Matematik Bölümü Yayın Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/413
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Article Citation - WoS: 16Citation - Scopus: 16Comparative Application of Wavelet Approaches To Absorption and Ratio Spectra for the Simultaneous Determination of Diminazene Aceturate and Phenazone in Veterinary Granules for Injection(Govi-verlag Pharmazeutischer verlag Gmbh, 2005) Dinç, E; Baleanu, Dumitru; Kanbur, M; Baleanu, D; MatematikA comparison of two wavelet approaches, Daubechies and reverse Biorthogonal, is described for the quantitative resolution of a binary mixture of diminazene aceturate (DIMA) and phenazone (PHE) in veterinary granules for injection without any chemical separation. These two approaches were specified as db4 (a = 180) and rbior3.7 (a = 125) respectively, after testing the signal analysis parameters for the overlapping absorption spectra and ratio spectra. In the first step db4 (a = 180) was applied to the original absorbance data vector of DIMA and PHE. In the second step rbio3.7 (a = 125) was applied to the ratio spectra data vectors of DIMA using the divisor PHE. The same approach was also subjected to the ratio spectra of PHE using the divisor DIMA. The db4 (a = 180) and rbior3.7 (a = 125) calibration graphs were constructed using the transformation values obtained in the wavelet domain. In the method validation, the wavelet calibration functions were tested using synthetic mixtures and the standard addition technique. The simultaneous quantitative analysis of DIMA and PHE in the commercial veterinary preparation was achieved by the elaborated methods. The assay results were compared with each other and good agreement was observed.Article Citation - WoS: 4Citation - Scopus: 5One-Dimension Continuous Wavelet Resolution for the Simultaneous Analysis of Binary Mixture of Benazepril and Hydrochlorothiazide in Tablets Using Spectrophotometric Absorbance Data(Editura Academiei Romane, 2004) Dinç, E; Baleanu, Dumitru; Baleanu, D; MatematikOne-dimensional continuous wavelets transform (CWT) followed by a zero-crossing technique were applied to the quantitative resolution of a binary mixture of benazepril (BE) and hydrochlorothiazide (HCT) in two commercial tablet formulations. UV-spectra in the range of 210.1-300.0 nm, were recorded and transferred as vectors having 900 components into MATLAB 6.5. The analyzed signals corresponding to the above vectors were subjected to three CWT families, namely, Mexican (MEX), Haar (HA) and Daubechies3 (DAUB3) wavelets. For these three families a detailed analysis procedure was performed and we retained only those parameters creating many zero-crossing points for transformed signals. At locations where the wavelet transform of one component vanishes, the value of the mixture's transformed signal is due only to the other component. This allows rapid approximate determination of the concentrations. The above three wavelet bases provided reliable results of the analysis of the mixtures containing BE and HCT in two pharmaceutical tablet formulations.Article Citation - WoS: 5Citation - Scopus: 9Combined Application of Continuous Wavelet Transform-Zero Crossing Technique in the Simultaneous Spectrophotometric Determination of Perindopril and Indapamid in Tablets(Soc Brasileira Quimica, 2009) Pektas, Goezde; Baleanu, Dumitru; Dinc, Erdal; Baleanu, Dumitru; Pektag, Gözde; MatematikSignal processing methods based on the combined use of the continuous wavelet transform (CWT) and zero-crossing technique were applied to the simultaneous spectrophotometric determination of perindopril (PER) and indapamide (IND) in tablets. These signal processing methods do not require any priory separation step. Initially, various wavelet families were tested to identify the optimum signal processing giving the best recovery results. From this procedure, the Haar and Biorthogonal 1.5 continuous wavelet transform (HAAR-CWT and BIOR 1.5-CWT, respectively) were found suitable for the analysis of the related compounds. After transformation of the absorbance vectors by using HAAR-CWT and BIOR 1.5-CWT, the CWT-coefficients were drawn as a graph versus wavelength and then the HAAR-CWT and BIOR 1.5-CWT spectra were obtained. Calibration graphs for PER and IND were obtained by measuring the CWT amplitudes at 231.1 and 291.0 rim in the HAAR-CWT spectra and at 228.5 and 246.8 nm in BIOR 1.5-CWT spectra. respectively. In order to compare the performance of HAAR-CWT and BIOR 1.5-CWT approaches, derivative spectrophotometric (DS) method and HPLC as comparison methods, were applied to the PER-IND samples. In this DS method, first derivative absorbance values at 221.6 for PER and 282.7 nm for IND were used to obtain the calibration graphs. The validation of the CWT and DS signal processing methods was carried out by using the recovery study and standard addition technique. In the following step, these methods were Successfully applied to the commercial tablets containing PER and IND compounds and good accuracy and precision were reported for the experimental results obtained by all proposed signal processing methods.Article Citation - WoS: 13Citation - Scopus: 14Continuous Wavelet Transformation Applied To the Simultaneous Quantitative Analysis of Two-Component Mixtures(Govi-verlag Pharmazeutischer verlag Gmbh, 2004) Dinç, E; Baleanu, Dumitru; Baleanu, D; Üstündag, Ö; Aboul-Enein, HY; MatematikIn this paper we developed a graphical method based on Haar (HA) and Mexican (MEX) one-dimensional continuous wavelet transforms and we applied it to a mixture of hydrochlorothiazide (HCT) and spironolactone (SP) in the presence of strongly overlapping signals. Keeping in mind to obtain an appropriately transformed spectrum, we tested several values of the scaling parameter a and the point number of the analysed spectrum in the concentration range of 2-22 mug/ml for both active compounds. The optimal values of the scale parameters and the corresponding frequencies were found to be a = 32 and 0.031 for HA and a = 30 and 0.008 for MEX corresponding to 400 points. HA and MEX methods based on a zero crossing technique were applied to the analysed signal and their regression lines at the selected points were obtained. The validation of the above methods was carried out by analysing different synthetic mixtures containing HCT and SP. MATLAB 6.5. Software was used for one-dimensional wavelet analysis and the basic concepts about wavelet method were briefly explained. The method developed in this paper is rapid, easy to apply, inexpensive and is suitable for analysing the overlapping signals of compounds in their mixtures without any chemical pre-treatment.Article Citation - WoS: 6Citation - Scopus: 8Simple Mathematical Resolution for Binary Mixture of Oxfendazole and Oxyclozanide in Bolus by Bivariate and Multivariate Calibrations Based on the Linear Regression Functions(Editura Acad Romane, 2008) Dinc, Erdal; Baleanu, Dumitru; Baleanu, Dumitru; Tokar, Ferdi; MatematikTwo simple mathematical approaches were proposed for the simultaneous determination of oxfendazole (OXF) and oxyclozanide (OXY) in their synthetic binary mixtures and commercial veterinary formulation without requiring a priory separation step. One of these mathematical calibration techniques is called the bivariate calibration (BSC) based Oil four linear regression functions obtained at the wavelengths (230nm and 305 nm) with two single-component regression equations for each compound. The selection of the above mentioned wavelengths was performed by using the Kaiser technique. In the second mathematical approach, the multivariate spectral calibration (MSC) was constructed by a combined use of 42 linear regression functions consisting of 21 single linear regression equations for each compound at 21-wavelength set in between 230 and 330 run with intervals of Delta lambda=5nm. These two mathematical approaches were validated and applied to the quantitative analysis of the commercial veterinary formulation containing OXF and OXY. In this study successful results for the synthetic and real samples were reported.Article Chemometric Calibration Based on the Wavelet Transform for the Quantitative Resolution of Two-Colorant Mixtures(Editura Acad Romane, 2005) Baleanu, Dumitru; Dinç, E; Baleanu, D; Taş, Kenan; Üstundag, O; Tas, K; MatematikIn this study we proposed a wavelet transform (WT) followed by two chemometric techniques for the quantitative determination of sunset yellow (SUN) and tartrazine (TAR) in their market samples. Absorbances of the concentration set formed by TAR and SUN mixtures were measured between 335-575 nm at 480 points with 0.5 nm intervals and their absorbance values as absorbance data vectors were transferred into the wavelets domain. A continuous wavelet transform (CWT) was applied, to the absorbance data. The obtained CWT-coefficients (x-block) and concentration set (y-block) were used for the construction of the principal component regression (VCR) and partial least squares (PLS) calibrations. Good results were reported for the application of the combining wavelets and chemometric tools in the determination of colorants in samples.Article Citation - WoS: 5Citation - Scopus: 6Spectrophotometric Simultaneous Analysis of Two-Component Mixture by Bivariate and Multivariate Calibrations Using the Linear Regression Functions(Editura Acad Romane, 2008) Dinc, Erdal; Baleanu, Dumitru; Arslan, Fahrettin; Baleanu, Dumitru; MatematikSpectral bivariate calibration (SBC) and spectral multivariate calibration (SMC) approaches based on the linear regression models were applied to the simultaneous determination of chlorzoxazone (CHL) and paracetamol (PAR) in tablets. SBC model was constructed by using four linear regression functions at two-wavelength set (220 and 244 nm) selecting two optimal wavelengths among 25 wavelength points. SMC model for cacti compound was obtained by using of 50 linear regression functions at 25 wavelength points in the spectral range 220-293 nm without selecting any optimal wavelength points. SBC and SMC was validated by using an independent validation set containing CHL-PAR combinations in the linear concentration range. The recovery results were found between 100.6% and 102.6% for both proposed appropaches, therefore we Conclude that a successuful method application was reported. The results obtained in this study clearly indicate that the proposed SBC and SMC approaches are suitable to be used for the quality control and routine analysis of the commercial tablets containing CHL and PAR compounds.Article Citation - WoS: 12Citation - Scopus: 15Determination of Guaifenesin and Dextromethorphan in a Cough Syrup by Hplc With Fluorometric Detection(Editura Academiei Romane, 2006) Ozdemir, Abdil; Baleanu, Dumitru; Aksoy, Halil; Dinc, Erdal; Baleanu, Dumitru; Dermis, Saadet; MatematikA practical high-performance liquid chromatographic method with fluorometric detection for the determination of guaifenesin and dextromethorphan in cough syrup is described. The developed method contains simple, accurate and rapid sample preparation steps for the separation and simultaneous determination of active compounds in samples with existence of other excipients. Amilorid (AM) was used as an internal standard (IS) that has a fluorescence character in the working wavelength region. A good chromatographic separation of two drugs and IS was achieved on a Waters Symmetry(R) C18 Column 5 mu m 4.6 x 250 mm with mobile phase consisting of phosphate buffer (0.2 M, pH=2), acetonitrile and methyl alcohol (v/v, 62:23:15). Eluents were monitored by fluorescence detection at the excitation and emission wavelengths of 277 and 588 nm, respectively. Under the described conditions, the obtained calibration graphs are linear over the concentration range of 0.054.2 and 1.2-2.4 mg/mL for dextromethorphan and guaifenesin, respectively and the regression coefficients were greater than 0.999. The validation study was carried out fulfilling the ICH guidelines in order to prove that the new analytical method meets the fundamental criteria including selectivity, linearity, precision, accuracy and sensitivity.Article Citation - WoS: 19Citation - Scopus: 18A New Application of Chemometric Techniques To Hplc Data for the Simultaneous Analysis of a Two-Component Mixture(Taylor & Francis inc, 2005) Üstündag, Ö; Özdemir, A; Baleanu, D; Dinç, EA new chemometric approach using high performance liquid chromatography (HPLC) with photodiode array (PDA) detection was developed and applied to the simultaneous determination of enalapril maleate (EA) and hydrochlorothiazide (HCT) in tablets. Chernometric calibration techniques, classical least squares (CLS), principle component regression (PCR), and partial least squares (PLS) were subjected to the peak area at multiwavelength PDA detector responses. The combination of HPLC and chernometric calibration techniques was called HPLC-CLS, HPLC-PCR, and HPLC-PLS. For comparison purposes, the HPLC method called classical HPLC method was used for the confirmation of the results obtained from combined HPLC-chemometric calibration techniques. A good chromatographic separation between two drugs and internal standard (IS) was achieved using a Waters Symmetry (R) C 18 Column 5 mu m 4.6 x 250 mm and a mobile phase consisting of 0.2M acetate buffer and acetonitrile (v/v, 60:40). The multiwavelength PDA detection was done at 230 (A), 240 (B), 250 (C), 250 (D), 240 (E) nm wavelengths, and peak area was recorded for the concentration set in the mobile phase. Three HPLC-chemometric calibrations and a classical-HPLC method were tested by analyzing the synthetic mixture of EA and HCT in the presence of losartan potassium (IS). The proposed methods were applied to real samples containing the present two drugs. The obtained results were statistically compared with each other.Publication About fractional calculus of singular Lagrangians(IEEE, 2004) Baleanu, DumitruIn this paper the solutions of the fractional Euler-Lagrange equations corresponding to singular fractional Lagrangians were examined. Despite of the complexity of solutions in the fractional case the gauge classical symmetry was preserved. Four examples of fractional singular Lagrangians were analyzed in details.