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Theoretical & Applied mechanics Letters 2023年第4期13卷 272-279页

作者： hamad m.hasan Saad S.Alkhfaji Sattar A.mutlag Department of mechanical Engineering University of AnbarRamadi 31001Iraq Department of medical Instrumentation Engineering Ashur University CollegeBaghdad 10044Iraq

Buckling and postbuckling characteristics of laminated graphene-enhanced composite(GEC)truncated conical shells exposed to torsion under temperature conditions using finite element method(FEm)simulation are presented in this *** the thickness direction,the GEC layers of the conical shell are ordered in a piece-wise arrangement of functionally graded(FG)distribution,with each layer containing a variable volume fraction for graphene *** calculate the properties of temperaturedependent material of GEC layers,the extended Halpin-Tsai micromechanical framework is *** FEm model is verified via comparing the current results obtained with the theoretical estimates for homogeneous,laminated cylindrical,and conical shells,the FEm model is *** computational results show that a piece-wise FG graphene volume fraction distribution can improve the torque of critical buckling and torsional postbuckling ***,the geometric parameters have a critical impact on the stability of the conical ***,a temperature rise can reduce the crucial torsional buckling torque as well as the GEC laminated truncated conical shell’s postbuckling strength.

关键词： Torsional postbuckling Graphene enhanced composite Functionally graded graphene Finite element method Conical shell

Influence of erbium on structural,and charged particles,photons,and neutrons shielding properties of Ba_(1-x)Er_(x)SnO_(3) perovskite ceramics

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Journal of Rare Earths 2024年第4期42卷 724-732页

作者： m.K.h.hamad Nidal Dwaikat m.H.A.mhareb m.I.Sayyed R.m.hamad Y.S.m.Alajerami m.A.Almessiere Gameel Saleh Ahmad Hussein Alomari K.A.Ziq Department of Basic Sciences School of Social and Basics SciencesAl Hussein Technical UniversityKing Abdullah II St 242Amman11831Jordan Department of Physics College of Engineering and PhysicsInterdisciplinary Research Center for Advanced MaterialsKing Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia Basic and Applied Scientific Research Center Imam Abdulrahman Bin Faisal UniversityP0.Box 1982Dammam31441Saudi Arabia Department of Physics Faculty of ScienceIsra UniversityAmman11622Jordan Department of Nuclear medicine Research Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Arabia medical Imaging Department Applied Medical Sciences FacultyAl Azhar University-Gaza CityPo.Box 1277Palestine Department of Biophysics Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box1982Dammam 31441Saudi Arabia Department of Biomedical Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Energy&minerals Regulatory Commission Amman11821Jordan

Five perovskite ceramics samples of Ba_(1-x)Er_(x)SnO_(3) with x=0.00,0.05,0.10,0.15,and 0.20 were synthesized using the conventional solid-state reaction *** prepared samples were characterized by X-ray diffraction(XRD),Fourier transforms infrared(FTIR),and UV-Vis *** shielding properties against ionizing radiation were also *** XRD analysis shows the perovskite cubic structure as the major phase in all *** FTIR reveals a distinctive band around 614-620 cm^(-1) ascribed to the antisymmetric O-Sn-O ***-Vis spectroscopy was used to determine the bandgap according to diffuse reflectance,and the results display a fixed enhancement in the bandgap from 3.2 to 3.3 eV for all ***-ray shielding properties of the synthesized samples were experimentally measured and compared with XCOm computational *** relative differences(Δ,%)between experimental and theo retical values are low and fall within the 0.446%-7.10%*** addition of Er leads to the enhanced density,neutron,and gamma shielding *** contrast,charged particles’shielding parameters gradually reduce with rising Er *** results suggest that Ba_(1-x)Er_(x)SnO_(3) samples can be used in different radiation shielding applications.

关键词： Perovskite Ceramics Gamma ray shielding mass stopping power Rare earths

Theory for Charge Density Wave and Orbital-Flux State in Antiferromagnetic Kagome metal FeGe

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Chinese Physics Letters 2024年第4期41卷 90-104页

作者：马海洋殷嘉鑫 m.Zahid hasan 刘健鹏 School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China ShanghaiTech Laboratory for Topological Physics ShanghaiTech UniversityShanghai 201210China Quantum Science Center of Guangdong-HongKong-macao Greater Bay Area Shenzhen 518045China Laboratory for Topological Quantum matter and Advanced Spectroscopy(B7) Department of PhysicsPrinceton UniversityPrincetonNew Jersey 08544USA Princeton Institute for Science and Technology of materials Princeton UniversityPrincetonNew Jersey 08544USA materials Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCalifornia 94720USA Liaoning Academy of materials Shenyang 110167China

We theoretically study the charge order and orbital magnetic properties of a new type of antiferromagnetic kagome metal *** on first-principles density functional theory calculations,we study the electronic structures,Fermi-surface quantum fluctuations,as well as phonon properties of the antiferromagnetic kagome metal *** is found that charge density wave emerges in such a system due to a subtle cooperation between electron-electron interactions and electron–phonon couplings,which gives rise to an unusual scenario of interaction-triggered phonon instabilities,and eventually yields a charge density wave(CDW)*** further show that,in the CDW phase,the ground-state current density distribution exhibits an intriguing star-of-David pattern,leading to flux density *** orbital fluxes(or current loops)in this system emerge as a result of the subtle interplay between magnetism,lattice geometries,charge order,and spin-orbit coupling(SOC),which can be described by a simple,yet universal,tight-binding theory including a Kane-mele-type SOC term and a magnetic exchange *** further study the origin of the peculiar step-edge states in FeGe,which sheds light on the topological properties and correlation effects in this new type of kagome antiferromagnetic material.

关键词： interaction phonon orbital

Biosynthesized CS-mgO/zeolite hybrid material:An efficient adsorbent for chlorpyrifos removal-Kinetic studies and response surface methodology

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Emerging Contaminants 2024年第3期10卷 304-317页

作者： mohammed T.m.H.hamad Belal N.A.mahran Central Laboratory for Environmental Quality monitoring National Water Research CenterEgypt

The prevalence of organophosphate pesticides in aquatic environments raises severe concerns on a global ***,an insecticide,is included in a class of organophosphate *** is widely used on agricultural lands to control pests in cotton,fruit,and *** acute toxicity of chlorpyrifos is still dangerous to all aquatic living *** the treatment of water contaminated with chlorpyrifos is an important *** recent decade has witnessed adsorption technology emerging as an advanced organophosphate pesticide wastewater treatment with great potential and a grand blueprint,in which the specific surface area and active sites of the adsorbent are considered to be the two most important characteristics largely impacting the adsorption *** this study,a CS-mgO/Zeolite composite was prepared by the microbial method as an effective adsorbent for the removal of chlorpyrifos from an aqueous *** adsorbent's properties were carefully characterized using Xray diffraction,scanning electron microscopy,and Fourier-transform infrared *** refinement of experimental conditions,encompassing variations in adsorbent dosage,contact time,and chlorpyrifos concentration at five discrete levels,was systematically undertaken through the utilization of a composite central design rooted in response surface *** solution pH played a key role in chlorpyrifos removal,and a pH of 7.0 was selected according to its high adsorption *** highest removal(80.9%)of chlorpyrifos by CS-mgO/Zeolite was obtained at an optimum pH of 7,a contact time of 40 min,an adsorbent dosage of 0.4 g/L,and a chlorpyrifos concentration of 5 mg/L^(-1).The adsorption results were highly fitted with the Freundlich adsorption isotherm model,and the maximum adsorption was 83.3 mg/*** studies indicate that the removal of chlorpyrifos followed the pseudo-secondorder model of adsorption(0.994).The thermodynamic parameters indicate the sponta

关键词： Chlorpyrifos adsorption CS-mgO/Zeolite Response surface methodology

Tuning structural,electrical,dielectric and magnetic properties of mg-Cu-Co ferrites via dysprosium(Dy^(3+))doping

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Journal of Rare Earths 2024年第1期42卷 137-146,I0005页

作者： maria Akhtar m.S.hasan Nasir Amin N.A.morley muhammad Imran Arshad Department of Physics Government College UniversityFaisalabad38000Pakistan Department of Physics The University of Lahore53700Pakistan Department of materials Science and Engineering The University of SheffieldS13JDUK Department of Physics&Astronomy University College LondonUK

In current research work,Dy3+substituted mg0.5Cu0.25Co0.25Fe2-xDyxO4(0.0≤x≤0.04 with the step interval of 0.01)soft ferrites were synthesized by the sol-gel auto combustion *** prepared samples were characterized by the techniques using X-ray diffraction(XRD),scanning electron microscopy(SEm),energy dispersive X-ray spectroscopy(EDS),Fourier transform infrared(FTIR)spectroscopy,curre nt-voltage(Ⅰ-Ⅴ)measurement,LCR meter,vibrating sample magnetometer(VSm)and *** data reveal that the average crystallite size is 49.71 nm and the lattice constant is 0.83703 nm for sample x=*** non-uniform grain growth was demonstrated by micrographs and impurity-free elemental composition was observed from EDX *** DC resistivity has an increasing and decreasing trend in ferromagnetic and paramagnetic regions with an increase in ***,the high resistivity is observed with the order of 1010Ω·cm,and the activation energy is 0.944 eV for samples x=*** dielectric parameters including dielectric constant,dielectric losses,and impedance gradually decrease with the increase in frequency from 8 Hz to 8 *** minimum dielectric loss at high frequency is found for sample x=*** coercivity(Hc)and saturation magnetization(ms)are found in the ranges of 520.82-544.02 Oe and 20.5841-21.1473 emu/g,*** observations confirm that dysprosium(x=0.03)doped mCC-soft ferrites may be applicable in transformer cores,microwave absorbance,and telecommunication devices.

关键词： Soft ferrites DC resistivity Dielectric loss Impedance Coercivity Rare earths

Superior rectus/levator complex in acquired anophthalmic socket repaired with spheric implant—a computed tomography scan and topographic study

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1483-1488页

作者： Shaikha Al Eid hamad m AlSulaiman Sahar m Elkhamary Osama Al Sheikh Alicia Ferrero-Galindo Rajiv Kandekhar Silvana A Schellini Oculoplastic Division King Khaled Eye Specialist HospitalRiyadh 11462Saudi Arabia Radiology Division King Khaled Eye Specialist HospitalRiyadh 11462Saudi Arabia Department of Diagnostic Radiology Mansoura Faculty of MedicineMansoura 35511Egypt University Hospital Rio Hortega Valladolid 47012Spain Research Department King Khaled Eye Specialist HospitalRiyadh 11462Saudi Arabia Ophthalmology Department Medical SchoolState University of Sao PauloBotucatu 18618-687Brazil

AIm:To determine whether the levator palpebrae superioris(LPS)/superior rectus(SR)muscle complex,can influence the position of the upper lid and fornix in acquired anophthalmic ***:This comparative non-randomized and non-interventional study included retrospective data of 21 patients with unilateral acquired anophthalmic sockets repaired with spheric ***-resolution computed tomography(CT)measurements of the LPm/SR muscle complex and clinical topographic position of the upper lid,superior and inferior fornix depth in primary gaze position were *** data were presented as frequency and percentage proportions and quantitative variables comparing the socket measurements with the normal contralateral orbit was statistically analyzed using non-parametric tests considering Pmic orbits had a significantly shorter LPS length(P=0.01)and significantly thicker SR(P=0.02)than the normal *** was present in anophthalmic sockets but not in normal orbits(P=0.002),while levator function was normal in both(P>0.05,all comparisons).The superior fornix depth was similar in the anophthalmic socket and the contralateral normal orbit(P=0.192)as well the inferior fornix depth(P=0.351).CONCLUSION:Acquired anophthalmic sockets repaired with spheric implants have shorter LPS,thicker SR,and more lagophthalmos than normal *** relationship of the LPS and SR with other orbital structures,associated with passive or active forces acting in the final position of the lids and external ocular prosthesis should be further investigated.

关键词： anophthalmic socket spheric implant levator palpebrae superioris superior rectus lagophthalmos fornix depth

multi-objective performance optimization&thermodynamic analysis of solar powered supercritical CO_(2)power cycles using machine learning methods&genetic algorithm

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Energy and AI 2024年第1期15卷 193-216页

作者： Asif Iqbal Turja md mahmudul hasan m.monjurul Ehsan Yasin Khan Department of mechanical and Production Engineering(mPE) Islamic University of Technology(IUT)Board BazarGazipur1704Bangladesh

The present study is focused on multi-objective performance optimization&thermodynamic analysis from the perspectives of energy and exergy for Recompression,Partial Cooling&main Compression Intercooling supercritical CO_(2)(sCO_(2))Brayton cycles for concentrated solar power(CSP)applications using machine learning *** novelty of this work lies in the integration of artificial neural networks(ANN)and genetic algorithms(GA)for optimizing the performance of advanced sCO_(2)power cycles considering climatic variation,which has significant implications for both the scientific community and engineering applications in the renewable energy *** methodology employed includes thermodynamic analysis based on energy,exergy&environmental factors including system performance *** system is modelled for net power production of 15 mW thermal output utilizing equations for the energy and exergy balance for each ***,thermodynamic model extracted dataset used for prediction&evaluation of Random Forest,XGBoost,KNN,AdaBoost,ANN and LightGBm ***,considering climate conditions,multi-objective optimization is carried out for the CSP integrated sCO_(2)Power cycle for optimal power output,exergy destruction,thermal and exergetic *** algorithm and TOPSIS(technique for order of preference by similarity to ideal solution),multi-objective decision-making tool,were used to determine the optimum operating *** major findings of this work reveal significant improvements in the performance of the advanced sCO_(2)cycle by 1.68%and 7.87%compared to conventional recompression and partial cooling cycle,*** research could advance renewable energy technologies,particularly concentrated solar power,by improving power cycle designs to increase system efficiency and economic *** advanced supercritical CO_(2)power cycles in concentrated solar power plants might increase renewable energy use

关键词： Supercritical CO_(2) Concentrated solar power Thermodynamic analysis machine learning Artificial neural network multi-objective optimization

Pediatric and adult liver transplantation in Bahrain: The experiences in a country with no available liver transplant facilities

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World Journal of Transplantation 2024年第1期14卷 96-111页

作者： hasan m Isa Fatema A Alkharsi Jawad K Khamis Sawsan A hasan Zainab A Naser Zainab N mohamed Afaf m mohamed Shaikha A Altamimi Department of Pediatrics Salmaniya Medical ComplexManama 26671Bahrain Department of Pediatrics Arabian Gulf UniversityManama 26671Bahrain Department of medicine Salmaniya Medical ComplexManama 26671Bahrain Public Health Directorate Ministry of HealthManama 26671Bahrain The Overseas Office Supreme Committee for Treatment AbroadMinistry of HealthManama 26671Bahrain

BACKGROUND Liver transplantation(LT)is a life-saving procedure for patients with end-stage liver disease and has become the standard and most effective treatment method for these *** are many indications for LT that vary between countries and *** outcome of LT depends on the available facilities and surgical expertise,as well as the types of liver graft donors *** To assess the clinical characteristics of patients from Bahrain who underwent LT overseas,and analyze factors affecting their *** In this retrospective cohort study,we reviewed the medical records and overseas committee registry information of all pediatric and adult patients who were sent overseas to undergo LT by the Pediatric and medical Departments of Salmaniya medical Complex and Bahrain Defence Force Hospital via the Overseas Treatment Office,ministry of Health,Kingdom of Bahrain,between 1997 and *** data,LT indication,donor-recipient relationship,overseas LT center,graft type,post-LT medications,and LT complications,were *** measured included the overall and 5-year LT survival ***’s exact,Pearsonχ2,and mann-Whitney U tests were used to compare the pediatric and the adults’group in terms of clinical characteristics,donor-recipient relationship,medication,complications,and *** analysis was estimated via the Kaplan-meier’s *** and multivariate analyses were used to detect predictors of *** Of the 208 eligible patients,170(81.7%)were sent overseas to undergo LT while 38(18.3%)remained on the waiting *** the 170 patients,167(80.3%)underwent LT and were included in the *** majority of the patients were Bahraini(91.0%),and most were males(57.5%).One-hundred-and-twenty(71.8%)were adults and 47(28.3%)were *** median age at transplant was 50.0[interquartile range(IQR):14.9–58.4]*** main indication for pediatric LT was biliary atresia(31.9%),while that of adult LT was

关键词： Overseas liver transplantation End-stage liver disease Liver transplant facilities Liver donor Biliary atresia Hepatitis C

Fever assessment in children under five: Are we following the guidelines?

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World Journal of Clinical Pediatrics 2024年第1期13卷 62-72页

作者： hasan m Isa Ahmed J Isa murtadha A Alnasheet mahmood m mansoor Department of Pediatrics Salmaniya Medical ComplexManama 26671Bahrain Department of Pediatrics Arabian Gulf UniversityManama 26671Bahrain Department of General Surgery Salmaniya Medical ComplexManama 26671Bahrain

BACKGROUND Fever is a common cause of medical consultation and hospital admission,particularly among ***,the United Kingdom’s National Institute for Health and Care Excellence(NICE)updated its guidelines for assessing fever in children under five years of *** efficient assessment and management of children with fever are crucial for improving patient *** To evaluate fever assessment in hospitalized children and to assess its adherence with the NICE Fever in under 5s *** We conducted a retrospective cohort review of the electronic medical records of children under five years of age at the Department of Pediatrics,Salmaniya medical Complex,Bahrain,between June and July *** data,vital signs during the first 48 h of admission,route of temperature measurement,and indications for admission were *** was defined according to the NICE *** children were divided into five groups according to their age(0-3 months,>3-6 months,>6-12 months,>12-36 months,and>36-60 months).Patients with and without fever were compared in terms of demography,indication for admission,route of temperature measurement,and other vital *** with the NICE Fever in the under 5s guideline was *** compliance was defined as>95%,partial compliance as 70%-95%,and minimal compliance as≤69%.Pearson’sχ^(2),Student’s t test,the mann-Whitney U test,and Spearman’s correlation coefficient(rs)were used for *** Of the 136 patients reviewed,80(58.8%)were *** median age at admission was 14.2[interquartile range(IQR):1.7-44.4]months,with the most common age group being 36-60 ***-six(26.4%)patients had fever,and 100(73.6%)were *** commonest age group for febrile patients(>12-36 months)was older than the commonest age group for afebrile patients(0-3 months)(P=0.027).The median weight was 8.3(IQR:4.0-13.3)*** with fever had higher weight than those without fever[10.2(IQR:7.3-13.0)vs 7

关键词： Fever Pediatrics Admission patterns Temperature measurement Guidelines Bahrain

Randomization Strategies in Image Steganography Techniques:A Review

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Computers, materials & Continua 2024年第8期80卷 3139-3171页

作者： AFm Zainul Abadin Rossilawati Sulaiman mohammad Kamrul hasan Center for Cyber Security Faculty of Information Science and TechnologyUniversiti Kebangsaan Malaysia(UKM)BangiSelangor43600Malaysia Department of Information and Communication Engineering Pabna University of Science and TechnologyPabna6600Bangladesh

Image steganography is one of the prominent technologies in data hiding *** system performance mostly depends on the embedding *** goal is to embed strictly confidential information into images without causing perceptible changes in the original *** randomization strategies in data embedding techniques may utilize random domains,pixels,or region-of-interest for concealing secrets into a cover image,preventing information from being discovered by an *** implementation of an appropriate embedding technique can achieve a fair balance between embedding capability and stego image imperceptibility,but it is challenging.A systematic approach is used with a standard methodology to carry out this *** review concentrates on the critical examination of several embedding strategies,incorporating experimental results with state-of-the-art methods emphasizing the robustness,security,payload capacity,and visual quality metrics of the stego *** fundamental ideas of steganography are presented in this work,along with a unique viewpoint that sets it apart from previous works by highlighting research gaps,important problems,and ***,it offers a discussion of suggested directions for future study to advance and investigate uncharted territory in image steganography.

关键词： Information hiding image steganography randomized embedding techniques payload capacity imperceptibility