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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

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Vaccination effect on a stochastic epidemic model with healing and relapse

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International Journal of Biomathematics 2024年第1期17卷 29-59页

作者： m.m.Abdeslami L.Basri m.El Fatini I.Sekkak r.Taki Laboratory of Partial Differential Equations Spectral Algebra and Geometry Department of mathematics Faculty of Sciences Ibn Tofail UniversityBP 133KénitraMorocco Centre de recherche en Sante Publique montréal(Québec)H3N 1X9 Canada Departement de Medecine Sociale et Preventive Ecole de SantéPublique de I'Universitéde Montreal 101Avenue du ParcMontréal(Quebec)H3N 1X9Canada EST Sidi Bennour Chouaib Doukkali UniversityEl JadidaMorocco

In this work,we consider a stochastic epidemic model with vaccination,healing and *** prove the existence and the uniqueness of the positive *** establish sufficient conditions for the extinction and the persistence in mean of the stochastic ***,we also establish sufficient conditions for the existence of ergodic stationary distribution to the model,which reveals that the infectious disease will *** graphical illustrations of the approximate solutions of the stochastic epidemic model have been performed.

关键词： Stochastic epidemic model with relapse and healing vaccination extinction persistence in mean markov semigroup stationary distribution

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Kaoline-based catalyst for a high stability desulfurization of sour heavy naphtha in a three-phase oscillatory baffled reactor

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Particuology 2024年第1期84卷 249-260页

作者： Hassan m.Hmood Saba A.Gheni Safaa m.r.Ahmed mudheher m.Ali Hamid Yonis Saleh mohammed H.mohammed Awad E.mohammed marwan A.mahomood Hiba r.mohammed Ahmed A.Hassan Adam Harvey North refineries Company Ministry of OilIraq Chemical Engineering Department Tikrit UniversityIraq ministry of Oil Iraq AL-Hawija Technical Institute Northern Technical UniversityMoselIraq School of Engineering Newcastle UniversityUK

To meet the rapidly increasing demand for energy and the dramatic depletion of conventional crude oil,it is imperative to utilize sour *** no coke being produced,oxidative desulfurization(ODS)of naphtha lowers its sulfur content and average molecular *** this article,we outline a method for heavy naphtha non-extractive ODS using a very stable *** technique involves the use of a solid catalyst with oxygen gas as the *** necessitated relatively high mixing intensities;hence a three-phase Oscillatory Baffled reactor(OBr)was *** catalyst was based on the zeolite ZSm-5,prepared from natural kaolin by a series of delamination and activation steps and impregnated with Fe.A TiO2 nanolayer was applied,using the sol-gel method,to prevent rapid *** reactor performance was evaluated to minimize the sulfur content in the naphtha *** to the protective coating,the sulfur conversion stabilized at 90%.The results of this work establish the use of natural clay-based catalysts in a continuous,three-phase ODS,particularly with regard to proving long-term *** also showed that modest ODS can be achieved using an environmentally friendly oxidant,at mild operating conditions,whilst maintaining stability.

关键词： Natural kaoline Desulfurization Three-phase Oscillatory baffled reactor

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Beyond dentistry:could prevention and screening for neurodegenerative diseases start in the dental office?

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Neural regeneration research 2024年第1期19卷 156-157页

作者： Francesca r.Buccellato Daniela Galimberti Gianluca m.Tartaglia Department of Biomedical Surgical and Dental SciencesUniversity of MilanMilanItalyFondazione IRCCS Ca’GrandaOspedale Maggiore PoliclinicoMilanItaly

The differential diagnosis of neurodegenerative diseases is complex and relies on clinical assessment,biomarker levels in cerebrospinal fluid,neuroimaging and neuropsychological *** efforts of the scientific community are focused on two aspects:a)the discovery of minimally invasive biomarkers;b)the discovery of early biomarkers that can predict the progression to clinical disease in the presymptomatic stage of a *** the impact of the number of patients affected by chronic neurodegenerative diseases on public health expenditures,early diagnosis seems to be a primary need of our society.

关键词： diagnosis diseases prevention

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Generation of polarized electron beams through self-injection in the interaction of a laser with a pre-polarized plasma

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High Power Laser Science and Engineering 2024年第3期12卷 62-68页

作者： L.r.Yin X.F.Li Y.J.Gu N.Cao Q.Kong m.Büscher S.m.Weng m.Chen Z.m.Sheng Key Laboratory of Nuclear Physics and Ion-beam Application(moE) Institute of Modern PhysicsDepartment of Nuclear Science and TechnologyFudan UniversityShanghaiChina State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina SANKEN(Institute of Scientific and Industrial research) Osaka UniversityOsakaJapan Sichuan research Institute Shanghai Jiao Tong UniversityChengduChina Peter Grünberg Institut(PGI-6) Forschungszentrum JülichJülichGermany Institut für Laser-und Plasmaphysik Heinrich-Heine-Universität DüsseldorfDüsseldorfGermany Key Laboratory for Laser Plasmas(moE) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghaiChina Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghaiChina

Polarized electron beam production via laser wakefield acceleration in pre-polarized plasma is investigated by particlein-cell *** evolution of the electron beam polarization is studied based on the Thomas±Bargmann±michel±Telegdi equation for the transverse and longitudinal self-injection,and the depolarization process is found to be influenced by the injection *** the case of transverse self-injection,as found typically in the bubble regime,the spin precession of the accelerated electrons is mainly influenced by the ***,in the case of longitudinal injection in the quasi-1D regime(for example,*** et al.,***.110,135002(2013)),the direction of electron spin oscillates in the laser *** the electrons move around the laser axis,the net influence of the laser field is nearly zero and the contribution of the wakefield can be ***,an ultra-short electron beam with polarization of 99%can be obtained using longitudinal self-injection.

关键词： laser wakefield acceleration longitudinal self-injection particle-in-cell simulation polarized electron beam

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Freeze-thaw cycles and associated geomorphology in a post-glacial environment:current glacial,paraglacial,periglacial and proglacial scenarios at Pico de Orizaba volcano,mexico

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Journal of mountain Science 2024年第6期21卷 1954-1977页

作者： Víctor SOTO Carlos m.WELSH r. Kenji YOSHIKAWA Hugo DELGADO GrANADOS Centro de Ciencias de la Tierra Universidad VeracruzanaCircuito Gonzalo Aguirre BeltránS/NZona Universitaria91090XalapaMéxico Water and Environmental research Center University of Alaska FairbanksFairbanksAlaska 99775USA Instituto de Geofísica Universidad Nacional Autónoma de MéxicoCiudad de México 04150México Department of Earth and Environmental Sciences Ludwig Maximilians UniversitätMunich 80333Germany

The glacial history of Pico de Orizaba indicates that during the Last Glacial maximum,its icecap covered up to~3000 m asl;due to the air temperature increasing,its main glacier has retreated to 5050 m *** retraction of the glacier has left behind an intense climatic instability that causes a high frequency of freeze-thaw cycles of great intensity;the resulting geomorphological processes are represented by the fragmentation of the bedrock that occupies the upper parts of the *** is a notable lack of studies regarding the fragmentation and erosion occurring in tropical high mountains,and the associated geomorphological risks;for this reason,as a first stage of future continuous research,this study analyzes the freezing and thawing cycles that occur above 4000 m asl,through continuous monitoring of surface ground *** results allow us to identify and characterize four zones:glacial,paraglacial,periglacial and *** was found that the paraglacial zone presents an intense drop of temperature,of up to~9℃ in only sixty *** rock fatigue and intense freeze-thaw cycles that occur in this area are responsible for the high rate of rock disintegration and represent the main factor of the constant slope dynamics that occur at the *** activity decreases,both in frequency and intensity,according to the distance to the glacier,which is where the temperature presents a certain degree of stability,until reaching the proglacial zone,where cycles are almost non-existent,and therefore there is no gelifraction *** geomorphological processes have resulted in significant alterations to the mountain slopes,which can have severe consequences in terms of risk and water.

关键词： Freeze-Thaw Gelifraction mountain mechanical erosion Periglacial geomorphology Postglacial scenarios

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Cannabinoids and endocannabinoids as therapeutics for nervous system disorders:preclinical models and clinical studies

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Neural regeneration research 2024年第4期19卷 788-799页

作者： r.Scott Duncan Sean m.riordan matthew C.Gernon Peter Koulen Department of Ophthalmology School of MedicineUniversity of Missouri Department of Biomedical Sciences School of MedicineUniversity of Missouri

Cannabinoids are lipophilic substances derived from Cannabis sativa that can exert a variety of effects in the human *** have been studied in cellular and animal models as well as in human clinical trials for their therapeutic benefits in several human *** of these include central nervous system(CNS)diseases and dysfunctions such as forms of epilepsy,multiple sclerosis,Parkinson’s disease,pain and neuropsychiatric *** addition,the endogenously produced cannabinoid lipids,endocannabinoids,are critical for normal CNS function,and if controlled or modified,may represent an additional therapeutic avenue for CNS *** review discusses in vitro cellular,ex vivo tissue and in vivo animal model studies on cannabinoids and their utility as therapeutics in multiple CNS *** addition,the review provides an overview on the use of cannabinoids in human clinical trials for a variety of CNS *** and endocannabinoids hold promise for use as disease modifiers and therapeutic agents for the prevention or treatment of neurodegenerative diseases and neurological disorders.

关键词： anandamide cannabidiol cannabinoid endocannabinoid epilepsy multiple sclerosis neurodegeneration neuroprotection tetrahydrocannabinol

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Prediction of the undrained shear strength of remolded soil with non-linear regression,fuzzy logic,and artificial neural network

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Journal of mountain Science 2024年第9期21卷 3108-3122页

作者： YÜNKÜL Kaan KArAÇOr Fatih GÜrBÜZ Ayhan BUDAK TahsinÖmür Department of Civil Engineering Faculty of Engineering and ArchitectureTokat Gaziosmanpaşa UniversityTokat 60100Türkiye Department of Civil Engineering Faculty of Engineering and ArchitectureKafkas UniversityKars 36000Türkiye Department of Civil Engineering Faculty of EngineeringGazi UniversityAnkara 06570Türkiye ministry of Youth and Sports Ankara 06090Türkiye

This study aims to predict the undrained shear strength of remolded soil samples using non-linear regression analyses,fuzzy logic,and artificial neural network modeling.A total of 1306 undrained shear strength results from 230 different remolded soil test settings reported in 21 publications were collected,utilizing six different measurement *** water content,plastic limit,and liquid limit were used as input parameters for fuzzy logic and artificial neural network modeling,liquidity index or water content ratio was considered as an input parameter for non-linear regression *** non-linear regression analyses,12 different regression equations were derived for the prediction of undrained shear strength of remolded ***-Forward backpropagation and the TANSIG transfer function were used for artificial neural network modeling,while the mamdani inference system was preferred with trapezoidal and triangular membership functions for fuzzy logic *** experimental results of 914 tests were used for training of the artificial neural network models,196 for validation and 196 for *** was observed that the accuracy of the artificial neural network and fuzzy logic modeling was higher than that of the non-linear regression ***,a simple and reliable regression equation was proposed for assessments of undrained shear strength values with higher coefficients of determination.

关键词： Undrained shear strength Liquidity index Water content ratio Non-linear regression Artificial neural networks Fuzzy logic

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Systematic radio Telescope Alignment Using Portable Fringe Projection Profilometry

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Nanomanufacturing and metrology 2024年第1期7卷 75-85页

作者： Joel Berkson Justin Hyatt Nathan Julicher Byeongjoon Jeong Isaac Pimienta rachel Ball Wyatt Ellis Jason Voris Diego Torres‑Barajas Daewook Kim James C.Wyant College of Optical Sciences University of Arizona1630 E.University Blvd.TucsonAZ 85721USA Department of Astronomy at Steward Observatory University of Arizona933 N Cherry Ave.TucsonAZ 85721USA

In 2019,the Event Horizon Telescope(EHT)released the first-ever image of a black hole event *** are now aiming for higher angular resolutions of distant targets,like black holes,to understand more about the fundamental laws of gravity that govern our *** achieve this higher resolution and increased sensitivity,larger radio telescopes are needed to operate at higher frequencies and in larger *** like the next-generation Very Large Array(ngVLA)and the Square-Kilometer Array(SKA)require building hundreds of telescopes with diameters greater than 10 ms over the next *** has a twofold *** telescope surfaces need to be more accurate to operate at higher frequencies,and the logistics involved in maintaining a radio telescope need to be simplified to support them properly in large *** of these problems can be solved with improved methods for surface metrology that are faster and more accurate with a higher *** leads to faster and more accurate panel alignment and,therefore,a more productive *** this paper,we present the use of binocular fringe projection profilometry as a solution to this problem and demonstrate it by aligning two panels on a 3-m radio telescope *** measurement takes only 10 min and directly delivers feedback on the tip,tilt,and piston of each panel to create the ideal reflector shape.

关键词： metrology Fringe projection profilometry Off-axis alignment radio astronomy radio antenna

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Effect of solidification cooling rate on microstructure and tribology characteristics of Zn-4Si alloy

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International Journal of minerals,metallurgy and materials 2024年第2期31卷 362-373页

作者： F.Akbari m.Golkaram S.Beyrami G.Shirazi K.mantashloo r.Taghiabadi m.Saghafi Yazdi I.Ansarian Department of metallurgy and material Science Imam Khomeini International University(IKIU)Qazvin ***Iran

The main objective of this work was to modify the microstructure and enhance the tribological properties of a new Zn-4Si al-loy through a high solidification cooling rate(SCr).According to the results,by increasing the SCr from 2.0 to 59.5℃/s the average size of primary Si particles and that of the grains reduced from 76.1 and 3780μm to less than about 14.6 and 460μm,***-ing the SCr also enhanced the microstructural homogeneity,decreased the porosity content(by 50%),and increased the matrix hardness(by 36%).These microstructural changes enhanced the tribological *** instance,under the applied pressure of 0.5 mPa,an in-crease in the SCr from 2.0 to 59.5℃/s decreased the wear rate and the average friction coefficient of the alloy by 57%and 23%,*** wear mechanism was also changed from the severe delamination,adhesion,and abrasion in the slowly-cooled alloy to the mild tribolayer delamination/abrasion in the high-cooling-rate-solidified sample.

关键词： zinc-silicon alloy primary silicon solidification cooling rate tribology sliding wear

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