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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

ENSO Index variations and Links with Solar and volcanic Activity

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Natural Science 2024年第4期16卷 25-44页

作者： valentina v. Zharkova irina vasilieva Department of MPEE Faculty of Engineering and Environment University of Northumbria Newcastle upon Tyne NE UK ZvS Research Enterprise Ltd. London UK Department of Solar Physics Main Astronomical Observatory Kyiv Ukraine

In this paper, we investigated the Oceanic Niño Index (ONI), for simplicity called in this paper an El Nino Southern Oscillation (ENSO) index in 1950-2023 by applying the wavelet spectral transform and the IBM SPSS correlations analysis. ONI follows the three months’ current measurements of the average temperature of the sea surface in the East-Central tropical part of the Pacific Ocean nearby the international line of the date change over the average sea surface temperature over the past 30 years. The ENSO index is found to have a strong (>87%) correlation with the Global Land-Ocean Temperature (GLOT). The scatter plots of the ENSO-GLOT correlation with the linear and cubic fits have shown that the ENSO index is better fit by the cubic polynomial increasing proportionally to a cubic power of the GLOT variations. The wavelet analysis allowed us to detect the two key periods in the ENSO (ONI) index: 4 - 5 years and 12 years. The smaller period of 4.5 years can be linked to the motion of tectonic plates while the larger period of 12 years is shown to have a noticeable correlation of 25% with frequencies of the underwater (submarine) volcanic eruptions in the areas with ENSO occurrences. Not withholding any local terrestrial factors considered to contribute to the ENSO occurrences, we investigated the possibility of the volcanic eruptions causing ENSO to be also induced by the tidal forces of Jupiter and Sun showing the correlation of the underwater volcanic eruption frequency with the Jupiter-Earth distances to be 12% and with the Sun-Earth distances, induced by the solar inertial motion, in January, when the Earth is turned to the Sun with the southern hemisphere where the ENSO occurs, to become 15%. Hence, the underwater volcanic eruptions induced by tidal forces of Jupiter and Sun can be the essential additional factors imposing this 12 year period of the ENSO (ONI) index variations.

关键词： Sun: Magnetic Field Sun: Solar Activity Sun: Inertial Motion Earth: Temperature Earth: Sea Level Earth: Ice Area

Effect of sodium nitroprusside on the microrheological properties of red blood cells in di®erent media

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 23-31页

作者： Petr Ermolinskiy Matvey Maksimov Andrei Lugovtsov Alexey Muravyov irina Tikhomirova Alexander Priezzhev Faculty of Physics M.V.Lomonosov Moscow State University Moscow 119991Russia Faculty of Physical Education K.D.Ushinsky Yaroslavl State Pedagogical University Yaroslavl 150000 Russia Faculty of Natural Sciences K.D.Ushinsky Yaroslavl State Pedagogical University Yaroslavl 150000 Russia

Red blood cell(RBC)aggregation as well as their deformation signi¯cantly affects blood *** processes depend on various factors,one of which is concentration of the nitric oxide,one of the main signaling molecule in the *** purpose of this study was to investigate the effect of nitric oxide on the microrheological properties of red blood cells(RBCs)in RBC samples of various media after the addition of nitric oxide donor sodium nitroprusside in *** properties were measured using laser aggregometer and ektacytometer based on diffuse light scattering and diffraction of laser light on a suspension of RBCs,*** study found that heparin-stabilized blood showed increased RBC aggregation and deformation with sodium nitroprusside concentrations of 100,and 200M,while EDTA-stabilized blood showed slightly decreased aggregation and unchanged *** washed RBCs in dextran solution,the addition of sodium nitroprusside(in the concentrations of 100,and 200M)resulted in decreased aggregation and increased ***-ndings aid in our understanding of nitric oxide's effect on RBC microrheological properties.

关键词： Sodium nitroprusside nitric oxide red blood cells RBC aggregation diffuse light scattering laser diffractometer

Water Photomolecular Evaporation Due to Light-Mediated Ortho-Para Spin Transitions

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Open Journal of Applied Sciences 2024年第8期14卷 2201-2206页

作者： Sergey Pershin irina Bjørnø Michael Grishin Prokhorov General Physics Institute of the Russian Academy of Sciences Moscow Russia RKMD Copenhagen Denmark

Recent discoveries have revealed a groundbreaking phenomenon where light alone, without any thermal input, can induce water evaporation, termed the “photomolecular effect”. This study explores a novel hypothesis that this effect can be explained by ortho-para magnetic spin interactions in water molecules within the water-air interface layer. Water molecules, consisting of hydrogen and oxygen, exhibit different nuclear spin states: ortho-(triplet) and para-(singlet). The interaction of polarized light with these spin states may induce transitions between the rotational levels of ortho- and para-forms due to catalysts like triplet oxygen (O2) in its inhomogeneous magnetic field. Resonance pumping at 532 nm (~18,797 cm−1) due to the transition v1-v2-v3 ~ 0-8-2 (~18,796 cm−1) results in an increase in molecular energy sufficient to overcome intermolecular forces at the water surface, thereby causing evaporation. The proposed ortho-para conversion mechanism involves spin-orbit coupling and specific resonance conditions. This theory provides a quantum mechanical perspective on the photomolecular effect, potentially offering insights into natural processes such as cloud formation and climate modeling, as well as practical applications in solar desalination and industrial drying. Further experimental validation is required to confirm the role of spin interactions in light-induced water evaporation.

关键词： Ortho-Para Spin Transition Water Structure Evaporation Theory Photo Molecular Effect

Gut Microbiota and Cytokine Profile in Cirrhosis

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Journal of Clinical and Translational Hepatology 2024年第8期12卷 689-700页

作者： irina Efremova Roman Maslennikov Anna Kudryavtseva Anastasia Avdeeva George Krasnov Mikhail Diatroptov vyacheslav Bakhitov Salekh Aliev Natalia Sedova Maria Fedorova Elena Poluektova Oxana Zolnikova Nariman Aliev Anna Levshina vladimir Ivashkin Department of Internal Medicine Gastroenterology and HepatologySechenov UniversityMoscowRussia Post-Genomic Research Laboratory Engelhardt Institute of Molecular BiologyRussian Academy of SciencesMoscowRussia v.A.Nasonova Research Institute of Rheumatology MoscowRussia Consultative and Diagnostic Center 2 of the Moscow Health Department MoscowRussia First Hospital Surgery Department Pirogov Russian National Research Medical UniversityMoscowRussia Department of Clinical Laboratory Diagnostics FGBOU DPO“Russian Medical Academy of Continuing Professional Education of the Ministry of Health of the Russian Federation”MoscowRussia The Interregional Public Organization“Scientific Community for the Promotion of the Clinical Study” MoscowRussia

Background and Aims:Gut dysbiosis and abnormal cytokine profiles are common in *** study aimed to evaluate the correlations between ***:In the blood plasma of cirrhosis patients and controls,27 cytokines were examined using a multiplex *** plasma levels of nitrites(stable metabolites of the endothelial dysfunction biomarker nitric oxide)and lipopolysaccharide(LPS)were *** fecal microbiota was assessed by 16S rRNA gene ***:Levels of IL-1b,IL-2,IL-6,IL-13,IP-10,IFN-g,TNF-a,LPS,and nitrites were higher in cirrhosis patients than in controls,while levels of IL-4,IL-7,and PDGF-BB were *** LPS level was directly correlated with the levels of IL-1b,IL1-Ra,IL-9,IL-17,PDGF-BB,IL-6,TNF-a,and *** nitrite level was significantly directly correlated with the levels of TNF-a,GM-CSF,IL-17,and IL-12,and inversely correlated with the IL-7 ***-a levels were directly correlated with ascites severity and the abundance of Negativicutes,Enterobacteriaceae,veillonellaceae,and Klebsiella,while inversely correlated with the abundance of Firmicutes,Clostridia,and ***-g levels were directly correlated with the abundance of Bacteroidaceae,Lactobacillaceae,Bacteroides,and Megasphaera,and inversely correlated with the abundance of verrucomicrobiota,Akkermansiaceae,Coriobacteriaceae,Akkermansia,Collinsella,and ***-1b levels were directly correlated with the abundance of Comamonadaceae and Enterobacteriaceae and inversely correlated with the abundance of Marinifilaceae and ***-6 levels were directly correlated with the abundance of Enterobacteriaceae,hepatic encephalopathy,and ascites severity,and inversely correlated with the abundance of Peptostreptococcaceae,Streptococcaceae,and ***:The abundance of harmful gut microbiota taxa and endotoxinemia directly correlates with the levels of proinflammatory cytokines.

关键词： Endotoxin Leaky gut Gut microbiome Systemic inflammation Gut-liver axis Endotoxemia

Novel method for the preparation of Cs-containing FAU（Y） catalysts for aniline methylation

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Frontiers of Chemical Science and Engineering 2018年第1期12卷 70-76页

作者： Olga A. ponomareva Polina A. Shaposhnik Marina vo Belova Boris A. Kolozhvari irina I. Ivanova Department of Chemistry Lomonosov Moscow State University Moscow 119991 Russia A.v. Topchiev Institute of Petrochemical Synthesis Moscow Russia

Cs-containing FAU（Y）-type zeolite catalysts were prepared by conventional and novel ion exchange procedures followed by incipient wetness impregnation with CsOH. The novel ion exchange procedure involved hydrothermal treatment of NaY zeolite in aqueous solution of CsCl at 140-200 ℃ for 6-24 h. The samples were characterized by low-temperature nitrogen adsorption, X-ray fluorescence analysis, X-ray powder diffraction, scanning electron microscopy, 23Na, 27Al and 133Cs magic angle spinning nuclear magnetic resonance, CO2 and NH3-Temperature programmed desorption. The results show that hydrothermal treatment at 200 ℃ allows to obtain higher degrees of ion-exchange （up to 83%） with respect to conventional method giving maximum 66%- 69%. Catalytic properties of Cs-containing FAU（Y） were studied in aniline methylation. The yield of Nomethylani- line is shown to correlate with catalyst＇s basicity. The best catalyst performance was achieved over the catalyst with the highest ion-exchange degree impregnated with CsOH. The selectivity to N-methylaniline over this catalyst reached 96.4%.

关键词： FAU(Y) zeolite ion exchange with cesium aniline alkylation N-methylaniline

Investigation of electrophysical, photo- and gas-sensitive properties of ZnO–SnO_(2) sol–gel fflms

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Journal of Advanced Dielectrics 2024年第1期14卷 42-50页

作者： irina A.Gulyaeva Alexandra P.Ivanisheva Maria G.volkova victoria Yu.Storozhenko Soslan A.Khubezhov Ekaterina M.Bayan victor v.Petrov Research and Education Centre“Microsystem Technics and Multisensory Monitoring Systems”Southern Federal University Russia Department of Chemistry Southern Federal UniversityRussia Department of Physics North-Ossetian State University362025 VladikavkazRussia Department of Physics and Engineering ITMO University191002 PetersburgRussia

Thin nanocomposite fflms based on tin dioxide with a low content of zinc oxide(0.5–5 mol.%)were obtained by the sol–gel *** synthesized fflms are 300–600 nm thick and contains pore sizes of 19–29 *** resulting ZnO–SnO_(2) fflms were comprehensively studied by atomic force and Kelvin probe force microscopy,X-ray diffraction,scanning electron microscopy,and high-resolution X-ray photoelectron spectroscopy *** photoconductivity parameters on exposure to light with a wavelength of 470 nm were also *** study of the photosensitivity kinetics of ZnO–SnO_(2) fflms showed that the fflm with the Zn:Sn ratio equal to 0.5:99.5 has the minimum value of the charge carrier generation time *** of the activation energy of the conductivity,potential barrier,and surface potential of ZnO–SnO_(2) fflms showed that these parameters have maxima at ZnO concentrations of 0.5 mol.%and 1 mol.%.Films with 1 mol.%ZnO exhibit high response values when exposed to 5–50 ppm of nitrogen dioxide at operating temperatures of 200℃ and 250℃.

关键词： Sol–gel method,ZnO–SnO_(2) films gas-sensitive properties surface potential potential barrier conduction activation energy

First Asian record of Panthera(Leo)fossilis(Mammalia,Carnivora,Felidae)in the Early Pleistocene of Western Siberia,Russia

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Integrative Zoology 2014年第4期9卷 517-530页

作者： Marina v.SOTNIKOvA irina v.FORONOvA Geological Institute of Russian Academy of Sciences MoscowRussia v.S.Sobolev Institute of Geology and Mineralogy Siberian Branch of Russian Academy of SciencesNovosibirskRussia

A lion-like pantherine felid is described as Panthera(Leo)fossilis from the late Early Pleistocene sediments of the Kuznetsk Basin(Western Siberia,Russia).The find of *** first recorded in Asia considerably extends the current notion of the eastward expansion of the most ancient *** Siberian lion is geologically the oldest form and is dimensionally among the largest members of the group of fossil lions on the Eurasian conti*** known by mandibular remains only,it is readily distinguished from Panthera(Leo)spelaea by a heavy built mandibular corpus with rectangular profile in the cheek teeth area,a deep,well-outlined and narrow anterior section of the masseteric fossa,and a largeр4 supported by a big unreduced anterior *** Siberian lion shares these features with the European Middle Pleistocene *** and the American Late Pleistocene P.(Leo)atrox,which suggests their close *** originated from *** and was isolated in North America south of the Late Pleistocene ice *** explains why the American lion has retained more primitive features than the coeval Eurasian cave lion P.(L.)spelaea.

关键词： Early Pleistocene evolution Panthera fossilis relationships Western Siberia

Studying the direction of hydraulic fracture in carbonate reservoirs:Using machine learning to determine reservoir pressure

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Petroleum Research 2023年第2期8卷 226-233页

作者： Dmitriy A.Martyushev Inna N.ponomareva Evgenii v.Filippov Department of Oil and Gas Technologies Perm National Research Polytechnic UniversityPerm614990Russia Department of Oil and Gas Fields Development LLC《LUKOIL-PERM》Perm614068Russia

Hydraulic fracturing(HF)is an effective way to intensify oil production,which is currently widely used in various conditions,including complex carbonate *** the conditions of the field under consideration,the hydraulic fracturing leads to a significant differentiation of technological efficiency indicators,which makes it expedient to study the patterns of crack formation in *** were carried out for all wells,which were considered as the objects of impact,to assess the spatial orientation of the cracks *** developed indirect method was used for this purpose,the reliability of which was confirmed by geophysical *** the analysis,it was found that in all cases,the crack is oriented in the direction of the section of the development system element characterized by the maximum reservoir *** the same time,the reservoir pressure values for all wells were determined at one point in time(at the beginning of HF)using machine learning *** reliability of the machine learning methods used is confirmed by the high convergence with the actual(historical)reservoir pressures obtained during hydrodynamic studies of *** obtained conclusion about the influence of the reservoir pressure on the patterns of fracture formation should be taken into account when planning hydraulic fracturing under the conditions studied.

关键词： Hydraulic fracturing direction Machine learning Actual field data Correlation coefficient Well flow rate Well geophysical studies Carbonate reservoir