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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

Mathematical modeling of mixed convective MHD falkner-skan squeezed sutterby multiphase flow with non-fourier heat flux theory and porosity

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Applied Mathematics and Mechanics(English Edition) 2023年第11期44卷 2005-2018页

作者： shuguang LI M.I.KHAN f.ALI s.s.ABDULLAEV s.sAADAOUI HABIBULLAH school of Computer science and Technology Shandong Technology and Business UniversityYantai 264005Shandong ProvinceChina Department of Mechanics and Engineering science Peking UniversityBeijing 100871China Department of Mechanical Engineering Lebanese American UniversityBeirut 11020Lebanon Department of Mathematical sciences Federal Urdu University of ArtsSciences&TechnologyGulshan-e-IqbalKarachi 75300Pakistan faculty of Chemical Engineering New Uzbekistan UniversityTashkent 100070Uzbekistan Department of science and Innovation Tashkent State Pedagogical University named after NizamiTashkent 100070Uzbekistan Department of Physics Faculty of Science and ArtsMohayel AserKing Khalid UniversityAbha 61421Saudi Arabia state Key Laboratory of Turbulence and Complex system Collaborative Innovative Center for Advanced Aero-EnginesPeking UniversityBeijing 100871China

In a wide variety of mechanical and industrial applications,e.g.,space cooling,nuclear reactor cooling,medicinal utilizations(magnetic drug targeting),energy generation,and heat conduction in tissues,the heat transfer phenomenon is ***’s law of heat conduction has been used as the foundation for predicting the heat transfer behavior in a variety of real-world *** model’s production of a parabolic energy expression,which means that an initial disturbance would immediately affect the system under investigation,is one of its main ***,numerous researchers worked on such problem to resolve this *** last,this problem was resolved by Cattaneo by adding relaxation time for heat flux in fourier’s law,which was defined as the time required to establish steady heat conduction once a temperature gradient is *** offered a material invariant version of Cattaneo’s model by taking into account the upper-connected derivative of the Oldroyd ***,both models are combinedly known as the Cattaneo-Christov(CC)*** this attempt,the mixed convective MHD falkner-skan sutterby nanofluid flow is addressed towards a wedge surface in the presence of the variable external magnetic *** CC model is incorporated instead of fourier’s law for the examination of heat transfer features in the energy expression.A two-phase nanofluid model is utilized for the implementation of *** nonlinear system of equations is tackled through the bvp4c technique in the MATLAB software *** influence of pertinent flow parameters is discussed and displayed through different *** and important results are summarized in the conclusion ***,in both cases of wall-through flow(i.e.,suction and injection effects),the porosity parameters increase the flow speed,and decrease the heat transport and the influence of drag forces.

关键词： sporosity Cattaneo-Christov(CC)heat flux model falkner-skan sutterby nanofluid mixed convection stagnation point

NiTi laser textured implants with improved in vivo osseointegration:An experimental study in rats

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Journal of Materials science & Technology 2022年第19期114卷 120-130页

作者： M.M.Costa A.Miranda f.Bartolomeu O.Carvalho s.Matos G.Miranda f.s.silva Center for MicroElectroMechanical systems(CMEMs-UMinho) University of MinhoCampus de AzurémGuimarães 4800-058Portugal Life and Health sciences Research Institute(ICVs) School of MedicineUniversity of MinhoCampus de GualtarBraga 4710-057Portugal ICVs/3B’s-PT Government Associate Laboratory Braga/GuimarãesPortugal Center for Innovation and Research in Oral sciences(CIROs) Faculty of MedicineUniversity of CoimbraFMUCPortugal CICECO Aveiro Institute of MaterialsDepartment of Materials and Ceramic EngineeringUniversity of AveiroAveiro 3810-193Portugal

Laser surface texturing is a versatile approach for manufacturing implants with suitable surfaces for *** work explores the use of laser to fabricate NiTi textured implants,testing two dif-ferent groove-based *** performance was evaluated in vivo through implantation in sprague Dawley rats’femur,being then analyzed after 4 and 12 weeks of ***-out experiments and histological characterization allowed to assess bone-implant bond and osseointegration and to compare the laser textured solutions with non-textured *** showed that,at 4 weeks of implantation,mainly immature woven bone was present whilst at 12 weeks a more mature bone had ***-sidering the largest implantation time(12 weeks),results showed extraction forces considerably higher for textured implants(G2 and G3).Moreover,when comparing G2 and G3,it was found that G2(having the highest textured surface area)displayed the maximum extraction force among all groups,with an increase of 212%when compared to non-textured implants(G1).These results prove that the design and manufacturing technology are effective to promote an im-proved bone-implant bond,aiming the development of orthopedic implants.

关键词： NiTi Laser surface texturing In vivo studies Osseointegration Implants

New Aspects of field Entropy squeezing as an Indicator for Mixed state Entanglement in an Effective Two-Level system with stark shift

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Chinese Physics Letters 2011年第12期28卷 24-27页

作者： s.Abdel-Khalek M.M.A.Ahmed A-s f.Obada Department of Mathematics Faculty of ScienceSohag University82524 SohagEgypt Department of Mathematics Faculty of ScienceTaif University21974 TaifSaudi Arabia Department of Mathematics Faculty of ScienceAl-Azhar UniversityNasr City11884 CairoEgypt

We present an effective two-level system in interaction through two-photon processes with a single mode quantized electromagnetic field,initially prepared in a coherent *** entropy squeezing as an indicator of the entanglement in a mixed state system is *** temporal evolution of the negativity,Wehrl entropy,Wehrl phase distribution and field entropy squeezing are *** results highlight the important roles played by both the stark shift parameters and the mixed state setting in the dynamics of the Wehrl entropy,Wehrl phase distribution and field entropy squeezing.

关键词： state entropy system

Characterization of MCrAlY/nano-Al_(2)O_(3) nanocomposite powder produced by high-energy mechanical milling as feedstock for high-velocity oxygen fuel spraying deposition

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International Journal of Minerals,Metallurgy and Materials 2021年第9期28卷 1534-1543页

作者： f.Ghadami A.sabour Rouh Aghdam s.Ghadami Department of Materials Engineering Tarbiat Modares UniversityP.O.Box 14115-143TehranIran

Al_(2)O_(3) nanoparticles and MCrAlY/nano-Al_(2)O_(3) nanocomposite powder(M=Ni,Co,or NiCo)were produced using high-energy ball *** MCrAlY/nano-Al_(2)O_(3) coating was deposited by selecting an optimum nanocomposite powder as feedstock for high-velocity oxy-gen fuel thermal *** morphological and microstructural examinations of the Al_(2)O_(3) nanoparticles and the commercial MCrAlY and MCrAlY/nano-Al_(2)O_(3) nanocomposite powders were investigated using X-ray diffraction analysis,field-emission scanning electron microscopy coupled with electron dispersed spectroscopy,and transmission electron *** structural investigations and Williamson-Hall res-ults demonstrated that the ball-milled Al_(2)O_(3) powder after 48 h has the smallest crystallite size and the highest amount of lattice strain among the as-received and ball-milled Al_(2)O_(3) owing to its optimal nanocrystalline *** the case of developing MCrAlY/nano-Al_(2)O_(3) nanocompos-ite powder,the particle size of the nanocomposite powders decreased with increasing mechanical-milling duration of the powder mixture.

关键词： MCrAlY Nanocomposite powder High-energy mechanical milling Williamson-Hall analysis HVOf coating

Magnetization of Gd diffused YBa_2Cu_3O_(7-x) superconductor:Experiment and theory

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Chinese Physics B 2013年第7期22卷 489-493页

作者： f. Inanir s. Yildiz K. Ozturk s. Celebi Department of Physics Art and Science FacultyRecep Tayyip Erdogan University Department of Metallurgical and Materials Engineering Ahi Evran University Department of Physics Karadeniz Technical University

The magnetization of Gd diffused YBa2Cu3O7-x is measured by a vibrating sample magnetometer （VsM） at selected temperatures （5, 25, 50, 77 K）. The experimental results for the magnetization are analyzed in the critical state framework involving Kim-Anderson field dependence Jc（H）=Jc0/（1＋｜H｜/H0）n of critical current density and equilibrium magnetization M eq . It is found that the inclusion of the equilibrium magnetization becomes more important at higher temperatures. At 77 K, the shape of the isothermal M-H hysteresis curve is governed by the equilibrium magnetization. some superconducting parameters are determined by fitting the calculated curves to the experimental data.

关键词： type-II superconductor YBCO surface effect equilibrium magnetization critical-state model

A dive into spectral inference networks: improved algorithms for self-supervised learning of continuous spectral representations

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Applied Mathematics and Mechanics(English Edition) 2023年第7期44卷 1199-1224页

作者： J.WU s.f.WANG P.PERDIKARIs Graduate Group in Applied Mathematics and Computational science University of Pennsylvania PhiladelphiaPA 19104U.S.A. Department of Mechanical Engineering and Applied Mechanics University of Pennsylvania PhiladelphiaPA 19104U.S.A.

We propose a self-supervising learning framework for finding the dominant eigenfunction-eigenvalue pairs of linear and self-adjoint *** represent target eigenfunctions with coordinate-based neural networks and employ the fourier positional encodings to enable the approximation of high-frequency *** formulate a self-supervised training objective for spectral learning and propose a novel regularization mechanism to ensure that the network finds the exact eigenfunctions instead of a space spanned by the ***,we investigate the effect of weight normalization as a mechanism to alleviate the risk of recovering linear dependent modes,allowing us to accurately recover a large number of *** effectiveness of our methods is demonstrated across a collection of representative benchmarks including both local and non-local diffusion operators,as well as high-dimensional time-series data from a video *** results indicate that the present algorithm can outperform competing approaches in terms of both approximation accuracy and computational cost.

关键词： spectral learning partial differential equation(PDE) neural network slow features analysis

Identification of Diabetic Retinal Exudates in Digital Color Images Using support Vector Machine

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Journal of Intelligent Learning systems and Applications 2013年第3期5卷 135-142页

作者： R. f. mansour E. Md. Abdelrahim Amna s. Al-Johani Department of Computer science Faculty of Science Northern Borders University Arar Saudi Arabia Department of Mathematics Faculty of Science Northern Borders University Arar Saudi Arabia.

support vector machine (sVM) has become an increasingly popular tool for machine learning tasks involving classification. In this paper, we present a simple and effective method of detect and classify hard exudates. Automatic detection of hard exudates from retinal images is worth-studying problem since hard exudates are associated with diabetic retinopathy and have been found to be one of the most prevalent earliest signs of retinopathy. The algorithm is based on Discrete Cosine Transform (DCT) analysis and sVM makes use of color information to perform the classification of retinal exudates. We prospectively assessed the algorithm performance using a database containing 1200 retinal images with variable color, brightness, and quality. Results of the proposed system can achieve a diagnostic accuracy with 97.0% sensitivity and 98.7% specificity for the identification of images containing any evidence of retinopathy.

关键词： Hard Exudates Diabetic Retinal support Vector Machine Discrete Cosine Transform

separation of ^(152+154)Eu,^(90)sr from radioactive waste effluent using liquid–liquid extraction by polyglycerol phthalate

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Nuclear science and Techniques 2018年第6期29卷 76-84页

作者： M.f.Attallah s.E.Rizk s.A.shady Analytical Chemistry and Control Department Hot Laboratories Center Atomic Energy Authority of Egypt Chemistry of Nuclear fuel Department Hot Laboratories Center Atomic Energy Authority of Egypt Technology of Nuclear fuel Department Hot Laboratories Center Atomic Energy Authority of Egypt

A new polyglycerol phthalate extractant was prepared and characterized using fourier transform infrared spectroscopy, proton nuclear magnetic resonance(~1H NMR) spectroscopy, and thermogravimetric analysis. A preliminary study of the extraction of long-lived(^(90) sr and ^(152+154)Eu) and short-lived(^(90) Y) radionuclides by polyglycerol phthalate was performed. The influence of different diluents, concentration of the acid, type of acid, and various interfering ions was explored. The stripping of ^(152+154)Eu radionuclide was studied by using different acid solutions, and it was found that sulfuric acid was the ideal acid for this purpose. furthermore,^(152+154)Eu was extracted from the fission products(^(90) sr) and the extraction% of^(90) sr was found to improve in the presence of interfering ions.

关键词：放射性核种抽取液体 fourier 分离浪费光谱学 NMR

Do vegetative and reproductive phenophases of deciduous tropical species respond similarly to rainfall pulses?

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Journal of forestry Research 2013年第4期24卷 643-651页

作者： A.P.silveira f.s.Araújo f.R.Martins Itapipoca faculty of Education Av.Monsenhor Tabosa s/ no.Ceará State University -- UECE Graduate Course of Ecology and Natural Resources Department of BiologyBuilding 906Federal University of Ceará-UFC Department of Plant Biology Institute of BiologyP.O.Box 610University of Campinas – UNICAMP

Deciduous trees with high-density wood that occur in dry seasonal tropical regions respond to rainfall seasonality with synchrony in phenophases. However, they may exhibit interannual differences in synchrony and intensity of phenophases, as strategy for large variations in duration and intensity of rainfall pulses. Nevertheless, it remains unknown how phenophases of deciduous trees of the Brazilian semi-arid region respond to rainfall variations. The phenology of Cordia oncocalyx was monitored in deciduous thorny woodland （Caatinga）, from April 2009 to March 2011, and was correlated with rainfall, soil humidity, temperature, and photoperiod. The rainy years 2009 and 2011 exhibited higher duration of rainfall pulses and lower frequency of interpulses, but in 2010 pulse duration and total rainfall were lower. Circular statistics showed leaf flush followed by flowering and fruiting in the rainy season, and leaf fall and seed dispersal in the dry season.

关键词： asynchrony circular analysis deciduous phenology riskspreading seasonality.