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Distribution of radionuclides and assessment of risk exposure to the miners on a kaolin field
Get PDFMining of kaolin deposits are common in Nigeria without considering the background radiation in such environment and the health risks it might pose on the miners. In this study, in-situ measurements of the naturally occurring radionuclides were carried out with the aim of determining the distribution of these radionuclides on the mining field and estimation of the hazard indices exposure risks (γ- and α-radiation risks) to the miners. The study was achieved with the aid of gamma ray detector Super-Spec (RS-125) and global positioning system. The detector used has ability to measure activity concentrations of 238U, 232Th and 40K and gamma doses. For the purpose of this study, only the concentrations of the three radionuclides were considered. For each location, measurements were taken four times, while its mean value was estimated for better accuracy. In all, nineteen locations were occupied in order to cover the study area. Basic kriging method was adopted for the production of spatial distribution of these radionuclides and their corresponding γ- and α-radiation hazard indices. The mean values of 238U, 232Th and 40K are 46.7, 71.8 and 108.7 Bq kg-1 , respectively. When compared to the global standard, it was revealed that 238U and 232Th are greater than the global standard, while 40K fall below the permissible limit. The γ- and α-radiation exposure risks estimated revealed that the mean values of Iγ and Iα are 0.6 and 0.2 respectively. Though the estimated γ- and α-radiation indices showed that the kaolin field is safe for the miners, periodic check is required in order to monitor the rate at which these natural primordial radionuclides (238U and 232Th and their progenies) are being enhanced
Preparation and characterization of a new adsorbent from raphia taedigera seed
Get PDFStaff PublicationThere has been widespread research and engagement in recent years on the
use of plant material in preparing porous carbon for wastewater treatment. In
this study, new biochars (BCs) impregnated with 0.1 M sulphuric acid (RTA)
and 0.1 M sodium hydroxide (RTB) were prepared. The BCs and raw seed
[RTR] were characterized using scanning electron microscopy (SEM), Four ier -
transform infrared (FTIR) spectrophotometer, and
thermogravimetric/Differential thermal analyser. [TGA/DTA) to determine
their morphology, spectral bands and thermal behaviour respectively. RTR
showed a scattered aggregated surface microstructure, while both RTA and
RTB gave aggregated rough surfaces with high number of pores. The FTIR
analysis showed significant changes in term of band shift, bands
disappearances, and new band formations due to pyrolysis and activation of the
BCs. The results of the TGA/DTA revealed that RTA and RTB have better
thermal stability than RTR, with the maximum degradation temperature of
RTR, RTA, and RTB occurred at 3800C, 4250C and 4100C respectively.
Adsorption efficiencies ranged from 81.671 to 99.743% for performance
evaluation on the BCs using different adsorbent dosages and the initial
concentrations of methylene blue solutions. These preliminary investigations
suggest that biochars prepared from Raphia taedigera seed can be used for
methylene blue removal from wastewate
Investigating and Proffering Solutions to the Information Seeking Behaviour of Immigrants in the United Kingdom
Get PDFThe aim of this study is to investigate the information seeking behaviour of immigrants in the United
Kingdom, main focus was on the asylum seekers. The research method was extended literature review
type. The literature review takes the shape of a systematic review. Past studies were used to know
what has been done about the study and what is missing, which helped the researcher in creating the
research questions. Data were collected from different findings of several researchers, the analysis
of secondary authors were collated to form the findings of this research. International studies were
mostly used because more research has been done internationally than in the UK. The limitation of
the study was trust issues, the findings cannot be trusted based on the research method used. The
findings, answer the research questions of information needs, information source and information
barriers of immigrants. The researcher provided some recommendations for informational
professionals and librarians as how to solve the research problems. The role of the Library was also
discussed extensively as to help immigrants upon arrival in a new environment
Influence of Gender Differences on Usage Patterns of Electronic Information Sources among Undergraduates of Selected Universities in Southwest, Nigeria
Get PDFThis research work investigated the influence of gender differences on usage patterns of electronic information
sources among undergraduates in Nigeria. The study adopted a descriptive survey research design. The population was made up of randomly selected undergraduate students of Ekiti State University (EKSU) and University of Ibadan (UI). Data were generated through the use of questionnaire designed to elicit responses from respondents and analysed using descriptive statistics method of frequency counts and percentages. However, out of five hundred (500) copies of questionnaire administered, four hundred and twenty one (421) were returned which represents 84.2% response rate for the study. Findings revealed that there is no basis for gender differentiation in the use of electronic information sources as gender gap in electronic resources usage appeared negligible. However, it was recommended that university libraries in Nigeria should continue to give equal opportunities to both sexes in term of training and orientation on the use of e-resources among other recommendations
Assessment of laboratory capacity of public secondary health facilities in performing assay of selected epidemic-prone diseases in Oyo State, Nigeria
No full textArticle in Press awaiting full bibliographic informationThis study assessed the capacity of public secondary facility-based laboratories in conducting diagnostic tests for selected epidemic-prone diseases in Oyo State, Nigeria. A descriptive cross-sectional study was conducted in 17 secondary facility-based laboratories in Oyo State. Capacity was assessed on a 100-point scale in which scores were rated low (≤49%), fair (50–79%) and good (≥80%). Diagnostic testing capacity for bacterial meningitis, cholera, and measles was “low” in all the laboratories. The reasons reported for laboratories not conducting diagnostic tests for the selected diseases included inadequate instruments, unavailable reagents, and clinicians' failure to request those diagnostic tests. Laboratory capacity to perform diagnostic tests for the selected diseases was low in Oyo State secondary hospitals. There is a need for the provision of modern instruments and reagents, as well as clinician laboratorian quality assurance programs, to improve diagnostic services relating to the selected diseases
lkaloid extracts from Bitter leaf (Vernonia amygdalina) and Black nightshade (Solanum nigrum) inhibit phosphodiesterase‐5, arginase activities and oxidative stress in rats penile tissue
No full textThe erectogenic potential of alkaloids extracted from Bitter leaf (Vernonia amygdalina) and Black nightshade (Solanum nigrum) was investigated in this study. Fresh leaves obtained from Bitter leaf and Black night shade were air‐dried, pulverized, and extracted for alkaloids. The inhibitory potential of the alkaloid extracts on arginase and phosphodiesterase‐5 (PDE‐5) activities in rats penile tissue was determined in vitro. The antioxidant properties were also evaluated and the constituent alkaloids quantified using GC‐MS. The alkaloid extracts inhibited arginase (0–30.51 μg/ml) and PDE‐5 (0–133.69 μg/ml) activities in a concentration‐dependent pattern. Similarly, the alkaloid extracts inhibited Fe2+‐induced lipid peroxidation in rats penile tissues, scavenged DPPH, OH, and NO radicals as a function of concentration. GC‐MS characterization revealed over 20 alkaloid compounds. The inhibition of PDE‐5‐, arginase‐, pro‐oxidant‐induced lipid peroxidative‐, and free radicals‐scavenging activities by the alkaloids is suggestive of putative mechanisms underlying their therapeutic use for managing erectile dysfunction in folklore medicine
Artificial neural network based autoregressive modeling technique with application in voice activity detection
Get PDFA new method of estimating the coefficients of an autoregressive (AR) model using real-valued neural network (RVNN) technique is presented in this paper. The coefficients of the AR model are obtained from the synaptic weights and adaptive coefficients of the activation function of a two layer RVNN while the number of neurons in the hidden layer is estimated from over-constrained system of equations.
The performance of the proposed technique has been evaluated using sinusoidal data and recorded speech so as to examine the spectral resolution and line splitting as well as its ability to detect voiced and unvoiced data section from a recorded speech. Results obtained show that the method can accurately resolve closely related frequencies without experiencing spectral line splitting as well as identify the voice and unvoiced segments in a recorded speech
Comparative Analysis of Machining Stainless Steel using Soluble and Vegetable oils as Cutting Fluids
Get PDFIn this study, the performance of groundnut oil as an alternate cutting fluid was compared with that of soluble oil during machining of stainless steel. The temperature at the cutting zone, surface roughness and the chip formation were monitored under the two cutting conditions (soluble oil and vegetable oil). The machining parameters used were cutting speed (75 – 135 rev/min), feed rate (0.01 – 0.05 mm3/mm) and depth of cut (0.01 – 0.08 mm). The experiment was designed using Taguchi orthogonal array of Minitab 18 which generated a 9 run machining parameter mix for the experimentation. The Physiochemical properties of the various fluids were also analyzed to determine the properties and constituent elements of the cutting fluids. The actual machining of the stainless steel bar was done using a Colchester mastiff lathe machine. Results show that feed rate and cutting speed had the most significant effect on surface roughness during machining of stainless steel both with groundnut oil and soluble oil. Soluble oil was a better coolant but poorer in lubrication as vegetable oil reduced surface roughness more when used. Surface roughness value improved from 9.21μm during machining with soluble oil to 3.84μm during machining with groundnut oil which represented a 58.3% improvement. Hence, vegetable oil is therefore recommended as good alternative cutting fluid to soluble oil during machining of stainless steel
NITRILE-METABOLIZING BACTERIAL STRAINS ASSOCIATED WITH MUNICIPAL WASTE TIPS IN THE LAGOS METROPOLIS, NIGERIA
Get PDFCyanide is one of the dominant pollutants in the environment. This study aimed at exploring the potential of microbes in the detoxification of cyanogenic substances. Bacillus sp. WOD8 KX774193 and Corynebacterium sp. WOIS2 KX774194 strains were isolated from solid waste leachates. The doubling times of strain WOD8 and strain WOIS2 when grown on glutaronitrile and benzonitrile (without supplementing glucose) were 12.2 and 7.86 d (specific growth rate, μ: 0.057 and 0.088 d-1) and 15.75 and 13.33 d (specific growth rate, μ: 0.044 and 0.052 d-1) respectively. Also, strains WOD8 and WOIS2 grew on glutaronitrile and benzonitrile (with supplementing glucose) with doubling times of 9.76 and 7.62 d (μ: 0.071 and 0.091 d-1) and 10.5 and 8.15 d (μ: 0.066 and 0.085 d-1) respectively. The results from the present study suggest that the nitrile-metabolizing capabilities of these bacterial isolates can potentially be explored for the degradation and bioremediation of nitrile contamination in the environment
Assessment of radiogenic heat generation in a flood plain of crystalline Basement rocks
Get PDFConcentrations of radioelements in a flood plain of Crystalline Basement Complex are determined, with the aim of assessing the radiogenic heat produced in the study area. Ten soil samples are collected for analysis using Inductively Coupled Plasma Mass Spectrometry technique from ACME Laboratories. The radiogenic heat contributions by each radioelement in the flood plain varied from 95.70 to 393.37 ρw/kg; 71.68 to 642.56 ρw/kg; and 0.0088 to 0.0188 ρw/kg for uranium, thorium and potassium respectively. However, the total radiogenic heat production varied from 167.39 to 1034.9 ρw/kg, with thorium being the major contributor to the total heat generated in the study area. Nine locations in the study area are characterized by Low Heat Potential (LHP), while the remaining one is characterized by Moderate Heat Potential. On average, the study area could be classified as LHP, which is in agreement with some of the studies in crystalline terrain of Nigeria.Conference or Workshop Item (Paper)
Journal of Physics: Conference Serie