ε-uniform convergence

An efficient synthetic approach towards new 5,5'-diaryl-2,2'-bipyridine-based fluorophores

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Chinese Chemical Letters 2017年第5期28卷 1099-1103页

作者： Alexey P.Krinochkin Dmitry S.Kopchuk Nikolay v.Chepchugov grigory A.Kim Igor S.Kovalev Matiur Rahman grigory v.Zyryanov Adinath Majee vladimir L.Rusinov Oleg N.Chupakhin Ural Federal University Yekaterinburg 620002Russian Federation Postovsky Institute of Organic Synthesis of RAS(Ural Division) Yekaterinhurg 620990Russian Federation Department of Chemistry Visva-Bharati(A Central University)Santiniketan 731235India

An efficient approach has been developed for the synthesis of 5,5＇-diaryl-2,2＇-bipyridines via their 1,2,4-triazine *** notable advantages of the present method are：The possibility of varying the aromatic substituents in the positions 5 and 5＇ of bipyridine core and the possibility for obtaining 2,2＇-bipyridines bearing a fused cyclopentene core to increase the solubility in organic *** 5,5＇-diaryl-2,2＇-bipyridines exhibited an intense emission in a range of ca.422-521 nm in acetonitrile solution;depending on the nature of the aromatic substituents and the presence of annulated cyclopentene *** from that,the significant bathochromic shifts of the both absorption and emission maxima were observed in comparison with a number of previously described similar *** some cases the significant increasing of the fluorescence quantum yields took place.

关键词： 2 2'-Bipyridines 1 2 4-Triazines Aza-Diels-Alder reaction Fluorescence

Assessing workability of greased bearings after long-term storage

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Friction 2019年第5期7卷 489-496页

作者： Michael vARENBERG Yuri KLIGERMAN grigory HALPERIN Saad NAKAD Haytam KASEM George W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA30332USA Department of Mechanical Engineering Technion-Israel Institute of TechnologyHaifa32000Israel Department of Mechanical Engineering Azrieli College of EngineeringJerusalem9103501Israel

Here, we developed a technique to assess the workability of sealed-for-life greased rolling bearings after a long-term storage. In this framework, we devised a model of equivalent transition between the conditions of natural ageing under daily and seasonally fluctuating temperature, and the conditions of accelerated thermal ageing at a constant high temperature. The tested bearings were thermally aged, and then their steady state friction and outer ring temperature were examined in a custom high-speed spindle. These results were compared to the performance of a reference new bearing tested under the same loading conditions. Our findings suggest that long-term storage can significantly degrade the performance of sealed-for-life greased rolling bearings. However, a proper running-in can substantially deter the ageing-driven degradation of the bearings.

关键词： grease lubrication ball bearings thermal ageing lubricant degradation

Dynamic failure of dry and fully saturated limestone samples based on incubation time concept

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第1期9卷 125-134页

作者： Yuri v. Petrov Ivan v. Smirnov grigory A. volkov Andrei K. Abramian Anatoliy M. Bragov Stanislav N. verichev Saint Petersburg University Universitetskaya nab. 7-9 Saint Petersburg 199034 Russia Institute of Problems of Mechanical Engineering Russian Academy of Sciences Bolshoj pr. 61 V.O. Saint Petersburg 199178 Russia Lobachevsky State University of Nizhni Novgorod Prospekt Gagarina 23 Nizhny Novgorod 603950 Russia Allseas Engineering B.v. Poortweg 12 Delft 2612 PA The Netherlands

This paper outlines the results of experimental study of the dynamic rock failure based on the comparison of dry and saturated limestone samples obtained during the dynamic compression and split tests. The tests were performed using the Kolsky method and its modifications for dynamic splitting. The mechanical data(e.g. strength, time and energy characteristics) of this material at high strain rates are obtained. It is shown that these characteristics are sensitive to the strain rate. A unified interpretation of these rate effects, based on the structuraletemporal approach, is hereby presented. It is demonstrated that the temporal dependence of the dynamic compressive and split tensile strengths of dry and saturated limestone samples can be predicted by the incubation time criterion. Previously discovered possibilities to optimize(minimize) the energy input for the failure process is discussed in connection with industrial rock failure processes. It is shown that the optimal energy input value associated with critical load, which is required to initialize failure in the rock media, strongly depends on the incubation time and the impact duration. The optimal load shapes, which minimize the momentum for a single failure impact, are demonstrated. Through this investigation, a possible approach to reduce the specific energy required for rock cutting by means of high-frequency vibrations is also discussed.

关键词： Dynamic strength Incubation time criterion Split Hopkinson pressure bar(SHPB) test Tensile strength Compressive strength Water-saturated limestone vibration-assisted rock cutting

Doped GaSe crystals for laser frequency conversion

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Light(Science & Applications) 2015年第1期4卷 47-58页

作者： Jin Guo Ji-Jiang Xie Dian-Jun Li Gui-Long Yang Fei Chen Chun-Rui Wang Lai-Ming Zhang Yury M Andreev Konstantin A Kokh Gregory v.lanskii valery A Svetlichnyi State Key Laboratory of Laser Interaction with Matter Changchun Institute of OpticsFine Mechanics and PhysicsCASChangchun 130033China Innovation Laboratory of Electro-Optical Countermeasures Technology Changchun Institute of OpticsFine Mechanics and PhysicsCASChangchun 130033China Laboratory of GeosphereBiosphere Interactions Institute of Monitoring of Climatic and Ecological SystemsSB RASTomsk 634055Russia Laboratory of Advanced Materials and Technologies Siberian Physical-Technical Institute of Tomsk State UniversityTomsk 634050Russia Crystal Growth Laboratory Institute of Geology and MineralogySB RASNovosibirsk 630090Russia Novosibirsk State University Novosibirsk 630090Russia

In this review,we introduce the current state of the art of the growth technology of pure,lightly doped,and heavily doped(solid solution)nonlinear gallium selenide(GaSe)crystals that are able to generate broadband emission from the near infrared(IR)(0.8 mm)through the mid-and far-IR(terahertz(THz))ranges and further into the millimeter wave(5.64 mm)*** the first time,we show that appropriate doping is an efficient method controlling a range of the physical properties of GaSe crystals that are responsible for frequency conversion efficiency and exploitation *** appropriate doping,uniform crystals grown by a modified technology with heat field rotation possess up to 3 times lower absorption coefficient in the main transparency window and THz ***,doping provides the following benefits:raises by up to 5 times the optical damage threshold;almost eliminates two-photon absorption;allows for dispersion control in the THz range independent of the mid-IR dispersion;and enables crystal processing in arbitrary directions due to the strengthened ***,doped GaSe demonstrated better usefulness for processing compared with GaSe grown by the conventional technology and up to 15 times higher frequency conversion efficiency.

关键词： frequency conversion GaSe solid solution crystal THz

In vivo assessment of structural changes of the urethra in lower urinary tract disease using cross-polarization optical coherence tomography

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Journal of Innovative Optical Health Sciences 2020年第6期3卷 55-70页

作者： Elena B.Kiseleva Alexander A.Moiseev Anton S.Kuyarov Muhammat A.Molvi grigory v.Gelikonov Anna v.Maslennikova Olga S.Streltsova Privolzhsky Research Medical University 10/1 Minin and Pozharsky Square 603005 Nizhny NovgorodRussia Institute of Applied Physics Russian Academy of Sciences Ulyanova Street 46603950Nizhny NovgorodRussia

The paper presents the results of a study of the female urethra in cases of urethral pain syndrome(UPS)and inflammatory diseases of the lower urinary tract using cross-polarization optical coherence tomography(CP OCT).Urethral wall structure was studied in 86 patients;233 CP OCT images were collected.A comparative qualitative analysis of three groups of CP OCT images—"norm","Inflammation"and"UPS"—identified that despite the absence of a clear inflammatory factor in the patient's examination,the urethral tissues in UPS were in an altered *** changes in the urethral wall with UPS and in cases of inflammation were *** a point scale,three experts independently performed visual scoring of the CP OCT *** parameters:epithelial contrast,cavities and the minimum signal depth in the co-channel were *** was found that,individually,the parameters correlate only weakly with the *** under the receiver operating characteristic(ROC)curve was from 0.51 to *** joint use of a number of visual signs has a greater diagnostic value than the use of the criteria *** under the ROC curve using the developed cumulative criterion reached up to *** study could form the basis of a scoring system for assessing the state of the urethral tract using CP OCT images in real *** CP OCT method provides information on the state of urethral tissues that cannot be obtained with traditional cystoscopy.

关键词： Cross-polarization optical coherence tomography urethral pain syndrome connective tissue visual analysis of images automatic classification of images