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Böhm, A., Kaiser, I., Trebstein, A. & Henle, T. (2005): Heat-induced degradation of inulin. Eur. Fd Res. Technol. , 220 , 466–471. Henle T. Heat-induced degradation of inulin

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natural polymer from renewable resources, obtained from shell of shellfish, and a waste product of the seafood industry. It has a good biocompatibility property and degradable by enzymes to become oligosaccharide that can be easily absorbed. It forms an

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detected active ingredient. EAVPT Congress, Budapest, Abstracts, p. 291. Somlyay, I., Hidasi, Gy. and Várnagy, L. (1989): Degradation of Nevifosz 50 EC in pheasant embryos (in Hungarian). IVth Vet. Tox. Conf., Kaposvár. Summaries

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Iron polymethacrylate was synthesized by free radical solution polymerization of methacrylic acid, followed by replacement of the carboxylic proton with iron. Thermal volatilization analysis and thermogravimetry were used to study its thermal stability from ambient temperature up to 500oC. The results reveal that ferric oxide is left as residue at the end of the thermal degradation experiments.

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Abstract  

The process of thermal degradation of poly(vinyl chloride)/poly(methyl methacrylate-butadiene-styrene) (PVC/MBS) blends was investigated by means of isothermal thermogravimetry in nitrogen. The total mass loss was determined after 120 min. The kinetic parameters of the degradation process were determined by applying two kinetic models: the model which assumes autocatalytic degradation (Prout-Tompkins) and the model of two-dimensional diffusion. It was established that the thermal degradation at lower degrees of conversion (α<0.20) was well described by the former model, but the latter model was applicable at higher degrees of conversion. The thermal stability of blends at a certain temperature of isothermal degradation depends on the blend composition and the shell/core ratio in MBS, and on the adhesion in the boundary layer in PVC/MBS blends.

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): Teratogenicity testingofpesticides onbirdfetuses . Hung. Agr. Res. 2 , 30 – 33 . Várnagy , L. ( 1999 ): Degradation of some pesticides in avian embryos . Acta Vet. Hung. 47

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Abstract  

The synthesis of conducting polymers based on m-nitroaniline, m-chloroaniline and m-aminophenol by aniline initiated ammonium peroxydisulfate oxidation, has been attempted. The IR spectra of the polymers have been studied. Thermogravimetric analysis of the conducting polymers has been followed using a computer analysis method LOTUS PACKAGE, developed by us for assigning the degradation mechanism. A number of equations have been used to evaluate the kinetic parameters. The mechanism of degradation of the conducting polymers has been explained on the basis of their kinetic parameters.

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Abstract  

The thermal degradation of cotton cellulose treated with chemical mixtures containing P and N was studied by thermal analysis, infrared spectroscopy, Char yield and limiting-oxygen-index (LOI). Our experiments demonstrated the following facts. The temperatures and activation energies of pyrolysis were lower for cotton cellulose treated with flame retardants than those for untreated samples and the values of Char yield and LOI were greater for treated cotton than those for untreated one.

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Abstract  

A novel PMR polyimides (TMBZ-15) based on substituted benzidines is examined and compared to state-of-the-art PMR-15. The mechanism for the thermal decomposition of two specific PMR polyimides is obtained using TG/FTIR/MS techniques. In order to verify the pathway of polyimide degradation, a pyrolysis/GC-MS technique was employed to evaluate the organic degradation products, particularly the larger components that are destroyed in traditional TG/MS. A proposed degradation mechanism involves two main stages of decomposition, each of which produce a variety of products. The first group includes aromatic hydrocarbons, aromatic amines and nitriles, which correspond to partial fragments of polymer chains. The second group consists largely of fluorene, naphthalene and phenanthrene, which are attributed to the isomerization, rearrangements and cyclizations of the aforementioned pyrolyzates at high temperature.

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Abstract  

Thermogravimetric analysis (TG) was used in this work to study the degradation kinetics of industrial PVC plastisols. In order to model the pyrolitic degradation of plastisols in nitrogen, a kinetic model based on phenomenological considerations was developed. Two different processes were observed during the first degradation stage. The model parameters, such as activation energies and pseudo orders of reaction, were calculated using a non-linear regression analysis. The model developed was able to describe the degradation behaviour both in isothermal and in dynamic modes. The results of such analysis were applied to obtain long-term data from short-term experiments as an engineering approach to evaluate the thermal resistance of plastisols.

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