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Accounting for Quadratic and Cubic Invariants in Continuum Mechanics–An Overview

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Fluid Dynamics & Materials Processing 2024年第9期20卷 1925-1939页

作者： Artur v.Dmitrenko vladislav M.Ovsyannikov Department of Physics National Research Nuclear University(MEPhI)Kashirskoye Shosse 31Moscow115409Russian Federation Department of Thermal Engineering and Department of Waterways Ports and Hydraulic StructuresRussian University of Transport(MIIT)Obraztsova Street 9Moscow127994Russian Federation

The differential equations of continuum mechanics are the basis of an uncountable variety of phenomena and technological processes in fluid-dynamics and related *** equations contain derivatives of the first order with respect to *** derivation of the equations of continuum mechanics uses the limit transitions of the tendency of the volume increment and the time increment to *** are used to derive the wave *** differential wave equation is second order in ***,increments of volume and increments of time in continuum mechanics should be considered as small but finite quantities for problems of wave *** is important for calculating the generation of sound waves and water hammer ***,the Euler continuity equation with finite time increments is of *** finiteness of the time increment makes it possible to take into account the quadratic and cubic invariants of the strain rate *** is a new branch in *** and cubic invariants will be used in differential wave equations of the second and third order in time.

关键词： Quadratic invariant cubic invariant continuity equation generation of periodic waves N.E.Zhukovsky’s hydraulic shock turbulence

Elucidating elusive quaternary selenide EuCeCuSe3:Synthesis,crystal structure,properties and theoretical studies

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Journal of Rare Earths 2024年第1期42卷 163-171,I0006页

作者： Maxim v.Grigoriev Anna v.Ruseikina Maxim S.Molokeev vladimir A.Chernyshev Aleksandr S.Aleksandrovsky Alexander S.Krylov Svetlana N.Krylova Nikolai P.Shestakov Dmitriy A.velikanov Alexander A.Garmonov Alexey v.Matigorov Evgeny A.Ostapchuk Thomas Schleid Damir A.Safin Laboratory of Theory and Optimization of Chemical and Technological Processes University of TyumenVolodarskogo Str.6625003TyumenRussian Federation Kirensky Institute of Physics Federal Research Center KSC SB RASAkademgorodok 50 Bld.38660036KrasnoyarskRussian Federation Department of Physics Far Eastern State Transport UniversitySerysheva Str.47680021KrasnoyarskRussian Federation Institute of Natural Sciences and Mathematics Ural Federal University Named After the First President of Russia B.N.YeltsinMira Str.19620002EkaterinburgRussian Federation Department of Photonics and Laser Technology Siberian Federal UniversitySvobodnii Ave.79660079KrasnoyarskRussian Federation Institute of Physics and Technology University of TyumenVolodarskogo Str.6625003 TyumenRussian Federation Institute for Inorganic Chemistry University of StuttgartPfaffenwaldring 55D-70569StuttgartGermany Scientific and Educational and Innovation Center for Chemical and Pharmaceutical Technologies Ural Federal University named after the First President of Russia B.N.YeltsinMira Str.19620002 EkaterinburgRussian Federation University of Tyumen Volodarskogo Str.6625003TyumenRussian Federation

We report on the novel heterometallic quaternary selenide EuCeCuSe3,the fabrication of which has been a challenge until this *** structure of the reported selenide was elucidated from the powder X-ray diffraction data,which revealed the formation of EuCeCuSe3with excellent yield(96.7%)accompanied with a minor fraction of CeSe2(3.3%),and was best solved in orthorhombic space group Pnma with the BaLaCuS3structural ***,the crystal structure of the title compound completes the row of the heterometallic quaternary selenides EuRECuSe3(RE=La,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Y),of which the cerium-based derivative exclusively belongs to the BaLaCuS3structural *** distortion of the CuSe4polyhedron was compared for the whole series of EuRECuSe3compounds using theτ4-descriptor for four coordinated ions,which revealed the highest degree of distortion for the Ce3+-containing selenide,followed by the La3+-based ***,the crystallographic and geometrical parameters of the reported selenide were discussed in comparison to the Ce3+-based sulfides SrCeCuS3and *** initio calculations of the crystal structure,a phonon spectrum and elastic constants for the crystal of EuCeCuSe3were also *** types and wavenumbers of fundame ntal modes were determined and the involvement of ions participating in the phonon modes was *** experimental IR spectrum of the reported selenide was interpreted and found to be in agreement with the calculated *** experimental direct band gap of EuCeCuSe3was measured to be 1.36 ev that is consistent with the concept of its origin due to interband transitions between orbitals emerging mainly from 4f(valence band)and 5d(conduction band)levels of the Eu2+*** dependence of the Young’s modulus on the direction demonstrates the anisotropy of the elastic properties,while the vickers hardness for EuCeCuSe3was calculated to be 5.2 ***,the title compound is paramagnetic above 4 K.

关键词： Quaternary selenide Synthesis Crystal structure Ab initio calculations Magnetic measurements Spectroscopy

Myelin histology:a key tool in nervous system research

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Neural Regeneration Research 2024年第2期19卷 277-281页

作者： Óscar Darío García-García víctor Carriel Jesús Chato-Astrain Department of Histology Tissue Engineering GroupUniversity of Granada&Instituto de Investigación Biosanitaria ibs.GRANADAGranadaSpain

The myelin sheath is a lipoprotein-rich,multilayered structure capable of increasing conduction velocity in central and peripheral myelinated nerve *** to the complex structure and composition of myelin,various histological techniques have been developed over the centuries to evaluate myelin under normal,pathological or experimental ***,methods to assess myelin integrity or content are key tools in both clinical diagnosis and neuroscience *** this review,we provide an updated summary of the composition and structure of the myelin sheath and discuss some histological procedures,from tissue fixation and processing techniques to the most used and practical myelin histological staining *** the lipoprotein nature of myelin,the main features and technical details of the different available methods that can be used to evaluate the lipid or protein components of myelin are described,as well as the precise ultrastructural techniques.

关键词： fluorescence microscopy histology light microscopy lipid histochemistry metallographic techniques myelin histochemistry myelin immunohistochemistry myelin structure&composition myelin ultrastructural evaluation tissue fixation&processing

Porous Shish-Kebab Structure Prepared from Oriented UHMWPE Films by Processing in Supercritical CO_(2)

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Chinese Journal of Polymer Science 2024年第1期42卷 97-104,I0009页

作者： Sergey A.Lermontov Aleksey v.Maksimkin Nataliya A.Sipyagina Tarek Dayyoub Alena N.Malkova Evgeniy A.Kolesnikov Elena A.Straumal Inna O.Gozhikova Saidkhodzha G.Nematulloev Dmitry v.Telyshev Institute of Physiologically Active Compounds of the Russian Academy of Sciences Chernogolovka 142432Russia Institute for Bionic Technologies and Engineering I.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow 19991Russia National University of Science and Technology"MISIS"Moscow 119049 Russia Institute of Biomedical Systems National Research University of Electronic TechnologyZelenogradMoscow 124498Russia

For the first time, a highly crystalline porous shish-kebab structure with a high degree of crystallinity was obtained by using a combination of two methods for the formation of porous polymeric materials. A treatment procedure using supercritical carbon dioxide(sc CO_(2))was carried out for oriented ultrahigh molecular weight polyethylene(UHMWPE) films, which provided special conditions for the crystallization of dissolved UHMWPE macromolecules on the surface of oriented UHMWPE crystals. The prepared porous materials were investigated by scanning electron microscopy(SEM) and differential scanning calorimetry(DSC). The particularity of the obtained porous shish-kebab is the absence of the amorphous phase between lamellar crystals(kebabs). The obtained pores had an oval shape, and they were oriented in the orientation direction of the UHMWPE macromolecules. The pore size ranged from 0.05 μm to 4 μm. Controlling the conditions for the crystallization of the UHMWPE macromolecules using supercritical CO_(2) gives the possibility to control the size of both lamellar disks and pores formed.

关键词： UHMWPE Supercritical CO_(2) Porous shish-kebab structure

RBC aggregation, deformation and adhesion to endothelium: Role of nitric oxide derived from L-Arginine and sodium nitroprusside

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JOURNAL OF INNOvATIvE OPTICAL HEALTH SCIENCES 2024年第5期17卷 53-65页

作者： Maksimov, M. K. Ermolinskiy, P. B. Scheglovitova, O. N. Sklyankina, N. N. Muravyov, A. v. Lugovtsov, A. E. Priezzhev, A. v. Moscow Mv Lomonosov State Univ Fac Phys bld1Subbldg 2 Leninskie gory Moscow 11991 Russia NF Gamaleya Natl Res Ctr Epidemiol & Microbiol 18 Gamaleya St Moscow 123098 Russia KD Ushinsky Yaroslavl State Pedag Univ 108-1 Respublikanskaya St Yaroslavl 150000 Russia

Red blood cells (RBCs) are the most abundant human blood cells. RBC aggregation and deformation strongly determine blood viscosity which impacts hemorheology and microcirculation. In turn, RBC properties depend on different endogenous and exogenous factors. One such factor is nitric oxide (NO), which is mainly produced by endothelial cells (EC) from L-arginine amino acid in the circulatory system. Since the mechanisms of the RBC-endothelium interplay are not clear up to date and considering its possible clinical importance, the aims of this study are to investigate in vitro: (1) The effect of L-arginine induced NO on RBC aggregation and adhesion to endothelium; (2) the NO effect on RBC aggregation and deformation induced by L-arginine and sodium nitroprusside without the presence of endothelium in the samples. The RBC aggregation and adhesion to a monolayer of EC were studied using optical tweezers (OT). The RBC deformability and aggregation without endothelium in the samples were studied using the flow chamber method and Myrenne aggregometer. We confirmed that NO increases deformability and decreases aggregation of RBCs. We showed that the soluble guanylate cyclase pathway appears to be the only NO signaling pathway involved. In the samples with the endothelium, the "bell-shaped" dependence of RBC aggregation force on L-arginine concentration was observed, which improves our knowledge about the process of NO production by endothelium. Additionally, data related to L-arginine accumulation by endothelium were obtained: Necessity of the presence of extracellular L-arginine stated by other authors was put under question. In our study, NO decreased the RBC-endothelium adhesion, however, the tendency appeared to be weak and was not confirmed in another set of experiments. To our knowledge, this is the first attempt to measure the forces of RBC adhesion to endothelium monolayer with OT.

关键词： Red blood cells aggregation L-arginine endothelium optical tweezers Myrenne flow chamber RED-BLOOD-CELL vASCULAR ENDOTHELIUM SICKLE ERYTHROCYTES SHEAR-STRESS DEFORMABILITY ADHERENCE PROSTACYCLIN ELASTICITY MECHANISM STORAGE

SANC Monte Carlo programs for small-angle Bhabha scattering

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Chinese Physics C 2024年第4期48卷 14-19页

作者： A.B.Arbuzov S.G.Bondarenko I.R.Boyko L.v.Kalinovskaya A.A.Kampf R.R.Sadykov v.L.Yermolchyk Bogoliubov Laboratory of Theoretical Physics JINRDubna141980 Russia Dzhelepov Laboratory of Nuclear Problems JINRDubna141980 Russia Dubna State University Dubna141982 Russia

Luminosity monitoring at e^(+)e^(−)colliders was investigated using SANC Monte Carlo event generator ReneSANCe and integrator MCSANC for simulation of Bhabha scattering at low *** are presented for center-of-mass energies of the Z boson resonance and at 240 Gev for the conditions of typical luminosity *** is shown that bremsstrahlung events with extremely low electron scattering angles are relevant to match the precision tags of future electron-positron colliders.

关键词： luminosity Bhabha scattering QED Monte Carlo simulation

Polariton lasing in Mie-resonant perovskite nanocavity

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Opto-Electronic Advances 2024年第4期7卷 27-42页

作者： Mikhail A.Masharin Daria Khmelevskaia valeriy I.Kondratiev Daria I.Markina Anton D.Utyushev Dmitriy M.Dolgintsev Alexey D.Dmitriev vanik A.Shahnazaryan Anatoly P.Pushkarev Furkan Isik Ivan v.Iorsh Ivan A.Shelykh Hilmi v.Demir Anton K.Samusev Sergey v.Makarov UNAM-Institute of Materials Science and Nanotechnology National Nanotechnology Research CenterDepartment of Electrical and Electronics EngineeringDepartment of PhysicsBilkent UniversityAnkara 06800Turkey ITMO University School of Physics and EngineeringSt.Petersburg 197101Russia Abrikosov Center for Theoretical Physics MIPTDolgoprudnyiMoscow Region 141701Russia LUMINOUS!Center of Excellence for Semiconductor Lighting and Displays School of Electrical and Electronic EngineeringSchool of Physical and Mathematical SciencesSchool of Materials Science and EngineeringNanyang Technological UniversitySingapore 639798Singapore Department of Physics Engineering Physics and AstronomyQueen’s UniversityKingstonOntario K7L 3N6Canada Science Institute University of IcelandDunhagi 3IS-107ReykjavikIceland Experimentelle Physik 2 Technische Universität DortmundDortmund 44227Germany Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao 266000China

Deeply subwavelength lasers(or nanolasers)are highly demanded for compact on-chip bioimaging and sensing at the *** of the main obstacles for the development of single-particle nanolasers with all three dimensions shorter than the emitting wavelength in the visible range is the high lasing thresholds and the resulting *** we ex-ploit exciton-polariton condensation and mirror-image Mie modes in a cuboid CsPbBr3 nanoparticle to achieve coherent emission at the visible wavelength of around 0.53μm from its ultra-small(≈0.007μm3 or≈λ3/20)semiconductor *** polaritonic nature of the emission from the nanocavity localized in all three dimensions is proven by direct com-parison with corresponding one-dimensional and two-dimensional waveguiding systems with similar material *** a deeply subwavelength nanolaser is enabled not only by the high values for exciton binding energy(≈35 mev),re-fractive index(>2.5 at low temperature),and luminescence quantum yield of CsPbBr3,but also by the optimization of po-laritons condensation on the Mie resonances with quality factors improved by the metallic ***,the key parameters for optimal lasing conditions are intermode free spectral range and phonons spectrum in CsPbBr3,which govern polaritons condensation *** chemically synthesized colloidal CsPbBr3 nanolasers can be potentially de-posited on arbitrary surfaces,which makes them a versatile tool for integration with various on-chip systems.

关键词： nanolaser perovskite polariton Mie resonance exciton-polariton

Selection of shaped charges parameters for producing aluminum particles with velocities 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： vladimir I.Kolpakov Sergey v.Fedorov Ekaterina P.vinogradova Irina A.Bolotina Bauman Moscow State Technical University 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 velocity 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 various shapes. It is shown that the formation of particles with velocities close to the lower limit of the considered range is ensured by gently sloping segmental liners of degressive thickness. To form higher-velocity particles with velocities over 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 degressive thickness.

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

Comparing the Structural Parameters of the Milky Way to Other Spiral Galaxies

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Research in Astronomy and Astrophysics 2024年第3期24卷 10-28页

作者： Jacob A.Guerrette Aleksandr v.Mosenkov Dallin Spencer Zacory D.Shakespear Department of Physics and AstronomyN283 ESCBrigham Young University ProvoUT 84602USA

The structural parameters of a galaxy can be used to gain insight into its formation and evolution *** this paper,we strive to compare the Milky Way’s structural parameters to other,primarily edge-on,spiral galaxies in order to determine how our Galaxy measures up to the Local *** our comparison,we use the galaxy structural parameters gathered from a variety of literature sources in the optical and near-infrared wave *** compare the scale length,scale height,and disk flatness for both the thin and thick disks,the thick-to-thin disk mass ratio,the bulge-to-total luminosity ratio,and the mean pitch angle of the Milky Way’s spiral arms to those in other *** conclude that many of the Milky Way’s structural parameters are largely ordinary and typical of spiral galaxies in the Local Universe,though the Galaxy’s thick disk appears to be appreciably thinner and less extended than expected from zoom-in cosmological simulations of Milky Way-mass galaxies with a significant contribution of galaxy mergers involving satellite galaxies.

关键词： Galaxy disk-galaxies fundamental parameters-Galaxy structure