Samples prepared by using carbon black as a filler material and phenolic resin as a binder. The samples were pressed in a (3) cm diameter cylindrical die to (250)MPa and treated thermally within temperature range of (600-1000)oC for two and three hours. Physical properties tests were performed, like density, porosity, and X-ray tests. Moreover vicker microhardness and electric resistivity tests were done. From the results, it can be concluded that density was increased while porosity was decreased gradually with increasing temperature and treating time. In microhardness test, it found that more temperature and treating time cause more hardness. Finally the resistivity was decreased in steps with temperature and treating time. It can be concluded that these variables may increase the graphitizing degree, and minimizing in interplanar distance for samples comparing with ideal one, when these variables may increased.
Superconducting thin films of Bi1.6Pb0.4Sr2Ca2Cu2.2Zn0.8O10 system were prepared by depositing the film onto silicon (111) substrate by pulsed laser deposition. Annealing treatment and superconducting properties were investigated by XRD and four probe resistivity measurement. The analysis reveals the evolution of the minor phase of the films 2212 phase to 2223 phase, when the film was annealed at 820 °C. Also the films have superconducting behavior with transition temperature ≥90K.
Ti6Al4V thin film was prepared on glass substrate by RF
sputtering method. The effect of RF power on the optical properties
of the thin films has been investigated using UV-visible
Spectrophotometer. It's found that the absorbance and the extinction
coefficient (k) for deposited thin films increase with increasing
applied power, while another parameters such as dielectric constant
and refractive index decrease with increasing RF power.
Thin films of Mn2O3 doped with Cu have been fabricated using the simplest and cheapest chemical spray pyrolysis technique onto a glass substrate heated up to 250 oC. Transmittance and absorptance spectra were studied in the wavelength range (300 -1100) nm. The average transmittance at low energy was about 60% and decrease with Cu doping, Optical constants like refractive index, extinction coefficient and dielectric constants (εr), (εi) are calculated and correlated with doping process.
In the present study, the growth and total lipid contents of two oleaginous fungal isolates Aspergillus terreus, Aspergillus fumigatus were compared in different nitrogen and organic carbon sources. Artificially the fungi were cultured on media consisting of various mono- or di- or polysaccharides and peptone or yeast extract as elementary sources for carbon and nitrogen, respectively. Media containing sucrose /yeast extract or glucose/ yeast extract were the most effective for lipid production from fungal, during two weeks incubation period, the highest biomass of dry weight was (19.6 , 18.8) g / L , (25.8 , 30.5) g /L and lipid yield (1, 0.97 )g/L, (0.65, 0.65) g/ L for two isolates Aspergillus terreus
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Tigris River is one of the main important surface water resources in Iraq. This necessitates continuous study of its quality . The present study is concerned with the characteristics and quality of Tigris water passing through in Baghdad city. (eight) samples were collected from the river in the area Grea't City. The study periods were carried over four season, which has been sampled once represent the every season. First sampling 12-11-2012 represent the autumn season The second sampling 20-1-2013 to represent the winter season. The third in 25-3- 2013 to represent the Springer season. The fourth during 29-5-2013 to represent the summer spring season. In order to specify the water quality, a group of physical and chemical analyses have bee
... Show MoreAgricultural chemicals on a large scale of use throughout the world, and there are many studies about these chemicals and its disadvantages, but most of them were limited to its impact on mammals such as rodents in determine. This study was designed to determine the impact of these chemicals on DNA damage for E. coli bacteria from Iraq. The DNA is similar in terms of structure and function in all living organisms with a different in number and sequence of the nitrogenous bases among living organisms. This study showed that snails and slugs killer material Metaldehyde are strongly bind with the DNA extracted from bacteria, and herbicides Glyph
... Show MoreThe study aimed to evaluate whether Enalapril has any effects on the testicular tissue of the albino male mice which received or did not receive treatment with Enalapril.
Mature mice were divided into three groups: control group which fed with 0.1mg of normal saline, the second group was orally fed with 10 mg/Kg of Enalapril drug while the third group was fed with 20 mg/Kg of drug, one time a day for 30 successive days by using gavage tube (0.1ml). The histological sections were performed and the slides were examined using the light microscope.
The present study result of light microscopic images of mice testes cross sections which treated with 20 mg/Kg of Enalapril showed coagulated necrosis on spermatogonia
... Show MoreBobbin friction stir welding (BFSW) is a variant of the conventional friction stir welding (CFSW); it can weld the upper and lower surface of the work-piece in the same pass. This technique involves the bonding of materials without melting. In this work, the influence of tool design on the mechanical properties of welding joints of 6061-T6 aluminum alloy with 6.25 mm thickness produced by FSW bobbin tools was investigated and the best bobbin tool design was determined. Five different probe shapes (threaded straight cylindrical, straight cylindrical with 3 flat surfaces, straight cylindrical with 4 flat surfaces, threaded straight cylindrical with 3 flat surface and threaded straight cylindrical with 4 flat surfaces) with various dimensio
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In this research study the effect of fish on the properties optical films thickness 1200-1800 and calculated energy gap Basra direct transport permitted and forbidden to membranes and urged decreasing values ??of Optical Energy Gap increase fish included accounts optical also calculate the constants visual as factories winding down and the refractive index and reflectivity membranes also by real part and imaginarythe dielectric constant
The effect of the annealing on the optical transmission , absorp tion coefficient,
dielectric constants (ε
r
),( ε
i
) ,Skin depth and the optical ener gy gap of (ZnO)x(CdO)1-x thin
films with (x=0.05) deposited on preheated glass substrates at a temperature of (450 C°) by
chemical pyrolysis technique were performed . These f ilms show direct allowed inter band
transition that influenced by annealing at ( 450 C°) for two hours . And it also found that the
optical ener gy gap has been increased fro m about (2.50 eV) before annealing to about (2.65
eV) after annealing , fro m the analysis of the absorp tion and transmission sp ectra in the
wavelength range (380-900nm) . The results show t