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spatiotemporal continuum generation in polariton waveguides

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Light(science & Applications) 2019年第1期8卷 1117-1127页

作者： Paul M.Walker Charles E.Whittaker dmitry V.skryabin Emiliano Cancellieri Ben Royall Maksym sich Ian Farrer David A.Ritchie Maurice s.skolnick dmitry N.Krizhanovskii Department of Physics and Astronomy University of SheffieldSheffield S37RHUK Department of Physics University of BathBath BA27AYUK ITMO University Kronverksky Avenue 49St.Petersburg 197101Russia Department of Physics Lancaster UniversityLancaster LA14YBUK Department of Electronic and Electrical Engineering University of SheffieldSheffield S37HQUK Cavendish Laboratory University of CambridgeCambridge CB30HEUK

We demonstrate the generation of a spatiotemporal optical continuum in a highly nonlinear exciton–polariton waveguide using extremely low excitation powers(2-ps,100-W peak power pulses)and a submillimeter device suitable for integrated optics *** observe contributions from several mechanisms over a range of powers and demonstrate that the strong light–matter coupling significantly modifies the physics involved in all of *** experimental data are well understood in combination with theoretical *** results are applicable to a wide range of systems with linear coupling between nonlinear oscillators and particularly to emerging polariton devices that incorporate materials,such as gallium nitride and transition metal dichalcogenide monolayers that exhibit large light–matter coupling at room *** open the door to low-power experimental studies of spatiotemporal nonlinear optics in submillimeter waveguide devices.

关键词： millimeter waveguide optics

Ecological Niche Modelling Reveals the Peculiarities of Ecological Disjunction Between Two sympatric Racerunners in Kazakhstan:Eremias lineolata(Nikolsky,1897)and Eremias scripta(strauch,1867)

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Asian Herpetological Research 2023年第2期14卷 123-137页

作者： Marina A.CHIRIKOVA dmitry V.MALAKHOV Institute of Zoology Committee of Scientific Ministry of Science and Higher EducationAl-Farabi 93 AkademgorodokAlmaty 050060Kazakhstan

The ecological-niche models for two sympatric species,Eremias lineolata(Nikolsky,1897)and Eremias scripta(strauch,1867),reveal evidence of spatial and temporal disjunction in the actual niches of both *** lineolata demonstrates a wide range of adaptations and,at the same time,has a greater need for winter precipitation and minimal temperature than *** explanations for the thermal diversity of both species are *** variables(monthly temperatures,monthly solar radiation,etc.)are traditionally important for ectotherm ***,as many as half of the key variables in both species are related to different aspects of environmental water balance(precipitation,air humidity,vapor pressure).There are several ways in which moisture may impact the lizard’s life *** humidity is related to soil temperature and may be important during winter *** summer,soil humidity may support successful *** during the warm months is a key factor in maintaining the moisture content of the *** winter,snow cover provides a better thermal balance of the soil’s top layers where winter shelters are *** niche modeling(ENM)is an interdisciplinary approach combining the geographical,climatic,ecological,and biological aspects of the wellbeing of *** interdisciplinary approach lifts biological studies onto a new,integrative level,providing a comprehensive view on species biology and answering the questions that might not be answered if the traditional methods for studying animals were used alone.

关键词： ecology Kazakhstan niche modelling racerunners species distribution

Experimental investigations of internal energy dissipation during fracture of fiber-reinforced ultra-high-performance concrete

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Frontiers of structural and Civil Engineering 2019年第1期13卷 190-200页

作者： Eric N.LANDIs Roman KRAVCHUK dmitry LOsHKOV Department of Civil &Environmental Engineering University of MaineOronoME 04469USA

split-cylinder fracture of fiber-reinforced ultra-high-performance concrete (UHPC)was examined using two complementary techniques:X-ray computed tomography (CT)and acoustic emission (AE).Fifty-mm-diameter specimens of two different fiber types were scanned both before and after load *** the CT images,fiber orientation was evaluated to establish optimum and pessimum specimen orientations,at which fibers would have maximum and minimum effect,*** expected,fiber orientation affected both the peak load and the toughness of the specimen,with the optimum toughness being between 20% and 30%higher than the *** AE energy was also affected *** CT scans of the specimens were used to measure internal damage. Damage was quantified in terms of internal energy dissipation due to both matrix cracking and fiber pullout by using calibration measurements for *** results showed that fiber pullout was the dominant energy dissipation mechanism;however,the sum of the internal energy dissipation measured amounted to only 60% of the total energy dissipated by the specimens as measured by the net work of *** is postulated that localized compaction of the UHPC matrix as well as internal friction between fractured fragments makes up the balance of internal energy dissipation.

关键词： ultra-high-performance concrete concrete fracture X-ray computed tomography acoustic emission

Unsteady bio-fluid dynamics in flying and swimming

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Acta Mechanica sinica 2017年第4期33卷 663-684页

作者： Hao Liu dmitry Kolomenskiy Toshiyuki Nakata Gen Li Graduate school of Engineering Chiba University 1-33Yayoi-cho Inage-ku Chiba Japan shanghai-Jiao Tong University and Chiba UniversityInternational Cooperative Research Centre (sJTU-CU ICRC) Shanghai 200240 China

Flying and swimming in nature present sophisticated and exciting ventures in biomimetics, which seeks sustainable solutions and solves practical problems by emulating nature＇s time-tested patterns, functions, and strategies. Bio-fluids in insect and bird flight, as well as in fish swimming are highly dynamic and unsteady; however, they have been studied mostly with a focus on the phenomena associated with a body or wings moving in a steady flow. Characterized by unsteady wing flapping and body undulation, fluid-structure interactions, flexible wings and bodies, turbulent environments, and complex maneuver, bio-fluid dynamics normally have challenges associated with low Reynolds number regime and high unsteadiness in modeling and analysis of flow physics. In this article, we review and highlight recent advances in unsteady bio-fluid dynamics in terms of leading-edge vortices, passive mechanisms in flexible wings and hinges, flapping flight in unsteady environments, and micro-structured aerodynamics in flapping flight, as well as undulatory swimming, flapping-fin hydrodynamics, body–fin interac-tion, C-start and maneuvering, swimming in turbulence,collective swimming, and micro-structured hydrodynamics in swimming. We further give a perspective outlook on future challenges and tasks of several key issues of the field.

关键词： swimming wings unsteady turbulence hydrodynamics turbulent body kinematics vortex street

Transformation of the TiNi Alloy Microstructure and the Mechanical Properties Caused by Repeated B2-B190' Martensitic Transformations

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Acta Metallurgica sinica(English Letters) 2015年第10期28卷 1230-1237页

作者： Anna Churakova dmitry Gunderov Alexander Lukyanov Niklas Nollmann Institute of Molecule and Crystal Physics RAs Ufa state Aviation Technical University Institute of Materials Physics University of Münster

The influences of thermal cycling treatment in the temperature range of B2-B19 martensitic transformations（-150 to 150 °C） on the Ti Ni alloy structure and properties were studied. Different states named the initial coarse-grained（CG） state, the ultrafine-grained（UFG） state after ECAP（with a grain size of 200 nm）, the state after ECAP and cold upsetting by 30% were considered. The results show that the microhardness and the strength increase in all the three *** to the XRD analysis, a more significant increment in the dislocation density, resulting from thermal cycling, is observed in the UFG alloy than in the CG alloy.

关键词： Thermal cycling TiNi alloy Equal-channel angular pressing Martensitic transformation

Development of necrotizing enterocolitis after blood transfusion in very premature neonates

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World Journal of Pediatrics 2023年第1期19卷 68-75页

作者： Travis L.Odom Jessica Eubanks Nusiebeh Redpath Erica Davenport dmitry Tumin Uduak s.Akpan Department of Pediatrics University of Texas Health Sciences Campus7703 Floyd Curl DriveSan AntonioTX 78229-3900USA Department of Pediatrics Brody School of Medicine at EastCarolina UniversityGreenvilleNCUSA ECU Health Medical Center GreenvilleNCUSA

Background Prior studies report conflicting evidence on the association between packed red blood cell(PRBC)transfu-sions and necrotizing enterocolitis(NEC),especially in early weeks of life where transfusions are frequent and spontaneous intestinal perforation can mimic *** primary objective of this study was to evaluate the association between PRBC transfusions and NEC after day of life(DOL)14 in very premature *** A retrospective cohort analysis of very premature neonates was conducted to investigate association between PRBC transfusions and NEC after DOL *** endpoints were PRBC transfusions after DOL 14 until the date of NEC diagnosis,discharge,or *** ranked-sum and Fisher's exact tests,Cox proportional hazards regression,and Kaplan-Meier curves were used to analyze *** Of 549 premature neonates,186(34%)received transfusions after DOL 14 and nine(2%)developed NEC(median DOL=38;interquartile range=32-46).Of the nine with NEC after DOL 14,all were previously transfused(Psis of patients from DOL 10 onward included five additional patients who developed NEC between DOL 10 and DOL 14,and the hazard of NEC increased by a factor of nearly six after PRBC transfusion(hazard ratio=5.76,95%confidence interval=1.02-32.7;P=0.048).Conclusions Transfusions were strongly associated with NEC after DOL *** studies are needed to determine if restrictive transfusion practices can decrease incidence of NEC after DOL 14.

关键词： Necrotizing enterocolitis Packed red blood cells Transfusions Very low birth weight infants

Operating limits and features of direct air capture on K_(2)CO_(3)/ZrO_(2) composite sorbent

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Chinese Journal of Chemical Engineering 2022年第6期35卷 11-20页

作者： Vladimir s.Derevschikov Janna V.Veselovskaya Anton s.shalygin dmitry A.Yatsenko Andrey Z.sheshkovas Oleg N.Martyanov Boreskov Institute of Catalysis sB RAs Akademika Lavrentieva Av.5630090 NovosibirskRussia Novosibirsk state University Pirogova Str.1630090 NovosibirskRussia

Potassium carbonate-based sorbents are prospective materials for direct air capture(DAC).In the present study,we examined and revealed the influence of the temperature swing adsorption(TsA)cycle conditions on the CO_(2) sorption properties of a novel aerogel-based K_(2)CO_(3)/ZrO_(2) sorbent in a DAC *** was shown that the humidity and temperature drastically affect the sorption dynamic and sorption capacity of the *** a temperature at the sorption stage was 29℃ and a water vapor pressure P_(H2O) in the feed air was 5.2 mbar(1 bar=105 Pa),the composite material demonstrated a stable CO_(2) sorption capacity of 3.4%(mass).An increase in sorption temperature leads to a continuous decrease in the CO_(2) absorption capacity reaching a value of 0.7%(mass)at T=80℃.The material showed the retention of a stable CO_(2) sorption capacity for many cycles at each temperature in the *** PH2O in the inlet air from 5.2 to 6.8 mbar leads to instability of CO_(2) sorption capacity which decreases in the course of 3 consecutive TsA cycles from 1.7%to 0.8%(mass)at T=29℃.A further increase in air humidity only facilitates the deterioration of the CO_(2) sorption capacity of the material.A possible explanation for this phenomenon could be the filling of the porous system of the sorbent with solid reaction products and an aqueous solution of potassium salts,which leads to a significant slowdown in the CO_(2) diffusion in the composite sorbent *** investigate the regeneration step of the TsA cycle in situ,the macro ATRFTIR(attenuated total reflection Fourier-transform infrared)spectroscopic imaging was applied for the first *** was shown that the migration of carbonate-containing species over the surface of sorbent occurs during the thermal regeneration stage of the TsA *** movement of the active component in the porous matrix of the sorbent can affect the sorption characteristics of the composite *** revealed features make it possible

关键词： Zirconia aerogel Potassium carbonate Carbon dioxide Direct air capture Fourier-transform infrared spectroscopic imaging

Orbits of Real semisimple Lie Groups on Real Loci of Complex symmetric spaces

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Acta Mathematica sinica,English series 2018年第3期34卷 439-453页

作者： stéphanie CUPIT-FOUTOU dmitry A.TIMAsHEV Ruhr-Universitat Bochum Fakultat fiir Mathematik D-44780 Bochum Germany Lomonosov Moscow state University Faculty of Mechanics and Mathematics Department of Higher Algebra 119991 Moscow Russia

Let G be a complex semisimple algebraic group and X be a complex symmetric homogeneous G-variety. Assume that both G, X as well as the G-action on X are defined over real *** G（R） acts on X（R） with finitely many orbits. We describe these orbits in combinatorial terms using Galois cohomology, thus providing a patch to a result of Borel and Ji.

关键词： semisimple group symmetric space real point orbit Galois cohomology

Features of the long-term transformation of the Krasnodar reservoir,near the mouth of the Kuban River,Russia

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Journal of Geographical sciences 2021年第12期31卷 1895-1904页

作者： POGORELOV Anatoly LAGUTA Andrey KIsELEV Evgeny LIPILIN dmitry Kuban state University Krasnodar 350040Russia Aerogematica LLC Krasnodar 350063Russia Kuban state Agrarian University Named after I.T.Trubilin Krasnodar 350044Russia Tuapse Branch of the Russian state Hydrometeorological University Krasnodar RegionTuapse 352800Russia

The article considers the long-term(1941-2018)transformation of the Krasnodar valley reservoir,the largest in the North *** main functions of the Krasnodar reservoir are irrigation of rice systems and flood protection of land in the Krasnodar reservoir region and the Republic of *** to topographic maps,Landsat satellite images(1974-2018)and field observations(2016-2018),four stages of transformation of the floodplain reservoir are *** selected stages are characterized by both natural causes(the transformation of the filling deltas into the extended deltas,etc.)and man-made causes(runoff diversions in the delta areas,etc.).The key factor of transformation is the formation of deltas of rivers flowing into the *** of the selected stages,against the background of a gradual reduction in the area and volume of the reservoir,is characterized by the peculiarities of the formation of river deltas with the formation of genetically homogeneous sections of delta *** the period of operation of the reservoir,the delta of the main Kuban River moved up to 32.4 km and took away an area of 35.4 km^(2) of the *** the formation of the deltas of the Kuban and Belaya rivers,a bridge was formed on the Krasnodar *** evolution of the delta regions led to the division of the reservoir into two autonomous *** total area of the delta regions was 85.9 km^(2) by 2018,i.e.,21% of the initial area of the *** transformation of the Krasnodar reservoir leads to a decrease in its regulated volume and gradual degradation.

关键词： Krasnodar reservoir sedimentation siltation transformation delta formation Landsat