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Effect of Oxidizing Atmosphere on the Surface of Titanium Dental Implant Material

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Journal of Bionic Engineering 2019年第6期16卷 1052-1060页

作者： Mohammad Khodaei akram Alizadeh Hamid Reza Madaah Hosseini Department of Materials Science and Engineering Golpayegan University of TechnologyGolpayegan 87717-65651Iran Department of Tissue Engineering School of Advanced TechnologiesShahrekord University of Medical SciencesShahrekord 88157-13471Iran Department of Materials Science and Engineering Sharif University of TechnologyTehran 14588-89694Iran

Direct oxidation is a simple and effective method for titanium surface *** this research,a titanium sample was directly oxidized at the high temperature in two different atmospheres,air and pure oxygen,to obtain better atmosphere for titanium surface *** results of the Raman spectroscopy indicated that in both atmospheres,the rutile bioactive phase(TiO2)has been formed on the titanium *** results of X-ray diffraction(XRD)also revealed that the surface of oxygen-treated sample was composed of the rutile phase and titanium monoxide(TiO),while at the surface of the air-treated sample,the rutile phase and titanium dioxide had been ***,the results of Field Emission Scanning Electron Microscopy(FE-SEM)showed that by the surface treatment of titanium in both atmospheres,some micro-features including cracks thinner than 30 nm were formed on the *** of more apatite forming ability and fewer water contact angle and more L-929 cell attachment of the air-treated titanium,it seemed that air,in comparison to the pure oxygen,is more promising atmosphere for the direct oxidation of titanium and improving its biofunctionalization.

关键词： titanium implant surface treatment direct oxidation anatase rutile biomedical-materials

Effect of gender on the reliability of COVID-19 rapid antigen test among elderly

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World Journal of Clinical Cases 2022年第29期10卷 10820-10822页

作者： Wassan Nori Wisam akram Department of Obstetrics and Gynecology Mustansiriyah UniversityBaghdad 10052Iraq Department of Obstetrics and Gynecology College of MedicineMustansiriyah UniversityBaghdad 10052Iraq

Defining con-founders that affect the reliability of diagnostic tests for coronavirus disease 2019 is vital to breaking the chain of *** elderly population is a higher risk group for the emerging ***,gender seems to exert a critical role in modifying the infection risk among women owing to hormonal *** menopause transition is an exceptional period for older women where the protective and immunomodulatory effects of the estrogen hormone are ***,attention should be given to postmenopausal women since they will have an increased risk compared to their pre-menopausal peers.

关键词： COVID-19 Rapid antigen test Real-time reverse transcription-polymerase chain reaction Age Gender Postmenopausal women

Calculations of ^(86)Y production via various nuclear reactions

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Nuclear Science and Techniques 2009年第6期20卷 369-372页

作者： SADEGHI Mahdi ZALI akram MOKHTARI Leila Agricultural Medical & Industrial Research School P.O. Box: 31485-498 Gohardast Karaj Iran Faculty of Engineering Research and Science Campus Islamic Azad University Tehran Iran Physics Faculty University of Zanjan P.O. Box: 45195/313 Zanjan Iran

This study obtains a suitable reaction to produce 86Y. The 86Y excitation functions via 86Sr(p,n)86Y, 86Sr(d,2n)86Y, 85Rb(3He,2n)86Y and 85Rb(α,3n)86Y reactions were calculated by TALYS-1.0 code and compared with the reported measurement. Requisite thickness of targets was obtained by SRIM code for each reaction. The 86Y production yield was evaluated with attention to excitation function and stopping power. The 86Sr(p,n)86Y reaction was determined as most interesting one due to its highest production yield and advantages to get high radionuclide and radiochemical purity.

关键词：核反应生产计算反应注射成型放射化学纯度放射性核素制动力激励

Natural Convection in a Horizontal Cylinder with Partial Heating: Energy Efficiency Analysis

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Journal of Thermal Science 2020年第6期29卷 1531-1550页

作者： MAZGAR akram JARRAY Khouloud HAJJI Fadhila BEN NEJMA Faycal The Higher Institute of Applied Sciences and Technology of Sousse University of SousseTunisia-Ibn Khaldun StreetTaffala City4003 SousseTunisia The Preparatory Institute for Engineering Studies of Monastir University of MonastirTunisia-Rue Ibn El Jazzar5019 MonastirTunisia

The current study reports a numerical analysis of free convection of air in an isothermal horizontal cylinder,cooled and heated at different wall *** heater sizes are discussed in this *** first heated zone is spread across one-quarter of the sidewall;the second is uniformly distributed over the half of the wall and the third active wall covers three-quarters of the *** various locations are considered and examined for each active zone of the *** computation is carried out for Rayleigh number ranging from 102 to *** results characterizing heat transfer and flow features are achieved using an iterative model developed in COMSOL *** effect of Rayleigh number on heat transfer and fluid flow characteristics within the cavity are *** attention is paid to the influence of heater location and heater size on energy *** is found that the mean Nusselt number and dimensionless velocity increase when increasing the Rayleigh ***,the optimal level of energy efficiency is achieved if the heating zone is centered at the upper part of the cylinder,regardless of the heater *** is also shown that the optimal configuration providing higher energy efficiency is obtained when three-quarters of the sidewall are locally heated,and more precisely,if the active zone is centered at the top of the cylinder.

关键词： natural convection cylinder partial heating energy efficiency Rayleigh number

Impact of air pressure variations on electrical vehicle motor insulation

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High Voltage 2023年第5期8卷 1011-1019页

作者： Peng Wang Chaofan Yu Shakeel akram Ziyuan Fan Wenhuan Zhao National Demonstration Base for Innovation Entrepreneurship New Energy and Electrical Insulation LaboratorySichuan UniversityChengduChina College of Electrical Engineering and Control Science Nanjing Tech UniversityNanjingChina

Variation in air pressure severely affects the insulation of electric vehicle(EV)motors,hence weakening the reliability of EVs for safe ***‐polyimide‐Nomex,a typical insulation material for EV motors,was used to investigate the motor insulation performance under different air *** results show that the partial discharge inception voltage is significantly reduced for EV motors operated at lower air pressures,and the probability of partial discharge(PD)occurrence is *** macroscopic results reveal that the active area of the PD expands at low pressure,while the non‐corroded ring appears in the ***,although the number and amplitude of the PD increase significantly with decrease in air pressure,the active area of the PD expands and electrical stress on the insulation per unit area increases ***,when the pressure decreased from 60 to 40 kPa,the endurance life does not show a significant downward ***,the dielectric constant and loss of the low‐pressure samples significantly change during the ageing process,which further indicates critical degradation of the *** aforementioned investigations reveal that the air pressure at different altitudes has a significant impact on the performance of insulation materials.

关键词： insulation electrical Impact

Estimation of hydraulic jump on corrugated bed using artificial neural networks and genetic programming

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Water Science and Engineering 2013年第2期6卷 189-198页

作者： akram ABBASPOUR Davood FARSADIZADEH Mohammad Ali GHORBANI Department of Water Engineering University of Tabriz

Artificial neural networks （ANNs） and genetic programming （GP） have recently been used for the estimation of hydraulic data. In this study, they were used as alternative tools to estimate the characteristics of hydraulic jumps, such as the free surface location and energy dissipation. The dimensionless hydraulic parameters, including jump depth, jump length, and energy dissipation, were determined as functions of the Froude number and the height and length of corrugations. The estimations of the ANN and GP models were found to be in good agreement with the measured data. The results of the ANN model were compared with those of the GP model, showing that the proposed ANN models are much more accurate than the GP models.

关键词： artificial neural networks genetic programming," corrugated bed, Froude number, hydraulic jump

Comparative Analysis of Pythagorean MCDM Methods for the Risk Assessment of Childhood Cancer

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Computer Modeling in Engineering & Sciences 2023年第6期135卷 2585-2615页

作者： Shaista Habib Muhammad akram MMAli Al-Shamiri School of Systems and Technology University of Management and TechnologyLahorePakistan Department of Mathematics University of the PunjabNew CampusLahorePakistan Department of Mathematics Faculty of Science and ArtsMahayl AssirKing Khalid UniversityAbhaSaudi Arabia

According to the World Health Organization(WHO),cancer is the leading cause of death for children in low and middle-income *** 400,000 kids get diagnosed with this illness each year,and their survival rate depends on the country in which they *** this article,we present a Pythagorean fuzzy model that may help doctors identify the most likely type of cancer in children at an early stage by taking into account the symptoms of different types of *** Pythagorean fuzzy decision-making techniques that we utilize are Pythagorean Fuzzy TOPSIS,Pythagorean Fuzzy Entropy(PF-Entropy),and Pythagorean Fuzzy PowerWeighted Geometric(PFPWG).Ourmodel is fed with nineteen symptoms and it diagnoses the risk of eight types of cancers in *** develop an algorithm for each method and calculate its ***,we consider an example to make a clear understanding of our *** also compare the final results of various tests that prove the authenticity of this study.

关键词： Risk assessment Pythagorean fuzzy sets TOPSIS method entropy power weighted geometric operators

Analog performance of double gate junctionless tunnel field effect transistor

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Journal of Semiconductors 2014年第7期35卷 37-41页

作者： M.W.akram Bahniman Ghosh Department of Electrical Engineering Indian Institute of Technology KanpurKanpurUttar Pradesh208016India Microelectronics Research Center 10100 Burnet RoadBldg.160University of Texas at AustinAustinTX78758USA

For the first time, we investigate the analog performance of n-type double gate junctionless tunnel field effect transistor （DG-JLTFET） and the results are compared with the conventional n-type double gate tunnel field effect transistor （DG-TFET） counterpart. Using extensive device simulations, the two devices are compared with the following analog performance parameters, namely transconductance, output conductance, output resistance, intrinsic gain, total gate capacitance and unity gain frequency. From the device simulation results, DG-JLTFET is found to have significantly better analog performance as compared to DG-TFET.

关键词： junctionless field effect transistor tunnel field effect transistor subthreshold slope

On the calibration of a shear stress criterion for rock joints to represent the full stress-strain profile

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 379-392页

作者： akram Deiminiat Jonathan D.Aubertin Yannic Ethier Department of Construction Engineering École de Technologie Supérieure(ÉTS)MontréalCanada

Conventional numerical solutions developed to describe the geomechanical behavior of rock interfaces subjected to differential load emphasize peak and residual shear *** detailed analysis of preand post-peak shear stress-displacement behavior is central to various time-dependent and dynamic rock mechanic problems such as rockbursts and structural instabilities in highly stressed *** complete stress-displacement surface(CSDS)model was developed to describe analytically the pre-and post-peak behavior of rock interfaces under differential *** formulations of the CSDS model required extensive curve-fitting iterations which limited its practical applicability and transparent integration into engineering *** present work proposes modifications to the CSDS model aimed at developing a comprehensive and modern calibration protocol to describe the complete shear stressdisplacement behavior of rock interfaces under differential *** proposed update to the CSDS model incorporates the concept of mobilized shear strength to enhance the post-peak ***’s concepts of joint roughness coefficient(JRC)and joint compressive strength(JCS)are incorporated to facilitate empirical estimations for peak shear stress and normal closure ***/uniaxial compression test and direct shear test results are used to validate the updated model and exemplify the proposed calibration *** results illustrate that the revised model successfully predicts the post-peak and complete axial stressestrain and shear stressedisplacement curves for rock joints.

关键词： Full shear profile Post-peak shear behavior Rock joint Joint roughness coefficient(JRC) Axial stress-strain curve