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Defence Technology（防务技术） 2018年第5期14卷 446-450页

作者： o.s.I.Fayomi L.R.Kanyane A.P.I.Popoola s.o.oyedepo Department of Chemical Metallurgical and Materials EngineeringTshwane University of TechnologyP.M.B.X680PretoriaSouth Africa Department of Mechanical Engineering Covenant UniversityP.M.B 1023OtaNigeria

Despite the massive usages of low carbon steel in automobile for engineering components, its corrosion and high friction coefficient in aggressive environment make it limited in service. This paper is aimed at modifying low carbon steel structural component with thin film composite for enhanced mechanical and corrosion properties. The steel structure was electrodeposited with Zn-V_2 o_5 and embedded with varied Nbo_2 weight concentration of 6-12 wt % based electrolyte. scanning electron microscope(sEM) and high optical microscope was used to study the microstructural evolution of the fabricated coatings. The thermal stability of the fabricated coatings was studied in an isothermal furnace at 300 ℃ and 600 ℃ and further characterized using a high tech optical microscope. Potentiodynamic polarization technique was used to investigate the corrosion behavior of the composites in 3.65% NaCl. From the result, the effect of Nbo_2 on Zn-V_2 o_5-Nbo_2 was massive with improved crystal grain within the coatings lattices. The coating possesses strong metallurgical bonding and good corrosion resistance properties of about 0.315 mm/yr corrosion rate compare to 4.1 mm/yr of as-received sample. No doubt the impact of thermal shock on the resilient characteristics of the composite coating was moderate owing to the stable adherent properties of the deposited coatings.

关键词： Electrodeposition Low carbon steel Micro-hardness Thermal stability corrosion behavior Rare earth metal(REM)

sustainable Biocomposites Materials for Automotive Brake Pad Application:An overview

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Journal of Renewable Materials 2024年第3期12卷 485-511页

作者： Joseph o.Dirisu Imhade P.okokpujie olufunmilayo o.Joseph sunday o.oyedepo oluwasegun Falodun Lagouge K.Tartibu Firdaussi D.shehu Department of Mechanical Engineering Covenant UniversityOtaOgunNigeria Department of Mechanical and Mechatronics Engineering AFE Babalola UniversityAdoEkitiNigeria Department of Mechanical and Industrial Engineering Technology University of JohannesburgJohannesburg2028South Africa school of Chemical and Metallurgical Engineering University of the WitwatersrandJohannesburgSouth Africa

Research into converting waste into viable eco-friendly products has gained global *** natural fibres and pulverized metallic waste becomes necessary to reduce noxious environmental emissions due to indiscriminately occupying the *** study reviews the literature in the broad area of green composites in search of materials that can be used in automotive brake *** made by biocomposite,rather than fossil fuels,will be favoured.A database containing the tribo-mechanical performance of numerous potential components for the future green composite was established using the technical details of bio-polymers and natural *** development of materials with diverse compositions and varying proportions is now conceivable,and these materials can be permanently connected in fully regulated *** explanation demonstrates that all of these variables affect friction coefficient,resistance to wear from friction and high temperatures,and the operating life of brake pads to varying *** this study,renewable materials for the matrix and reinforcement are screened to determine which have sufficient strength,coefficient of friction,wear resistance properties,and reasonable costs,making them a feasible option for a green *** most significant,intriguing,and unusual materials used in manufacturing brake pads are gathered in this review,which also analyzes how they affect the tribological characteristics of the pads.

关键词： Asbestos brake pad biocomposites green composite mechanical properties natural reinforcement waste

A review on the scale-up of high-shear wet granulation processes and the impact of process parameters

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Particuology 2024年第9期92卷 180-195页

作者： Ana Rita Alves Marta Filipe simões sérgio simões João Gomes University of Coimbra CERESDepartment of Chemical EngineeringFaculty of Sciences and TechnologyRua Sílvio Lima3030-790CoimbraPortugal Bluepharma-Indústria Farmacêutica São Martinho do BispoCoimbra3045-016Portugal Faculty of Pharmacy University of CoimbraAzinhaga de Santa Comba3000-548CoimbraPortugal

Wet granulation is one of the most important agglomeration processes,and high-shear granulation(HsG)one of the most employed technologies in the pharmaceutical *** most critical process parameters of HsG are discussed in this *** main concern in scaling up the wet granulation process is the differences between scales,which prevent the particles from having the same experience across all *** scale-up of wet granulation processes is commonly divided into two categories:engineering and attribute-based *** engineering-based scale-up approach is a strategy based on dimensional analysis and an attribute-based supported on the principles of“equifinality”,where process variables are adjusted to obtain equivalent granule *** work presents the effect of different HsG process parameters on the scale-up,as well as the use of process analytical tools(PAT)and modelling *** aim is to review applied scale-up approaches in HsG and discuss benefits and *** is proven why the scale-up for oral solid pharmaceutical products is still considered a hot topic and a very challenging task for development and engineering teams.

关键词： High-shear wetgranulation Parametric-based Attribute-based Physics-based modelling Impeller design scale-up

Myelin histology:a key tool in nervous system research

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Neural Regeneration Research 2024年第2期19卷 277-281页

作者： Óscar Darío García-García Víctor Carriel Jesús Chato-Astrain Department of Histology Tissue Engineering GroupUniversity of Granada&Instituto de Investigación Biosanitaria ibs.GRANADAGranadaSpain

The myelin sheath is a lipoprotein-rich,multilayered structure capable of increasing conduction velocity in central and peripheral myelinated nerve *** to the complex structure and composition of myelin,various histological techniques have been developed over the centuries to evaluate myelin under normal,pathological or experimental ***,methods to assess myelin integrity or content are key tools in both clinical diagnosis and neuroscience *** this review,we provide an updated summary of the composition and structure of the myelin sheath and discuss some histological procedures,from tissue fixation and processing techniques to the most used and practical myelin histological staining *** the lipoprotein nature of myelin,the main features and technical details of the different available methods that can be used to evaluate the lipid or protein components of myelin are described,as well as the precise ultrastructural techniques.

关键词： fluorescence microscopy histology light microscopy lipid histochemistry metallographic techniques myelin histochemistry myelin immunohistochemistry myelin structure&composition myelin ultrastructural evaluation tissue fixation&processing

Collective coherent emission of electrons in strong laser fields and perspective for hard x-ray lasers

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Matter and Radiation at Extremes 2024年第2期9卷 1-3页

作者： E.G.Gelfer A.M.Fedotov o.Klimo s.Weber Extreme Light Infrastructure ERIC ELI Beamlines Facility25241 Dolní BřežanyCzech Republic HiLAsE Centre Institute of Physics of the Czech Academy of Sciences25241 Dolní BřežanyCzech Republic National Research Nuclear University MEPhI Moscow 115409Russia FNsPE Czech Technical University in Prague11519 PragueCzech Republic

Coherent motion of particles in a plasma can imprint itself on *** recent advent of high-power lasers—allowing the nonlinear inverse Compton-scattering regime to be reached—has opened the possibility of looking at collective effects in laser–plasma *** certain conditions,the collective interaction of many electrons with a laser pulse can generate coherent radiation in the hard x-ray *** perspective paper explains the limitations under which such a regime might be attained.

关键词： laser scattering coherent

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

Rotating effects on the photoionization cross-section of a 2D quantum ring

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Communications in Theoretical Physics 2024年第10期 153-159页

作者： Carlos Magno o Pereira Frankbelson dos s Azevedo Luís Fernando C Pereira Edilberto o silva Departamento de Física Universidade Federal do Maranh?o

In this article, we investigate the nonrelativistic quantum motion of a charged particle within a rotating frame, taking into account the Aharonov–Bohm(AB) effect and a uniform magnetic field. our analysis entails the derivation of the equation of motion and the corresponding radial equation to describe the system. solving the resulting radial equation enables us to determine the eigenvalues and eigenfunctions, providing a clear expression for the energy levels. Furthermore,our numerical analysis highlights the substantial influence of rotation on both energy levels and optical properties. specifically, we evaluate the photoionization cross-section with and without the effects of rotation. To elucidate the impact of rotation on the photoionization process of the system, we present graphics that offer an appealing visualization of the intrinsic nature of the physics involved.

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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

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stability analysis of a time-delayed Van der Pol–Helmholtz–Duffing oscillator in fractal space with a non-perturbative approach

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Communications in Theoretical Physics 2024年第4期76卷 22-31页

作者： Yusry o El-Dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The time-delayed fractal Van der Pol–Helmholtz–Duffing(VPHD)oscillator is the subject of this paper,which explores its mechanisms and highlights its stability *** time-delayed technologies are currently garnering significant attention,the focus of this research remains crucially relevant.A non-perturbative approach is employed to refine and set the stage for the system under *** innovative methodologies introduced yield an equivalent linear differential equation,mirroring the inherent nonlinearities of the ***,the incorporation of quadratic nonlinearity into the frequency formula represents a cutting-edge *** analytical solution's validity is corroborated using a numerical *** conditions are ascertained through the residual Galerkin ***,it is observed that the delay parameter,in the context of the fractal system,reverses its stabilizing influence,impacting both the amplitude of delayed velocity and the *** analytical solution's precision is underscored by its close alignment with numerical ***,the study reveals that fractal characteristics emulate damping *** its applicability across diverse nonlinear dynamical systems,this non-perturbative approach emerges as a promising avenue for future research.

关键词： Van der Pol-Helmholtz-Duffing oscillator fractal space time-delay non-perturbative approach stability analysis El-Dib's frequency formula

Highly Defective Dark Tio_(2) Modified with Pt: Effects of Precursor Nature and Preparation Method on Photocatalytic Properties

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Transactions of Tianjin University 2024年第2期30卷 198-209页

作者： E.D.Fakhrutdinova o.A.Reutova T.A.Bugrova I.Yu.ovsyuk L.s.Kibis o.A.stonkus D.B.Vasilchenko o.V.Vodyankina V.A.svetlychnyi National Research Tomsk state University TomskRussia 634050 Novosibirsk state University NovosibirskRussia 630090 Boreskov Institute of Catalysis NovosibirskRussia 630090 Nikolaev Institute of Inorganic Chemistry NovosibirskRussia 630090

The study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibited similar phase compositions, specific surface areas, and Pt contents. High-resolution transmission electron microscopy coupled with pulsed Co adsorption revealed increased dispersity when photoreduction and the hydroxonitrate complex (Me _(4) N) _(2) [Pt _(2) (oH) _(2) (No _(3) ) _(8) ] were used. The sample featured a high content of single-atom species and subnano-sized Pt clusters. The X-ray photoelectron spectroscopy results showed that the photoreduction method facilitated the appearance of a larger number of Pt ^(2+) states, which appeared owing to the strong metal-support interaction (sMsI) eff ect of the transfer of electron density from the electron-saturated defects on the Tio _(2) surface to Pt ^(4+) . In the hydrogen evolution reaction, samples with a significant fraction of the Pt ^(2+) ionic component, capable of generating short-lived Pt^(0) single-atom sites under irradiation due to the sMsI eff ect, exhibited the highest photocatalytic activity. The 0.5Pt(C)/Tio_(2) -Ph sample exhibited the highest hydrogen yield with a quantum efficiency of 0.53, retaining its activity even after 8 h of operation.

关键词： Dark(black)Tio_(2) Pulsed laser ablation Platinum reduction method Precursor type Photocatalysis Hydrogen evolution reaction