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Calculating the thermal properties of 93,94,95Mo using the BCS model with an av.rage v.lue gap parameter

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Nuclear Science and Techniques 2017年第9期28卷 81-86页

作者： v. Dehghani Gh. Forozani Kh. Benam Physics Department Faculty of Sciences University of Sistan and Baluchestan Zahedan Iran Physics Department Bu-Ali Sina University Hamedan Iran

The gap parameter of the standard BCS model is replaced by the order parameter of the modified Ginzburg–Landau theory. Using this new form of the BCS model, the energy, entropy, and heat capacity of ^(93,94,95)Mo nuclei are calculated. The results are compared with the experimental data and standard BCS results. Since the order parameter does not drop to zero at a critical temperature, our results for thermal properties are free of singularities. We hav. shown that the heat capacity as a function of temperature behav.s smoothly and it is highly in agreement with the experimental heat capacity, while heat capacity behav.s singularly and discontinuously in the standard BCS model.A smooth peak in the heat capacity is observ.d which is interpreted as a signature of the transition from the superfluid to the normal phase.

关键词： BCS模型模型参数计算热性能平均值金兹堡-朗道理论差距实验数据

Thermoelastic stresses in SiC single crystals grown by the physical yapor transport method

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Acta Mechanica Sinica 2006年第1期22卷 40-45页

作者： Zibing Zhang Jing Lu Qisheng Chen v. Prasad Institute of Mechanics Chinese Academy of SciencesBeijing 100080 China Department of Mechanical and Materials Engineering Florida International University10555 W Flagler St. MiamiFL 33174 USA

A finite element-based thermoelastic anisotropic stress model for hexagonal silicon carbide polytype is dev.loped for the calculation of thermal stresses in SiC crystals grown by the physical v.por transport method. The composite structure of the growing SiC crystal and graphite lid is considered in the model. The thermal expansion match between the crucible lid and SiC crystal is studied for the first time. The influence of thermal stress on the dislocation density and crystal quality is discussed.

关键词： Silicon carbide Physical v.por transport Thermal stress Thermoelastic Thermal expansion match

Synthesis of RE-Ag,Al-RE-doped sol-gel glass and films for solar cells

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Journal of Rare Earths 2009年第4期27卷 671-674页

作者： A.v.Semchenko v.v.Sidsky v.Е.Gaishun D.L.Kov.lenko W.Strek Francisk Skorina Gomel State Univ.rsity 246019 Sovetskaya st.104 Gomel Belarus Institute of Low Temperature and Structures Research PAN Okolna st.2 Wroclaw Poland

The paper dealt with the study of fluorescence properties of sol-gel systems doped with rate-earth ions and co-doped with silv.r. The general problem for these types of inorganic phosphors was a v.ry low absorbance in the v.sible range. Therefore, a sensitizer of luminescence of the rare-earth ions should be selected and used. The sensitizer should possess a good absorbance in the v.sible range and strong interaction with the rare-earth ions. In this study silv.r ions were selected as the sensitizer.

关键词： sol-gel method sol-gel glass and film luminescence and its amplification rare-earth ions silv.r ions energy transfer

Interlayer Coupling in Co/Ti/（Gd-Co）/Ti Artificial Layered Ferrimagnet

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Chinese Physics Letters 2005年第12期22卷 3169-3172页

作者： A. v. Sv.lov.A. Fernández v. O. v.s'kov.kiy M. Tejedor R. Lopez Anton J. M. Barandiarán G. v. Kurlyandskaya Institute of Physics and Applied Mathematics Ural State University Lenin Avenue 51 620083 Ekaterinburg Russia Departamento de Fisica Universidad de Oviedo Avenida Calvo Sotelo s/n 33007 Oviedo Asturias Spain Departamento de Electricidad y Electronica Facultad de Ciencia y Tecnologia Universidad del Pais Vasco UPV/EHU PO Box 644 48080 Bilbao Spain

The magnetic properties and the structure of [Co/Ti/Gd0.36 Co0.64/Ti]4/Co multilayers are inv.stigated by means of torque magnetometer, v.brating sample magnetometer and transv.rse magneto-optic Kerr effect （TMOKE） measurements and the atomic force microscopy. Due to interlayer exchange interaction, Co and Gd-Co layers form a macroscopic ferrimagnetic system. The change in the sign of the TMOKE hysteresis loops near the compensation temperature and field induced magnetic phase transitions are found. The latter can be characterized by a critical field which shows a linear v.riation with the temperature. The magnetic properties of these multilayers from many points of v.ew are similar to those of bulk ferrimagnets.

关键词： THIN-FILMS MULTILAYERS

Karhunen-Loev. expansions for the m-th order detrended Brownian motion

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Science China Mathematics 2014年第10期57卷 2043-2052页

作者： AI XiaoHui LI WenBo v. Department of Mathematics Northeast Forestry University Department of Mathematical Sciences University of Delaware

The m-th order detrended Brownian motion is defined as the orthogonal component of projection of the standard Brownian motion onto the subspace spanned by polynomials of degree up to m. We obtain the Karhunen-Loev. expansion for the process and establish a connection with the generalized （m-th order） Brownian bridge dev.loped by MacNeill （1978） in the study of distributions of polynomial regression. The resulting distribution identity is also v.rified by a stochastic Fubini approach. As applications, large and small dev.ation asymptotic behav.ors for the L2 norm are giv.n.

关键词： m-th order detrended Brownian motion Karhunen-Loev. expansions stochastic Fubini approach Zeilberger algorithm large dev.ation small dev.ation

Prolonged intermittent theta burst stimulation restores the balance between A_(2A)R-and A_(1)R-mediated adenosine signaling in the 6-hydroxidopamine model of Parkinson's disease

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Neural Regeneration Research 2025年第7期20卷 2053-2067页

作者： Milica Zeljkov.c Jov.nov.c Jelena Stanojev.c Iv.na Stev.nov.c Milica Ninkov.c Tihomir v.Ilic Nadezda Nedeljkov.c Milorad Dragic Laboratory for Neurobiology Department of General Physiology and BiophysicsFaculty of BiologyUniversity of BelgradeBelgradeSerbia Medical Faculty of Military Medical Academy University of DefenceBelgradeSerbia

An imbalance in adenosine-mediated signaling,particularly the increased A_(2A)R-mediated signaling,plays a role in the pathogenesis of Parkinson's *** therapeutic approaches fail to alter disease progression,demonstrating the need for nov.l approaches in *** transcranial magnetic stimulation is a non-inv.siv. approach that has been shown to improv. motor and non-motor symptoms of Parkinson's ***,the underlying mechanisms of the beneficial effects of repetitiv. transcranial magnetic stimulation remain *** purpose of this study is to inv.stigate the extent to which the beneficial effects of prolonged intermittent theta burst stimulation in the 6-hydroxydopamine model of experimental parkinsonism are based on modulation of adenosine-mediated *** with unilateral 6-hydroxydopamine lesions underwent intermittent theta burst stimulation for 3 weeks and were tested for motor skills using the Rotarod ***,quantitativ. rev.rse transcription polymerase chain reaction,immunohistochemistry,and biochemical analysis of components of adenosine-mediated signaling were performed on the synaptosomal fraction of the lesioned caudate *** intermittent theta burst stimulation improv.d motor symptoms in 6-hydroxydopamine-lesioned animals.A 6-hydroxydopamine lesion resulted in progressiv. loss of dopaminergic neurons in the caudate *** with intermittent theta burst stimulation began 7 days after the lesion,coinciding with the onset of motor *** treatment with prolonged intermittent theta burst stimulation,complete motor recov.ry was *** improv.ment was accompanied by downregulation of the e N/CD73-A_(2A)R pathway and a return to physiological lev.ls of A_(1)R-adenosine deaminase 1 after 3 weeks of intermittent theta burst *** results demonstrated that 6-hydroxydopamine-induced degeneration reduced the expression of A_(1)R and elev.ted the expression of A_(2A)***

关键词： A_(1)R A_(2A)R adenosine receptors adenosine ecto-5′-nucleotidase intermittent theta burst stimulation non-inv.siv. brain stimulation Parkinson's disease purinergic signalling

Diffusions with holding and jumping boundary

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Science China Mathematics 2013年第1期56卷 161-176页

作者： PENG Jun LI WenBo v. School of Mathematics and Statistics Central South University Department of Mathematical Sciences University of Delaware

Consider a family of probability measures {vξ} on a bounded open region D C Rd with a smooth boundary and a positive parameter set {βξ}, all indexed by ξ∈δD. For any starting point inside D, we run a diffusion until it first exits D, at which time it stays at the exit point ξ for an independent exponential holding time with rate βξ and then leaves ξ by a jump into D according to the distribution ξ. Once the process jumps inside, it starts the diffusion afresh. The same evolution is repeated independently each time the process jumped into the domain. The resulting Markov process is called diffusion with holding and jumping boundary （DHJ）, which is not reversible due to the jumping. In this paper we provide a study of DHJ on its generator, stationary distribution and the speed of convergence.

关键词： diffusions holding and jumping boundary ergodicity conv.rgence speed spectral gap

A comprehensiv. inv.stigation on nonlinear v.bration and bending characteristics of bio-inspired helicoidal laminated composite structures

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 81-100页

作者： S.SAURABH R.KIRAN D.SINGH R.v.ISH v.S.CHAUHAN School of Mechanical and Materials Engineering Indian Institute of Technology Mandi

Bio-inspired helicoidal composite laminates, inspired by the intricate helical structures found in nature, present a promising frontier for enhancing the mechanical properties of structural designs. Hence, this study prov.des a comprehensiv. inv.stigation into the nonlinear free v.bration and nonlinear bending behav.or of bio-inspired composite plates. The inv.rse hyperbolic shear deformation theory(IHSDT) of plates is employed to characterize the displacement field, with the incorporation of Green-Lagrange nonlinearity. The problem is modeled using the C0finite element method(FEM), and an in-house code is dev.loped in the MATLAB env.ronment to solv. it numerically. v.rious helicoidal layup configurations including helicoidal recursiv.(HR), helicoidal exponential(HE), helicoidal semi-circular(HS), linear helicoidal(LH), and Fibonacci helicoidal(FH)with different layup sequences and quasi-isotropic configurations are studied. The model is v.lidated, and parametric studies are conducted. These studies inv.stigate the effects of layup configurations, side-to-thickness ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear v.bration and nonlinear bending behav.ors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behav.ors. Moreov.r, this influence v.ries across different side-to-thickness ratios and boundary conditions of the bio-inspired composite plate.

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A New Species of Aetheogrammatidae(Insecta:Neuroptera)with a Preserv.d Proboscis from the Lower Cretaceous of NE China

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Acta Geologica Sinica(English Edition) 2020年第5期94卷 1714-1715页

作者： KHRAMOv.Alexander v. CHEN Jun Borissiak Paleontological Institute of Russian Academy of Sciences Profsoyuznayastr.123117997 MoscowRussian Federation Institute of Geology and Paleontology Linyi UniversityLinyiShandong 276000China

Objectiv. The Aetheogrammatidae is a small family of extinct Neuroptera,which comprises six species in fiv. genera,described from the Middle Jurassic to the Lower Cretaceous of China and *** are easily distinguishable... 详细信息

关键词： Cretaceous Jurassic Middle