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microstructure of Cu-based amorphous Composite Coatings on AZ91D magnesium Alloy by Laser Cladding

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Journal of materials Science & technology 2009年第4期25卷 492-498页

作者： Kaijin Huang Changsheng Xie t.m. Yue State Key Laboratory of Advanced Welding Production technology Harbin Institute of Technology Harbin 150001 China State Key Laboratory of materials Processing and Die ＆ mould technology Huazhong University of Scienee and Technology Wuhan 430074 China Department of Industrial and Systems Engineering Hong Kong Polytechnic University Hung Horn Hong Kong China

to improve the sliding wear resistance of AZ91D magnesium alloy, Cu-based amorphous composite coatings made of Cuatti34Zr11Nis and Cu47ti34Zr11Ni8＋20 wt pct SiC powders were fabricated on AZ91D magnesium alloy by laser cladding, respectively. SEm （scanning electron microscopy）, EDS （energy dispersive X-ray spectroscopy）, XRD （X-ray diffraction） and tEm （transmission electron microscopy） techniques were employed to study the phases of the coatings. the results show that the coatings mainly consist of amorphous phase and different intermetallic compounds. the reason of formation of amorphous phase and the function of SiC particles were explained in details.

关键词： Laser cladding Cu-based amorphous composite coating SiC particle AZ91D magnesium alloy

High-frequency induction heated sintering of ball milled Fe-WC nanocomposites

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International Journal of minerals,metallurgy and materials 2013年第7期20卷 693-699页

作者： m. Zakeri t. Zanganeh A. Najafi Ceramic Department Materials and Energy Research Center P.O. Box 31787/316 Karaj Iran Department of materials Saveh Branch Islamic Azad University Saveh Iran

Fe-WC nanocomposites were successfully fabricated by high-frequency induction heated sintering of ball milled nanostructure powders. the ball milled powders were characterized by X-ray diffraction. Density measurements by the Archimedes method show that all sintered samples have the relative density higher than 95%. Studies on the effects of WC content, milling speed, and milling time indicate that a higher milling speed and a more WC content lead to the improvement of mechanical properties. there is a very good distribution of WC particles in the Fe matrix at the milling speed of 650 r/rain. For the sintered sample 20-5-650 （20wt% WC, milling time of 5 h, and milled speed of 650 r/min）, the maximum Brinell hardness and yield stress are obtained to be 3.25 GPa and 858 mPa, respectively. All sintered samples have brittle fracture during compression test except the sample 20-5-650.

关键词： nanocomposites metallic matrix composites iron tungsten carbide induction heating sintering mechanicalproperties

Partial slip effects in flow over nonlinear stretching surface

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Applied mathematics and mechanics(English Edition) 2015年第11期36卷 1513-1526页

作者： t.HAYAt m.ImtIAZ A.ALSAEDI Department of mathematics Quaid-i-Azam University 45320Islamabad 44000 Pakistan Department of mathematics Faculty of Science King Abdulaziz University

the two-dimensional flow of a viscous nanofluid is investigated. the flow is caused by a nonlinear stretching surface with the slip effects of the velocity, the temperature, and the concentration. the fluid is electrically conducted in the presence of an applied magnetic field. Appropriate transformations reduce the nonlinear partial differential system to an ordinary differential system. the convergent solutions of the governing nonlinear problems are computed. the results of the velocity, the temperature, and the concentration fields are calculated in series forms. the effects of the different parameters on the velocity, the temperature, and the concentration profiles are shown and analyzed. the skin friction coefficient, the Nusselt number, and the Sherwood number are also com-puted and investigated for different embedded parameters in the problem statements.

关键词： magnetohydrodynamic (mHD) nanofluid nonlinear stretching sheet slipeffect

QCD sum rule study of J^(P)=1^(±)exotic states with two heavy quarks in the molecular picture

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Chinese Physics C 2024年第6期48卷 31-37页

作者： t.m.Aliev S.Bilmis m.Savcı Department of Physics Middle East Technical UniversityAnkara06800Turkey tUBItAK ULAKBIm Ankara06510Turkey

In this study,the spectroscopic parameters of exotic molecular states composed of mesons containing two heavy quarks(scalar-axial and pseudoscalar-axial meson combinations)are investigated within the QCD sum *** findings reveal that molecular states containing charm quarks do not form bound states,whereas states with b-quarks can form exotic molecular *** observation has significant implications for understanding the structure of these exotic states.

关键词： QCD sum rules exotic mesons molecular states

γ-Irradiation Effect:Variation of Photosynthetic Activity of Euglena

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Biomedical and Environmental Sciences 2002年第3期15卷 261-267页

作者： t·SAKASHItA m·DOI 等 NationalInstituteofRadinologicalSciences

Objective to study the effects of gamma-ray irradiation on carbon fixation (Specific production rate: SPR), CO2 utilization efficiency (CUE) and electron transfer rate (EtR) in the photosynthetic flagellate Euglena gracilis strain Z in a dose-response dependent manner. methods Euglena cells were cultured in an inorganic nutrient medium containing ammonium chloride or proteose peptone. Cells were exposed to gamma-ray at 5 doses (0, 100, 250, 350, 500 Gy for water). Five days after irradiation, three photosynthetic activities were measured. SPR, which is a carbon uptake rate per unit carbon mass, was determined by 13C tracer methodology. CUE was evaluated using a relation of carbon isotope fractionation in Calvin cycle. EtR in photosystem II (PS II) was measured by a chlorophyll fluorescence analysis. Results Even at a dose of 500 Gy, 80 % of EtR of the non-irradiated control (0 Gy) was sustained, while SPR and CUE were about half the level in the non-irradiated control at 500 Gy. Furthermore, the dose response of EtR was considerably different from the others. Conclusion Our findings suggest that not only PS II but also the Calvin cycle in the photosynthetic system is affected by gamma ray irradiation.

关键词： Gamma-ray irradiation Euglena gracilis Photosynthetic activities

Does acid pickling of mg-Ca alloy enhance biomineralization?

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Journal of magnesium and Alloys 2021年第3期9卷 1028-1038页

作者： Shebeer A Rahim VP muhammad Rabeeh m A Joseph t Hanas Department of mechanical Engineering National Institute of Technology CalicutKerala 673601India Nanomaterials Research Laboratory School of Materials Science and EngineeringNational Institute of Technology CalicutKerala 673601India

the mechanical and physical properties of biodegradable magnesium(mg)alloys make them suitable for temporary orthopaedic *** success of these alloys depends on their performance in the physiological *** the present work,surface modification of mg-Ca binary alloy by acid pickling for better biomineralization and controlled biodegradation is *** corrosion rates of nitric and phosphoric acid treated samples were analysed by conducting electrochemical corrosion *** vitro degradation behaviour was studied using immersion test in simulated body fluid(SBF).the sample surfaces were characterized using scanning electron microscope(SEm),energy dispersive X-ray spectroscopy(EDS),Fourier transform infrared spectroscopy(FtIR)and X-ray photoelectron spectroscopy(XPS).It is seen that acid pickling leads to significant improvement in biomineralization and develop in situ calcium phosphate(Ca P)coating on the sample *** addition,the treated samples recorded a reduced degradation rate in the SBF compared to untreated ***,acid pickling is suggested as an effective surface treatment method to tailor the biomineralization and degradation behaviour of the mg-Ca alloy in the physiological environment.

关键词： Inorganic acid pickling magnesium alloy Surface pretreatment Surface characterization Biomineralization Degradation rate

Analysis of strong decays of SU(3)partners ofΩ(2012)baryon

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Chinese Physics C 2024年第8期48卷 34-41页

作者： t.m.Aliev S.Bilmis m.Savci Department of Physics Middle East Technical UniversityAnkara 06800Turkey tUBItAK ULAKBIm Ankara 06510Turkey

We estimate the coupling constants and decay widths of the SU(3)partners of theΩ(2012)hyperon,as discovered by the BELLE Collaboration,using the distribution amplitudes of the octet baryons within the light cone sum rules *** study includes a comparison of the obtained results for the relevant decay widths with those derived within the framework of the flavor SU(3)*** observe a good agreement between the predictions of both ***,our result on the decay width ofΩ→ΞK is compatible with the existing experimental result within the uncertainties of the model *** results can provide helpful insights for determining the nature of the SU(3)partners of theΩ(2012)baryon.

关键词： coupling constants light cone sum rule hyperon

Incorporation of europium (Ⅱ) nanostructures into the channels of mesoporous silicon oxy-nitride for enhanced photoluminescence

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Journal of Rare Earths 2018年第5期36卷 449-455页

作者： D. Suresh m. Yamashita t. Akai a National Institute for Advanced Industrial Science and technology （AISt） Kansai Center 1-8-31 Midorigaoka lkeda Osaka 563-8577 Japan 6 Department of Chemistry School of Chemical and Biotechnology SASTRA Deemed University Thanjavur 613 401 India

Divalent europium（Ⅱ）-doped mesoporous silicon oxy-nitride materials, as a novel type of nanoscopic photoluminescent material, are studied in which the optically active luminescent centers are isolated within the pores. Colorless and transparent blue emitting luminous Eu2＋-doped mesoporous silicon oxy-nitride materials were prepared from mesoporous silica via impregnation, nanocasting and nitrogen-assisted carbothermal reduction and nitridation method. the morphology and porosity of the silica remain unchanged during the synthesis process as revealed by SEm images and by nitrogen sorption studies. Photoluminescence studies reveal a strong blue emission band for Eu2＋ centered at 425 nm with a quantum efficiency of 47%. the luminescent intensity is greatly influenced by the amount of co-dopant, AI3＋ ions.

关键词： Blue luminescence Divalent europium mesoporous silicon oxy-nitride Carbothermal reduction and nitridation(CRN) Rare earths

Geometry-based mass grading of mango fruits using image processing

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Information Processing in Agriculture 2017年第2期4卷 150-160页

作者： m.A.momin m.t.Rahman m.S.Sultana C.Igathinathane A.t.m.Ziauddin t.E.Grift Department of Farm Power and machinery Bangladesh Agricultural UniversityMymensingh 2202Bangladesh Department of Agricultural and Biosystems Engineering North Dakota State University1221 Albrecht BoulevardFargoND 58102USA Department of Agricultural and Biological Engineering University of Illinois at Urbana-ChampaignUrbanaILUSA

mango(mangifera indica)is an important,and popular fruit in ***,the post-harvest processing of it is still mostly performed manually,a situation far from satisfactory,in terms of accuracy and *** automate the grading of mangos(geometry and shape),we developed an image acquisition and processing system to extract projected area,perimeter,and roundness *** this system,images were acquired using a XGA format color camera of 8-bit gray levels using fluorescent *** image processing algorithm based on region based global thresholding color binarization,combined with median filter and morphological analysis was developed to classify mangos into one of three mass grades such as large,medium,and *** system achieved an accuracy of 97% for projected area and Feret diameter,79% for perimeter,and 36% for *** achieve a finer grading,two different grading features could be used in *** image grading system is simple and efficient and can be considered a suitable first stage to mechanizing the commercial grading of mangos in ***,the method has the potential to be applied to other crops with suitable adjustments.

关键词： Horticultural crops Quality Sorting