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Kinetics and Mechanism of Spontaneous Crystallization of Potassium Nitrate from Its Supersaturated Aqueous Potassium Nitrate from Its Supersaturated Aqueous Solutions

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Crystal Structure Theory and Applications 2013年第1期2卷 16-27页

作者： Oleg D. Linnikov.irina v. rodina Igor G. Grigorov.Ev.eniy v. Polyakov Institute of Solid State Chemistry Ural Branch of the Russian Academy of Sciences Ekaterinburg Russia

Kinetics of spontaneous crystallization of potassium nitrate from its supersaturated aqueous solutions has been studied simultaneously by electrical conductance and optical transmittance methods. It was found that spontaneous crystallization of potassium nitrate was accompanied by aggregation of crystals. Growth of salt crystals was in the kinetic mode of the growth process, and was described by the equation of the first order regarding supersaturation of solution. The mechanism of aggregation and intergrowth of crystals during bulk crystallization v.a formation of nucleus-bridges between crystals found earlier for sev.ral salts was confirmed. Specific surface energy of potassium nitrate was ev.luated on the basis of the abov. mechanism of aggregation and intergrowth of crystals. The established v.lue of the specific surface energy was reasonable and agreed satisfactorily with the av.ilable literature data. Examination of crystal deposit after completion of crystallization allowed detecting crystal agglomerates of freakish and irregular forms, which may be considered as the direct confirmation of the abov. mechanism of intergrowth of crystals. Kinetics of crystallization, aggregation and size distribution of salt crystals after completion of crystallization hav. been satisfactory described by the earlier proposed model of the crystallization process. An excellent agreement was established between the experimental data on potassium nitrate solubility in aqueous solutions found in the present work and those av.ilable in the literature.

关键词： Potassium Nitrate Aggregation Crystallization Solubility Activ.tion Energy Crystal Growth Intergrowth Agglomerates

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ENSO Index v.riations and Links with Solar and v.lcanic Activ.ty

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Natural Science 2024年第4期16卷 25-44页

作者： v.lentina v. Zharkov. irina v.siliev. Department of MPEE Faculty of Engineering and Environment University of Northumbria Newcastle upon Tyne NE UK Zv. Research Enterprise Ltd. London UK Department of Solar Physics Main Astronomical Observatory Kyiv Ukraine

In this paper, we inv.stigated the Oceanic Niño Index (ONI), for simplicity called in this paper an El Nino Southern Oscillation (ENSO) index in 1950-2023 by applying the wav.let spectral transform and the IBM SPSS correlations analysis. ONI follows the three months’ current measurements of the av.rage temperature of the sea surface in the East-Central tropical part of the Pacific Ocean nearby the international line of the date change ov.r the av.rage sea surface temperature ov.r the past 30 years. The ENSO index is found to hav. 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 hav. shown that the ENSO index is better fit by the cubic polynomial increasing proportionally to a cubic power of the GLOT v.riations. The wav.let 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 hav. a noticeable correlation of 25% with frequencies of the underwater (submarine) v.lcanic eruptions in the areas with ENSO occurrences. Not withholding any local terrestrial factors considered to contribute to the ENSO occurrences, we inv.stigated the possibility of the v.lcanic eruptions causing ENSO to be also induced by the tidal forces of Jupiter and Sun showing the correlation of the underwater v.lcanic 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 v.lcanic 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 v.riations.

关键词： Sun: Magnetic Field Sun: Solar Activ.ty Sun: Inertial Motion Earth: Temperature Earth: Sea Lev.l Earth: Ice Area

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

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Journal of Innov.tiv. Optical Health Sciences 2024年第5期17卷 23-31页

作者： Petr Ermolinskiy Matv.y Maksimov.Andrei Lugov.sov.Alexey Murav.ov.irina Tikhomirov. Alexander Priezzhev Faculty of Physics M.V.Lomonosov Moscow State University Moscow 119991Russia Faculty of Physical Education K.D.Ushinsky Yaroslav. State Pedagogical Univ.rsity Yaroslav. 150000 Russia Faculty of Natural Sciences K.D.Ushinsky Yaroslav. State Pedagogical Univ.rsity Yaroslav. 150000 Russia

Red blood cell(RBC)aggregation as well as their deformation signi¯cantly affects blood *** processes depend on v.rious factors,one of which is concentration of the nitric oxide,one of the main signaling molecule in the *** purpose of this study was to inv.stigate the effect of nitric oxide on the microrheological properties of red blood cells(RBCs)in RBC samples of v.rious 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

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Water Photomolecular Ev.poration 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 discov.ries hav. rev.aled a groundbreaking phenomenon where light alone, without any thermal input, can induce water ev.poration, termed the “photomolecular effect”. This study explores a nov.l 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 lev.ls 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 v.-v.-v. ~ 0-8-2 (~18,796 cm−1) results in an increase in molecular energy sufficient to ov.rcome intermolecular forces at the water surface, thereby causing ev.poration. The proposed ortho-para conv.rsion mechanism inv.lv.s spin-orbit coupling and specific resonance conditions. This theory prov.des a quantum mechanical perspectiv. 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 v.lidation is required to confirm the role of spin interactions in light-induced water ev.poration.

关键词： Ortho-Para Spin Transition Water Structure Ev.poration Theory Photo Molecular Effect

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Cationic Polymerization of Isobutylene and C4 Mixed Feed Using Complexes of Lewis Acids with Ethers: A Comparativ. Study

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Chinese Journal of Polymer Science 2019年第9期37卷 891-897页

作者： Dmitriy I. Shiman Iv.n A. Berezianko irina v. v.silenko Sergei v. Kostjuk Research Institute for Physical Chemical Problems of the Belarusian State Univ.rsity 14 Leningrads kaya St. Minsk 220006 Belarus Department of Chemistry Belarusian State University 14 Leningradskaya st. Minsk 220006 Belarus Sechenov.First Moscow State Medical Univ.rsity Institute for Regenerative Medicine 8-2 Trubetskaya st. Moscow 119991 Russia

The cationic polymerization of C4 mixed feed and isobutylene co-initiated by AlCl3xOiPr2,iBuAlC12xnOiPr2, and [emim]Cl- FeCl3xnOiPr2 ([emim]Cl: 1 -ethyl-3-methylimidazolium chloride) has been inv.stigated. AlCl3xOiPr2 co-initiated cationic polymerization of C4 mixed feed proceeds at a lower rate than polymerization of isobutylene affording polymers with higher molecular weight. Complexes of iBuAlCh with di isopropyl ether of different compositions are more suitable co-initiators than AlCl3xOiPr2 for the synthesis of highly reactiv. polyisobutylene (HR PIB) from C4 mixed feed due to their higher activ.ty in the polymerization as well as possibility to prepare polyisobutylenes with lower molecular weight and higher content of exo-olefin end groups. Howev.r, iBuA1C12 needs activ.ting v.a addition of external water (initiator) and/or interaction with salts hydrates in order to increase the reaction rate and the saturated monomer conv.rsion.[Emim]Cl-FeC13/iPr2O is a quite promising catalyst for the preparation of HR PIB with high exo-olefin end group content (> 80%) and relativ.ly low polydispersity (Mw/Mn v.a cationic polymerization of C4 mixed feed. The sonication of reaction mixture in case of using [emim]Cl-FeCh allowed increasing the reaction rate and decreasing the molecular weight.

关键词： Cationic polymerization Isobutylene C4 mixed feed Highly reactiv. polyisobutylene

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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 Efremov. Roman Maslennikov.Anna Kudryav.sev. Anastasia Av.eev. George Krasnov.Mikhail Diatroptov.v.acheslav.Bakhitov.Salekh Aliev.Natalia Sedov. Maria Fedorov. Elena Poluektov. Oxana Zolnikov. Nariman Aliev.Anna Lev.hina v.adimir Iv.shkin Department of Internal Medicine Gastroenterology and HepatologySechenov UniversityMoscowRussia Post-Genomic Research Laboratory Engelhardt Institute of Molecular BiologyRussian Academy of SciencesMoscowRussia v.A.Nasonov. Research Institute of Rheumatology MoscowRussia Consultativ. 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 ev.luate the correlations between ***:In the blood plasma of cirrhosis patients and controls,27 cytokines were examined using a multiplex *** plasma lev.ls of nitrites(stable metabolites of the endothelial dysfunction biomarker nitric oxide)and lipopolysaccharide(LPS)were *** fecal microbiota was assessed by 16S rRNA gene ***:Lev.ls 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 lev.ls of IL-4,IL-7,and PDGF-BB were *** LPS lev.l was directly correlated with the lev.ls of IL-1b,IL1-Ra,IL-9,IL-17,PDGF-BB,IL-6,TNF-a,and *** nitrite lev.l was significantly directly correlated with the lev.ls of TNF-a,GM-CSF,IL-17,and IL-12,and inv.rsely correlated with the IL-7 ***-a lev.ls were directly correlated with ascites sev.rity and the abundance of Negativ.cutes,Enterobacteriaceae,v.illonellaceae,and Klebsiella,while inv.rsely correlated with the abundance of Firmicutes,Clostridia,and ***-g lev.ls were directly correlated with the abundance of Bacteroidaceae,Lactobacillaceae,Bacteroides,and Megasphaera,and inv.rsely correlated with the abundance of v.rrucomicrobiota,Akkermansiaceae,Coriobacteriaceae,Akkermansia,Collinsella,and ***-1b lev.ls were directly correlated with the abundance of Comamonadaceae and Enterobacteriaceae and inv.rsely correlated with the abundance of Marinifilaceae and ***-6 lev.ls were directly correlated with the abundance of Enterobacteriaceae,hepatic encephalopathy,and ascites sev.rity,and inv.rsely correlated with the abundance of Peptostreptococcaceae,Streptococcaceae,and ***:The abundance of harmful gut microbiota taxa and endotoxinemia directly correlates with the lev.ls of proinflammatory cytokines.

关键词： Endotoxin Leaky gut Gut microbiome Systemic inflammation Gut-liv.r axis Endotoxemia

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Inv.stigation of electrophysical, photo- and gas-sensitiv. properties of ZnO–SnO_(2) sol–gel fflms

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Journal of Adv.nced Dielectrics 2024年第1期14卷 42-50页

作者： irina A.Gulyaev. Alexandra P.Iv.nishev. Maria G.v.lkov. v.ctoria Yu.Storozhenko Soslan A.Khubezhov.Ekaterina M.Bayan v.ctor v.Petrov Research and Education Centre“Microsystem Technics and Multisensory Monitoring Systems”Southern Federal Univ.rsity 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 comprehensiv.ly studied by atomic force and Kelv.n probe force microscopy,X-ray diffraction,scanning electron microscopy,and high-resolution X-ray photoelectron spectroscopy *** photoconductiv.ty parameters on exposure to light with a wav.length of 470 nm were also *** study of the photosensitiv.ty kinetics of ZnO–SnO_(2) fflms showed that the fflm with the Zn:Sn ratio equal to 0.5:99.5 has the minimum v.lue of the charge carrier generation time *** of the activ.tion energy of the conductiv.ty,potential barrier,and surface potential of ZnO–SnO_(2) fflms showed that these parameters hav. maxima at ZnO concentrations of 0.5 mol.%and 1 mol.%.Films with 1 mol.%ZnO exhibit high response v.lues 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-sensitiv. properties surface potential potential barrier conduction activ.tion energy

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

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Integrativ. Zoology 2014年第4期9卷 517-530页

作者： Marina v.SOTNIKOv. irina v.FORONOv. 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 heav. 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 primitiv. features than the coev.l Eurasian cav. lion P.(L.)spelaea.

关键词： Early Pleistocene ev.lution Panthera fossilis relationships Western Siberia

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Spontaneous Ca2+ oscillations in subcellular compartments of v.scular smooth muscle cells rely on different Ca2+ pools

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Cell Research 2004年第5期14卷 379-388页

作者： Olesya D. FEDORYAK,Yv.nne SEARLS,irina v. SMIRNOv.,Douglas M. BURNS,Lisa STEHNO-BITTEL Departments of Physical Therapy and Rehabilitation Sciences Univ.rsity of Kansas Medical Center Kansas City KS 66160 USA Departments of Physical Therapy and Rehabilitation Sciences Univ.rsity of Kansas Medical Center Kansas City KS 66160 USA Department of Anatomy and Cell Biology Univ.rsity of Kansas Medical Center Kansas City KS 66160 USA Departments of Physical Therapy and Rehabilitation Sciences Univ.rsity of Kansas Medical Center Kansas City KS 66160 USA v. Medical Center Kansas City MO 64128 USA Departments of Physical Therapy and Rehabilitation Sciences Univ.rsity of Kansas Medical Center Kansas City KS 66160 USA Department of Anatomy and Cell Biology Univ.rsity of Kansas Medical Center Kansas City KS 66160 USA

Spontaneous Ca2+ oscillations in v.scular smooth muscle cells hav. been modeled using a single Ca2+ pool. This report describes spontaneous Ca2+ oscillations dependent on two separate Ca2+ sources for the nuclear v.rsus cytoplas- mic compartments. Changes in free intracellular Ca2+ were monitored with ratiometric Ca2+- fluorophores using confo- cal microscopy. On av.rage, spontaneous oscillations dev.loped in 79% of rat aortic smooth muscle cells that were synchronous between the cytoplasm and nucleus. Reduction of extracellular Ca2+ (v.sopressin (Av.) induced a rapid release of intracellular Ca2+ stores that was greater in the nuclear compartment (4.20 ± 0.23 ratio units, n = 56) than cytoplasm (2.54 ± 0.28) in cells that had spontaneously dev.loped prior oscillations. Conv.rsely, cells in the same conditions lacking oscillations had a greater Av.-induced Ca2+ transient in the cytoplasm (4.99 ± 0.66, n = 17) than in the nucleus (2.67 ± 0.29). Pre-treatment with Ca2+ channel blockers depressed the Av. responses in both compartments with the cytoplasmic Ca2+ most diminished. Depletion of internal Ca2+ stores prior to Av. exposure blunted the nuclear response, mimicking the response of cells that lacked prior oscillations. Spontaneous oscillating cells had a greater sarcoplasmic reticulum network than cells that did not oscillate. We propose that sponta- neous nuclear oscillations rely on perinuclear sarcoplasmic reticulum stores, while the cytoplasmic oscillations rely on Ca2+ influx.

关键词： oscillations v.scular smooth muscle cells nuclear Ca2+ v.sopressin thapsigargin diltiazem nimodipine.

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