Browsing by Author "Dinç, Erdal"

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Citation Count: Dinç, E...et al. (2012). A new approach to the characterization of the nano-surface structure by using factor analysis. Communications In Nonlinear Science And Numerical Simulation, 17(2), 1012-1020. http://dx.doi.org/10.1016/j.cnsns.2011.02.029
A new approach to the characterization of the nano-surface structure by using factor analysis
(Elsevier Science Bv, 2012) Dinç, Erdal; Baleanu, Dumitru; Solak, Ali Osman; Ekşi, Haslet; Güzel, Remziye; 6981; 234363; 192756
The study provides a new approach to explore the existence of a nanostructure on the benzoic acid-modified glassy carbon electrode (BA-GC) system by applying factor analysis with varimax rotation of factors. The infrared spectra (IR) spectra of the bare glassy carbon electrodes (GC) and the BA-GC electrode systems with benzoic acid-nanofilm (BA-FILM) were obtained by using 10 different surface modification experiments. The IR data of the bare GC, BA-GC and BA-FILM were categorized into three series corresponding to the GC, BA-GC and BA-FILM. The factor analysis method was separately applied to each group to extract the factor loadings. By making use of these loadings, the rotated factor loadings corresponding to the first two factors were computed to estimate the relationship among and within groups. The results provided by the factor analysis method indicate the existence of the BA-FILM on the BA modified glassy carbon electrode
Citation Count: Dinç, E., Baleanu, D., (2006). A new fractional wavelet approach for the simultaneous determination of ampicillin sodium and sulbactam sodium in a binary mixture. Spectrochimica Acta Part A-Molecular And Biomoleculer Spectroscopy, 63(3), 631-638. http://dx.doi.org/10.1016/j.saa.2005.06.012
A new fractional wavelet approach for the simultaneous determination of ampicillin sodium and sulbactam sodium in a binary mixture
(Pergamon-Elsevier Science, 2006) Dinç, Erdal; Baleanu, Dumitru; 6981
A new application of the fractional wavelet transform (FWT) was proposed for the simultaneous determination of ampicillin (AP) and sulbactam (SB) in a pharmaceutical combination for injection. FWT approach is a new powerful tool for removing noise and irrelevant information from the absorption spectra. Cardinal information having higher peak amplitude, eliminated noise, sharp peaks with shrinking width of spectral range was obtained by the application of FWT procedure to the original absorption spectra. In this paper, FWT approach was subjected to the data vector of the UV-signals obtained from AP and SB in the wavelength range of 211.5-313.8 nm. Derivative transform was applied to the original absorption signal together with its FWT generalization. The calibration graphs for AP and SB were obtained by measuring the FWT and usual derivative amplitudes at zero-crossing points. The method validation was carried out by using the synthetic mixture analysis. Our proposed FWT approach was compared with the usual derivative spectrophotometry and chemometric methods (CLS, PCR and PLS) and a good agreement was reported. (c) 2005 Elsevier B.V. All rights reserved
Citation Count: Dinç, E.; Kas, F.; Baleanu, D., "A Signal Processing Tool Based On the Continuous Wavelet for the Simultaneous Determination of Estradiol Valerate and Cyproterone Acetate in Their Mixtures", Revista de Chimie, Vol. 64, No. 2, pp. 124-126, (2013).
A Signal Processing Tool Based On the Continuous Wavelet for the Simultaneous Determination of Estradiol Valerate and Cyproterone Acetate in Their Mixtures
(SYSCOM 18 S.R.L., 2013) Dinç, Erdal; Kaş, Fatih; Baleanu, Dumitru; 56389
A signal processing tool based on the continuous wavelet transform (CWT) was proposed for the simultaneous determination of estradiol valerate (EV) and cyproterone acetate (CA) in their mixtures. Different continuous wavelet families were tested in order to rind the optimum family of the wavelets. The Symlets 8 continuous wavelet transform (SYM8-CWT) was obsewed to be the optimal one. The SYM8-CWT approach was applied to the absorption spectra of the related compounds in the spectral range of 210.00-312.35 nm for the calibration solutions of the compounds in the concentration range of 10-50 μg/ml for EV and 5-30 μg/mL for CA. The calibration equations for EA and CA were computed by measuring the continuous wavelet signals at 260.75 nm and 238.40 nm, respectively. The proposed method was validated by the independent analysis of the synthetic mixtures and by the standard addition technique. It was observed that the selectivity and the sensitivity in the application of the db5-CWT method to the determination of EV and CA compounds were satisfactory.
Citation Count: Dinç, E.; Baleanu, Dumitru, "A zero-crossing technique for the multidetermination of thiamine HCl and pyridoxine HCl in their mixture by using one-dimensional wavelet transform" Journal Of Pharmaceutical And Biomedical Analysis
A zero-crossing technique for the multidetermination of thiamine HCl and pyridoxine HCl in their mixture by using one-dimensional wavelet transform
(Pergamon-Elsevier Science LTD, 2003) Dinç, Erdal; Baleanu, Dumitru; 56389
A 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.
Citation Count: Dinç, e., Arslan, F., Baleanu, D. (2009). Alternative approaches to the spectral quantitative resolution of two-component mixture by wavelet families. Journal of the Chilean Chemical Society, 54(1), 28-35.
Alternative approaches to the spectral quantitative resolution of two-component mixture by wavelet families
(Soc Chilena Quimica, 2009) Dinç, Erdal; Arslan, Fahrettin; Baleanu, Dumitru; 6981
A new spectral continuous wavelet transform (CWT) methods are proposed for the quantitative analysis of the binary mixtures. The simultaneous spectral resolution of binary mixtures and tablets containing paracetamol (PAR) and chloroxozone (CHL) with overlapping absorption spectra is performed by six wavelet families with no chemical separation procedure. The calibration graphs for the six wavelet families are obtained by the help of the data collected from the CWT-signal amplitudes corresponding to the zero crossing points in the spectral range of 210 nm-310 nm. The validation of each wavelet family is carried out by analyzing various synthetic binary mixtures of the above mentioned drugs. The second derivative spectrophotometry (D2) is used to compare the experimental results provided by the analyzed continuous wavelet families and a good coincidence is reported for the proposed analytical approaches
Citation Count: Dinç, E.; Özdemir, A.; Baleanu, D., "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", talanta, Vol.65, No.1, pp.36-47, (2005).
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, Erdal; Özdemir, Abdil; Baleanu, Dumitru; 56389
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.
Citation Count: Dinç, E., Şen Köktaş, N., Baleanu, D. (2009). An Application of Principal Component Analysis - Artificial Neural Network for the Simultaneous Quantitative Analysis of a Binary Mixture System. Revista De Chimie, 60(7), 662-665.
An Application of Principal Component Analysis - Artificial Neural Network for the Simultaneous Quantitative Analysis of a Binary Mixture System
(Chiminform Data S A, 2009) Dinç, Erdal; Şen Köktaş, Nigar; Baleanu, Dumitru; 6981
Artificial 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
Citation Count: Baleanu, Dumitru; Dinç, E.; Ustundağ, O., "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" Spectroscopy Letters, Vol.36, No.4, pp.341-355, (2003).
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, Erdal; Baleanu, Dumitru; Üstündağ, Özgür; 56389
In 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.
Citation Count: Nigmatullin, R.R...et al. (2010). Analysis of a nanofilm of the mercaptophenyl diazonium modified gold electrode within new statistical parameters. Journal of Computational and Theoretical Nanoscience, 7(3), 562-570. http://dx.doi.org/10.1166/jctn.2010.1395
Analysis of a nanofilm of the mercaptophenyl diazonium modified gold electrode within new statistical parameters
(Amer Scientific Publishers, 2010) Nigmatullin, Raoul R.; Baleanu, Dumitru; Dinç, Erdal; Üstündağ, Zafer; Solak, Ali Osman; Kargin, Roman V.; 6981; 129297
The main aim of this study is to characterize the nanosurface of the mercaptophenyl diazonium modified gold (Au) surface by a new statistical approach. In this study the gold electrode surfaces were self-assembled in ethyl alcohol by 1.0 mM mercaptophenyl diazonium. FT-IR spectra of the surface modifier molecules in both solid and nanofilm of mercaptophenyl diazonium (MCP-Au) forms were recorded in the spectral range of 600-4,000 cm(-1). The FT-IR spectra of solid mercaptophenyl diazonium tetrafluoroborate salt were obtained by using KBr pellets. The above FT-IR spectra of both bare Au and its nanofilm of mercaptophenyl diazonium were processed by new statistical approach to reach optimal smoothing trend for the characterization of the modified electrode surface consisting of the nanofilm of gold-mercaptophenyl diazonium. In the frame of new statistical approach all measured spectra have been 'read' in terms of a set of universal statistical parameters. These new parameters help to establish the statistical proximity of the smoothed spectra compared and give a possibility to classify the measured spectra in accordance with new set of statistical and robust quantitative values. Besides, there is a possibility to receive the relative fluctuations and the smoothed spectra of the second order. So, thanks to new approach we do not loose any measured information: the smoothed spectra and accompanied them noise (relative fluctuations) can be analyzed separately for detection of possible influence of predominant external factors that can be essential for this type of measurements
Citation Count: Nigmatulin, R.R...et al. (2010). Analysis of the effect of potential cycles on the reflective infrared signals of nitro groups in nanofilms: application of the fractional moments statistics. Electroanalysis, 22(4), 419-426. http://dx.doi.org/10.1002/elan.200900369
Analysis of the effect of potential cycles on the reflective infrared signals of nitro groups in nanofilms: application of the fractional moments statistics
(Wiley, 2010) Nigmatullin, Raoul R.; Alekhin, A. P.; Baleanu, Dumitru; Dinç, Erdal; Üstündağ, Zafer; Ekşi, Haslet; Solak, Ali Osman; 6981
The effect of the potential cycles on the reflective IR signals of nitro-groups in nanofilms was studied for the statistical characterization of nitrobenzene (NB) and nitroazobenzene (NAB)-modified glassy carbon (GC) surfaces. Both NB and NAB nanofilms were obtained by the electrochemical reduction of the diazonium tetrafluoroborate salts in acetonitrile using cyclic voltammetry (CV). The modified surfaces were denoted as GC-(NB)(n) and GC-(NAB)(n), respectively, where n indicates the number of CV cycles performed during modification. Reflective IR signals of the normalized NB and NAB nanofilms and GC were used for the quantitative evaluation of the effect of the potential cycles on the reflective IR signals of nitro-groups in nanofilms. The detection and quantitative 'reading' of the influence of number of CV cycles were realized in the frame of a new error controllable approach that was applied for analysis of all available set of data. This approach includes in itself the following basic steps: (a) the procedure of the division (normalization) on the GC spectra, (b) the comparison of the smoothed spectra for their statistical proximity in the frame of the statistics of the fractional moments, (c) extraction of possible calibration parameters for possible calibration of the normalized spectra with respect to the number of CV cycles. These three basic steps are becoming effective for detection of the influence of some external factors. In our case it is important to detect the influence of the factor n characterizing CV cycles
Citation Count: Machado, J.A.T., Dinç, E., Baleanu, D. (2015). Analysis of UV spectral bands using multidimensional scaling. Signal Image And Video Processing, 9(3), 573-580. http://dx.doi.org/10.1007/s11760-013-0485-7
Analysis of UV spectral bands using multidimensional scaling
(Springer London LTD, 2015) Machado, J. A. Tenreiro; Dinç, Erdal; Baleanu, Dumitru; 6981
This study describes the change of the ultraviolet spectral bands starting from 0.1 to 5.0 nm slit width in the spectral range of 200-400 nm. The analysis of the spectral bands is carried out by using the multidimensional scaling (MDS) approach to reach the latent spectral background. This approach indicates that 0.1 nm slit width gives higher-order noise together with better spectral details. Thus, 5.0 nm slit width possesses the higher peak amplitude and lower-order noise together with poor spectral details. In the above-mentioned conditions, the main problem is to find the relationship between the spectral band properties and the slit width. For this aim, the MDS tool is to used recognize the hidden information of the ultraviolet spectra of sildenafil citrate by using a Shimadzu UV-VIS 2550, which is in the world the best double monochromator instrument. In this study, the proposed mathematical approach gives the rich findings for the efficient use of the spectrophotometer in the qualitative and quantitative studies.
Citation Count: Dinç, E...et al. (2015). Application of continuous wavelet transform to the analysis of the modulus of the fractional Fourier transform bands for resolving two component mixture. Signal Image And Video Processing, 9(4), 801-807. http://dx.doi.org/10.1007/s11760-013-0503-9
Application of continuous wavelet transform to the analysis of the modulus of the fractional Fourier transform bands for resolving two component mixture
(Springer London LTD, 2015) Dinç, Erdal; Duarte, Fernando B.; Machado, J. A. Tenreiro; Baleanu, Dumitru; 6981
In this paper, the fractional Fourier transform (FrFT) is applied to the spectral bands of two component mixture containing oxfendazole and oxyclozanide to provide the multicomponent quantitative prediction of the related substances. With this aim in mind, the modulus of FrFT spectral bands are processed by the continuous Mexican Hat family of wavelets, being denoted by MEXH-CWT-MOFrFT. Four modulus sets are obtained for the parameter of the FrFT going from 0.6 up to 0.9 in order to compare their effects upon the spectral and quantitative resolutions. Four linear regression plots for each substance were obtained by measuring the MEXH-CWT-MOFrFT amplitudes in the application of the MEXH family to the modulus of the FrFT. This new combined powerful tool is validated by analyzing the artificial samples of the related drugs, and it is applied to the quality control of the commercial veterinary samples.
Citation Count: Dinç, E., Baleanu, D. (2008). Application of Haar and Mexican hat wavelets to double divisor-ratio spectra for the multicomponent determination of ascorbic acid, acetylsalicylic acid and paracetamol in effervescent tablets. Journal of the Brazilian Chemical Society, 19(3), 434-444. http://dx.doi.org/10.1590/S0103-50532008000300010
Application of Haar and Mexican hat wavelets to double divisor-ratio spectra for the multicomponent determination of ascorbic acid, acetylsalicylic acid and paracetamol in effervescent tablets
(Soc Brasileira Quimica, 2008) Dinç, Erdal; Baleanu, Dumitru; 6981
Simultaneous determination of ascorbic acid (AA), acetylsalicylic acid (ASP) and paracetamol (PAR) in their synthetic mixtures and effervescent tablets were performed by Haar and Mexican continuous wavelet transforms (HAAR-CWT and MEXH-CWT, respectively) together with double divisor technique. The signal processing methods are based on the application of HAAR-CWT and MEXH-CWT to the double divisor-ratio spectra (DDRS). These spectra were obtained by dividing the absorption spectra of pure compound and its ternary mixtures by a double-divisor or standard spectrum corresponding to a mixture of two compounds in ternary mixture. A combined use of HAAR-CWT and MEXH-CWT with double divisor-ratio spectra (DDRS) was denoted by DDRS-HAAR CWT and DDRS-MEXH CWT. To check the ability or applicability of the developed DDRS-CWT methods, the double divisor-ratio spectra-derivative spectrophotometric (DDRS-DS) method, as a comparison method, was applied to the above mentioned samples containing AA, ASP and PAR and satisfactory results were obtained
Citation Count: Nigmatullin, R.R...et al. (2011). Application of the linear principle for the strongly-correlated variables: Calculations of differences between spectra. Communications In Nonlinear Science And Numerical Simulation, 16(10), 4028-4036. http://dx.doi.org/10.1016/j.cnsns.2011.02.005
Application of the linear principle for the strongly-correlated variables: Calculations of differences between spectra
(Elsevier Science, 2011) Nigmatullin, Raoul R.; Popov, I. I.; Baleanu, Dumitru; Dinç, Erdal; Solak, A. U.; Ekşi, H.; Güzel, R.; 6981
In this paper the authors suggest a new method of detection of possible differences between similar near infrared (NIR) spectra based on the self-similar (fractal) property. This property is a general characteristic that belongs to a wide class of the strongly-correlated systems. As an example we take a set of NIR spectra measured for three systems: (1) glassy carbon (GC) electrodes, (2) GC electrodes affected by azobenzene (AB) substance and finally (3) films (AB-FILM). Besides the physical model that should describe the intrinsic properties of these substances we found the fitting function that follow from the linear principle for the strongly-correlated variables. This function expressed in the form of linear combination of 4 power-law functions describes with the high accuracy the integrated curves that were obtained from the averaged values of the initially measured spectra. The nine fitting parameters can be considered as the quantitative "finger prints" for detection of the differences between similar spectra. Besides this result we established the self-similar behavior of the remnant functions. In other words, the difference between the initially integrated function and its fitting function can be expressed in the form of linear combinations of periodical functions having a set of frequencies following to relationship omega(k) = omega(0)xi(k), where the initial frequency omega(0) and scaling factor xi are determined by the eigen-coordinates method. This behavior in the NIR spectra was discovered in the first time and physical reasons of such behavior merit an additional research
Citation Count: Dinç, E.; Baleanu, Dumitru, "Application of the wavelet method for the simultaneous quantitative determination of benazepril and hydrochlorothiazide in their mixtures" Journal of AOAC International, Vol.87, No.4, pp.834-841, (2004).
Application of the wavelet method for the simultaneous quantitative determination of benazepril and hydrochlorothiazide in their mixtures
(AOAC International, 2004) Dinç, Erdal; Baleanu, Dumitru; 56389
The discrete and continuous wavelet transforms were applied to the overlapping signal analysis of the ratio data signal for simultaneous quantitative determination of the title subject compounds in samples. The ratio spectra data of the binary mixtures containing benazepril (BE) and hydrochlorothiazide (HCT) were transferred as data vectors into the wavelet domain. Signal compression, followed by a 1-dimension continuous wavelet transform (CWT), was used to obtain coincident transformed signals for pure BE and HCT and their mixtures. The coincident transformed amplitudes corresponding to both maximum and minimum points allowed construction of calibration graphs for each compound in the binary mixture. The validity of CWT calibrations was tested by analyzing synthetic mixtures of the investigated compounds, and successful results were obtained. All calculations were performed within EXCEL, C++, and MATLAB6.5 softwares. The obtained results indicated that our approach was flexible and applicable for the binary mixture analysis.
Citation Count: Üstündağ, Ö., Dinç, E., Baleanu, D. (2008). Applications of Mexican Hat Wavelet Function to Binary Mixture Analysis. Revista De Chimie, 59(12), 1387-1391.
Applications of Mexican Hat Wavelet Function to Binary Mixture Analysis
(Chiminform Data S A, 2008) Üstündağ, Özgür; Dinç, Erdal; Baleanu, Dumitru; 105547; 6981
The simultaneous determination of pyridoxine hydrochloride (B6) and isoniazide (INH) in tablets was performed by using the Mexican hat wavelet function (MEXH). The absorption spectra of B6, INH and their samples were recorded in the spectral range of 200-330 nm. Linear regression functions for B6 and INH in the linear concentration range of 5-45 mu g/mL were obtained by measuring the transformed signals at 253.5 nm corresponding to the zero-crossing point for INH and at 270.6 nm corresponding to the zero-points for B6, respectively. The validation of MEXH method was performed by using the synthetic mixtures. The percent mean recoveries and their relative standard deviations were found as 98.7% and 2.06 for B6 and 98.9% and 1.89 for INH in the synthetic mixture analysis. The MEXH method was applied to the real samples and a good sensitivity and selectivity was reported. The MEXH method was sucessfully compared with classical derivative method
Citation Count: Tenreiro Machado, J.A...et al. (2011). Characterization approach to modified glassy carbon electrode-nanofilm system within multidimensional scaling. Journal of Computational and Theoretical Nanoscience, 8(2), 268-273. http://dx.doi.org/10.1166/jctn.2011.1688
Characterization approach to modified glassy carbon electrode-nanofilm system within multidimensional scaling
(Amer Scientific Publishers, 2011) Tenreiro Machado, J. A.; Baleanu, Dumitru; Dinç, Erdal; Solak, Ali Osman; Ekşi, Haslet; Güzel, Remziye; 6981; 192756
The aim of this work is to characterize the nanofilm consisting of the benzoic acid-modified glassy carbon (GC) electrode system through multidimensional scaling space analysis. The surface modification is based on the electrochemical reaction between the GC electrode and benzoic acid-diazonium salt (BA-DAS). As a result, the nonofilms regarding the benzoic acid-glassy carbon (BA-GC) electrode surface was obtained. For the analysis of the naonfilm of BC-GC electrode system, the IR spectra of the modified BA-GC electrode surface, GC surface and BA-DAS were recorded in the spectral range of 599.84 - 3996.34 [cm(-1)]. The IR data vectors of the above three forms were processed by the using the multidimensional scaling space approach to demonstrate the existence of a nanofilm on the modified BA-GC electrode system. Two- and three-dimensional MDS profiles obtained by application of multidimensional scaling approach to the data sets {CG1, ... ,CG10}, {BA-GC1, ... ,BA-GC10} and {FILM1, ... ,FILM10} allow a good recognition of the nanofilm on the modified glassy carbon (GC) electrode system
Citation Count: Nigmatullin, R.R...et al. (2009). Characterization of a benzoic acid modified glassy carbon electrode expressed quantitatively by new statistical parameters. Physica-Low-Dimensional Systems&Nanostructures, 41(4), 609-616. http://dx.doi.org/10.1016/j.physe.2008.10.015
Characterization of a benzoic acid modified glassy carbon electrode expressed quantitatively by new statistical parameters
(Elsevier Science Bv, 2009) Nigmatullin, Raoul R.; Baleanu, Dumitru; Dinç, Erdal; Solak, Ali Osman; 6981
The main aim of this study is to characterize the nanosurface of the benzoic acid modified glassy carbon (GC) electrode by using a new statistical approach. In this study, the electrode surfaces were modified by cyclic voltametry in the potential range of +0.4 and -0.8 V at a scan rate 200 mV s(-1) for four cycles versus Ag/Ag(+) electrode in acetonitrile containing 0.1 M tetrabutylammonium tetraflouroborate (TBATFB). FT-IR spectra of the surface modifier molecules in both solid (GC and nanofilm (GC-benzoic acid)) forms were recorded in the spectral range 600-4000 cm(-1). The FT-IR spectra of p-aminobenzoic acid were obtained by using KBr pellets. The above FT-IR spectra of both GC and its nanofilm with benzoic acid were processed by new statistical approach to reach optimal smoothing trend for the characterization of the modified electrode surface consisting of the nanofilm of GC-benzoic acid. In the frame of new statistical approach all measured spectra have been 'read' in terms of a set of universal statistical parameters
Citation Count: Dinç, E...et al. (2006). Chemometric approach to simultaneous chromatographic determination of paracetamol and chlorzoxazone in tablets and spiked human plasma. Journal of Liquid Chromatography & Related Technologies, 29(12), 1803-1822. http://dx.doi.org/10.1080/10826070600717023
Chemometric approach to simultaneous chromatographic determination of paracetamol and chlorzoxazone in tablets and spiked human plasma
(Taylor&Francis Inc, 2006) Dinç, Erdal; Özdemir, Abdil; Aksoy, Halil; Baleanu, Dumitru; 6981; 26096
New 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
Citation Count: Dinç,E.; Baleanu, D.; Üstündağ, O.; Taş, K., "Chemometric calibration based on the wavelet transform for the quantitative resolution of two-colorant mixtures", Revue Roumaine De Chime, Vol.50, No.4, pp.283-290, (2005).
Chemometric calibration based on the wavelet transform for the quantitative resolution of two-colorant mixtures
(Editura Academiei Romane, 2005) Dinç, Erdal; Baleanu, Dumitru; Üstündağ, O.; Taş, Kenan; 56389; 4971
In 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.