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  • Author or Editor: I. Gómez x
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Abstract  

The publications by the Spanish scientists recorded in eight international databases in the years 1978 and 1983 are retrieved. Science indicators able to give a perception of the scientific productivity, the institutions involved, the habits of publishing in foreign or domestic journals and co-authorship are presented. The changes observed in these indicators in the two analysed years are examined and the trend in the evolution of the Spanish science is shown. The time delay in recording items by the databases and coverage of the Spanish journals are also studied.

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Abstract  

A procedure is described for neutron activation analysis of chlorine in zirconium and zirconium alloys. Calculation of chlorine concentration is performed relative to zirconium concentration in the matrix in order to minimize effects of differences in irradiation and counting geometry. Principles of the method, and the results obtained are discussed.

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Abstract  

3D quantitative elemental maps of a section of a strand of hair were produced using a combination of PIXE-Tomography and simultaneous On/Off Axis STIM-Tomography at the University of Surrey Ion Beam Centre. The distributions of S, K, Cl, Ca, Fe and Zn were determined using the PIXE-T reconstruction package DISRA. The results were compared with conventional bulk PIXE analysis of tomographic data as determined using Dan32. The overall concentrations determined by PIXE were compared with elemental concentrations held in the University of Surrey Hair Database. All the entries currently in the database were produced using INAA. The merits and possible contributions of tomographic PIXE analysis to analysis of hair are discussed. The conclusions drawn from the PIXE-Tomography analysis can be used to argue for more stringent procedures for hair analysis at the University of Surrey.

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Abstract  

This study is an analysis of six years of Spanish bibliography retrieved from INSPEC and COMPENDEX. The quantitative evolution of the scientific activity by years and Institutions, the recent tendencies to publish in foreign journals, as well as to have the papers signed by more authors are followed. The most frequently used journals are ranked according to their impact factor and subject. Some hypothesis are formulated and tested, trying to find a relationship between the growth of the Spanish scientific activity and its quality.

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Abstract  

A method for arsenic, antimony, selenium and molybdenum determination in water, loess and volcanic glasses, by radiochemical neutron activation analysis based on coprecipitation with Bi2S3 in hydrochloric medium, is described. The results of application to a study of natural contamination in the south-eastern region of the province of Córdoba, Republic of Argentina, are presented and discussed.

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Abstract  

Research projects in cooperation between Spanish National Research Council and Latin-American Organizations, that have been developed in the last eight years, were studied. Around forty Spanish research institutes have cooperated with Latin-American ones, mostly with Cuba, Chile, Brazil and Mexico. The interpretation of the collaboration rates with the different countries is discussed. Duration of the projects, number of researchers and research output were examined. The cooperation results were quantified through articles, presentations to congresses, reports, monographs, patents and thesis. Diffusion, languages and impact of the journals used for publication were studied. Non quantifiable outputs were also examined.

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The combined application of nitrogen (N) and zinc (Zn) appears to be a promising agronomic strategy for the biofortification with Zn. To evaluate such efficiency, a field experiment was conducted in south-eastern Portugal under Zn-deficient soil. Four advanced breeding lines and two commercial varieties of bread wheat (Triticum aestivum L.) were fertilized with five treatments: i) control, ii) two foliar Zn applications, iii) one foliar Zn+N application, iv) soil and two foliar Zn applications, and v) soil and one foliar Zn+N application. Grain Zn content varied greatly across treatments and INIAV-1 and the commercial varieties were the most interesting cultivars in all the treatments. Grain Zn concentrations higher than the target level of 38 mg Zn kg−1 were obtained only when two foliar Zn applications were applied, alone or in combination with soil Zn applications, and grain Zn bioavailability also was more adequate (phytate:Zn ratios similar to 15). Soil Zn application resulted in grain yield increases between 7–10%, which virtually offset the extra application cost. The combined soil and two foliar treatment could be a good option for biofortifying bread wheat under Zn-deficient soils.

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Journal of Thermal Analysis and Calorimetry
Authors: Lisardo Núñez-Regueira, M. Villanueva, I. Fraga, C. A. Gracia-Fernández and S. Gómez-Barreiro

Abstract  

The thermal degradation of an epoxy system consisting of a diglycidyl ether of bisphenol A (DGEBA, n=0) and m-xylylenediamine (m-XDA) was studied by both thermogravimetric analysis (TG) and dielectric analysis (DEA). It has been checked a deviation of the typical behaviour in the Arrhenius plot expected for this kind of systems, owing to the thermal degradation. Both, structural relaxation time and conductivity values, were represented as a function of the mass loss, that allow a relationship to be obtained between characteristic relaxation time and the degree of degradation at the beginning of the degradation process.

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