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Method for passivation of propellant residues in orbital stage tank of launch vehicle

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Chinese Journal of Aeronautics 2024年第1期37卷 64-76页

作者： Valeriy TRUSHLYAKOV Ivan LESNYAK alexey PANICHKIN Department of Aviation and Rocket Building Omsk State Technical UniversityOmsk 644050Russia Sobolev Institute of Mathematics of the Siberian Branch of Russian Academy of Sciences Novosibirsk 630090Russia

The problem of removing unused liquid propellant residues from the tanks of spent spacecraft and orbital stages of Launch Vehicles(LV)leads to their explosion and the formation of space debris in orbits.To provide a solution to this problem,a method for removing liquid propellant residues from the LV tanks after the mission completion is proposed.The method is based on the gasification of liquid propellant residues in the tanks under acoustic-vacuum exposure and the discharge of the gasification products into the surrounding outer space.Experimental investigations were carried out on a Ground-based Experimental Installation(GEI)to determine the coefficient of heat transfer from the surface of an acoustic radiator to a liquid.The obtained coefficient was then used to calculate the energy costs for the gasification of kerosene.Numerical estimates are given on the example of the tank with kerosene residues from a spent second stage of the LV“Soyuz-2.1 v”.The optimal discharge rate at which kerosene does not freeze is 0.14 m^(3)/s.Moreover,the acoustic exposure leads to an increase in the mass of evaporated kerosene over a given time by96.1%,and the energy costs are 1756.7 kJ(approximately 50% of the remaining electrical energy).

关键词： Propellant Weightlessness Liquid evaporation Heat and mass transfer Acoustics Vacuum Vapor bubbles

Convection and Stratification of Temperature and Concentration

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Fluid Dynamics & Materials Processing 2024年第6期20卷 1351-1364页

作者： alexey Fedyushkin Laboratory of Complex Fluid Mechanics Ishlinsky Institute for Problems in Mechanics RASMoscow119526Russia

This study is devoted to an analysis of natural convection and the emergence of delamination in an incompressible fluid encapsulated in a closed region heated from the side.Weak,medium and intensive modes of stationary laminar thermal and thermo-concentration convection are considered.It is shown that nonlinear flow features can radically change the flow structure and characteristics of heat and mass transfer.Moreover,the temperature and concentration segregation in the center of the square region display a non-monotonic dependence on the Grashof number(flow intensity).The formation of a nonstationary periodic structure of thermal convection in boundary layers and in the core of a convective flow in the closed region is also examined.Details of the formation of countercurrents inside the region with the direction opposite to the main convective flow are given.Finally,the influence of vertical and horizontal vibrations on oscillatory convection is analyzed in detail.

关键词： Natural convection stratification segregation numerical simulation vibrations

Influence of the Atlantic Multidecadal Oscillation and Interdecadal Pacific Oscillation on Antarctic surface air temperature during 1900 to 2015

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Acta Oceanologica Sinica 2024年第3期43卷 48-58页

作者： Cuijuan Sui Lejiang Yu alexey YuKarpechko Licheng Feng Shan Liu Key Laboratory of Marine Hazards Forecasting National Marine Environmental Forecasting CenterMinistry of Natural ResourcesBeijing 100081China Key Laboratory for Polar Science Polar Research Institute of ChinaMinistry of Natural ResourcesShanghai 200136China Finnish Meteorological Institute HelsinkiFI-00101Finland

The importance of the Atlantic Multidecadal Oscillation(AMO)and Interdecadal Pacific Oscillation(IPO)in influencing zonally asymmetric changes in Antarctic surface air temperature(SAT)has been established.However,previous studies have primarily concentrated on examining the combined impact of the contrasting phases of the AMO and IPO,which have been dominant since the advent of satellite observations in 1979.This study utilizes long-term reanalysis data to investigate the impact of four combinations of+AMO+IPO,–AMO–IPO,+AMO–IPO,and–AMO+IPO on Antarctic SAT over the past 115 years.The+AMO phase is characterized by a spatial mean temperature amplitude of up to 0.5℃over the North Atlantic Ocean,accompanied by positive sea surface temperature(SST)anomalies in the tropical eastern Pacific and negative SST anomalies in the extratropical-mid-latitude western Pacific,which are indicative of the+IPO phase.The Antarctic SAT exhibits contrasting spatial patterns during the+AMO+IPO and+AMO–IPO periods.However,during the–AMO+IPO period,apart from the Antarctic Peninsula and the vicinity of the Weddell Sea,the entire Antarctic region experiences a warming trend.The most pronounced signal in the SAT anomalies is observed during the austral autumn,whereas the combination of–AMO and–IPO exhibits the smallest magnitude across all the combinations.The wavetrain excited by the SST anomalies associated with the AMO and IPO induces upper-level and surface atmospheric circulation anomalies,which alter the SAT anomalies.Furthermore,downward longwave radiation anomalies related to anomalous cloud cover play a crucial role.In the future,if the phases of AMO and IPO were to reverse(AMO transitioning to a negative phase and IPO transitioning to a positive phase),Antarctica could potentially face more pronounced warming and accelerated melting compared to the current observations.

关键词： Atlantic Multidecadal Oscillation(AMO) Interdecadal Pacific Oscillation(IPO) surface air temperature Antarctic wavetrain Rossby wave source

Decline and fall of aging astrocytes:the human perspective

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Neural Regeneration Research 2025年第6期 1713-1714页

作者： Alexei Verkhratsky alexey Semyanov Faculty of Biology Medicine and Health The University of Manchester Department of Neurosciences University of the Basque Country UPV/EHU and CIBERNED Department of Forensic Analytical Toxicology School of Forensic Medicine China Medical University Department of Stem Cell Biology State Research Institute Centre for Innovative Medicine International Collaborative Center on Big Science Plan for Purinergic Signalling Chengdu University of Traditional Chinese Medicine Department of Physiology Jiaxing University College of Medicine

“Last scene of all that ends this strange, eventful history, is second childishness and mere oblivion. I am sans teeth, sans eyes, sans taste, sans everything.”William Shakespeare‘As You Like It' Act 2, Sc. 7, l. 139Aging of the human brain is characterized by a progressive decline of its functional capacity; this decline however varies widely, and cognitive longevity differs substantially between individuals.

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Irisin/BDNF signaling in the muscle-brain axis and circadian system: A review

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The Journal of Biomedical Research 2024年第1期38卷 1-16页

作者： alexey N.Inyushkin Vitalii S.Poletaev Elena M.Inyushkina Igor S.Kalberdin Andrey A.Inyushkin Department of Human&Animal Physiology Samara National Research UniversitySamara 443011Russia.

In mammals,the timing of physiological,biochemical and behavioral processes over a 24-h period is controlled by circadian rhythms.To entrain the master clock located in the suprachiasmatic nucleus of the hypothalamus to a precise 24-h rhythm,environmental zeitgebers are used by the circadian system.This is done primarily by signals from the retina via the retinohypothalamic tract,but other cues like exercise,feeding,temperature,anxiety,and social events have also been shown to act as non-photic zeitgebers.The recently identified myokine irisin is proposed to serve as an entraining non-photic signal of exercise.Irisin is a product of cleavage and modification from its precursor membrane fibronectin typeⅢdomain-containing protein 5(FNDC5)in response to exercise.Apart from well-known peripheral effects,such as inducing the"browning"of white adipocytes,irisin can penetrate the blood-brain barrier and display the effects on the brain.Experimental data suggest that FNDC5/irisin mediates the positive effects of physical activity on brain functions.In several brain areas,irisin induces the production of brain-derived neurotrophic factor(BDNF).In the master clock,a significant role in gating photic stimuli in the retinohypothalamic synapse for BDNF is suggested.However,the brain receptor for irisin remains unknown.In the current review,the interactions of physical activity and the irisin/BDNF axis with the circadian system are reconceptualized.

关键词： irisin brain-derived neurotrophic factor peroxisome proliferator-activated receptorγcoactivator 1α circadian rhythm circadian system muscle-brain axis

Active Cancelation of Acoustic Noise in Waveguides by Standard Control Task Decision Usage

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Journal of Applied Mathematics and Physics 2024年第4期12卷 1188-1202页

作者： alexey A. Pudovkin Russian Academy of Sciences Prokhorov General Physics Institute Moscow Russia

Cybernetic decision variants were analyzed in order to use for physical task of active noise cancelation. 10 dB mean active noise cancellation is demonstrated in two decades frequency band by usage of cybernetic decision for acoustical duct physical scale model. The used decision was found on minimization of acoustical field power transfer function from the beginning of waveguide to their end.

关键词： Waveguide Noise Active Cancelation Control Synthesis Procedure H2

Insights into the hydrogen evolution reaction in vanadium redox flow batteries:A synchrotron radiation based X-ray imaging study

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Journal of Energy Chemistry 2024年第4期91卷 132-144页

作者： Kerstin Köble alexey Ershov Kangjun Duan Monja Schilling Alexander Rampf Angelica Cecilia TomášFaragó Marcus Zuber Tilo Baumbach Roswitha Zeis Helmholtz Institute Ulm Karlsruhe Institute of Technology89081 UlmGermany Laboratory for Applications of Synchrotron Radiation Karlsruhe Institute of Technology76131 KarlsruheGermany Institute for Photon Science and Synchrotron Radiation Karlsruhe Institute of Technology76344 Eggenstein-LeopoldshafenGermany Department of Electrical Electronicsand Communication EngineeringFaculty of EngineeringFriedrich-Alexander-Universität Erlangen-Nürnberg(FAU)91058 ErlangenGermany Department of Mechanical and Industrial Engineering University of TorontoToronto M5S 3G8OntarioCanada

The parasitic hydrogen evolution reaction(HER)in the negative half-cell of vanadium redox flow batteries(VRFBs)causes severe efficiency losses.Thus,a deeper understanding of this process and the accompanying bubble formation is crucial.This benchmarking study locally analyzes the bubble distribution in thick,porous electrodes for the first time using deep learning-based image segmentation of synchrotron X-ray micro-tomograms.Each large three-dimensional data set was processed precisely in less than one minute while minimizing human errors and pointing out areas of increased HER activity in VRFBs.The study systematically varies the electrode potential and material,concluding that more negative electrode potentials of-200 m V vs.reversible hydrogen electrode(RHE)and lower cause more substantial bubble formation,resulting in bubble fractions of around 15%–20%in carbon felt electrodes.Contrarily,the bubble fractions stay only around 2%in an electrode combining carbon felt and carbon paper.The detected areas with high HER activity,such as the border subregion with more than 30%bubble fraction in carbon felt electrodes,the cutting edges,and preferential spots in the electrode bulk,are potential-independent and suggest that larger electrodes with a higher bulk-to-border ratio might reduce HER-related performance losses.The described combination of electrochemical measurements,local X-ray microtomography,AI-based segmentation,and 3D morphometric analysis is a powerful and novel approach for local bubble analysis in three-dimensional porous electrodes,providing an essential toolkit for a broad community working on bubble-generating electrochemical systems.

关键词： Vanadium redox flow battery Synchrotron X-ray imaging Tomography Hydrogen evolution reaction Gas bubbles Deep learning

Dry Mix Slag—High-Calcium Fly Ash Binder. Part Two: Durability

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Materials Sciences and Applications 2024年第3期15卷 37-51页

作者： alexey Brykov Mikhail Voronkov Department of Chemical Technology of High-Melting Non-Metallic and Silicate Materials Saint Petersburg State Institute of Technology St. Petersburg Russia

This work investigates durability of cement-free mortars with a binder comprised of ground granulated blast furnace slag (GGBFS) activated by high-calcium fly ash (HCFA) and sodium carbonate (Na2CO3): the soundness, sulfate resistance, alkali-silica reactivity and efflorescence factors are considered. Results of tests show that such mortars are resistant to alkali-silica expansion. Mortars are also sulfate-resistant when the amount of HCFA in the complex binder is within a limit of 10 wt%. The fineness of fly ash determines its’ ability to activate GGBFS hydration, and influence soundness of the binder, early strength development, sulfate resistance and efflorescence behavior. The present article is a continuation of authors’ work, previously published in MSA, Vol. 14, 240-254.

关键词： Ground Granulated Blast-Furnace Slag High-Calcium Fly-Ash Sodium Car-bonate Blast-Furnace Slag Binder Durability ASR Sulfate Attack Soundness Efflorescence

Prognostic and predictive role of immune microenvironment in colorectal cancer

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 643-652页

作者： Olesya Kuznetsova Mikhail Fedyanin Larisa Zavalishina Larisa Moskvina Olga Kuznetsova Alexandra Lebedeva alexey Tryakin Galina Kireeva Gleb Borshchev Sergei Tjulandin Ekaterina Ignatova Department of Chemotherapy Federal State Budgetary Institution(N.N.Blokhin National Medical Research Center of Oncology)of the Ministry of Health of the Russian FederationMoscow 115478Russia Department of Pathology Russian Medical Academy of Continuous Professional EducationMoscow 123242Russia OncoAtlas LCC Moscow 115478Russia Federal State Budgetary Institution“National Medical and Surgical Center named after N.I.Pirogov”of the Ministry of Health of the Russian Federation Moscow 105203Russia STOONCO:Science and Technology in Oncology Moscow 115478Russia

Colorectal cancer(CRC)represents a molecularly heterogeneous disease and one of the most frequent causes of cancer-related death worldwide.The traditional classification of CRC is based on pathomorphological and molecular character-istics of tumor cells(mucinous,ring-cell carcinomas,etc.),analysis of mechanisms of carcinogenesis involved(chromosomal instability,microsatellite instability,CpG island methylator phenotype)and mutational statuses of commonly altered genes(KRAS,NRAS,BRAF,APC,etc.),as well as expression signatures(CMS 1-4).It is also suggested that the tumor microenvironment is a key player in tumor progression and metastasis in CRC.According to the latest data,the immune microenvironment can also be predictive of the response to immune checkpoint inhibitors.In this review,we highlight how the immune environment influences CRC prognosis and sensitivity to systemic therapy.

关键词： Immunoscore Immune microenvironment Colorectal cancer Gastrointestinal cancers Predictive biomarkers Digital pathology