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Nano Research 2015年第6期8卷 2063-2072页

作者： Andrei T. Matveev Konstantin L. Firestein Alexander E. Steinman Andrey M. Kovalskii oleg I. Lebedev Dmitry v. Shtansky Dmitri Golberg National University of Science and Technology 'MISIS' Leninskiy prospect 4 Moscow 119049 Russia CRISMAT UMR 6508 CNRS-ENSICAEN 6BdMarechalJuin Caen 14050 France Institute for Materials Science (NIMS) Namiki 1 Ibaraki Tsukuba 3050044 Japan

High-purity straight and discrete multiwalled boron nitride nanotubes （BNNTs） were grown via a boron oxide vapor reaction with ammonia using LiNO3 as a promoter. Only a trace amount of boron oxide was detected as an impurity in the BNNTs by energy-dispersive X-ray （EDX） and Raman spectroscopies. Boron oxide vapor was generated from a mixture of B, FeO, and MgO powders heated to 1,150 ℃, and it was transported to the reaction zone by flowing ammonia. Lithium nitrate was applied to the upper side of a BN bar from a water solution. The bar was placed along a temperature gradient zone in a horizontal tubular furnace. BNNTs with average diameters of 30-50 nm were mostly observed in a temperature range of 1,280-1,320 ℃. At higher temperatures, curled polycrystalline BN fibers appeared. Above 1,320 ℃, the number of BNNTs drastically decreased, whereas the quantity and diameter of the fibers increased. The mechanism of BNNT and fiber growth is proposed and discussed.

关键词： boron nit-ride nanotubes CvD lithium nitrate lithium borate BNNT growth mechanism

NOISE REDUCTION METHOD FOR OCT IMAGES BASED ON EMPIRICAL MODE DECOMPOSITION

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Journal of Innovative Optical Health Sciences 2013年第2期6卷 17-21页

作者： oleg O.MYAKININ DMITRY v.KORNILIN IvAN A.BRATCHENKO vALERIY P.ZAKHAROv ALEXANDER G.KHRAMOv Photonics Laboratory Samara State Aerospace University Moskovskoe shosse 34 SamaraRussia 443086Russia Laboratory of Laser Measurements Image Processing System Institute of Russian Academy of Science Molodogvardeyskaya Street 151 Samara 443001Russia

In this paper,the new method for OCT images denoizing based on empirical mode decomposition(EMD)is *** noise reduction is a very important process for following operations to analyze and recognition of tissue *** method does not require any additional operations and hardware *** basics of proposed method is *** improvement of noise suppression om example of edge detection procedure using the classical Canny's algorithm without any additional pre-and post-proc essing operations is *** of raw-segmentation in the automatic diagnostic process between a tissue and a mesh implant is shown.

关键词： Optical coherence tomography empirical mode decomposition denoizing thresholding

Pathogenesis of Cancer: Cancer Reparative Trap

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Journal of Cancer Therapy 2015年第5期6卷 399-412页

作者： oleg v. Bukhtoyarov Denis M. Samarin Laboratory of Psychoimmunology Immanuel Kant Baltic Federal University Kaliningrad Russia Department of Psychological Studies Scientific-Research Institute of the Russia’s Federal Penitentiary Service Moscow Russia

Cancer is one of the leading causes of death in the world while the long-term prognosis is still unfavorable, despite the enormous efforts in the search for effective anti-cancer drugs. We think that the obstacle for creating of effective anti-cancer drugs could be existing idea that the basis of cancer is caused by the damage of the genetic apparatus of the cell. In this paper, we present the pathogenesis of cancer which is based on the formation of the special sustainable pathophysiological state of the organism what we call the state of “cancer reparative trap”. The essence of this pathophysiological state of the organism is in the reparative orientation of the immune system of cancer patients, when constant tissue repair is accompanied by systemic suppression of the anti-tumor immunity. Specifically, during the long-term exposure to carcinogens (exogenous and/or endogenous), the continuous tissue damage occurs which induces permanent stimulation of cell proliferation (imbalanced Th1 vival of the malignantly transformed cells, formed by the action of carcinogens. The determining role of the imbalance in the autonomous nervous system (simpathetic/hypersympathetic dominance) in the development, maintenance and generalization of the cancer process has been shown. The explanation of a number of phenomena has been presented: the cell resistance to chemotherapy, and the phenomenon of cancer cell dormancy. The promising approaches for the cancer management in clinical practice have been proposed.

关键词： Carcinogenesis Cancer Pathophysiology Anti-Tumor Immunity Cancer Reparative Trap

The Exolife： Gas Dust Streams and Seeds

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Journal of Earth Science and Engineering 2015年第3期5卷 203-214页

作者： oleg B. Khavroshkin vladislav v. Tsyplakov Institute of Physics of the Earth Russian Academy of Science Moscow 12399 Russia

The hypothesis that bacteria and protozoa microorganisms are able to travel from one planet to another and become of exolife was not taken seriously by the scientific community for a long time. However at the end of the 20th century the situation changed dramatically. Firstly, in 1990, meteorites consisting of Martian rocks were found. Secondly, it became clear that many microorganisms especially bacteria spores have an uncanny ability to endure the rugged environment of the outer space for a long time and then re-activate in a more favorable environment. If we compare these findings, the idea of interplanetary transmigration of the simplest forms of life on meteoroids ceases to look so illusory. The final dot in this issue was made by the works of academician Rozanov, and later Hoover （Professor Richard B. Hoover） through the discovery of fossilized microbes inside of a meteorite massif, that is to say, seeds of life. However, to tie only the simplest forms of life to meteorites or comets is to introduce strong constraints on the likelihood of delivery of seeds （spores of life） to Earth for many obvious reasons. Besides, exobiology does not negate the problem of origin of life, and transfers it into the era of the young universe. Therefore, it is necessary to consider in detail the essence of seeds of life or cosmic particles of dust and gas-dust streams as their carriers, their penetration path to Earth and forms of their existence.

关键词： Gas-dust streams spores of life and space viruses comets and meteoroids biological hazards.

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

Computer simulation of shearing deformation in polymer systems with polar groups

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Journal of Advanced Dielectrics 2020年第3期10卷 37-42页

作者： Olga G.Maksimova oleg S.Piskunov Roman A.Gerasimov Olga S.Baruzdina Andrew v.Maksimov Laboratory of Mathematical and Computer Modeling Cherepovets State University 5 Lunacharskii Av.Cherepovets 162600Russian Federation Department of Physics Cherepovets State University Lunacharskii Av. Cherepovets 162600Russian Federation

In this work,shear strain modeling in materials consisting of a thin polymer layer(~15 nm),adhesive bonded to a rigid substrate,considered not to be impacted by deformation,was performed.A discrete-continuum model of chains system with a given stiffness with polar groups is *** polymer chain was considered in the framework of the persistene model,and the polar groups were based on the lattice model on the tetragonal *** was assumed that the main contribution to the energy of interchain interactions is due to the potential of the polar groups and was calculated using the Metropolis *** potential interactions between the nearest polar groups of chains included the energy of dipole–dipole interactions(Keesom energy)and the Lennard–Jones *** is taken into account that the possible orientations of the polar groups are determined by the average elongation of the *** showed that the dependence of free energy on the interchain distance has two *** first minimum is characterized by the orientational ordering of the polar groups,the second—by their disordered *** depth and position of the minima depend on temperature,bending stiffness of the chain,the modulus of the dipole moment of the polar groups and the depth of the potential well in the Lennard–Jones energy.A step-by-step simulation of shear strain in a polymer layer in an orientationally disordered state was carried *** obtained stress–strain diagrams make it possible to estimate the value of the elastic limit and also to determine the stresses at the points of phase transitions from a disordered to an orientationally ordered state.

关键词： Polymer systems polar group shearing deformations PvDF Monte Carlo method

Improving sintering kinetics and compositional homogeneity of Inconel 625 superalloy open-cell foams made by suspension impregnation method

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Transactions of Nonferrous Metals Society of China 2021年第8期31卷 2388-2401页

作者： oleg SMORYGO vitali MIKUTSKI Anastasia vAZHNOvA viachaslau HANCHAROU Serguei TIKHOv vinod Kumar JANAGAM Amol Anant GOKHALE O.v Roman Powder Metallurgy Institute 41Platonov str.Minsk 220005Belarus Boreskov Institute of Catalysis Siberian BranchRussian Academy of Sciences5pr.LavrentievaNovosibirsk 630090Russia Defence Metallurgical Research Laboratory KanchanbaghHyderabad 500058India Indian Institute of Technology Bombay PowaiMumbai 400076India

Open-cell Inconel 625 superalloy foams were prepared by suspension impregnation method which involves replication of pure nickel foam ligaments with a mixed powder suspension and subsequent heat *** objective of the present study is to find a suitable method ensuring complete densification of the superalloy foam ligaments without using low-melting additives and achieving uniform chemical composition at moderate sintering *** prepared using the above methodology were evaluated for the microstructure and compositional variation across the foam ligaments by scanning electron microscopy(SEM)coupled with electron dispersive spectroscopy(EDS).Quasi-static compressive properties of the foams were *** is shown that if elemental powders of Cr,Mo and Ni are used as additives to the superalloy powder suspension,high ligament density with uniform chemical composition conforming to the Inconel 625 specification is achieved at moderate sintering *** results are attributed to the formation of low melting eutectics and to acceleration of the diffusion kinetics due to the non-equilibrium thermodynamic conditions created by large compositional gradients in the presence of elemental powders.

关键词： superalloy foam suspension replication sintering diffusion microstructure

Numerical optimisation of a classical stochastic system for targeted energy transfer

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Theoretical & Applied Mechanics Letters 2023年第3期13卷 170-176页

作者： oleg Gaidai Yubin Gu Yihan Xing Junlei Wang Daniil Yurchenko Shanghai Engineering Research Center of Marine Renewable Energy Shanghai Ocean UniversityChina School of Mechanical and Electrical Engineering Guilin University of Electronic TechnologyChina Department of Machine Building and Materials TechnologyUniversity of StavangerNorway School of Mechanical and Power Engineering Zhengzhou UniversityChina Institute for Sound and vibration Research University of SouthamptonUK

The paper studies stochastic dynamics of a two-degree-of-freedom system,where a primary linear system is connected to a nonlinear energy sink with cubic stiffness nonlinearity and viscous *** the primary mass is subjected to a zero-mean Gaussian white noise excitation,the main objective of this study is to maximise the efficiency of the targeted energy transfer in the system.A surrogate optimisation algorithm is proposed for this purpose and adopted for the stochastic *** optimisations are conducted separately for the nonlinear stiffness coefficient alone as well as for both the nonlinear stiffness and damping coefficients *** different optimisation cost functions,based on either energy of the system’s components or the dissipated energy,are *** results demonstrate some clear trends in values of the nonlinear energy sink coefficients and show the effect of different cost functions on the optimal values of the nonlinear system’s coefficients.

关键词： Targeted energy transfer Surrogate optimisation Stochastic system Random vibration

Assessment on facile Diels-Alder approach of α-pyrone and terpenoquinone for the expedient synthesis of various natural scaffolds

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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

Negative thermal expansion in one-dimension of a new double sulfate AgHo(SO_(4))_(2)with isolated SO_4 tetrahedra

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Journal of Materials Science & Technology 2021年第17期76卷 111-121页

作者： Yuriy G.Denisenko victor v.Atuchin Maxim S.Molokeev Naizheng Wang Xingxing Jiang Aleksandr S.Aleksandrovsky Alexander S.Krylov Aleksandr S.Oreshonkov Alexander E.Sedykh Svetlana S.volkova Zheshuai Lin oleg v.Andreev Klaus Müller-Buschbaum Institute of Chemistry Tyumen State University.Tyumen625003Russia Institute of Inorganic and Analytical Chemistry Justus-Liebig-University of Giessen35392Giessen.Germany Department of General and Special Chemistry Industrial University of TyumenTyumen625000Russia Laboratory of Optical Materials and Structures Institute of Semiconductor PhysicsSB RASNovosibirsk630090Russia Laboratory of Semiconductor and Dielectric Materials Novosibirsk State UniversityNovosibirsk630090Russia Research and Development Department.Kemerovo State University Kemerovo650000Russia Laboratory of Crystal Physics Kirensky Institute of PhysicsFederal Research Center KSC SB RASKrasnoyarsk660036Russia Siberian Federal University Krasnoyarsk660041Russia Department of Physics Far Eastern State Transport UniversityKhabarovsk680021Russia Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing100190China Laboratory of Coherent Optics Kirensky Institute of Physics.Federal Research Center KSC SB RASKrasnoyarsk660036Russia Institute of Nanotechnology Spectroscopy and Quantum ChemistrySiberian Federal UniversityKrasnoyarsk660041Russia Laboratory of Molecular Spectroscopy Kirensky Institute of PhysicsFederal Research Center KSC SB RASKrasnoyarsk660036Russia Center for Materials Research(LaMa) Justus-Liebig-University GiessenGiessen35392Germany University of the Chinese Academy of Sciences Beijing100049China Laboratory of the Chemistry of Rare Earth Compounds Institute of Solid State ChemistryUB RASEkaterinburg620137Russia

A double holmium-silver sulfate was obtained for the first *** temperature intervals for the formation and stability of the compound were determined by differential scanning *** crystal structure of AgHo(SO_(4))_(2)was determined by Rietveld *** X-ray diffraction(XRD)analysis showed that the compound crystallizes in the monoclinic syngony,space group P2_1/m,with the unit cell parameters a=4.71751(4)A,b=6.84940(6)A and c=9.89528(9)A,β=95.1466(4)·,v=318.448(5)A^(3),Z=2,R_B=1.55%,T=303 *** types of sulfate tetrahedra were found in the structure,which significantly affected the spectral properties in the infrared *** the temperature range of 143-703 K,a negative thermal expansion along the b direction accompanied by a positive thermal expansion along the a and c directions was *** was established that negative thermal expansion is the result of the deformation of sulfate tetrahedra,which is affected by the movement of holmium and silver *** excitation in the blue spectral range(457.9 nm)produces a luminescence in light blue(489 nm),green(545 nm)and red(654 nm)spectral ranges,and the latter two were of comparable intensity that is favorable for WLED *** observed luminescent band distribution is ascribed to the specific crystal field at Ho^(3+)ion sites rather than a variation of radiationless probability.

关键词： Sulfate Crystal structure Thermal expansion Raman Photoluminescence Band structure