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The complex [Cu(hydet-en)2].(tpht) synthesized is characterized by single crystal X-ray determination, FT-IR spectroscopy, UV-Vis spectroscopy, thermogravimetric analysis and elemental analysis (tpht=dianion of terephthalic acid, hydet-en=N-(2- hydroxyethyl)ethylenediamine). While each hydet-en ligand coordinates to copper metal as bidentate, the tpht2-anion is freely available in the unit cell. Copper center has a square plane geometry. In the square geometry, the equatorial plane of the complex is composed of primary and secondary amine groups of hydet-en ligands. Monomers are bonded with O-H--O and N-H--O hydrogen bonds to form a supramolecular structure. FT-IR investigation of the complex was performed in the middle IR region. The vibrations of the complex were focused mainly considering the characteristic vibrations of terephthalic acid and N-(2- hydroxyethyl)ethylenediamine ligands. Thermal behaviour of the complex was followed using TG, DTA and DTG techniques. [ABSTRACT FROM AUTHOR]

Copyright of Firat Universitesi Sağlik Bilimleri Tip Dergisi is the property of Firat Universitesiu, Saglik Bilimleri Enstitusu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of extractives on the thermal behavior of Liquidambar orientalis Mill. (storax) wood is studied using thermogravimetric analysis (TGA). To evaluate the effects of polar and apolar extractives on the thermal behavior of wood, sawdust samples from the heartwood of L. orientalis are extracted with either cold water (48 h), hot water (48 h), or ethanol/toluene (1:2 v/v) (6 h) prior to thermal analysis. Thermogravimetry (TG) curves show that polar and apolar extractives promote char formation, increase the amount of residue, and improve the thermal behavior of L. orientalis wood. In addition, derivative thermogravimetry (DTG) curves demonstrate that thermal degradation of un-extracted and cold water-extracted wood samples occurs in a single step, while a two-step degradation pattern is seen for hot water- and ethanol/toluene-extracted wood samples. It is also observed that first degradation reactions in hot water and ethanol/toluene-extracted wood samples occur faster than those in unextracted and cold water-extracted wood samples. Although there are approximately half the number of extracted apolar compounds compared to polar compounds, the removal of both types of compounds affect the thermal properties of L. orientalis wood to the same degree. It is thus deduced that apolar extractives significantly affect the thermal behavior of L. orientalis wood.

Copyright of Adiyaman University Journal of Science & Technology / Adıyaman Üniversitesi Fen Bilimleri Dergisi is the property of Adiyaman University, Institute of Science / Adiyaman Universitesi Fen Bilimleri Enstitusu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fly ash which is a by-product of coal-fired power stations has been used as filler in different polymeric materials for different purposes. Since the chemical composition and the size of fly ash may vary depending on the coal type and combustion, properties of fly ash should be examined before the incorporation of fly ash into polymeric materials. In this study, two fly ashes which have different chemical compositions are used as filler in rigid polyurethane foams. The fly ashes were added in 5 %, 10 %, 15 % and 20 % in the total mass. The morphology of polyurethane foam cells was observed by using scanning electron microscopy and the effects of two different fly ashes on the thermal conductivity, the compressive strength, thermal stability and flammability of rigid polyurethane foams were investigated. Experimental results indicated that fly ash addition into rigid polyurethane foam has no negative effects on thermal conductivity of the materials; however it caused decreasing in the compression strength within the acceptable limits. In addition, it was determined that the foam materials filled with the fly ash containing high amount of SiO2 shows better fire resistance and thermal stability. [ABSTRACT FROM AUTHOR]

A pyrolysis study of furniture plant waste dusts is carried out under nitrogen flow rate of 10 ml/min. and heating rate of 10 ºC/min. at between 25-900 ºC in a TGA equipment. As a result of the pyrolysis of waste dusts, three region were determined on thermographs. Regression constants for the different theorical model equations that representing degradation were calculated by Coast-Redfern method. And according to regression coefficients, kinetic model which the best representing degradation, was determined. In the study, the kinetic parameters were determined for the second and third decomposition steps, separately. Best model equations representing degradation for total reaction, second degradation step that hemicellulose and cellulose degraded, third degradation step that lignin degraded was found to be chemical kinetic F(3) equation, Ginstling-Brounshtein (D4) and Jander (D3) equations and chemical kinetic F(3) equation, respectively. By using best model equations representing degradation, activation energies and ln (A/min-1) were determined to be 77.54-82.32 kJ/mol and 10.45-11.60, respectively for second degradation step that hemicellulose and cellulose degraded and 52.40 kJ/mol and 5.07 same respectively for third degradation step that lignin degraded. Kinetic parameters were found to be 54.89 kJ/mol, 9.33 for the total reaction. [ABSTRACT FROM AUTHOR]