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Isochrone Fitting of Galactic Globular Clusters—Ⅵ.High-latitude Clusters NGC 5024 (m53),NGC 5053,NGC 5272 (m3),NGC 5466,and NGC7099 (m30)

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Research in Astronomy and Astrophysics 2024年第6期24卷 170-190页

作者： G.A.Gontcha.ov s.s.savchenko A.A.marchuk C.J.Bonatto o.s.Ryutina m.Yu.Khovritchev V.B.Il'in A.V.mosenkov D.m.Polia.ov A.A.smirnov Central(Pulkovo)Astronomical observa.ory Russian Academy of SciencesPulkovskoye chaussee 65/1St.Petersburg 196140Russia saint Petersburg state University Universitetskij pr.28St.Petersburg 198504Russia special Astrophysical observa.ory Russian Academy of Sciences369167 Nizhnij ArkhyzRussia Departamento de Astronomia Instituto de FísicaUFRGSAv.Bento Gonçalves9500Porto AlegreRSBrazil saint Petersburg University of Aerospace Instrumentation Bol.Morskaya ul.67ASt.Petersburg 190000Russia Department of Physics and Astronomy Brigham Young UniversityN283 ESCProvoUT 84602USA

We fit various color–magnitude diagrams(CmDs) of the high-latitude Galactic globular clusters NGC 5024(m53),NGC 5053,NGC 5272(m3),NGC 5466,and NGC 7099(m30) by isochrones from the Dartmouth stellar Evolution Database and Bag of stellar Tracks and Isochrones for α–enrichment [α/Fe] = +*** the CmDs,we use data sets from Hubble space Telescope,Gaia,and other sources utilizing,at least,25 photometric filters for each *** obtain the following cha.a.teristics with their statistical uncertainties for NGC 5024,NGC 5053,NGC 5272,NGC 5466,and NGC 7099,respectively:metallicities [Fe/H] =-1.93 ± 0.02,-2.08 ± 0.03,-1.60 ± 0.02,-1.95 ± 0.02,and-2.07 ± 0.04 dex with their systematic uncertainty 0.1 dex;ages 13.00 ± 0.11,12.70 ± 0.11,11.63 ± 0.07,12.15 ± 0.11,and 12.80 ± 0.17 Gyr with their systematic uncertainty 0.8 Gyr;distances(systematic uncertainty added) 18.22 ± 0.06 ± 0.60,16.99 ± 0.06 ± 0.56,10.08 ± 0.04 ± 0.33,15.59 ±0.03 ± 0.51,and 8.29 ± 0.03 ± 0.27 kpc;reddenings E(B-V) = 0.023 ± 0.004,0.017 ± 0.004,0.023 ± 0.004,0.023 ± 0.003,and 0.045 ± 0.002 mag with their systematic uncertainty 0.01 mag;extinctions AV= 0.08 ± 0.01,0.06 ± 0.01,0.08 ± 0.01,0.08 ± 0.01,and 0.16 ± 0.01 mag with their systematic uncertainty 0.03 mag,which suggest the total Galactic extinction AV= 0.08 across the whole Galactic dust to extragalactic objects at the North Galactic *** horizontal branch morphology difference of these clusters is explained by their different metallicity,age,mass-loss efficiency,and loss of low-mass members in the evolution of the core-collapse cluster NGC 7099 and loose clusters NGC 5053 and NGC 5466.

关键词： (stars:)Hertzsprung Russell and C-m diagrams (Ism:)dust extinction (Galaxy:)globular clusters:general (Galaxy:)globular clusters:individual(NGC 5024,NGC 5053,NGC 5272,NGC 5466,NGC7099)

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： C.Y.morassuti A.P.L silva L.a.o.Nunes s.m.Lima L.H.C.Andrade optical and Photothermal spectroscopy Group(GEoF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Rena.o Archer Information Technology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of são Carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher a.ounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value a.ong the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio optical thermometry Judd-ofelt Rare earths

Natural Convection of a Power-Law Na.ofluid in a square Cavity with a Vertical Fin

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Fluid Dynamics & materials Processing 2024年第9期20卷 2091-2108页

作者： Amira m’hadbi mohammed El Ganaoui haïkel Ben hamed Amenallah Guizani Khalid Chtaibi LERmAB Department of Transition and Energy Efficiency ProfessionsIUT H Poincaréde LongwyUniversity of LorraineLongwy54400France LPT Center for Energy Research and Technologies(Borj Cedria2084)University of Tunis El ManarTunis1068Tunisia LTI Department of Mechanical Engineering and ProductionIUTUniversity of Picardie Jules-VerneAmiens80025France

The behavior of non-Newtonian power-law na.ofluids under free convection heat transfer conditions in a cooled square enclosure equipped with a heated fin is investigated *** particular,the impact of na.ofluids,composed of water and Al_(2)o_(3),Tio_(2),and Cu na.oparticles,on heat transfer enhancement is *** aim of this research is also to analyze the influence of different parameters,including the Rayleigh number(Ra=10^(4)-10^(6)),na.oparticle volume fraction(φ=0%-20%),non-Newtonian power-law indexes(n=0.6-1.4),and fin dimensions(Ar=0.3,0.5,and 0.7).streamlines and isotherms are used to depict flow and related heat transfer *** indicate that thermal performance improves with increasing Rayleigh number,regardless of the na.oparticle type or na.ofluid rheological *** suggests that the buoyancy force has a significant impact on heat transfer,particularly near the heat *** Nusselt number is more sensitive to variations in Cu na.oparticle volume fractions compared to Al₂o₃and Tio₂.moreover,the average Nusselt numbers for power-law na.ofluids with n1)are greater(smaller)than for Newtonian fluids due to the decrease(increase)in viscosity with increasing(decreasing)shear rate,at the same values of Rayleigh number Ra.owing to the amplification(attenuation)of the convective ***,the most substantial enhancement is observed with Cu-water shear-thinning na.ofluid,where the Nusselt number increases by 136%when changing from Newtonian to shear thinning behavior and by 154.9%when adding 16%na.oparticle volume ***,an even larger increase of 57%in the average Nusselt number is obtained on increasing the fin length from 0.3 to 0.7.

关键词： Heat transfer na.ofluid non-Newtonian fluid natural convection

Engineering of efficient visible light photocatalysts:Ti_(1-x+y)Cu_(x)La_(y)o_(2)(x=0.03;y=0,0.005,0.01) compositions

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Journal of Rare Earths 2024年第3期42卷 497-505,I0003页

作者： s.m.Ya.out A.m.Youssef Inorganic Chemistry Department National Research Centre(NRC)El Buhouth StDokkiCairo12622Egypt

In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as a.orting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of para.ount *** the current study, we report the photocatalytic cha.a.teristics of four compositions composed of Tio_(2),Ti_(0.97)Cu_(0.03)o_(2), Ti_(0.965)Cu_(0.03)La_(0.005)o_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)o_(2)powders for two harmful dyes(Congo red and methylene blue). The X-ray diffraction technique verified the configuration of mixed anatase and rutile phases in pure Tio_(2)and Ti_(0.97)Cu_(0.03)o_(2)powders while Ti_(0.965)Cu_(0.03)La_(0.005)o_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)o_(2)powders possess anatase phase only. The changes of the band gap structure and dimensions of the unit cell volume of Tio_(2)confirm the substitution of Ti^(4+)sites by Cu^(2+)and La^(3+)ions. Remarkable widening of wavelengths absorption with formation of long absorption tails were found in Tio_(2)(3.13 e V) through insertion of La^(3+)plus Cu^(2+)ions. Ti_(0.965)Cu_(0.03)La_(0.005)o_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)o_(2)samples exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on sEm images, incorporation of Cu^(2+)and La^(3+)ions influences the surface morphology of Tio_(2). The resulting Ti_(0.97)Cu_(0.03)o_(2), Ti_(0.965)Cu_(0.03)La_(0.005)o_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)o_(2)powders present enhanced photocatalytic activity towards Congo red dye degradation compared to pure one under natural solar spectrum. The best Ti_(0.96)Cu_(0.03)La_(0.01)o_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm CR dye in 20 min as well as a.ove average photocatalytic efficiency of 63% for 30 ppm CR dye in 120 min. As well, it showed acceptable photodegradation activity of 52% for 30 ppm mB solution in 140 min of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)Cu_(0.03)La_(0.01)o_(2)catalyst can be clarified in terms of higher ch

关键词： semiconductor Tio_(2) Rare earths Congo red methylene blue solar spectrum Photodegradation

Influence of cerium ions on structure-dependent magnetic properties of Ba-sr m-type hexaferrite na.ocrystals

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Journal of Rare Earths 2024年第2期42卷 364-372,I0005页

作者： Ram A.Pawar sunil m.Patange P.m.Dighe sher singh meena Abdullah GAl-sehemi mehboobali Pannipara santosh s.Jadhav Department of Physics ArtsCommerce and Science CollegeAhmednagar413711MaharashtraIndia Department of Physics Shri Krishna MahavidyalayaGunjotiDistOsmanabad413606MaharashtraIndia Padmashri Vikhe Patil College of Arts Science and CommercePravaranagarA/P.Loni(Kd)Tal.RahataDistAhmednagar413713MaharashtraIndia solid state Physics Division Bhabha Atomic Research CentreMumbai400085MaharashtraIndia Department of Chemistry King Khalid UniversityAbha61413Saudi Arabia Department of Physics D.S.M's ArtsCommerce and Science CollegeJintur431509MaharashtraIndia

The present study is a systematic effort to investigate the structure-sensitive magnetic parameters of Ce^(3+) substituted Ba-sr hexaferrite na.ocrystals chemically formulated as Ba_(0.5)sr_(0.5)Ce_(x)Fe_(12-x)o_(19) where x=0.0-0.2 with Δx=*** hexaferrite powders were prepared using the sol-gel self-ignition route and structurally cha.a.terized by means of powder X-ray diffraction and Fourier transform infrared *** creation of the m-type hexaferrite phase within the synthesized samples was revealed from the Rietveld refinement of the X-ray *** occurrence of a secondary phase of Ceo_(2) was revealed within the hexaferrites for the substitution,x> *** refined X-ray diffraction data were utilized to compute the lattice parameters,X-ray density,and lattice parameter *** crystal structure plotted from the refined XRD data reveals the occupancy of the ions at different lattice *** XPs data.of the hexaferrite were analyzed to confirm the oxidation states of the constituent *** na.ocrystalline nature of the hexaferrites was revealed from the crystallite sizes calculated using scherer's *** analysis of FTIR spectra confirms that only a fraction of Ce^(3+)accommodated in the lattice and the remaining Ce content reside in the form of the Ceo_(2) *** morphology of the hexaferrites was analyzed from the FEsEm profiles of the ferrite *** magnetic behavior study was performed by analyzing the Curie temperature,hysteresis loops,and hyperfine interactions by means of susceptibility,V.s.m,and mossbauer spectroscopy,*** hexaferrites with increasing coercivity,decreasing saturation magnetization,and decreasing Curie temperature are reported in the *** substituted Ce^(3+)ions inhibit the grain growth and create lattice imperfections giving rise to hexaferrites with tuned magnetic parameters suitable for different applications.

关键词： Ba-sr hexaferrite Ce^(3+)substitution XPs saturation magnetization Coercivity m?ssbauer spectroscopy

Nonlinear study on the mechanical Performance of Built-Up Cold-Formed steel Concrete-Filled Columns under Compression

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Computer modeling in Engineering & sciences 2024年第6期139卷 3435-3465页

作者： oulfa harrat Yazid hadidane s.m.Anas Nadhim ha.a. sor Ahmed Fa.ouk Deifalla Paul o.a.oyera Nadia Gouider Civil Engineering La.ora.ory Faculty of TechnologyDepartment of Civil EngineeringBadji Mokhtar-Annaba UniversityP.O.Box 12Annaba23000Algeria Department of Civil Engineering Faculty of Engineering and TechnologyJamia Millia Islamia(A Central University)New Delhi110025India Civil Engineering Department University of GarmianKalar46021Iraq Department of Civil Engineering Harran UniversitySanliurfa63510Turkey structural Engineering and Construction management Department Future University in EgyptNew Cairo11835Egypt Department of Civil Engineering Covenant UniversityOta112233Nigeria

Given their numerous functional and architectural benefits,such as improved bearing capacity and increased resistance to elastic instability modes,cold-formed steel(CFs)built-up sections have become increasingly developed and used in recent years,particularly in the construction *** paper presents an analytical and numerical study of assembled CFs two single channel-shaped columns with different slenderness and configurations(backto-back,face-to-face,and box).These columns were joined by double-row rivets for the back-to-back and box configurations,whereas they were welded together for the face-to-face *** built-up columns were filled with ordinary concrete of good *** element models were applied,using ABAQUs software,to assess mechanical performance and study the influence of assembly techniques on the behavior of cold-formed columns under axial *** approaches based on Eurocode 3 and Eurocode 4 recommendations for un-filled and concrete-filled columns respectively were followed for the numerical analysis,and concrete confinement effects were also considered per American Concrete Institute(ACI)standards for face-to-face and box *** obtained results indicated a good correlation between the numerical results and the proposed analytical methodology which did not exceed 8%.The failure modes showed that the columns failed due to instabilities such as local and global buckling.

关键词： Cold-formed steel built-up sections slenderness rivets welded axial compression analytical approaches confinement buckling

A pipeline to cha.a.terize p53 effectors by integrative cistrome and transcriptome analysis in a genetically-defined orga.oid model

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Genes & Diseases 2024年第2期11卷 512-515页

作者： June-ha shin Hwa-Ryeon Kim Jae-seok Roe Department of Biochemistry College of Life Science and BiotechnologyYonsei UniversitySeoul 120-749Republic of Korea

Tumor-protein 53(p53)is a transcription factor(TF)encoded by TP53(Trp53 in mice)and is a master regula.or of tumor-suppressive programs'.Importantly,TP53 is the most frequently mutated gene in human cancer,and its loss of function contributes to tumor development,exemplified by variable p53 mutations detected in 50%-75%of pancreatic cancers.2 From these perceptions,a number of targets transcribed by p53 that confer tumor suppression have been ***,our understanding of how p53 prevents normal cells from initiating tumorigenesis is still *** complement this limitation,herein,we established a new approach to identify underlying effectors transcribed by p53 in normal physiology.

关键词： incomplete initiating herein

Fast prediction of rain erosion in wind turbine blades using a data-based computational tool

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Journal of Hydrodynamics 2024年第3期36卷 504-518页

作者： Juan m.Gimenez sergio R.Idelsohn Eugenio oñate Centre Internacional de mètodes Numèrics en Enginyeria(CImNE) Edifici C1 Campus Nord UPC C/Gran CapitàS/NBarcelonaSpain

Wind turbines(WTs)face a high risk of failure due to environmental factors like erosion,particularly in high-precipitation areas and offshore *** this paper we introduce a novel computational tool for the fast prediction of rain erosion damage on WT blades that is useful in operation and maintenance decision making *** approach is as follows:Pseudo-Direct Numerical simulation(P-DNs)simulations of the droplet-laden flow a.ound the blade section profile are employed to build a high-fidelity data set of impact statistics for potential operating *** this database as training data,a machine learning-based surrogate model provides the feature of the impact pattern over the 2-D section for given wind and rain *** this information,a fatigue-based model estimates the remaining lifetime and erosion damage for both homogeneous and coating-substrate blade *** prediction is done by quantifying the accumulated droplet impact energy and evaluating operative conditions over time periods for which the weather at the installation site is *** this work,we describe the modules that compose the prediction method,namely the database creation,the training of the surrogate model and their coupling to build the prediction ***,the method is applied to predict the remaining lifetime and erosion damage to the blade sections of a reference *** evaluate the reliability of the tool,several site locations(offshore,coastal,and inland),the coating material and the coating thickness of the blade are *** few minutes we are able to estimate erosion after many years of *** results are in good agreement with field observations,showing the promise of the new rain erosion prediction approach.

关键词： Wind turbine blades leading edge erosion fatigue Pseudo-Direct Numerical simulation(P-DNs) machine learning eblader

Development and testing of a high-power s-band klystron at BINP sB RAs

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Nuclear science and Techniques 2024年第7期35卷 58-67页

作者： A.Levichev A.Barnya.ov s.sa.oylov D.Nikiforov V.Iva.ov m.Arsentyeva D.Chekmenev o.Pavlov I.Pivova.ov Budker Institute of Nuclear Physics Lavrentyeva Av.11NovosibirskRussia630090 Novosibirsk state University Pirogova Str.2NovosibirskRussia630090

This paper details the development and testing of the first working prototype of the s-band high-power klystron,accomplished at the Budker Institute of Nuclear Physics,siberian Branch,Russian Academy of sciences(BINP sB RAs).Upon testing,the klystron demonstrated the following parameters:an operating frequency of 2856 mHz and a peak power output of 50 *** paper presents the klystron's design,its constituent units,and pertinent processing procedures,a.ong with discussions on the measurement of its parameters.

关键词： Klystron Linear accelera.or Electron beam