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Wettability,reactivity,and interface structure in Mg/Ni system

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journal of Magnesium and Alloys 2024年第2期12卷 659-672页

作者： S.Terlicka N.Sobczak Ł.Maj P.darłak j.j.Sobczak Institute of Metallurgy and Materials Science Polish Academy of Sciences25 Reymonta Str.KrakowPoland Faculty of Foundry Engineering AGH University23 Reymonta Str.KrakowPoland

The sessile drop method was applied to the experimental investigation of the wetting and spreading behaviors of liquid Mg drops on pure Ni *** comparison,the experiments were performed in two variants:(1)using the Capillary Purification(CP)procedure,which allows the non-contact heating and squeezing of a pure oxide-free Mg drop;(2)by classical Contact Heating(CH)*** high-temperature tests were performed under isothermal conditions(CP:760℃for 30 s;CH:715℃for 300 s)using Ar+5 wt%H_(2) *** the sessile drop tests,images of the Mg/Ni couples were recorded by CCD cameras(57 fps),which were then applied to calculate the contact angles of metal/substrate *** and transmission electron microscopy analyses,both coupled with energy-dispersive X-ray spectroscopy,were used for detailed structural characterization of the solidified *** was found that an oxide-free Mg drop obtained by the CP procedure showed a wetting phenomenon on the Ni substrate(an average contact angleθ<90°in<1 s),followed by fast spreading and good wetting over the Ni substrate(θ_((CP))~20°in 5 s)to form a final contact angle ofθ_(f(CP))~18°.In contrast,a different wetting behavior was observed for the CH procedure,where the unavoidable primary oxide film on the Mg surface blocked the spreading of liquid Mg showing apparently non-wetting behavior after 300 s contact at the test ***,in both cases,the deep craters formed in the Ni substrates under the Mg drops and significant change in the structure of initially pure Mg drops to Mg-Ni alloys suggest a strong dissolution of Ni in liquid Mg and apparent values of the final contact angles measured for the Mg/Ni system.

关键词： Magnesium-based alloys Sessile drop tests Capillary purification procedure Wettability Reactivity Contact angle

Bird species present in urban parks are more colorful than urban avoiders:A test in the Argentinian Pampas

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Avian Research 2024年第1期15卷 22-26页

作者： lucas M.Leveau Departamento de Ecología Genetica y EvolucionFacultad de Ciencias Exactas y NaturalesUniversidad de Buenos Aires-IEGEBA(CONICET-UBA)Intendente Güiraldes 2160Ciudad UniversitariaC1428EGABuenos AiresArgentina

Bird plumage color has been assessed as a possible trait driving the presence of bird species in urban *** some species can see the ultraviolet(UV) spectrum,the mentioned studies did not take into account UV reflectance when characterizing bird *** study aimed to use a recent database of the colorfulness in passerines that incorporated the UV spectrum to compare bird colorfulness and other traits between urban parks and rural areas in Central-East *** in urban parks were surveyed in 51 parks in 6 cities during breeding and non-breeding seasons.A list of Passeriformes species from parks was created,and a list of urban avoider species was created from the *** traits were body mass,clutch size,migratory status,nesting site,diet and habitat breadth,and plumage colorfulness.A total of 85 species were detected in the regional pool,of which 30 species were detected in urban *** species present in urban parks were more colorful than bird species only present in rural *** addition,bird presence in urban parks was positively related to their regional frequency and diet ***,urban presence was related to nesting on trees and buildings,whereas species not present in urban parks nested on the *** results obtained showed that bird color is significantly associated with presence of bird species in urban parks.

关键词： Avian Filter Phenotype Selection Ultraviolet

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

Larval development and voracity of Eupeodes americanus (Diptera: Syrphidae): comparison of the focal prey Aphis gossypi (Hemiptera: Aphididae) and the banker prey Rhopalosiphum padi (Hemiptera: Aphididae)

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Insect Science 2024年第2期31卷 575-586页

作者： Arlette Fauteux Antonio Onofre Soares Eric lucas Laboratoire de lutte biologique Departement des sciences biologiquesUniversite du Quebec a Montreal(UQAM)MontrealQuebecCanada Faculty of Science and Technology Center for Ecology Evolution and Environmental ChangesAzorean Biodiversity Group(cE3c-ABG)&CHANGE-Global Change and Sustainability InstitutePonta DelgadaPortugal

Unlike European species,the potential of Nearctic syrphids as biological control agents is still poorly ***,the American hoverfly,Eupeodes americanus(Wiedemann),has recently demonstrated promising traits as a biocontrol agent,notably against the foxglove aphid,Aulacorthum solani Kaltenbach,on *** present study aims to extend our knowledge of the American hoverfly by evaluating its potential as a biocontrol agent in a banker plant system against the melon aphid,Aphis gossypi Glover,in a greenhouse cucumber *** preimaginal development and voracity of *** were compared when preying upon the focal prey/pest(***)or the banker prey(bird cherry-oat aphid,Rhopalosiphum padi L.)by daily observations of larvae from egg to *** development time,survival rate,and occurrence of deformation were similar on both prey *** weight of third instar and pupae,however,was higher for larvae that fed on the banker *** ad libitum voracity of the syrphid larvae was generally very high and did not significantly differ between prey species,except for the third-instar larvae which consumed more focal *** suggest that a banker plant system involving the bird cherry-oat aphid may be a promising tactic for utilizing *** for melon aphid biocontrol.

关键词： american hoverfly banker plant system biological control bird cherry-oat aphid greenhouse cucumber melon aphid

New therapy for metabolic syndrome:Gut microbiome supplementation

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World journal of Diabetes 2024年第9期15卷 1833-1836页

作者： Waseem Qureshi Maqsood Ahmad dar Mohd Younis Rather Hospital Administration Government Medical CollegeUniversity of KashmirJammu and KashmirSrinagar 190010India Department of Medicine Government Medical CollegeUniversity of KashmirJammu and KashmirSrinagar 190010India Multidisciplinary Research Unit Government Medical CollegeUniversity of KashmirJammu and KashmirSrinagar 190010India

The gut microbiota is important in the development and progression of metabolic illnesses such type 2 diabetes,cardiovascular disease(CVD),and *** diverse community of microorganisms controls a variety of physiological functions,including metabolism,inflammation,and immune *** these interactions has resulted in novel therapeutic options,including microbiome *** gut microbiome is extremely susceptible to dietary changes,which can alter its makeup and function,influencing metabolite synthesis that affects host *** metabolites,such as butyrate and propionate,have been proven to protect against metabolic illnesses,whereas trimethylamine has been linked to ***,probiotics,synbiotics,and postbiotics are being investigated by researchers as ways to change the gut microbiome and boost metabolic *** advances in therapy and lifestyle adjustments,the prevalence of metabolic syndrome is increasing,emphasizing the need for new medicines.

关键词： Probiotics Prebiotics Synbiotics Postbiotics Microbiome Type 2 diabetes mellitus Cardiovascular disease Obesity

A reduced model for particle calcination for use in DEM/CFD simulations

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Particuology 2024年第10期93卷 316-327页

作者： lucas Mieg Torben Bergold Enric Illana Mahiques Viktor Scherer Martin Mönnigmann Automatic Control and System Theory Ruhr University BochumGermany Energy Plant Technology Ruhr University BochumGermany

We treat the accurate simulation of the calcination reaction in particles,where the particles are large and,thus,the inner-particle processes must be *** these processes need to be described with coupled partial differential equations(PDEs)that must be solved numerically,the computation times for a single particle are too high for use in simulations that involve many *** of this type arise when the Discrete Element Method(DEM)is combined with Computational Fluid Dynamics(CFD)to investigate industrial systems such as quicklime production in lime shaft *** show that,based on proper orthogonal decomposition and Galerkin projection,reduced models can be derived for single particles that provide the same spatial and temporal resolution as the original PDE models at a considerably reduced computational *** the finite volume particle models with the reduced models results in an overall reduction of the reactor simulation time by about 40%for the sample system treated here.

关键词： Calcination Reactive bulk Model reduction Discrete element method Galerkin projection

Optoelectronic and thermoelectric properties of spinel chalcogenides HgLa2X4（X=S and Se）:A first-principles study

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journal of Rare Earths 2024年第10期42卷 1927-1936页

作者： Aparna Dixit Inas A.Ahmed jisha Annie Abraham Zeinhom M.El-Bahy Mumtaz Manzoor Sajad Ahmad dar Ramesh Sharma Department of Basic Science and Humanities Pranveer Singh Institute of Technology Department of Chemistry Faculty of ScienceKing Khalid University Department of Physics National Defence Academy Department of Chemistry Faculty of ScienceAl-Azhar University Institute of Physics Slovak Academy of Sciences Department of Physics Motilal Vigyan Mahavidyalya College Department of Applied Science Feroze Gandhi Institute of Engineering and Technology

We investigated spinel chalcogenides HgLa2（S/Se）4by using density function theory,and scrutinized the structural,optical,electrical,mechanical and thermoelectric transport characteristics of HgLa2（S/Se）4spinel *** enthalpy of formation,energy of cohesion,and energy volume optimum plots were used to obtain the stability as well as the perfect ground state of these *** ductility of these materials was the best illustrated with the help of Poisson's and Pugh's *** band gap results were obtained using Trans and Blaha modified Becke-johanson potential（TB-mBj）.Both the materials present semi-conducting nature with direct band gap equal to 1.449 and 0.892 eV respectively for HgLa2S4and *** were also made for optical characteristics with the values of dielectric function,absorption coefficient,optical conductivity,reflectivity,and refractive *** to the findings,both of these materials are suitable for infrared optoelectronic *** materials were found to have promising optoelectronic and thermoelectric applications after their optical properties and transport aspects were *** tiny levels of temperature conductivities,substantial am ounts of power conductivities,the figure of merit（more than unity）,as well as Seebecs coefficients all point to the potential use of both the materials in thermoelectric power generators.

关键词： Density functional theory Direct band gap Optoelectronic Power factor Semiconductors Thermoelectric

Optimal vaccination strategies on networks and in metropolitan areas

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Infectious Disease Modelling 2024年第4期9卷 1198-1222页

作者： M.Soledad Aronna lucas Machado Moschen School of Applied Mathematics FGVPraia de Botafogo19022250-900Rio de JaneiroBrazil Laboratory jacques-Louis Lions Sorbonne University

This study presents a mathematical model for optimal vaccination strategies in interconnected metropolitan areas,considering commuting *** is a compartmental model with a vaccination rate for each city,acting as a control *** commuting patterns are incorporated through a weighted adjacency matrix and a parameter that selects day and night *** optimal control problem is formulated to minimize a functional cost that balances the number of hospitalizations and vaccines,including restrictions of a weekly availability cap and an application capacity of vaccines per unit of *** key findings of this work are bounds for the basic reproduction number,particularly in the case of a metropolitan area,and the study of the optimal control *** analysis and numerical simulations provide insights into disease dynamics and the effectiveness of control *** research highlights the importance of prioritizing vaccination in the capital to better control the disease spread,as we depicted in our numerical *** model serves as a tool to improve resource allocation in epidemic control across metropolitan regions.

关键词： Optimal control Epidemiology Vaccination protocols Commuting patterns Metropolitan areas 2000 MSC 92D30 49-11

Variable range hopping transport and dielectric relaxation mechanism in GdCrO_(3) rare-earth orthochromite perovskite

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journal of Rare Earths 2024年第7期42卷 1304-1316,I0004页

作者： Muhammad javed Ayaz Arif Khan jamal Kazmi Naeem Akbar Said Nasir Khisro Amanullah dar Aleem Dad Khan Tareen Mohd Ambri Mohamed Department of Physics The University of Azad Jammu and KashmirMuzaffarabad13100Pakistan Department of Physics University of Kotli Azad Jammu and KashmirKotli11100Pakistan Institute of Microengineering and Nanoelectronics Universiti Kebangsaan Malaysia43600BangiSelangorMalaysia Department of Mathematics University of Kotli Azad Jammu and KashmirKotli11100Pakistan

The polycrystalline GdCrO_(3)(GCO)perovskite orthochromite was synthesized by the sol-gel auto-combustion *** Rietveld refined X-ray diffraction(XRD)profile of GCO confirms that the orthorhombic phase crystallizes in perovskite crystal structure with space group *** transmission electron microscopy and selected area electron diffraction divulge the polycrystalline nature of the perovskite *** field emission scanning electron microscopy(FESEM)images reveal the microstructural polyhedral growth of grains separated by sharp grain *** chemical states of the ions present in the compound were investigated by X-ray photoelectron spectroscopy(XPS)studies,and the electrical pathways were *** impedance studies were carried out in the experimental frequency and temperature ranges of 40 Hz-4 MHz and 178-408 K,*** equivalent circuit model(RGQG)(RGBQGB)resolves the impedance response into two contributions originating from the intra-grain and inter-granular micro-constituents of the *** electrical conduction mechanism is based on the Mott variable range hopping *** complex electric modulus studies demonstrate the short-and long-range mobility of the charge carriers and rule out the presence of electrode effects on the dielectric relaxation mechanism of the *** decreasing pattern of dielectric permittivity with frequency is explained by the Maxwell-Wagner type of *** frequency dependence of the loss factor exhibits the presence of thermally activated relaxation time distribution in the material.

关键词： Auto-combustion Perovskite Electro-ceramic Dielectric Electrical transport Impedance