Search results for "RME"
showing 10 items of 6748 documents
First stages of microsporere programming to embryogenesis through anther culture in Prunus armeniaca L.
2011
6 páginas, 3 figuras, 2 tablas -- PAGS nros. 152-157
Induction of pollen embryogenesis in seven cultivars of Prunus armeniaca l.
2010
6 páginas -- PAGS nros. 273-278
Nyctiphanes couchii as intermediate host for Rhadinorhynchus sp. (Acanthocephala, Echinorhynchidae) from NW Iberian Peninsula waters
2013
12 páginas, 3 figuras, 3 tablas
Photocatalytic oxidation of phenol on TiO2 powders. A Fourier transform infrared study
1994
Abstract In the present paper a detailed investigation of a well known photoreaction, i.e. phenol photodegradation in the presence of TiO2, has been carried out. The Fourier transform infrared (FT-IR) technique has been used to characterize the catalyst surface and to follow the photoprocess by “in situ” measurements in a gas—solid regime, simulating the aqueous liquid—solid regime in which this photodegradation reaction has been usually carried out. The influence on the photoprocess of the surface hydroxylation of the catalyst has been investigated and the presence of some reaction intermediates has been revealed by FT-IR. The experimental results have demonstrated that the chosen gas—soli…
Mark-Houwink Parameters of Biosynthetic Poly(γ-glutamic acid) in Aqueous Solution
2001
A combined viscosity–light scattering–gel permeation chromatography (GPC) study was carried out on bacterially produced poly(γ-glutamic acid) (PGGA). PGGA samples with weight-average molecular weights ranging from 8×104 up to 8×105 g·mol–1 dissolved in phosphate buffer at 0.13 M ionic strength were used. It was found that the Mark–Houwink relation is acceptably obeyed, giving K and a values of 1.84×10–6 dL·g–1 and 1.16, respectively. As expected, GPC analysis showed that PGGA does not follow the universal calibration plot and that deviations can not be avoided by modifying the ionic strength.
Measurement of interactions between polysaccharides and flavour compounds by exclusion size chromatography: Advantages and limits
1998
Interactions between flavour compounds and polysaccharides have been studied by exclusion size chromatography, the Hummel and Dreyer method. Hydrogen bonding was found between 2-acetyl thiazole and dextrines of different degrees of polymerisation. The number of binding sites and the affinity constant increase by increasing the degree of polymerisation. Hydrogen bonding was also responsible for the interactions between xanthane and 1-octen-3-ol or 2-acetyl pyrazine, with 1 mole of 1-octen-3-ol bound per pentasaccharide repeating unit. Unfortunately, the number of flavour compounds, which can be studied with this method, is limited due to their low water solubility and their low UV absorption.
Membranes Directly Prepared from Solutions of Unsubstituted Cellulose
2005
Summary: Starting from 5 wt.-% solutions of a prehydrolysis kraft pulp ( = 135 kg · mol−1) in the mixed solvent (dimethylacetamide + 7 wt.-% LiCl) we have prepared cellulose membranes on different supports according to the phase inversion process using above all acetone (AC) and 2-propanol as precipitants. In this context we have studied the phase behavior of the quasiternary system (DMAc+LiCl)/AC/cellulose. The obtained membranes are mechanically stable and in their mechanical and separation properties on the whole comparable to membranes consisting of regenerated cellulose. With respect to gas separation the ideal selectivity of CO2 in combination with N2 and O2 turns out to be opposite f…
NEW GRAFT COPOLYMERS OF HYALURONIC ACID AND POLYLACTIC ACID: SYNTHESIS AND CHARACTERIZATION
2006
Abstract New graft copolymers have been synthesized, using hyaluronic acid (HA) as a hydrophilic backbone and polylactic acid (PLA) as an aliphatic polyester in order to obtain new polymeric derivatives of HA able to hydrophobically associate in an aqueous medium. Hyaluronic acid with low molecular weight was made soluble in organic solvent by transformation to its tetrabutylammonium (TBA) salt. Using the HA–TBA derivative, the reaction was performed in dimethylsulfoxide adding as a reagent the N -hydroxysuccinimide derivative of PLA. Two HA–PLA graft copolymers have been synthesized and characterized by FT-IR, 1 H NMR spectroscopy and gel permeation chromatography. The interaction between …
L'article 48 du code de procédure civile est inapplicable aux clauses d'arbitrage et la clause d'arbitrage, stipulée dans un contrat d'assurance, n'e…
2019
International audience; (Cass. 5 sept. 2018, n° S 17-13.837, F-D, Soc. RSUI Indemnity Company c/ Soc. Tenergie Developpement et autres, inédit)
Could malaria and dengue reappear in Spain?
2010
El aumento de la inmigración durante los últimos años en España ha facilitado la importación de numerosas enfermedades tropicales. Entre ellas, las de transmisión vectorial son algunas de las más complicadas de estudiar por la complejidad que conlleva la participación de diversos hospedadores en los ciclos de transmisión, así como por la necesidad de conocer todos los parámetros fisiológicos, bioecológicos y biogeográficos relacionados con el organismo vector para poder inferir las posibilidades reales de la emergencia o la reemergencia de las enfermedades pertinentes. En estas circunstancias, el presente trabajo aporta información acerca de enfermedades importadas de incuestionable interés…