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The nonrelativistic oscillator strength of a hyperbolic-type potential

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Chinese Physics B 2013年第6期22卷 105-109页

作者： h.hassanabadi S.Zarrinkamar B.h.Yazarloo Department of Basic Sciences Shahrood BranchIslamic Azad UniversityShahroodIran Department of Basic Sciences Garmsar BranchIslamic Azad UniversityGarmsarIran

We consider the D-dimensional SchrSdinger equation under the hyperbolic potential V0（1 -coth（ar））＋ 171 （1 - coth（ar））2. Using a Pekeris-type approximation, the approximate analytical solutions of the problem are obtained via the supersymmetric quantum mechanics. The behaviors of energy eigenvalues versus dimension are discussed for various quantum numbers. Useful expectation values as well as the oscillator strength are obtained.

关键词： Schroedinger equation D-dimensional space hyperbolic potential supersymmetry quantum me-chanics oscillator strength

Epitaxial growth of Ge_(1-x)Sn_x films with x up to 0.14 grown on Ge(00l) at low temperature

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Chinese Physics B 2014年第8期23卷 591-594页

作者：陶平黄磊 Cheng h h 王焕华吴小山 Laboratory of Solid State Microstructures Nanjing University National Taiwan University Center for Condensed Matter Sciences Beijing Synchrotron Radiation Facility (BSRF) Institute of High Energy Physics

We characterize the structures of Ge1-xSnx films with x up to 0.14 grown on Ge （001） by molecular-beam epitaxy at low temperature. The results show that Ge1-xSnx films are fully strained even at high Sn composition. The in-plane lattice parameters remain exactly the same as that of the substrate. Depth sensitivity analysis of the lattice parameters indicates that the strains of the epitaxial films are all in homogeneity. The films are fully strained. Poisson ratios, the force constants for the bonds between Ge and Sn are estimated and discussed in the present paper. Raman results show Ge-Ge, Ge-Sn, Sn-Sn vibrational modes. The Sn-Sn bond aggregation may respond to the high quality of our films. The fully strained epitaxy films with high content of Sn may be useful in designing the high quality GeSn films.

关键词： GeSn films high resolution X-ray diffraction fully-strained Raman measurements

Cranial variation in allactagine jerboas(Allactaginae,Dipodidae, Rodentia): a geometric morphometric study

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Zoological Research 2021年第2期42卷 182-194页

作者： Bader h.Alhajeri Department of Biological Sciences Kuwait UniversitySafat 13060Kuwait

Allactaginae is a subfamily of dipodids consisting of four-and five-toed jerboas(Allactaga, Allactodipus,Orientallactaga, Pygeretmus, Scarturus) found in open habitats of Asia and North Africa. Recent molecular phylogenies have upended our understanding of this group's systematics across taxonomic scales. here, I used cranial geometric morphometrics to examine variation across 219 specimens of 14 allactagine species(Allactaga major, A. severtzovi, Orientallactaga balikunica, ***, O. sibirica, Pygeretmus platyurus, P. pumilio,P. shitkovi, Scarturus aralychensis, S. euphraticus,S. hotsoni, S. indicus, S. tetradactylus, S. williamsi)in light of their revised taxonomy. Results showed no significant sexual size or shape dimorphism. Species significantly differed in cranial size and shape both overall and as species pairs. Species identity had a strong effect on both cranial size and shape. Only a small part of cranial shape variation was allometric,with no evidence of unique species allometries, and most specimens fit closely to the common allometric regression vector. Allactaga was the largest,followed by Orientallactaga, Scarturus, and finally Pygeretmus. Principal component 1(PC1) separated O. bullata+O. balikunica+S. hotsoni(with inflated bullae along with reduced zygomatic arches and rostra) from A. major+A. severtzovi+O. sibirica(with converse patterns), while PC2 differentiated Orientallactaga(with enlarged cranial bases and rostra along with reduced zygomatic arches and foramina magna) from Scarturus+Pygeretmus(with the opposite patterns). Clustering based on the unweighted pair group method with arithmetic mean(UPGMA) contained the four genera, but S. hotsoni clustered with O. bullata+O. balikunica and *** clustered with A. major+A. severtzovi, likely due to convergence and allometry, respectively.

关键词： Allactaga Cranial morphometrics Five-toed jerboas Orientallactaga Pygeretmus Scarturus

Proton-neutron symplectic model description of ^(20)Ne

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Chinese Physics C 2022年第4期46卷 141-149页

作者： h.G.Ganev Joint Institute for Nuclear Research DubnaRussia

A microscopic description of the low-lying positive-parity rotational bands in ^(20)Ne is given within the framework of the symplectic-based proton-neutron shell-model approach provided by the proton-neutron symplectic model(PNSM).For this purpose,a model hamiltonian is *** includes an algebraic interaction lying in the enveloping algebra of the Sp(12,R)dynamical group of the PNSM,which introduces both horizontal and vertical mixings of different SU(3)irreducible representations within the Sp(12,R)irreducible collective space of ^(20)Ne.A good overall description is obtained for the excitation energies of the ground and first two excited β bands,including the ground state intraband B(E2)quadrupole collectivity and the known interband B(E2)transition probabilities between the low-lying collective states,without utilizing an effective charge.

关键词： proton-neutron symplectic model shell-model states collective states in^(20)Ne

Marinoan glaciation in the Indian subcontinent——Anatomy and global implications

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Journal of Palaeogeography 2024年第2期13卷 293-308页

作者： h.N.Bhattacharya Department of Earth Sciences Techno India UniversityWest BengalSector VSalt LakeKolkata700091India

Detailed sedimentological analysis of the Pokaran Boulder Bed,representing the most basal unit of the Neoproterozoic-Lower Cambrian Marwar Supergroup,clearly indicates its glacial *** glacial sediments are interpreted as an ice-contact submarine fan *** on the detrital and inherited zircon population of the Marwar Supergroup sediments and interlayered pyroclastic deposits,a Marinoan cryochron of the Cryogenian Period is envisaged for the Pokaran Boulder *** well-preserved Ediacaran elements in the post-glacial sedimentary succession also support a Cryogenian to Early Cambrian age of the Marwar *** glacial deposition at the base of the Marwar Supergroup strengthens the regional correlation between the studied sediments with the Lesser himalayan Blaini-Krol-Tal sediments and the haqf Supergroup of *** available zircon ages and paleomagnetic data of the Malani Igneous suite,along with the Marinoan glacial deposits,detrital zircon ages,and Ediacaran fossil elements of the Marwar Supergroup add significant information to the Neoproterozoic Earth history.

关键词： Neoproterozoic Marinoan glaciation Diamictites Pokaran Boulder Bed Marwar Supergroup

Particle Paths of Lagrangian Velocity Distribution Simulating the Spiral Arms of Galaxy M51

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Journal of Thermal Science 2008年第1期17卷 61-63页

作者： Georgios h.Vatistas Department of Mechanical and Industrial Engineering Concordia UniversityMontrealQuebecCanada H3G 1M8

Galaxies are huge families of stars held together by their own gravities. The system M51 is a spiral galaxy. It possesses billions of stars. The range of the spiral arms extends hundred thousand light years. The present study is in an attempt in using the particle paths of the Lagrangian flow field to simulate the spiral arms of Galaxy M51. The Lagrangian flow field is introduced. The initial locations of fluid particles in the space between two concen- tric cylinders are ftrst specified. Then a linear velocity distribution of the fluid particles is used with different an- gle rotations of the particles to obtain the particle paths in the Lagrangian diagram. For simulating the spiral arms of Galaxy M51, the Lagrangian M51 diagram is developed. The particle paths of the Lagrangian M51 diagram agree quite well with the spiral arms of Galaxy M51.

关键词： Lagrangian flow field Particle path Dimensionless normalization Spiral arms Galaxy M51

Matrix elements in the SU(1,1)⊗SO(6)limit of the proton-neutron symplectic model

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Chinese Physics C 2021年第11期45卷 101-114页

作者： h.G.Ganev Joint Institute for Nuclear Research DubnaRussia

The matrix elements along the reduction chain Sp(12,R)⊃SU(1,1)⊗SO(6)⊃U(1)⊗SUpn(3)⊗SO(2)⊃SO(3)of the proton-neutron symplectic model(PNSM)are *** analytical expressions are obtained for the matrix elements of the basic building blocks of the PNSM and the Sp(12,R)symplectic generators,allowing the computation of matrix elements of other physical operators as *** computational technique developed in the present study generally provides us with the required algebraic tool for performing realistic symplectic-based shell-model calculations of nuclear collective *** two simple examples,we illustrate the application of the theory.

关键词： matrix elements proton-neutron symplectic model SU(1 1)⊗SO(6)limit Sp(12 R)dynamical algebra

Microscopic shell-model description of irrotational-flow dynamics in^(102)Pd

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Chinese Physics C 2024年第1期48卷 82-93页

作者： h.G.Ganev Joint Institute for Nuclear Research DubnaRussia Institute of Mechanics Bulgarian Academy of SciencesSofiaBulgaria

The structure of the low-lying collective excitations in 102Pd is examined within the recently proposed microscopic shell-model version of the Bohr-Mottelson(BM)collective model.A good description of the excitation energies of the lowest ground,γ,andβbands,as well as the staggering function between the collective states of theγband and some other energy-dependent quantities,is *** low-energy intraband and interband quadrupole dynamics is reasonably well described within the present proton-neutron sympletic based shell-model approach without the use of an effective charge and compared with the predictions of nuclear structure *** obtained results of the present study shed light on the question of the existence of irrotational-flow type quadrupole dynamics,which lies on the ground of the original BM model of quantized vibrations and surface-wave rotations in atomic nuclei.

关键词： shell-model version of the Bohr-Mottelson model irrotational-flow dynamics proton-neutron symplectic model Sp(12,R)dynamical algebra

Self-phase modulation via similariton solutions of the perturbed NLSE Modulation instability and induced self-steepening

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Communications in Theoretical Physics 2022年第8期74卷 41-50页

作者： h I Abdel-Gawad Department of Mathematics Faculty of Science Cairo University Egypt

The perturbed nonlinear Schrodinger equation(PNLSE)describes the pulse propagation in optical fibers,which results from the interaction of the higher-order dispersion effect,self-steepening(SS)and self-phase modulation(SPM).The challenge between these aforementioned phenomena may lead to a dominant one among *** is worth noticing that the study of modulation instability(MI)leads to the inspection of dominant phenomena(DPh).Indeed,the MI triggers when the coefficient of DPh exceeds a critical value and it may occur that the interaction leads to wave *** PNLSE is currently studied in the literature,mainly on finding traveling wave ***,we are concerned with analyzing the similarity solutions of the *** exact solutions are obtained via introducing similarity transformations and by using the extended unified *** solutions are evaluated numerically and they are shown *** is observed that the intensity of the pulses exhibits self steepening which progresses to shock soliton in ultrashort time(or near t=0).Also,it is found that the real part of the solution exhibits self-phase modulation in *** study of(MI)determines the critical value for the coefficients of SS,SPM,or high dispersivity to occur.

关键词： Perturbed NLSE steepening self–phase modulation extended unified method