Showing papers by "National University of La Plata published in 1970"
30 citations
29 citations
TL;DR: In this paper, the conversion time relationship for a porous solid is calculated for an irreversible, first-order reaction with respect to the gaseous reactant and taking into account the diffusional resistances of the gas film and the ash layer.
29 citations
TL;DR: Experimental evidence in favour of an almost pure s helicity non-flip character at the nucleon-nucleon vertex of the Pomeron, f O and ω exchanges is discussed in this article.
26 citations
23 citations
TL;DR: In this paper, an X-ray diffraction study was made of copper electrodeposited on low index planes of copper single crystals, and three characteristic stages occurred during the process: epitaxial growth, twin development, and polycrystalline growth.
23 citations
TL;DR: In this paper, the electrochemical oxidation of nitrite ion in KNO 3 -Na NO 3 eutectic melt on a platinum rotating disk electrode has been studied in the temperature range 247 to 312°C.
18 citations
TL;DR: Toxicity episodes in mollusks from marine coastal waters of the Province of Buenos Aires (Argentina) associated to toxigenic algae (March 2008-March 2013) and eight outbreaks for lipophilic shellfish toxins (DSP/not determined) were recorded.
Abstract: Toxicity episodes in mollusks from marine coastal waters of the Province of Buenos Aires (Argentina) associated to toxigenic algae (March 2008-March 2013). Since a project of monitoring toxigenic microalgae and toxins in shellfish started in 2008, carried out along the coast betweenSan Clemente del Tuyu and Mar Azul (Northern Zone) and Bahia Anegada (Southern Zone) of the Province of Buenos Aires, four outbreaks of toxicity for paralytic shellfish toxins (PSP) and eight outbreaks for lipophilic shellfish toxins (DSP/not determined) were recorded. The results were used as technical tool from which the implementing authority (Direccion Provincial de Pesca of the Ministerio de Asuntos Agrarios of the Provincia de Buenos Aires) founded eleven decisions to impose closures and one sanitary alert to the consumption, extraction and commercialization of shellfish. Three of the PSP outbreaks occurred in the Northern Zone associated with Gymnodinium catenatum. The fourth episode occurred in Puerto Quequen associated with Alexandrium tamarense. In the same areathere were three DSP toxicity events, and associated species were Dinophysis acuminata and D. caudata. The remaining five episodes of toxicity for lipophilic toxins occurred in the Southern Zone, in one or more of the three sanitary areas classified as A by SENASA, and none of them could be associated with any of the known toxigenic species.
17 citations
TL;DR: In this article, an extension of Levich's solution for the convective-diffusion equation in a tube comprising an inert zone was applied, and the experimental numerical coefficient lies 10% lower than the one theoretically derived.
17 citations
TL;DR: In this article, the authors investigated the kinetics of the electrolytic evolution of hydrogen on iron electrodes using solutions of HCl in DMSO and derived the theoretical parameters from steady as well as from non-steady measurements.
16 citations
TL;DR: In this paper, the electrical conductance of hydrogen chloride solutions in DMSO at 25°C was studied and the authors interpreted the Fuoss' theory for associated 1-1 type electrolytes.
TL;DR: In this paper, a study of the complexes formed by chromium(III) with the acetate and propionate ligands at ionic strength μ = 0·3 in perchlorate medium and at selected conditions to exclude polynuclear complexes formation was made.
01 Jan 1970
TL;DR: In particular, en America Latina, los estudios de comunicacion apuntan cada dia con mas insistencia al analisis de los procesos comunicacionales entendidos como the construccion de relaciones and the intercambio de sentidos entre los actores sociales that comparten un determinado contexto cultural.
Abstract: Vivimos en un mundo mediatizado, en el que existe una tendencia a pensar la comunicacion en clave tecnologica e instrumental, poniendo la mirada en los medios masivos. Sin embargo, en particular en America Latina, los estudios de comunicacion apuntan cada dia con mas insistencia al analisis de los procesos comunicacionales entendidos como la construccion de relaciones y el intercambio de sentidos entre los actores sociales que comparten un determinado contexto cultural. La comunicacion para la salud ha sido entendida durante mucho tiempo como una herramienta para controlar y manipular las conductas individuales y colectivas. La revision de esas experiencias y la puesta en practica de una propuesta de comunicacion que analiza los multiples sentidos de las relaciones sociales, permite avanzar hacia la construccion de una perspectiva compleja de la realidad social. En esta perspectiva, lo comunicacional es una mirada que se articula con otras disciplinas y con los saberes vulgares, y los actores sociales tradicionalmente marginados o concebidos solo como parte del objeto de estudio son artifices del cambio comunitario. Se propone que los individuos y grupos que forman una comunidad puedan tomar la palabra para plantear sus necesidades y problemas, y articularse para intervenir activamente en la busqueda de soluciones, generando un cambio en los roles asignados tradicionalmente a los diferentes actores en materia de salud, en particular en lo referido a las relaciones de poder. La participacion comunitaria es un derecho ciudadano y un imperativo democratico, pero es tambien una via para aumentar la eficacia de las iniciativas sobre salud.
TL;DR: The kinetics of the electrochemical oxidation of graphite to volatile compounds by electrolysing molten bisulphates in the temperature range from 180 to 320°C has been studied by conventional steady-state and non-steady state measurements.
TL;DR: In this paper, a model of diffusion with simultaneous reaction was applied to predict the experimental results, taking into account the existence of effective diffusivity and surface area profiles through the zinc sulfide pellet and quantitatively stated by a correction factor of the Thiele modulus.
TL;DR: In this article, a criterion was developed to check the validity of the moving boundary model, based on the expression of the overall effectiveness factor for a gas-solid reaction obtained by computing the effective diffusivity and surface area profiles inside the reactant solid.
TL;DR: In this article, the appearance of spontaneous spectral lines is explained by the observation of eleven unknown spontaneous spectral spectral lines, which are observed in the laser line observation process, and the spectral properties of corresponding laser lines.
Abstract: Observation of eleven unknown spontaneous spectral lines explains the appearance of corresponding laser lines.
TL;DR: In this article, pyruvic and lactic acid determinations were performed in media with or without glucose, in order to show the activity of enzymes of the carbohydrate metabolism in that structure.
TL;DR: Theoretical expressions which include higher-order terms in the multipole expansion of the weak Hamiltonian and terms induced by strong interaction together with the variation of the lepton wave functions over the nuclei are presented for different β-decay observables as mentioned in this paper.
Journal Article•
TL;DR: In this paper, the diversity of ferns and lycophytes from Calilegua National Park, Jujuy Province Argentina has been studied, where taxa are grouped in 18 families and 43 genera.
Abstract: Diversity of ferns and lycophytes from Calilegua National Park, Jujuy Province Argentina. The biogeographic province of the “Yungas” is considered by the UNESCO as a Biosphere Reserve. In this zone, Calilegua National Park is one of the “cores” of the Yungas, where ferns and lycophytes grow as epiphytic, terrestrial or saxicoulous in different environments. The aim of this study is to make known the ferns and lycophytes that inhabit in Calilegua National Park, in order to provide information on Yungas biodiversity. For this purpose, 5 field trips were performed during december-May 2007-2011. Voucher specimens were deposited in the following herbaria: JUA, LP and RCV. Other herbaria and specific bibliography were also consulted. According to this study 103 taxa (species and varieties) of ferns and lycophytes inhabit in Calilegua National Park, grouped in 18 families and 43 genera. Six species are first recorded for the Province of Jujuy. Nomenclatural updates and keys for taxa identification are also given
TL;DR: In this paper, the electrical conductance of solutions of hydrogen chloride in dimethylsulphoxide at temperature from 25 to 45°C has been studied and the results have been interpreted with the Fouss theory for associated 1-1 type electrolytes.
TL;DR: El aparato de Golgi de las células somatotropas de la pars distalis de the hipofisis del ratón presenta importantes diferencias ultraestructurales en distintos momentos de un período de 24 horas.
Abstract: El aparato de Golgi de las celulas somatotropas de la pars distalis de la hipofisis del raton, presenta importantes diferencias ultraestructurales en distintos momentos de un periodo de 24 horas. Es pequeno a mediodia y marcadamente hipertrofico a mediodia y 6 de la tarde.
TL;DR: In this paper, theoretical current/voltage curves for reversible and simple irreversible electrode processes are calculated for a vertical plate electrode under isothermal and non-isothermal free convection.
TL;DR: In perfused dog hearts, paced at constant rate, the coronary infusion of glucagon was accompanied by an increase in contractility, coronary blood flow and myocardial oxygen consumption and a similar increase in MVO 2 when TCBF was kept constant by lowering coronary perfusion pressure.
TL;DR: The effect of graded changes in PCo2 upon intracellular hydrogen ion activity [H+]i of skeletal muscle of nephrectomized dogs was studied.
TL;DR: In this article, the signs of the Coriolis coupling constants ζ 1, ζ 2, and ζ 3 of characteristic E -type vibrations of XY 3 Z(C 3v ) molecules are explained by means of an approximate L matrix.
TL;DR: In this paper, the absorption of carbcn dioxide into aqueous solution of sodium hydroxide was studied in a packed column under conditions such that the accompanying reaction was of the second order.
Abstract: Absorption of carbcn dioxide into aqueous solution of sodium hydroxide was studied in a packed column under conditions such that the accompanying reaction was of the second order. In this case the average or volumetric reaction factor for the packed column, i.e. the ratio of the volumetric coefficients for absorption with and without chemical reaction, is complicated by the non-uniform contact-time distribution. However, the assumption of Porter''s "long, slow flow paths" model for the contact-time distribution led to a successful correlation for the average reaction factor.