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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

Seminal characteristics and sexual behavior in men of different age groups： is there an aging effect？

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Asian Journal of Andrology 2006年第A3期8卷 337-341页

作者： Panayiotis M. Zavos Khalied Kaskar Juan R. correa Suresh C. Sikka Andrology Institute of America Lexington Kentucky 40523 USA Centre de Fertilidad del Caribe Rio Piedras Puerto Rico 00923 USA Department of Urology Tulane University School of Medicine New Orleans Louisiana 70118 USA

Aim： To assess the seminal characteristics as well as the sexual behavior of men of various age groups to establish the presence of an aging effect on those characteristics. Methods： Semen samples were collected from men （n = 792） undergoing in vitro fertilization or intrauterine insemination in cases of female factor infertility only. Samples were collected using a seminal collection device at intercourse and evaluated manually according to World Health Organization （WHO） standards. Men were divided into four groups according to their ages：（i） 20-30, （ii） 31-40, （iii） 41-50 and （iv） 51-60 years, and their seminal characteristics and responses to a sexual behavior questionnaire were compared. Results： The data showed statistically significant differences in the seminal characteristics tested, most notably in the sperm concentration, motility, grade of motility, hypo-osmotic swelling and normal sperm morphology. Furthermore, the decline in normal sperm morphology with age was more pronounced when using strict criteria rather than WHO standards. There were also differences in total sperm count, total motile sperm and total functional sperm fraction （assessed by both WHO and strict criteria）. Significant differences were also observed in the sexual behavior patterns in older men in terms of the number of years they have been trying to conceive, sexual frequency and sexual satisfaction. Conclusion： The data clearly illustrate an aging effect on semen characteristics and sexual behavior in men as they age. It is suggested that the aging effect be taken into consideration when proposing normal standard values for semen characteristics in routine semen analysis as outlined by WHO standards.

关键词： seminal parameters male aging effect fertility sexual behavior semen quality male factor infertility

Partitioning between primary and secondary metabolism of carbon allocated to roots in four maize genotypes under water deficit and its effects on productivity

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The Crop Journal 2015年第5期3卷 379-386页

作者： Alyne Oliveira Lavinsky Paulo Cesar Magalhaes Roniel Geraldo avila Mariana Melo Diniz Thiago correa de Souza Embrapa Milho e Sorgo Sete LagoasMGCEP:35701-970Brazil Universidade Federal de Lavras LavrasMGCEP 37200-000Brazil Universidade Federal de Sao Joao Del Rey Sete LagoasMGCEP 35701-970Brazil Universidade Federal de Alfenas AlfenasMGCEP 37130-000Brazil

Plants may respond to drought by altering biomass allocation to shoots and roots or by changing the metabolic activities in these organs. To determine how drought changes the partitioning of carbon allocated to growth and secondary metabolism in maize roots and how it affects photosynthesis(A) and productivity in maize, we evaluated leaf gas exchange, yield componentes, root morphology, and primary and secondary metabolites including total soluble sugars(TSS), starch(S), phenolics(PHE), and lignin(LIG). Data were collected from pot-grown plants of four maize genotypes: BRS 1010 and 2B710(sensitive genotypes) and DKB390 and BRS1055(tolerant genotypes) under two soil water tensions: field capacity(FC,-18 kP a) and water deficit(WD,-138 kP a). WD was applied at the pre-flowering stage for 12 days and then the water supply was restored and maintained at optimum levels until the end of the cycle. For genotype BRS 1055 under FC, the greatest A did not result in greater grain biomass(DGB) because the accumulated photoassimilates had already filled the cells, and thus the excessive TSS synthesized in leaves was allocated to roots in large amounts. However, the sharp decrease in A caused by WD imposition in this genotype did not affect the influx pressure of leaf TSS, which was due largely to conversion of primary metabolites to PHE compounds to increase the length of fine roots. In leaves of DKB390 under WD, both S and TSS were reduced, whereas PHE were increased to prevent excessive water loss and xylem cavitation. Under WD, both BRS1010 and2B710 genotypes displayed reduced allocation of biomass to shoots and roots and LIG content in leaves, as well as lower A and DGB values. In BRS1010 this response was coupled to S decrease in leaves and TSS increase in roots, whereas in 2B710 there was a concomitant S increase in roots.

关键词： Starch Sugars Lignin Phenols WinRHIZO

Complete polarization control in multimode fibers with polarization and mode coupling

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Light(Science & Applications) 2018年第1期7卷 603-612页

作者： Wen Xiong Chia Wei Hsu Yaron Bromberg Jose Enrique Antonio-Lopez rodrigo Amezcua correa Hui Cao Department of Applied Physics Yale UniversityNew HavenCT 06520USA Racah Institute of Physics Hebrew University of JerusalemJerusalem 91904Israel CREOL The College of Optics and PhotonicsUniversity of Central FloridaOrlandoFL 32816USA

Multimode optical fibers have seen increasing applications in communication,imaging,high-power lasers,and ***,inherent imperfections and environmental perturbations cause random polarization and mode mixing,causing the output polarization states to be different from the input polarization *** difference poses a serious issue for employing polarization-sensitive techniques to control light–matter interactions or nonlinear optical processes at the distal end of a fiber ***,we demonstrate complete control of polarization states for all output channels by only manipulating the spatial wavefront of a laser beam into the *** polarization states for individual output channels are generated by wavefront shaping without constraining the input *** strong coupling between the spatial and polarization degrees of freedom in a multimode fiber enables full polarization control with the spatial degrees of freedom alone;thus,wavefront shaping can transform a multimode fiber into a highly efficient reconfigurable matrix of waveplates for imaging and communication applications.

关键词： polarization fiber multimode

Distribution of the related weevil species Sitophilus oryzae and S. zeamais in Brazil

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Insect Science 2013年第6期20卷 763-770页

作者： Alberto S. correa Luiz Orlando de Oliveira Lucas S. Braga Raul Narciso C. Guedes Departamento de Entomologia Universidade Federal de Vicosa Vicosa Brazil Departamento de Bioquimica e Biologia Molecular Universidade Federal de Vicosa Vicosa Brazil

The genus Sitophilus （Coleoptera： Curculionidae） encompasses species of great economic importance as stored grain pests worldwide. Among these species, the maize and the rice weevils （Sitophilus zeamais and Sitophilus oryzae, respectively） are partic- ularly important in warmer climates. These two weevils exhibit closely morphological and ecological resemblance making difficult their proper identification and recognition of their distribution in grain-producing regions. Both species are recorded in South America and particularly in Brazil, but their respective distribution and prevalence were not yet assessed in the region. Therefore, several insect samples throughout Brazil were collected and subjected to morphological identification using male genitalia and also using molec- ular identification with species-specific primers designed for clear recognition of both the species. The primers were designed for the specific amplification of a gene fragment of the cytochrome oxidase subunit I, which exhibited high specificity during our prelimi- nary experiments with insects from six populations of known species （either S. zeamais or S. oryzae）. Both identification strategies provided the same results indicating preva- lence of the maize weevil S. zeamais throughout the country. Two hypotheses may explain such prevalence：（i） the likely host preference ofS. zeamais for maize because this is the most cultivated cereal in Brazil, and （ii） the prevalence ofS. zeamais in tropical regions as compared with S. oryzae, which is more disseminated in subtropical and temperate regions.

关键词： cytochrome oxidase subunit I distribution maize weevil rice weevil South America

Human immunodeficiency virus type-1 induces a regulatory B cell-like phenotype in vitro

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Cellular & Molecular Immunology 2018年第10期15卷 917-933页

作者： Jacobo Lopez-Abente Adrián Prieto-Sanchez Maria-Ángeles Muñoz-Fernandez Rafael correa-Rocha Marjorie Pion Laboratorio de Inmuno-Regulación Immunology DepartmentPabellón de Medicina y Cirugía ExperimentalHospital General Universitario Gregorio MarañónInstituto de Investigación Sanitaria Gregorio Marañón(IiSGM)Calle Máiquez9Madrid 28009Spain Laboratorio de Inmuno-Biología Molecular Immunology DepartmentHospital General Universitario Gregorio MarañónInstituto de Investigación Sanitaria Gregorio Marañón(IiSGM)C/Dr.Esquerdo 46Madrid 28007Spain Networking Research Center on Bioengineering Biomaterials and Nanomedicine(CIBER-BBN)C/Monforte de Lemos 3-5Pabellón 11Madrid 28029Spain

Individuals infected with human immunodeficiency virus type-1(HIV-1)usually show a general dysregulation and hyper-activation of the immune system.A direct influence of HIV-1 particles on B-cell phenotypes and functions has been previously ***,the consequences of B-cell dysregulation are still poorly *** evaluated the phenotypic changes in primary B cells after direct contact with HIV-1 particles in comparison with different types of *** functionality of treated B cells was challenged in co-culture experiments with autologous CD4+and CD8+T *** demonstrated that HIV-1 induces a phenotypic change in B cells towards a regulatory B-cell phenotype,showing a higher level of IL-10,TGF-β1,EBI3 or IL-12(p35)mRNA expression and acquiring an immunosuppressive *** acquisition of a Breg phenotype was confirmed by co-culture experiments where HIVtreated B cells reduced the proliferation and the TNFαproduction of CD4+or CD8+T *** suppressive ability of HIV-treated B cells was dependent on cell-to-cell contact between these B cells and effector *** our knowledge,these data provide the first evidence that HIV-1 can directly induce a regulatory B cell-like immunosuppressive phenotype,which could have the ability to impair specific immune *** dysregulation could constitute one of the mechanisms underlying unsuccessful efforts to develop an efficient vaccine against HIV-1.

关键词： HIV-1 immune hyper-activation regulatory B cells

Pt Supported on Plasma-Chemical Titanium Nitride for Efficient Room-Temperature CO Oxidation

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Modern Research in Catalysis 2022年第1期11卷 1-11页

作者： David correa Coyac Eugene Kabachkov Eugene Kurkin Nikolay Vershinin Igor Balikhin Viktor Berestenko Alexandre Michtchenko Yury Shulga Instituto Politécnico Nacional SEPI-ESIME-Zacatenco Av. IPN S/N Ed.5 3-r piso Ciudad de Mexico Mexico Federal Research Center of Problem of Chemical Physics and Medicinal Chemistry Russian Academy of Sciences Chernogolovka Russian Federation Institute of Solid State Physics Russian Academy of Sciences Chernogolovka Russian Federation

Catalysts of carbon monoxide oxidation were synthesized by deposition of platinum on titanium nitride (TiN). Two substrates with an average particle size of 18 and 36 nm were obtained by hydrogen reduction of titanium tetrachloride in a stream of microwave plasma of nitrogen. The surface of the catalysts was studied by X-ray photoelectron spectroscopy (XPS). The data obtained by us in the present work indicate the presence of oxynitride as a transition layer between nitride and oxide. It was found that the CO oxidation rate on the 9 - 15 wt.% Pt loaded TiN catalysts is 120 times higher than that on the platinum black with a specific surface of 30 m2/g. Increase in the reaction rate of CO oxidation on Pt/TiN catalysts as compared to platinum black can be associated with both an increase in the concentration of CO molecules adsorbed and a decrease in the activation energy of the reaction. Catalysts are promising for use in catalytic air purification systems.

关键词： CO Oxidation Titanium Nitride Pt/TiN Catalysts Carbon Monoxide Microwave Plasma Platinum Black X-Ray Photoelectron Spectroscopy

Gabor superlens with variable focus

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Chinese Optics Letters 2020年第12期18卷 68-72页

作者： A.Garza-Rivera J.E.Gomez-correa F.J.Renero-Carrillo J.P.Trevino V.Coello INAOE Departtunento de OpticaTonantzintlaPuebla72840Mexico Catedras Conacyt-CICESE Unidad MonterwyPUT ApodacaNuevo Leon66629Mexico Tecnoldgico de Monterrey Campus PueblaDepartainento de Bioingenicrfay CicnciasPueblaPuebla72453Mexico CICESE Unidad MonterreyPUT ApodacaNuevo Leon66629Alexico

In this Letter,a Gabor superlens with variable focus is presen *** configuration uses tunable liquid lenses in the third microlens array of the Gabor *** applying voltage,the radius of curvature of the microtunable doublet arrays changes,and the Gabor conditions are fulfilled at different focal *** a consequence,the magnification of the image at the focal planes changes,and a zoom effect is *** marginal depth plane for this system goes from 0.86 to 0.89 *** optical simulation,calculations,and results of the simulated optical system performance are presented.

关键词： Gabor superlens micro-tunable lens multi-aperture optics geometric optical design

Nanocellulose-based porous materials: Regulation and pathway to commercialization in regenerative medicine

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Bioactive Materials 2023年第11期29卷 151-176页

作者： Filipe V.Ferreira Alana G.Souza Rubina Ajdary Lucas P.de Souza Jo˜ao H.Lopes Daniel S.correa Gilberto Siqueira Hernane S.Barud Derval dos S.Rosa Luiz H.C.Mattoso Orlando J.Rojas Nanotechnology National Laboratory for Agriculture(LNNA) Embrapa Instrumentation-Rua XV de Novembro1452S˜ao CarlosSP13560-979Brazil Center for Engineering Modelingand Applied Social Sciences(CECS)Federal University of ABC(UFABC)Santo Andr´eBrazil Department of Bioproducts and Biosystems School of Chemical EngineeringAalto UniversityP.O.Box 16300AaltoEspooFIN-00076Finland College of Engineering and Physical Sciences Aston Institute of Materials ResearchAston UniversityBirminghamUK Department of Chemistry Division of Fundamental Sciences(IEF)Technological Institute of Aeronautics(ITA)S˜ao Jose dos CamposSPBrazil Laboratory for Cellulose&Wood Materials Empa-Swiss Federal Laboratories for Materials Science and TechnologyÜberlandstrasse 1298600DübendorfSwitzerland Biopolymers and Biomaterials Laboratory(BIOPOLMAT) University of Araraquara(UNIARA)Araraquar114801-340S˜ao PauloBrazil Bioproducts Institute Department of Chemical&Biological EngineeringDepartment of Chemistry andDepartment of Wood ScienceThe University of British Columbi12360 East MallVancouverBCV6T 1Z3Canada

We review the recent progress that have led to the development of porous materials based on cellulose nanostructures found in plants and other resources. In light of the properties that emerge from the chemistry, shape and structural control, we discuss some of the most promising uses of a plant-based material, nanocellulose, in regenerative medicine. Following a brief discussion about the fundamental aspects of self-assembly of nanocellulose precursors, we review the key strategies needed for material synthesis and to adjust the architecture of the materials (using three-dimensional printing, freeze-casted porous materials, and electrospinning) according to their uses in tissue engineering, artificial organs, controlled drug delivery and wound healing systems, among others. For this purpose, we map the structure-property-function relationships of nanocellulose-based porous materials and examine the course of actions that are required to translate innovation from the laboratory to industry. Such efforts require attention to regulatory aspects and market pull. Finally, the key challenges and opportunities in this nascent field are critically reviewed.

关键词： Cellulose nanofibrils Cellulose nanocrystals Regenerative medicine Biomaterial Sustainable materials Green nanomaterials