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Search Results: 1 - 10 of 144184 matches for " ángel-Darío González-Delgado "
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MICROALGAE BASED BIOREFINERY: ISSUES TO CONSIDER
ángel-Darío González-Delgado,Viatcheslav Kafarov
CT&F - Ciencia, Tecnología y Futuro , 2011,
Abstract: Biorefining is sustainable biomass processing to obtain energy, biofuels and high value products through processes and equipment for biomass transformation. The biorefinery concept has been identified as the most promising way to create a biomass-based industry. Microalgae are classified as promising candidates in biorefinery processes because they are particularly important for obtaining multiple products. This review article describes the biorefinery concept taking into account its different interpretations and comparing it with the traditional biomass transformation processes. It describes the general characteristics of microalgae, and their potential to be used as a raw material in the biorefinery process. The review focuses on the state of the art of products obtained from microalgae for the biofuel industry, mainly for biodiesel production, and the different methods to extract oil for biodiesel production as well as other products. Based on this information, several aspects are suggested to be taken into account for the development of a topology for a microalgae-based biorefinery. Biorefinar es procesar biomasa de forma sostenible para obtener biocombustibles, productos comercializables y energía mediante procesos y equipos para la transformación de biomasa. El concepto de biorefinería ha sido identificado como el camino más prometedor para la creación de una industria basada en la biomasa. Las microalgas se catalogan como candidatas promisorias en procesos de biorefinería, siendo particularmente importantes por la obtención de múltiples productos. Este artículo de revisión, describe el concepto de biorefinería teniendo en cuenta sus diferentes interpretaciones y se compara con los procesos tradicionales de transformación de biomasa, se describen las características generales de las microalgas, y su potencial para ser utilizadas como materia prima en procesos de biorefinería, la revisión se enfoca en el estado del arte de los productos obtenidos de microalgas de interés para la industria de los biocombustibles y los diferentes métodos de extracción tanto de aceite para la producción de biodiesel como de otros productos y con base en esta información, se sugieren algunos aspectos a tener en cuenta para el desarrollo de una topología de biorefinería basada en microalgas. Biorefinar é processar biomassa de forma sustentável para obter biocombustíveis, produtos comercializáveis e energia mediante processos e equipamentos para a transforma o de biomassa. O conceito de biorefinaria tem sido identificado como o caminho mais prometedor para a cria o de u
Braquiópodos neógenos del suroeste de la depresión del Guadalquivir (sur de Espa?a)
Toscano-Grande, Antonio;García-Ramos, Diego;Ruiz-Mu?oz, Francisco;González-Regalado, María Luz;Abad, Manuel;Civis-Llovera, Jorge;González-Delgado, José ángel;Rico-García, Alberto;Martínez-Chacón, María Luisa;Xiomara García, Edith;Pendón-Martín, José Gabriel;
Revista mexicana de ciencias geológicas , 2010,
Abstract: this paper analyzes the first brachiopod record of three neogene formations of the southwestern guadalquivir basin (huelva province, sw spain) with a wide cartographical distribution. samples obtained in five sections of these formations have allowed to recognize three species belonging to the genera terebratula, maltaia and cryptopora, the latter being the first record of this genus in spain. in addition, the biostratigraphical distribution and palaeoecological context of these species and others present in upper neogene sediments (tortonian-lower pliocene) of south spain are discussed.
Análisis, diagnóstico y tratamiento de las intoxicaciones arsenicales
Suárez Solá,M.L.; González-Delgado,F.J.; González Weller,D.; Rubio Armendáriz,C.; Hardisson de la Torre,A.;
Cuadernos de Medicina Forense , 2004, DOI: 10.4321/S1135-76062004000100001
Abstract: arsenic (as) was isolated for the first time as a chemical element by jabir-ibn-haiyanb in the year 776, and its name comes etymologically from the greek arsenicon (masculine). it is gray in color and of a shining metallic appearance, has little metallic properties, is distributed widely in the universe and its toxicity depends on the different chemical forms and states of oxidation that it has: -3, 0, +3 and +5. the historical evolution of the toxicology is intimately united to the use of this nonmetal. at present, arsenical substances are used in industry, agriculture, cattle ranching, and medicine. for that reason, the sources of exposure of man to this metal are diverse; out standing are labor, food and medicaments. in this work a revision is made of the etiology, preventive measures, analysis, diagnosis and treatment of the poisoning by as.
Análisis, diagnóstico y tratamiento de las intoxicaciones arsenicales Analysis, diagnosis and treatment of arsenic poisoning
M.L. Suárez Solá,F.J. González-Delgado,D. González Weller,C. Rubio Armendáriz
Cuadernos de Medicina Forense , 2004,
Abstract: El arsénico (As) fue aislado por primera vez como elemento químico por Jabir-Ibn-Haiyanb en el a o 776 y su nombre procede etimológicamente del griego arsenicon (masculino). Es de color gris y apariencia metálica y brillante, posee escasas propiedades metálicas, se encuentra ampliamente distribuido en el universo y su toxicidad depende de las distintas formas químicas y estados de oxidación que posee: -3, 0, +3 y +5. La evolución histórica de la Toxicología está íntimamente unida al uso de este metaloide. Actualmente, las sustancias arsenicales se utilizan en la industria, en la agricultura y ganadería y en medicina. Por ello, las fuentes de exposición del hombre a este metal son diversas destacando la laboral, la alimentaria y la medicamentosa. En este trabajo se hace una revisión de la etiología, medidas preventivas, análisis, diagnóstico y tratamiento de las intoxicaciones por As. Arsenic (As) was isolated for the first time as a chemical element by Jabir-Ibn-Haiyanb in the year 776, and its name comes etymologically from the Greek arsenicon (masculine). It is gray in color and of a shining metallic appearance, has little metallic properties, is distributed widely in the universe and its toxicity depends on the different chemical forms and states of oxidation that it has: -3, 0, +3 and +5. The historical evolution of the toxicology is intimately united to the use of this nonmetal. At present, arsenical substances are used in industry, agriculture, cattle ranching, and medicine. For that reason, the sources of exposure of man to this metal are diverse; out standing are labor, food and medicaments. In this work a revision is made of the etiology, preventive measures, analysis, diagnosis and treatment of the poisoning by As.
Stellar populations of galaxies in the ALHAMBRA survey up to $z \sim 1$. I. MUFFIT: A Multi-Filter Fitting code for stellar population diagnostics
L. A. Díaz-García,A. J. Cenarro,C. López-Sanjuan,I. Ferreras,J. Varela,K. Viironen,D. Cristóbal-Hornillos,M. Moles,A. Marín-Franch,P. Arnalte-Mur,B. Ascaso,M. Cervi?o,R. M. González-Delgado,I. Márquez,J. Masegosa,A. Molino,M. Povi?,E. Alfaro,T. Aparicio-Villegas,N. Benítez,T. Broadhurst,J. Cabrera-Ca?o,F. J. Castander,A. Fernández-Soto,C. Husillos,L. Infante,J. A. L. Aguerri,V. J. Martínez,A. del Olmo,J. Perea,F. Prada,J. M. Quintana
Physics , 2015, DOI: 10.1051/0004-6361/201425582
Abstract: We present MUFFIT, a new generic code optimized to retrieve the main stellar population parameters of galaxies in photometric multi-filter surveys, and we check its reliability and feasibility with real galaxy data from the ALHAMBRA survey. Making use of an error-weighted $\chi^2$-test, we compare the multi-filter fluxes of galaxies with the synthetic photometry of mixtures of two single stellar populations at different redshifts and extinctions, to provide through a Monte Carlo method the most likely range of stellar population parameters (mainly ages and metallicities), extinctions, redshifts, and stellar masses. To improve the diagnostic reliability, MUFFIT identifies and removes from the analysis those bands that are significantly affected by emission lines. We highlight that the retrieved age-metallicity locus for a sample of $z \le 0.22$ early-type galaxies in ALHAMBRA at different stellar mass bins are in very good agreement with the ones from SDSS spectroscopic diagnostics. Moreover, a one-to-one comparison between the redshifts, ages, metallicities, and stellar masses derived spectroscopically for SDSS and by MUFFIT for ALHAMBRA reveals good qualitative agreements in all the parameters. In addition, and using as input the results from photometric-redshift codes, MUFFIT improves the photometric-redshift accuracy by $\sim 10$-$20\%$, and it also detects nebular emissions in galaxies, providing physical information about their strengths. Our results show the potential of multi-filter galaxy data to conduct reliable stellar population studies with the appropiate analysis techniques, as MUFFIT.
Pharmacokinetic and pharmacodynamic comparison of two "pegylated" interferon alpha-2 formulations in healthy male volunteers: a randomized, crossover, double-blind study
García-García Idrian,González-Delgado Carlos A,Valenzuela-Silva Carmen M,Díaz-Machado Alina
BMC Pharmacology , 2010, DOI: 10.1186/1471-2210-10-15
Abstract: Background Interferon (IFN) alpha conjugation to polyethylene glycol (PEG) results in a better pharmacokinetic profile and efficacy. The aim of this study was to compare the pharmacokinetic, pharmacodynamic and safety properties of a new, locally developed, 40-kDa PEG-IFN alpha-2b preparation with a reference, commercially available PEG-IFN alpha-2a in healthy male volunteers. Methods A randomized, crossover, double-blind study with a 3-weeks washout period, was done. A single 180 micrograms PEG-IFN alpha-2 dose was administered subcutaneously in both groups. Sixteen apparently healthy male subjects were included. Serum PEG-IFN concentration was measured during 336 hours by an enzyme immunoassay (EIA). Other clinical and laboratory variables were used as pharmacodynamic and safety criteria. Results The pharmacokinetic comparison by EIA yielded a high similitude between the formulations. In spite of a high subject variability, the parameters' mean were very close (in all cases p > 0.05): AUC: 53623 vs. 44311 pg.h/mL; Cmax: 333 vs. 271 pg/mL; Tmax: 54 vs. 55 h; half-life (t1/2): 72.4 vs. 64.8 h; terminal elimination rate (lambda): 0.011 vs. 0.014 h-1; mean residence time (MRT): 135 vs. 123 h for reference and study preparations, respectively. There were no significant differences with respect to the pharmacodynamic variables either: serum neopterin and beta-2 microglobulin levels, stimulation of 2'5' oligoadenylate synthetase expression, and serum IFN antiviral activity. A strong Spearman's rank order correlation (p < 0.01) between the pharmacokinetic and pharmacodynamic concentration-time curves was observed. Both products caused similar leukocyte counts diminution and had similar safety profiles. The most frequent adverse reactions were leukopenia, fever, thrombocytopenia, transaminases increase and asthenia, mostly mild. Conclusions Both formulations are fully comparable from the pharmacokinetic, pharmacodynamic, and safety profiles. Efficacy trials can be carried out to confirm clinical similarity. Trial registration Registro Público Cubano de Ensayos Clínicos RPCEC00000039.
Caracterización técnica y socioeconómica de la producción ovina en el estado de Yucatán, México
Góngora-Pérez,Rubén Darío; Góngora-González,Sergio Fernando; Maga?a-Maga?a,Miguel ángel; Lara y Lara,Pedro Enrique;
Agronomía Mesoamericana , 2010,
Abstract: technical and socioeconomic characterization of the ovine production in the state of yucatan, méxico. the objective was to determine the socioeconomic status of sheep production in the state of yucatán mexico, during year 2007. the investigation protocol consisted on the application of surveys through interviews forms, stratifying the production units (pu) by the number of wombs (e1 from 1- 20, e2 from 21-50, e3 more than 50). the feed sources were grassland, concentrated feed, rangeland and cut forage supplemented with minerals. continuous coupling (76.7%) was common, and artificial insemination is used only in e3 (2.2%). frequent diseases and with higher incidence in e1 were pneumonia (37%), clostridium (27.7%), and blackleg (20.2%) use of anti-parasites is out of time, each 6 months (41.7%) and each year (33.8%). care tacking of the pregnant sheep and lambs is conducted in a 63.3% and increases according to the number of wombs. mortality showed standard levels only in e, and the level of mortality was high during the nurturing period (12.2%). the main criteria to sell the animals were: animal weight and cash needs, and sales usually took place at the pu (83.7%). the highest costs are labor (workforce) (23.7%) and feeding (21.9%). income comes from the sale of animals with market weight and in post-weaning stage; profitability was positive only for e3, with standard earnings of $ 2.8 per kilo of standing meat.
Evaluación de la velocidad de corrosión- erosión en un acero API 5L grado 65 en un sistema salmuera-CO2-SiO2-aceite mineral, por medio de técnicas electroquímicas
Mu?oz-Fernández,Héctor Luis; González-Mendoza,Luis ángel; Pe?a-Ballesteros,Darío Yesid;
Ingeniería y Universidad , 2009,
Abstract: in the production and transportation of oil and gas there are many common problems of erosion-corrosion. the velocity of the flow and the drag of solid particles within the oil transported by pipelines are critical factors in the process of deterioration of low-carbon steels in the presence of co2. in this research, tests of erosion-corrosion were performed in a cell with a dynamic system of rotating cylinder electrodes at speeds between 1 and 3 m / s, particle sizes between 300/μm and 50//μm at concentrations between 1 and 9% by weight. techniques of direct current and alternating current were used to determine the corrosion rate under the conditions evaluated and determine the influence of the particles of sand and the speed of rotation on the corrosion rate of steel. a mathematical relation between the corrosion and system variables was calculated.
CARACTERIZACIóN TéCNICA Y SOCIOECONóMICA DE LA PRODUCCIóN OVINA EN EL ESTADO DE YUCATáN, MéXICO
Rubén Darío Góngora-Pérez,Sergio Fernando Góngora-González,Miguel ángel Maga?a-Maga?a,Pedro Enrique Lara y Lara
Agronomía Mesoamericana , 2010,
Abstract: El objetivo de este trabajo fue determinar la situación socioeconómica de la producción ovina en el estado de Yucatán México, durante el a o 2007. El método de investigación consistió en el levantamiento de encuestas mediante cédulas de entrevista, estratificando las unidades de producción (UP) por número de vientres (E1 de 1-20, E2 de 21-50 y E3 de más de 50). Las fuentes alimenticias son praderas, alimento concentrado, agostaderos y pasturas de corte, y se suplementa con minerales. El empadre continuo (76,7%) es común, la inseminación artificial se realiza solo en E3 (2,2%). Las enfermedades frecuentes y con mayor incidencia en E1 son: la neumonía (37%), clostridio (27,7%) y el carbón sintomático (20,2%). Los períodos de desparasitación se dan fuera de lo recomendado: cada seis meses (41,7%) y anual (33,8%). El cuidado de la hembra próxima al parto y del cordero, se realizan en un 63,3%, y aumenta según el estrato; mientras que los abortos disminuyen al aumentar el estrato. La mortalidad presentó índices normales, solamente en E1, la mortalidad predestete fue elevada (12,2%). Los principales criterios para la venta de animales fueron: peso del animal y necesidad de dinero, y ésta se realizó comúnmente en la UP (83,7%). Los gastos de mayor magnitud son: mano de obra (23,7%) y alimentación (21,9%). El ingreso proviene de la venta de animales con peso al mercado y destetes; la rentabilidad sólo fue positiva para el estrato 3, con ganancias promedio de $ 2,8 por kilogramo de carne en pie.
Evaluación de la velocidad de corrosión-erosión en un acero API 5L grado 65 en un sistema salmuera-CO2-SiO2-aceite mineral, por medio de técnicas electroquímicas
Héctor Luis Mu?oz-Fernández,Luis ángel González-Mendoza,Darío Yesid Pe?a-Ballesteros
Ingeniería y Universidad , 2009,
Abstract: In the production and transportationof oil and gas there are many commonproblems of erosion-corrosion.The velocity of the flow and thedrag of solid particles within the oiltransported by pipelines are criticalfactors in the process of deteriorationof low-carbon steels in the presence ofCO2. In this research, tests of erosioncorrosionwere performed in a cell witha dynamic system of rotating cylinderelectrodes at speeds between 1 and 3m / s, particle sizes between 300μmand 50μm at concentrations between1 and 9% by weight. Techniques ofdirect current and alternating currentwere used to determine the corrosionrate under the conditions evaluatedand determine the influence of theparticles of sand and the speed ofrotation on the corrosion rate of steel.A mathematical relation between thecorrosion and system variables wascalculated.
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