Nuclear and Radiation

The level of implementation of quality control program (QCP) in diagnostic radiology facilities in Akwa Ibom state, Nigeria, was investigated. A total of thirty (30) diagnostic radiology centres took part in the study. A two part structured self completion questionnaire of thirty six items was the instrument used for data collection. Result shows that the level of implementation of quality control programme (QCP) in these diagnostic radiology facilities was low, importance of QC to the facility and radiation safety notwithstanding. This low level of implementation of QCP was identified with some fundamental factors namely, lack of radiation safety officers (RSO), lack of retraining programme for the medical personnel, lack of adequate funding, power and QC test equipment for the facilities. The aim of this investigation is to study the level of implementation of quality control programme which enhances radiation protection in diagnostic radiology facilities.

It is a well-known fact that solar resource or solar radiation varies spatially as well as temporally across the face of the earth. Hence, resource assessment is a preliminary step for all solar applications. In this study, a flat plate surface solar collector of dimension 2 m2, hinged on a horizontal support for quick adjustment of inclination from 0o to 80o was fabricated and marked out at 0.5o intervals on a telescopic leg graduated in degrees. Measurement of the solar radiation, varying degrees of inclination were taken between 11:00 a.m. and 4:00 p.m. for 7 days of each month at clear sky hours. The measurements were made for five months of the year in Tabriz, East-Azerbaijan Province, Iran. These months selected because they have maximum average solar radiation energy in Iran. At each 0.5 degree of inclination, the solar radiation intensity was replicated three times at each hour and the average value was taken. The flat plate was set truly facing south with an engineering prismatic compass. The result showed that the optimum tilt angle of a flat plate for maximum collection of solar radiation intensities in each month. This work also revealed that the average angle of inclination at which a flat plate surface solar collector will be mounted at fixed position in Tabriz is 31o approximately in studied months. The analysis indicated that when a flat surface was located at the forecasted optimum tilt angle for each of five months, solar radiation intensity was increased, when compared with solar radiation intensity harnessed by the same flat plate collector on other angles and under the same condition. Moreover this improvement impose no extra-cost. Comparison of the measured and calculated optimum values of tilt angle of a flat plate surface for trapping maximum solar radiation intensity for each of five months indicated a high correlation with R2 of 0.98 approximately.

Absorbed dose rate and annual effective dose estimated for occupational workers for Goldmines in Ghana that uses nuclear gauges in their operations and external ionizing radiation exposure during cargo radiographic inspections were measured as part of the authorization process for the use of ionizing radiations sources in Ghana. The measurements reported in this paper were made with portable radiation monitor which employed GM tube and was calibrated against secondary standard dosimetry system and a data for a five-year period (2010-2014) was compiled from the RAIS of the Ghana Radiation Protection Board. The average absorbed dose rate in air for Goldmine workers was 0.73µSv/h with an annual effective dose of 1.45 mSv while the average external radiation dose for workers and members of the public during cargo inspection was 0.23 µSv/h for Cobalt 60 scanners and 0.1 µSv/h for x-ray scanners and the annual effective dose for both workers and members of the public for Cobalt-60 and X-ray scanners were 0.46mSv and 0.2mSv respectively. It was concluded that the prevalent radiation levels did not pose any significant radiological health hazard to workers and members of the public.

In this work different samples of lipsticks were examined using (LIBS) to trace elements in them.

The Interacting Boson Model is applied to the even isotopes . Excitation energies, electromagnetic transition strengths, quadrupole and magnetic dipole moments, and ?(E2/M1) multipole mixing ratios, monopole transitions and mixed symmetry states have been described systematically. It is seen that the properties of low-lying levels in these isotopes, for which the comparison between experiment and IBM-2 calculations is possible, can be satisfactorily characterized by the Interacting Boson Model-2.

Field experiment conducted to measured Slippage, Effective field capacity, Field Efficiency, Soil Volume Disturbed and Specific Productivity Tillage in silt clay loam soil with depth 18 cm in Baghdad- Iraq. Split – split plot design under randomized complete block design with three replications using Least Significant Design 5 % was used. Three factor used in this experiment included Two types of plows included Chisel and Disk plows which represented main plot , Three Tires Inflation Pressure was second factor included 1.1 ,1.8 and 2.7 Bar, and Three forward speeds of the tillage was third factor included 2.35 , 4.25 and 6.50 km/hr. Result show chisel plow recorded best parameters performance.

This work is devoted to see how the phosphors concentration (N_P) effect on the band gap value in Light Dependent resistance (LDR) doped with phosphors. This effect is studied using visible light. The variation of the band gap with the different concentration is also studied in this work. In this work the dependence of the band gap on the phosphors concentration (N_P) and the magnetic field is discussed. We show that the gap width decreases with magnetic field approaching the critical value. The decrease in gap width has been calculated for (7 samples) Light Dependent Resistance (LDR) with different concentration ( N_P ) . From our results we found that the band gap in the light dependent resistance (LDR) doped with phosphors (P) depends not only on the donor’s concentration but also on the magnetic field, and the wave lengths of the visible light. The result of this work should provide useful guidance for the optical absorption in semiconductors.

Efforts to minimize dose delivered to critical organs of cancer patients and also to improve local tumour control have led to the development of High Dose Rate (HDR) brachytherapy procedures. The associated risks in HDR brachytherapy are relatively high, hence strict quality assurance requirements are needed. In this study, mathematical model has been used to compute the dose rate distributions around an Ir-192 HDR brachytherapy source. The calculations were based on separation of dose rates around the sources into transverse axis component and an anisotropy function. The two dimensional coordinate system for anisotropy functions was then transformed into a one dimensional system with radial distances from the centre of the source as constraints. The maximum average fit uncertainty was found to be 0.35% for the anisotropy functions. The maximum uncertainty in the calculated dose rate distribution around the source was 14.31%, which is less than the uncertainty quoted in published reports for other methods. The model is therefore an improvement over existing recommended systems for dose calculations and the results can be used as quality control tool to improve dose delivery to cancer patients undergoing brachytherapy.

The diffusion of slow electrons in Nitrogen ,Argon and Helium gases in uniform electric fields has been verified for ratios of electric field to pressure from 1.611 to 16.115,0.0322 to 0.3223 and 3.9131×10-3 t0 0.9767 (V/cm .Torr-1 ) respectively. These are calculations lead to a determination of the ratio of electron drift velocity to diffusion coefficient . By assuming a distribution in velocity of the electrons in the swarm, the Townsend energy factor KT and the mean electron velocity can be computed as a function of E/P, where E is electric field and P is the gas pressure, where the mean free path at unit pressure, the average energy loss per collision, and the gas kinetic cross section can be calculated. The results are presented in Figures forms. The obtained results appeared a good agreement with the experimental and theoretical data.

Values of dielectric constant ( ), dielectric loss ( ), relaxation time ( p), conductivity (?p) and moisture content of pulverized samples of Fenugreek were measured for different packing densities at 9.85 GHz microwave frequency and at different temperature ( 20?C, 35?C and 50?C). Experimental results on powders of different packing fractions (?r) were used to obtain transformation to 100% solid bulk using correlation formulae of Landau-Lifshitz-Looyenga and Bottcher. It is found that, there was fair agreement between the calculated values of dielectric parameters and the values obtained experimentally for solid bulk. This shows cohesion in the particles of Trigonellia Foenum-Graecum Linn. powder under investigation.