Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8651
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Article Modelling the Latex Spreading on Clay(Chiminform Data S A, 2014) Al-Turaif, Hamad A.; Baleanu, Dumitru; Baleanu, Dumitru; MatematikIn this manuscript a model was proposed in order to predict the extent of the latex spreading on clay pigment. The results from Scan Electron Microscopy (SEM) and X-ray Photoelectron Spectroscopy (XPS) were used to evaluate the predicted results. A good agreement of the predicted results was found.Article Citation - WoS: 8Citation - Scopus: 8Determination of Salicin Content of Some Salix L. Species by Hplc Method(Chiminform Data S A, 2007) Guvenc, Aysegul; Baleanu, Dumitru; Arihan, Okan; Altun, M. Levent; Dinc, Erdal; Baleanu, Dumitru; MatematikIn this paper, we find the salicin content of the nine species of Salix L from the province of Ankara, Turkey, namely Salix triandra, S. alba, S. excelsa, S. fragilis, S. babylonica, S. caprea, S. cinerea, S. pseudomedemii and S. amplexicaulis. A simple HPLC method was applied to the determination of Salicin of these nine species in barks and leaves of female and male. Chromatographic separation was carried out by a mobile phase consisting of bidistilled water, tetrahydrofuran and ortho-phosphoric acid (97.7: 1.8: 0.5) (v/v/v). The salicin amount of these samples was analyzed by measuring the peak area at the wavelength, 270 nm. A reversed phase phenyl column (250 x 4.6mm, 5 mu m) was used and flow rate was set to 1 ml/min. in an isocratic elution. The results provided 6 HPLC method was found in agreement with those indicated by European Pharmacopoeia. It was observed that S. babylonica female bark sample possess the highest salicin content (2.675), while S. caprea female bark (0.058) has the lowest salicin content as w/w (%).Article Citation - WoS: 7Citation - Scopus: 6Simultaneous Determination of Chlorotetracycline and Benzocaine in Bolus by Chemometric Methods(Chiminform Data S A, 2007) Dinc, Erdal; Baleanu, Dumitru; Kanbur, Murat; Baleanu, Dumitru; MatematikTwo chemometric methods were applied to the simultaneous determination of chlortetracycline (CTC) and benzocaine (BC) in their binary mixture. The methods involve multivariate calibration based on principal least-squares (PCR) and partial least-squares (PLS) regressions. A concentration set consisting of binary mixtures of CTC and BC in 13 different combinations were randomly prepared in 0,011 M HCl. Both multivariate calibration models were constructed by using the relationship between the concentration set and its corresponding absorption data in the spectral region of 200-305 nm, The accuracy and the precision of the methods were validated by analyzing synthetic mixtures containing investigated drugs. The recovery results obtained by applying PCR and PLS calibrations to artificial mixtures were found between 100.2 and 101.0%. Data treatments, regressions and statistical analysis were performed by using the Microsoft EXCEL and PLS toolbox 3.5 in Matlab 7.0 software. Satisfactory results for both artificial and commercial veterinary samples were obtained. The experimental results from two chemometric methods were compared with each other.Article Citation - WoS: 4Citation - Scopus: 4Discrete and Continuous Wavelet Transforms for the Multicomponent Determination of Sunset Yellow and Tartrazine in Their Soft Drink Powders(Chiminform Data S A, 2006) Dinç, E; Baleanu, Dumitru; Baleanu, D; Üstündag, Ö; Aboul-Enein, HY; MatematikThe multicomponent quantitative resolution of the binary mixtures containing, sunset Yellow (SN) and tartrazine (TR) without any pre-chemical treatment, in the presence of the overlapping signals was accomplished by the simultaneous use of the discrete and the continuous wavelet transform (CWT) followed by a zero crossing technique. We propose G transformation approach of signals in wavelet domain, based on both one-dimensional CWT and zero-crossing technique for obtaining a higher resolution of the binary mixtures. The application of this approach contains three steps: firstly, UV-recorded spectra were transferred into the wavelet domain and were subject to the one-dimensional discrete wavelet transform for obtaining an appropriated de-noising signal; secondly, CWT was applied on the de-noising signal and a new transformed signal was obtained so that it contains many zero-crossing points and higher peaks.; thirdly, a zero-crossing technique was applied to the transformed signal obtained in step two, The calibration graphs were drawn by choosing a one-dimensional continuous family, namely, Symlets2 (SYM2) and Gauss3 (GAUS3) followed by a zero-crossing technique. The quantitative analysis of the commercial product containing the above colorants was carried out by using this approach and successful results were obtained.Article Citation - WoS: 3Citation - Scopus: 5Simultaneous Determination of Quinapril and Hydrochlorothiazide in Tablets by Ratio Spectra Derivative Spectrophotometric and Chemometric Methods(Chiminform Data S A, 2007) Dinc, Erdal; Baleanu, Dumitru; Altynoz, Sacide; Baleanu, Dumitru; MatematikSimultaneous determination of quinapril (QA) and hydrochlorothiazide (HCT) in tablets were accomplished by ratio spectra first order derivative spectrophotometry (graphical method) and chemometric method (numerical method). Both methods do not require any chemical separation step. In the application of two analytical methods, the absorption spectra in the working range of 4.0-20.0 mu g/mL QA and 2.5-12.5 mu g/mL HCT were plotted in the wavelength range of 210-350 nm. In the graphical approach, the absorption spectra of QA and its binary mixtures in the selected spectral range of 210-280 nm were divided by the standard spectrum of 10 mu g/ mL HCT and their absorption spectra were obtained. In the similar way, the ratio spectra of HCT in the wavelength region of 210-350 nm were also obtained by using the standard spectrum of 12 mu g/mL QA. First derivative of the ratio spectra obtained in the above steps were calculated by Delta lambda=5 nm interval for both drugs. Calibration equation functions were obtained by measuring (he ratio spectra derivative amplitudes of the minima at 219.9 nm for QA and 283.2 nm for HCT in the above mentioned spectral ranges for each drug. In the numerical method, the critical wavelengths corresponding to maximum points at 213.0 nm for QA and 220.0 nm for HCT in the zero-order absorption spectra were selected to construct the least squares calibration (CLS). Both graphical and numerical methods developed in this study were completely validated and applied to the quantitative analysts of tablets containing QA and HCT The results obtained from the developed methods were compared with each other as well as to those obtained by classical derivative spectrophotometry, which have different experimental conditions than the previous derivative method, and the difference was not observed statistically significant.Article Citation - WoS: 5Citation - Scopus: 5Spectral Continuous Wavelet Transform for the Simultaneous Spectrophotometric Analysis of a Combined Pharmaceutical Formulation(Chiminform Data S A, 2009) Dinc, Erdal; Baleanu, Dumitru; Baleanu, Dumitru; MatematikContinuous wavelet transform (CWT) combined with zero crossing technique was proposed for the simultaneous spectrophotometric determination of telmisartan (TMS) and hydrochlorothiazide (HCT) in their binary mixtures without using a chemical pretreatment. This new hybrid analytical approach is based on the application of the CWT method to the absorption spectra of the analytes and their samples. In the signal analysis, Gaussian (GAUS3) with order 3 and BiorSplines (BIOR1.2) with 1.2 order were found to be suitable for the quantitative spectral resolution of TMS and HCT in samples. These hybrid approaches were named as GAUS3-CWT and BIOR1.2-CWT The validation of the CWT signal processing methods was carried out by using various binary mixtures of the analytes. The amounts of TMS and HCT in tablets were successfully determined by using the proposed GAUS3-CWT and BIOR1.2-CWT tools.Article Simultaneous Determination of Hydrochlorotiazide and Olmesartan Modoxomil in a Binary Mixture by the Calibrations of the Spectral Linear Regression Equations(Chiminform Data S A, 2012) Dinc, Erdal; Baleanu, Dumitru; Buker, Eda; Baleanu, Dumitru; MatematikTwo new approaches were proposed for the quantitative analysis of the commercial samples consisting of hydrochlorotiazide (HCT) and olmesartan modoxomil (OLM). The proposed bivariate calibration (BC) and multivariate linear regression calibration (MLRC) methods are based on the simultaneous use of the linear regression equations for each compound. The UV absorption spectra of calibration solutions in the linear concentration range of 1.0-16.0 mu g/mL for both HCT and OLM were recorded between the 200-300 nm wavelength regions. The individual linear regression equations of the subjected compounds were obtained by using the relationships between the concentration and absorbance values at the 62 wavelength points with the interval of 1.0 nm from 218 nm to 279 nm. The BC and MLRC model based linear regression equations were validated by analyzing the binary mixture samples containing HCT and OLM in the different concentration compositions. The proposed BC and MLRC approaches were found to be accurate, precise and rapid for the simultaneous determination of HCT and OLM in combined dosage form.Article On the Analysis of Data Emerging in Non-Linear and Complex Systems Comparison of Two X-Ray Prony Spectra(Chiminform Data S A, 2015) Nigmatullin, Raul R.; Baleanu, Dumitru; Khramov, A. S.; Kiyamov, A. G.; Fatkhullin, B. F.; Machado, J. T.; Baleanu, Dumitru; MatematikNew arguments proving that successive (repeated) measurements have a memory and actually remember each other are presented. The recognition of this peculiarity can change essentially the existing paradigm associated with conventional observation in behavior of different complex systems and lead towards the application of an intermediate model (IM). This IM can provide a very accurate fit of the measured data in terms of the Prony's decomposition. This decomposition, in turn, contains a small set of the fitting parameters relatively to the number of initial data points and allows comparing the measured data in cases where the "best fit" model based on some specific physical principles is absent. As an example, we consider two X-ray diffractometers (defined in paper as A-("cheap') and B-("expensive') that are used after their proper calibration for the measuring of the same substance (corundum a-Al20). The amplitude-frequency response (AFR) obtained in the frame of the Prony's decomposition can be used for comparison of the spectra recorded from (A) and (B) -X-ray diffractometers (XRDs) for calibration and other practical purposes. We prove also that the Fourier decomposition can be adapted to "ideal" experiment without memory while the Prony's decomposition corresponds to real measurement and can be fitted in the frame of the I M in this case. New statistical parameters describing the properties of experimental equipment (irrespective to their internal "filling") are found. The suggested approach is rather general and can be used for calibration and comparison of different complex dynamical systems in practical purposes.Article Citation - WoS: 2Citation - Scopus: 3An Application of Principal Component Analysis - Artificial Neural Network for the Simultaneous Quantitative Analysis of a Binary Mixture System(Chiminform Data S A, 2009) Dinc, Erdal; Baleanu, Dumitru; Sen Koktas, Nigar; Köktaş, Nigar; Baleanu, Dumitru; Kökias, Nigar Şen; MatematikArtificial neural networks (ANNs) based on the use of principal components and the original absorbance data were proposed for the simultaneous quantitative analysis of amlodipine (AML) and atorvastatin (ATO) in tablets. A concentration set of mixtures containing ATO and AML in different concentration composition between 0.0-20.0 mu g/mL was prepared in methanol. The measured absorbance data matrix for the concentration data set was obtained and the principal components were extracted. In the next step five principal components were selected as an input data for the artificial neural network. This combined approach was named principal components-artificial neural network (PCA-ANN). The same problem was solved by using the application of the artificial neural network to the original absorbance data matrix. This approach was denoted as ANN. The classical ANN approach was used as a comparison method. Both PCA-ANN and ANN methods were tested by analyzing various synthetic mixtures corresponding to the validation set of AML and ATO compounds. The proposed methods were successfully applied to the quantitative analysis of the commercial tablets and a coincidence was reported between the proposed methods.Article Citation - WoS: 1Citation - Scopus: 1Ultra Performance Liquid Chromatography for the Rapid Determination of Allura Red in a Commercial Liquid Drink(Chiminform Data S A, 2011) Dinc, Erdal; Baleanu, Dumitru; Buker, Eda; Baleanu, Dumitru; MatematikA new ultra performance liquid chromatographic (UPLC) method was developed for the rapid determination of allura red in a commercial liquid drink. Chromatographic separation and quantitation of allura red were accomplished on an Acquity UPLC (TM) BEH C(18) (50 mm x 2.1 mm, 1.7 mu m) column system using an isocratic elution with a mobile phase consisting of acetonitrile and acetic acid with 3 % triethylamine (20:80: v/v) at a constant flow rate, 0.4 mL/min. Chromatographic calibration graph for allura red in the linear concentration range of 1.0-10.0 mu g/mL was calculated by using the linear least square regression analysis based on the relationship between the concentration and the peak area with photodiode array detection at the wavelength 510 nm. The UPLC method was validated by using the standard addition technique and successfully applied to the UPLC quantitation of the commercial liquid drinking samples. We conclude that a good agreement of UPLC quantitation results was reported.