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  • Author or Editor: J. Rodríguez x
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Abstract  

The molality dependence of specific conductivity of pentadecyl bromide, cetylpyridinium bromide and cetylpiridinium chloride in aqueous solutions has been studied in the temperature range of 30–45 °C. The critical micelle concentration (cmc) and ionization degree of the micelles, β, were determined directly from the experimental data. Thermal parameters, such as standard Gibbs free energy
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\Updelta G_{m}^{0} ,$$ \end{document}
enthalpy
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\Updelta H_{m}^{0}$$ \end{document}
and entropy
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\Updelta S_{m}^{0} ,$$ \end{document}
of micellization were estimated by assuming that the system conforms to the pseudo-phase separation model. The change in heat capacity on micellization
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\Updelta C_{p} ,$$ \end{document}
was estimated from the temperature dependence of
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An enthalpy–entropy compensation phenomenon for the studied system has been found.
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The growth and development of research in the field of ecology

As measured by dissertation title analysis

Scientometrics
Authors: Ketty Rodríguez and J. Moreiro

Abstract  

This study assesses the growth, the patterns of development and the complexity of research in the field of ecology from 1976 to 1993 in Spain and the five Spanish speaking countries of the Caribbean. Using as a yardstick of research and development in that field, the dissertation titles were counted for each region. The total length, the key words per title were recorded and analysed statistically. Results show that the growth of research in ecology is greater in Spain and peaked earlier than in the Caribbean countries. However, the titles in the latter region were more complex than those in Spain.

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Abstract

In this study, I examine a hitherto completely unknown subject: the Hungarian reception of Manuel de Falla's ballet pantomime, El sombrero de tres picos (The three-cornered hat). As I point out, the story of the piece began well before Falla composed his music: Alarcón's novel was published in a Hungarian translation just two decades after the Spanish original. In the first decades of the twentieth century, the Budapest Opera House (Magyar Állami Operaház) and Municipal Theatre (Városi Színház) developed intensive opera, theatre, and ballet seasons, in association with the main European capitals during the first decades of the twentieth century. De Falla's ballet was premiered in Budapest in 1927 by Diaghilev's Russian Ballet, in the Municipal Theatre under the Hungarian title A háromszögletű kalap. The piece had such success that it had to be repeated three times. What is more, a Hungarian production was premiered in the Budapest Opera House one year later and this production continued until 1963, delivering a total of 75 performances. The sources (among others the handwritten performing scores) of this latter production preserved in the National Széchényi Library and in the Archives of the Hungarian State Opera House reveal an intense work of choreographic adaptation, along with careful design of staging, costumes, lightning, and scenery effects, all accomplished by great international personalities to make this very Spanish ballet understandable to the Magyar audience. Falla's work also found a significant support in the press, highlighting both the plot's universality and the expressiveness of his music, which had made it a Hungarian success.

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Abstract  

The aim of this work was to demonstrate, by means of thermoanalytical methods (DTA, TG and DTG), that sepiolite from Vallecas (Spain) is mixed with another mineral which is difficult to determine by X-ray diffraction and chemical analysis in routine mineralogical studies. The low temperature endothermic effect and weight loss shown by this material can be separated into two effects: one from sepiolite and the other from an accompanying mineral-identified as a magnesium smectile. The concentration of this latter mineral in the mixture attained up to 15%.

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Summary  

We present new properties of the Besov--Hankel spaces introduced in [10]. We prove a Hankel version of a result of Bui, Paluszyński and Taibleson obtaining new norms that define the topology of the Besov--Hankel spaces. Also we get atomic representations for the distributions in the spaces under consideration.

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A GC-FID method for major volatile analysis in cider and wine was validated under the requirements of the ISO/IEC 17025 regulation using a split mode injection. This method presented a good linearity (R2>0.999, Cm>99%), a wide range of calibration, the maximum random errors for repeatability and intermediate precision were 5% and 8%, respectively, and the maximum limit of quantification and limit of detection were 14.1 mg l–1 and 4.6 mg l–1, respectively. Trueness, expressed as recovery (%), was successfully validated by means of two different methods, standard addition (92–110%) and comparison against reference materials (93–115%). Expanded uncertainty estimated at 95% confidence level ranged between 11% for methanol and 7% for allyl alcohol. The validated method was successfully applied for the analysis of major volatiles in ciders and wines, and to detect yeast and lactic acid bacteria spoilage.

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