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Zircon chemistry and new laser ablation U–Pb ages for uraniferous granitoids in SW Cameroon

Acta Geochimica 2020年第1期39卷 43-66页

作者： v.f.embui C.E.Suh J.M.Cottle J.Etame J.Mendes C.M.Agyingi A.vishiti E.M.Shemang B.Lehmann Department of Geology University of BueaP.O.Box 63BueaSouth West RegionCameroon Ore Treatment Laboratory Institute of Geological and Mining Research(IRGM)P.O.Box 4110YaoundeNlongkakCameroon Department of Geology Mining and Environmental ScienceUniversity of BamendaP.O.Box 39BambiliCameroon Department of Earth Sciences and Earth Research Institute Webb Hall 2028University of CaliforniaSanta BarbaraCA 93106-9630USA Laboratory of Geosciences Natural resources and Environment Department of Earth SciencesFaculty of ScienceUniversity of DoualaP.O.Box 24157DoualaCameroon Department of Civil Engineering University Institute of TechnologyUniversity of DoualaP.O.Box 8698DoualaCameroon Departamento de Geologia IGEOUniversidade Federal do Rio de JaneiroCidade UniversitariaRio de Janeiro 21910-949Brazil Department of Earth and Environmental Sciences Botswana International University of Science and TechnologyPrivate Bag 16PalapyeBotswana Mineral Resources Technical University of ClausthalClausihal-ZellerfeldGermany

The Ekomedion two-mica granite,southwestern Cameroon,has potential for uranium and molybdenum ***,we present LA-ICP-MS U-Pb ages,Lu-Hf isotope characteristics,trace element concentrations and Ti-geothermometry of zircon from this granite hosting U-Mo mineralization in pegmatitic *** majority of zircon are CL-dark though some CL-bright cores were also identified.U-Pb zircon age data range from 121±3 to743±11 Ma with only 5 of 34 ages being near *** concordant mean age of 603±12 Ma is similar to ages of granitic intrusions along the Central African Shear Zone in *** ages with mean of261±6 Ma reveal open system behavior with respect to Pb and/or *** e Hfi values range from-20.3 *** implies that U-Mo was remobilized during partial melting of the surrounding *** Th/U>0.1 as well as an increasing Hf with decreasing Th/U indicates that fractional crystallization was the main factor that controlled U-Mo mineralization in pegmatitic pods.Y and Y/Ho ratios cluster from 29 to 33 close to the chondritic ratio of 28 and indicate fractionation of Y and Ho with low f contents during the earliest stages of *** stage accumulation of f-rich magmatic-hydrothermal fluids impacted U-Mo mineralization as a *** contains a prominent negative Eu anomaly pointing to a fractionating system rich in *** Ti-in-zircon temperatures span 672℃to1232℃with the temperatures at the high end reflecting interference from mineral inclusions in the zircon grains while the lower temperature values are linked to crystallization.

关键词： Zircons Uranium-molybdenum Cameroon

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具有BCC或fCC晶体结构的固溶体高熵合金设计

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材料工程 2024年第1期52卷 16-26页

作者： HORBAN v.f. 乌克兰国家科学院弗兰采维奇材料问题研究所乌克兰基辅03680

高熵合金最初报道于21世纪初期,该类合金具有较高的混合熵值,使其具有优异的热稳定性;较大的晶格畸变,产生了强烈固溶强化效果;较大的负焓值导致在晶粒内部形成团簇结构,有效阻碍了位错运动,进一步提高了合金强度。高熵合金独有的这些特... 详细信息

高熵合金最初报道于21世纪初期,该类合金具有较高的混合熵值,使其具有优异的热稳定性;较大的晶格畸变,产生了强烈固溶强化效果;较大的负焓值导致在晶粒内部形成团簇结构,有效阻碍了位错运动,进一步提高了合金强度。高熵合金独有的这些特性,使其在低温和高温条件下均有望表现出优异的物理性能和力学性能,引起了广泛的关注,研究报道呈爆发性增长。本文根据已有的BCC和fCC结构高熵合金物理-力学性能数据,分析了电子浓度、晶格常数、原子错配度、混合焓、硬度、弹性模量和归一化硬度等参数之间的关系,提出了BCC和fCC晶体结构的高熵合金弹性模量和硬度的经验计算公式,在此基础之上,综合考虑合金密度、塑性和服役工况等条件,提出了BCC和fCC结构的高熵合金成分设计方法。最后指出高熵合金的持久性能、大尺寸铸锭的成分和性能均匀性以及大尺寸合金锭的制备是高熵合金工程应用需解决的关键问题。

关键词：高熵合金电子浓度晶格常数晶格畸变混合焓硬度弹性模量归一化硬度

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Thermoluminescence characterization of natural and synthetic irradiated Ce-monazites

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Journal of Rare Earths 2024年第4期42卷 643-650页

作者： v.Correcher C.Boronat J.Garcia-Guinea J.f.Benavente T.Rivera-Montalvo CIEMAT Av.Complutense 4028040MadridSpain MNCN-CSIC J.Gutierrez Abascal 228006MadridSpain Instituto Politécnico Nacional CICATA-IPNAv.Legaria 694Mexico City11500Mexico

The thermoluminescence(TL)emission of synthetic and natural Ce-monazites was characterized here to determine the potential application in the identification of microscopic defects from a qualitative point of view trying to link each TL peak to a chemical-physical *** kinetic parameters that lead the luminescence processes were calculated by means of variable heating rate and computing glow curve deconvolution methods and allow identifying three groups of components at~90,130 and 290℃(for the mineral sample)and~90,170,220,270 and 320℃(for the synthetic CePO_(4):Nd_(0.20),La_(0.25)).The main differences appreciated in these complex TL curves are mainly due to(i)the content of impurities(natural sample contains lanthanides as well as U 0.60%and Th 5.22%)and(ii)the degree of crystallinity of the samples which is directly related to the type of impurities(synthetic monazite relies only on Nd and La).The behavior of the dose response in the range of 1-8 Gy is similar for both samples;the TL intensity increases linearly as the dose increases without changes in the position of the maxima,denoting first-order kinetic luminescence *** peak could be mostly associated with structural defects(i.e.,phase transitions),chemical reactions(i.e.,Ce3+?Ce4+redox reaction,dehydration or dehydroxylation processes)or intrinsic defects(i.e.,frenkel defects,ODCs or NBOHCs).

关键词： Thermoluminescence Kineticparameters Phosphate Ce-monazite Defects Rare earths

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Design of Biologically Active Macromolecular Ligands and Their Luminescent Complexes with Terbium Ions

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Chinese Journal of Polymer Science 2024年第5期42卷 604-611,I0007页

作者： Tatiana N.Nekrasova Andrei I.fischer Natalia A.Nesterova Anatoliy v.Dobrodumov Anzhelika v.Garshinina Olga D.Shuvaeva Natalya v.Zakharova Evgenii f.Panarin Institute of Macromolecular Compounds Russian Academy of Sciences31 Bolshoy pr.St Petersburg199004Russia Smorodintsev Research Institute of Influenza Russian Ministry of Health15/17 ul.prof.PopovaSt Petersburg197376Russia

Water-soluble copolymers of p-methacrylamidobenzoic acid(MABA)with neutral comonomers(N-vinylpyrrolidone(vP),N-methyl-N-vinylacetamide(MvAA),N-methacryloyl glucosamine(MAG))and anionic comononer sodium styrene sulfonate(NaSS)were synthesized by radical *** interactions between the prepared copolymers and Tb^(3+)ions in aqueous solutions were studied;the significant influence of chemical structure of a comonomer on luminescence intensity of Tb^(3+)complexes with the copolymers was *** luminescence intensity of Tb^(3+)complexes with the copolymers containing N-vinylamide units(vP,MvAA)is three times more intense than that observed for the complexes between Tb^(3+)and MAG-containing *** the case of NaSS-containing copolymers,the luminescence intensity is controlled by the values of binding constants between Tb^(3+)and MABA and the content of MABA units in a *** studied copolymers and their complexes with Tb^(3+)have low cytotoxicity and a pronounced antiviral activity against human respiratory syncytial virus.

关键词： Luminescence Water-soluble copolymers Lanthanide complexes Antiviral activity Cytotoxicity

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failure to Rescue as a Quality Metric in Congenital Heart Surgeries in a High-Complexity Service Provider Institution Located in a Middle-Income Country

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Congenital Heart Disease 2024年第2期19卷 207-218页

作者： Gustavo Cruz Santiago Pedroza Juan f.vélez Jessica Largo Juan f.Tejada Jorge H.Mejía-Mantilla Departamento de Anestesiología Fundación Valle del LiliCali760032Colombia Centro de Investigaciones Clínicas Fundación Valle del LiliCali760032Colombia Departamento de Cardiología Pediátrica Fundación Valle del LiliCali760032Colombia facultad de Medicina Universidad IcesiCali760031Colombia Unidad de Cuidado Intensivo Fundación Valle del LiliCali760032Colombia

Background:failure to rescue has been an effective quality metric in congenital heart ***,mor-bidity and mortality depend greatly on non-modifiable individual factors and have a weak correlation with better-quality *** aim to measure the complications,mortality,and risk factors in pediatric patients undergoing congenital heart surgery in a high-complexity institution located in a middle-income country and compare it with other institutions that have conducted a similar ***:A retrospective observational study was conducted in a high-complexity service provider institution,in Cali,*** pediatric patients undergoing any congenital heart surgery between 2019 and 2022 were *** main outcomes evaluated in the study were complication,mortality,and failure to rescue *** and multivariate logistic regression analysis was performed with mortality as the outcome ***:We evaluated 308 congenital heart *** the outcomes,201(65%)complications occurred,23(7.5%)patients died,and the fTR of the entire cohort was 11.4%.The presence of a postoperative complication(OR 14.88,CI 3.06–268.37,p=0.009),age(OR 0.79,CI 0.57–0.96,p=0.068),and urgent/emergent surgery(OR 8.14,CI 2.97–28.66,pficant variables in predicting ***:failure to rescue is an effective and comparable quality measure in healthcare institutions and is the major contributor to postoperative mortality in congenital heart *** our higher mortality and complication rate,we obtained a comparable failure to rescue rate to high-income countries’health institutions.

关键词： Congenital heart surgery complication mortality failure to rescue quality metric

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B-L model with D_(4)×Z_(4)×Z_(2)symmetry for fermion mass hierarchies and mixings

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Chinese Physics C 2024年第6期48卷 11-30页

作者： v.v.vien Department of Physics Tay Nguyen UniversityDaklakVietnam

We constructed a gauge B-L model with D_(4)×Z_(4)×Z_(2)symmetry to explain the quark and lepton mass hierarchies and their mixings with realistic CP phases via the type-I seesaw *** quark mases,three quark mixing angles,and the CP phase in the quark sector take the central values whereas Yukawa couplings in the quark sector are diluted in a range of difference of three orders of magnitude by the perturbation theory at the first *** the neutrino sector,a small neutrino mass is achieved by the type-I seesaw *** inverted and normal neutrino mass hierarchies are consistent with the experimental *** predicted sum of neutrino masses for normal and inverted hierarchies,the effective neutrino masses,and the Dirac CP phase are also consistent with recently reported limits.

关键词： flavor symmetries quark and lepton masses and mixing extensions of electroweak gauge sector neutrino mass and mixing non-standard-model neutrinos right-handed neutrinos D4 discrete symmetry

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Active and passive modulation of solar light transmittance in a uniquely multifunctional dual-band single molecule for smart window applications

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Journal of Energy Chemistry 2024年第1期88卷 293-305,I0007页

作者： Pooja v.Chavan Pramod v.Rathod Joohyung Lee Sergei v.Kostjuk Hern Kim Department of Energy Science and Technology Environmental Waste Recycle InstituteMyongji UniversityYonginGyeonggi-do 17058Republic of Korea Department of Chemical Engineering Myongji UniversityYonginGyeonggi-do 17058Republic of Korea Research Institute for Physical Chemical Problems of the Belarusian State University MinskBelarus

functional materials may change color by heat and electricity separately or simultaneously in smart *** materials have not only demonstrated remarkable potential in the modulation of solar radiation but are also leading to the development of indoor environments that are more comfortable and conducive to improving individuals'quality of ***,dual-responsive materials have not received ample research attention due to economic and technological *** a consequence,the broader utilization of smart windows faces *** address this new generational multistimulus responsive chromic materials,our group has adopted a developmental strategy to create a poly(NIPAM)n-Hv as a switchable material by anchoring active viologen(Hv)onto a phase-changing poly(NIPAM)n-based smart material for better utility and *** constructed smart windows facilitate individualistic reversible switching,from a highly transparent state to an opaque state(thermochromic)and a red state(electrochromic),as well as facilitate a simultaneous dual-stimuli response reversible switching from a clear transparent state to a fully opaque(thermochromic)and orange(electrochromic)*** privacy can be attained in smart windows designed for exclusive settings by achieving zero *** unique chromic mode operates independently and modulates visible and near-infrared(NIR)light in a distinct ***,these smart windows with thermal and electric dual-stimuli responsiveness demonstrate remarkable heat regulation capabilities,rendering them highly attractive for applications in building facades,energy harvesting,privacy protection,and color display.

关键词： Smart windows Thermochromism Electrochromism Energy saving Dual-responsive material

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Unravelling-based (auto)control of back-action in atomic Bose–Einstein condensate

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frontiers of physics 2024年第4期19卷 287-295页

作者： v.A.Tomilin L.v.Il’ichov Institute of Automation and Electrometry SB RAS 630090 NovosibirskRussia

We present a novel feedback control method for quantum *** does not affect the controlled system ***,it controls the unravelling of the quantum channel of interaction between the system and its *** interaction can be represented as a history of *** their informational content is changed,their back-action on the system is also *** action is trigged by the events,thus granting the system the degree of control over its own *** efficiency of the proposed scheme is demonstrated on the example of two-mode atomic Bose-Einstein condensate,with one of its modes subject to phase-contrast imaging in a Mach–Zehnder *** histories of photocounts in the output channels of the interferometer are used for *** capabilities of state engineering are studied for different settings of the feedback loop and different numbers of events in the recorded histories.

关键词： quantum feedback control quantum measurements twomode Bose-Einstein condensates

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The Radcliffe Wave Parameters from Data on Open Star Clusters

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Research in Astronomy and Astrophysics 2024年第3期24卷 106-109页

作者： v.v.Bobylev A.T.Bajkova Pulkovo Astronomical Observatory St-Petersburg 196140Russia

A spectral analysis of the vertical positions and velocities of 374 open star clusters(OSCs)was carried *** took these OSCs from the Hunt and Reffert catalog;they have an average age of about 10 million years,and are located on the galactic plane XY in a narrow zone inclined by 25°to the galactic axis *** following estimates of the parameters of the Radcliffe wave were obtained:(a)the maximum value in periodic perturbations of vertical coordinates Z_(max)=92±10pc with the wavelength of these perturbations λ_(z)=4.82±0.09 kpc;(b)the maximum value of the velocity of vertical disturbances Wmax=4.36±0.12km s^(-1) with disturbance wavelengthλ_(W)=1.78±0.02 *** that the results of the vertical velocity analysis are first-class in accuracy and completely new.

关键词： (Galaxy) local interstellar matter-Galaxy structure-(Galaxy) solar neighborhood

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Experimental and numerical investigation on alternatives to sandy gravel

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Defence Technology（防务技术） 2024年第1期31卷 130-141页

作者： v.Denefeld H.Aurich fraunhofer Institute for High-Speed Dynamics Ernst-Mach-Institut(EMI)Ernst-Zermelo-Str.479104FreiburgGermany fraunhofer Institute for High-Speed Dynamics Ernst-Mach-Institut(EMI)Am Christianswuhr 279400KandernGermany

The NATO agreement STANAG 4569 defines the protection levels for the occupants of logistic and light armored *** Allied Engineering Publication,AEP-55,volume 2 document outlines the test conditions for underbelly improvised explosive device(IEDs),which must be buried in water-saturated sandy *** use of sandy gravel has some drawbacks,for instance reproducibility,time consumption,and *** paper focuses on the investigation of four alternatives to sandy gravel,which could produce similar specific and cumulative impulses:a concrete pot filled with water,a concrete pot filled with quartz sand,a steel pot without filling and a concrete pot filled with glass spheres(diameter 200μm—300μm)and different water *** impulses are measured with a ring technology developed at the fraunhofer EMI.A numerical soil model based on the work of Marrs,2014 and fi serov a,2006 and considering the soil moisture was used to simulate the experiments with glass spheres at different water contents,showing much better agreement with the experiments than the classical Laine&Sandvik model,even for high saturation *** results can be used to create new test conditions at original scale that are more cost-effective,more reproducible and simpler to manage in comparison to the current tests carried out with STANAG sandy gravel.

关键词： Improvised explosive device(IED) Specific impulse Momentum transfer Sandy gravel Glass spheres Numerical model Soil moisture

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