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been grown by slow evaporation technique at room temperature. The changes in the FTIR, XRD, hardness parameters, and thermal stability have been studied. Experimental Crystal growth BTU crystals were grown

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thiourea complexes, viz., zinc thiourea sulphate, bis thiourea cadmium chloride, triallyl thiourea mercury bromide, thio semicarbazide crystallizes in noncentro symmetry structure, show second harmonic generation (SHG). TG–DTA as well as FTIR spectral

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structure analysis by fourier transform infrared spectroscopy (FTIR). Experimental Sixty biodiesel reactions were performed through transesterification from two different sources of triglycerides; using frying oil and fish

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. However, in recent years, the use of infrared spectroscopy as a method of characterisation of crystallinity has grown in prominence. In the case of PCL, one of the first and often cited studies concerned the study of a PCL/PVC blend system using FTIR

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most widely used techniques in the polymer industry for its characterization of polymers [ 21 – 23 ]. Recently, FTIR has also been applied to evaluate radiative heat transfer property of foams [ 24 ], films [ 25 ] or nonwovens [ 26 ]. In this article

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Abstract  

Urea-formaldehyde (UF) resins are the most used polycondensation resins today, in manufacturing particleboards. UF resins possess some advantages such as fast curing, good performance in the panel, water solubility and low price. However, the main chemical bonds of the UF resins macromolecules are hydrolysis sensitive. This causes low water and mositure resistance performance and subsequent formaldehyde release from the UF-bonded panels. A multitude of pathways have been explored for the improvement of UF resins’ behavior relating either to their synthesis procedure or application parameters during panel manufacture. In this study, two UF resins (a conventional and an innovative one produced at very low pH and temperature conditions) were analyzed for their specifications and characterized with TG-DTA technique in dynamic heating conditions and FTIR measurements both in their pre-polymer and cured state.

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of NO x by hydrocarbons. The detailed localization of Cu + ions was widely studied by the CO probe molecule adsorption using the FTIR, EXAFS, EPR, UV–Vis, microcalorimetry, and TPD techniques [ 15 – 27 ] assuming the presence of several

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Abstract  

Most studies report a depression of the glass transition temperature in thin polymer films. To gain insight into this behavior, we have simultaneously investigated the structure of materials and their thermal behavior by developing an ATR–FTIR–nano-differential scanning calorimeter (nanoDSC) hybrid instrument consisting of a ZnSe ATR crystal upon which the sample and a DSC-on-a-chip rests. FTIR spectra showed property changes with film thickness; nanoDSC did not. The relative absorbance of an IR peak at 797 cm−1 was found to correlate with aging time in thin films, suggesting that conformational structure of thin films is critical to their thermal behavior.

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Abstract  

Pyrolysis of sugarcane bagasse and coconut fiber was studied by thermal analysis in order to characterize their thermal behavior and to identify their constituents by the aid of their thermogravimetric curves and to determine their heat capacity by means of DSC. The Fourier Transform Infrared Spectrum (FTIR) was used to determine the main constituents present in both residues. The thermal degradation of sugarcane bagasse and coconut fiber presents two mass loss steps attributed to the release of humidity and to the decomposition of organic material (hemicellulose, cellulose and lignin). It was expected that the results of DSC analysis were almost the same for both types of biomasses.

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Abstract  

A single crystal of sodium and potassium cinnamates was grown by slow evaporation of methanol solution at room temperature. The effect of metals sodium and potassium on the electronic structure of cinnamic acid was studied. In this research many analytical methods such as FTIR, UV, second harmonic generation (SHG) and TG–DTA were used: The spectroscopic studies lead to conclusions containing the distribution of the electronic charge in molecule, the delocalisation of π electrons and the reactivity of metal complexes. The SHG efficiency is more pronounced in the presence of sodium and potassium dopant in the growth medium. Incorporation of sodium and potassium increase the thermal stability ensuring the suitability of material for possible non-linear optical (NLO) application up to 180 °C.

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