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The effect of 2 bar steam pressure was studied on the Mm and Ms mineral sources of calcium sulphate dihydrate CaSO 4 .2H 2 O with and without milling respectively, which is than compared with autoclave calcium sulphate hemihydrate Mα ; α-hemihydrate, and CaSO 4 .2H 2 O annular; Ma by using FTIR spectroscopy technique at a wave number range 500-4000 Cm-1. The transmittance ratio; {T*-ratio = [ (T660/T1620) x 100] } for Mα, Ma, and Mm, was 96.96 %, 95.26% and 72.47% respectively compared with 82.70% at Mm which is treated with 2 bar steam pressure; MP2. The transmittance ratio; [T*-ratio] decreased in Ms after the steam pressure (1-6 bar) treatment. The effect of time 0.5 to 2.5 h on passing under 6 bar steam pressure on Mm displays the wave numbers at the range 2000-2500 Cm-1 which nearly reaching the same to spectrum of Mα. FTIR-spectrum at the range 500-1500 Cm-1 for AL-ahliyah gypsum (gypsum-Iraqi plaster); Mh which is calcium sulphate dihydrate heated in open vessel and Mm on treatment by 6 bar steam pressure for 2.5 h; MP6 was studies the destruction of this spectrum range comparing with Mα. The disadvantage of steam pressure on gypsum was observed by stretching of OH-group at the rang 3000-4000 Cm-1 in Mm, where the increasing of steam pressure in MP2 and MP6 caused in disappearing the wave numbers of 3609 and 3553 Cm-1 compared with the wave numbers appearing in Mα and Mh. This study showed the steam pressure may be used as a good parameter to change Mm to Mα which equivalent to the physical properties of dental material.

In the present work, studies the effect UV-radiation dose(1 J/cm²-360 J/cm²) with power 15 W to Lexan track detector thickness175 µm. Absorbance-A was measured at wavelength 300 nm and 305 nm by using UV-visiblespectroscopy and measure the transmission percent-T% and deviation at the wave number-w 940cm-1 by using Fourier infrared-FTIR spectroscopy. The relationship between the radiation dose of the UV-radiation (J/cm²) and the absorbance-Aat wavelength 300 nm and 305 nm and the wave number-w 940 cm-1 was calculate as a polynomial relation .The present study show that there is a possibility to use the detector Lexan to assessment doses of exposure to UV-radiation in the medical and environmental fields .

The solar photocatalytic degradation of diuron, which is one of the herbicides, has been studied by a solar pilot plant in heterogeneous solar photocatalysis with titanium dioxide. The pilot plant was made up of compound parabolic collectors specially designed for solar photocatalytic applications. The influence of different variables such as, H2O2 initial concentration, TiO2 initial concentration, and diuron initial concentration with their relationship to the degradation efficiency were studied. Hydrogen peroxide (H2O2) found to increase the rate of diuron degradation. The best removal efficiency of heterogeneous solar photocatalytic TiO2 system was found to be 46.65 % and for heterogeneous solar photocatalytic TiO2/ H2O2 system was found to be 80.65 %. Based on these results, the solar photocatalytic degradation by TiO2/ H2O2 system could be a useful technology for the treatment of effluents containing diuron.

The effect of gamma on nuclear track detector type PM-355 (at the dose range 200 to 1600 kGy) and thermal neutron (flux 10 5 n•cm −2 •s −1) was calculated by using of two irradiation methods. First method (G + N) was an irradiation PM-355 detector by gamma radiation and then irradiation by thermal neutrons, and another method (N + G) was irradiated by thermal neutrons and then gamma radiation. FTIR-spectroscopy was used to measure the change in deferent of transmission percent ΔT% at the wavenumber 1260 cm −1 with wavenumber 2962 cm −1 [ΔT%] 1260-2962 and wavenumber 1138 cm −1 [ΔT%] 1260-1138. The values of [ΔT%] 1260-2962 and [ΔT%] 1260-1138 were increasing with the increase of gamma irradiation with maximum response at 820 kGy and then drop after this dose until to 1600 kGy. This study determined the linear equations relation between the effect of gamma radiation on PM-355 detector and the change of [ΔT%] 1260-2962 and [ΔT%] 1260-1138, and this change appeared in (N + G) irradiation method better than in (G + N) irradiation method. The appearance of wavenumber 2964 cm −1 in (G + N) irradiation method referred to alkyl asymmetry C-H bond stretched out of skelated plane after changes in chemical structure of PM-355 detector by gamma or neutrons radiation.