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Chinese journal of Chemical Engineering 2018年第4期26卷 812-821页

作者： Hugo i.Velázquez-Sánchez Ricardo Aguilar-lópez Center of Research and Advances Studies of the National Polytechnic institute (CiNVESTAV) Biotechnology and Bioengineering DepartmentAv. National Polytechnic Institute 2508 Col. San Pedro Zacatenco

Acetone–butanol–ethanol(ABE)fermentation process can be exploited for the generation of butanol as biofuel,however it does need to overcome its low volumetric solvent productivity before it can commercially compete with fossil fuel *** this regard,mathematical modelling and simulation analysis are tools that can serve as the base for process engineering development of biological *** this work,a novel phenomenological kinetic model of Clostridium acetobutylicum ATCC 824 was considered as a benchmark system to evaluate the behaviour of an ABE fermentation under different process configurations using both free and immobilized cells:single stage batch operation,fed-batch,single stage Continuous Stirred Tank Reactor(CSTR)and multistage CSTRs with and without biomass *** proposed model achieved a linear correlation index r^2=0.9952 and r^2=0.9710 over experimental data for free and immobilized cells *** predicted maximum butanol concentration and productivity obtained were 13.08 g·l^(-1)and 1.9620 g·l^(-1)·h^(-1)respectively,which represents an increase of 1.01%and 990%versus the currently developed industrial scale process reported currently into the *** results provide a reliable platform for the design and optimization of the ABE fermentation system and showcase the adequate predictive nature of the proposed model.

关键词： Biofuels Butanol Clostridium acetobutylicum Mathematical modelling Process configurations

Structural evolution, optoelectrical and corrosion properties of electrodeposited WO_3 integration on Zn-TiO_2 electrolyte for defence super application

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Defence Technology（防务技术） 2018年第5期14卷 396-402页

作者： A.A.Daniyan l.E.Umoru O.S.i.Fayomi A.P.i.Popoola Department of Materials Science and Engineering Obafemi Awolowo University Department of Chemical Metallurgical and Materials Engineering Tshwane University of Technology Department of Mechanical Engineering Covenant University

Multifunctional nano composite coatings of Zn-TiO_2-WO_3 were deposited electrolytically on mild steel(MS) from Zn bath, having Zn^(2+) ions and uniform dispersion of TiO_2 and WO_3 nano particulates. The electrical, optical and corrosion resistance characteristics of the electrocodeposited coatings were assessed by Keithley 2400 Series Source meter with Multimeters, Newport Solar Simulator and a PGSTAT30 Autolab potentiostat respectively. The morphological characteristics of the composite coatings were characterized by scanning electron microscope(SEM) equipped with energy dispersive spectrometer(EDS). The result revealed that the electrocodeposits showed good stability and Zn-TiO_2-WO_3 nanocomposite deposits displayed enhanced microstructural qualities, good electrical conductivity and exhibited enriched corrosion resistance.

关键词： Nano-composite Electrocodeposition Corrosion Conductivity and resistance

Convective flow of jeffrey nanofluid along an upright microchannel with Hall current and Buongiorno model:an irreversibility analysis

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Applied Mathematics and Mechanics(English Edition) 2023年第9期44卷 1613-1628页

作者： l.ANiTHA B.j.GiREESHA Department of PG Studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451India Department of Mathematics Adichunchanagiri Institute of TechnologyChikkamagaluru 577102India

The thermal properties and irreversibility of the jeffrey nanofluid through an upright permeable microchannel are analyzed by means of the Buongiorno *** effects of the Hall current,exponential space coefficient,nonlinear radiation,and convective and slip boundary conditions on the jeffrey fluid flow are explored by deliberating the buoyant force and viscous *** non-dimensionalized equations are obtained by employing a non-dimensional system,and are further resolved by utilizing the shooting approach and the 4th-and 5th-order Runge-Kutta-Fehlberg *** obtained upshots conclude that the amplified Hall parameter will enhance the secondary flow *** improvement in the temperature parameter directly affects the thermal profile,and hence the thermal field declines.A comparative analysis of the Newtonian fluid and non-Newtonian fluid(jeffrey fluid)is carried out with the flow across a porous *** the Bejan number,thermal field,and entropy generation,the jeffrey nanofluid is more highly supported than the Newtonian fluid.

关键词： jeffrey nanofluid entropy generation exponential heat source porous medium convective and slip boundary condition

Repercussion of Hall effect and nonlinear radiation on Couette-Poiseuille flow of Casson-Williamson fluid through upright microchannel

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Applied Mathematics and Mechanics(English Edition) 2022年第12期43卷 1951-1964页

作者： B.j.GiREESHA l.ANiTHA Department of Post Graduation Studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451India Department of Mathematics Adichunchanagiri Institute of TechnologyChikkamagaluru 577102India

The main aim of the present work is to investigate the flow and heat transport properties of non-Newtonian Casson-Williamson fluid through an upright microchannel along with entropy generation analysis,and explore the effects of convective boundary conditions,Couette-Poiseuille flow,and nonlinear *** movement of liquid is scrutinized with the Hall effect and exponential heat *** rheological characteristics of the Casson-Williamson fluid model are also *** considering the desirable similarity variables,the equations of motion are reduced to nonlinear ordinary differential *** Runge-Kutta-Fehlberg fourth-fifth order method along with the shooting method is adopted to solve these dimensionless *** detailed investigation is pictorially displayed to show the influence of effective parameters on the entropy generation and the Bejan *** of the major tasks of the exploration is to compare the Casson fluid and the Williamson *** results show that the rate of heat transfer in the Casson fluid is more remarkable than that in the Williamson fluid.

关键词： entropy generation Bejan number convective boundary condition Hall effect nonlinear radiation exponential heat source

Effect of relative humidity on the metabolite profiles,antioxidant activity and sensory acceptance of black garlic processing

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Food Bioscience 2022年第4期48卷 559-567页

作者： P.j.Gonzalez-Ramírez l.i.Pascual-Mathey R.V.García-Rodríguez ,M.jimenez C.i.Beristain A.Sanchez-Medina l.A.Pascual-Pineda instituto de Química Aplicada Universidad VeracruzanaAv.Dr.Luis Castelazo Ayala s/nCol.Industrial-AnimasC.P.91190XalapaVeracruzMexico Facultad de Química Farmaceutica Biologica Universidad VeracruzanaXalapaVeracruzMexico Centro de investigacion y Desarrollo en Alimentos(CiDEA) Universidad VeracruzanaXalapaVeracruz91190Mexico

Fresh garlic(FG)was processed at five different relative humidities(RH)at 55◦C for 40 *** moisture content,aw,browning intensity and DPPH scavenging capacity were determined during processing under controlled *** processing,sensory acceptance and metabolite differences were analyzed using ***,a chemometric analysis was performed using both the 1H-NMR chemical profiles and the sensory evaluation of the 40-day black garlic(BG)*** increase in the antioxidant capacity at higher browning rate was *** variability for twenty-five compounds showed main changes in amino and organic acids,sugars,organosulfur compounds,ethanol,methanol GABA,choline and *** acceptance values on the sensory evaluation were for BG processed at 58 and 71%RH,indicating that intermediates RH results in a better sensory *** OPlS-DA chemometric analysis showed that sugars,formic acid,5-HMF,amino acids,ethanol,and choline were the main contributors.

关键词： Black garlic processing Antioxidant activity Chemical profile Sensory evaluation Chemometrics OPlS

Shielding AZ91D-1%Ca from corrosion through ultrasound melt treatment:A study for stent design

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journal of Magnesium and Alloys 2023年第8期11卷 2901-2915页

作者： i.V.Gomes M.Pacheco M.Nienaber S.C.Neves D.Mei A.Barros R.l.Reis j.l.Alves H.Puga CMEMS–UMinho University of MinhoGuimarãesPortugal lABBElS–Associate laboratory BragaGuimarãesPortugal B's Research Group-Research institute on Biomaterials Biodegradables and BiomimeticsUniversity of MinhoHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineAvepark-Parque de Ciência e TecnologiaBarco GuimarãesPortugal iCVS/3B's-PT Government Associate laboratory BragaGuimarãesPortugal institute of Material and Process Design Helmholtz-Zentrum HereonGeesthacht 21502Germany School of Materials Science and Engineering&Henan Key laboratory of Advanced Magnesium Alloy Zhengzhou UniversityZhengzhou 450001China

Magnesium-based materials show great potential for producing biodegradable stents,but their high corrosion rates are a *** study investigates whether ultrasound melt treatment can change the corrosion response of an extruded AZ91D-1.0%Ca(wt.%)in Earle's Balanced Salt Solution by tailoring the intermetallics'morphology in the as-extruded *** results showed that the wires from ultrasound-treated ingots corroded faster than non-treated ones in immersion for up to 6 *** trend shifted for longer periods,and ultrasound-treated material showed lower corrosion rates and uniform corrosion,while the non-treated material displayed localized corrosion *** testing of the wires demonstrated that immersion in EBSS lowered the tensile strength and elongation at fracture due to material degradation,regardless of the processing ***,this decline was sharper in the non-treated *** findings suggest that ultrasound melt processing can be a promising method for improving the corrosion resistance of magnesium-based materials,paving the way for their use in manufacturing biodegradable stents.

关键词： Magnesium Ultrasound treatment Stent Corrosion Mechanical properties

Simultaneous Preservation of Soil Structural Properties and Phospholipid Profiles: A Comparison of Three Drying Techniques

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Pedosphere 2008年第3期18卷 284-287页

作者： l. j. DEACON D. V. GRiNEV j. W. CRAWFORD j. HARRiS K. RiTZ i. M. YOUNG National Soil Resources institute Department of Natural Resources School of Applied Sciences Cranfield University Cranfield MK43 0AL (UK) SiMBiOS Centre University of Abertay Dundee DD1 1HG (UK) integrated Earth Systems Science institute Department of Natural Resources School of Applied Sciences Cranfield University Cranfield MK43 0AL (UK)

There is a need to simultaneously preserve evidence of interactions between the biological community and soil structural properties of a soil in as near an intact （natural） state as possible. Three dehydration techniques were implemented and assessed for their ability to minimise disruption of both biological and physical properties of the same arable soil sample. Dehydration techniques applied until samples were at constant weight were i） air-drying at 20℃ （AD）; ii） -80 ℃ freeze for 24 h, followed by freeze-drying （-80FD）; and iii） liquid nitrogen snap freeze, followed by freeze-drying （lNPD） and were compared to a moist control. Physical structure was determined and quantified in three dimensions using X-ray computed tomography and microbial phenotypic community composition was assessed using phospholipid fatty acid （PlPA） profiling. This study confirms that any form of dehydration, when preparing soil for simultaneous biological and physical analysis, will alter the soil physical properties, and cause some change in apparent community structure. Freeze-drying （both the lNFD and -80FD treatments） was found to minimise disruption （when compared to the moist control soil） to both the soil physical properties and the community structure and is a preferable technique to air-drying which markedly alters the size and character of the pore network, as well as the phenotypic profile. The lNFD was the preferred treatment over the -80FD treatment as samples show low variability between replicates and a fast turn-around time between samples. Therefore snap freezing in liquid nitrogen, followed by freeze drying is the most appropriate form of dehydration when two sets of data, both physical and biological, need to be preserved simultaneously from a soil core.

关键词： biological community dehydration phospholipid profile physical properties preservation

Corrosion protection of AZ91D magnesium alloy by a cerium-molybdenum coating-The effect of citric acid as an additive

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journal of Magnesium and Alloys 2018年第4期6卷 356-365页

作者： i.l.lehr S.B.Saidman instituto de ingeniería Electroquímica y Corrosión(iNiEC) Departamento de Ingeniería QuímicaUniversidad Nacional del Sur(UNS)CONICETBahía BlancaArgentina

in order to improve the corrosion resistance of AZ91D magnesium alloy,a coating was formed by a potentiostatic technique from a solutions containing Ce(NO_(3))_(3),Na_(2)MoO_(4)and citric acid(H_(3)Cit).The degree of corrosion protection achieved was evaluated in simulated physiological solution by monitoring the open circuit potential,polarization techniques and electrochemical impedance spectroscopy(EiS).Surface analysis techniques(SEM,EDS,X-ray diffraction and X-ray photoelectron spectroscopy(XPS))were used for coating *** film is mainly composed by cerium and molybdenum oxides and magnesium oxides and *** obtained results show that the corrosion resistance of the coated electrodes has been increased *** improvement in the anticorrosive performance is in part due to the corrosion inhibition properties of H_(3)Cit.

关键词： Cerium and molybdenum-based coatings AZ91D alloy Citric acid Anticorrosive properties

Tree wave migration across an elevation gradient in the Altai Mountains,Siberia

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journal of Mountain Science 2017年第3期14卷 442-452页

作者： Viacheslav i.KHARUK Sergei T.iM Maria l.DViNSKAYA Kenneth j.RANSON il'ya A.PETROV Sukachev institute of Forest SB RAS KrasnoyarskRussia Siberian Federal University KrasnoyarskRussia M.F.Reshetnev Siberian State Aerospace University KrasnoyarskRussia NASA's Goddard Space Flight Center GreenbeltMarylandUSA

The phenomenon of tree waves （hedges and ribbons） formation within the alpine ecotone in Altai Mountains and its response to observed air temperature increase was considered. At the upper limit of tree growth Siberian pine （Pinus sibirica） forms hedges on windward slopes and ribbons on the leeward ones. Hedges were formed by prevailing winds and oriented along winds direction. Ribbons were formed by snow blowing and accumulating on the leeward slope and perpendicular to the prevailing winds, as well as to the elevation gradient. Hedges were always linked with microtopography features, whereas ribbons were not. Trees are migrating upward by waves and new ribbons and hedges are forming at or near tree line, whereas at lower elevations ribbons and hedges are being transformed into dosed forests. Time series of high-resolution satellite scenes （from 1968 to 2OlO） indicated an upslope shift in the position ribbons averaged 155＋26 m （or 3-7 m yr^-1） and crown closure increased （about 35%-90%）. The hedges advance was limited by poor regeneration establishment and was negligible. Regeneration within the ribbon zone was approximately 2.5 times （5060 vs 2120 ha^-1） higher then within the hedges zone. During the last four decades, Siberian pine in both hedges and ribbons strongly increased its growth increment, and recent tree growth rate for 50 year-old trees was about twice higher than those recorded for similarly-aged trees at the beginning of the 20^th century. Hedges and ribbons are phenomena that are widespread within the southern and northern Siberian Mountains.

关键词： Ribbon forest Hedges Siberian forests Alpine treeline Tree waves Siberian pine AltaiMountains

isothermal hydrogen absorption process of Pd-capped Mg films traced by ion beam techniques and optical methods

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journal of Magnesium and Alloys 2024年第9期12卷 3675-3684页

作者： D.Abejón P.Prieto j.K.Kim A.Redondo-Cubero M.l.Crespillo F.leardini i.j.Ferrer G.García j.R.Ares Departamento de Fisica de Materiales Universidad Autónoma de MadridMadrid28049Spain Centro de Micro-Análisis de Materiales(CMAM) Universidad Autónoma de MadridMadrid28049Spain Advanced Analysis Center KIST5 Hwarang-ro 14-gilSeoul 02792Republic of Korea Departamento de Física Aplicada Universidad Autónoma de MadridMadrid28049Spain instituto Nicolás Cabrera Universidad Autónoma de MadridMadrid28049Spain

Pd-capped nanocrystalline Mg films were prepared by electron beam evaporation and hydrogenated under isothermal conditions to inves-tigate the hydrogen absorption process via ion beam techniques and in situ optical *** were characterized by different techniques such as X-ray diffraction(XRD)and scanning electron microscopy(SEM).Rutherford backscattering spectrometry(RBS)and elastic recoil detection analysis(ERDA)provided a detailed compositional depth profile of the films during ***-solid reaction kinetics theory applied to ERDA data revealed a H absorption mechanism controlled by H *** rate-limiting step was also confirmed by XRD *** diffusion coefficient(D)was also determined via RBS and ERDA,with a value of(1.1±0.1)·10^(−13)cm^(2)/s at 140℃.Results confirm the validity of iBA to monitor the hydrogenation process and to extract the control mechanism of the *** H kinetic information given by optical methods is strongly influenced by the optical absorption of the magnesium layer,revealing that thinner films are needed to extract further and reliable information from that technique.

关键词： Magnesium hydride Hydrogen absorption ion beam techniques Optical tracing Absorption mechanism