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Journal of Civ.l Engineering and Architecture 2015年第4期9卷 401-409页

作者： Natalia v. Dursenev. andrey v. indeykin Inna O. Kuznetsov. Alexander M. Uzdin Maria Fedorov. Theoretical Mechanics Department St-Petersburg State Railway Transport University St-Petersburg 190031 Russia Faculty of Mathematics and Mechanics St-Petersburg State University St-Petersburg 191119 Russia

The peculiarities of calculating isolated structures with spherical bearings are analyzed in this paper. Some of peculiarities are caused by the lack of data at the moment when engineering solutions had to be made, Other peculiarities are connected with physical peculiarities of the dev.ce behav.our. To prov.de the analysis of structure hehav.our under the condition of the lack of input information, two types of design models of seismic protection dev.ces were considered. They are the dampers linearization and the modelling of real dampers by dry friction ones. The dampers linearization makes it possible to use the existing software for calculating linear strongly-damped systems. To calculate structures with dry friction dampers, a new software was worked out. In this case, the structure is described as a piecewise-linear system of a relay-type. The inv.stigations of the structure oscillations take into account both horizontal and v.rtical components of earthquake input. Under this condition, horizontal oscillation equations of structures are the MaRie-Hill ones. The input and structure parameters which caused the structure instability are estimated. To exclude the structure instability, high damping dev.ces should be used. These methods were used for seismic resistant analysis of bridges with spherical bearings and hydraulic dampers applied in Sochi.

关键词： Seismic isolation spherical bearings hydraulic dampers calculations.

Merging bound states in the continuum in an open acoustic resonator

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem S.Pilipchuk Sibo Huang Chen Shen Almas F.Sadreev.Yong Li andrey E.Miroshnichenko School of Physics and Electronic Sciences East China Normal University Institute of Acoustics Tongji University L.v.Kirensky Institute of Physics Department of Mechanical Engineering Rowan University School of Engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is v.ry sensitiv. to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are sustained in a single coupled wav.guide-resonator *** v.rying the height and length of the resonator,these two BICs mov. toward each other and merge into a single one at a critical *** to an indiv.dual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-lev.l approximations of the effectiv. nonHermitian ***,we present direct experimental demonstrations of the mov.ng and merging of BICs in a coupled 3D wav.guide-resonator,which are ev.denced by the v.nishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

Studies of ultrasonic dehydration efficiency

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Journal of Zhejiang Univ.rsity-Science A(Applied Physics & Engineering) 2011年第4期12卷 247-254页

作者： v.adimir N. KHMELEv.andrey v. SHALUNOv.Roman v. BARSUKOv.Denis S. ABRAMENKO andrey N. LEBEDEv Biysk Technological Institute (Branch) Altai State Technical Univ.rsity

The aim of this inv.stigation was to define the effectiv.ness of non-contact drying using ultrasonic v.brations. Disk radiators were used for carrying out experiments, and a special drying chamber was designed to prov.de resonant amplification of ultrasonic v.brations (from 130 to 150 dB). Drying of ginseng and other v.getables demonstrated that the application of ultrasonic v.brations reduced power inputs by 20% in comparison with conv.ctiv. drying. It also led to a decrease of 6% in final moisture content, if the duration of drying was constant. The lev.l of intensification of ultrasonic drying was high (up to 50 g for 1 kg of drying material), which helped to lower the temperature of the drying agent and improv. the quality of the dried products.

关键词： Drying Ultrasound v.bration system Drying chamber Processing (treatment) of agricultural products

Age of maturation and behav.oral tactics in male yellow ground squirrel Spermophilus fulv.s during mating season

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Current Zoology 2014年第6期60卷 700-711页

作者： Nina A. v.SILIEv. Ekaterina v. PAv.Ov. Sergey v. NAIDENKO andrey v.TCHABOv.KY A.N. Sev.rtsov.Institute of Ecology and Ev.lution Russian Academy of Sciences 33 Leninsky pr. Moscow 119071 Russia

Life-history theory predicts that in hibemators age of maturation is related positiv.ly to body size and negativ.ly to the duration of activ. season abov.ground. Yellow souslik is a large-sized ground squirrel with long hibernation, which suggests late maturation. We used four-year field observ.tions of marked indiv.duals to determine the age of maturation in males through analysis of age-dependent v.riation in body size, mass, androgen status, timing of spring emergence, ranging patterns and social behav.or during the mating season. Yearling males were smaller, lighter, had lower lev.l of fecal testosterone, emerged later and had smaller home ranges than older males. Social activ.ty and the number of females encountered did not differ between age classes. After the second hibernation none of the studied parameters v.ried with age. Cluster analysis rev.aled two behav.oral tactics：＂activ.＂ males （adults only） emerged earlier, ranged more widely, initiated more contacts, encountered more females and were heav.er than ＂passiv.＂ males （both yearling and adult）. Thus, males of S. fulv.s reached adult size and matured after two hibernations, which is relativ.ly fast for such a big species with short activ. period. Indirect ev.dence for copulations and high v.riation among yearlings in all parameters suggest that some of them might successfully compete with adults. Activ. tactic of wandering and searching for females is energetically costly, and probably only adult males in good physical condition can afford it, whereas passiv. tactic of residing is energy sav.ng and good for adults in poor condition and for yearlings that are continuing to grow.

关键词： Age of maturation Mating system Reproductiv. tactics Ground squirrel Spermophilusfulv.s

Nucleation of methane hydrate and ice in emulsions of water in crude oils and decane under non-isothermal conditions

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Chinese Journal of Chemical Engineering 2019年第3期27卷 668-676页

作者： andrey S. Stoporev.Lidiya I. Sv.rov.kaya Larisa A. Strelets Lubov. K. Altunina Galina v. v.llev.ld Tamara D. Karpov. Tatyana v. Rodionov. andrey Yu. Manakov Nikolaev.Institute of Inorganic Chemistry SB RAS Nov.sibirsk State Univ.rsity Institute of Petroleum Chemistry

Achiev.ble supercooling for the formation of methane hydrate from water emulsions was studied in sev.n different crude oils and in decane. The experiments were performed under constant rate cooling from + 20 to-15 °C and a pressure of methane of 12 MPa. It was demonstrated that the shapes and positions of the resulting surv.v.l curv.s depend on the density, v.scosity and dispersiv. power of oil samples used in the experiments, as well as on the degree of oil oxidation. In addition, results of the experiments on ice freezing under the same emulsions are presented. The results obtained in the work allowed us to discuss the possibility and features of primary and secondary nucleation of the hydrate and ice in the systems under consideration.

关键词： Methane hydrate Crude oil Oil dispersiv. system Nucleation

Comparison of diode laser continuous wav. and in soft tissue surgery using pulsed modes in v.tro

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Frontiers of Optoelectronics 2015年第2期8卷 212-219页

作者： andrey v. BELIKOv.Alexei v. SKRYPNIK Ksenia v. SHATILOv. Saint-Petersburg National Research Univ.rsity of Information Technologies Mechanics and Optics (ITMO University) Saint-Petersburg 197101 Russia

In this study, the interaction between diode laser radiation and chicken soft tissue was studied in v.tro by a high-speed digital v.deo camera. We used a diode laser with a wav.length of （980 ±10）nm and av.rage power of 10 W. The diode laser was operated in continuous wav. （CW） and pulsed modes. In CW mode, the av.rage laser radiation power was 10 W; in pulsed mode, the av.rage laser radiation power was I0 W and the peak power was 20 W. Diode laser radiation was deliv.red to soft tissue （chicken meat） using a quartz optical fiber with either a clear distal end （clear tip） or a distal end containing an optothermal conv.rter （hot tip）. Application of the diode laser in pulsed mode resulted in crater depths and areas of collateral damage in soft tissue about 1.6 times greater than those observ.d in CW mode at treatment with the clear tip. Significant differences in the crater depth and collateral damage width of chicken meat were not found after hot-tip treatment with the diode laser in CW and pulsed modes. Soft tissue treated with the hot tip showed crater depths about 3.4 times greater than those observ.d after treatment with the clear tip. Hot tip treatment further resulted in collateral damage widths about 2.7 times lower than those obtained after treatment with the clear tip.

关键词： diode laser thermo-optically powered sur-gery hot tip surgery laser surgery soft tissue

Decomposition of carbon dioxide hydrate in the samples of natural coal with different degrees of metamorphism

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Chinese Journal of Chemical Engineering 2020年第2期28卷 492-501页

作者： v.acheslav.G. Smirnov.v.leriy v. Dyrdin andrey Yu. Manakov.Zinfer R. Ismagilov Kuzbass State Technical Univ.rsity Vesennaya str.28Kemerovo 650000Russian Federation Nikolaev.Institute of Inorganic Chemistry SB RAS Ac.Lavrentiev ave.3Novosibirsk 630090Russian Federation Nov.sibirsk State Univ.rsity Pirogov Str.2Novosibirsk 630090Russian Federation Institute of Coal Chemistry and Material Science SB RAS Sovetsky ave.18Kemerovo 650000Russian Federation

Methane and carbon dioxide hydrates are one of the possible forms in which these gases exist in natural coal(for more detailed discussion see Refs [1,2]). In this work, the decomposition of carbon dioxide hydrate in fiv. samples of natural coal differing from each other in metamorphism degree was inv.stigated experimentally. Carbon dioxide hydrate dispersed in coals was synthesized from water adsorbed in these coals. During a linear temperature rise in an autoclav. with the coal + hydrate sample the hydrate decomposition manifests itself as a step of increase in gas pressure, accompanied by a decrease/stabilization of the temperature of coal sample. The dependencies of the amount of hydrate formed on initial coal humidity and on gas pressure during hydrate formation were studied. It was demonstrated that each coal sample is characterized by its own humidity threshold below which hydrate formation in natural coal is impossible. With an increase in gas pressure, the amount of water transformed into hydrate increases. For the studied coal samples, the decomposition of carbon dioxide hydrates proceeds within a definite temperature and pressure range, and this range is close to the curv. of phase equilibrium for bulk hydrate.

关键词： Gas hydrate Carbon dioxide Coal Coal rank Phase transformation Coal bed gas

Autoimmunity in acute ischemic stroke and the role of bloodbrain barrier: the dark side or the light one?

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Frontiers of Medicine 2019年第4期13卷 420-426页

作者： Nikolay v. Tsygan Alexandr P. Trashkov.Igor v. Litv.nenko v.ktoriya A. Yakov.ev. Alexandr v. Ryabtsev.andrey G. v.siliev.Leonid P. Churilov Department of Molecular and Radiation Biophysics B.P. Konstantinov Petersburg Nuclear Physics Institute Gatchina Leningrad Region 188300 Russian Federation Department of Nerv.us Diseases S.M. Kirov Military Medical Academy Saint Petersburg 194044 Russian Federation Department of Experimental Pharmacology I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry Saint Petersburg 194223 Russian Federation Department of Pathological Physiology with the Course of Immunopathology Saint Petersburg State Pediatric Medical University Saint Petersburg Russian Federation Department of Pathology Laboratory of the Mosaic of Autoimmunity Saint Petersburg State University Saint Petersburg 199034 Russian Federation

This article presents a synopsis of the current data on the mechanisms of blood-brain barrier (BBB) alteration and autoimmune response in acute ischemic stroke. Most researchers confirm the relationship between the sev.rity of immunobiochemical changes and clinical outcome of acute ischemic stroke. Ischemic stroke is accompanied by aseptic inflammation, which alters the brain tissue and exposes the co-stimulatory molecules of the immune system and the neuronal antigens. To date, BBB is not considered the border between the immune system and central nerv.us system, and the local immune subsystems are found within and behind the BBB. BBB disruption contributes to the leakage of brain autoantigens and induction of secondary autoimmune response to neuronal antigens and long-term inflammation. Glymphatic system function is altered and jeopardized both in hemorrhagic and ischemic stroke types. The receptors of innate immunity (toll-like receptor-2 and toll-like receptor-4) are also inv.lv.d in acute ischemia-reperfusion injury. Immune response is related to the key processes of blood clotting and fibrinolysis. At the same time, the stroke-induced immune activ.tion may promote reparation phenomena in the brain. Subsequent research on the reduction of the acute ischemic brain injury through the target regulation of the immune response is promising.

关键词： stroke blood-brain barrier autoimmunity innate immunity inflammation cell death

Regenerativ. medicine of pancreatic islets

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World Journal of Gastroenterology 2020年第22期26卷 2948-2966页

作者： Irina v.Arutyunyan Timur Kh Fatkhudinov.andrey v.Makarov.andrey v.Elchaninov.Gennady T Sukhikh National Medical Research Center for Obstetrics Gynecology and Perinatology named after Academician V.I.Kulakov of Ministry of Healthcare of Russian FederationMoscow 117997Russia Research Institute of Human Morphology Moscow 117418Russia Peoples Friendship Univ.rsity of Russia Moscow 117198Russia Pirogov.Russian National Research Medical Univ.rsity Ministry of Healthcare of the Russian FederationMoscow 117997Russi

The pancreas became one of the first objects of regenerativ. medicine,since other possibilities of dealing with the pancreatic endocrine insufficiency were clearly *** number of people liv.ng with diabetes mellitus is currently approaching half a billion,hence the crucial relev.nce of new methods to stimulate regeneration of the insulin-secretingβ-cells of the islets of *** restrictions on the islet regeneration are v.ry tight;nev.rtheless,the islets are capable of physiological regeneration v.aβ-cell self-replication,direct differentiation of multipotent progenitor cells and spontaneousα-toβ-orδ-toβ-cell conv.rsion(trans-differentiation).The existing preclinical models ofβ-cell dysfunction or ablation(induced surgically,chemically or genetically)hav. significantly expanded our understanding of reparativ. regeneration of the islets and possible ways of its *** ultimate goal,sufficient lev.l of functional activ.ty ofβ-cells or their substitutes can be achiev.d by two prospectiv. broad strategies:β-cell replacement andβ-cell ***“regeneration”strategy aims to maintain a preserv.d population ofβ-cells through in situ exposure to biologically activ. substances that improv.β-cell surv.v.l,replication and insulin secretion,or to ev.ke the intrinsic adaptiv. mechanisms triggering the spontaneous non-β-toβ-cell ***“replacement”strategy implies transplantation ofβ-cells(as non-disintegrated pancreatic material or isolated donor islets)orβ-like cells obtained ex v.v. from progenitors or mature somatic cells(for example,hepatocytes orα-cells)under the action of small-molecule inducers or by genetic *** believ. that the huge v.lume of experimental and clinical studies will finally allow a safe and effectiv. solution to a seemingly simple goal-restoration of the functionally activ.β-cells,the innermost hope of millions of people globally.

关键词： Pancreas Islets of langerhans β-cells Regeneration Replacement Transplantation Reprogramming

Autonomous UAv.3D trajectory optimization and transmission scheduling for sensor data collection on unev.n terrains

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Defence Technology（防务技术） 2023年第12期30卷 154-160页

作者： andrey v.Sav.in Satish C.v.rma Wei Ni School of Electrical Engineering and Telecommunications University of New South WalesSydneyAustralia Data61 CSIROCanberraACT2601Australia

This paper considers a time-constrained data collection problem from a network of ground sensors located on unev.n terrain by an Unmanned Aerial v.hicle(UAv.,a typical Unmanned Aerial System(UAS).The ground sensors harv.st renewable energy and are equipped with batteries and data *** ground sensor model takes into account sensor data buffer and battery *** asymptotically globally optimal method of joint UAv.3D trajectory optimization and data transmission schedule is *** dev.loped method maximizes the amount of data transmitted to the UAv.without losses and too long delays and minimizes the propulsion energy of the *** dev.loped algorithm of optimal trajectory optimization and transmission scheduling is based on dynamic *** simulations demonstrate the effectiv.ness of the proposed algorithm.

关键词： Unmanned aerial system UAS Unmanned aerial v.hicle UAv Wireless sensor networks UAS-Assisted data collection 3D trajectory optimization Data transmission scheduling