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Holographic dark energy in non-conserved gravity theory

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Communications in Theoretical Physics 2024年第4期76卷 126-133页

作者： H r Fazlollahi Institute of Gravitation and Cosmology Peoples Friendship University of Russia(RUDN University)6 Miklukho-Maklaya StMoscow117198Russia

recently, reconsidering the rastall idea T_(μ;νν)^(v)=α_(,μ) through relativistic thermodynamics gives a new form for the scalar field α which led us to construct modern modified theory of gravity debugged ‘non-conserved gravity theory’ Fazlollahi 2023 Euro. Phys. J. C 83 923. This theory unlike other modified theories of gravity cannot directly explain the current acceleration expansion in the absence of the cosmological constant and or existence of other forms of dark energy. Hence, in this study we have reinvestigated holographic dark energy Ρ_(X)~H^(2) in the non-conserved theory of gravity. In this context, the density and pressure of dark energy depend on the non-conserved term and density of the dust matter field. As shown, due to non-conservation effects on large-scale structures, unlike the original holographic model, our model onsets an acceleration epoch for the current Universe satisfies observations. Moreover, the interaction and viscous scenarios are studied for this model.

关键词： non-conserved gravity covariant form of thermodynamics holographic dark energy

Cross-method Analysis of Corotation radii Data Set for Spiral Galaxies

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research in Astronomy and Astrophysics 2024年第7期24卷 98-113页

作者： v.S.Kostiuk A.A.Marchuk A.S.Gusev Sternberg Astronomical Institute Lomonosov Moscow State University Central (Pulkovo) Astronomical Observatory Russian Academy of Sciences Saint Petersburg State University

A corotation radius is a key characteristic of disk galaxies that is essential to determine the angular speed of the spiral structure Ωp, and therefore understand its nature. In the literature, there are plenty of methods to estimate this value, but do these measurements have any consistency? In this work, we collected a data set of corotation radius measurements for 547 galaxies, 300 of which had at least two values. An initial analysis reveals that most objects have rather inconsistent corotation radius positions. Moreover, a significant fraction of galactic disks is distinguished by a large error coverage and almost uniform distribution of measurements. These findings do not have any relation to spiral type, Hubble classification, or presence of a bar. Among other reasons, obtained results could be explained by the transient nature of spirals in a considerable part of galaxies. We have made our collected data sample publicly available, and have demonstrated on one example how it could be useful for future research by investigating a winding time value for a sample of galaxies with possible multiple spiral arm patterns.

关键词： galaxies: fundamental parameters galaxies: kinematics and dynamics galaxies: structure

Crafting chirality in three dimensions via a novel fabrication technique for bound states in the continuum metasurfaces

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Light(Science & Applications) 2024年第3期13卷 390-392页

作者： Zaid Haddadin Anna My Nguyen Lisa v.Poulikakos Department of Electrical&Computer Engineering University of California San DiegoLa JollaCAUSA Department of Mechanical&Aerospace Engineering University of California San DiegoLa JollaCAUSA Program of Materials Science&Engineering University of California San DiegoLa JollaCAUSA

An additional deposition step was added to a multi-step electron beam lithographic fabrication process to unlock the height dimension as an accessible parameter for resonators comprising unit cells of quasi-bound stat... 详细信息

关键词： dimensions dimension intrinsic

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

关键词： materials interaction empirical

Why lowland riparian trees are difficult to use for streamflow reconstruction

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Journal of Forestry research 2024年第3期35卷 219-230页

作者： Xiaomei Peng Shengchun Xiao Bao Yang Quanyan Tian vladimir v.Shishov Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000People's Republic of China School of Geography and Ocean Science Nanjing UniversityNanjing 210023People's Republic of China Institute of Fundamental Biology and Biotechnology Siberian Federal UniversityKrasnoyarskRussia 660041

Existing streamflow reconstructions based on tree-ring analysis mostly rely on species from upland,mainly montane areas,while lowland species(generally plain)areas are rarely *** limits the understanding of streamflow change history in the lowlands,which is an important basis for water resource *** study focused on Populus euphratica stands located along the main stream,eastern and western tributaries in the lower reaches of the Heihe river basin(Hrb),in arid northwestern *** investigated how streamflow regulation interferes with ripar-ian trees in lowlands when they used for streamflow ***-ring width chronologies were developed and analyzed in conjunction with meteorological and hydrologic observation *** results show streamflow regulation leads in sharp fluctuations in the streamflow allocation between the eastern tributaries and western *** resulted in instability of the correlation between streamflow at the two tributaries and at the Zhengyixia hydrologic station,with corresponding fluctuations in radial growth of poplar trees on the banks of the two tributaries and at the *** regulation altered the natural patterns of seasonal streamflow below the station,changing the time window of poplar *** study provides useful insight into tree-ring width based streamflow reconstruction in the lowlands.

关键词： Tree-ring width-Dendrochronology Populus euphratica The Ejina Oasis Streamflow

Prompt neutron emission in ^(250)No spontaneous fission associated with ground and isomeric state decays

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Chinese Physics C 2024年第6期48卷 112-117页

作者： r.S.Mukhin A.v.Isaev A.v.Andreev M.L.Chelnokov v.I.Chepigin H.M.Devaraja I.N.Izosimov A.A.Kuznetsova O.N.Malyshev A.G.Popeko Yu.A.Popov A.rahmatinejad B.Sailaubekov T.M.Shneidman E.A.Sokol A.I.Svirikhin M.S.Tezekbayeva M.A.Bychkov A.v.Yeremin O.Dorvaux B.Gall K.Kessaci K.Hauschild A.Lopez-Martens Joint Institute for Nuclear research Dubna141980Russia Dubna State University Dubna141982Russia Institute of Nuclear Physics Almaty050032Kazakhstan L.N.Gumilyov Eurasian National University Astana010008Kazakhstan Kazan Federal University Kazan420008Russia Universitéde Strasbourg CNRSStrasbourg67000France IJCLab IN2P3-CNRSUniversitéParis-SaclayOrsay91400France

The complete-fusion reaction^(204)Pb(^(48)Ca,2n)^(250)No was used to study two activities of^(250)No with distinct half-lives.A total of 1357 events were observed in the SFiNx neutron detection *** average number of neutrons emitted per spontaneous fission of^(250)No was determined to be(4.1±0.1).The unusually symmetrical shape of the prompt neutron multiplicity distribution was restored and presented for the first *** tests were performed to compare the prompt neutron multiplicity distributions associated with the ground state and K-isomer state decays.

关键词： spontaneous fission prompt neutrons actinide

Exploring van der Waals materials with high anisotropy:geometrical and optical approaches

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Light(Science & Applications) 2024年第4期13卷 645-653页

作者： Aleksandr S.Slavich Georgy A.Ermolaev Mikhail K.Tatmyshevskiy Adilet N.Toksumakov Olga G.Matveeva Dmitriy v.Grudinin Kirill v.voronin Arslan Mazitov Konstantin v.Kravtsov Alexander v.Syuy Dmitry M.Tsymbarenko Mikhail S.Mironov Sergey M.Novikov Ivan Kruglov Davit A.Ghazaryan Andrey A.vyshnevyy Aleksey v.Arsenin valentyn S.volkov Kostya S.Novoselov Moscow Center for Advanced Studies Kulakova str.20Moscow 123592Russia. Emerging Technologies research Center XPANCEOInternet CityEmmay TowerDubaiUnited Arab Emirates. Donostia International Physics Center(DIPC) Donostia/San-Sebastián 20018Spain. Institute of Materials Ecole Polytechnique Federale de Lausanne1015 LausanneSwitzerland. Department of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia. Laboratory of Advanced Functional Materials Yerevan State UniversityYerevan 0025Armenia. National Graphene Institute(NGI) University of ManchesterManchester M139PLUK. Department of Materials Science and Engineering National University of SingaporeSingapore 03-09 EASingapore. Institute for Functional Intelligent Materials National University of Singapore117544 SingaporeSingapore

The emergence of van der Waals(vdW)materials resulted in the discovery of their high optical,mechanical,and electronic anisotropic properties,immediately enabling countless novel phenomena and *** success inspired an intensive search for the highest possible anisotropic properties among vdW ***,the identification of the most promising among the huge family of vdW materials is a challenging quest requiring innovative ***,we suggest an easy-to-use method for such a survey based on the crystallographic geometrical perspective of vdW materials followed by their optical *** our approach,we found As2S3 as a highly anisotropic vdW *** demonstrates high in-plane optical anisotropy that is~20%larger than for rutile and over two times as large as calcite,high refractive index,and transparency in the visible range,overcoming the century-long record set by *** these benefits,As2S3 opens a pathway towards nextgeneration nanophotonics as demonstrated by an ultrathin true zero-order quarter-wave plate that combines classical and the Fabry–Pérot optical phase ***,our approach provides an effective and easy-to-use method to find vdW materials with the utmost anisotropic properties.

关键词： anisotropy anisotropic high

Translating Difference: reflections on the Interface between Novelistic Discourse and World Literature

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Journal of Foreign Languages and Cultures 2024年第1期8卷 16-30页

作者： E.v.rAMAKrISHNAN Central University of Gujarat

The present essay examines two moments from the evolution of the modern Malayalam novel,in relation to the reception of two classics in world literature,namely victor Hugo's Les Miserables translated into Malayalam between 1925 and 1927 and Garcia Marquez's One Hundred Years of Solitude translated in *** translation of Hugo's novel energized the scene of Malayalam fiction by infusing new modes of representation and widening the intellectual horizons of writers in general,and novelists in *** echoes of Les Miserables could be heard in Malayalam fiction well into the *** struggles against colonial and feudal authorities in Kerala,provided a fertile context for the imaginative interpretation of Hugo's humanist *** paper illustrates this point through close readings of critical essays,autobiographical narratives and debates on the nature of *** fascination of Malayali readers with Garcia Marquez has resulted in the translation of his entire corpus into *** realism as pioneered by Garcia Marquez liberated the Malayalam novelistic narrative from social realist and modernist *** colonial disruption of oral narratives,the consequent cultural amnesia and the struggle to reclaim one's forgotten past are themes that struck a chord in Malayalam writers of *** a detailed discussion of the novel,Moustache by ***,the interface between novelistic discourse and world literature is mapped in the latter part of the essay.

关键词： Malayalam literature translation difference world literature magic realism caste resistance

A novel diurnal and seasonal variation analysis of BTEX in Bengaluru urban area

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research in Cold and Arid regions 2024年第1期16卷 14-19页

作者： H.N.Sowmya M.Dinamani G.P.Shivashankara H.K.ramaraju B.S.Surendra vijaya v.Shanbhag r.Prajwal Department of Civil Engineering Dayananda Sagar College of EngineeringBangalore 560078India Department of Chemistry Dayananda Sagar College of EngineeringBangalore 560078India Department of Physics GFGCVijayanagarBengaluru 560040India

In the urban atmosphere of Bengaluru, various volatile organic compounds(vOCs), particularly Benzene,Toluene, Ethylbenzene, and Xylene(BTEX), have shown an increasing trend in concentration. The present research was conducted during summer and monsoon seasons, focusing on Kadubeesanahalli, a high-traffic area within the Bengaluru Metropolitan City. Hourly sample data was collected using a BTEX analyzer(Model GC955-600) and subsequently transformed into daily, monthly, and seasonal values. The study revealed distinct patterns in benzene concentrations. Benzene levels were lowest during the early morning hours, specifically from 1:00 *** 7:00 a.m.. Concentrations then increased from 7:00 a.m. to 9:00 a.m. and again from 4:00 p.m. to 11:00 p.m.,corresponding to the morning and evening peak traffic hours. However, between 10:00 a.m. and 4:00 p.m., the concentration decreased due to reduced traffic levels. These diurnal variations in benzene concentration are influenced by meteorological parameters. Comparing the two seasons, higher concentrations of Benzene, EthylBenzene, and MP-xylene were observed during the summer season. This increase is attributed to the elevated temperatures during summer, which promote the vaporization of BTEX compounds. Conversely, lower BTEX concentrations were recorded during the monsoon season due to the wet deposition process. The observed positive correlation(r > 0.5) among BTEX parameters strongly suggests a common source, most likely originating from vehicular emissions.

关键词： BTEX Summer variation Meteorological parameters Correlation