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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

Liquid superlubricity of lubricants containing hydroxyl groups and their aqueous solution under rolling/sliding conditions

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Friction 2024年第1期12卷 164-173页

作者： Tomáš POLÁČEK Petr ŠPErKA ivan KŘUPKA Faculty of Mechanical Engineering Brno University of TechnologyBrno 61669Czech Republic

Macroscale rolling/sliding conditions are in the superlubricity,a little-studied topic so far.The purpose of this paper is to examine the formation of elastohydrodynamic lubrication(EHL)films by water-based lubricants(glycerol and polyethylene glycol(PEG)),providing superlubricous friction.Experiments were carried out on an optical ball-on-disc tribometer under rolling/sliding conditions.The film thickness was measured by the thin film colorimetric interferometry,and the viscosity of liquids was measured by rotational and high-pressure falling body viscometers.The results show that tribochemical reactions are not the mandatory reason for friction to reach the superlubricity level when using the water-based lubricants.The studied liquids themselves are almost Newtonian.With the addition of water,the signs of shear thinning behavior disappear even more.Suitable conditions for this type of lubricant can be predicted using the known Hamrock–Dowson equations.An anomaly in the thickness of the lubricants was observed as an abrupt change at certain conditions.The more PEG there is in the lubricant,the higher the thickness at the beginning of the jump.

关键词： macroscale superlubricity super low traction water-based lubricants elastohydrodynamic lubrication(EHL) film thickness

Witness for resolution: post-conflict quadratic affiliation in semi-free ranging pigs

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Current Zoology 2024年第2期70卷 233-243页

作者： ivan Norscia Edoardo Collarini Carlo robino Elena chierto Giada Cordoni Department of Life Sciences and Systems Biology University of TorinoVia Accademia Albertina 1310123 TorinoItaly Department of Public Health Sciences and Pediatric s University of TorinoC.So Galileo Galilei 2210126 TorinoItaly

In social mammals,post-conflict resolution can involve the reunion of former opponents(reconciliation),spontaneous/solicited post-conflict affliation of a third party with either opponent(triadic contacts),and affiliation between other individuals(hereafter bystanders;quadratic contacts).Quadratic contacts-possibly informing complex cognitive abilities-have been neglected in post-conflict studies.We investi-gated quadratic affliation in semi-free ranging pigs Sus scrofa,at the ethical farm Parva-Domus(Cavagnolo,Italy).Kinship was known.We collected behavioral data on adult pigs(n=104)via video recordings(43 h)followed by video analyses.Affiliative and anxiety behaviors between bystanders were collected under post-conflict(PC;following a conflict between non-bystanders)and matched-control(MC;no conflict)conditions.Quadratic affiliation was present in pigs,as bystanders affliated more in PC than MC,and such affiliation was followed by a decrease in the anxiety behaviors of both the interacting bystanders.Thus,quadratic contacts may be partly aimed at reducing one's own anxiety(intrinsic regulation).Quadratic affiliation was highest between closely related bystanders,which suggests that such affiliation may be most effective when close kin is involved.Quadratic affiliation was lowest after reconciliation and spontaneous triadic contacts.This suggests that direct peacemaking between opponents and spontaneous triadic contacts with close kin may most likely replace quadratic affiliation.Hence,pigs can be influenced by the negative events that affect other pigs-but not themselves-and their response may be modulated by social factors.Such non-random quadratic affiliation may point toward the presence of elements of social appraisal abilities inpigs.

关键词： anxiety reduction emotional regulation reconciliation social appraisal triadic contacts.

Expect the unexpected:Brown tumor of the mandible as the first manifestation of primary hyperparathyroidism

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World Journal of Clinical Cases 2024年第7期12卷 1200-1204页

作者： Ana Majic Tengg Maja Cigrovski Berkovic ivan Zajc ivan Salaric Danko Müller Iva Markota Department of Endocrinology DiabetesMetabolic Diseases and Clinical PharmacologyClinical Hospital DubravaZagreb 10000Croatia Department for Sport and Exercise Medicine Faculty of Kinesiology University of ZagrebZagreb 10000Croatia Department of Oral Surgery Clinical Hospital DubravaZagreb 10000Croatia University of Zagreb School of Dental Medicine Zagreb 10000Croatia Clinical Department of Pathology and Cytology Clinical Hospital DubravaZagreb 10000Croatia

Hyperparathyroidism(HPT)is a condition in which one or more parathyroid glands produce increased levels of parathyroid hormone(PTH),causing disturbances in calcium homeostasis.Most commonly HPT presents with asymptomatic hypercalcemia but the clinical spectrum may include disturbances reflecting the combined effects of increased PTH secretion and hypercalcemia.Brown tumors are rare,benign,tumor-like bone lesions,occurring in 1.5%to 4.5%of patients with HPT,as a complication of an uncontrolled disease pathway,and are nowadays rarely seen in clinical practice.The tumor can appear either as a solitary or multifocal lesion and usually presents as an asymptomatic swelling or a painful exophytic mass.Furthermore,it can cause a pathological fracture or skeletal pain and be radiologically described as a lytic bone lesion.The diagnosis of a brown tumor in HPT is typically confirmed by assessing the levels of serum calcium,phosphorus,and PTH.Although when present,brown tumor is quite pathognomonic for HPT,the histologic finding often suggests a giant cell tumor,while clinical presentation might suggest other more frequent pathologies such as metastatic tumors.Treatment of brown tumors frequently focuses on managing the underlying HPT,which can often lead to regression and resolution of the lesion,without the need for surgical intervention.However,in refractory cases or when dealing with large symptomatic lesions,surgical treatment may be necessary.

关键词： Brown tumor Hyperparathyroidism Lytic bone lesions Giant cell tumor

Influence of Methane-Hydrogen Mixture characteristics on Compressor Vibrations

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Fluid Dynamics & Materials Processing 2024年第5期20卷 1031-1043页

作者： Vladimir Ya.Modorskii ivan E.cherepanov High Performance Computing Center Perm National Research Polytechnic UniversityPerm614990Russia

A transition to clean hydrogen energy will not be possible until the issues related to its production, transportation,storage, etc., are adequately resolved. Currently, however, it is possible to use methane-hydrogen mixtures.Natural gas can be transported using a pipeline system with the required pressure being maintained by gascompression stations. This method, however, is affected by some problems too. Compressors emergency stopscan be induced by vibrations because in some cases, mechanical methods are not able to reduce the vibrationamplitude. As an example, it is known that a gas-dynamic flow effect in labyrinth seals can lead to increasedvibrations. This paper presents the numerical simulation of rotor oscillations taking into account a gas-dynamicload. The influence of a transported mixture on the oscillatory process is investigated. Mixtures consisting ofmethane and hydrogen in various proportions and an air mixture are considered. The results are discussed forvarious operating pressures and include the rotor motion trajectories and oscillation frequency spectra obtainednumerically. It is shown that the gas mixture composition has a significant effect on the oscillations and theiroccurrence. Hydrogen as a working fluid reduces the vibration amplitude. Operating a compressor with hydrogenleads to a decrease in the resonant frequency, bringing it closer to the operating one. However, the operatingpressure at which maximum oscillations are observed depends slightly on the gas mixture composition.

关键词： Seal stabilities vibration FSI CFD multiphase flows hydrogen

Interatomic Interaction Models for Magnetic Materials:recent Advances

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chinese Physics Letters 2024年第6期41卷 54-66页

作者： Tatiana S.Kostiuchenko Alexander V.Shapeev ivan S.Novikov Emanuel Institute of Biochemical Physics rAS 4 Kosygin StreetMoscow119334Russian Federation Independent investigator

Atomistic modeling is a widely employed theoretical method of computational materials science.It has found particular utility in the study of magnetic materials.Initially,magnetic empirical interatomic potentials or spinpolarized density functional theory(DFT)served as the primary models for describing interatomic interactions in atomistic simulations of magnetic systems.Furthermore,in recent years,a new class of interatomic potentials known as magnetic machine-learning interatomic potentials(magnetic MLIPs)has emerged.These MLIPs combine the computational efficiency,in terms of CPU time,of empirical potentials with the accuracy of DFT calculations.In this review,our focus lies on providing a comprehensive summary of the interatomic interaction models developed specifically for investigating magnetic materials.We also delve into the various problem classes to which these models can be applied.Finally,we offer insights into the future prospects of interatomic interaction model development for the exploration of magnetic materials.

关键词： materials. interaction empirical

Is Veillonella a unique marker of physical exercise?Commentary on:"Is physical performance(in mice)increased by Veillonella atypica or decreased by Lactobacillus bulgaricus?"

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Journal of Sport and Health Science 2024年第5期13卷 682-684页

作者： Viktor Bielik ivan Hric riadh Hammami Department of Biological and Medical Science Faculty of Physical Education and SportComenius University in BratislavaBratislava 81469Slovakia Department of Molecular Biology Faculty of Natural SciencesComenius University in BratislavaBratislava 84215Slovakia Biomedical research Center Institute of Clinical and Translational ResearchSlovak Academy of SciencesBratislava 84505Slovakia School of Nutrition Sciences Faculty of Health SciencesUniversity of OttawaOttawaON K1N 6N5Canada Department of Biochemistry Microbiology and ImmunologyFaculty of MedicineUniversity of OttawaOttawaON K1N 6N5Canada

In 2020,Kostic1 published commentary on the bacterial genus Veillonella associated with the interaction between the intestinal microbiota and skeletal muscle.Since then,novel perspectives on the bidirectional gut-muscle communication axis have gained a lot of attention.The purpose of this commentary is to explore some of the challenging issues presented in Scheiman et al.

关键词： al. skeletal gained

Search for microglia-specific peptides:advances in the discovery toolbox

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Neural regeneration research 2025年第2期20卷 471-472页

作者： ivan Sarabia Kyle M.Koss Department of Surgery University of ArizonaTucsonAZUSA

Uncontrolled and chronic inflammatory states in the central nervous system(CNS)are the hallmark of neurodegenerative pathology and every injury or stroke-related insult.The key mediators of these neuroinflammatory states are glial cells known as microglia,the resident immune cell at the core of the inflammatory event,and astroglia,which encapsulate inflammatory insults in proteoglycan-rich scar tissue.This gliotic scar blocks significant portions of healthy axonal networking,preventing regeneration.Since most neuroinflammation is exclusively based on the responses of said microglia,their phenotypes are suggested to follow those of macrophages;M1 and M2 are opposites of pro-and anti-inflammation.However,microglial phenotypes have been identified to be on an inflammatory spectrum encompassing developmental,homeostatic,and reparative behaviors as opposed to their ability to affect devastating cell death cascades and scar tissue formation.

关键词： inflammation pathology death

Emerging and multifaceted potential contributions of polyphenols in the management of type 2 diabetes mellitus

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World Journal of Diabetes 2024年第2期15卷 154-169页

作者： Ileana González Cristian Lindner ivan Schneider Erik Diaz Miguel Angel Morales Armando rojas Biomedical research Laboratories Faculty of MedicineCatholic University of MauleTalca 34600000Chile Department of radiology Faculty of MedicineUniversity of ConcepciónConcepción 4030000Chile Centre of Primary Attention South Metropolitan Health ServiceSantiago 3830000Chile Faculty of Medicine Catholic University of MauleTalca 3460000Chile Molecular and Clinical Pharmacology Program Institute of Biomedical SciencesUniversity of ChileSantiago 8320000Chile

Type 2 diabetes mellitus(T2DM)is recognized as a serious public health concern with a considerable impact on human life,long-term health expenditures,and substantial health losses.In this context,the use of dietary polyphenols to prevent and manage T2DM is widely documented.These dietary compounds exert their beneficial effects through several actions,including the protection of pancreatic islet β-cell,the antioxidant capacities of these molecules,their effects on insulin secretion and actions,the regulation of intestinal microbiota,and their contribution to ameliorate diabetic complications,particularly those of vascular origin.In the present review,we intend to highlight these multifaceted actions and the molecular mechanisms by which these plant-derived secondary metabolites exert their beneficial effects on type 2 diabetes patients.

关键词： Polyphenols Antioxidants Oxidative stress Type 2 diabetes mellitus Health benefits