检索结果-南通市图书馆

Analysis of the Impact of the Blazhko Effect Both on the Van Hoof Effect and Radial Velocity Amplitude in the Star RR Lyr

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第6期24卷 253-272页

作者： Y.el jariri f.L.Sefyani A.Benhida Z.Benkhaldoun K.Kolenberg K.Chafouai A.Habib m.Sabil Observatoire de l'Ouka.m.den LPHEAFSSMUniversitéCadi AyyadMarrakech2390Morocco Observatoire de l'Ouka.m.den LPHEAFSTGUniversitéCadi AyyadMarrakech549Morocco département de physique Universitéd'Anvers Avenue Groenenborger 171Anvers2020Belgium LICPm ENSA-BMUniversitéSultan Moulay SlimaneBeni-Mellal23020Morocco

The Van Hoof effect is a phase shift existing between the radial velocity curves of hydrogen and metallic lines within the atmosphere of pulsating *** this article,we present a study of this phenomenon through the spectra of the brightest pulsating star RR Lyr of RR Lyrae stars recorded for 22 *** based ourselves,on the one hand,on 1268 spectra(41 nights of observation)recorded between the years 1994 and 1997 at the Observatory of Haute Provence(OHP,france)previously observed by Chadid and Gillet,and on the other hand on 1569 spectra(46nights of observation)recorded at our Ouka.m.den Observatory(morocco)between 2015 and *** this study,we have detected information on atmospheric dynamics that had not previously been ***,the Van Hoof effect which results in a clear correlation between the radial velocities of hydrogen and those of the metallic lines has been observed and analyzed at different Blazhko phases.A correlation between the radial velocities of different metallic lines located in the lower atmosphere has been observed as *** the first time,we were able to show that the amplitude of the radial velocity curves deduced from the lines of hydrogen and that of feⅡ(λ4923.921?)increases toward the minimum of the Blazhko cycle and decreases toward the maximum of the same Blazhko ***,we found that the Van Hoof effect is also modulated by the Blazhko ***,toward the minimum of the Blazhko cycle the Van Hoof effect is more visible and at the maximum of the Blazhko cycle,this effect is *** also observed the temporal evolution of the amplitudes of the radial velocities of the lower and upper *** observed over a long time,we can interpret it as a function of the Blazhko phases.

关键词： stars:atmospheres stars:variables:RR Lyrae shock waves techniques:spectroscopic techniques:radial velocities stars:individual(RR Lyr)

Surface morphology and cell viability of samarium(Ⅲ) oxide/chromium(Ⅲ) oxide/graphene oxide/polycaprolactone targeting wound dressing

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第3期42卷 555-561,I0005页

作者： muteb H.Alshammari a.m.d Onayzan Alshammari mohamed Tharwat elabbasy Rafat Zreiq faris moha.m.d Albati m.A.el-morsy A.A.menazea department of Health Informatics College of Public Health and Health InformaticsUniversity of Ha'ilHa'ilSaudi Arabia department of Surgery College of MedicineUniversity of Ha'ilHa'ilSaudi Arabia department of Public Health College of Public Health and HealthInformaticsHalUniversityHa'il2440Saudi Arabi food Control department Faculty of Veterinary MedicineZagazig UniversityZagazig44519Egypt Applied Science Research Center Applied Science Private UniversityAmman541350Jordan College of Shariah and Law Ha'il UniversityHa'il2440Saudi Arabia College of Science and Humanities in Al-Kharj Physics DepartmentPlasma Technology and Material Science UnitPrince Sattam Bin Abdulaziz UniversityAl-kharj11942Saudi Arabia Physics department Faculty of ScienceUniversity of DamittaNew Damietta34517.Egyp Spectroscopy department Physics Research InstituteNational Research CentreDokki12622GizaEgypt

Combinations of metal and lanthanide oxides have been done through casted films for potential medical applications. In this regard, samarium(Ⅲ) oxide/chromium(Ⅲ) oxide/graphene oxide(GO)/polycaprolactone(PCL) based films nano-composites(NCs) were fabricated, pointing their utilization as a biological scaffold for wound dressing purposes. Also, samarium(Ⅲ) oxide and chromium(Ⅲ) oxide have been merged as promising optical constituents due to their unique optical behavior. The structural and compositional examination of the studied NCs was executed by X-ray diffraction(XRd), Raman, and f.eld emission scanning electron microscopy(fESEm). The Sm_(2)O_(3)/Cr_(2)O_(3)/GO/PCL NC exhibits a surface with a lower roughness degree owing to the presence of GO. Cr_(2)O_(3)shows size reduction upon GO insertion to reach 1.2 μm as the average grain size, whilst Sm_(2)O_(3)records an average grain size of less than 1 μm. As well, the polymeric nano-compositions exhibit variation in contact angle values that hit 29.76°± 3.52°for Sm_(2)O_(3)/PCL, and 48.62°± 1.37°for Sm_(2)O_(3)/Cr_(2)O_(3)/GO/PCL as the second lowest contact angle. The optical behavior contributes to absorption edge relocation along the x-axis from 1.7 eV for pure PCL, to 2.65 eV for Sm_(2)O_(3)/Cr_(2)O_(3)/GO/PCL. Regarding biological responses, the cell exposed to 2.5 μg/m L of Sm_(2)O_(3)/Cr_(2)O_(3)/GO/PCL shows cell viability of 119.31%, while 5 μg/m L hits 99.6%. Additionally, the resulting cell attachment micrographs show layers of fibroblast tissue, besides the proliferation and growth of cultivated cells. Thus, the Sm_(2)O_(3)/Cr_(2)O_(3)/GO/PCL scaffold provides 3d proliferation of fibroblast cells endorsing the wound healing process.

关键词： Wound healing Wound dressing Polycaprolactone Sm_(2)O_(3) Cr_(2)O_(3) Rare earths

design of a Novel Exoskeleton with Passive magnetic Spring Self-locking and Spine Lateral Balancing

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2024年第1期21卷 236-255页

作者： Jhon f.Rodríguez-León Betsy d.m.Chaparro-Rico daniele Cafolla francesco Lago Eduardo Castillo-Castañeda Giuseppe Carbone Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada Unidad Querétaro MecatronicaInstituto Politécnico NacionalCerro Blanco 14176090 Colinas del CimatarioQuerétaroMexico department of mechanical Energy and Management EngineeringUniversity of CalabriaVia P.Bucci Cubo 46 C87036 RendeItaly faculty of Science and Engineering Department of Computer ScienceSwansea UniversitySwanseaUK CESTER University of Cluj-NapocaCluj-NapocaRomania

This paper proposes a new upper-limb exoskeleton to reduce worker physical *** proposed design is based on a novel PRRRP(P-Prismatic;R-Revolute)kinematic chain with 5 passive degrees of freedom(dof).Utilizing a magnetic spring,the proposed mechanism includes a specially designed locking mechanism that maintains any desired task *** proposed exoskeleton incorporates a balancing mechanism to alleviate discomfort and spinal torsional effects also helping in limb weight *** paper reports specific models and simulations to demonstrate the feasibility and effectiveness of the proposed *** experimental characterization is performed to validate the performance of the mechanism in terms of forces and physical strain during a specific application consisting of ceiling-surface drilling *** obtained results preliminarily validate the engineering feasibility and effectiveness of the proposed exoskeleton in the intended operation task thereby requiring the user to exert significantly less force than when not wearing it.

关键词： Assistive mechanism Exoskeleton Locking mechanism Bionic robot

Nickel sulfate solution fluoride separation with hydrous zirconium oxide

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Tungsten 2024年第2期6卷 367-381页

作者： elbert m.Nigri Ummul K.Sultana André L.A.Santos James W.Vaughan Sonia d.f.Rocha department of mining Engineering Federal University of Minas GeraisBelo Horizonte 31270-901Brazil School of Chemical Engineering University of QueenslandSt Lucia 4072Australia

fluoride is an impurity in nickel sulfate production,which is required for electric vehicle *** zirconium oxide(HZO)was evaluated for removing fl uoride from nickel sulfate *** fluoride removal occurred at pH value 4 and optimal pH value is 4–5,considering Zr *** availability decreases with pH due to hydrogen fluoride and zirconium fluoride aqueous *** removal is initially rapid,with 50 wt.%removal in 7 min,followed by slow removal up to 68 wt.%after 72 h and follows second order rate *** removal was dominated by an ion exchange mechanism and resulting Zr–f bonds were observed using fourier-transform infrared *** presence of nickel sulfate decreased loading capacity compared to a salt-free *** maintained adsorption capacity through five cycles of loading and regeneration.

关键词： Hydrous zirconium oxide Nickel sulfate fluoride Adsorption Anion exchange

Comparative analysis of microstructure,mechanical,and corrosion properties of biodegradable mg-3Y alloy prepared by selective laser melting and spark plasma sintering

在线全文

学校读者我要写书评

暂无评论

Journal of magnesium and Alloys 2024年第4期12卷 1496-1510页

作者： P.minárik m.Zemková S.Šašek J.dittrich m.Knapek f.Lukáˇc d.Koutný J.Jaroš R.Král faculty of mathematics and Physics Charles UniversityKe Karlovu 5Praha 12116Czech Republic Research Centre University ofŽilinaUniverzitná8215/1Žilina 01026Slovakia Institute of Plasma Physics of the Czech Academy of Sciences Za Slovankou 1782/318200 Praha 8Czech Republic Institute of machine and Industrial design Brno University of TechnologyTechnická2896/2Brno 61669Czech Republic

This work explored possibilities of biodegradable magnesium alloy mg-3Y preparation by two modern powder metallurgy techniques–spark plasma sintering(SPS)and selective laser melting(SLm).The powder material was consolidated by both methods utilising optimised parameters,which led to very low porosity(∼0.3%)in the SLm material and unmeasurably low porosity in the SPS *** main aim of the study was the thorough microstructure characterisation and interrelation between the microstructure and the functional properties,such as mechanical strength,deformability,and corrosion *** materials showed comparable strength of∼110 mPa in tension and compression and relatively good deformability of∼9%and∼21%for the SLm and SPS materials,*** corrosion resistance of the SPS material in 0.1 m NaCl solution was superior to the SLm one and comparable to the conventional extruded *** digital image correlation during loading and the cross-section analysis of the corrosion layers revealed that the residual porosity and large strained grains have the dominant negative effect on the functional properties of the SLm *** the other hand,one of the primary outcomes of this study is that the SPS consolidation method is very effective in the preparation of the W3 biodegradable alloy,resulting in material with convenient mechanical and degradation properties that might find practical applications.

关键词： magnesium Yttrium Powder metallurgy microstructure mechanical strength Corrosion resistance

Smart prediction of liquefaction-induced lateral spreading

在线全文

学校读者我要写书评

暂无评论

Journal of Rock mechanics and Geotechnical Engineering 2024年第6期16卷 2310-2325页

作者： muha.m.d Nouman Amjad Raja Tarek Abdoun Waleed el-Sekelly New York University(NYU)Abu dhabi Abu Dhabi129188United Arab Emirates University of management and Technology Lahore54372Pakistan department of Civil and Environmental Eng. Rensselaer Polytechnic Institute(RPI)1108th StreetJEC 4049TroyNY12180USA department of Structural Engineering Mansoura UniversityMansoura35516Egypt

The prediction of liquefaction-induced lateral spreading/displacement(dh)is a challenging task for civil/geotechnical *** this study,a new approach is proposed to predict dh using gene expression programming(GEP).Based on statistical reasoning,individual models were developed for two topographies:free-face and gently sloping *** with a comparison with conventional approaches for predicting the dh,four additional regression-based soft computing models,*** process regression(GPR),relevance vector machine(RVm),sequential minimal optimization regression(SmOR),and m5-tree,were developed and compared with the GEP *** results indicate that the GEP models predict dh with less bias,as evidenced by the root mean square error(RmSE)and mean absolute error(mAE)for training(i.e.1.092 and 0.815;and 0.643 and 0.526)and for testing(i.e.0.89 and 0.705;and 0.773 and 0.573)in free-face and gently sloping ground topographies,*** overall performance for the free-face topology was ranked as follows:GEP>RVm>m5-tree>GPR>SmOR,with a total score of 40,32,24,15,and 10,*** the gently sloping condition,the performance was ranked as follows:GEP>RVm>GPR>m5-tree>SmOR with a total score of 40,32,21,19,and 8,***,the results of the sensitivity analysis showed that for both free-face and gently sloping ground,the liquefiable layer thickness(T_(15))was the major parameter with percentage deterioration(%d)value of 99.15 and 90.72,respectively.

关键词： Lateral spreading Intelligent modeling Gene expression programming(GEP) Closed-form solution feature importance

Immunoglobulin A glomerulonephropathy:A review

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2024年第8期12卷 1388-1394页

作者： mohamad el Labban Salim Surani department of Internal medicine Mayo Cliic Health SystemMankatoMN 56001United States department of medicine&Pharmacology Texas A&M UniversityCollege StationTX 77843United State

In this editorial,we comment on the article by meng et al published in the World Journal of Clinical *** comprehensively review immunoglobulin A nephro-pathy(IgAN),including epidemiology,clinical presentation,diagnosis,and ***,also known as Berger's disease,is the most frequent type of primary glomerulonephritis(GN)*** is mostly found among the Asian *** presentation can be variable,from microscopic hematuria to a rapidly progressive *** 50%of patients present with single or recurring episodes of gross *** upper respiratory infection and tonsillitis often precede these *** 30%of patients present microscopic hematuria with or without proteinuria,usually detected on routine *** diagnosis relies on having a renal biopsy for pathology and immunofluorescence *** focus on risk stratification and management of *** provide a review of all the landmark studies to *** to the 2021 KdIGO(kidney disease:Improving Global Outcomes)guidelines,patients with non-variant form IgAN are first treated conservatively for three to six *** approach consists of adequate blood pressure control,reduction of proteinuria with renin-angiotensin system blockade,treatment of dyslipidemia,and lifestyle modifications(weight loss,exercise,smoking cessation,and dietary sodium restrictions).following three to six months of conservative therapy,patients are further classified as high or low risk for disease ***-risk patients have proteinuria≥1 g/d ord with significant microscopic hematuria and active inflammation on kidney *** experts consider proteinuria≥2 g/d to be very high *** with high and very high-risk profiles are treated with immunosuppressive therapy.A proteinuria level ofd and stable/im-proved renal function indicates a good treatment response for patients on immu-nosuppressive therapy.

关键词： Immunoglobulin A nephropathy Glomerulonephritis Nephritic syndrome Angiotensin-converting enzyme inhibitor Angiotensin receptor blocker Systemic steroids mycophenolate mofetil

miniSCIdOm: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High Power Laser Science and Engineering 2024年第2期12卷 41-50页

作者： A.Corvino m.Reimold E.Beyreuther f.-E.Brack f.Kroll J.Pawelke J.d.Schilz m.Schneider U.Schramm m.E.P.Umlandt K.Zeil T.Ziegler J.metzkes-Ng Helmholtz-Zentrum dresden–Rossendorf DresdenGermany Technische Universität dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:Universitätsklinikum freiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research f.elds such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIdOm detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

Numerical calculation of Z-scan measurements for nonlinear media with large phase shift

在线全文

学校读者我要写书评

暂无评论

Optoelectronics Letters 2024年第3期20卷 177-182页

作者： m.d.Zidan A.Allahham department of Physics Atomic Energy Commission of SyriaP.O.Box 6091DamascusSyria

We have reported the characteristics of a Z-scan for the poly(azaneylylidene-acylene)(dAZA) polymer, as nonlinear medium with a large nonlinear phase shift using continuous-wave(CW) laser beam. It has been verified that the fresnel diffraction model is applicable for analyses of Z-scan measurements with dAZA polymer at high laser power. It was found that Z-scan curves with peak-to-valley features appear as the applied light intensity increases in the case of a large nonlinear phase shift. The Z-scan experiments were carried out using a CW laser to verify the theoretical calculations in the case of a large nonlinear phase shift model. Our results show good agreements between the experimental data and the proposed theoretical models.

关键词： nonlinear phase media