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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

Green hydrogen energy production:current status and potential

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Clean Energy 2024年第2期8卷 1-7页

作者： Ali o.m.maka mubbashar mehmood The Libyan Centre for Research and Development of saharian Communities MurzuqLibya school of Engineering and Physical sciences Heriot-Watt UniversityEdinburghEH144ASUK

The technique of producing hydrogen by utilizing green and renewable energy sources is called green hydrogen ***,by implementing this technique,hydrogen will become a sustainable and clean energy source by lowering greenhouse gas emissions and reducing our reliance on fossil *** key benefit of producing green hydrogen by utilizing green energy is that no harmful pollutants or greenhouse gases are directly released throughout the ***,to guarantee all of the environmental advantages,it is crucial to consider the entire hydrogen supply chain,involving storage,transportation and end *** is a promising clean energy source and targets plan pathways towards decarbonization and net-zero emissions by *** paper has highlighted the techniques for generating green hydrogen that are needed for a clean environment and sustainable energy ***,it summarizes an overview,outlook and energy transient of green hydrogen ***,its perspective provides new insights and research directions in order to accelerate the development and identify the potential of green hydrogen production.

关键词： green hydrogen energy hydrogen production energy transition clean energy perspective of green hydrogen

High-precision inverse potentials for neutron-proton scattering using piece-wise smooth morse functions

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Chinese Physics C 2024年第10期48卷 201-213页

作者： Ayushi Awasthi Arushi sharma Ishwar Kant o.s.K.s.sastri Department of Physics and Astronomical science Central University of Himachal PradeshDharmshala176215India

The aim of this study is to construct inverse potentials for various ℓ-channels of neutron-proton scattering using a piece-wise smooth morse function as a *** phase equations for single-channel states and the coupled equations of multi-channel scattering are solved numerically using the 5^(th) order Runge-kutta *** employ a piece-wise smooth reference potential comprising three morse functions as the initial *** a machine learning-based genetic algorithm,we optimize the model parameters to minimize the mean-squared error between simulated and anticipated phase *** approach yields inverse potentials for both single and multichannel scattering,achieving convergence to a mean-squared error≤10^(-3).The resulting scattering lengths"a_(0)"and effective ranges"r"for ^(3)s_(1) and ^(1)s_(0) states,expressed as[a_(0),r],are found to be[5.445(5.424),1.770(1.760)]and[–23.741(–23.749),2.63(2.81)],respectively;these values are in excellent agreement with experimental ***,the calculated total scattering cross-sections are highly consistent with their experimental counterparts,having a percentage error of less than 1%.This computational approach can be easily extended to obtain interaction potentials for charged particle scattering.

关键词： inverse potentials neutron-proton scattering piece-wise smooth morse function phase function method reference potential approach genetic algorithm

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.Yakout 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 aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount *** the current study, we report the photocatalytic characteristics 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 above 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

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 Hamah sor Ahmed Farouk Deifalla Paul o.Awoyera Nadia Gouider Civil Engineering Laboratory 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 native herbaceous community exerts a strong allelopathic effect on the woody range-expander Betula fruticosa

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Journal of Plant Ecology 2024年第4期17卷 131-140页

作者： Lichao Wang Ayub m.o.oduor Yanjie Liu state Key Laboratory of Black soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China University of Chinese Academy of sciences Beijing 100049China Department of Applied Biology Technical University of KenyaNairobiKenya

Biological invasions by alien and range-expanding native plant species can suppress native plants through ***,the homeland security hypothesis suggests that some native plants can resist invasion by producing allelopathic compounds that inhibit the growth of invasive *** research has focused on allelopathic interactions between individual native and invasive plant species,with less emphasis on how allelopathy helps entire native communities resist ***,limited knowledge exists about allelopathic interactions between range-expanding native species and recipient native communities,and their influence on invasion *** bridge this knowledge gap,we conducted two greenhouse competition experiments to test reciprocal allelopathic effects between a native woody range-expanding species,Betula fruticosa,and a community of four native herbaceous species(sanguisorba officinalis,Gentiana manshurica,sium suave and Deyeuxia angustifolia)in *** assessed whether *** and the native community differed in their competitive effects and responses,and whether these were influenced by activated carbon,which neutralizes allelochemicals in the *** carbon reduced the suppressive effects of the native community on the above-ground biomass of ***,which indicates that the native community exerted a strong allelopathic effect on *** contrast,activated carbon only marginally enhanced the suppressive effects of *** on the native community,which indicates that allelopathy is not the primary mechanism by which *** exerts its ***,these findings support the homeland security hypothesis and suggest that biotic resistance from the native herbaceous community may limit the invasion success of the woody range-expander ***.

关键词： allelochemicals competition encroachment global change non-native shrub

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 around 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.Barnyakov s.samoylov D.Nikiforov V.Ivanov m.Arsentyeva D.Chekmenev o.Pavlov I.Pivovarov 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,along with discussions on the measurement of its parameters.

关键词： Klystron Linear accelerator Electron beam

Hydrochar and synthetic natural gas co-production for a full circular economy implementation via hydrothermal carbonization and methanation:An economic approach

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Journal of Environmental sciences 2024年第6期140卷 69-78页

作者： Judith González-Arias Guillermo Torres-sempere miriam González-Castaño Francisco mBaena-moreno Tomás RReina Inorganic Chemistry Department and materials sciences Institute University of Seville-CSICSevilleSpain materials sciences Institute(ICmsE) CSIC-University of SevilleSevilleSpain Department of Chemistry and Chemical Engineering Chalmers University of TechnologyGothenburgSE 41296Sweden

Herein we study the economic performance of hydrochar and synthetic natural gas coproduction from olive tree *** process entails a combination of hydrothermal carbonization and *** a previous work,we evidenced that standalone hydrochar production via HTC results ***,we propose a step forward on the process design by implementing a methanation,adding value to the gas effluent in an attempt to boost the overall process techno-economic *** different plant capacities were analyzed(312.5,625 and 1250 kg/hr).The baseline scenarios showed that,under the current circumstances,our circular economy strategy in *** analysis of the revenues shows that hydrochar selling price have a high impact on NPV and subsidies for renewable coal production could help to boost the profitability of the *** the contrary,the analysis for natural gas prices reveals that prices 8 times higher than the current ones in spain must be achieved to reach *** seems unlikely even under the presence of a strong subsidy *** costs analysis suggests that a remarkable electricity cost reduction or electricity consumption of the HTC stage could be a potential strategy to reach profitability ***,significant reduction of green hydrogen production costs is deemed instrumental to improve the economic performance of the *** results show the formidable techno-economic challenge that our society faces in the path towards circular economy societies.

关键词： Hydrothermal carbonization Co_(2)waste valorization methanation Profitability analysis