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L-shell x-ray fluorescence relative intensities for elements with 62≤Z≤83 at 18 keV and 23 keV by synchrotron radiation

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Chinese Physics B 2023年第8期32卷 270-273页

作者： M Alqadi S AL-humaidi h Alkhateeb f Alzoubi Department of Physics Jordan University of Science and TechnologyIrbidJordan

The relative intensities of L-subshell x-ray fluorescence(XRf)for elements with atomic numbers 62≤Z≤83 were measured at two excitation energies,18 keV and 23 keV,using a synchrotron radiation source at a beamline of the Synchrotron Light Center for Experimental Science and Applications in the Middle East(SESAME),*** experimentally measured results of the relative intensities were compared with the calculated results using the subshell fluorescence yield and the Coster-Kronig transition probabilities recommended by Campbell and the values based on the Dirac-hartree-Slater model by *** experimental and theoretical results are in *** this work,L XRf relative intensities for the elements Sm,Gd,Tb,Er,Ta,W,Re,hg,Pb and Bi at energies of 18 keV and 23 keV were measured.

关键词： L shell x-ray fluorescence(XRf) relative intensities synchrotron radiation

f(T,B)gravity with statistically fitting of h(z)

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Communications in Theoretical Physics 2023年第9期75卷 79-90页

作者： S h Shekh N Myrzakulov A Bouali A Pradhan Department of Mathematics S.P.M.Science and Gilani ArtsCommerce CollegeGhatanjiYavatmalMaharashtra 445301India L.N.Gumilyov Eurasian National University Astana 010008Kazakhstan Ratbay Myrzakulov Eurasian International Center for Theoretical Physics Astana010009Kazakhstan Laboratory of Physics of Matter and Radiation Mohammed I UniversityBP 717OujdaMorocco Centre for Cosmology Astrophysics and Space Science(CCASS)GLA UniversityMathura-281406Uttar PradeshIndia

Some recent developments(accelerated expansion)in the Universe cannot be explained by the conventional formulation of general *** apply the recently proposed f(T,B)gravity to investigate the accelerated expansion of the *** parametrizing the hubble parameter and estimating the best fit values of the model parameters b_(0),b_(1),and b_(2)imposed from Supernovae type la,Cosmic Microwave Background,B aryon Acoustic Oscillation,and hubble data using the Markov Chain Monte Carlo method,we propose a method to determine the precise solutions to the field *** then observe that the model appears to be in good agreement with the observations.A change from the deceleration to the acceleration phase of the Universe is shown by the evolution of the deceleration *** addition,we investigate the behavior of the statefinder analysis,equation of state(EoS)parameters,along with the energy ***,to discuss other cosmological parameters,we consider some wellknown f(T,B)gravity models,specifically,f(T,B)=aT^(b)+cB^(d).Lastly,we find that the considered f(T,B)gravity models predict that the present Universe is accelerating and the EoS parameter behaves like the ACDM model.

关键词： isotropic homogeneous space-time f(T,B)gravity statistical fitting of h(z)data cosmology

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半导体缺陷电子学

半导体缺陷电子学

Diameter-dependent in vitro performance of biodegradable pure zinc wires for suture application

作者： h.f.·马瑞特(h.f. Matare)

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Journal of Materials Science & Technology 2019年第8期35卷 1662-1670页

作者： h. Guo R.h. Cao Y.f. Zheng J. Bai f. Xue C.L. Chu State Key Laboratory for Turbulence and Complex System and Department of Materials Science and Engineering College of Engineering Peking University Beijing 100871 China School of Materials Science and Engineering Southeast University Nanjing 211189 China Key Laboratory for Advanced Metallic Materials Southeast University Nanjing 211189 China

In this study, biodegradable pure zinc wires with 3.0 mm and 0.3 mm in diameter were prepared via hot-extrusion and subsequent cold-drawing process respectively. The microstructure, mechanical performance, corrosion behavior, in vitro cytocompatibility and antibacterial effect were comparatively *** cold-drawing, the mechanical property, especially the elongation of the ф0.3 mm pure Zn wire was improved significantly compared with the ф3.0 mm pure Zn wire. The in vitro corrosion study including immersion and electrochemical test showed acceptable corrosion resistance of these two materials in hank's solution. The in vitro human Umbilical Vein Endothelial Cells(hUVECs) viability assay showed obviously different results, in which the ф0.3 mm pure Zn wire demonstrated favorable cytocompatibility, while the ф3.0 mm wire exhibited severe cytotoxic effect with 100% extract concentration. Both of them exhibited partly antibacterial effect on S. aureus. These results demonstrated the feasibility of the prepared 0.3 mm pure Zn wire as the potential suture material with good absorbability.

关键词： Pure zinc Wire Biodegradable metal Suture

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防空計算系統可靠元件的研制

电子计算机动态 1959年第2期 58-60页

作者： h.f.海斯

引言高速电子数字計算机的可靠性与很多因素有关,其中之一就是組成系統的电子元件的性能。本文旨在討論一个关于电子元件可靠性的計划。这个計划首先要研制能滿足防空計算机需要的电子元件。系統的要求用在电子系統中元件的型号及質量... 详细信息

引言高速电子数字計算机的可靠性与很多因素有关,其中之一就是組成系統的电子元件的性能。本文旨在討論一个关于电子元件可靠性的計划。这个計划首先要研制能滿足防空計算机需要的电子元件。系統的要求用在电子系統中元件的型号及質量在很大程度上决定于該系統运行的要求。目前这

关键词：电子元件元件寿命可靠元件

Rapid Growth of TiNi intermetallic compound within undercooled Ti_(50)Ni_(50)alloy under electrostatic levitation condition

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Journal of Materials Science & Technology 2021年第18期77卷 82-89页

作者： P.f.Zou C.h.Zheng L.hu h.P.Wang School of Physical Science and Technology Northwestern Polytechnical University.Xi'an710072China

The undercooling dependence of the solidification mechanism was systematically explored by the electrostatic levitation(ESL)*** the experiments,the maximum undercooling reached up to 406 K(0.26 T_L)and the growth velocity of the primary TiNi phase was in-situ determined at various *** the initial increase of alloy undercooling,the value of growth velocity sluggishly rose followed by a power *** this case,the primary TiNi phase preferentially developed as the equiaxed dendrite,then the remnant liquid participated as Ti_(2)Ni andα-Ti phases on the grain *** the undercooling exceeded the critical value of 350 K,the growth velocity of the primary phase displayed a sharply increase ***,the TEM results demonstrated that the precipitation of the intermetallic Ti_(2)Ni compound was gradually restrained during the rapid solidification and the R-phase existing in the TiNi matrix at large undercooling implied that the martensitic transformation was incomplete.

关键词： Undercooling Ti-Ni alloy Solidification Growth kinetics

Improving the performance of structure-embedded acoustic lenses via gradient-index local inhomogeneities

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International Journal of Smart and Nano Materials 2015年第1期6卷 1-13页

作者： h.Zhu f.Semperlotti Department of Aerospace and Mechanical Engineering University of Notre DameNotre DameIndiana 46556USA

We investigate the use of graded inhomogeneities in order to enhance the focusing and collimation performance of structure-embedded acoustic metamaterial *** type of inhomogeneity exploited in this study consists in axial symmetric exponential-like gradients of either material or geometric properties that create gradient-index inclusions able to bend and redirect propagating *** particular,we exploit the concept of gradient index inclusions to achieve focusing and collimation of ultrasonic beams created by embedded drop-channel lenses in both bulk and thin-walled *** the latter,the implementation is possible thanks to geometric exponential tapers known as Acoustic Black holes(ABh).ABh tapers allow accurate control of the characteristics of the acoustic beam emanating from the lens channel which in the conventional design is severely affected by *** concept of beam control via graded inclusions is numerically illustrated and validated by using a combination of methodologies including geometric acoustics,finite difference time domain,and finite element methods.

关键词： acoustic lens acoustic black hole gradient index inhomogeneity drop-channel acoustic metamaterials

Predictive fatigue crack growth law of high-strength steels

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Journal of Materials Science & Technology 2022年第5期100卷 46-50页

作者： h.f.Li P.Zhang B.Wang Z.f.Zhang Laboratory of fatigue and fracture for Materials Shi-changxu Innovation Center for Advanced MaterialsChinese Academy of SciencesInstitute of Metal ResearchShenyang 110016China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China

The fatigue resistance of metallic materials is generally attributed to both strength and ***,these properties are mutually exclusive in most *** theories like Paris’law only provide some data correlation schemes rather than a predictive capability,which cannot satisfactorily guide the anti-fatigue *** this study,for the first time,the predictive fatigue crack growth rate law is proposed by considering the effects of both strength and ***,a quantitative criterion is established for judging the fatigue crack resistance of high-strength *** predictive law would provide a unique view to the quantitative anti-fatigue design of metallic materials.

关键词： fatigue crack growth Strength and toughness Paris’law high-strength steels

Synthesis of some new fused coumarin derivatives

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Chinese Journal of Chemistry 2000年第4期18卷 590-595页

作者： EL-DEEN Ibrahim Mohey IBRAhIM h.K. MAhMOUD f.f. faculty of Education Suez Canal University Port-Said EgyptFaculty of Science Suez Canal University Ismailia EgyptFaculty of Science (for Girls) Al-Azhar University Nasr City Egypt

2-hydrazino-4-hydroxy-5h-[1]-benzopyrano-[4,3-d]-pyrimidin-5-one (3) was prepared via condensation of 2 with hydrazine hydrate. Treatment of 3 with methylene chloride, ethyl chloroformate, ethyl chloroacetate and benzaldehyde yielded the corresponding 2 - ( substituted ) hydrazino - 4 -hydro-xy-5h-[1]-benzopyrano-[4,3-d]-pyrimidin-5-one (4, 5, 6, and 10), followed by cyclization of 4, 5 and 6 with dimethyl formamide and fused sodium acetate under reflux, while compound 10 was cyclized with bromine and sodium acetate in acetic acid. Compound 3 reacted with β-(toloyl) acrylic acid, ethyl α-cyano-p-methoxycinnamate, diethyl malonate and acetyl chloride affording the corresponding 2-(substituted) hydrazino-4-hydroxy-5h-[1]-benzopyrano-[4,3-d]-pyrimidin-5-one (12, 13, 14, 15 and 16).

关键词： Synthesis fused coumarin derivatives cyclization