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61.
New chemometric approaches based on the application of partial least squares (PLS) and principal component regression (PCR) algorithms with fractional wavelet transform (FWT) and continuous wavelet transform (CWT) are proposed for the spectrophotometric multicomponent determination of thiamine hydrochloride (B1), pyridoxine hydrochloride (B6), and lidocaine hydrochloride (LID) in ampules without any separation step. In this study PLS and PCR techniques were applied to the raw spectral data, FWT-coefficients, and FWT-CWT-coefficients. These calibration models were labeled as Raw-PLS and Raw-PCR, FWT-PLS and FWT-PCR, and FWT-CWT-PLS and FWT-CWT-PCR, respectively. A new ultra-performance liquid chromatographic (UPLC) method was developed for the comparison of the results obtained by applying the chemometric calibration methods. Chromatographic separation and determination of B1, B6, and LID in ampules were performed on an Acquity UPLC BEH C18 column (50x2.1 mm id, 1.7 pm particle size) using gradient elution with a mobile phase consisting of methanol and 0.01 M HCI at a constant flow rate of 0.6 mL/min. These combined chemometric calibrations and UPLC were validated by analyzing various ternary mixtures, B1, B6, and LID. The proposed chemometric approaches (signal processing-multivariate calibrations) and UPLC method were applied to the quantitative multicomponent analysis of marketed ampules containing the vitamins B1 and B6 with LID. 相似文献
62.
The association constants, Ka of KI, Nal and CaCl2 complexing with 1,4,7,10,13-pentaoxacyclopentadecane and 1,4,7,10,13,16-hexaoxacycloocta-decane in DHO were determined by the aid of 13C dipole-dipole relaxation time measurements. The mole fraction of the complexed ligand, PC were obtained by the use of the equation of 1/Tobs 1 - 1/T10 = PC (1/TO 1 - 1/T10) where the T10 and To 1 are the relaxation times of free and complexed macrocyclic ethers respectively. Ka values obtained from the above given equation depending on the cation concentration, [A+ O] typically reflected the relation between the cationic radius and cyclic ether ring size. 相似文献
63.
Fixed point results are presented for cyclic generalized ${(\phi-\varphi)}$ -contraction mappings on complete metric spaces (X, d). Our results extend previous results given by ?iri?, Moradi and Khojasteh, and Karap?nar. 相似文献
64.
Erdal Karapınar 《Applied Mathematics Letters》2012,25(11):1761-1766
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66.
We have performed two kinds of non-linear fitting procedures to the single-particle energies in the sdgh major shell to obtain better shell model results. The low-lying energy eigenvalues of the light Sn isotopes with A = 103- 110 in the sdgh-shell are calculated in the framework of the nuclear shell model by using CD-Bonn two-body effective nucleonnucleon interaction. The obtained energy eigenvalues are fitted to the corresponding experimental values by using two different non-linear fitting procedures, i.e., downhill simplex method and clonal selection method. The unknown single-particle energies of the states 2s1/2, 1d3/2, and 0h11/2are used in the fitting methods to obtain better spectra of the104,106,108,110 Sn isotopes. We compare the energy spectra of the104,106,108,110 Sn and103,105,107,109 Sn isotopes with/without a nonlinear fit to the experimental results. 相似文献
67.
This study aims at examining how nanotechnology is covered in Turkish print media. As an initial part of this objective, a total of 76 articles derived from a widespread national newspaper were analyzed based on the framing theory. These articles were analyzed using both quantitative and qualitative traditions of content analysis; however, the quantitative method was the primary form of investigation. The analyses showed that the first news about nanotechnology appeared in 1991 and the frequencies of articles had increased in the subsequent years; but the number of articles had decreased after a while. The findings demonstrated a remarkable positive tone in the articles; there were only a few articles in negative tones and these articles were published in the first years of nanotechnology news. It was further found that the articles were mostly concerned with the implementations of nanotechnology, such as research and education centers, medical, and electronics. The study also investigated the presentation style of nanotechnology news. In other words, it investigated how the articles were framed. The results showed that the articles were mostly framed with scientific researches or discoveries and future expectations. 相似文献
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69.
We propose a heuristic procedure that constructs a schedule forN jobs with stochastic processing times and a common due date onM parallel, identical machines. The criterion is the minimization of the total expected incompletion cost. A worst-case analysis for the ratio of the heuristic and optimal solutions is presented and a bound on the ratio is derived. The experimental results presented indicate that the heuristic procedure generates almost optimal solutions. 相似文献
70.
Ercan elik Erdal Karaduman Mustafa Bayram 《International journal of quantum chemistry》2002,89(5):447-451
In this article, the solution of a chemical differential‐algebraic equation model of general type F(y, y′, x) = 0 has been done using MAPLE computer algebra systems. The MAPLE program is given in the Appendix . First we calculate the Power series of the given equations system, then we transform it into Padé series form, which gives an arbitrary order for solving chemical differential‐algebraic equation numerically. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002 相似文献