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Unveiling the nature of Polar-ring Galaxies from Deep Imaging

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Research in Astronomy and Astrophysics 2022年第11期22卷 34-50页

作者： aleksandr V.Mosenkov Vladimir P.Reshetnikov Maria n.Skryabina Zacory Shakespear Department of Physics and Astronomy N283 ESCBrigham Young UniversityProvoUT 84602USA Central(Pulkovo)Astronomical Observatory Russian Academy of SciencesPulkovskoye Chaussee 65/1196140 St.PetersburgRussia St.Petersburg State University 7/9 Universitetskaya Nab.199034 St.PetersburgRussia

General structural properties and low surface brightness tidal features hold important clues to the formation of *** this paper,we study a sample of polar-ring galaxies(PRGs)based on optical imaging from the Sloan Digital Sky Survey Stripe 82 and other deep *** investigate the deepest images of candidates for PRGs to *** carry out photometric decomposition on the host galaxies and associated polar structures that allows us to derive the structural properties of both *** are able to detect very faint tidal structures around most PRGs in our *** several galaxies,we can directly observe the formation of the polar ring due to merging,which is manifested in debris of the victim galaxy and an arc-like polar structure made up of its *** a few cases,we can discern signs of tidal *** results obtained indicate that the gravitational interaction and merging of galaxies are the most plausible mechanisms for the formation of PRGs.

关键词： data analysis techniques:photometric galaxies:structure

Device-based neuromodulation for cardiovascular diseases and patient’s age

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Journal of Geriatric Cardiology 2022年第11期19卷 876-893页

作者： Evgeny n Mikhaylov nigar Z Gasimova natalia n Belyaeva Heber Ivan Condori Leandro aleksandr D Vakhrushev Evgeny V Shlyakhto Almazov national Medical Research Centre Saint-PetersburgRussia

The autonomic nervous system plays an important role in the pathogenesis of cardiovascular *** aging,autonomic activity changes,and this impacts the physiological reactions to internal and external *** sympathetic and parasympathetic responses seem to decline,reflecting functional and structural changes in nervous *** some investigators suggested that both the sympathetic and parasympathetic activities were suppressed,others found that only the parasympathetic activity was suppressed while the sympathetic activity *** addition,cardiac innervation progressively diminishes with ***,one may suggest that neuromodulation interventions may have different effects,and older age groups can express an attenuated *** article aims to discuss the effect of device-based neuromodulation in different cardiovascular diseases,depending on the patient’s ***,we cover renal denervation,pulmonary artery denervation,baroreceptor activation therapy,vagus nerve stimulation,spinal cord stimulation,ganglionated plexi ablation for the management of arterial and pulmonary hypertension,heart failure,angina and *** results of many clinical studies appeared to be *** view of the low rate of positive findings in clinical studies incorporating neuromodulation approaches,we suggest the underestimation of advanced age as a potential contributing factor to poorer *** of outcomes between different age groups in clinical trials may shed more light on the true effects of neuromodulation when neutral/ambiguous results are obtained.

关键词： stimulation cardiovascular diseases

nucleation of dislocations and twins in fcc nanocrystals: Dynamics of structural transformations

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Journal of Materials Science & Technology 2019年第1期35卷 201-206页

作者： aleksandr V.Korchuganov aleksandr n.Tyumentsev Konstantin P.Zolnikov Igor Yu.Litovchenko Dmitrij S.Kryzhevich Elazar Gutmanas Shouxin Li Zhongguang Wang Sergey G.Psakhie Institute of Strength Physics and Materials Science of Siberian Branch of Russian Academy of Sciences national Research Tomsk State University Technion–Israel Institute of Technology Shenyang national Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences

This paper reports on a molecular dynamics study of structural rearrangements in a copper nanocrystal during nucleation of plastic deformation under uniaxial tension. The study shows that the resulting nucleation of partial dislocations on the free surface and their glide occurs through local fcc→bcc→hcp transformations via consistent atomic displacements. We propose an atomic model for the generation of dislocations and twins based on local reversible fcc→bcc→fcc transformations, with the reverse one proceeding through an alternative system. The model gives an insight into possible causes and mechanisms of the generation of partial dislocations and mechanical twins in two and more adjacent planes of plastically deformed nanocrystals. The obtained data allow a better understanding of how plasticity is generated in nanostructured materials.

关键词： Lattice defects Dislocation nanotwin Atomic model Molecular dynamics simulations

Agglomeration of coal and polyethylene mixtures during fixed‑bed co‑gasification

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International Journal of Coal Science & Technology 2024年第2期11卷 91-100页

作者： Igor G.Donskoy aleksandr n.Kozlov Maksim V.Penzik Denis A.Svishchev Lu Ding Melentiev Energy Systems Institute Russian Federation130 Lermontova StreetIrkutskRussia 664033 East China University of Science and Technology 130 Meilong RoadShanghai 200237China

The article presents the results of experimental studies on the gasification of mixtures of brown coal and polyethylene(up to 20 wt%fraction)in a laboratory *** work aims to study the agglomeration process during the heating and oxidation of the *** measurement results(gas composition,pressure drop)provide indirect information on the dynamics of thermal decomposition and structural changes in the fuel *** have shown that the interaction between polyethylene and a coal surface leads to the formation of dense agglomerates,in which the molten polymer acts as a *** form as a result of interfacial interactions between components and filtration flow *** hydrogen/carbon ratio in the solid residue of coal-polyethylene co-gasification increases from 0.07–0.2 to 1.11,indicating the formation of stable hydrocarbon compounds on the carbon *** conducted research makes it possible to identify possible interactions between chemical reactions and transfer processes that lead to agglomeration in mixtures of coal with polyethylene.

关键词： Coal Polyethylene Gasification Combustion Agglomeration

Kinetics and mechanism of the low-energy β-a phase transition of the second kind in 2,4-dinitroanisole

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Defence Technology（防务技术） 2024年第10期40卷 210-224页

作者： aleksandr V.Stankevich nikolay A.Rasputin Anisa KhRudina Gennady L.Rusinov Vera I.Filyakova Valery n.Charushin I.Ya. Postovsky Institute of Organic Synthesis Ural Branch of the Russian Academy of Sciencesekaterinburg 620108russia Russian Federal nuclear Center-Zababakhin All-Russia Research Institute of Technical Physics snezhinsk 456770russia Kazan national Research Technological University kazan 420015russia

In this work, comprehensive studies of 2,4-dinitroanisole(2,4DnAn) were carried out using powder thermorentgenography of the internal standard. The time of the complete polymorphic transition in the solid phase β→a in 2,4DnAn under various combinations of conditions has been determined. It has been established that, regardless of the season of manufacture of the substance, when it is stored for 8-9months, with a change in ambient temperature from minus 30℃ to plus 30℃, a complete polymorphic transition β→a occurs. When stored in conditions below minus 5℃, polymorphic transition does not occur. When stored in conditions above plus 30℃ in a closed container, polymorphic transition occurs within 3 weeks. The polymorphic transition is accompanied by a decrease in density by 1.3%-1.5% and an increase in melting temperature by 10-12℃, depending on the degree of purity of the starting substance. The activation energy of the molecular rearrangement was 68-70 k J/mol(16.5 ± 3 kcal/mol). The mechanism of polymorphic transition has been evaluated, which is presumably based on internal homodiffusion and energy transfer to the surface of the mass of powder particles and the product. The average activation energy of the polymorphic transition process was 110 ± 6.2 k J/mol(26.2 kcal/mol). In an open container, reactions proceed by a homogeneous mechanism, and in a closed container by a heterogeneous mechanism involving the gas phase.

关键词： Energetic materials Melt-castable 2,4-Dinitroanisole Polymorphic transition Kinetics Mechanism Homodiffusion Sublimation

In-situ Post-Synthetic Treatment of CsPbBr3 Perovskite nanocrystals in nanoporous Silica Microspheres

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Chinese Journal of Chemistry 2024年第22期42卷 2779-2787页

作者： Danila A.Tatarinov Jinfeng Xie Qingyi Qian Qingqing Wang nadezhda A.Maslova Lyubov n.Borodina aleksandr P.Litvin He Huang School of Optoelectronic Science and Engineering Soochow UniversitySuzhouJiangsu 215006China Phys nano Department ITMO UniversitySt.Petersburg197101 Russia Research Park Saint Petersburg State UniversitySt.Petersburg199034 Russia Schoolof Materials Science and Engineering Jjilin UniversityChangchunJilin 130012China

Comprehensive Summary Inorganic lead halide perovskite(LHP)nanostructures,represented by formula CsPbX3(X=Cl,Br,I),have garnered considerable interest for their exceptional optical properties and diverse *** their potential,challenges such as environmental degradation ***-situ synthesis within protective materials pores is a promising way to address this ***,confining perovskite nanostructures into porous matrices during the synthesis can limit their photoluminescence quantum yield(PL QY)and tunability of optical *** post-treatment approaches exist to improve the properties of LHP and achieve their desired functionalities,but these strategies have not been explored for LHP confined in mesoporous ***,we demonstrate the efficacy of in-situ post-synthetic treatments to improve the optical properties of CsPbBr3 nanocrystals grown in nanoporous silica *** passivation with Br–ion-containing precursors boosts PL QY,while anion-assisted cation doping with Mn2+ions introduces a new PL *** adjustment of precursor amount and doping duration enables precise control over the optical properties of LHP,while additional coating with a SiO2 shell enhances their stability in polar solvents,expanding the potential applications of these composites.

关键词： Perovskite nanocrystals In-situ synthesis Mesoporous materials Defect passivation Anion-assisted cation doping Silicamicrospheres

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超宽带多注速调管的模拟研究

电子与信息学报 2006年第1期28卷 180-184页

作者：沈斌丁耀根 aleksandr n.Sandalov Vladimir E.Rodjakin aleksandra n.Chashurina 中国科学院电子学研究所 Radiophysics Chair

本文介绍了多注速调管的发展历史和现状,以及速调管模拟软件的发展情况。用1．5维软件Klystron -MSU和2．5维软件Arsenal-MSU对超宽带多注速调管进行了设计计算,并对计算结果进行分析,得到了比较好的输出特性。计算结果表明可以实现该... 详细信息

本文介绍了多注速调管的发展历史和现状,以及速调管模拟软件的发展情况。用1．5维软件Klystron -MSU和2．5维软件Arsenal-MSU对超宽带多注速调管进行了设计计算,并对计算结果进行分析,得到了比较好的输出特性。计算结果表明可以实现该超宽带多注速调管,其带宽10-14％,增益40-50dB,效率40-50％。

关键词：多注速调管 Klystron-MSU Arsenal-MSU 电子注通过率输出特性

Artemia cyst production in Russia

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Chinese Journal of Oceanology and Limnology 2015年第6期33卷 1436-1450页

作者： Liudmila I.LITVInEnKO aleksandr I.LITVInEnKO Elena G.BOIKO Kirill KUTSAnOV Federal State Unitary Enterprise nd Production Centre of Fishery> GosrybcenterTyumenRussia State Agrarian University of northern Urals

In Western Siberia(Russia) there are about 100 Artemia lakes with total area over 1 600 km *** these lakes are located between 51°–56°n and 61°–82°*** general these lakes are shallow(depth less than 1.5 m),small or medium size(0.1 to 10 km 2);they are chloride;their total salinity is from 40 to 250 g/*** harvesting of cysts per year is only in 20–40 *** Russia 550 tons of dry Artemia cysts(14%–18% of the world production) were harvested *** includes about 350 tons in the Altai region and 200 tons in other *** our regular 20-year study period the cyst harvest was:95 tons in Kurgan;65 tons in Omsk,20 tons in novosibirsk,20 tons in *** of increasing cyst harvest in Russia are considered in this *** the last 30 years the harvest of cysts in Russia has increased from 7–20 to 500–600 tons.A significant influence of dryness of the year was found on productivity in selected lakes,but taken for all the lakes together,the relationship was not *** optimal salinity for productivity of cysts in the lakes was *** of productivity of the lakes and the harvesting results showed that the stocks of cysts are underutilized by approximately 1.7 times.

关键词： Artemia brine shrimp cyst production Russian saline lakes population dynamics aquacultureindustry

Kinetics of 2-Methylbutene-2 Epoxidation with 2-Methylbutane Hydroperoxide

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Journal of Chemistry and Chemical Engineering 2013年第4期7卷 356-363页

作者： Valentin n. Sapunov aleksandr A. Petukhov Liubov A. Petukhova University of Chemical Technology Moscow Russia national Research Technological University (KnRTU) Kazan Russia

The kinetics of epoxidation of methylbutene with structurally identical methylbutane hydroperoxide was studied in the presence of a molybdenum catalyst. The analysis of the rate curves suggested the most probable scheme of the process. The revealed features of the process and its mathematical description make it possible to more competently design a reactor unit for the commercial production of isoprene according to the developed scheme. The main kinetic constants were calculated.

关键词： Kinetic 2-methylbutene-2 epoxidation 2-methylbutane hydroperoxide molybdenum catalyst mathematical description.