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Transactions of Nonferrous Metals Society of China 2020年第5期30卷 1169-1182页

作者： sultanöztürk Sefa Emre SÜNBÜL KürşatİCİN Department of Metallurgical and Materials Engineering Karadeniz Technical UniversityTrabzonTurkey Department of Metallurgical and Materials Engineering Gaziantep UniversityGaziantepTurkey

The aim of this study is to investigate the surface quality of the melt spinning wheel, which was changed from smooth type to textured structure, to atomize liquid metal to form powders. The effects of melt spinning process parameters like wheel speed, gas ejection pressure, molten metal temperature, nozzle–wheel gap and wheel surface quality on the morphological and microstructural features of 6060 aluminum alloy powders and ribbons were investigated. It was observed that ribbon type material was obtained with the smooth wheel and the powder was produced with textured type. The sizes of produced ribbons with smooth surface wheel varied in the range of 30-170 μm in thickness, 4-8 mm in width, and 0.5-1 m in length. The average powder size of the powders manufactured using the textured wheel was in the range of 161-274 μm, depending on the process *** the wheel speed, melt temperature and decreasing gas ejection pressure, nozzle-wheel gap resulted in the decrease of both ribbon thickness and powder size. The microstructures of the powders and ribbons were the equiaxed cellular type, and the average grain sizes diminished with decreasing the ribbon thickness and powder size. The maximum cooling rates were 2.00×10^5 and 1.26×10^4 K/s for the ribbon with thickness of 30 μm and for the powder with size of 87 μm, respectively.

关键词： melt spinning method 6060 aluminum alloy process parameters textured wheel

Dissolution mechanism and kinetics ofβ(Mg_(17)Al_(12))phases in AZ91 magnesium alloy

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Journal of Magnesium and Alloys 2024年第4期12卷 1581-1592页

作者： sultan Alomairy Department of Physics College of ScienceTaif UniversityTaif 21944Saudi Arabia

In this study,the phase transformations,crystallization kinetics and dissolution mechanism ofβphase(Mg_(17)Al_(12))in magnesium alloy AZ91 were investigated by optical microscopy,X-ray diffraction,differential scanning calorimetry and differential *** results indicate that this AZ91 alloy undergoes a phase transformation during aging,a discontinuous precipitation of theβphase(Mg_(17)Al_(12))at 150℃at the grain boundaries and another continuous at 350℃within the *** activation energy of the dissolution reaction of theβphase(Mg_(17)Al_(12))under non-isothermal conditions is 116.781 kJ/mol,while it is 129.7383 kJ/mol under isothermal *** Avrami coefficient,n,relevant for the dissolution kinetics of theβphase(Mg_(17)Al_(12))is 1.152 and 1.211 in the non-isothermal and isothermal conditions *** numerical coefficients m and Avrami n are 0.993 and 1.152.

关键词： AZ91 kinetics β(Mg_(17)Al_(12)) Activation energy Discontinuous precipitation Continuous precipitation DSC

LEGA:A Lightweight and Efficient Group Authentication Protocol for Massive Machine Type Communication in 5G Networks

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Journal of Communications and Information Networks 2020年第4期5卷 457-466页

作者： sultan Basudan Department of Information Technology and Security Jazan UniversitySaudi Arabia

Massive machine type communication(mMTC)is anticipated to be an essential part of fifth generation(5G)*** main challenge for mMTC devices(mMTCDs)is the design of an access authentication scheme that can fulfill the security and privacy requirements of 5G applications,which have specific conditions,including rigorous latency and si-multaneous ***,a novel 5G authentication and key agreement(5G-AKA)protocol was introduced by the 3rd generation partnership project(3GPP)to achieve mMTCD access ***,5G-AKA protocol comes with some security vulnerabilities and significant delay for real-time mMTC applications,particularly when mMTCDs concurrently roam into new *** order to address the real-time secure and efficient access issues of multiple mMTCDs,this paper proposes a lightweight and efficient group authen-tication protocol for mMTC in 5G wireless *** proposed protocol,which integrates bilinear maps and an aggregate certificateless signature mechanism,can achieve several security goals,including avoidance of signaling congestion in the authentication process,mutual authentication,session key agreement,perfect forward/backward secrecy,and masked attack and key escrow *** to existing conventional protocols,the proposed protocol demonstrates robust security and improved performance in terms of signaling cost authentication,bandwidth consumption and compu-tational cost.

关键词： 5G group authentication mMTC roaming privacy security

Sea Turtle Foraging Optimization-Based Controller Placement with Blockchain-Assisted Intrusion Detection in Software-Defined Networks

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Computers, Materials & Continua 2023年第6期75卷 4735-4752页

作者： sultan Alkhliwi Department of Computer Science Faculty of ScienceNorthern Border UniversityArarSaudi Arabia

Software-defined networking(SDN)algorithms are gaining increas-ing interest and are making networks flexible and *** basic idea of SDN is to move the control planes to more than one server’s named controllers and limit the data planes to numerous sending network components,enabling flexible and dynamic network management.A distinctive characteristic of SDN is that it can logically centralize the control plane by utilizing many physical *** deployment of the controller—that is,the controller placement problem(CPP)—becomes a vital model *** the advancements of blockchain technology,data integrity between nodes can be enhanced with no requirement for a trusted third *** the lat-est developments in blockchain technology,this article designs a novel sea turtle foraging optimization algorithm for the controller placement problem(STFOA-CPP)with blockchain-based intrusion detection in an SDN *** major intention of the STFOA-CPP technique is the maximization of lifetime,network connectivity,and load balancing with the minimization of *** addition,the STFOA-CPP technique is based on the sea turtles’food-searching characteristics of tracking the odour path of dimethyl sulphide(DMS)released from food ***,the presented STFOA-CPP technique can adapt with the controller’s count mandated and the shift to controller mapping to variable network ***,the blockchain can inspect the data integrity,determine significantly malicious input,and improve the robust nature of developing a trust relationship between sev-eral nodes in the *** demonstrate the improved performance of the STFOA-CPP algorithm,a wide-ranging experimental analysis was carried *** extensive comparison study highlighted the improved outcomes of the STFOA-CPP technique over other recent approaches.

关键词： Software-defined networking NP hard problem metaheuristics controller placement problem objective function

Arsenic and major cation hydrogeochemistry of the Central Victorian （Australia） surface waters

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Journal of Environmental Sciences 2006年第1期18卷 184-192页

作者： Khawar sultan Kim DOWLING School of Science and Engineering University of Ballarat Mount Helen University Drive Ballarat Victoria 3353 Australia

This paper reports on the major cations（Ca, Mg, Na and K） and arsenic（As） compositions of surface waters collected from major creeks, rivers and lakes in Central Victoria （Australia）. The surface waters were found to be neutral to alkaline （pH 6.7-9.4）, oxidised （average redox potential （Eh） about 130 mV） and showed variable concentrations of dissolved ions （EC, about 51-4386 /μS/cm）. The concen- trations of dissolved major cations in surface waters were found to be in the order of Na〉〉Mg〉Ca〉K and in soils the contents of metals followed an order of abundance as： Ca〉Mg〉〉K〉Na. While Na was the least abundant in soils, it registered the highest dissolved cation in surface waters. Of the four major cations, the average concentration ofNa（98.7 mg/L） was attributed to the weathering of feldspars and atmospheric input. Relatively highly dissolved concentrations of Na and Mg compared with the world average values of rivers reflected the weathering of rock and soil minerals within the catchments. The As soil level is naturally high（linked to lithology） as reflected by high background soil values and mining operations are also considered to be a contributory factor. Under relatively alkaline-oxidative conditions low mobility of dissolved As （average about 7.9 μg/L） was observed in most of the surface waters with a few higher values（〉15 μg/L） around a sewage disposal site and mine railings. Arsenic in soils is slowly released into water under alkaline and/or lower Eh conditions. The efficient sink of Fe, AI and Mn oxides acts as a barrier against the As release under near neutral-oxidising conditions. High As content （average about 28.3 mg/kg） in soils was found to be associated with Fe-hydroxides as revealed by XRD and SEM analysis. The dissolved As concentration was found to be below the recommended maximum levels for recreational water in all surface waters（lakes and rivers） in the study area. Catchment lithology exerted the fundamental control on surface water chemistr

关键词： surface water major cations arsenic soil Australia

In situ infiltration-precipitation processes in some rock systems

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Acta Geochimica 2023年第5期42卷 870-878页

作者： Zahraa Ibrahim Rabih sultan Department of Chemistry American University of BeirutBeirutLebanon

We carry out a chemical treatment(acidization or basification)of typical rock specimens in-situ,and characterize the emerging pattern resulting from the infil-tration-precipitation *** and limestone sam-ples were treated with sulfuric acid,while pyrite was reacted with sodium *** infiltration tech-niques were employed,after selection of the most feasible method for each rock *** patterns of anglesite(PbSO_(4)),anhydrite(CaSO_(4))and goethite(FeOOH)depo-sition presented different alteration modes of the bare rock *** the three deposited minerals,only the anhydrite(CaSO_(4))displayed a band *** formation of a Liesegang pattern in the rock of highest porosity indicates a plausible correlation between the band formation and a minimum porosity requirement.A banded rock of compact texture could then be formed by a cementation mechanism,governing the long time evolution of the rock.

关键词： Liesegang Limestone Galena Pyrite Anglesite Goethite Reaction–diffusion Percolation Porosity Pattern formation

Rare earth elements in tropical surface water,soil and sediments of the Terengganu River Basin,Malaysia

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Journal of Rare Earths 2009年第6期27卷 1072-1078页

作者： Khawar sultan Noor Azhar Shazili Institute of Oceanography University Malaysia TerengganuMengabang Telipot21030 Kuala TerengganuTerengganuMalaysia

The 14 stable rare earth element(REE) concentrations and distribution patterns were investigated for surface waters(n=51),soils(n=52) and sediments(n=42) from the tropical Terengganu River basin,*** chondrite normalized REE patterns of soils developed on four geological units showed enrichment of LREE,a pronounced negative Eu,and depletion of HREE with an enrichment order granite>>metasedimentary>alluvium>*** REE patterns in sediments reflected the soil REE patterns with an ove...

关键词： rare earth elements river/lake water soil sediment Malaysia

Transpalpebral intraocular pressure measurement by Diaton compared to Goldman applanation tonometer in myopic eyes before and after transepithelial photorefractive keratectomy in Saudi Arabia

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International Journal of Ophthalmology(English edition) 2023年第3期16卷 375-381页

作者： sultan Alzuhairy Department of Ophthalmology College of MedicineQassim UniversityBuraidah 51452Saudi Arabia

AIM:To compare intraocular pressure(IOP)measured via the trans palpebral IOP(tp IOP)method using a Diaton or with a Goldman applanation tonometer(GAT)and study the determinants of IOP difference in eyes undergoing transepithelial photorefractive keratectomy(TPrk)for ***:This cross-sectional validation study was held in 2020 in an eye hospital in Saudi *** was measured by Diaton and GAT before treatment,after one week,and one month of *** is considered if IOP difference by Diaton and GAT was less than±2 mm Hg *** IOP difference was tested if correlated to spherical equivalent(SE),central corneal thickness(CCT),age,gender,or tp ***:Totolly 200 myopic eyes of 100 patients were included in the *** mean difference of IOP measured by two methods before TPrk,1wk,and 1mo after TPrk were 0.790,-0.790,and-0.920 mm Hg,respectively(Prk and 82%and 84%at 1wk and 1mo after TPTK,*** week 1,IOP differences were significantly correlated to baseline CCT(P=0.02)and tp IOP at week 1(Prk,only tp IOP was significantly correlated to the difference in IOP(Prk by Diaton and GAT could differ.

关键词： intraocular pressure Goldman applanation tonometry trans palpebral tonometry myopia transepithelial photorefractive keratectomy

Antibacterial and anti-parasitic activities of Terfezia claveryi methanolic extract against some common pathogenic agents of infectious diarrhea

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Asian Pacific Journal of Tropical Biomedicine 2022年第5期12卷 216-222页

作者： sultan F Alnomasy Department of Medical Laboratories Sciences College of Applied Medical SciencesShaqra UniversityAl-Quwayiyah 19257Saudi Arabia

Objective:To assess the antidiarrheal effects of Terfezia claveryi methanolic extract against Escherichia coli,Salmonella typhimurium,Shigella flexneri,and Giardia ***:Antibacterial effects of the Terfezia claveryi methanolic extract were carried out by determining the minimum inhibitory concentration(MIC)and minimum bactericidal concentration through micro broth dilution ***,reactive oxygen species production and protein leakage were *** evaluate the in vitro anti-giardial effects of Terfezia claveryi methanolic extract,Giardia lamblia WB(ATCC®30957)trophozoites were treated with various concentrations of Terfezia claveryi methanolic extract for 10-360 *** addition,the plasma membrane permeability of trophozoites treated with Terfezia claveryi methanolic extract was *** cytotoxicity effects of Terfezia claveryi methanolic extract against normal(HEK293T)and cancer(MCF-7)cells were also assessed using the MTT ***:The MIC and minimum bactericidal concentration of Terfezia claveryi methanolic extract against bacterial strains were in the range of 0.52-1.04 and 1.04-2.08 mg/mL,*** results revealed that reactive oxygen species production and protein leakage were significantly increased after the bacteria were treated with the Terfezia claveryi methanolic extract,especially at 1/3 and 1/2 MICs(P<0.001).Furthermore,Terfezia claveryi methanolic extract decreased the viability of Giardia lamblia trophozoites in a dose-dependent *** claveryi methanolic extract at 1,2,and 4 mg/mL resulted in 100%mortality in Giardia lamblia trophozoites after 360,240,and 120 min,***,Terfezia claveryi methanolic extract altered the permeability of plasma membrane of Giardia lamblia trophozoites by increasing the *** assay revealed that the 50%cytotoxic concentrations values for HEK293T and MCF-7 cells were 4.32 mg/mL and 6.40 mg/mL,respectively,indicating that Terfezia clavery

关键词： Terfezia claveryi Shigellosis Giardiasis Herbal medicines Infectious diarrhea Cellular mechanisms Cytotoxicity Microbiology

DeepGan-Privacy Preserving of HealthCare System Using DL

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Intelligent Automation & Soft Computing 2023年第8期37卷 2199-2212页

作者： sultan Mesfer Aldossary Prince Sattam Bin Abdulaziz University Wadi Ad Dawaser11990Saudi Arabia

The challenge of encrypting sensitive information of a medical image in a healthcare system is still one that requires a high level of computing complexity,despite the ongoing development of *** looking through the previous research,it has become clear that the security issues still need to be looked into further because there is room for expansion in the research ***,neural networks have emerged as a cost-effective and effective optimization strategy in terms of providing security for *** revelation came about as a result of current ***,such an implementation is a technique that is expensive to compute and does not handle the huge variety of different assaults that may be made on *** primary objective of the system that has been described is to provide evidence of a complex framework in which deep neural networks have been applied to improve the efficiency of basic encryption *** research has led to the development and proposal of an enhanced version of methods that have previously been used to encrypt ***,the generative adversarial network(GAN),commonly known as GAN,will serve as the learning network that generates the private *** transformation domain,which reflects the one-of-a-kind fashion of the private key that is to be formed,is also meant to lead the learning network in the process of actually accomplishing the private key creation *** scheme may be utilized to train an excellent Deep Neural Networks(DNN)model while instantaneously maintaining the confidentiality of training medical *** was tested by the proposed approach DeepGAN on open-source medical datasets,and three sets of data:The Ultrasonic Brachial Plexus,the Montgomery County Chest X-ray,and the *** findings indicate that it is successful in maintaining both performance and privacy,and the findings of the assessment and the findings of the security investigation suggest that the de

关键词： Healthcare cryptography deep learning adversarial network privacy