A new hetrocyclic liquid crystal compounds containing 1,3,4-oxadiazole with different substituted in para position (Bromo, Chloro, Nitro and Methyl) were synthesized and characterized by melting points, FTIR Spectroscopy and 1HNMR spectroscopy for [Cl-SR6] and [NO2-SR6] compounds. The liquid crystalline properties of the synthesized compounds were studied by using hot-stage polarizing optical microscopy (POM), so they determined the transition enthalpies and entropies by using differential scanning calorimetery (DSC). All of the compounds show mesomorphic properties. The compounds [Br-SR6], [Cl-SR6] and [NO2SR6] exhibit an enantiotropic dimorphism smectic (Sm) phase, while the compounds [MeSR6] showed nematic (N) phase thro

In this paper, some estimators for the reliability function R(t) of Basic Gompertz (BG) distribution have been obtained, such as Maximum likelihood estimator, and Bayesian estimators under General Entropy loss function by assuming non-informative prior by using Jefferys prior and informative prior represented by Gamma and inverted Levy priors. Monte-Carlo simulation is conducted to compare the performance of all estimates of the R(t), based on integrated mean squared.

Abstract Background: This in-vitro study was to evaluated bitewing radiograph and tactile examination for detection secondary caries adjacent to amalgam restorations. Material and method: Sixty primary extracted molars with class I and class II amalgam restorations were selected from children, and examined by bitewing radiographs were taken by using film holders and interpreted on a backlit screen without magnification. Then, we used tactile examination with blunt probe. Result: The result of this study showed that the best cut-off points for the sample were found by a Receiver Operator Characteristic (ROC) analysis, and the area under the ROC curve and the sensitivity, specificity and accuracy of the techniques were calculated for enamel (

The objective of this study was to investigate the release profile of different fat and water soluble bases using diazepam as a model drug , and then to develop  a satisfactory formula with a rapid release of diazepam from suppository bases .The study was conducted using theobroma oil ,glycerol-gelatin and glycerol-PEG1540 bases using conventional mold method for preparation .while the later base was utilized to incorporate diazepam ( buffered solution ) in a hollow type suppositories. The results indicated that all types of bases can be utilized to formulate diazepam as  rectal suppositories with acceptable disintegration time ( 12, 10, 6, and 6min.), respectively . While 100% of the  released drug had been shown differen

The relation between the output power and wavelengths for a 532nm 3W frequency doubled diode pumped solid state laser pumped Ti:Sapphire crystal is investigated. A 20 femtosecond pulse at 800 nm is obtained. A 320 mW is found to be the highest power at 800nm. Below this wavelength value and above the power was found to deviate from highest output value.

         The study included evaluation of cell surface charge and hydrophobicity of Escherichia coli, Klebsilla aerogenes, Proteus spp, Bacillus cereus, Staphylococcus epidermidis, Staphylococcus aureus(1) and Staphylococcus aureus(2) were determined by hydrocarbon adherence and hydrophobic interaction chromatography. The results showed that the negative charge of cell surface of gram negative bacteria was much higher than on gram positive once when these bacteria were grown on nutrient agar at 37 c for 18 h . E.coli was more negative charged than Klebsilla aerogenes and Proteus spp. The hydrophobicity of gram positive bacteria was much

  Molar conductivity of different concentrations of thymine and adenosine in water , sodium acetate and ammonium chloride solution at different temperatures , 283. 15-323.15  K has been determined from direct conductivity measurements , examination of aqueous mixture of thymine and adenosine with Onsager equation reveal deviation from linearity at high concentration .This deviation was explained in term of molecular interaction . Ostwald dilution law also examined with the above mixtures lead to calculation of limiting molar conductivities and dissociation constants of both  nucleic acid in water , sodium acetate and ammonium chloride. The agreement between the values obtained for Onsager equation and Ostwald law was reaso

     This paper proposed several approaches for estimating the optical turbulence of the Earth’s atmosphere and their effect on solar images’ resolution using ground-based telescopes based on von Kárman, Kolmogorov, and modified von Kárman PSDs models. The results showed a strong correlation coefficient for the modified von Kármán model of atmospheric representation. As can be seen in the case where solar adaptive optics have been properly designed, they typically decrease aberration considerably and provide greatly improved imagery.