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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

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

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

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

Spectral Investigations of Hybrid nanostructures Including Modified Fullerene C60 and Carbazole-Derivative Fluorophore

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Advances in nanoparticles 2014年第3期3卷 77-82页

作者： Evgeny P. Grebennikov grigory E. Adamov valery n. Charushin Konstantin S. Levchenko Gennady L. Rusinov Evgeny v. Zinoviev Roman A. Irgashev Pavel S. Shmelin Institute of Organic Synthesis Urals Branch of Russian Academy of Sciences Ekaterinburg Russia OJSC “CSRIT Technomash” Moscow Russia

Hybrid nanostructures including modified fullerene C60 and fluorophoric (E)-2-Cyano-3-(9-ethyl-9Н-carbazole-3-yl)-acrylic acid (cyanoacrylic acid I) were created. Spectral properties (absorption and luminescence spectra) of the hybrid nanostructures were investigated. It was established what molecules C60 strongly affected spectral properties of cyanoacrylic acid I in the hybrid nanostructures. Luminescence quenching of fluorophore and a change of luminescence features were observed in the hybrid nanostructures.

关键词： Hybrid nanostructures Water-Soluble Fullerene C60 Luminescence Quenching

Molybdenum Carbide nano-Powder for Production of Mo-99 Radionuclides

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World Journal of nuclear Science and Technology 2012年第2期2卷 58-63页

作者： vladimir D. Risovany Konstantin v. Rotmanov Genady I. Maslakov Yury D. Goncharenko grigory A. Shimansky Aleksandr I. Zvir Irina M. Smirnova Irina n. Kuchkina Joint Stock Company State Scientific Center—Research Institute of Atomic Reactors Dimitrovgrad Russia

At present, there are two ways to produce 99Mo in a reactor: 1) fission process—from U fission product by reaction 235U (n, f) 99Mo and 2) activation process—by radiation capture reaction 98Mo (n, γ) 99Mo. This paper presents the results of experiments performed with molybdenum carbide nano-powder to produce 99Mo. These results show the implementation of the above idea in practice.

关键词： Carbide nano-Powder Molybdenum-99 Activation Process Fission Process