Journal of Basrah Researches (Sciences)

The electrical properties investigation for poly alpha naphthyle acrylate doped with Ioden (I2) films was carried out for films prepared by cast method.Conduction processes were analysed through measuring (Current – Voltage) and (Conductivity – temperature) relationships in the voltage and temperature ranges (1-120) V and (308 -373) K respectively. The resistance of the doped films is found to have a negative thermal coefficient. The activation energy at temperature (308 -373)K was about (0.6)eV is found from the ohmic region of the dark (current – voltage) characteristic. The conductivity at temperature 308 was equal to 5.57×10-12 (S.cm-1).The deviation from ohm's law has been analysed in term of the available conduction theories, ionic conduction mechanism was concluded.

The aim of this research is to study the effect of fiber glass on the thermal insulation property of polyester resin . Different amounts of fiber glass were added to the polyester resin with hardener then cast as sheet of composite material of dimension (20*20*0.3) cm3 with different fiber glass weight percentage : ( 0% , 4 % , 8 % , 12 % , 16 % , 20 % ) of the total weight. The thermal conductivity was calculated by using Lee’s Disk method . The mean value of five measurements of thermal conductivity ( k ) for each specimen was measured , also the hardness of the specimens was measured by using shore method type D and then sketch the relation between thermal conductivity and hardness with the percentage of fiber glass. The results showed that the thermal conductivity (k) of polyester decreased (which mean thermal insulation increased ) with an increase of fiber glass percentage , and the hardness increased with the increase of fiber glass percentage due to the restricted movement of the chain end of polymer .

Nanostructured ZnO thin films have been synthesized by Sol Gel process. The ZnO precursors were prepared by using zinc acetate dehydrate and a mixed solution of monoethanolamine and ethanol, and were prepared with Zn2+ concentration 0.5mole. The films were deposited on glass substrates by spin coating at 3000 rpm for 30s at room temperature. These films were postheated at 400oC for 1h at air. ZnO thin films have a polycrystalline and wurtzite structure. The crystallite size was determined by X-ray diffraction using Scherrer method. The crystallite size of ZnO thin film was 23.4nm. The transmittance spectra of ZnO films were 85% in the visible region from 600 to 800nm. The energy band gap is found to be 3.24 eV for ZnO film.

ZnO nanoparticles were successfully synthesized from solution phase of zinc acetate and ethanol in microwave oven. The time of preparation was decreased from several hours to several minutes due to using microwave oven.XRD of prepared ZnO Nanoparticles was study and show it has hexagonal ZnO phase with particles size in the range of 16 nm. Optical properties of ZnO nanoparticles was study using UV-vis spectrophotometer ,the absorption spectra shows the blue shift of energy band gap and by using effective mass model we estimate the particle size of ZnO powder which equal 7nm.

The AC electrical conductivity σAC ,dielectric constant Є΄ and dielectric loss Є˝ for poly (Crystal Violet Terephthalate ) have been studied at frequencies that range from 100 KHz to 1300 KHz and in temperature range ( 22 –70 ) °C. The experimental result shows that the value of dielectric constant Є΄ slightly increases with increasing frequency which indicates that the major contribution to the polarization comes from orientation polarization , also the value of dielectric constant Є΄ increased with increasing temperature , and is due to the greater freedom of the movement of the dipole molecular chains .The dielectric loss Є˝ and AC electrical conductivity σAC increase with increasing frequency, such as Є and σAC dependant on frequency.

We demonstrate experimentally that optical beam using CW low power (7(mWatt 6328 A0 laser beam is self-focused upon passing through organic dye cells (Neutral Red (3- amino-7-dimethylamino-2-methyl phenazine))

In this paper, we use the principles of eigenvalues and eigenvectors for the first time in the field of Arabic word segmentation. In the beginning, the segmentation algorithm calculates eigenvalues and eigenvectors for each input speech signal, and selects the largest values. The values of final vector are used for linear separation to consonant regions and vowel regions by using threshold value which calculated from the final vector itself. The segmentation points are extracted efficiently and determine the beginning and the end points of each phoneme of the input word signal in high accuracy. Experimental results for a number of isolated Arabic words for a number of speakers ( males and females) given in the paper show that the algorithm determines the beginning and the end points for each phoneme in the input speech signals efficiently.

An isolate of the fungus Fusarium chlamydosporum was exposed to different concentrations (10, 20, 40, 60, 80, and 100ppm) either of silver Ag+1 or of cobalt Co+2 ions, singly and a mixture in vitro and the growth rate (colony diameter) of the fungus was measured. The results showed that the toxic effect of Ag+1 ions was more than those of Co+2 ions and at concentration 100ppm Ag+1 ions gave the highest effect on the fungus growth. The results also showed that the mixture of Ag+1 and Co+2 ions has a synergistic effect on the growth rate of the fungus. In general, the effect depened on the heavy metal ions concentration and the exposure periods

The present study includes toxicity experiments carried out under laboratory conditions for ( 24 , 48 , 72 , 96 and 120 ) hours period by using renewal toxicity test system to determine the comparison of crude oils , dispersant mixtures and the water – soluble fraction to crab Sesarma boulengeri male and female net weight (2.655 ±0.5) gm which is found in Hamdan canal , a branch from Shatt Al _Arab River . The median lethal time (LT50) has been recorded for each concentration and median lethal concentration (LC50) has also been recorded within (120) hours of exposure to concentrations of ( 2.5 , 5 , 10 and 20 ) ml / l crude oil . The toxicity experiments show that the dispersant mixture water soluble fraction ( WSF ) vary widely in their toxicity and accumulation of petroleum hydrocarbons to the specimen tested and slightly less toxic to oil – in water dispersions ( OWD ) . The mortalities increased with the increase of the concentrations and with the increase of time . The female tend to accumulate petroleum hydrocarbons slightly more than the male , and that the individuals had an ability to dispose large amounts of oil pollutants after their recovery in clean water .

أيمان علي سعيد

The theortical calculations for pyrocatechol with and without intramolecular hydrogen bonding (I, II and III) were performed by quantum chemical methods. The optimized structures of the compounds(I,II and III) were obtained by using the Density functional theory (DFT /Slater) level of theory using the basis set 6-311G(d,p). Study Showed that the value of total energy for form (II) is less than compounds (I and III), which strongly indicates the stability of form(II). Also the dipole moment of form (II) is high compare with the forms (I and III). The calculation also shows a decrease in the length of hydrogen bond in form (II) compare with that of form (III). The thermodynamic calculation were carried out for (I,II andIII)and showed that favorable state is form (II)( more stable).