https://hdl.handle.net/20.500.12619/1053 Mon, 13 Apr 2026 14:46:57 GMT 2026-04-13T14:46:57Z https://hdl.handle.net/20.500.12619/45361 An application of derivative and continuous wavelet transforms to the overlapping ratio spectra for the quantitative multiresolution of a ternary mixture of paracetamol, acetylsalicylic acid and caffeine in tablets Özdemir, Abdil Quantitative multi resolution of tablets and ternary mixtures of paracetamol (PAR), acetylsalicylic acid (ASP) and caffeine (CAF) having strongly overlapping spectra was accomplished by two graphical transform methods as ratio spectra first derivative-zero crossing and ratio spectra-continuous wavelet transform-zero crossing (ratio spectra CWT-zero crossing) methods. In this study, ratio spectra derivative-zero crossing and ratio spectra CWT-zero crossing methods are based on the use of transformed signals of the ratio spectra and their calibration graphs were obtained by measuring the dA/dlambda and CWT amplitudes of the ratio spectra corresponding to zero crossing points. For the comparison purpose. PLS calibration method was applied to predict the content of the same mixtures containing the subject active Compounds. The obtained calibrations were tested by using the synthetic mixtures and standard addition technique and they applied to the simultaneous determination of PAR, ASP and CAF in commercial pharmaceutical preparation. The obtained results were statistically compared with each other as well as those obtained by HPLC method and they showed good agreement. (C) 2004 Published by Elsevier B.V. Sat, 01 Jan 2005 00:00:00 GMT https://hdl.handle.net/20.500.12619/45361 2005-01-01T00:00:00Z https://hdl.handle.net/20.500.12619/45362 UVRR spectroscopic studies of valinomycin complex formation in different solvents Özdemir, Abdil We investigated the complexation of valinomycin (VM) in different solvent environments with the aid of the UVRR spectroscopy. By probing the 206.5 and 229 nm excited Raman spectra, we showed that new bands are observed around 1700 and 1290 cm(-1). We assigned the 1700 cm(-1) band to the hydrogen bonded ester carbonyl stretching vibration. In a polar solvent, VM-K+ complexation shows significant intensity changes in amide and ester carbonyl stretching region. Because of the small amount of conformational interconversion, complexation has a negligible effect on other band intensities including, the amide III, CalphaH, and amide II. We also showed the effects of the solvent polarity on the solution conformation of VM. (C) 2004 Elsevier B.V. All rights reserved. Sat, 01 Jan 2005 00:00:00 GMT https://hdl.handle.net/20.500.12619/45362 2005-01-01T00:00:00Z https://hdl.handle.net/20.500.12619/45360 A kinetic study of metal complex dye sorption onto pine sawdust Özacar, Mahmut; Şengil, İsmail Ayhan The removal of metal complex dyes, Metal Complex Blue (MCB) and Metal Complex Yellow (MCY), from aqueous solutions by pine sawdust has been studied in single component sorption systems. The aim of this study was to understand the mechanisms that govern metal complex dyes removal and find a appropriate model for the kinetics of removal in a batch reactor. In order to investigate the mechanism of sorption and potential rate controlling steps, pseuso first- and second-order equations, intraparticle diffusion equation and the Elovich equation have been used to test experimental data. Kinetic analysis of the four models has been carried out for system variables-particle size and mass of sawdust, pH and initial dye concentration. The rate constants for the four models have been determined and the correlation coefficients have been calculated in order to assess which model provides the best fit predicted data with experimental results. Both pseudo second-order equation and the Elovich equation provide the best fit to experimental data. (C) 2004 Elsevier Ltd. All rights reserved. Sat, 01 Jan 2005 00:00:00 GMT https://hdl.handle.net/20.500.12619/45360 2005-01-01T00:00:00Z https://hdl.handle.net/20.500.12619/45359 (E)-9,10-Dihydro-9-methyl-9-nitro-10(trinitromethyl)anthracene Arslan, Mustafa The title compound, C16H12N4O8, was prepared by the photochemical reaction of 9-methylanthracene and tetranitromethane in dichloromethane. Intermolecula face-to-face pi-pi stacking interactions are present along the a axis. Sat, 01 Jan 2005 00:00:00 GMT https://hdl.handle.net/20.500.12619/45359 2005-01-01T00:00:00Z