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Analysis of interlaminar stress and nonlinear dynamic response for composite laminated plates with interfacial damage

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Acta mechanica Sinica 2008年第6期24卷 709-720页

作者： F.h.Zhu .m.Fu College of mechanics and Aerospace Hunan University410082 ChangshaChina

By considering the effect of interfacial damage and using the variation principle, three-dimensional nonlinear dynamic governing equations of the laminated plates with interfacial damage are derived based on the general sixdegrees-of-freedom plate theory towards the accurate stress analysis. The solutions of interlaminar stress and nonlinear dynamic response for a simply supported laminated plate with interfacial damage are obtained by using the finite difference method, and the results are validated by comparison with the solution of nonlinear finite element method. In numerical calculations, the effects of interfacial damage on the stress in the interface and the nonlinear dynamic response of laminated plates are discussed.

关键词： Laminated plates Geometric nonlinearity Accurate stress analysis Interfacial damage Interlaminar stress Nonlinear dynamic response

Widely tunable linear-cavity multiwavelength fiber laser with distributed Brillouin scattering

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Chinese Optics Letters 2011年第3期9卷 51-53页

作者： m.Ajiya m.h.Al-mansoori m.A.m.hdi Department of Electrical Engineering Faculty of TechnologyBayero University Faculty of Engineering Sohar University Wireless and Photonics Networks Research Center Faculty of EngineeringUniversiti Putra Malaysia

We demonstrate a multiple wavelength Brillouin/erbium fiber laser in a linear cavity *** laser cavity is made up of a fiber loop mirror on one end of the resonator and a virtual mirror generated from the distributed stimulated Brillouin scattering effect on the other *** to the weak reflectivity provided by the virtual mirror,self-lasing cavity modes are completely suppressed from the laser *** Brillouin pump and 1480-nm pump powers of 2 and 130 mW,respectively,11 channels of the demonstrated laser with an average total power of 7.13 dBm can freely be tuned over a span of 37-nm wavelength from 1530 to 1567 nm.

关键词： EDFA Widely tunable linear-cavity multiwavelength fiber laser with distributed Brillouin scattering dBm nm OSNR DCF SBS

An ab initio investigation of vibrational, thermodynamic, and optical properties of Sc_2AlC mAX compound

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Chinese Physics B 2016年第10期25卷 103-108页

作者： m A Ali m T Nasir m R Khatun A K m A Islam S h Naqib Department of Physics Chittagong University of Engineering and Technology Department of Arts & Sciences Bangladesh Army University of Science and Technology Department of Physics University of Rajshahi International Islamic University Chittagong

The structural vibrational, thermodynamical, and optical properties of potentially technologically important, weakly coupled mAX compound, Sc2 Al C are calculated using density functional theory(DFT). The structural properties of ScAlC are compared with the results reported earlier. The vibrational, thermodynamical, and optical properties are theoretically estimated for the first time. The phonon dispersion curve is calculated and the dynamical stability of this compound is investigated. The optical and acoustic modes are observed clearly. We calculate the helmholtz free energy(F), internal energy(E), entropy(S), and specific heat capacity(Cv) from the phonon density of states. Various optical parameters are also calculated. The reflectance spectrum shows that this compound has the potential to be used as an efficient solar reflector.

关键词： mAX compound phonon dispersion thermodynamical properties optical properties

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综合技术教育的几个问题

人民教育 1953年第1期 36-44页

作者： m.h斯卡特金戍兵俄羅斯共和国教育科学院通讯院士

一最近時期,在敎育刊物上,在學校領導人員和教師們的會議上,在科學會議和研究會上,都經常並且頑強地提出關於綜合技術敎育與培養學生們的未來實際活動問題。當然,這不是偶然的。普通教育學校,負責培養青年一代的生活,而青年們在生活中,... 详细信息

一最近時期,在敎育刊物上,在學校領導人員和教師們的會議上,在科學會議和研究會上,都經常並且頑強地提出關於綜合技術敎育與培養學生們的未來實際活動問題。當然,這不是偶然的。普通教育學校,負責培養青年一代的生活,而青年們在生活中,會遇到極其複雜的各式各樣的器械:電燈、收音機、各種機器、機械、車床、測量器、器具等;也會遇到勞動組織中先進的方法和形式。青年們為了順利掌握這些技術,就應當很好地理解社會主義生產的科學原則,並能操縱最普通的器具、工具、儀器、機械,掌握生產勞動的最重要的技能和熟練技巧。綜合技術教育便是解決這項任務的手段之一。目前,學生的綜合技術教育,進行得不能令人滿意,以致學生們從學校畢業之後,一遇到實際工作,就經常表現得對勞動的準備很差。這便引起工業、農業、運輸及其它國民經濟部門的工作者,對學校提出合理的要求。

关键词：教育家教育工作者青年一代工案生庄普通教育华校改造自然

A COUPLED SYSTEm OF INTEGRAL EQUATIONS IN REFLEXIVE BANACh SPACES

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Acta mathematica Scientia 2012年第5期32卷 2021-2028页

作者： A.m.A.El-Sayed h.h.G.hashem Faculty of Science Alexandria UniversityAlexandriaEgypt Collage of Science & Arts Qassim UniversityBuraidahSaudi Arabia

We present an existence theorem for at least one weak solution for a coupled system of integral equations of Volterra type in a reflexive Banach spaces relative to the weak topology.

关键词： weak solution Volterra integral equation coupled system

Astrophysical S-factor of the d（p,γ）~3 he process by effective field theory

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Chinese Physics C 2013年第4期37卷 51-56页

作者： h.Sadeghi h.Khalili m.Godarzi Department of Physics Faculty of ScienceArak University

We summarize the recent effective field theory （EFT） studies of low-energy electroweak reactions of astrophysical interest, relevant to big-bang nucleosynthesis. The zero energy astrophysical S（0） factor for the thermal proton radiative capture by deuteron is calculated with pionless EFT. The astrophysical S（0） factor is accurately determined to be S（0）=0.243 eV·b up to the leading order （LO）. At zero energies, magnetic transition m1 gives the dominant contribution. The m1 amplitude is calculated up to the LO. A good, quantitative agreement between theoretical and experimental results is found for all observables. The demonstrations of cutoff independent calculation have also been presented.

关键词： proton-deutron radiative capture effective field theory cross section astrophysical S-factor

Novel typology of accelerated carbonation curing:using dry and pre-soaked biochar to tune carbon capture and mechanical properties of cementitious mortar

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Biochar 2023年第1期5卷 621-640页

作者： h.W.Kua S.m.h.Tan Department of the Built Environment College of Design and EngineeringNational University of SingaporeSingaporeSingapore

One of the challenges of promoting accelerated carbonation curing(ACC)of concrete as a carbon sequestration strategy is ensuring that carbonation will not deteriorate mechanical *** study examined the mechanical strength,water sorptivity and carbonation efficiency of ten types of mortar containing dry or pre-soaked biochar subjected to internal and/or external *** results obtained enabled a typology of ACC to be proposed,in which the carbon dioxide absorption of mortar containing various types of CO_(2)-dosed biochar ranged between 0.022%and 0.068%per unit dosage *** particular,the mortar containing dry biochar dosed with carbon dioxide was the top candidate for concurrently increasing both compressive strength(54.9 mPa)and carbon dioxide absorption(0.055%per unit dosage hour).mortar containing pre-soaked biochar dosed with carbon dioxide was identified as a strategy that achieved the highest carbonation efficiency(0.068%per unit dosage hour),but it also reduced compressive strength(45.1 mPa).Collectively,the proposed typology offers a useful overview of the different ways by which biochar can be used to tune ACC in mortar,according to any technical constraints and/or intended functions of the carbonated concrete components.

关键词： Biochar Pre-soaked Carbonation effectiveness Carbonation efficiency Accelerated carbonation curing

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四象限开关电容DC/DC罗氏变换器

电源技术应用 1999年第3期2卷 4-10页

作者：罗方林叶虹 Rashid m.h 南洋理工大学EE学院南洋道新加波639798 西安交通大学西安710049 西佛罗里达大学

经典的DC/DC变换器,如Buck变换器,Boost变换器,Buck-Boost变换器,罗氏变换器和Cuk变换器,通常都是由电感和电容组成,所以它们的尺寸大且功率密度低。开关电容已被成功地应用于无感DC/DC变换器中,开拓了设计高功率密度变换器的方法。然而... 详细信息

经典的DC/DC变换器,如Buck变换器,Boost变换器,Buck-Boost变换器,罗氏变换器和Cuk变换器,通常都是由电感和电容组成,所以它们的尺寸大且功率密度低。开关电容已被成功地应用于无感DC/DC变换器中,开拓了设计高功率密度变换器的方法。然而,在文献中已有的多数变换器都是单象限运行。其中一些变换器工作在推挽状态下,它们的控制电路和拓朴是很复杂的。本文介绍一种四象限开关电容DC/DC罗氏变换器。文中的分析和计算已得到试验测试结果的验证。

关键词：四象限运行开关电容电压举升技术直流变换器

Effect of samarium oxide on structural,optical and electrical properties of some alumino-borate glasses with constant copper chloride

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Journal of Rare Earths 2020年第7期38卷 770-775,I0004页

作者： m.S.Sadeq h.Y.morshidy Basic Sciences Dept. Faculty of EngineeringSinai Univ.45511Al-ArishEgypt

The glass system under study was prepared and examined using the melt quenching procedures and XRD to em.hasize the amorphous nature,*** of the prepared solid glass system was performed by a spectrophotometer in wavelengths from 190 to 1099 *** traditional techniques and standard formulas,the density,molar volume,refractive index,optical band gap and the optical filter characteristics were determined,then the influence of samarium oxide on some properties like the structure and optical,also the electrical properties were dissected.A novel formula was proposed to estimate the refractive index from the optical energy *** obtained samples are good optical filters especially the sample that contains 0.8 mol% of Sm2 *** this sample has the utmost density,the least molar volume,the maximum transmittance,least refractive index,the highest optical band gap and the least dc conductivity.

关键词： Alumino borate glasses Samarium oxide Optical properties Rare earths