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Chinese Physics B 2016年第10期25卷 45-51页

作者： r Pakniat M K Tavassoly M h Zandi Faculty of Physics Shahid Bahonar University of Kerman Faculty of Physics Atomic and Molecular Group Yazd University research Group of Optics and Photonics Yazd University

We outline a scheme for entanglement swapping based on cavity QED as well as quasi-Bell state measurement(quasiBSM) methods. The atom–field interaction in the cavity QED method is performed in small and large detuning *** assume two atoms are initially entangled together and, distinctly two cavities are prepared in an entangled coherent–coherent state. In this scheme, we want to transform entanglement to the atom-field system. It is observed that, the fidelities of the swapped entangled state in the quasi-BSM method can be compatible with those obtained in the small and large detuning regimes in the cavity QED method(the condition of this compatibility will be discussed). In addition, in the large detuning regime, the swapped entangled state is obtained by detecting and quasi-BSM approaches. In the continuation,by making use of the atom–field entangled state obtained in both approaches in a large detuning regime, we show that the atomic as well as field states teleportation with complete fidelity can be achieved.

关键词： entanglement swapping quantum teleportation cavity QED quasi-Bell state measurement

Analytical solution approach for nonlinear buckling and postbuckling analysis of cylindrical nanoshells based on surface elasticity theory

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Applied Mathematics and Mechanics(English Edition) 2016年第7期37卷 903-918页

作者： r.ANSArI T.POUrAShrAF r.GhOLAMI h.rOUhI Department of Mechanical Engineering University of Guilan Department of Mechanical Engineering Lahijan BranchIslamic Azad University Department of Engineering Science Faculty of Technology and Engineering East of GuilanUniversity of Guilan

The size-dependent nonlinear buckling and postbuckling characteristics of circular cylindrical nanoshells subjected to the axial compressive load are investigated with an analytical approach. The surface energy effects are taken into account according to the surface elasticity theory of Gurtin and Murdoch. The developed geometrically nonlinear shell model is based on the classical Donnell shell theory and the von Karman＇s hypothesis. With the numerical results, the effect of the surface stress on the nonlinear buckling and postbuckling behaviors of nanoshells made of Si and Al is studied. Moreover, the influence of the surface residual tension and the radius-to-thickness ratio is illustrated. The results indicate that the surface stress has an important effect on prebuckling and postbuekling characteristics of nanoshells with small sizes.

关键词： cylindrical nanoshell surface stress nonlinear buckling postbuckling analytical method

Effect of floor level slit exhaust ventilation system on distribution of house dust

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Journal of Central South University 2012年第3期19卷 696-702页

作者：吕阳 h.Yoshino r.Takaki r.Kurihara A.Mochida h.Yonekura School of Civil Engineering Faculty of Infrastructure EngineeringDalian University of Technology Department of Architecture&Building Science Tohoku University

Based on the fact that the house dust usually falls on the ground, the floor level slit exhaust ventilation system including inlet located at the ceiling and outlet of slit exhaust installed at comer between wall and floor was considered. Experiments and simulations were performed to investigate the flow and diffusion fields that are affected by this floor level slit exhaust ventilation system. The characteristics of airflow with experiments and computation fluid dynamics （CFD） are generally similar except airflow at the location of impinging flow and the location right below the inlet. riboflavin particles were used as the house dust. For the spatial distribution of riboflavin particles in the ventilation system before operation, due to the influence of gravity, different sizes of particles show smooth decay curve. After floor level slit exhaust ventilation system is operated, the decay rate of the particles becomes faster than that after the ventilation system is powered on, and the particles with diameter of 0.5-3.0 μm in the experimental data and calculated values show good agreement.

关键词： house dust floor level slit exhaust riboflavin particles computational fluid dynamics

Dynamic recrystallization Behavior of 13%Cr Martensitic Stainless Steel under hot Working Condition

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Journal of Materials Science & Technology 2012年第5期28卷 467-473页

作者： G.r.Ebrahimi h.Keshmiri A.r.Maldar A.Momeni Metallurgical and Materials Engineering Department Ferdowsi University of MashhadMashhad ***Iran Department of Materials Engineering Sabzevar Tarbiat Moallem UniversitySabzevar ***Iran Materials Science and Engineering Department Hamedan University of TechnologyHamedan ***Iran

In this study,the effect of hot deformation on martensitic stainless steel was carried out in temperatures between 950 to 1100℃ and strain rates of 0.001,0.01 and 0.1 s *** important dynamic recrystallization parameters,the critical strain and the point of maximum dynamic softening,were derived from strain hardening rate vs stress *** the calculated parameters were used to predict the dynamic recrystallized *** results show that critical stress and strain increase with decreasing deformation temperature and increasing strain *** hot deformation activation energy of the steel is also investigated in the present work with 413 kJ/*** experimental flow curves are in fair agreement with the kinetics of dynamic recrystallization model.

关键词： hot deformation Dynamic recrystallization Critical strain

Advances in human stem cell therapies:pre-clinical studies and the outlook for central nervous system regeneration

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Neural regeneration research 2021年第4期16卷 614-617页

作者： Lindsey h.Forbes Melissa r.Andrews Medical research Council Centre for reproductive health The Queen’s Medical Research InstituteUniversity of EdinburghEdinburghUK School of Biological Sciences University of SouthamptonSouthamptonUK

Cell transplantation has come to the forefront of regenerative medicine alongside the discovery and application of stem cells in both research and clinical *** are several types of stem cells currently being used for pre-clinical regenerative therapies,each with unique characteristics,benefits and *** brief review will focus on recent basic science advancements made with embryonic stem cells and induced pluripotent stem *** embryonic stem cells and induced pluripotent stem cells provide platforms for new neurons to replace dead and/or dying cells following *** to their capacity for reprogramming and differentiation into any neuronal type,research in preclinical rodent models has shown that embryonic stem cells and induced pluripotent stem cells can integrate,survive and form connections in the nervous system similar to de novo *** forward however,there are some limitations to consider with the use of either stem cell ***,embryonic stem cells are not an ideal source of cells,genetically,induced pluripotent stem cells are not ideal in terms of personalized treatment for those with certain genetic diseases the latter of which may guide regenerative medicine away from personalized stem cell based therapies and into optimized stem cell ***,the potential of these stem cells in central nervous system regenerative therapy is only beginning to be *** example,through genetic modification,stem cells serve as ideal platforms to reintroduce missing or downregulated molecules into the nervous system to further induce regenerative *** this review,we highlight the limitations of stem cell based therapies whilst discussing some of the means of overcoming these limitations.

关键词： cell transplantation central nervous system regeneration embryonic stem cells induced pluripotent stem cells spinal cord injury

Astrophysical S-factor of the ^(12)C(α, γ)^(16)O reaction at solar energies

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Chinese Physics C 2014年第8期38卷 18-22页

作者： h.Sadeghi r.Ghasemi h.Khalili Department of Physics Faculty of Science Arak University

The astrophysical S-factor of the 4he＋12C radiative capture is calculated in the potential model at the energy range 0.1-2.0 MeV. radiative capture 12C（α,γ） 16O is extremely relevant for the fate of massive stars and determines if the remnant of a supernova explosion becomes a black hole or a neutron star. Because this reaction occurs at low energies, the experimental measurements are very difficult and perhaps impossible. In this paper, radiative capture of the 12C（α,γ） 16O reaction at very low energies is taken as a case study. In comparison with other theoretical methods and available experimental data, good agreement is achieved for the astrophysical S-factor of this process.

关键词： radiative capture the astrophysical S-factor potential model

MODIFICATION OF SODIUM SALT OF PArTIALLY CArBOXYMEThYLATED TAMArIND KErNEL POWDEr ThrOUGh GrAFTING WITh ACrYLONITrILE: SYNThESIS, ChArACTErIZATION AND SWELLING BEhAVIOr

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Chinese Journal of Polymer Science 2013年第12期31卷 1670-1684页

作者： J.h.Trivedi J.r.Jivani K.h.Patel h.C.Trivedi P.G.Dept.of Chemistry Sardar Patel UniversityVallabh Vidyanagar Amneal Phamaceuticals

A graft copolymer of polyacrylonitrile （PAN） with sodium salt of partially carboxymethylated tamarind kernel powder （Na-PCMTKP, DS ^-= 0.15） was synthesized by using ceric ammonium nitrate （CAN） as a redox initiator in an aqueous medium. The optimum reaction conditions for affording maximum percentage of grafting were established by successively varying reaction conditions such as concentrations of nitric acid, CAN, monomer （AN） as well as reaction time, temperature and amount of substrate. The influence of these reaction conditions on the grafting yields was discussed. The kinetic scheme of free radical graft copolymerization was proposed and the experimental results were found to agree very well with the proposed kinetic scheme. The graft copolymer （Na-PCMTKP-g-PAN, percentage of grafting G = 413.76% and percentage of grafting efficiency GE = 96.48%） sample synthesized under the established optimized reaction conditions was hydrolyzed by 0.7 mol-L l NaOh solution at 90-95 ℃ to yield the superabsorbent hydrogel, h-Na-PCMTKP-g-PAN. The swelling behavior of the hydrogel was studied by carrying out its absorbency measurements in low conductivity water, 0.15 mol·L^-1 salt （NaCl, CaCl2 and AlCl3） solutions and simulated urine （SU） solution at different timings. FTIr, TGA and SEM techniques were used to characterize the products.

关键词： Sodium salt of partially carboxymethylated tamarind kernel powder Acrylonitrile Graft copolymerization Superabsorbent hydrogels Swelling behavior.

植物系统发生海报——以演化视角介绍植物多样性的科教资料项目

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生物多样性 2025年

作者：蒋陈焜郁文彬饶广远黎怀成 Julien B.Bachelier hartmut h.hilger Theodor C.h.Cole 北京大学生命科学学院蛋白质与植物基因研究国家重点实验室北京大学前沿交叉学科研究院北京大学-清华大学生命科学联合中心中国科学院西双版纳热带植物园综合保护中心/云南省热带雨林与亚洲象保护重点实验室 Dahlem Centre of Plant Sciences (DCPS)， Institute of Biology， Structural and Functional Plant Diversity， Freie Universit?t Berlin

中国的植物多样性保护行动虽然提升了公众对多样性的认识，但这些努力往往未能深入到理解植物多样性演化及其保护的深层意义。从演化的视角进行植物多样性宣传教育，有利于促进对多样性的综合理解，增进对多样性保护的认可。然而， ... 详细信息

中国的植物多样性保护行动虽然提升了公众对多样性的认识，但这些努力往往未能深入到理解植物多样性演化及其保护的深层意义。从演化的视角进行植物多样性宣传教育，有利于促进对多样性的综合理解，增进对多样性保护的认可。然而，现有资料多集中于物种的识别、鉴定与分类，缺乏从生物演化角度对植物多样性进行系统性介绍的内容。本文介绍了一个具有全球影响力的科教资料案例——由美裔德国植物学家Theodor C. h. Cole发起的植物系统发生海报(Plant Phylogeny Posters)项目。该项目通过整合最新的系统与演化植物学研究成果，以系统发生为线索介绍植物多样性及其亲缘关系，旨在利用系统发生树所蕴含的丰富演化思想内涵，启发读者理解植物多样性与演化。海报以系统发生树结合植物类群的形态、地理分布、物种数量等数据信息，直观展示了多个分类等级的重要类群的演化历史。在数十所大学和科研机构的45位研究人员的努力下， 70张系统发生海报已被翻译成中文，并向所有人免费开放获取。这一科教项目有望为增进公众深入理解植物多样性及其保护行动提供宝贵的资源和帮助。

关键词：植物多样性演化系统发生科教资料

Strain Effect on the Absorption Threshold Energy of Silicon Circular Nanowires

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Communications in Theoretical Physics 2016年第1期65卷 87-91页

作者： r.Khordad h.Bahramiyan Department of Physics College of SciencesYasouj University

In this work,the influence of strain on threshold energy of absorption in Silicon circular nanowires is *** this purpose,we first have used the density functional theory(DFT) to calculate the electron and hole effective ***,we have obtained absorption threshold energy with two different procedures,DFT and effective mass approximation(EMA).We have also obtained the band structures of Si nanowires both DFT and *** results show that:i) the expansive strain increases the hole effective mass while compressive strain increases the electron effective mass,ii) the electron and hole effective masses reduce with decreasing the wire size,iii) the absorption threshold energy decreases by increasing strain for compressive and tensile strain and its behavior as a function of strain is approximately parabolic,iv) the absorption threshold energy(for all sizes) obtained using EMA is greater than the DFT results.

关键词： quantum wire ab initio calculations optical properties mechanical properties

A Squared-Chebyshev wavelet thresholding based 1D signal compression

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Defence Technology（防务技术） 2019年第3期15卷 426-431页

作者： hanan A.r. Akkar Wael A.h. hadi Ibraheem h. Al-Dosari Electronic Engineering in University of Technology Iraq Communication Engineering in University of Technology Iraq Electronic Engineering at Al-rafidain University College Iraq

In this paper a square wavelet thresholding method is proposed and evaluated as compared to the other classical wavelet thresholding methods (like soft and hard). The main advantage of this work is to design and implement a new wavelet thresholding method and evaluate it against other classical wavelet thresholding methods and hence search for the optimal wavelet mother function among the wide families with a suitable level of decomposition and followed by a novel thresholding method among the existing methods. This optimized method will be used to shrink the wavelet coefficients and yield an adequate compressed pressure signal prior to transmit it. While a comparison evaluation analysis is established, A new proposed procedure is used to compress a synthetic signal and obtain the optimal results through minimization the signal memory size and its transmission bandwidth. There are different performance indices to establish the comparison and evaluation process for signal compression;but the most well-known measuring scores are: NMSE, ESNr, and PDr. The obtained results showed the dominant of the square wavelet thresholding method against other methods using different measuring scores and hence the conclusion by the way for adopting this proposed novel wavelet thresholding method for 1D signal compression in future researches.

关键词： PDr (percentage root mean squared difference) rMSE (root mean square error) Signal compression Square wavelet thresholding