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Abstract  

A stack of natural samarium was bombarded with 87 MeV -particles. Cumulative cross sections for the production of145Eu,146Eu,147Eu,148Eu,150Eu,152Eu and154Eu have been studied using gamma-ray spectroscopy. The data are compared with the theoretical results provided by equilibrium and pre-equilibrium reaction models, for this purpose we used the code ALICE of Blann.

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Abstract  

Excitation functions and isomeric ratios for184Re, from -induced reactions on181Ta and natural W have been measured using the stacked-foil method. The data are compared with the theoretical predictions provided by the equilibrium and pre-equilibrium reaction model; for this propose we used the code INDEX development by ERNST.

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At the present time, the quality, integrity, sanitation, and nutritional value of honeys receive attention on an international level due to the increasing content of chemicals in the aforementioned matrix. The present study aims to characterize organic honey (n=73) from Northeast Portugal, with respect to floral nectar origin, physicochemical parameters, microbial safety, and commercial quality. All organic honey samples can be classified as monofloral lavender (Lavandula stoechas L.), exceed in quality the international physicochemical standards, and show low microbiological counts (yeast, moulds, and aerobic mesophiles), with negative results in respect to faecal coliforms, Salmonella, and sulphite-reducing clostridia. Correlating the palynological, physicochemical, and microbiological results is necessary in order to check the authenticity, quality, and sanitation of honey.

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Abstract  

Excitation functions and isomeric ratios for102Rh, from the -induced reactions on103Rh, have been measured between 15 and 89 MeV. The results show characteristic features of the pre-equilibrium process. The excitation functions were determined by the stacked foil method.

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The effects of environment and the high molecular weight glutenins on some quality properties (sedimentation volume, % protein content, and starch pasting viscosity) of bread wheat mutant waxy lines were evaluated. Thirty-eight 100% amylose-free F 2 derived F 6 and F 7 lines were used. The results indicated that the environment did not influence sedimentation volume, mixograph parameters and starch viscosity parameters of waxy flour. Variation in the % protein content was determined mainly by the environment. The sedimentation volume and the mixograph peak development time were influenced by the variation at over expression of Bx7 and the mixograph peak development time was influenced by the Glu-D1 locus. One starch viscosity parameter, time to peak viscosity, was influenced by variation at the Glu-A1 locus. This parameter is significantly lower in the waxy lines than the parent line, which shows the influence of the waxy loci. No significant correlation was observed for sedimentation volume, mixograph parameters, protein content and viscosity parameters of waxy lines.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: M. Vázquez, M. Ozafrán, M. de la Vega Vedoya, and S. Nassiff

Abstract  

Target foil stacks of niobium were bombarded with beams of alpha particles at incident energies ranging from 0 to 90 MeV. Cumulative cross sections for the production of95(m+g)Nb,92mNb,91mNb and90(m+g)Nb were determined by semiconductor gamma-spectrometry of the residual activity of stacked foils. On the basis of the cumulative cross sections, the thick target yields and saturation production rates of niobium isotopes have been evaluated.

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Journal of Thermal Analysis and Calorimetry
Authors: R. Briones-Martínez, M. Juárez-Juárez, M. Oliver-Salvador, and M. Cortés-Vázquez

Abstract  

DSC was used to study the extent of denaturation of hemisphaericin and mexicain hydrolysates from corn gluten, soybean and sunflower meals. It was observed that the defatted meals studied exhibited only one broad peak transition. The data obtained demonstrated that the partial protein denaturation found with hemisphaericin or mexicain is correlated to modifications of functional properties. The two enzymes display different modes of action, according to the protein source.

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Abstract  

A stack of natural copper was bombarded with -particles. Cumulative cross-sections for65Ga,66Ga and65Zn production, and the excitation functions for68Ga and67Ga production, were measured using high resolution gamma-ray spectroscopy. The data are compared with the theoretical result provided by equilibrium and pre-equilibrium reaction model, for this purpose we used the code ALICE of Blann. The overall agreement with theory is good. Besides, we present the experimental data obtained by other authors.

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Journal of Thermal Analysis and Calorimetry
Authors: M. López, M. Blanco, A. Vazquez, J. Ramos, A. Arbelaiz, N. Gabilondo, J. Echeverría, and I. Mondragon

Abstract  

The curing kinetics of nanocomposites based on phenolic resol cured with triethylamine (TEA) containing different amounts of organic montmorillonite was analyzed by differential scanning calorimetry. Kissinger-Akahira-Sunose (KAS) model-free kinetics has been applied to correlate the dynamic cure behaviour in the presence of modified montmorillonite. The effect in the curing of the use of different clay modifiers has also been studied. A commercial clay with hydroxyl groups (Cloisite 30B) and a customized montmorillonite (PheMMT) whose reactive groups induce condensation reactions with the resol matrix have been used. Strong dependency of activation energy on apparent conversion has been observed for all compounds.

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