Browsing by Author "Baleanu, D"
Now showing 1 - 20 of 39
- Results Per Page
- Sort Options
Article A new application of chemometric techniques to HPLC data for the simultaneous analysis of a two-component mixture(Taylor & Francis inc, 2005) Dinç, E; Baleanu, Dumitru; Üstündag, Ö; Özdemir, A; Baleanu, D; 56389A 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.Article A zero-crossing technique for the multidetermination of thiamine HCl and pyridoxine HCl in their mixture by using one-dimensional wavelet transform(Elsevier, 2003) Dinç, E; Baleanu, Dumitru; Baleanu, D; 56389A new zero-crossing technique based on one-dimensional wavelet transform (WT) was developed and applied on a commercial vitamin product and binary mixtures containing thiamine HCl and pyridoxine HCl in the presence of the interference of the analysed signals. We selected from the data of the UV-Vis absorption spectra a signal consisting of 1150 points corresponding to the concentration range 8-32 mg/ml for both vitamins and we subjected it to one-dimensional continuous WT Mexican (MEXICAN) and Meyer (MEYER). Since the peaks of the transformed signals were bigger than original ones a zero crossing technique was applied to obtain the regression equations. The validity of Beer-Lambert law was assumed for the transformed signals. An appropriate scale setting was choosing to obtain an alternative calibration for each method. The basic concepts about wavelet method were briefly explained and MATLAB 6.5 software was used for one-dimensional wavelet analysis, The obtained results were successfully compared among each other and with those obtained by other literature methods. The developed method is rapid, easy to apply. not expensive and suitable for analysing of the overlapping signals of compounds in their mixtures without any chemical pre-treatment. (C) 2003 Elsevier Science B.V. All rights reserved.Conference Object About fractional supersymmetric quantum mechanics(inst Physics Acad Sci Czech Republic, 2005) Baleanu, D; Baleanu, Dumitru; Muslih, SI; 56389Fractional Euler-Lagrange equations are investigated in the presence of Grassmann variables. The fractional Hamiltonian and the path integral of the fractional supersymmetric classical model are constructed.Conference Object About metafluid dynamics(inst Physics Acad Sci Czech Republic, 2004) Baleanu, D; Baleanu, Dumitru; 56389The analog of Maxwell electromagnetism for hydrodynamic turbulence, the metafluid dynamics, is investigated as a constrained system within fractional Riemann-Liouville derivatives.Article 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(Elsevier Science Bv, 2005) Dinç, E; Baleanu, Dumitru; Özdemir, A; Baleanu, D; 56389Quantitative 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.Article An approach to quantitative two-component analysis of a mixture containing hydrochlorothiazide and spironolactone in tablets by one-dimensional continuous daubechies and biorthogonal wavelet analysis of UV-spectra(Taylor & Francis inc, 2003) Dinç, E; Baleanu, Dumitru; Baleanu, D; Üstündag, Ö; 56389In this study a new method of quantitative two-component analysis of a mixture of hydrochlorothiazide (HCT) and spironolactone (SP) in the presence of strongly overlapping signals was achieved by using one-dimensional continuous wavelet analysis. This new method was built on the simultaneous use of both continuous wavelet transform and the zero crossing technique for the quantitative resolution of this binary mixture. A series of solutions, in the concentration range of 2-22 mg/ml for both compounds, in methanol and 0.2 M sodium acetate buffer, pH = 5 (20:80), were considered. The absorption spectra of the standard solutions were recorded in the wavelength range of 215-330 nm. To apply our methods we selected 400 points from the absorption spectra and we subjected the corresponding signal to Daubechies2 (DAUB2) and Biorthogonal1.5 (BIOR1.5) one-dimensional wavelet transform. In the transformed signals, the amplitude of HCT was measured at the position of a zero crossing point of SP and vice versa. Thus simple linear regression analysis can be applied to establish calibrations for both components. These calibrations were validated with synthetic mixtures of HCT and SP. MATLAB 6.5 software was used for one-dimensional wavelet analysis, and the basic concepts about wavelet method are briefly explained. The method developed in this paper is rapid, easy to apply, inexpensive and it is suitable for analysis of the overlapping signals of compounds in their mixtures without any chemical pre-treatment.Article Chemometric approach to simultaneous chromatographic determination of paracetamol and chlorzoxazone in tablets and spiked human plasma(Taylor & Francis inc, 2006) Dinç, E; Baleanu, Dumitru; Ozdemir, A; Aksoy, H; Baleanu, D; 6981; 26096New chemometric approaches were introduced into the high performance liquid chromatographic (HPLC) determination of chlorzoxazone (CZX) and paracetamol (PAR) in the tablets and spiked human plasma. These chemometric approaches contain the application of classical least squares (CLS), principle component regression (PCR), and partial least squares (PLS) calibrations to the multiwavelength HPLC peak area obtained by plotting the chromatograms at the five wavelengths. The multichromatograms were obtained by using the photodiode array detector at 225 (A), 240 (B), 255 (C), 270 (D), and 285 (E) nm. The algorithms of CLS, PCR, and PLS were applied to the multichromatogram data to construct the HPLC-CLS, HPLC-PCR, and HPLC-PLS calibrations. A mixture of acetonitrile and 0.1 M ammonium carbonate (60:40, v/v) on a Waters Symmetry (R) trademark C18 Column 5 mu m 4.6 x 250 mm at a flow rate of 0.8 mL/min was used as a mobile phase to separate and determine CZX and PAR in samples. Hydrochlorothiazide (IS) was used as an internal standard in this chromatographic separation. The HPLC chemometric calibrations were successfully applied to the quantitative analysis of the investigated drugs in commercial pharmaceutical preparation and spiked human plasma samples with high precision and accuracy.Article Chemometric Determination of Naproxen Sodium and Pseudoephedrine Hydrochloride in Tablets by HPLC(Pharmaceutical Soc Japan, 2006) Dinç, E; Baleanu, Dumitru; Özdemir, A; Aksoy, H; Üstündag, Ö; Baleanu, D; 6981; 26096; 105547A new chemometric determination by high-performance liquid chromatography (HPLC) with photodiode array (PDA) detection was implemented for the simultaneous determination of naproxen sodium and pseudoephedrine hydrochloride in tablets. Three chemometric calibration techniques, classical least squares (CLS), principle component regression (PCR) and partial least squares (PLS) were applied to the peak area at multiwavelength PDA detector responses. The combinations of HPLC with chernometric calibration techniques were called HPLC-CLS, HPLC-PCR and HPLC-PLS. For comparison purposes the HPLC method called the classic HPLC method was used to confirm the results obtained from combined HPLC-chemometric calibration techniques. A good chromatographic separation between two drugs with losartan potassium as an internal standard was achieved using a Waters Symmetry (R) C18 Column 5 mu m 4.6 +/- 250 mm and a mobile phase containing 0.2 m acetate buffer and acetonitrile (v/v, 40 : 60). The multiwavelength PDA detection was measured at five different wavelengths. The chromatograms were recorded as a training set in the mobile phase. Three HPLC-chemometric calibrations and the classic-HPLC method were used to test the synthetic mixtures of naproxen sodium and pseudoephedrine hydrochloride in the presence of the internal standard. The HPLC-chemometric approaches were applied to real samples containing drugs of interest. The experimental results obtained from HPLC-chemometric calibrations were compared with those obtained by a classic HPLC method.Article Chemometric quantitative analysis of pyridoxine HCl and thiamine HCl in a vitamin combination by principal component analysis, classical least squares, and inverse least squares techniques(Marcel dekker inc, 2001) Dinç, E; Baleanu, Dumitru; Baleanu, D; Onur, F; 56389Three chemometric techniques were described for the analysis of pyridoxine hydrochloride and thiamine hydrochloride within a vitamin combination in the presence of spectral interferences. For these techniques, the training set was prepared by using synthetic mixtures containing two vitamins in multiple possible combinations for the range of 8-40 mu /mL in 0.1 M HCl. The absorbance values for the training set were obtained by direct measurements at 18 wavelengths in the region 222-305 nm for the zero order spectra. The numerical values were calculated by using the 'Maple V' software. Mean recoveries and relative standard deviations for the principal component analysis, classical least squares and inverse least squares techniques were found as 100.7% and 0.95%; 100.5% and 1.38% and, 99.3% and 1.04 for pyridoxine hydrochloride; and 99.7% and 1.03%; 99.1% and 1.05% and, 99.6% and 1.58% for thiamine hydrochloride, respectively. These three chemometric techniques were successfully applied to vitamin tablets marketed in Turkey. The results were compared with each other and good coincidence was observed.Article Comparative study of the continuous wavelet transform, derivative and partial least squares methods applied to the overlapping spectra for the simultaneous quantitative resolution of ascorbic acid and acetylsalicylic acid in effervescent tablets(Elsevier Science Bv, 2005) Dinç, E; Baleanu, Dumitru; Ozdemir, A; Baleanu, D; 56389The simultaneous spectrophotometric determination of ascorbic acid (AA) and acetylsalicylic acid (ASA) in effervescent tablets in the presence of the overlapping spectra was accomplished by the continuous wavelet transform (CWT), derivative spectrophotometry (DS) and partial least squares (PLS) approaches without using any chemical pre-treatment. CWT and DS calibration equations for AA and ASA were obtained by measuring the CWT and DS amplitudes corresponding to zero-crossing points of spectra obtained by plotting continuous wavelet coefficients and first-derivative absorbance values versus the wavelengths, respectively. The PLS calibration was constructed by using the concentration set and its full absorbance data consisting of 850 points from 220 to 305 urn in the range of 210-310 nun. These three methods were tested by analyzing the synthetic mixtures of the above drugs and they were applied to the real samples containing two commercial pharmaceutical preparations of subjected drugs. A comparative study was carried out by using the experimental results obtained from three analytical methodologies and precise and accurate results were obtained. (c) 2004 Published by Elsevier B.V.Article Dual metrics and nongeneric supersymmetries for a class of Siklos space-times(World Scientific Publ Co Pte Ltd, 2002) Baleanu, D; Baleanu, Dumitru; Baskal, S; 56389The presence of Killing-Yano tensors implies the existence of nongeneric supercharges in spinning point particle theories on curved backgrounds. Dual metrics axe defined through their associated nondegenerate Killing tensors of valence two. Siklos space-times, which are the only nontrivial Einstein spares conformal to nonflat pp-waves are investigated with regard to the existence of their corresponding Killing and Killing-Yano, tensors. It is found that a class of Siklos space-times admit dual metrics and nongeneric supercharges.Article Dual metrics for a class of radiative space-times(World Scientific Publ Co Pte Ltd, 2001) Baleanu, D; Baleanu, Dumitru; Baskal, S; 56389Second-rank nondegenerate Killing tensors for some subclasses of space-times admitting parallel null one-planes ace investigated. Lichnerowicz radiation conditions are imposed to provide a physical meaning to space-times whose metrics are described through their associated second-rank Killing tensors. Conditions under which the dual space-times retain the same physical properties are presented.Article Formulation of Hamiltonian equations for fractional variational problems(inst Physics Acad Sci Czech Republic, 2005) Muslih, SI; Baleanu, Dumitru; Baleanu, D; 56389An extension of Riewe's fractional Hamiltonian formulation is presented for fractional constrained systems. The conditions of consistency of the set of constraints with equations of motion are investigated. Three examples of fractional constrained systems are analyzed in details.Article Geometrization of the Lax pair tensors(World Scientific Publ Co Pte Ltd, 2000) Baleanu, D; Baleanu, Dumitru; Baskal, S; 56389The tensorial form of the Lax pair equations are given in a compact and geometrically transparent form in the presence of Cartan's torsion tensor. Three-dimensional space-times admitting Lax tensors are analyzed in detail. Solutions to Lax tensor equations include interesting examples as separable coordinates and the Toda lattice.Article Hamilton-Jacobi and symplectic analysis of a particle constrained on a circle(inst Physics Acad Sci Czech Republic, 2003) Baleanu, Dumitru; Baleanu, D; Güler, Y; Güler, Yurdahan; 56389Hamilton-Jacobi and modified Faddeev-Jackiw methods were applied to investigate the motion of a particle moving on a circle. The results of both methods were found to be equivalent with those of Dirac's formalism. Besides, the importance of the Lagrange multipliers was analyzed and the action of the second-class constrained system was given.Conference Object Hamilton-Jacobi formulation of the Harada gauged Floreanini-Jackiw action(inst Physics Acad Sci Czech Republic, 2002) Baleanu, D; Baleanu, Dumitru; Güler, Y; 56389We study the front-form Harada gauged Floreanini-Jackiw action and its BRST-anti-BRST symmetry within Hamilton-Jacobi formalism.Conference Object Hamilton-Jacobi quantization of constrained systems(inst Physics Acad Sci Czech Republic, 2001) Baleanu, D; Baleanu, Dumitru; Güler, Y; 56389The path integral quantization of contrained systems is analysed using Hamilton-Jacobi formalism. The integrability conditions are investigated and the results are in agreement with those obtained by Dirac's method.Article Hamilton-Jacobi quantization of systems with time-dependent constraints(Kluwer Academic/plenum Publ, 2002) Baleanu, Dumitru; Baleanu, D; Güler, Y; Güler, Yurdahan; 56389Hamilton-Jacobi formalism is used to investigate time-dependent constraint systems. It is proved that the generalization of Dirac's canonical quantization method in the nonstationary case can be obtained naturally in Hamilton-Jacobi formalism. The example of the relativistic particle in a plane wave is analyzed in detail.Article Hamilton-Jacobi treatment of a non-relativistic particle on a curved space(Iop Publishing Ltd, 2001) Baleanu, Dumitru; Baleanu, D; Güler, Y; Güler, Yurdahan; 56389In this paper a non-relativistic particle moving on a hypersurface in a curved space and the multidimensional rotator are investigated using the Hamilton-Jacobi formalism. The equivalence with the Dirac Hamiltonian formalism is demonstrated in both Cartesian and curvilinear coordinates. The energy spectrum of the multidimensional rotator is equal to that of a pure Laplace-Beltrami operator with no additional constant arising from the curvature of the sphere.Article Hamilton-Jacobi treatment of chiral schwinger model(Kluwer Academic/plenum Publ, 2001) Baleanu, D; Baleanu, Dumitru; Güler, Y; 56389We investigate the path integral quantization of the bosonic chiral Schwinger model using multi-Hamilton-Jacobi procedure. The integrability conditions require the extension of the initial phase space. The Wess-Zumino term was recovered calculating the action corresponding to the extended system.