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Adsorption of yttrium(Y^(3+)) and concentration of rare earth elements from phosphogypsum using chitin and chitin aerogel

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Journal of Rare Earths 2024年第4期42卷 775-782页

作者： Glaydson s.dos Reis Diana Pinto sabrina f.lütke Eder C.lima luis f.O.silva Irineu A.s.De Brum Guilherme l.Dotto Department of forest Biomaterials and Technology Biomass Technology Centre Swedish University of Agricultural SciencesUmeaE13Swedn Universidad De la Costa Calle 58#55-66080002BarranquillaAtlanticoColombia Research Group on Adsorptive and Catalytic Process Engineering(ENGEPAC) Federal University of Santa MariaAv.Roraima100079705900Santa MariaRSBrazil Institute of Chemistry Federal University of Rio Grande do Sul90040060Porto AlegreBrazil

Chitin powder and chitin-aerogel were prepared from shrimp wastes and used to uptake Y^(3+)from aqueous solutions and concentrate this rare earth element from phosphogypsum(PG).Chitin aerogel displays a specific surface area of 945 m^(2)/g,while chitin powder is 3.6 m^(2)/g,which largely influences its adsorption *** the adsorption in synthetic solutions,the effect of pH on Y^(3+)removal is strong for chitin powder *** contrast,no big pH influence was detected for chitin *** interactions and chelation can highlight the proposed mechanism of Y^(3+)on chitin adsorbents for the powder and ***,in addition to these interactions,pore filling/pore diffusion is the main mechanism of Y^(3+)removal in the chitin *** aerogel is efficient in concentrating 8 times the Y^(3+)from PG,a very complex *** complex chitin aerogel-Y^(3+)can be a secondary source of rare earth elements for other applications.

关键词： Rare earths sustainable material Chitin powder Chitin porous aerogel Yttrium adsorption and recovery

Cognition and movement in neurodegenerative disorders:a dynamic duo

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Neural Regeneration Research 2024年第10期19卷 2101-2102页

作者： Marit f.l.Ruitenberg Department of Health Medical and NeuropsychologyLeiden UniversityLeidenthe Netherlands leiden Institute for Brain and Cognition Leidenthe Netherlands

People with neurodegenerative disorders often experience problems across a variety of functional domains,including cognition,movement,and psychosocial *** classification of these disorders is based on the phenotypical manifestations that represent the most prominent clinical *** example,Parkinson's disease and Huntington's disease are typically regarded as movement disorders,whereas Alzheimer's disease(AD) and other dementias are regarded as cognitive disorders.

关键词： disorders Huntington degenerative

Two-stream Approximation to the Radiative Transfer Equation:A New Improvement and Comparative Accuracy with Existing Methods

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Advances in Atmospheric sciences 2024年第2期41卷 278-292页

作者： f.Momo TEMGOUA l.Akana NGUIMDO DNJOMO Environmental Energy Technologies laboratory(EETl) Faculty of SciencesUniversity of YaoundéPO Box 812 YaoundéCameroon Department of Electrical and Electronic Engineering Faculty of Engineering and TechnologyUniversity of BueaPO Box 63 BueaCameroon

Mathematical modeling of the interaction between solar radiation and the Earth's atmosphere is formalized by the radiative transfer equation(RTE), whose resolution calls for two-stream approximations among other methods. This paper proposes a new two-stream approximation of the RTE with the development of the phase function and the intensity into a third-order series of legendre polynomials. This new approach, which adds one more term in the expression of the intensity and the phase function, allows in the conditions of a plane parallel atmosphere a new mathematical formulation of γparameters. It is then compared to the Eddington, Hemispheric Constant, Quadrature, Combined Delta function and Modified Eddington, and second-order approximation methods with reference to the Discrete Ordinate(Disort) method(δ –128 streams), considered as the most precise. This work also determines the conversion function of the proposed New Method using the fundamental definition of two-stream approximation(f-TsA) developed in a previous work. Notably,New Method has generally better precision compared to the second-order approximation and Hemispheric Constant methods. Compared to the Quadrature and Eddington methods, New Method shows very good precision for wide domains of the zenith angle μ 0, but tends to deviate from the Disort method with the zenith angle, especially for high values of optical thickness. In spite of this divergence in reflectance for high values of optical thickness, very strong correlation with the Disort method(R ≈ 1) was obtained for most cases of optical thickness in this study. An analysis of the legendre polynomial series for simple functions shows that the high precision is due to the fact that the approximated functions ameliorate the accuracy when the order of approximation increases, although it has been proven that there is a limit order depending on the function from which the precision is lost. This observation indicates that increasing the order of app

关键词： Radiative Transfer Equation two-stream method legendre polynomial optical thickness moments of specific intensity conversion function transmittance reflectance

Experimental implementation of phase triplicator gratings in a spatial light modulator

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Chinese Optics letters 2024年第2期22卷 64-69页

作者：高尚 María del Mar sánchez-lópez Ignacio Moreno Instituto de Bioingeniería Universidad Miguel HernándezElche 03202Spain Departamento de física Aplicada Universidad Miguel HernándezElche 03202Spain Departamento de Ciencia de Materiales Óptica y Tec.Electr´onicaUniversidad Miguel HernándezElche 03202Spain

In this work,we compare different methods for implementing a triplicator,a phase grating that generates three equiintense diffraction *** design with optimal efficiency features a continuous phase profile,which cannot be easily reproduced,and is typically affected by *** compare its performance with binary and sinusoidal phase *** also analyze the effect of quantizing the phase ***,a random approach is adopted to eliminate the additional harmonic *** all cases,a liquid-crystal-on-silicon spatial light modulator is employed to experimentally verify and compare the different approaches.

关键词： diffraction gratings phase modulation triplicator spatial light modulators

Development of an ultrathin liquid sheet target for laser ion acceleration at high repetition rates in the kilohertz range

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High Power laser science and Engineering 2024年第3期12卷 134-145页

作者： M.füle A.P.Kovács T.Gilinger M.Karnok P.Gaál s.figul G.Marowsky K.Osvay National laser-Initiated Transmutation laboratory University of SzegedSzegedHungary Department of Experimental Physics University of SzegedSzegedHungary ElI AlPs ELI-HU Non-Profit Ltd.SzegedHungary Department of Optics and Quantum Electronics University of SzegedSzegedHungary Advanced Microfluidic systems GmbH GöttingenGermany

A colliding microjet liquid sheet target system was developed and tested for pairs of round nozzles of 10,11 and 18μm in *** sheet's position stability was found to be better than a few *** interaction with 50 mJ laser pulses,the 18μm jet has a resonance amplitude of 16μm at a repetition rate of 33 Hz,while towards 100 Hz it converges to 10μm for all nozzles.A white-light interferometric system was developed to measure the liquid sheet thickness in the target chamber both in air and in vacuum,with a measurement range of 182 nm±1μm and an accuracy of±3%.The overall shape and 3D shape of the sheet follow the Hasson±Peck model in *** vacuum versus air,the sheet gradually loses 10%of its thickness,so the thinnest sheet achieved was below 200 nm at a vacuum level of 10±4mbar,and remained stable for several hours of operation.

关键词： diagnostics laser ion acceleration nanometric liquid sheet targets vacuum test

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 Renato 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 amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

localized-states quantum confinement induced by roughness in CdMnTe/CdTe heterostructures grown on si(111) substrates

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Journal of semiconductors 2024年第9期45卷 28-35页

作者： leonarde N.Rodrigues Wesley f.Inoch Marcos l.f.Gomes Odilon D.D.Couto Jr. Bráulio s.Archanjo sukarno O.ferreira Physics Department Federal University of ViçosaViçosa36570-900Minas GeraisBrazil Instituto de física Gleb Wataghin Universidade Estadual de CampinasCampinas13083-859São PauloBrazil National Institute of Metrology Quality and Technology(Inmetro) Materials Metrology Division(DIMAT)Xerém2525-020Rio de JaneiroBrazil

This work shows that despite a lattice mismatch of almost 20%, CdMnTe/CdTe/CdMnTe heterostructures grown directly on si(111) have surprisingly good optical emission properties. The investigated structures were grown by molecular beam epitaxy and characterized by scanning transmission electron microscopy, macro-and micro-photoluminescence. low temperature macro-photoluminescence experiments indicate three emission bands which depend on the CdTe layer thickness and have different confinement characteristics. Temperature measurements reveal that the lower energy emission band (at 1.48 eV)is associated to defects and bound exciton states, while the main emission at 1.61 eV has a weak 2D character and the higher energy one at 1.71 eV has a well-defined (zero-dimensional, 0D) 0D nature. Micro-photoluminescence measurements show the existence of sharp and strongly circularly polarized (up to 40%) emission lines which can be related to the presence of Mn in the heterostructure. This result opens the possibility of producing photon sources with the typical spin control of the diluted magnetic semiconductors using the low-cost silicon technology.

关键词： CdMnTe/CdTe/CdMnTe heterostructure CdTe/CdMnTe quantum emitters quantum dot-like emission silicon(111)substrate

fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

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Matter and Radiation at Extremes 2024年第3期9卷 11-18页

作者： Y.X.Wang X.l.Zhu s.M.Weng P.li X.f.li H.Ai H.R.Pan Z.M.sheng Key laboratory for laser Plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IfsA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of laser fusion of China Academy of Engineering Physics MianyangSichuan 621900China state key laboratory of High field laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

The generation of ultrashort high-power light sources in the mid-infrared(mid-IR)to terahertz(THz)range is of interest for applications in a number of fields,from fundamental research to biology and *** conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-IR or THz ***,we present a photon deceleration scheme for the efficient generation of ultrashort mid-IR or THz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long *** signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by the driver *** to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index in the plasma wake ***,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer *** greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength IR and THz spectral ranges.

关键词： laser ultrashort photon

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

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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