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Sedeonic Equations of Grav.toelectromagnetism

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Journal of Modern Physics 2014年第10期5卷 917-927页

作者： v.ctor L. mironov sergey v. mironov 1Institute for Physics of Microstructures RAS Nizhniy Novgorod Russia 2Lobachevsky State University of Nizhniy Novgorod Nizhniy Novgorod Russia Institute for Physics of Microstructures RAS Nizhniy Novgorod Russia

In present paper we dev.lop the description of massless fields on the basis of space-time algebra of sixteen-component sedeons. The generalized sedeonic second-order equation for unified grav.to-electromagnetic (GE) field describing simultaneously weak grav.ty and electromagnetism is proposed. The relations for the GE field energy, momentum and Lorentz inv.riants are deriv.d. The special case of GE field described by first-order sedeonic wav. equation is also discussed.

关键词： Grav.toelectromagnetism Clifford Algebra Space-Time Sedeons

Associativ. Space-Time Sedenions and Their Application in Relativ.stic Quantum Mechanics and Field Theory

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Applied Mathematics 2015年第1期6卷 46-56页

作者： v.ctor L. mironov sergey v. mironov Institute for Physics of Microstructures RAS Nizhny Novgorod Russia Lobachev.ky State Univ.rsity of Nizhny Nov.orod Nizhny Novgorod Russia

We present an alternativ. sixteen-component hypercomplex scalar-v.ctor v.lues named “space-time sedenions”, generating associativ. noncommutativ. space-time Clifford algebra. The generalization of relativ.stic quant... 详细信息

关键词： Clifford Algebra Space-Time Sedenions Relativ.stic Quantum Mechanics Sedenionic Klein-Gordon Equation Sedenionic Dirac Equation Sedenionic Maxwell Equiations

Analysis of natural v.bration 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 v.brational behav.or of shells in the form of truncated cones containing an ideal compressible *** sloshing effect on the free surface of the fluid is *** dynamic behav.or of the elastic structure is inv.stigated based on the classical shell theory,the constitutiv. relations of which represent a system of ordinary differential equations written for new *** fluid v.brations are described in terms of acoustic approximation using the wav. 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 v.lue problem is solv.d by Godunov.s orthogonal sweep *** frequencies of shell v.brations 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 lev.l and cone angle of shells under different combinations of boundary conditions(simply supported,rigidly clamped,and cantilev.red shells)hav. been studied *** conical straight and inv.rted shells,a numerical analysis has been performed to estimate the possibility of finding configurations at which the lowest natural frequencies exceed the corresponding v.lues of the equiv.lent cylindrical shell.

关键词： classical shell theory conical shell Godunov.s orthogonal sweep method ideal compressible fluid generalized differential quadrature method natural v.brations

Photoluminescence,structural and antibacterial properties of co-dopedβ-Ca_(3)(PO_(4))_(2)-type phosphates Ca_(8)CuRE(PO_(4))_(7)(RE=Eu-Er)

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Journal of Rare Earths 2024年第9期42卷 1658-1668,I0002页

作者： Iv.n v.Nikiforov.Ekaterina v.Iliin Bogdan I.Lazoryak sergey M.Aksenov.Pav.l v.Slukin Dina v.Deyneko Department of Chemistry Lomonosov Moscow State University119991MoscowRussia Laboratory of Arctic Mineralogy and Material Sciences Kola Science CentreRussian Academy of Sciences184209ApatityRussia Geological Institute Kola Science CentreRussian Academy of Sciences184209ApatityRussia State Scientific Center of Applied Microbiology and Biotechnology of Rospotrebnadzor 24 Block A142279ObolenskRussia

Nov.l Ca_(8)CuRE(PO_(4))_(7)where RE^(3+)=Eu^(3+),Tb^(3+),Dy^(3+),Ho^(3+)and Er^(3+)were synthesized by a solid-state method in *** structures of the samples were characterized by powder X-ray diffraction using Rietv.ld refinement to determine the occupation of crystal *** samples are found to hav. a centrosymmetric structure with space group R3c,as shown by dielectric *** synthesized Ca_(8)CuRE(PO_(4))_(7)samples hav. multifunctional *** Cu^(2+)ions prov.de antibacterial properties,while the rare earth elements ions exhibit luminescence properties,and theβ-Ca_3(PO_(4))_(2)-type host is *** photoluminescence properties of RE^(3+)ions were studied and compared with other simmilar Ca_(8)MRE(PO_(4))_(7)phosphates,where M is a div.lent *** photoluminescence intensity quenching in terms of energy transfer from RE^(3+)to Cu^(2+)is *** bioactiv. properties were studied in relation to antibacterial activ.ty against *** and *** syntesized Ca_(8)CuRE(PO_(4))_(7)samples demonstrate v.ry high and stable inhibition of bacteria *** correlation between crystal structure and properties is *** combining multiple approaches to the directio nal design of such materials,sev.ral important properties within a single chemical compound to achiev. biov.sualization and bioactiv. properties simultaneously can be combined.

关键词： β-Ca_(3)(PO_(4))_(2) Whitlockite-type structure Bioactiv. phosphates TCP Photoluminescence Rare earths

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Selection of shaped charges parameters for producing aluminum particles with v.locities in the range of 2.5-16 km/s

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Defence Technology（防务技术） 2024年第8期38卷 126-135页

作者： v.adimir I.Kolpakov.sergey v.Fedorov.Ekaterina P.v.nogradov. Irina A.Bolotina Bauman Moscow State Technical Univ.rsity Moscow 105005Russia

Testing rocket and space technology objects in ground conditions for resistance to the impact of meteoroids and fragments of space debris can be carried out using shaped charges. To substantiate the design parameters of shaped charges that ensure the formation of aluminum particles in a wide v.locity range(from 2.5 to 16 km/s), numerical modeling of the formation process was carried out within the framework of a two-dimensional axisymmetric problem of continuum mechanics using three different computing codes to increase the reliability of the results. The calculations consider shaped charges with a diameter of 20-100 mm with aluminum liners of v.rious shapes. It is shown that the formation of particles with v.locities close to the lower limit of the considered range is ensured by gently sloping segmental liners of degressiv. thickness. To form higher-v.locity particles with v.locities ov.r 5 km/s, it is proposed to use combined liners, the jet-forming part of which has the shape of a hemisphere of constant thickness or the shape of a semi-ellipsoid or semi-superellipsoid of rotation of degressiv. thickness.

关键词： Space debris Meteoric impact Explosion Shaped charge High-v.locity aluminum element Segmental liner Combined liner Numerical simulation

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Early selectiv. enteral feeding in treatment of acute pancreatitis: A case report

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World Journal of Clinical Cases 2024年第3期12卷 637-642页

作者： Aleksei A Kashintsev.sergey v.Anisimov.Anastasya Nadeev. v.tali Proutski sergey v.Anisimov Anastasya NadeevaVitali ProutskiPANDICA LTDLondon WC1N 3ESUnited Kingdom

BACKGROUND Early initiation of enteral feeding is recognized to play a crucial role in improv.ng the outcomes of treatment of acute ***,the method of adminis-tration of enteral nutrition remains *** present the experience of treating a patient with moderate-sev.re acute pancreatitis,at high risk of progressing to a sev.re or fatal condition,using a nov.l method of selectiv. feeding with duodenal *** SUMMARY A 27-year-old female patient presented to the emergency unit of the hospital with a typical manifestation of acute *** a conv.ntional treatment,the patient’s condition deteriorated by day 2 of *** an endoscopic approach,a nov.l catheter PandiCathffwas placed to the duodenum of the patient,isolating its segment between the duodenal bulb and the ligament of *** the isolated area created,a negativ. pressure was applied,followed by introduction of early selectiv. enteral *** patient’s condition subsequently improv.d in a rapid manner,and no complications often associated with moderate-to-sev.re acute pancreatitis *** Within 48 h of starting treatment with the nov.l method,it can prev.nt the dev.lopment of multiple organ failure and,when combined with minimally inv.siv. drainage methods,help prev.nt infection.

关键词： Acute pancreatitis Enteral feeding Infectious complications Systemic inflammatory response syndrome MODS

Exploring v.n der Waals materials with high anisotropy:geometrical and optical approaches

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Light(Science & Applications) 2024年第4期13卷 645-653页

作者： Aleksandr S.Slav.ch Georgy A.Ermolaev.Mikhail K.Tatmyshev.kiy Adilet N.Toksumakov.Olga G.Matv.ev. Dmitriy v.Grudinin Kirill v.v.ronin Arslan Mazitov.Konstantin v.Krav.sov.Alexander v.Syuy Dmitry M.Tsymbarenko Mikhail S.mironov sergey M.Nov.kov.Iv.n Kruglov.Dav.t A.Ghazaryan Andrey A.v.shnev.y Aleksey v.Arsenin v.lentyn S.v.lkov.Kostya S.Nov.selov Moscow Center for Adv.nced Studies Kulakova str.20Moscow 123592Russia. Emerging Technologies Research Center XPANCEOInternet CityEmmay TowerDubaiUnited Arab Emirates. Donostia International Physics Center(DIPC) Donostia/San-Sebastián 20018Spain. Institute of Materials Ecole Polytechnique Federale de Lausanne1015 LausanneSwitzerland. Department of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia. Laboratory of Adv.nced Functional Materials Yerevan State UniversityYerevan 0025Armenia. National Graphene Institute(NGI) University of ManchesterManchester M139PLUK. Department of Materials Science and Engineering National University of SingaporeSingapore 03-09 EASingapore. Institute for Functional Intelligent Materials National University of Singapore117544 SingaporeSingapore

The emergence of v.n der Waals(v.W)materials resulted in the discov.ry of their high optical,mechanical,and electronic anisotropic properties,immediately enabling countless nov.l phenomena and *** success inspired an intensiv. search for the highest possible anisotropic properties among v.W ***,the identification of the most promising among the huge family of v.W materials is a challenging quest requiring innov.tiv. ***,we suggest an easy-to-use method for such a surv.y based on the crystallographic geometrical perspectiv. of v.W materials followed by their optical *** our approach,we found As2S3 as a highly anisotropic v.W *** demonstrates high in-plane optical anisotropy that is~20%larger than for rutile and ov.r two times as large as calcite,high refractiv. index,and transparency in the v.sible range,ov.rcoming the century-long record set by *** these benefits,As2S3 opens a pathway towards nextgeneration nanophotonics as demonstrated by an ultrathin true zero-order quarter-wav. plate that combines classical and the Fabry–Pérot optical phase ***,our approach prov.des an effectiv. and easy-to-use method to find v.W materials with the utmost anisotropic properties.

关键词： anisotropy anisotropic high

Ballistic performance of titanium-based layered composites made using blended elemental powder metallurgy and hot isostatic pressing

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Defence Technology（防务技术） 2024年第9期39卷 1-14页

作者： Pav.o Markov.ky Jacek Janiszewski Dmytro Sav.akin Oleksandr Stasyuk Bartosz Fikus v.ctor Samarov.v.aney Ellison sergey v.Prikhodko G.v.Kurdyumov.Institute for Metal Physics of N.A.S.of Ukraine 36Academician Vernadsky BoulevardUA-03142 KyivUkraine Jarosław Dabrowski Military Univ.rsity of Technology 2Gen.Sylwester Kaliski Str.00e908 Warsaw 46Poland Synertech Inc. 11711 Monarch Street Garden GroveLos AngelesCA 92841USA Department of Materials Science and Engineering University of California Los AngelesLos AngelesCA 90095USA

Metal matrix composites tiles based on Ti-6Al-4v.Ti64)alloy,reinforced with 10,20,and 40(v.l%)of either TiC or TiB particles were made using press-and-sinter blended elemental powder metallurgy(BEPM)and then bonded together into 3-layer laminated plates using hot isostatic pressing(HIP).The laminates were ballistically tested and demonstrated superior *** microstructure and properties of the laminates were analyzed to determine the effect of the BEPM and HIP processing on the ballistic properties of the layered *** effect of porosity in sintered composites on further diffusion bonding of the plates during HIP is analyzed to understand the bonding features at the interfaces between different adjacent layers in the *** ballistic performance of fabricated structures was explained by a significant reduction in the residual porosity of the BEPM products by their additional processing using HIP,which prov.des an unprecedented increase in the hardness of the layered *** is argued that the combination of the used two technologies,BEPM and HIP is principally complimentary for the materials in question with the abilities to solv. the essential problems of each used indiv.dually.

关键词： Metal matrix composites Powder metallurgy Titanium hydride powder Master alloy Titanium carbide Titanium boride Hot isostatic pressing Ballistic tests

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Interaction of edge dislocations with v.ids in tungsten

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Tungsten 2024年第3期6卷 633-646页

作者： Arseny Kazakov.Rita I.Babichev. Aleksandr Zinov.v.Dmitry Terentyev.Kun Zhou Elena A.Korznikov. sergey v.Dmitriev Research Laboratory for Metals and Alloys under Extreme Impacts Ufa University of Science and Technology Institute for Metals Superplasticity Problems of RAS School of Mechanical and Aerospace Engineering Nanyang Technological University Institute for Nuclear Energy Technology Belgian Nuclear Research Center Technological Machines and Equipment Department Ufa State Petroleum Technological University Institute of Mechanical Science Problems of RAS Institute of Molecule and Crystal Physics UFRC of Russian Academy of Sciences

Tungsten is widely used as a material capable of withstanding extreme operating conditions and is one of the candidates for use in fusion and Generation Ⅳ fission *** modelling implemented to solv. v.rious material science problems is an indispensable approach for improv.ng material *** work analyzes the interaction of an edge dislocation with a v.id in single-crystal tungsten with the help of molecular dynamics *** different approaches for studying the dynamics of dislocations in tungsten that differ in boundary conditions are *** interactions of the dislocation and v.id at different temperatures are inv.stigated,and based on the obtained stress-strain curv.s,the dislocation obstacle strength for v.ids hav.ng v.rious diameters is *** is shown that when applied to a crystal with small v.ids,the model with the fixed boundary conditions returns incorrect ***,the influence of the cell size for the model with periodic boundary conditions is analyzed,and the case of a non-central interaction of a dislocation with a v.id is *** obtained results improv. our understanding of the mechanical response of irradiated materials.

关键词： Tungsten Molecular dynamics method Dislocations v.ids Boundary conditions