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promising natural fiber composites industry. Many studies have been conducted to address this problem and overcome this obstacle. Various fiber pre-treatments and coupling agents have been used to enhance the fiber-matrix interface. Bledzki et al. [ 1 ] have

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structure [ 18 , 19 ]. The synthesis of the copper ferrite was achieved by mechanical milling of the precursors oxides followed by annealing treatment [ 20 ]. This article presents results of the investigation of the influence of the heat treatments

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Introduction Heat treatment is a routine operation in food production since it effectively destroys microorganisms that cause spoilage in food, thereby increasing the shelf life of products. At the same time, high temperatures may have a negative

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nanotubes are still topics under discussion. Kasuga et al. [ 3 ] concluded that titania nanotubes were produced after hydrothermal reaction and washing the alkali-treated specimen with water followed by a further treatment with HCl. Zhang et al. [ 6 ] found

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Abstract  

The uptake of137Cs and90Sr/90Y onto Syrian bentonite has been studed, using batch and column tracer techniques in order to investigate its utilization for aqueous radioactive effluent treatment. Parameters influencing the percent uptake considered and studied in this work are: nuclide concentration, pH of the aqueous phase, heat treatment and particle size. Leaching experiments using natural sea and ground waters were carried out on bentonite/cement composites. They demonstrated the effectiveness of calcination and cement containment.

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Abstract  

H2SO4 and HCl processes accompanied by thermal treatments at different stages are described for the industrial extraction of alumina from lateritic clay minerals, especially from kaolinite, an important component of lateritic bauxites. The effects of calcination at high temperatures on the pretreatments of the raw lateritic materials, as well as on the thermal transformations of the products (salts) resulting from the acid treatments of lateritic bauxites are analyzed. Beside energetic considerations, separation methods of Al from Fe and from other lateritic-metallic components are emphasized in the extraction and purification processes. The mechanism of a controlled HCl-extracting treatment performed on iron-bearing kaolinite is described, as well as its characterization by IR and DTA ad hoc methods, enabling to distinguish between Al and Fe in the structure of lateritic kaolinite. The location and quantification of Al in the structure of lateritic goethite is also considered.

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Progress in Agricultural Engineering Sciences
Authors: István Dalmadi, Dávid Kántor, Kai Wolz, Katalin Polyák-Fehér, Klára Pásztor-Huszár, József Farkas, and András Fekete

., Berg, R. (2003) Combined high-pressure and thermal treatments for processing of tomato puree: evaluation of microbial inactivation and quality parameters, Innovative Food Science and Emerging Technologies , 4, 377

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Abstract  

Heat treatment of pipes was performed under industrial conditions at 580C in a dry protective gas containing a CO2–CO–H2–N2 mixture. A commercial adsorbent (733 kg) used for production ofthe gas removed 52.7 l of water in five h and 22.5 min. During the annealing of pipesoxidation and decarburization were not observed. The results were confirmed bymetallographic analysis. The values of enthalpy of water desorption (36.4–40.5 kJ mol–1) obtained by DSC and TG measurements were close to those of water evaporation(44.1 kJ mol–1). This suggests that the bonds between the water molecules andadsorbents were not of chemical but of physical nature.

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Journal of Thermal Analysis and Calorimetry
Authors: N. Ando, S. Tasaki, Y. Hato, C. Marumo, Y. Natsume, S. Ohmori, A. Ito, and K. Tanaka

Abstract  

The polyacenic semiconductive (PAS) material is a typical amorphous carbon prepared by pyrolysis of phenolformaldehyde resin, and is actually utilized as anode of high-capacity rechargeable batteries. In this work, change in the discharging amount of Li+ before and after heat-treatment of the PAS electrodes at the various doping level was examined in detail. As a result, the doped Li can be classified into two types: (i) heat-resistant Li-dopant (or Li-dopant with high diffusion coefficient) and (ii)heat-fragile Li-dopant (or Li-dopant with low diffusion coefficient). The latter Li-dopants are generated above the doping level of 30% ([Li]/[C]→0.3) and is considered to be the origin of high-capacity of PAS anode compared with that of graphite anode. This aspect is also supported by the ESR, 7Li-NMR, and XPS observation results.

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Abstract  

The mechanics of thermally-activated gaseous diffusion in polymers have long been studied for development of theoretical understanding of the interactive forces responsible for the non-linear nature of diffusion and the resultant enthalpic changes in the polymer. Methodologies and calculations have been developed in this work for treatment of experimental data for elimination of thickness-related anomalies in water vapor diffusion and for delineation of pressure effects. Linearized data for different polymer thicknesses and the attendant internal thermal effects have been generated by using calculated single molecule diffusion values. Equally linear data are obtained for different pressures by the use of a graphical method from which identical diffusion values are obtained, independent of material thickness and external pressure. True comparisons and classification of polymers as to their diffusivities are thus possible for development of barrier materials for food and drug packaging and for protective encapsulation of electronic devices. Results will be reported for three structurally different polymers.

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