检索结果-南通市图书馆

first Detailed Photometric Investigation on the Nature of Contact Binary System AA Cet

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2023年第7期23卷 154-163页

作者： m.f.Yıldırım.f.Soydugan Çanakkale Onsekiz mart University Astrophysics Research Center and Ulupınar Observatory17020ÇanakkaleTurkey Çanakkale Onsekiz mart University Faculty of SciencesDepartment of Physics17020ÇanakkaleTurkey

The TESS light curve(LC)of the marginal contact binary A A Cet was analyzed simultaneously with the radial velocity and the orbital period(OP)change of the system was *** physical parameters of the system were obtained by analyzing the LC of A A Cet with the Wilson-Devinney method,and the absolute parameters of the components were calculated using the results *** the components of AA Cet,the masses and radii were calculated as m_(1)=1.39±0.04 m_⊙,m_(2)=0.48±0.02 m_⊙,and R_(1)=1.64±0.03 R_⊙,R_(2)=1.01±0.04 R_⊙,*** Cet is a marginal contact binary with a temperature difference of 1305 K between its components.A total of 14 eclipse times were obtained from the TESS data and used in the OP analysis together with those collected from the *** has been observed that the change in the OP of AA Cet is in the form of a decreasing *** mass transfer between the components has been interpreted as the reason for this *** OP decrease amount of A A Cet was obtained as dP/dt=0.0062±0.0006 s yr^(-1).and the reason for this decrease was attributed to a 3.3(9)×10^(-8)m_⊙.mass transfer per year from the more massive component to the less massive *** age of A A Cet has been estimated as 7 Gyr,as the age of contact systems helps us to understand their evolution.

关键词： (stars:)binaries:eclipsing stars:fundamental parameters stars:individual(AA Cet)

Dynamics of strong and radiative decays of D_s-mesons in the hadrogenesis conjecture

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics C 2010年第9期34卷 1320-1323页

作者： m.Soyeur m.f.m.Lutz Irfu/SPhN CEA/Saclay GSI Planckstrasse 1

The positive parity scalar D ＊ s0 （2317） and axial-vector D ＊ s1 （2460） charmed strange mesons are generated by coupled-channel dynamics through the s-wave scattering of Goldstone bosons off the pseudoscalar and vector D（D s ）-meson ground *** specific masses of these states are obtained as a consequence of the attraction arising from the Weinberg-Tomozawa interaction in the chiral *** corrections to order Q 2 χ are calculated and found to be *** D ＊ s0 （2317） and D ＊ s1 （2460） mesons decay either strongly into the isospin-violating π 0 D s and π 0 D ？ s channels or *** show that the π 0-η and （K^ 0 D ^＋-K^ ＋ D^ 0 ） mixings act constructively to generate strong widths of the order of 140 keV and emphasize the sensitivity of this value to the KD component of the *** one-loop contribution to the radiative decay amplitudes of scalar and axial-vector states is calculated using the electromagnetic Lagrangian to chiral order Q 2 χ .We show the importance of taking into account processes involving light vector mesons explicitly in the dynamics of electromagnetic *** radiative width are sensitive to both η D s and KD components,hence providing information complementary to the strong widths on the positive parity D s-meson structure.

关键词： charmed mesons D*s0 (2317) D*s1 (2460)

Teleportation of unknown states of a qubit and a single-mode field in strong coupling regime without Bell-state measurement

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2023年第2期75卷 73-79页

作者： f Jahanbakhsh m K Tavassoly Optics and Laser Group Faculty of PhysicsYazd UniversityYazd 89195-741Iran

In this paper,we develop the teleportation scheme in[Zheng in Phys Rev A 69,064302,2004],in the sense that,we work in the strong atom.field coupling regime wherein the rotating wave approximation(RWA)is no longer *** achieve the purpose,a scheme consisting of a qubit interacting with a single-mode quantized field is described via the Rabi model(counter rotation terms are taken into account).Our first aim is to teleport an unknown atomic state of a qubit(which interacts with the quantized field in a cavity)to a second qubit(exists in another distant cavity field),beyond the RWA and without the Bell-state measurement *** the continuation,in a similar way,we teleport an unknown state of a single-mode field *** fact,it is shown that,in this regime,after applying some particular conditions,containing the interaction time of atom.field in the cavities,adjusting the involved frequencies,as well as the atom.field coupling in the model,if a proper measurement is performed on the state of the first qubit(the related field in the cavity),the unknown states of the qubit(field)can be teleported from the first qubit(cavity field)to the second qubit(cavity field),*** show that in both considered cases,the teleportation protocol is successfully performed with the maximum possible fidelity,1,and the acceptable success probability,0.25.

关键词： strong atom.field coupling Rabi model quantum teleportation success probability fidelity

Control and vibration analyses of a sandwich doubly curved micro-composite shell with honeycomb,truss,and corrugated cores based on the fourth-order shear deformation theory

在线全文

学校读者我要写书评

暂无评论

Applied mathematics and mechanics(English Edition) 2024年第10期45卷 1773-1790页

作者： f.SHIRDELAN m.mOHAmmADImEHR f.BARGOZINI Department of Solid mechanics Faculty of Mechanical EngineeringUniversity of KashanKashan 87317-53153Iran

Curved shells are increasingly utilized in applied engineering due to their shared characteristics with other sandwich structures,flexibility,and attractive ***,the inability of controlling and regulating vibrations and destroying them afterward is a challenge to *** this paper,the curve shell equations and a linear quadratic regulator are adopted for the state feedback design to manage the structure vibrations in state space forms.A five-layer sandwich doubly curved micro-composite shell,comprising two piezoelectric layers for the sensor and actuator,is modeled by the fourth-order shear deformation *** core(honeycomb,truss,and corrugated)is analyzed for the bearing of transverse shear *** results show that the honeycomb core has a greater effect on the *** the parameters related to the core and the weight percentage of graphene increase,the frequency *** uniform distribution of graphene platelets results in the lowest natural frequency while the natural frequency ***,without taking into account the piezoelectric layers,the third-order shear deformation theory(TSDT)and fourth-order shear deformation theory(fOSDT)align ***,when the piezoelectric layers are incorporated,these two theories diverge significantly,with the frequencies in the fOSDT being lower than those in the TSDT.

关键词： vibration and control doubly curved shell micro-composite honeycomb truss corrugate core

Interactive data styling and multifocal visualization for a multigrid web-based Digital Earth

在线全文

学校读者我要写书评

暂无评论

International Journal of Digital Earth 2021年第3期14卷 288-310页

作者： m.J.Sherlock m.Hasan f.f.Samavati Department of Computer Science University of CalgaryCalgaryCanada

Globe-based Digital Earth(DE)is a promising system that uses 3D models of the Earth for integration,organization,processing,and visualization of vast multiscale geospatial *** growing size and scale of geospatial datasets present significant obstacles to interactive viewing and meaningful visualizations of these DE *** address these challenges,we present a novel web-based multiresolution DE system using a hierarchical discretization of the globe on both server and client *** presented web-based system makes use of a novel data encoding technique for rendering large multiscale geospatial datasets,with the additional capability of displaying multiple simultaneous *** the data needed for the current views and scales are encoded and *** leverage the power of GPU acceleration on the client-side to perform real-time data rendering and dynamic *** rendering of multiple views allows us to support multilevel focus+context visualization,an effective approach to navigate through large multiscale global *** client–server interaction as well as the data encoding,rendering,styling,and visualization techniques utilized by our presented system contribute toward making DE more accessible and informative.

关键词： Digital Earth Discrete Global Grid System data integration data fusion multilevel focus+context visualization spatial resolution context awareness

Synthesis of 3-(aryl)-2-thioxo-2,3-dihydroquinazolin-4(1H)-one derivatives using heteropolyacids as green,heterogeneous and recyclable catalysts

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2011年第2期22卷 131-134页

作者： S.Allameh m.m.Heravi m.m.Hashemi f.f.Bamoharram Department of Chemistry Science and Research BranchIslamic Azad UniversityTehranIran Department of Chemistry School of SciencesAlzahra UniversityVanakTehranIran Department of Chemistry Faculty of SciencesIslamic Azad UniversityMashhad BranchMashhadIran

Reaction of isatoic anhydride with aniline derivatives gave 2-amino-N-（aryl）*** latters reacted with phenyli-sothiocyanate in the presence of heteropolyacids in various solvents which afforded 3-（aryl）-2-thioxo-2,3-dihydroquinazolin- 4（1H）-one *** effects of various heteropolyacids including Preyssler and Keggin on the yields and reaction times have been investigated.

关键词： Thioxo-quinazolinones Recyclable catalysts Heteropolyacids Heterogeneous

A passive-biped model with multiple routes to chaos

在线全文

学校读者我要写书评

暂无评论

Acta mechanica Sinica 2011年第2期27卷 277-284页

作者： f. farshimi m. Naraghi Department of mechanical Engineering Amirkabir University of Technology Tehran Iran

This paper presents a new passive-biped model consisting of a simplest walking model beneath an upper body, with no kinematic constraint. The upper body is attached to the legs with a linear torsional spring. The model is a passive dynamic walker, so it walks down a slope without energy input. The governing equations of motion are derived and simulated for the parameter analysis purposes. Simulation results reveal some different routes to chaos that have not been observed in previous models.

关键词： Passive-biped Routes to chaos Upper body Bifurcation

modified Burzynski criterion with non-associated flow rule for anisotropic asymmetric metals in plane stress problems

在线全文

学校读者我要写书评

暂无评论

Applied mathematics and mechanics(English Edition) 2015年第3期36卷 303-318页

作者： f.mOAYYEDIAN m.KADKHODAYAN Department of mechanical Engineering Ferdowsi University of Mashhad

The Burzynski criterion is developed for anisotropic asymmetric metals with the non-associated flow rule （NAfR） for plane stress problems. The presented pressure depending on the yield criterion can be calibrated with ten experimental data, i.e., the tensile yield stresses at 0°, 45°, and 90°, the compressive yield stresses at 0°, 15°, 30°, 45°, 75°, and 90° from the rolling direction, and the biaxial tensile yield stress. The corresponding pressure independent plastic potential function can be calibrated with six experimental data, i.e., the tensile R-values at 0°, 15°, 45°, 75°, and 90° from the rolling direction and the tensile biaxial R-value. The downhill simplex method is used to solve these ten and six high nonlinear equations for the yield and plastic potential functions, respectively. The results show that the presented new criterion is appropriate for anisotropic asymmetric metals.

关键词： modified Burzynski criterion pressure dependent asymmetric metal down-hill simplex method non-associated flow rule (NAfR)

Synthesis and Crystal Structure of a New Potassium Yttrium Diphosphate Dihydrate KYP_2O_7·2H_2O

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2008年第10期27卷 1199-1204页

作者： férid m Horchani-Naifer K Unité de Recherches de matériaux de Terres Rares Centre National de Recherches en Sciences des MatériauxB.P.95 Hammam-Lif 2050Tunisie

The dihydrated potassium yttrium diphosphate, KYP2O7·2H2O, has been synthesized for the first time. Single-crystal XRD study has allowed the determination of its structure and correct formula. It crystallizes in the monoclinic system, space group P21/c, with the cell parameters a = 7.7069（3）, b = 10.5801（4）, c = 10.0204（5）A,β = 93.24（3）A, V= 815.76（6）A^3, Z= 4, mr = 337.98, f（000） = 656, Dc = 2.752 g/cm^3 and/t = 8.073 mm^-1. The single-crystal structure was solved from 1856 unique reflections with the final R = 0.0365 and wR = 0.0772, refined with 119 parameters. The atomic arrangement of KYP2O7·2H2O is built by the P2O7 groups, the YO7 and the KO10 polyhedrons which are connected by corner and edge-sharing to form a three-dimensional framework. Water molecules are directly bonded to the Y and K atoms, and they are located in channels running along the a direction.

关键词： crystal structure yttrium diphosphate infrared spectrum TGA-DTA analysis