The main object of this paper is the approximate Bayes estimation of the five dimensional vector of parameters and the reliability function of a mixture of two Weibull distributions under Type-2 censoring. Under Type-2 censoring, the posterior distribution is complicated, and the integrals involved cannot be obtained in a simple closed form. In this work, Lindley's (1980) approximate form of Bayes estimation is used in the case of a mixture of two Weibull distributions under Type-2 censoring. Through Monte Carlo simulation, the root mean squared errors (RMSE's) of the Bayes estimates are computed and compared with the corresponding estimated RMSE's of the maximum likelihood estimates.

The main object of this paper is the approximate Bayes estimation of the five dimensional vector of parameters and the reliability function of a mixture of two Weibull distributions under Type-2 censoring. Under Type-2 censoring, the posterior distribution is complicated, and the integrals involved cannot be obtained in a simple closed form. In this work, Lindley's (1980) approximate form of Bayes estimation is used in the case of a mixture of two Weibull distributions under Type-2 censoring. Through Monte Carlo simulation, the root mean squared errors (RMSE's) of the Bayes estimates are computed and compared with the corresponding estimated RMSE's of the maximum likelihood estimates.

Errors of misclassification and their probabilities are studied for classification problems associated with two classes of univariate gamma distribution. The effects of applying the normal classificatory rule to gamma populations are also studied and assessed by comparing probabilities (optimum and conditional) based on the linear discriminant function (LDF) for normality with those based on the likelihood ratio rule (LR) for gamma populations. To determine the form in the onev-ariable case, formulas for the exact distribution and density functions of the actual error rates are presented. Both theoretical and empirical results are considered.

A procedure is presented for finding maximum likelihood estimates of the parameters of a mixture of two gamma distributions; those results are given for classified and unclassified observations. The performance of the estimates based on small samples is studied by simulation experiments. Estimation of the discriminant function on the basis of a small sample size is considered. Its performance is investigated by a series of simulation experiments.

The incorporation of 9,10-anthraquinone-1,5-disulfonate (AQS2) into the protonated form of poly(o-toluidine) (POT), produced by oxidative polymerization of the cationic form of the monomer or by doping the basic form (POT-EB) by anion-exchange has been studied by FTIR and UV-VIS spectroscopy and mass spectrometry. The presence of sulfur and the absence of chlorine proven by elemental analysis of the polymer product confirmed the substitution of the chloride anion with AQS2 in the matrix. Molecular mechanics (MM+) calculations suggest that the optimal geometric structure (OMG) of AQS2-doped POT is at least three (3.92) times more stable than that of the parent chloride-doped POT (HCl-doped POT). The increase of the absorbance at about 840 nm associated with the increasing concentration of AQS2 revealed the insertion of AQS2 into the POT chain. This observation could be explained by the diffusion of AQS2 in the polymer chain. Kinetic parameters of the oxidative polymerization of the cationic form of o-toluidine (o-T-HClO4) in the presence of different amounts of AQS2 were deduced on the basis of absorbance variations. The results of computer-oriented kinetic analysis indicate that the rate-controlling step of the o-T polymerization is governed by the Ginstling—Bronstein equation representing the three-dimensional diffusion (D4). Activation parameters of the oxidative polymerization of protonated o-T in the presence of varying amount of AQS2 were computed and discussed.

Ox i da tive poly mer iza tion re ac tion of 8-hydroxyquinoline (HQ) in dif fer ent me dia has been stud ied ex per i men tally by spec tro pho to met ric tech nique and con firmed computationally by mo lec u lar me chan ics (MM+) cal cu la tions. MM+ cal cu la tions showed that the PE of the op ti mum mo lec u lar geo met ric (OMG) of the an ionic HQ (HQ-NaOH) form is about two (1.985) times greater than the PE in the protonated (HQ-HCl) form. PE of the OMG struc ture of the PHQ was com puted (–30.651 kJ mol–1). These cal cu la tions in di cate that the ma trix is highly sta ble. The ox i da tion con stant (Kox) of the an ionic form (HQ-NaOH) is about twice (2.02) greater than that of the protonated (HQ-H2SO4) form. The pro posed pro ce dure was suc cess fully ap plied for the ox i da tion of diiodohydroxyquinoline in streptoquin (SQ) (anti-di ar rhea, tab lets). The Kox of HQ in SQ was also found to be lower than the Kox in syn thetic (HQ) so lu tion. Ki netic pa ram e ters of the ox i da tive poly mer iza tion of the an ionic form of HQ (HQ-NaOH) were de duced on the ba sis of absorbance vari a tions. The re sults of com puter-ori ented ki netic anal y sis in di - cate that the rate-con trol ling step of the HQ poly mer iza tion is gov erned by Ginstling-Bronstein equa tion rep re sent ing the three-di men sional dif fu sion (D4). Ac ti va - tion pa ram e ters of the ox i da tive poly mer iza tion of the an ionic form of HQ (HQ-NaOH) were com puted and dis cussed.

Ox i da tive poly mer iza tion re ac tion of 8-hydroxyquinoline (HQ) in dif fer ent me dia has been stud ied ex per i men tally by spec tro pho to met ric tech nique and con firmed computationally by mo lec u lar me chan ics (MM+) cal cu la tions. MM+ cal cu la tions showed that the PE of the op ti mum mo lec u lar geo met ric (OMG) of the an ionic HQ (HQ-NaOH) form is about two (1.985) times greater than the PE in the protonated (HQ-HCl) form. PE of the OMG struc ture of the PHQ was com puted (–30.651 kJ mol–1). These cal cu la tions in di cate that the ma trix is highly sta ble. The ox i da tion con stant (Kox) of the an ionic form (HQ-NaOH) is about twice (2.02) greater than that of the protonated (HQ-H2SO4) form. The pro posed pro ce dure was suc cess fully ap plied for the ox i da tion of diiodohydroxyquinoline in streptoquin (SQ) (anti-di ar rhea, tab lets). The Kox of HQ in SQ was also found to be lower than the Kox in syn thetic (HQ) so lu tion. Ki netic pa ram e ters of the ox i da tive poly mer iza tion of the an ionic form of HQ (HQ-NaOH) were de duced on the ba sis of absorbance vari a tions. The re sults of com puter-ori ented ki netic anal y sis in di - cate that the rate-con trol ling step of the HQ poly mer iza tion is gov erned by Ginstling-Bronstein equa tion rep re sent ing the three-di men sional dif fu sion (D4). Ac ti va - tion pa ram e ters of the ox i da tive poly mer iza tion of the an ionic form of HQ (HQ-NaOH) were com puted and dis cussed.

The electronic energies among different possible structures of 4-hydroxyacetanilide (paracetamol) (PA) molecule, were calculated using INDO method and it has been concluded that its structure has Cs point group symmetry of the cis-form. The ionization potential, electron affinity, dipole moment and binding energy have been calculated. The calculated electronic transitions of the cis-form of PA using SCF-CI method have good coincidence with the electronic absorption spectrum. The temperature effect on the electronic spectrum of PA confirms the presence of one conformer only. The electronic spectra of PA compound were studied in different polar- and non-polar solvents and the hydrogen bonding as well as the orientation energies of the polar solvents were determined from the mixed solvents studies. Complexes of PA with various metal ions such as, Cu(II), Zn(II) or Fe(II) ions of ratio 2:1, respectively, have been prepared and their structure has been confirmed by elemental analysis, atomic absorption spectra, IR spectra and 1H NMR spectra and finally it can be concluded that the structure of the complexes has C2h point group symmetry in which two PA molecules are chelated to any one of the metal ions, Cu(II), Zn(II) and Fe(II) ions.

The electronic energies among different possible structures of 4-hydroxyacetanilide (paracetamol) (PA) molecule, were calculated using INDO method and it has been concluded that its structure has Cs point group symmetry of the cis-form. The ionization potential, electron affinity, dipole moment and binding energy have been calculated. The calculated electronic transitions of the cis-form of PA using SCF-CI method have good coincidence with the electronic absorption spectrum. The temperature effect on the electronic spectrum of PA confirms the presence of one conformer only. The electronic spectra of PA compound were studied in different polar- and non-polar solvents and the hydrogen bonding as well as the orientation energies of the polar solvents were determined from the mixed solvents studies. Complexes of PA with various metal ions such as, Cu(II), Zn(II) or Fe(II) ions of ratio 2:1, respectively, have been prepared and their structure has been confirmed by elemental analysis, atomic absorption spectra, IR spectra and 1H NMR spectra and finally it can be concluded that the structure of the complexes has C2h point group symmetry in which two PA molecules are chelated to any one of the metal ions, Cu(II), Zn(II) and Fe(II) ions.

Poly (o-toluidine) (POT) doped with salicylidene-o-aminophenol (SAP) was prepared and characterized using several spectroscopic techniques. The potential (PE) and optimum molecular geometric (OMG) energies and dipole moment (μ) in kcal/mol and debbye units of the different structures of the dopant (SAP) were calculated using molecular mechanics (MM) calculations. MM calculations suggest that the optimum geometric structure (OMG) of SAP-doped POT is at least three orders of magnitude (3.69 x 103) more stable than of that of the molecular geometric structure of the same matrix. 1HNMR spectra and MM calculations described that the –OH group in the dopant (SAP) is almost free. Decrease of the absorbance at ~600 nm due to the quinoid structure of the base form of POT (POT-EB) after addition of SAP at constant concentration of POT reveals that the POT-EB was reduced to a lower oxidation state by SAP during the formation of the SAP-doped POT matrix. The detection limit for dopant (SAP) is as low as 10.66 ppm (mg/L). Transparent composite of spectroactive particles (SAP-doped POT) with the following conventional host polymers, poly (acrylic acid) (PAA), poly (methyl metha acrylate) (PMMA), poly (vinyl alcohol) (PVA), poly (ethylene glycol) (PEG), and poly (vinylpyrrolidone) (PVP) were fabricated. This transparent coating composite can be useful in certain applications such as antistatic coating in electronic industry where a visual inspection is necessary.