检索结果-南通市图书馆

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

在线全文

学校读者我要写书评

暂无评论

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

在线全文

学校读者我要写书评

暂无评论

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

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

在线全文

学校读者我要写书评

暂无评论

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

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

在线全文

学校读者我要写书评

暂无评论

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

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

Randomization Strategies in Image Steganography Techniques:A Review

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

A Review and Bibliometric Analysis of the Current Studies for the 6G Networks

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer modeling in Engineering & Sciences 2024年第9期140卷 2165-2206页

作者： Qusay m.Salih md.Arafatur Rahman Ahmad Firdaus mohammed Rajih Jassim.hasan Kahtan Jasni mohamad Zain Ahmed Hussein Ali Faculty of Computing Universiti Malaysia Pahang Al-Sultan Abdullah(UMPSA)PekanPahang26600Malaysia Department of medical Equipment Technology Engineering Al Salam University CollegeBaghdadIraq School of mathematics and Computer Science University of WolverhamptonWolverhampton01902UK Department of Production Engineering and metallurgy University of TechnologyBaghdadIraq Cardiff School of Technologies Cardiff Metropolitan UniversityCardiffCF52YBUK Institute for Big Data Analytics and Artificial Intelligence(IBDAAI) Kompleks Al-KhawarizmiUniversiti Teknologi MARAShah AlamSelangor40450Malaysia Department Computer Science Al-Salam University CollegeBaghdadIraq

The race to develop the next generation of wireless networks,known as Sixth Generation(6G)wireless,which will be operational in 2030,has already *** realize its full potential over the next decade,6G will undoubtedly necessitate additional improvements that integrate existing solutions with cutting-edge ***,the studies about 6G are mainly limited and scattered,whereas no bibliometric study covers the 6G ***,this study aims to review,examine,and summarize existing studies and research activities in *** study has examined the Scopus database through a bibliometric analysis of more than 1,000 papers published between 2017 and ***,we applied the bibliometric analysis methods by including(1)document type,(2)subject area,(3)author,and(4)country of *** study’s results reflect the research 6G community’s trends,highlight important research challenges,and elucidate potential directions for future research in this interesting area.

关键词： 6G bibliometric wireless networks review

Smart tailoring of molecular catalysts:mounting approach to oxygen reduction reaction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of materials Science & Technology 2024年第1期168卷 169-184页

作者： Anuj Kumar mohd Ubaidullah Guoxin Zhang Jasvinder Kaur Saira Ajmal mudassir hasan Krishna Kumar Yadav Hafiz m.Adeel Sharif Ram K.Gupta Ghulam Yasin Nano-Technology Research Laboratory Department of ChemistryGLA UniversityMathuraUttar Pradesh 281406India Department of Chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia Department of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdaoShandong 266590China Institute for Advanced Study Shenzhen UniversityShenzhenGuangdong 518060China Department of Chemistry Kansas Polymer Research CenterPittsburg State UniversityPittsburgKS 66762United States Faculty of Science and Technology Madhyanchal Professional UniversityRatibadBhopal 462044India Environmental and Atmospheric Sciences Research Group Scientific Research CenterAl-Ayen UniversityThi-QarNasiriyah 64001Iraq Department of Chemical Engineering King Khalid University Saudi Arabia Department of Chemistry School of SciencesIFTM UniversityMoradabadUttar Pradesh 244102India Research Center for Eco-Environmental Engineering Dongguan University of TechnologyDongguan 523808China School of Environment and Civil Engineering Dongguan University of TechnologyDongguanGuangdong 523808China

Efficient electrocatalytic rupture of energy-rich molecules(H_(2)and O_(2))is a green approach for gener-ating clean energy for modern *** this context,porphyry-type molecular electrocatalysts act intelligently toward oxygen reduction reaction(ORR),a fundamental process in fuel cells,due to their redox-rich chemistry,which involves core metal ions and macrocyclic *** concerned scientific community has tried many times to correlate the ORR intermediates with their formation kinetics and simplify the associated multi H+/e-stages during the ORR process,constructing several volcano plots be-tween catalytic Tafel data,turnover frequencies,and overpotentials for many *** the fact that many review articles on molecular electrocatalysts for ORR have been published,understanding the strategic implications and molecular catalyst intelligence towards homogenous ORR has been poorly *** review examined the relationships between volcano plots of current *** parameters and the Sabatier principle in order to explain the intelligence of molecular electrocatalysts and approaches for their creation,as well as the difficulties and potential prospects of molecular *** facts distinguish this review from previously published articles and will pique the scien-tific community’s interest in avoiding trial-and-error procedures for catalyst creation while also allowing for more exact evaluations of the molecular catalyst’s performance.

关键词： Electrocatalysis molecular catalysts Oxygen reduction reaction Sabatier principle

Does the Redshift Distribution of Swift Long GRBs Trace the Star-Formation Rate?

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Astronomy and Astrophysics 2024年第1期14卷 20-44页

作者： Ali m. hasan Walid J. Azzam Department of Physics College of Science University of Bahrain Sakhir Bahrain

Gamma-ray bursts (GRBs) are extremely powerful explosions that have been traditionally classified into two categories: long bursts (LGRBs) with an observed duration T90 > 2 s, and short bursts (SGRBs) with an observed duration T90 T90 is the time interval during which 90% of the fluence is detected. LGRBs are believed to emanate from the core-collapse of massive stars, while SGRBs are believed to result from the merging of two compact objects, like two neutron stars. Because LGRBs are produced by the violent death of massive stars, we expect that their redshift distribution should trace the star-formation rate (SFR). The purpose of our study is to investigate the extent to which the redshift distribution of LGRBs follows and reflects the SFR. We use a sample of 370 LGRBs taken from the Swift catalog, and we investigate different models for the LGRB redshift distribution. We also carry out monte Carlo simulations to check the consistency of our results. Our results indicate that the SFR can describe the LGRB redshift distribution well for high redshift bursts, but it needs an evolution term to fit the distribution well at low redshift.

关键词： Gamma-Ray Bursts Redshift Distribution Star-Formation Rate