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Journal of materials Science & Technology 2015年第8期31卷 806-814页

作者： A.Barroso-Bogeat m.alexandre-franco C.Fernndez-Gonzlez V.Gómez-Serrano Department of Organic and Inorganic Chemistry Faculty of SciencesUniversity of Extremadura

In catalysis processes, activated carbon （AC） and metal oxides （mOs） are widely used either as catalysts or as catalyst supports because of their unique properties. A combination of AC and mO nanoparticles in a single hybrid material usually entails both chemical and microstructural changes, which may largely influence the potential catalytic suitability and performance of the resulting product. Here, the prepa- ration of a wide series of AC-mO hybrid catalysts is studied. Three series of such catalysts are prepared by support first of mO （Al2O3, Fe2O3, SnO2, TiO2, WO3, and ZnO） precursors on a granular AC by wet impregnation and oven-drying at 120 ℃, and by subsequent heat treatment at 200 or 850℃ in inert atmosphere. Both the chemical composition and microstructure are mainly investigated by powder X-ray diffraction. Yield and ash content are often strongly dependent on the mO precursor and heat treatment temperature, in particular for the Sn catalysts. With the temperature rise, trends are towards the transformation of metal hydroxides into metal oxides, crystallinity improvement, and occurrence of drastic composition changes, ultimately leading to the formation of metals in elemental state and even metal carbides. Reaction paths during the preparation are explored for various hybrid catalysts and new insights into them are provided.

关键词： Activated carbon metal oxides Hybrid catalysts Preparation microstructural characterization X-ray diffraction

Effect of the Inclusion of Chestnut in the Finishing Diet on Volatile Compounds of Dry-Cured Ham from Celta Pig Breed

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Journal of Integrative Agriculture 2013年第11期12卷 2002-2012页

作者： José m Lorenzo Javier Carballo Daniel franco Centro Tecnológico de la Carne de Galicia Rúa Galicia No 4Parque Tecnológico de GaliciaSan Cibrán das Vias rea de Tecnología de los Alimentos Facultad de Ciencias de OurenseUniversidad de Vigo

The effect of the inclusion of chestnut in pigs ifnishing diet on volatile compounds of dry-cured Celta ham was studied. Twelve hams of each type （from three different pigs ifnishing diets：concentrate （CO）, mixed （mI） and chestnut （CH）） were used. Volatiles were extracted using a purge-and-trap method and analyzed by gas chromatography/mass spectrometry （GC/mS）. Thirty-nine volatile compounds were identified in dry-cured Celta ham samples. most abundant volatiles in ham samples were aldehydes, which represented respectively, 53% （CO）, 51% （mI） and 46% （CH） of the total volatile composition. With the exception of 2-butenal, 2-methyl, all aldehydes were affected by feeding system. On the other hand, hydrocarbons n-alkanes were the second major group in the volatile proifle of dry-cured Celta hams and represented 28.9, 35.7 and 32.4%of the total volatile composition for CO, mI and CH groups, respectively. Ham samples from chestnut group showed a higher content of alcohols and this result could be related with the inclusion of chestnut in the ifnishing diet of pigs. Principal component analysis showed a good separation among groups. The discriminant analysis selected eight variables （butanoic acid, hexanal, octanal, nonenal （E）, decenal （E）, tetradecane, decane trimethyl and pyridine 2-methyl） and calculated two discriminating functions to predict if chestnut has been included in the ifnishing diet. Thus, it was possible to discriminate between groups fed with ifnishing diets containing chestnuts in their composition （mixed and chestnut group）.

关键词： dry-cured ham chestnut volatile compound finishing diet discriminant analysis

Adsorption of methylene Blue on magnesium silicate: Kinetics, equilibria and comparison with other adsorbents

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Journal of Environmental Sciences 2010年第3期22卷 467-473页

作者： franco Ferrero Department of materials Science and Chemical Engineering Polytechnic of Torino Corso Duca degli Abruzzi 24 I10129 Torino Italy

Batch adsorption from aqueous solutions in a slightly basic medium of methylene Blue, up to 2500 mg/L, onto synthetic magnesium silicate （Florisil） of three particle size ranges （mean diameters of 112, 200 and 425 μm） was compared to the corresponding adsorption onto activated carbon and Amberlite XAD-2. The best fit of the kinetic results was achieved by a pseudo second-order equation. The equilibrium data were found to be well represented by the Langmuir isotherm equation. Amberlite XAD-2, an unspecific adsorbent capable of adsorbing exclusively through a surface effect, exhibited a poor dye uptake, confirming that the adsorption mechanism on Florisil was due to electrostatic attraction and ion exchange. moreover, the comparison between Florisil and the other adsorbents was performed on the basis of the evaluation of the surface area and pore volume occupied by the adsorbed dye.

关键词： dye adsorption magnesium silicate Florisil adsorption kinetics adsorption isotherms

Study of fluctuations in the martian magnetosheath using a kurtosis technique:mars Express observations

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Earth and Planetary Physics 2022年第1期6卷 28-41页

作者： A.m.S.franco E.Echer m.J.A.Bolzan m.Fraenz National Institute for Space Research(INPE) Sao Jose dos CamposBrazil Federal University of Jatai JataiBrazil max Planck Institute for Solar System Research GöttingenGermany

Planetary magnetosheaths are characterized by high plasma wave and turbulence *** martian magnetosheath is no exception;both upstream and locally generated plasma waves have been observed in the region between its bow shock and magnetic boundary layer,its induced *** statistical study of wave activity in the martian magnetosheath is based on 12 years(2005-2016)of observations made during mars Express(mEX)crossings of the planet’s magnetosheath-in particular,data on electron density and temperature data collected by the electron spectrometer(ELS)of the plasma analyzer(ASPERA-3)experiment on board the mEX spacecraft.A kurtosis parameter has been calculated for these plasma *** value indicates intermittent behavior in the data when it is higher than 3(the value for a normal or Gaussian distribution).The variation of wave activity occurrence has been analyzed in relation to solar cycle,martian orbit,and distance to the bow ***-Gaussian properties are observed in the magnetosheath of mars on all analyzed scales,especially in those near the proton gyrofrequency in the upstream region of the martian *** also report that non-Gaussian behavior is most prominent at the smaller scales(higher frequencies).A significant influence of the solar cycle was also observed;the kurtosis parameter is higher during declining and solar maximum phases,when the presence of disturbed solar wind conditions,caused by large scale solar wind structures,*** kurtosis decreases with increasing distance from the bow shock,which indicates that the intermittence level is higher near the bow *** the electron temperature data the kurtosis is higher near the perihelion due to the higher incidence of EUV when the planet is closer to the Sun,which causes a more extended exosphere,and consequently increases the wave activity in the magnetosheath and its upstream *** extended exosphere seems to play a lower effect in the electron den

关键词： mars magnetosheath kurtosis ULF waves

A Comparative Study on the Corrosion Behaviour of Hard Anodic Coatings on AA 6061 Obtained Using DC and Pulsed DC Power Sources

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Acta metallurgica Sinica(English Letters) 2013年第6期26卷 647-656页

作者： franco m. Hari Krishna T. Anju m.Pillai A.Rajendra A.K.Sharma Thermal Systems Group ISRO Satellite Centre

The corrosion behaviour of the hard anodic coatings prepared by three different methods viz., conventional hard anodizing （C-HA）, pulse hard anodizing （P-HA） and low voltage room temperature pulse hard anodizing （LVP- HA） on AA 6061 was compared using electrochemical impedance spectroscopy （EIS） and linear polarisation. Scanning electron microscope （SEm） was used to study the surface morphology before and after corrosion. EIS data revealed that no significant difference in corrosion resistance was observed among three types. Rp, Icorr and Ecorr were found to be highly stable over the exposure period up to 72 h which confirms the excellent corrosion resistance. The studies indicate that the corrosion resistance of LVP-HA and P-HA, which are processed at lower voltage and at relatively higher temperatures, are comparable to that of C-HA which is processed at sub-zero temperatures and high operating voltages. The corrosion resistance of all coatings was found to be improved after hydrothermal sealing.

关键词： Aluminium Anodic films EIS Polarisation SEm

SYNTHESIS AND PROPERTIES OF HOmOPOLYmER AND COPOLYmERS OBTAINED FROm 1-OCTADECENE WITH ZIRCONOCENE CATALYSTS

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Chinese Journal of Polymer Science 2000年第3期18卷 249-254页

作者： Raul Quijada Juan L.Guevara Rene Rojas franco m.Rabagliati Departamento de Ingenieria Quimica Facultad de Ciencias Fisicasy MatematicasUniversidad de ChileCasilla 2777SantiagoChile Departamento Ciencias Quimicas Facultad Quimicay BiologiaUniversidad de Santiago de ChileCasilla 40SantiagoChile

Studies related to the behavior of different metallocene catalysts for the homopolymerization of 1-octadecene andits copolymerization with ethylene will be *** metallocenes:rac-Et(Ind)_(2)ZrCl_(2),rac-me_(2)Si(Ind)_(2)ZrCl_(2)andPh_(2)C(Flu)(Cp)ZrCl_(2)were chosen for the homopolymerization *** show important differences in catalytic activity athigh temperatures(≥70℃),with rac-Et(Ind)_(2)ZrCl_(2)showing the highest *** lower temperatures(≤30℃)thedifferences are *** the copolymerization of ethylene with 1-octadecene only the catalysts rac-Et(Ind)_(2)ZrCl_(2)andrac-me_(2)Si(Ind)_(2)ZrCl_(2)were *** results show that their catalytic activity is just like that for the homopolymerizationof 1-octadecene,with higher activity for the metallocene with the Et-bridged catalyst.^(13)C-NmR analysis shows that thecomposition of the copolymerization products depends on the catalytic *** obtained with rac-me_(2)Si(Ind)_(2)ZrCl_(2)have greater comonomer *** analysis shows that poly-1-octadecene synthesized withthe catalyst rac-Et(Ind)_(2)ZrCl_(2)is very dependent on the polymerization *** homopolymer obtained at 70℃presents two endothermal peaks at 41℃and 53℃,as compared with the one obtained at 30℃which presents one wider peakwith a maximum at 67℃.For the catalyst rac-me_(2)Si(Ind)_(2)ZrCl_(2)this trend is not *** type of metallocene and thereaction time do not significantly change the intrinsic viscosity,but the polymerization temperature changes it drastically,giving higher values at lower *** measurements on the copolymers show that an increase of comonomerconcentration in the feed reduces the molecular weight of the copolymer,and it was also found that for homopolymer,themolecular weight is independent of the catalytic systems.

关键词： Homopolymerization Copolymerization metallocene Catalytic activity Poly-l-octadecene

Textures, trace element compositions, and sulfur isotopes of pyrite from the Honghai volcanogenic massive sulfide deposit:Implications for ore genesis and mineral exploration

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Science China Earth Sciences 2023年第4期66卷 738-764页

作者： Zhiyuan SUN Xiaohua DENG franco PIRAJNO School of Resources and Civil Engineering Suzhou UniversitySuzhou 234000China Beijing Institute of Geology for mineral Resources Co. Ltd.Beijing 100012China Key Laboratory of Western China’s mineral Resources and Geological Engineering Ministry of EducationSchool of Earth Science and ResourcesChang’an UniversityXi’an 710054China Centre for Exploration Targeting School of Earth and EnvironmentUniversity of Western AustraliaCrawleyWA 6008Australia

In this paper, we present textures, trace element compositions, and sulfur isotope data for pyrite from the Honghai volcanogenic massive sulfide deposit to place new constraints on the source and evolution of the ore-forming fluids and provide insights into the ore genesis with implications for future exploration. The Honghai deposit consists of upper lenticular ores comprising massive sulfides that are underlain by stockwork and disseminated sulfides. The textural and isotopic characteristics of the synsedimentary framboidal pyrite(Syn-Py) indicate its formation by biogenetic processes. Coarse-grained pyrite generations(m-Py1, m-Py2, and m-Py3) from the massive sulfides have high Au, Ag, Cu, Zn, Pb, Sb, and Tl concentrations and low Co, Se, Te, Ti, and Sn concentrations, indicating that they precipitated from metal-rich, low-to intermediate-temperature,oxidizing fluids. The high Te, Ti, and Sn concentrations and high Co/Ni ratios in the massive pyrite(m-Py4) associated with magnetite in the massive sulfide lenses, as well as the high Ti, V, Cr, and Ni concentrations and low Al, mn, and Zn concentrations in the magnetite, suggest that the coexisting m-Py4 and magnetite precipitated under oxidizing and hightemperature(300℃ to 500℃) conditions. In contrast, pyrite grains from the underlying stockwork and veins(V-Py1, V-Py2, and V-Py3) are characterized by low Au, Ag, Cu, Zn, Pb, Sb, and Tl concentrations coupled with high Co, Se, Te, and Ti concentrations and high Co/Ni ratios, which are interpreted in terms of reducing and high-temperature ore-forming fluids. The large variations in δ^(34)S values from-6.4‰ to +29.9‰ suggest that the ore-forming fluids were derived from magmatic source that were significantly modified by seawater. The spatial variations of trace element assemblages of pyrite from different levels of the main massive orebodies can be used as an indicator for mineral exploration of Cu-Zn ores in the Honghai *** no significant difference in

关键词： Pyrite Trace element compositions Sulfur isotopes Ore-forming fluids Honghai volcanogenic massive sulfide deposit

Raman probing carbon&aqueous electrolytes interfaces and molecular dynamics simulations towards understanding electrochemical properties under polarization conditions in supercapacitors

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Journal of Energy Chemistry 2021年第9期30卷 279-292页

作者： Rafael Vicentini Leonardo m.Da Silva Débora V.franco Willian G.Nunes Juliane Fiates Gustavo Doubek Luís F.m.franco Renato G.Freitas Cristiano Fantini Hudson Zanin Advanced Energy Storage Division Carbon Sci-Tech LabsUniversity of CampinasAv Albert Einstein 400CampinasSP 13083-852Brazil Department of Chemistry Federal University of Jequitinhonha and Mucuri’s ValleyRodovia MGT 367km 5835000Alto da Jacuba39.100-000 DiamantinaMGBrazil Advanced Energy Storage Division Center for Innovation on New EnergiesLaboratory of Advanced BatteriesSchool of Chemical EngineeringUniversity of Campinas(UNICAMP)CampinasSP 13083-852Brazil Department of Chemistry Federal University of Mato GrossoICET-UFMT78060-900 CuiabáMTBrazil Departamento de Física ICExUniversidade Federal de Minas GeraisBelo HorizonteMG 31270-901Brazil

Raman probing of carbon electrode and electrolyte under dynamic conditions is performed here using different aqueous electrolytes to elucidate the fundamental events occurring in electrochemical supercapacitor during charge–discharge *** areal capacitance ranges from 1.54 to 2.31μF cm^(-2)μm and it is determined using different *** findings indicate that the Helmholtz capacitance governs the overall charge-storage process instead of the space charge(quantum)capacitance commonly verified for HOPG electrodes in the range of~3 to 7μF cm^(-2).molecular dynamics simulations are employed to elucidate the origin of the reversible Raman spectral changes during the charge–discharge processes.A correlation is verified between the reversible Raman shift and the surface excesses of the different ionic species.A theoretical framework is presented to relate the effect of the applied potential on the Raman shift and its correlation with the surface ionic *** is proposed that the Raman shift is governed by the interaction of solvated cations with graphite promoted by polarization *** is the first time that a comparative study on different aqueous electrolyte p H and cation ion size has been performed tracking the Raman spectra change under dynamic polarization conditions and contrasting with comprehensive electrochemistry and dynamic molecular simulations *** study shines lights onto the charge-storage mechanism with evidence of Kohn anomaly reduction in the carbon electrode during the reversible adsorption/desorption and insertion/extraction of ionic species.

关键词： Defect reorganization in graphite Surface excess of charge Operando Raman studies Electrical double-layer capacitors

Serendipity Virtual Elements for General Elliptic Equations in Three Dimensions

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Chinese Annals of mathematics,Series B 2018年第2期39卷 315-334页

作者： Lourenco BEIRAO DA VEIGA franco BREZZI franco DASSI Luisa Donatelia mARINI Alessandro RUSSO Dedicated to Philippe G. Ciarlet on the occasion of his 80th birthda

The authors study the use of the virtual element method(VEm for short) of order k for general second order elliptic problems with variable coefficients in three space dimensions. moreover, they investigate numerically... 详细信息

关键词： Virtual element methods Polyhedral decompositions Linear ellipticproblems Serendipity

Effect of successive sprays on liquid distribution in fluidized beds

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Particuology 2021年第1期19卷 17-24页

作者： Cedric Briens Liliana Pardo Reyes franco Berruti Jennifer mcmillan Institute for Chemicals and Fuels from Alternative Resources Western University22312 Wonderland Rd.IldertonONN0M 2A0Canada Edmonton Research Centre Syncrude Canada Ltd942117th AveEdmontonABT6N 1H4 Canada

In processes such as Fluid Coking^(™),agglomerate formation should be minimized since it reduces the yield of valuable products,and degrades operability because of the fouling of *** experimental model,consisting of an aqueous solution of gum arabic with a dye,has been successfully developed to simulate the formation of agglomerates in the Fluid Coking^(™)process,where bitumen is sprayed into a fluidized bed of coke particles The particles wetted by a spray could be predicted by assuming that all the particles in the wake of bubbles formed from the tip of the spray jet have been wetted by the injected *** transfer of liquid from particles wetted with the spray to dry bed particles was relatively ineffective,as the number of wet particles increased by only 50%.With successive liquid injections,the proportion of the liquid trapped in agglomerates increases in latter injections:large agglomerates from earlier injections accumulate above the grid and are carried by gas bubbles into the spray jet cavity,where they seed fresh agglomerates.

关键词： Fluidized bed Liquid injection Agglomerate formation Fluid Coker