Emerging Trends in Science Education in a Dynamic Academic Environment

Emerging Trends in Science Education in a Dynamic Academic Environment highlights the changes that have occurred in science education particularly in institutions of higher learning in southern Nigeria. Impelled by the fact that most Nigerian Universities and Colleges of Education still adhere to the practices and teaching methodologies of the teacher-centered classroom teaching approach. Four research Questions and Hypotheses were raised. A total of 96 respondents were selected at random from the Faculty of Science and Education from seven (7) different Institutions of learning (3 Universities and 4 Colleges of Education) in Delta State. An internal consistency with a coefficient of 0.88 was established using Cronbach alph. A mean was used to answer the research questions. T-test statistics was used to test each hypothesis at 0.05 level of significance. The study revealed that there was an apparent upgrade from the chalk and board system to the use of the Magnetic White Board system, the use of slide projector based tutoring (SPBT) increases students understanding in science education, and that there is no significant difference between the attainments of teaching objectives when web-based training is administered by male science education tutors or by female science education tutors. The researcher recommends that Nigerian Government should embark on deliberate technological ventures that will not only develop the nation but also affect the academic environment positively. Keywords: Emerging Trends, Dynamic, Academic Environment

Gross &#945 and &#946 Activity Concentration and Estimation of Adults and Infants Dose intake in Surface and Ground Water of Ten Oil Fields Environment in Western Niger Delta of Nigeria

The oil and gas rich Niger Delta region of Nigeria is characterized by environmental degradation leading to environmental pollution from oil and gas activities. This study examined the gross α and β activity in thirty (river/stream, well and tap) water samples collected from ten oil fields in the Western Niger Delta region of Nigeria. The counting system employed in this analysis is the Gas-flow proportional counter {Eurisys Measure IN20 low- background multiple (eight) channel counter}. Gross alpha activity concentration range from 0.01±0.002 to 0.7±0.01 (0.15±0.003) Bql-1, 0.01±0.003 to 0.5±0.01 (0.1±0.003)Bql-1and 0.02±0.001 to 35.1±1.1 (4.1±0.1) Bql-1 while beta activity concentration ranged from 1.1±0.04 to 13.2±0.1 (6.0±0.1) Bql-1, 0.7±0.1 to 54.7±1.3 (8.9±0.2)Bql-1 and 0.7±0.03 to 151.2±1.8 (40.1±0.9)Bql-1 for well, tap and river waters respectively. Correlation value between α and β activities in well, tap and river water is 0.025, 0.047 and 0.512 respectively. The results show that except for the alpha activity in the tap water samples, the average natural activity concentrations of α- and β-emitting radionuclides in the samples are slightly above the WHO recommended limit. For all samples the gross β activities are higher than the corresponding gross α activities. The mean effective equivalent dose intake per year due to alpha activity in the water samples for adults and infants are: 76.4±1.8 and 20.9±55μSvy-1, 54.6±1.3 and 14.9±0.4 μSvy-1, and 2118±70 and 584±19.2μSvy-1 in well, tap, and river water samples respectively. The results obtained for dose intake are below the WHO recommended reference level of 0.1mSvy-1, except for the water sample from Uzere river. This study indicates that the water sources evaluated, especially the rivers, are contaminated radiologically. @JASE

Relative effectiveness of context-based teaching strategy on senior secondary students’ achievement in inorganic chemistry in Rivers State

This study adopted the quasi experimental research design to examine the relative effectiveness of context-based teaching strategy on senior secondary school students’ achievements in inorganic chemistry. The sample consists of 451 SSII chemistry students (224 males and 227 females) drawn from four out of 46 secondary schools in Port Harcourt Zone in Rivers State of Nigeria. Three research questions were answered and three null hypotheses were formulated and tested at the 0.05 level of significance. Stratified random sampling techniques were used in selection and classification of the sample into the experiment and control groups. Inorganic Chemistry Achievement Test (ICAT) was employed in data  collection. The instrument was validated and its reliability coefficient was 0.56. The ICAT instrument was administrated on both the pre-test and post- test. The data obtained from the administration of the instrument was analyzed using mean, standard deviation and analyses of covariance (ANCOVA). The study found out that context –based teaching strategy was significantly better than the expository method in enhancing students’ transfer of learning in inorganic chemistry. The result also showed that there was no significant difference in the mean achievement scores of male and female students taught inorganic chemistry using the same method. In the same vein, the rural students performed significantly better than their urban counterparts taught using the context-based teaching strategy. Based on the findings, recommendations were made among which were that context-based teaching strategy be adopted in teaching and learning of inorganic chemistry in the secondary and tertiary levels of the  educational systems.Keywords: Context-based, teaching strategy, students, achievement, inorganic chemistr

Evaluating the radiological health compliance of some beach environments in Delta State

Beaches constitute recreational and resort centres in the environment of which radiation is part. With respect to radiation protection practice, the International Radiation Protection bodies from time to time recommend certain exposure limits for different environments. In this study, a Raderlert 100 radiation meter was used to measure the gamma radiation levels in four beaches in Delta State, Nigeria. The purpose is to ascertain whether or not the radiation levels in these resort centres conform with international stipulations and consequently infer if their respective environments are radio logically health compliant such that personnel as well as specified members of the public (customers) are not at radiological risk. Results indicate a dose rate range of (0.010 – 0.015) mRh-1. These are generally higher than the 0.013 mRh-1 recommendation of ICRP. Results also indicate an Annual Effective Dose Equivalent AEDE range of (0.19 – 1.598) mSvy-1 which are higher than the recommended 1 mSvy-1 .Results further indicate an Excess Life Cancer Risk ECLR range of (0.64 – 1.74) x 10-3. These are higher than the 0.29 x10-3 world average. Thus it is concluded that the radiation levels in the environments of the studied beaches exceed international radiation regulatory stipulations.Therefore, in this their present states, these environments are radio logically unhealthy for their respective workers and members of the public.Keywords: Radiation levels; Beaches; Radiological health complianc

Quantification of Activity Concentrations and Radiation Hazard Indices in the Solid Minerals Exploration Fields of Benue State, Nigeria with Multivariate Statistical Approach

The quantification of activity concentrations of radionuclides and the radiation hazard indices in the exploration fields of Benue State have been carried out. Samples of the environmental matrix (soil and minerals) were collected from five mining sites of barite, limestone, lead, coal and salt in Lessle, Gboko, Anyin, Owukpa and Akuana communities. The concentrations of radioactivity was analyzed using NaI (Tl) γ-ray spectroscopy. Results showed that the concentrations of activity of the primordial radionuclides 40K, 238U, and 232Th for soil samples obtained ranged from 11.42 (Salt) – 1491.47 (Lead) Bq/kg, 12.87 (Barite) – 452.32 (Coal) Bq/kg and 6.78 (Coal)–108.41 (Barite) Bq/kg respectively. The mean value activity concentration of the radionuclides in the minerals samples at the mining sites were 10.58 – 623.36 Bq/kg, 1.97 – 540.33 Bq/kg and 2.13 – 25.28 Bq/kg for 40K, 238U, and 232Th respectively. The radium equivalent activity (Raeq), external hazard index, Hex, internal hazard index (Hin), representative index (Ig) and excess lifetime cancer risk calculated for soil and minerals samples compared favourably with the precautionary limits set by UNSCEAR. The excess lifetime cancer risk estimated for soil which was fairly insignificant compared with 0.05 prescribed by ICRP for low level radiation. The multivariate statistical (Pearson’s correlation and cluster) analysis showed some positive significant among 40K, 238U and 232Th, and with other radiological parameters in some mine fields. The study indicated that the minerals and soil samples from the mining sites will pose no major health risk to the public if used for industrial activities except for the salt minerals consumption

Evaluation of Background Ionization Radiation Level in Some Selected Dumpsites in Delta State, Nigeria

This paper reports on the evaluation of background Ionization radiation level (BIR) in some selected Dumpsites in Uvwie, Udu and Ughelli North Local government area of Delta State, Nigeria. Background ionization radiation measurements were carried out in five Dumpsites. An in- situ measurement was done using a well calibrated nuclear radiation meters Radalert-100 and a geographical positioning system (GPS). Readings were taken once in a week for one month in ten different locations within each of the Dumpsites. The mean background Ionization radiation values in all the five Dumpsites ranges from 0.017±0.006mR/hr to 0.018±0.007mR/h. All the background ionization radiation level obtained values exceeded the normal world average BIR level of 0.013mR/h. The mean Absorbed Dose Rate values range from 1.430mSv/y to 1.541mSv/y. The results showed that all the dumpsites yearly absorbed dose rate exceeded the 1.0mSv/y maximum permissible limit recommend for the public and non-nuclear industrial environment by International Council on Radiological Protection (ICRP, 1999). This research work indicated that the Dumpsites environment may have been impacted radiologically. This will pose some long-term health side effects on the workers and residents. Keywords: Evaluation, Ionization, Radiation, Dose, dumpsites

Surface relaxation and surface energy of face–centered cubic metals

Surface relaxation and surface energy are calculated for Rh, Ir, Pb, Ca, Sr, and Th, for three low-index surfaces, using the equivalent crystal theory (ECT) method. The surfaces are the (100), (110) and (111) faces. In this study, we only considered perpendicular relaxation where the relaxation was determined by the minimization of the total energy. The results obtained are analyzed with good agreement to experiment and first – principles calculations where available. Journal of Applied Sciences and Environmental Management Vol. 10(1) 2006: 37-4

Monitoring of specific activities of long-lived radioactive elements along the Mini- Okoro/Oginigba Creek, Port Harcourt

Presence and concentrations of radionuclides could be as a result of natural and human activities. This  study examined the associations and differences  among soil, sediment and water specific activities of long-lived radioactive element (LLRE). Gamma spectroscopy was used to measure the concentration of  the LLRE along the Mini Okoro/Oginigba Creek, Port Harcourt. Specific activities of three selected LLRE were derived. Correlation analysis was carried out to  examine associations among the specific activities across different substrates. A strong and a significant negative correlation exists between the specific  activities of Water 40K and Soil 232Th (r =-0.721, p<0.05); Water 238U and Soil 238U (r = -0.717, p<0.05) and Water 40K and Sediment 238U (r=-0.69,  p<0.05). Comparison using Mann-Whitney U test shows that, soil and sediment are similar in their specific activities with Z values of -0.408, -1.209 and  -1.021 (p > 0.05) for 40K, 232Th and 238U respectively. The concentration of solid samples (soil and sediment) is different from the liquid (water) samples. These associations can be attributed to some specific underlying factors. And in other to understand them there is need for more studies. © JASEMKeywords: Radionuclide; environmental monitoring; Niger Delta; Gamma spectroscopy; Environmental managemen

Survey of Background Ionization Radiation Level in Some Selected Automobile Mechanic Workshops in Uvwie LGA Delta State, Nigeria

Environmental radiation measurement was carried out in automobile mechanic workshops in Effurun, Uvwie Local government area of Delta State, Nigeria. An in-situ measurement was done using a well calibrated nuclear radiation meter (Radalert-100) and a geographical positioning system (GPS). The mean background Ionization radiation value in all the automobile mechanic workshops is 0.0167±0.002mR/hr  while the mean Equivalent  Dose Rate value is 1.428±0.002mSv/y. Both the background ionization radiation and equivalent dose rate levels obtained values exceeded the normal world average background ionization radiation (BIR) level of 0.013mR/h and 1.0mSv/y respectively (ICRP, 1999). This study revealed that the automobile mechanic workshops environment may have been impacted, but there is no immediate health implication. However, it will pose some long-term health side effects on the workers, residents and the environment. Keywords: Survey, Ionization, Radiation, Dose, Automobile, Mechanic, Workshop

Natural Radioactivity Levels in Surface Soil of Ogba/Egbema/Ndoni Oil and Gas Fields

The activity concentrations and the gamma-absorbed dose rates of the terrestrial naturally occurring radio nuclides viz. 226Ra, 232Th and 40K were determined in soil samples collected from twelve oil fields and their host communities, using gamma ray spectrometry. The soil activity ranges from 10.10 to 41.23 Bq/kg for 226Ra, 7.42 to 30.31 Bq/kg for 232Th and 92.42 to 482.79 Bq/kg for 40K with mean values of 19.16, 21.26 and 224.29 Bq/kg, respectively for host community soil. In the field soil sample, the activity concentration ranges from 16.27 to 52.19 Bq/kg for 226Ra, 9.72 to 34.13 Bq/kg for 232Th and 134.50 to 395.15 Bq/kg for 40K with mean values of 29.61, 17.41 and 262.63 Bq/kg, respectively. The concentrations of these radionuclides are compared with the values of the control samples and the UNSCEAR, 2000 standards of 35.0, 30.0 and 400 Bq/kg for 226Ra, 232Th and 40K respectively. The measured activity concentration of 226Ra, 232Th and 40K in soil is lower than the world average except in two oil fields that 226Ra and 40K exceeded the world average. Radium equivalent activities are calculated from the results to assess the radiation hazards arising due to the use of these soil samples in the construction of dwellings. All the soil samples have radium equivalent activities lower than the limit set in the UNSCEAR report (370 Bq/kg). The overall mean outdoor Absorbed Dose rate are 32.17 and 35.45nGy•h−1 respectively for host community soil and field soil samples. The corresponding effective dose calculated has mean values less than 1.0 mSvy-1, the limit set by WHO (2008). The hazard indices calculated were all less than unity (1) showing that all the soil/sediment samples sampled are still safe for building purpose since their radiological impact is minimal. The percentage contribution of each of these radionuclide are; 64.77% for radium-226, 3.13% for thorium-232 and 32.10% for potassium-40. The entire radiation hazard indices are within the acceptable limit therefore, no immediate health risk as a result of these radionuclide but continuous exposure may result to a significant health impact