No abstract

The aim of this present study is to collect soil samples and some commonly consumed food materials in Ondo State, Nigeria such as tubers (cassava, Manihot esculent and yam, Dioscorea alata) samples and vegetables (waterleaf, Talinium triangulare and bitter leaf, Vernonia amygdalina) samples at some selected locations in Okitipupa, Ondo state, Southwestern, Nigeria in order to determine the following natural radionuclides (40K, 238U and 232Th) levels using a well calibrated NaI(TI) which is well shielded with a detector coupled to a computer resident quantum MCA2100R Multichannel. The transfer factors, annual absorbed dose rate and the annual effective dose in the samples collected were estimated. The results showed that the measured natural radionuclides were present in the mean concentrations of 323.79 ± 12.45 Bqkg-1, 81.87 ± 45.30 Bqkg-1 and 57.62 ± 18.04 Bqkg-1 for 40K; 11.76 ± 36.03 Bqkg-1, 4.67 ± 10.12 Bqkg-1 and 3.45 ± 2.10 Bqkg-1 for 238U and 9.66 ± 0.89 Bqkg-1, 3.07 ± 2.45 Bqkg-1  and 2.45 ± 0.92 Bqkg-1  for 232Th for soil, yam and cassava samples respectively. The results also showed that the radionuclides were present in the concentrations of 11.76 ± 36.03 Bqkg-1 and 9.66 ± 0.89 Bqkg-1 for 40K; 9.67 ± 8.53 Bqkg-1 and 7.87 ± 1.89 Bqkg-1 for 238U and 8.63 ± 6.08 Bqkg-1 and 6.58 ± 0.76 Bqkg-1 for 232Th for waterleaf and bitter leaf samples respectively. The soil-to-yam transfer factors were found to be 0.26, 0.40 and 0.32 for 40K, 238U and 232Th and soil-to-cassava yam transfer factors were found to be 0.18, 0.29 and 0.25 for 40K, 238U and 232Th respectively. The soil-to-waterleaf transfer factors were found to be 0.37, 0.82 and 0.82 for 40K, 238U and 232Th while the soil-to-bitter leaf transfer factors were found to be 0.32, 0.74 and 0.68 for 40K, 238U and 232Th respectively. The mean absorbed dose rate was 25.08 ± 0.57  and the mean annual outdoor effective dose was 46.17 . The annual effective dose reported for this present study area represents 65.95% of the world average value of 70.00 and 47.11% of Nigeria value of 98.00 mSvy-1  

This study investigates CNT-doped Cu2O thin film deposited by spray pyrolysis technique at a substrate temperature of 100°C. The samples were annealed at temperatures of 200°C and 230°C for 30 minutes. The effect of CNT doping on certain optical properties, such as extinction and absorption coefficients, a refractive index of doped Cu2O thin films were examined. The absorbance of the doped samples increases within the visible range and decreases in the ultraviolet range of the electromagnetic spectrum (EM). Both absorbance and extinction coefficients increased with temperature making the samples a good candidate for use as absorbance layer in device fabrication. In addition, there was an increase in direct bandgap with the increase in CNT concentration of the thin films. The result of the study revealed that CNT doping has a significant effect on the properties of Cu2O.

Nanoparticles of a transitional metal oxide such as Copper (II) oxide or cupric oxide have gained considerable interest in the research and development community due to the corresponding conventional materials' extremely different characteristics. Hence, this study aimed at characterizing Copper (II) oxide nanoparticles synthesized through a direct green chemical approach using the outer leafy cover of the maize husk. The fresh maize husk's optical absorption spectrum shows broad peaks that were cantered around 209, 241, and 331 nm, which are the characteristic of flavonoids. The structural analysis shows the formation of Nantokite with a face-centered crystal structure, which has crystalline peaks (111), (220), (311), and (331) at 2θ = 28.5, 47.4, 56.28, and 76.6, respectively. In contrast, the spectrum of Copper (II) oxide showed a base-centred monoclinic crystal structure with lattice parameters: a= 4.688, b = 3.4229, c = 5.1319 and β = 99.91. In conclusion, nanoparticles' synthesis using aqueous corn husk extract was successfully synthesized and characterized. This environmentally friendly approach is a simple, environmentally friendly, inexpensive process and is reproducible.

This study was carried out on entrance skin dose (ESD) (Radiation) measurement and evaluation (for all age groups) at the State Specialist Hospital, Okitipupa, Ondo State, Nigeria. Entrance skin doses for randomly selected patients between 0-4 years, 5-9 years, 10-17 years and above 18 years old undergoing X-ray chest (Poster Anterior) examinations were measured and evaluation of the source-to-skin distance (SSD) records for the patients during the x-ray chest examinations were carried out. The mean ESD reported for chest PA projections were 66.43 µGy, 105.10 µGy, 215.76 µGy and 291.81 µGy respectively for age range 0 - 4 years, 5 - 9 years, 10 - 17 years and above 18 years. The ESD values reported in this present study were same with the NRPB recommendations of year 2000 of 50 µGy for newborn to 1-year-old, 70 µGy for 5 years and 120 µGy for 10 years old children. The values reported for age 1 to 4 years were lower than 0.1 mGy recommended and the mean ESD for age 5 to 9 years for chest PA examination was 0.11 mGy which is lower than the recommended 0.12 mGy. However, other values reported in this present study were compared with the guidance levels set by the International regulation bodies and were found to be within safe limits and they do not pose any significant health risk to the patients of all age ranges or the health workers. The effective radiation doses (ERDs) for all the age groups were computed, and by comparisons, it was found that the radiation risk factors (RRFs) are relatively low.