formation constants for the conrdination of aniline pyridine dimethyl sulfoxide dimethyl formamide ethanol dimethylamine have been determined the cordination

              In the present work, poly methyl methacrylate (PMMA) doped with Rhodamine 6G was prepared. The spectral properties (absorption and fluorescence) of the films were studied at different concentrations (1x10^-5, 2x10^-5, 5x10^-5, 7x10^-5, and 1x10^-4mol/l). The investigated samples were made in the form of thin films. This was achieved by dissolving a certain weight of PMMA in a fixed volume of chloroform, composite films was with thickness (25.8μm) at room temperature. The achieved results were pointed out that absorption and fluorescence spectra have taken a wide spectral rang so when increased the concentratio

The estimation of the parameters of linear regression is based on the usual Least Square method, as this method is based on the estimation of several basic assumptions. Therefore, the accuracy of estimating the parameters of the model depends on the validity of these hypotheses. The most successful technique was the robust estimation method which is minimizing maximum likelihood estimator (MM-estimator) that proved its efficiency in this purpose. However, the use of the model becomes unrealistic and one of these assumptions is the uniformity of the variance and the normal distribution of the error. These assumptions are not achievable in the case of studying a specific problem that may include complex data of more than one model. To

The study was reflection of the impact of the widespread use of polymer Novolak composite reinforced  Glass fiber and Asbestos fiber once again with weight fraction 60% on the physical properties, which included (Hardness, Compressive deformation, compressive modulus of elasticity, Flexural modulus of elasticity, Resilience modulus, the maximum of Flexural strength, Flexural strain energy and Shear strength inner layers); it is known how much important the media as a source of bacterial contamination, which contributes directly or indirectly in the process of aging of these materials. These Novolak composite reinforced,  prepared by weight fraction of (10%) and (14%) of the Hexamethylene-tetraamine (HMTA) hardener material. It

  5-(mercapto-1,3,4-thiadiazole-2yl)α,α-(diphenyl)methanol have been synthesized by ring closer of potassium xanthate[which  have been prepared by reaction of benzilic acid hydrazide with carbon disulphide in potassium hydroxide] using conc.sulphuric acid at (0-5)°C scheme(I).       Their characterization was carried out from T.L.C, M.P, FT.IR and 1H-NMR.

The object of this work is to investigate the effect of the addition of methanol on the shelf life and color characteristics of novolak resin. Different percentages were added and two mechanisms were suggested for the addition. High ortho structure (1, 2-3) novolak resin was prepared and used in the above investigation. Experimental determination using FT-IR and UV-spectroscopy showed that on the addition of 30% of methanol and according to the second mechanism of addition novolak shelf life increased to 12 months without obvious decomposition and color change. It is suggested that methanol plays an important role in the inhabitation of the reactive sites on the resin that are responsible for the oxidation of the polymer when exposed to

The magnetic dipole moments and the root mean square radius have been calculated some the Fluorine (A= 17, 19, 20, 21) isotopes based on the sd-shell model using universal sd-shell interaction A (USDA). All studied isotopes are composed of 16O nucleus that is considered as an inert core and the other valence particles are moving over the sd-shell model space within 1d5/2, 2s1/2 and 1d3/2 orbits. The configuration of mixing shell model with limiting number of orbitals in the model space outside the inert core fail to reproduce the measured magnetic dipole moments. Therefore, and for the purpose of enhancing the calculations, the discarded space has been included the core polarization effect through the effective g-factors. The harmonic os

This research aims to study the radiation concentration distribution of the old District of Najaf (Iraq), where 15 samples were taken from featured sites in the District, which represents archaeological, religious, and heritage sites. Track detector CR-39 was used to calculate the concentration of three different soil weights for each sample site after being exposed for a month. Geographical information systems (GIS) were used to distribute the radioactive concentration on the sites of the samples, where two interpolation methods, namely the inverse distance weight method (IDW) and the triangle irregular network method (NIT), to study the distribution of the radioactivity concentration. The study showed that the western part of the district