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MgO-based adsorbents for CO2 adsorption:Influence of structural and textural properties on the CO_2 adsorption performance

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Journal of Environmental Sciences 2017年第7期29卷 418-428页

作者： gutiérrez-Bonilla Elvira Granados-Correa Francisco Sánchez-Mendieta víctor Morales-Luckie Raúl Alberto National Institute of Nuclear Research Department of ChemistryA.P.18-1027Col.EscandonMigud Hidalgo DelegationZip Code 1180 Mexico D.F.Mexico Autonomous University of Mexieo State Faculty of ChemistryColon avenueintersection with ride Tollocan s/n TolucaMexicoMexico

A series of MgO-based adsorbents were prepared through solution–combustion synthesis and ball-milling *** prepared MgO-based powders were characterized using X-ray diffraction,scanning electron microscopy,N_2 physisorption measurements,and employed as potential adsorbents for CO_2 *** influence of structural and textural properties of these adsorbents over the CO_2 adsorption behaviour was also *** results showed that MgO-based products prepared by solution–combustion and ball-milling processes,were highly porous,fluffy,nanocrystalline structures in nature,which are unique physico-chemical properties that significantly contribute to enhance their CO_2 *** was found that the MgO synthesized by solution combustion process,using a molar ratio of urea to magnesium nitrate（2：1）,and treated by ball-milling during 2.5 hr（MgO-BM2.5h）,exhibited the maximum CO_2 adsorption capacity of 1.611 mmol/g at 25℃ and 1 atm,mainly via *** CO_2 adsorption behaviour on the MgO-based adsorbents was correlated to their improved specific surface area,total pore volume,pore size distribution and *** reusability of synthesized MgO-BM2.5h was confirmed by five consecutive CO_2adsorption–desorption times,without any significant loss of performance,that supports the potential of MgO-based *** results confirmed that the special features of MgO prepared by solution–combustion and treated by ball-milling during 2.5 hr are favorable to be used as effective MgO-based adsorbent in post-combustion CO_2 capture technologies.

关键词： CO_2 adsorption MgO-based adsorbents porous materials Solution–combustion synthesis Ball-milling process Textural properties

Single atom Cu-N-C catalysts for the electro-reduction of CO_(2) to CO assessed by rotating ring-disc electrode

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Journal of Energy Chemistry 2024年第1期88卷 169-182,I0004页

作者： S.pérez-Rodríguez M.gutiérrez-Roa C.Giménez-Rubio D.Ríos-Ruiz p.Arévalo-Cid M.v.Martínez-huerta A.Zitolo M.J.Lázaro D.Sebastián Instituto de Carboquímica(CSIC) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de Catálisis y petroleoquímica(CSIC) Marie Curie 228049 MadridSpain Synchrotron SOLEIL L’Orme des MerisiersDépartementale 12891190France

The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic performance of Cu-N-C materials is assessed by a rotating ring-disc electrode(RRDE), technique still rarely explored for CO_(2)RR. For comparison, products are also characterized by online gas chromatography in a h-cell. The as-synthesized Cu-NC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 v ***) in 0.1 M KhCO_(3), while h_(2) from the competitive water reduction appears at larger overpotentials(-0.9 v vs. RhE). The optimum copper acetate-derived catalyst containing Cu-N_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 v vs. RhE with a h_(2)/CO ratio of 1.8. These results demonstrate that RRDE configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)RR.

关键词： Cu-N-C Carbon xerogel Rotating ring disc electrode Carbon dioxide reduction reaction Carbon monoxide

Selection and Analysis of polymorphisms in Somaclonal variants of Agave americana Resistant to Fusarium oxysporum via an Ethyl Methanesulphonate Treatment

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phyton-International Journal of Experimental Botany 2021年第6期90卷 1727-1739页

作者： Sheila Jazmín Reyes-Zambrano Carlos Alberto Lecona-Guzmán Federico Antonio gutiérrez-Miceli víctor Manuel Ruiz-valdiviezo Arely Anayansi vargas-Díaz Laboratorio de Biotecnología vegetal Instituto Tecnológico de Tuxtla GutiérrezTecnológico Nacional de MéxicoTuxtla GutiérrezChiapas29050México CONACYT-Colegio de postgraduados Campus Campeche ChampotónCampeche24450México

Agave americana *** were exposed to different concentrations of ethyl methanesulphonate(EMS)0,15,30,45 and 60 mM and to different times of exposure(2 and 4 h).The viability and capacity of shoot formation were shown to be affected when the callus were exposed to high concentrations(30–60 mM).Only the callus exposed to 15 mM EMS presented shoot formation;the exposure time of two hours produced the largest quantity of shoots regenerated per callus(21 shoots/callus).In order to generate somaclonal variants resistant to Fusarium oxysporum,a selection pressure was applied through of a culture filtrate(CF)of 100 ppm of the *** was made in callus obtained in the treatment with 15 mM EMS during 2 h of *** CF caused oxidation and necrosis in 71.25%of the callus;however,they were capable of generating shoots(3.5 shoots/callus).Molecular markers type RApD,ISSR and DAMD were used to evaluate the genetic variation arising from the mutations caused by EMS on control plants and 16-month-old somaclonal *** polymorphic information content(pIC)for each one of the initiating groups was:0.28(DAMD),0.09(ISSR)and 0.14(RApD).DAMD revealed a greater percentage of polymorphism than RApD and *** bands were detected in the somaclonal *** indicated that the EMS caused genetic variation in the regenerated plants conferring resistance to them against Fusarium oxysporum.

关键词： Mutagenesis polymorphisms genetic variation molecular markers

Steroid hyperglycemia: prevalence, early detection and therapeutic recommendations: A narrative review

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World Journal of Diabetes 2015年第8期6卷 1073-1081页

作者： héctor Eloy Tamez-pérez Dania Lizet Quintanilla-Flores René Rodríguez-gutiérrez José Gerardo González-González Alejandra Lorena Tamez-pena Internal Medicine Service “Dr.José Eleuterio González”University Hospital and School of MedicineUniversidad Autónoma de Nuevo León Research Division School of MedicineUniversidad Autónoma de Nuevo León Endocrinology Service “Dr.José Eleuterio González”University Hospital and School of MedicineUniversidad Autónoma de Nuevo León

Steroids are drugs that have been used extensively in a variety of conditions. Although widely prescribed for their anti-inflammatory and immunosuppressive properties, glucocorticoids have several side effects, being hyperglycemia one of the most common and representative. In the present review, we discuss the main epidemiologic characteristics associated with steroid use, with emphasis on the identification of high risk populations. Additionally we present the pathophysiology of corticosteroid induced hyperglycemia as well as the pharmacokinetics and pharmacodynamics associated with steroid use. We propose a treatment strategy based on previous reports and the understanding of the mechanism of action of both, the different types of glucocorticoids and the treatment options, in both the ambulatory and the hospital setting. Finally, we present some of the recent scientific advances as well as some options for future use of glucocorticoids.

关键词： Steroid hyperglycemia Diabetes mellitus Treatment Insulin

Spin States of 2D Nanocomposites of Ni and v Nanoclusters on hexagonal h-BN, BC_3 and Graphene

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Journal of Materials Science & Technology 2015年第10期31卷 979-985页

作者： p.Avramov A.A.Kuzubov S.Sakai S.Entani h.Naramoto N.Eliseeva Kyungpook National University Siberian Federal University L.v.Kirensky Institute of physics SB RAS Advanced Science Research Center Japan Atomic Energy Agency

Atomic and electronic structures of adsorbed nickel and vanadium atoms and nanoclusters （Nin and vn, n = 1-10） on hexagonal h-BN and BC3 lattices were studied using DFT pBE/pBC/pW （perdew-Burke- Ernzerhof potential of density functional theory/periodic boundary conditions/plane wave basis set） technique. For the sake of comparison the structure and properties of the same nanoclusters deposited on pristine graphene were calculated as well. It was found that for all types of supports an increase of n from 1 to 10 leaded to decrease of coordination types from 776 to r/2 and 771. The h-BN- and BC3-based nanocomposites were characterized by high （up to 18 μ for Ni10/BC3） magnetic moments of the nanoclusters and featured by positive binding energies. The graphene-based nanocomposites revealed energetic stability and, in general, lower magnetic moments per unit cell. The direct potential energy barriers for migration of Ni η2/η21 and η6/η6 types of dimers on graphene were low （10.9-28.9 kJ/mol） with high reverse barriers for η6/η6 dimers, which favored dynamically equilibrated Ni clusterization on graphene.

关键词： Electronic structureMetal nanostructure Nanocomposites Grapheneh-BNBC3 Spin states

Evaluating methods to quantify sediment volumes trapped behind check dams,Saldana badlands(Spain)

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International Journal of Sediment Research 2017年第1期32卷 1-11页

作者： Iván Ramos-Diez Joaquín Navarro-hevia Roberto San Martín Fernández virginia Díaz-gutiérrez Jorge Mongil-Manso Department of Agricultural and Forestry Engineering University of Valladolid Sustainable Forest Management Research Institute Department of Statistics and Operations Research.University of valladolid hydrology and Conservation Research Group.Catholic University of vila

The determination of sediment yield in catchments based on the sediment trapped by check dams is becoming a subject of *** fact,several methods have been developed in recent years to estimate the sediment retained by check *** complexity,precision and accuracy of each method vary *** this study,we evaluate the sediment trapped by check dams comparing the Sections method respect to the prism,pyramid,DTMs and Trapezoid *** analyzed a sample of 25 check dams(α-1=90%;ε=10%) in the Saldana badlands(Spain).The results showed that the Sections method offered a volume of retained sediment between the others,which gave an absolute variation from 22%to40%.The high variability of the check dam and sediment wedge sizes made necessary to compare methods in groups combining both *** significant differences in sediment volumes could be found between the methods for very small(height(h):1.8-2.3 m;trapped volume(v):6-102 m3) or large check dams(h > 2.3 m;v:165-387 m3),while significant differences are found for small(h v:1-229 m3) or middle-sized check dams(h:2.2-3.2 m;v:65-235 m3).Nevertheless,volume differences between groups ranged up to + 25%.For these reason,the size of the check dam,the shape of the sediment wedge and the accuracy of the measure methods must considered when selecting an appropriate method to obtain the volume of retained sediment by check dams.A correct estimation of the sediment retention is needed to evaluate the role and efficiency of check dams in restoration projects or to estimate sediment yields.

关键词： Erosion Gullies Check dam construction Sediment retention Erosion models Topographic survey

Energy conditions of the f(T,B) gravity dark energy model with the validity of thermodynamics

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Communications in Theoretical physics 2020年第8期72卷 109-118页

作者： S h Shekh v R Chirde p K Sahoo Department of Mathematics S.P.M.Science and Gilani Arts and Commerce CollegeGhatanjiYavatmalMaharashtra-445301India Department of Mathematics G.S.G.MahavidyalayaUmarkhed-445206India Department of Mathematics Birla Institute of Technology and Science-PilaniHyderabad CampusHyderabad-500078India

In this article, the analysis of Tsallis holographic dark energy(which turns into holographic dark energy for a particular choice of positive non-additivity parameter δ) in modified f(T, B) gravity with the validity of thermodynamics and energy conditions for a homogeneous and isotropic FLRW Universe has been studied. The enlightenment of the field equation towards f(T,B)=αT^m+βB^n, made possible by the fact that the model is purely accelerating,corresponds to q=-0.54(Mamon and Das 2017 Eur. phys.J.C 77 49). The generalized second law of thermodynamics is valid not only for the same temperature inside the horizon, but also for the apparent horizon for a change in temperature. The essential inspiration driving this article is to exhibit the applicability that the holographic dark energy achieved from standard Tsallis holographic dark energy and the components acquired from f(T, B) gravity are identical for the specific bounty of constants. The analysis of energy conditions confirms that the weak energy condition and the null energy condition are fulfilled throughout the expansion, while violation of the strong energy condition validates the accelerated expansion of the *** the expansion, the model becomes a quintessence dominated model. The dominant energy condition is not observed initially when the model is filled with genuine baryonic matter,whereas it appears when the model is in the quintessence dominated era.

关键词： Tsallis holographic dark energy f(T B)gravity energy conditions thermodynamics

In vitro-propagation of Agave tequilana Weber *** in a Temporary Immersion System

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phyton-International Journal of Experimental Botany 2022年第1期91卷 83-96页

作者： Otilio vázquez-Martínez héctor Gordon Núñez-palenius Eugenio M.pérez-Molphe Balch Mauricio valencia-posadas Luis pérez-Moreno Graciela M.L.Ruiz-Aguilar M.Gómez-Lim División de Ciencias de la vida Universidad de GuanajuatoIrapuato36500México Departamento de Química Centro de Ciencias BásicasUniversidad Autónoma de AguascalientesAguascalientes20131México Departamento de Ingeniería Genética CINVESTAV Unidad IrapuatoIrapuato36500México

In Mexico,there is a need to produce large quantities of plantlets for the establishment and replanting of blue(***)agave production *** of these plots are within the origin denomination area(DOT,Spanish acronym)of the distilled product of this plant,known as *** objective of this study was to develop an in vitropropagation protocol for Agave tequilana Weber *** using segmented stems in both:solid and liquid media.A disinfection and in vitro technique were developed to obtain shoots,through plantlets collected in commercial plots,which attained 100%surface-disinfection and budding *** the multiplication stage,the effects of 6-Benzylaminopurine(BA)(0.0,4.4 and 13.2μM)and kinetin(0.0,9.4,18.8 and 37.6μM)were evaluated on lateralshoot production of segmented sagittal *** were cultivated on Murashige&Skoog(MS)medium,with the addition of 3.0%sucrose and 8 g L−1 *** was observed that BA and kinetin increased the number of shoots per explant,obtaining up to 18 and 26,***,it was found that just the sagittal segmentation of explants increased axillary *** the other hand,segmented-stem bases were grown in MS liquid medium with 3.0%sucrose,inside a RITAsystem,programmed by a 5 min immersion step with a frequency of every 4 *** effect of Indole−3-Acetic acid(IAA)(0.57,2.9,5.7μM)was evaluated,while maintaining a concentration of BA(13.2μM).It was observed that the greatest concentration of IAA led to the formation of more than 20 buds per *** results offer a new methodology to increase the efficiency of *** Weber ***-in vitro multiplication by sagittal segmentation of stems and the addition of BA and/or IAA.

关键词： plant tissue culture stem-disk culture tequila in vitro culture

Analysis of Internal Cooling Geometry variations in Gas Turbine Blades

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Journal of Thermal Science 2009年第4期18卷 289-293页

作者： M.Eifel v.Caspary h.hnen p.Jeschke Institute of Jet propulsion and Turbomachinery RWTH Aachen University MAN Turbo AG

The present investigation analyzes the effects of major geometrical modifications to the interior of a convectioncooled gas turbine rotor blade. The main focus lies on the flow of the leading edge channels and the impact on theheat transfer. An experimental approach is performed with flow visualization via paint injection into water. Alsonumerical calculations are carried out in two sets, on the one hand water calculations accompanying the experimentsand on the other hand conjugate heat transfer calculations under realistic engine conditions. The latter calculationsare still ongoing delivering preliminary *** geometry configurations are investigated, three of them with differing turbulator arrangements in the leadingedge channels. The operating point of the base configuration is set to Re = 50,000 at the inlet while for the modifiedgeometries the pressure ratio is held constant compared to the *** several investigated configurations one could be identified that leads to a heat transfer enhancement inone leading edge channel 7 % larger compared to the base.

关键词： Convection cooling geometry modification experiment paint injection CFD conjugate heat transfer