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Natural Products and Bioprospecting 2022年第1期12卷 137-157页

作者： Aluru Rammohan Albert F.Khasanov Dmitry S.Kopchuk Duvvuru Gunasekar grigory v.zyryanov Oleg N.Chupakhin Ural Federal University 19 Mira St.Ekaterinburg 620002Russian Federation Natural Products Division Department of ChemistrySri Venkateswara UniversityTirupati 517502India Ural Division of the Russian Academy of Sciences I.Ya.Postovsky Institute of Organic Synthesis22 S.Kovalevskoy St.Ekaterinburg 620219Russian Federation

The development of highly facile synthetic procedures for the expedient synthesis of complex natural molecules is always in *** this aspect,the Diels-Alder reaction(DAR)has a versatile approach to the synthesis of complex natural compounds and highly regio-/stereoselcetive heterocyclic ***,α-pyrone and terpeno-quinone are two versatile key intermediates that are prevalent in various bioactive natural compounds for instance,(±)-crinine,(±)-joubertinamine,(±)-pancratistatin,(−)-cyclozonarone,and 8-ephipuupehedione,***,the current review summarizes the Diels-Alder reaction application ofα-pyrone and terpenoquinone to the construc-tive synthesis of various natural products over the past two decades(2001-2021).Equally,it serves as a stencil for the invention and development of new synthetic strategies for high-complex molecular structured natural and heterocy-clic molecules.

关键词： α-Pyrone Diels-Alder reaction(DAR) Marine natural compounds Terpenoquinone Total synthesis

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

基于正电荷和光热协同效应的新型半导体聚合物纳米抗菌材料

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高等学校化学学报 2020年第4期41卷 670-681页

作者：潘国勇荔雅文马立军马宇帆艾文婷王振国侯欣慧戈里戈瑞·齐格亚诺夫王卓化工资源有效利用国家重点实验室北京软物质科学与工程高精尖创新中心北京化工大学化学学院北京100029 乌拉尔联邦大学俄罗斯联邦叶卡捷琳堡620002 普斯托夫斯基有机合成研究所俄罗斯科学院乌拉尔分院俄罗斯联邦叶卡捷琳堡620108

由于抗生素的不当使用和细菌多药耐药的出现,迫切需要开发新的抗菌剂.本文制备了具有光热转换性能的正电荷半导体高分子材料及具有协同抗菌活性的半导体聚合物纳米粒子(SP-PPh 3 NPs).SP-PPh 3 NPs的光热转化效率为43.8%.带正电荷的SP-P... 详细信息

由于抗生素的不当使用和细菌多药耐药的出现,迫切需要开发新的抗菌剂.本文制备了具有光热转换性能的正电荷半导体高分子材料及具有协同抗菌活性的半导体聚合物纳米粒子(SP-PPh 3 NPs).SP-PPh 3 NPs的光热转化效率为43.8%.带正电荷的SP-PPh 3 NPs可以附着在细菌上,有助于将热量有效传递给细菌.在热和正电荷的协同作用下,SP-PPh 3 NPs对革兰氏阴性大肠杆菌(\%***\%)和革兰氏阳性金黄色葡萄球菌(\%***\%)均具有抗菌活性,其对二者的体外抑菌率分别为99.9%和98.6%.此外,SP-PPh 3 NPs具有良好的生物相容性,对小鼠的主要器官几乎无副作用.对细菌感染的小鼠皮肤伤口用SP-PPh 3 NPs治疗12 d后,伤口可以很好地愈合.

关键词：半导体聚合物正电荷纳米颗粒光热转换抗菌

Giant non-linear susceptibility of hydrogenic donors in silicon and germanium

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Light(Science & Applications) 2019年第1期8卷 624-630页

作者： Nguyen H.Le grigory v.Lanskii Gabriel Aeppli Benedict N.Murdin Advanced Technology Institute and SEPNet University of SurreyGuildford GU27XHUK Institute of Monitoring of Climatic and Ecological Systems SB RAS 10/3 Academical Ave.Tomsk 634055Russia Laboratory for Solid State Physics ETH ZurichZurich CH-8093Switzerland Institut de Physique EPF LausanneLausanne CH-1015Switzerland Paul Scherrer Institut VilligenPSI CH-5232Switzerland

Implicit summation is a technique for the conversion of sums over intermediate states in multiphoton absorption and the high-order susceptibility in hydrogen into simple ***,we derive the equivalent technique for hydrogenic impurities in multi-valley *** the absorption has useful applications,it is primarily a loss process;conversely,the non-linear susceptibility is a crucial parameter for active photonic *** Si:P,we predict the hyperpolarizability ranges from χ^((3))/n_(3D)=2.9 to 580×10^(−38 )m^(5)/v^(2) depending on the frequency,even while avoiding *** samples of a reasonable density,n3D,and thickness,L,to produce thirdharmonic generation at 9 THz,a frequency that is difficult to produce with existing solid-state sources,we predict that χ^((3)) should exceed that of bulk InSb and χ^((3))L should exceed that of graphene and resonantly enhanced quantum wells.

关键词： susceptibility hydrogenic absorption

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

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 a priori (se-quentially) adapted meshes and study its *** scheme on a priori adapted meshes is constructed using a majorant function for the singular component of the discrete solution,which allows us to find a priori a subdomain where the computed solution requires a further *** subdomain is defined by the perturbation parameterε,the step-size of a uniform mesh in x,and also by the required accuracy of the discrete solution and the prescribed number of refinement iterations K for im- proving the *** solve the discrete problems aimed at the improvement of the solution,we use uniform meshes on the *** error of the numerical so- lution depends weakly on the parameterε.The scheme converges almostε-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：有限微分奇异扰动对流扩散问题收敛性

Numerical method for axial motion artifact correction in retinal spectral-domain optical coherence tomography

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Frontiers of Optoelectronics 2020年第4期13卷 393-401页

作者： Sergey Yu.KSENOFONTOv Pavel A.SHILYAGIN Dmitry A.TERPELOv valentin M.GELIKONOv grigory v.GELIKONOv BioMedTech Lie Nizhny Novgorod 603155Russia Institute of Applied Physics of the Russian Academy of Science Nizhny Novgorod 603950Russia

A numerical method that compensates image distortions caused by random fluctuations of the distance to an object in spectral-domain optical coherence tomography(SD OCT)has been proposed and verified *** proposed method is based on the analysis of the phase shifts between adjacent scans that are caused by micrometer-scale displacements and the subsequent compensation for the displacements through phase-frequency correction in the spectral *** efficiency of the method is demonstrated in model experiments with harmonic and random movements of a scattering object as well as during in vivo imaging of the retina of the human eye.

关键词： optical coherence tomography(OCT) motion artifact correction retinal imaging numerical method

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

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