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Abstract  

Ammonium uranate was precipitated from uranyl nitrate solution using gaseous ammonia, then filtered, washed with demineralized water and dried. The influence of pH and ammonia flow rate on their composition and structure were examined by X-ray diffraction analysis, making use of additional information obtained from infrared analysis.

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Abstract  

Irradiation of α-Al2O3 (Corundum) was carried out in contact with acidic media and with different doses (100-to-2500 kGy) and dose-rates (0.9, 2.6 and 6.1 kGy·h−1) of γ-rays. Simultaneously parallel experiments were carried out using the same procedure, but preheated at 150°C for two days and then irradiated without acidic media. The solid thus obtained was used to determine the effect of γ-irradiation on the sorption capacities of microamounts of fission products from strongly alkaline aqueous solutions of uranium. The results revealed that the effect of γ-irradiation of α-Al2O3 and the acidic media in which it is immersed, is associated with a stable matrix resistant to significant changes in the composition of the surface layer; whilst it seems that the effect of γ-irradiation of preheated α-Al2O3, is connected with changes of surface-OH groups strongly affected by heat treatment and irradiation dose.

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Abstract  

The use of ionizing radiation to achieve some desired effect on silica gel, applicable to the adsorption of radionuclides has been investigated as a function of the dose-rate over a wide range of doses, in experiments with strongly alkaline aqueous solutions containing an excess of UO 2 2+ relative to trace concentrations of88Y,103Ru,134Cs and141Ce. The results obtained revealed that γ-irradiation of silica gel was reproduced with an uptake comparable to that measured for the unirradiated-silica gel. Radiation resistance is strongly influenced by the basic macromolecular structure, the presence of water, and the particular environmental exposure conditions.

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Abstract

This article provides an empirical assessment of the performance of the member states of the Association of Southeast Asian Nations in terms of science, technology, and innovation. This study is relevant because it employs a larger data set, examines more countries, and covers more years than previous studies. The results indicate that these countries had differing patterns of performance, and the pattern of growth among them was asymmetrical. Additional findings suggest that these countries performed idiosyncratically with respect to the six quantitative dimensions we examined. Our research includes a form of comparative policy evaluation that might assist the monitoring of the implementation of “Vision 2020”. The results simplify how we determine the relative strengths and weaknesses of national innovation systems and are relevant to policy discussions. In relation to transferability, the findings demonstrate similarities to the European Union with regard to performance and governance.

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Abstract  

José Antonio Alzate dam mud sediment samples were collected from six sampling sites. The samples were analyzed by combining multielemental studies with structural details, including heating to very high temperatures. Characterization of mud sediment samples have been shown to have low concentrations of metals (Cr, Mn, Ni, Cu, Zn, Pb). No systematic trend was observed as a function of the sampling points.

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Abstract  

Thermal analysis of jute fibre reinforced vinylester resin with 30 vol% of fibre were performed by TG/DTG under dynamic conditions. The fibres were treated with alkaline solution at different temperatures and the final composition (cellulose, hemicellulose and lignin) of the fibre was determined by chemical analysis. Apparent activation energies were determined using a variety of conventional thermogravimetric methods. Two peaks were found in the composite differential curves: the first peak close to 327 and the second peak at 408°C. The apparent activation energy values for the second peak decreased when fibre were treated. The addition of the jute fibres produced a slightly decrease in the thermal stability of the composites.

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The appearance of zarzuela in Hungary is entirely unknown in musicology. In the present study, I discuss the currently unchartered reception of the zarzuela El rey que rabió (first performed in Spain in 1891) by Ruperto Chapí (1851-1909), a Spanish composer of over one hundred stage pieces and four string quartets. Premièred as Az unatkozó király in Budapest seven years later in 1898, Chapí’s zarzuela met with resounding success in the Hungarian press, a fervour which reverberated into the early decades of the twentieth century. Emil Szalai and Sándor Hevesi’s skilful Hungarian translation, together with Izsó Barna’s appropriate adjustments and reorchestration, accordingly catered the work to Budapest audiences. Through analysis of hand-written performance materials of Az unatkozó király (preserved in the National Széchényi Library), alongside a detailed study of the Hungarian reception, the profound interest in Spanish music–particularly in relation to musical theatre–amongst the turn-of-the-century Hungarian theatre-going public is revealed. This paper explores how Az unatkozó király became a success in Hungary.

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