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Pyrrole and Pyrimidine Derivatives as Possible Electron Donors for Colored Charge-Transfer Complexes with a Weakly Electrophilic Energetic Material,FOX-7:A Theoretical Study

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火炸药学报 2023年第5期46卷 390-398,I0002-I0008页

作者： sergey v.Bondarchuk Department of Chemistry and Nanomaterials Science Bogdan Khmelnitsky Cherkasy National Universityblvd.Shevchenko 8118031 CherkasyUkraine

A number of electron-rich heterocycles are studied as potential reagents for visual colorimetric detection of FOX-7 due to colored charge-transfer complexes *** obtained results suggest that pyrrole and pyrimidine derivatives can form such complexes playing the role of electron donors despite a low electrophilicity of *** functional theory calculations,as well as quantum theory of atoms in molecules analysis,suggest stacking binding mode as the most preferable one with the binding energy of about 21-36 kJ/*** the complexes demonstrate a clear single charge-transfer absorption band in the visible region and the expected colors of the complexes are varying from violet and blue to red and *** calculations of the crystalline state of the studied complexes indicate high lattice energies,which are higher than that of pure FOX-7 and are close to the recently reported hydrogen-bonded complex of FOX-7 with 1,*** analysis of the studied charge-transfer complexes using properties based on density difference grids clearly suggests the acceptor role of FOX-7 in the *** analysis can be effectively applied to identify the nature of other possible complexes of FOX-7,in which its role is unclear because of the specific reactivity,namely,both weak electrophilic and nucleophilic properties at the same time.

关键词： FOX-7 charge-transfer colorimetric analysis detection of explosives quantum-chemical calculation

Protective Composite Coatings Formed on Mg Alloy Surface by PEO Using Organofluorine Materials

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Journal of Materials Science & Technology 2017年第7期33卷 661-667页

作者： Dmitry v. Mashtalyar Konstantine v. Nadaraia sergey L. Sinebryukhov sergey v. Gnedenkov Institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok 690022Russia Far Eastern Federal University Vladivostok 690950Russia

The results of the surface modification of magnesium alloys by plasma electrolytic oxidation（PEO） and subsequent treatment in suspension of the superdispersed polytetrafluoroethylene（SPTFE） or telomeric solution of tetrafluoroethylene（TFE） are presented. Composite coatings have been obtained by dipping with subsequent heat treatment. Electrochemical, tribological properties and wettability of protective composite coatings have been investigated. Composite coatings formed on PEO-layer by fourfold treatment of samples in SPTFE suspension possess best protective properties. The obtained coatings decrease the corrosion current density（5.4 × 10^（-11） A cm^（-2）） and wear（7.6 × 10^（-7）mm^3（Nm）^（-1））, and increase the polarisation resistance（1.7 × 10~9 cm^2） and impedance modulus（1.9 × 10~9 cm^2） by orders of magnitude in comparison with unprotected magnesium alloy and base PEO-coating. The highest value of contact angle（CA） has been obtained for coatings with triple application in telomeric solution. CA for such composite coatings attains（171 ± 2）？, as the result of multimodal roughness of the composite coating＇s surface.

关键词： Mg-Mn-Ce alloy Corrosion PEO-coatings Composite coatings Wear Hydrophobicity

Analysis of natural vibration of truncated conical shells partially filled with fluid

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International Journal of Mechanical System Dynamics 2024年第2期4卷 142-152页

作者： sergey A.Bochkarev sergey v.Lekomtsev Laboratory of Functional Materials Institute of Continuous Media MechanicsUral Branch of Russian Academy of SciencesPermRussian Federation

In this paper,we study the vibrational behavior of shells in the form of truncated cones containing an ideal compressible *** sloshing effect on the free surface of the fluid is *** dynamic behavior of the elastic structure is investigated based on the classical shell theory,the constitutive relations of which represent a system of ordinary differential equations written for new *** fluid vibrations are described in terms of acoustic approximation using the wave equation for hydrodynamic pressure written in spherical *** transformation into the system of ordinary differential equations is carried out by applying the generalized differential quadrature *** formulated boundary value problem is solved by Godunov's orthogonal sweep *** frequencies of shell vibrations are calculated using the stepwise procedure and the Muller *** accuracy and reliability of the obtained results are estimated by making a comparison with the known numerical and analytical *** dependencies of the lowest frequency on the fluid level and cone angle of shells under different combinations of boundary conditions(simply supported,rigidly clamped,and cantilevered shells)have been studied *** conical straight and inverted shells,a numerical analysis has been performed to estimate the possibility of finding configurations at which the lowest natural frequencies exceed the corresponding values of the equivalent cylindrical shell.

关键词： classical shell theory conical shell Godunov's orthogonal sweep method ideal compressible fluid generalized differential quadrature method natural vibrations

Flash Lamps as Ignition and Initiation Sources of the vS-2 Pyrotechnic Composition

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含能材料 2022年第4期30卷 370-378页

作者： sergey I.Gerasimov Mikhail A.Ilyushin sergey M.Putis sergey A.Dushenok Irina v.Shugalei Andrey M.Sudarikov Russian Federal Nuclear Center‑All‑Russian Research Institute of Experimental Physics SarovRussia Sarov Institute of Physics and Technology is a Branch of the Scientific Research Nuclear University MEPhI SarovRussia Nizhny Novgorod State Technical University Named after R.E.Alekseev Nizhny NovgorodRussia RAS Institute for Studying Problems in Mechanical Engineering ‑is a Branch of the RAS Applied Physics InstituteNizhny NovgorodRussia "Technologist"Special Design and Technological Bureau St.PetersburgRussia Saint‑Petersburg State Institute of Technology(Technical University) St.PetersburgRussia Russian State Hydro‑meteorological University St.PetersburgRussia

In the present work it is found that the pyrotechnic composition vS⁃2 can be initiated with flash lamps IFC⁃500 and ***⁃2 pyrotechnic composition contains 90%of mercury(Ⅱ)5⁃hydrazinotetrazolate perchlorate and 10%of optically trans⁃parent copolymer of 2⁃methyl⁃5⁃vinyltetrazole and methacrylic acid(PvMT).We have found that the flash lamps make it possi⁃ble to initiate combustion of vS⁃2 composition with its transition to detonation both in cylindrical charges placed in brass caps of 5 mm diameter and 2 mm high,and film charges with 10 mm×80 mm in size and surface weights of 60 mg·cm^(-2)and 90 mg·cm^(-2),showing ignition delay times 10μs and 3μs,*** also measured detonation velocities for vS⁃2 composition film charges,which were 4375-4505 m·s^(-1)(of the charge being surface mass 60 mg·cm^(-2))and 4221-4281 m·s^(-1)(of the charge be⁃ing surface mass 90 mg·cm^(-2))and their blasting action on the aluminum *** depths of the normal shock wave imprints at the charge⁃barrier interface were 0.6-0.7 mm(for surface mass of the film charges 60 mg·cm^(-2))and 1.2-1.3 mm(for surface mass of the film charges 90 mg·cm^(-2))

关键词： vS⁃2 pyrotechnic composition flash lamps ignition transition of combustion to detonation blasting action

Phase-matched third-harmonic generation via doubly resonant optical surface modes in 1D photonic crystals

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Light(Science & Applications) 2016年第1期5卷 424-429页

作者： valery N Konopsky Elena v Alieva sergey Yu Alyatkin Alexey A Melnikov sergey v Chekalin vladimir M Agranovich Institute of Spectroscopy Fizicheskaya5TroitskMoscow 142190Russia Moscow Institute of Physics and Technology Institutskiy per.9Dolgoprudny 141700Russia

Efficient nonlinear conversion requires that interacting optical waves maintain a consistent phase relationship when traveling in a medium despite its *** phase-matching,which is often used to compensate for the dispersion,is not applicable to optically isotropic nonlinear ***,we present a one-dimensional photonic crystal structure that allows the propagation of optical surface waves,both at the fundamental and third-harmonic frequencies,as an efficient medium for phasematched third-harmonic generation.A unique advantage of this structure is that the effective refractive indices for the surface waves are similar to the refractive index of air at both *** allows phase-matching between the first and third harmonics,and a visible collinear beam of the third harmonic is produced at the prism-coupled ***,these optical surface waves propagate over long distances even if a lossy nonlinear nanofilm is deposited onto the photonic crystal *** provide experimental results for third-harmonic generation at a wavelength of 410 nm for a bare dielectric Ta2O5/SiO2 multilayer structure and for the same structure coated with a 15-nm GaAs film.

关键词： nonlinear optics optical surface waves photonic crystals

Growth of carbon nanotube arrays on various CtxMey alloy films by chemical vapour deposition method

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Journal of Materials Science & Technology 2018年第3期34卷 472-480页

作者： Pawel Mierczynski sergey v.Dubkov sergey v.Bulyarskii Alexander A.Pavlov sergey N.Skorik Alexey Yu Trifonov Agnieszka Mierczynska Eugene P.Kitsyuk sergey A.Gavrilov Tomasz P.Maniecki Dmitry G.Gromov Institute of General and Ecological Chemistry Lodz University of TechnologyZeromskiego 116Lodz 90-924Poland National Research University of Electronic Technology Shokin SquareZelenogradMoscow 124498Russia Institute of Nanotechnology of Microelectronics of the RAS INMEMoscow 11-9991Russia Scientific-Manufacturing Complex'Technological Center' ZelenogradMoscow 124498Russia Scientific Research Institute of Physical Problems named after F v.Lukin Proezd 4806.6ZelenogradMoscow 124460Russia The Australian Wine Research Institute Waite PrecinctHartley Grove cnr Paratoo RoadUrrbrae AdelaideSA 5064Australia

Carbon nanotube （CNT） arrays were fabricated on Ct-Me-N-（O） alloys with content of Ct in the range of 6-40 at.% by chemical vapour deposition. The Ct was a catalytic metal from the group of the following elements： Ni, Co, Fe, Pd, while Me was a transition metal from the group of Iv-vII of the periodic table （where Me=Ti, v, Cr, Zr, Nb, Mo, Ta, W, Re）. Carbon nanotubes were found to grow efficiently on the alloy surface with its composition containing Ti, v, Cr, Zr, Hf, Nb or Ta. The growth of CNTs was not observed when the alloy contained W or Re. Additions of oxygen and nitrogen in the alloy facilitated the formation of oxynitrides and catalyst extrusion on the alloy surface. Replacement of the metals in alloy composition affected the diameter of the resulting CNTs. The obtained results showed that the alloy films of varying thickness （10-500 nm） may be used for the CNTs growth. The resulting CNT material was highly homogenous and its synthesis reproducible.

关键词： Carbon nanotubes Amorphous alloys Chemical vapour deposition Catalytic processes Thin films

BER Performance of Finite in Time Optimal FTN Signals for the viterbi Algorithm

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Journal of Electronic Science and Technology 2020年第1期18卷 42-51页

作者： sergey B.Makarov Ilya I.Lavrenyuk Anna S.Ovsyannikova sergey v.Zavjalov Higher School of Applied Physics and Space Technologies Peter the Great St.Petersburg Polytechnic UniversitySt.Petersburg 195251

In this article, we consider the faster than Nyquist(FTN) technology in aspects of the application of the viterbi algorithm(vA). Finite in time optimal FTN signals are used to provide a symbol rate higher than the "Nyquist barrier" without any encoding. These signals are obtained as the solutions of the corresponding optimization problem. Optimal signals are characterized by intersymbol interference(ISI). This fact leads to significant bit error rate(BER) performance degradation for "classical" forms of signals. However, ISI can be controlled by the restriction of the optimization problem. So we can use optimal signals in conditions of increased duration and an increased symbol rate without significant energy losses. The additional symbol rate increase leads to the increase of the reception algorithm complexity. We consider the application of vA for optimal FTN signals reception. The application of vA for receiving optimal FTN signals with increased duration provides close to the potential performance of BER,while the symbol rate is twice above the Nyquist limit.

关键词： Bit error rate(BER)performance faster than Nyquist(FTN) Nyquist limit optimal signals viterbi algorithm(vA)

Numerical and Experimental Investigation on Heat PropagationThrough Composite Sinter Bed With Non-Uniform voidage:Part Ⅱ Prediction of Process Efficiency

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Journal of Iron and Steel Research International 2010年第10期17卷 1-6页

作者： sergey v Komarov Hiroyuki Shibata Naohito Hayashi Eiki Kasai Nippon Light Metal Company Tohoku University

The results of numerical simulation of the mosaic embedding iron ore sintering （MEBIOS） process according to the model presented in the first part of the study are introduced. The main objective of the second part is the elucidation of key factors influencing the process efficiency, particularly the sintering completeness, velocity of the heat wave propagation and maximum temperature achievable in the pellet during the wave propagation. Numerical results reveal that the mass fraction of coal, diameter of coal particles and air inlet velocity are of prime importance in determining efficiency of the MEBIOS sintering process.

关键词： sintering MEBIOS process heat propagation mechanism numerical simulation process efficiency

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Fluctuating fine-scale spatial genetic structure in the common shrews (Eulipotyphla, Mammalia)

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Integrative Zoology 2023年第3期18卷 469-492页

作者： Nikolay A.SHCHIPANOv Artem v.ARTAMONOv sergey v.TITOv Svetlana v.PAvLOvA A.N.Severtsov Institute of Ecology and Evolution Russian Academy of SciencesMoscowRussia Department of Zoology and Ecology Penza State UniversityPenzaRussia

The spatial genetic structure is a topical issue in the studies of various aspects of ecology and *** the multilocus autocorrelation method with hypervariable microsatellite genetic markers,we investigated aﬁne-scale pattern of genetic structure in 5 local populations of the common shrew Sorex araneus separated by distances of 300–1000 m(the Moscow chromosomal race).Spatial genetic autocorrelation analysis based on 5 microsatellite loci(expected heterozygosity>0.79)with 90 alleles revealed a consistent pattern of signiﬁcant positive genetic *** testing the autocorrelation at multiple scales from 25 to 500 m,we found that positive spatial genetic structure is detectable in distance classes ofvely correlated with a higher ratio of nonresident individuals to residents’activity(number of captures).In contrast to nonresident animals,the residents demonstrated prominent genetic *** difference(FST)between the populations was signiﬁcant(0.016–0.051)and comparable with that between populations of different races analyzed previously(0.016–0.038).FST was not associated with geographic *** demographic patterns allowed us to propose a scheme of genetic-structure dynamics involving periodic appearance of more related local groups and renewal of allelic proﬁles fromаcommon pool where the alleles are *** scheme predictsﬂuctuating genetic structure and random similar differences among local populations.

关键词： demographic pattern geneﬂow microsatellite spatial autocorrelation