NORMs distribution in coastal soils and sediments of River Yobe, north-eastern Nigeria: an evaluation of the potential radiological hazards

A preliminary study which aimed to establish a reference data on naturally occurring radioactive materials (NORMs) for River Yobe has been conducted. Soil and sediment samples were collected along the coastal areas of the river and analyzed to determine the specific activities of NORMs such as 238U, 232Th and 40K. Gamma spectrometry technique using NaI (Tl) detector was employed to determine the specific activities f the natural radionuclides. The mean activity concentration in the soil samples for 238U, 232Th and 40K were found to be 23±1.5, 36±2.5 and 395±9.1Bq kg−1 and for the sediment samples are 60±2.6, 45±3.6 and 324±6.8Bq kg−1 respectively. These values, in some cases exceed the world reference values of 30, 35 and 400 Bq kg−1 for 238U, 232Th and 40K respectively. Parameters of radiological hazard, were also estimated based on specific activity of the radionuclides to assess the radiological impacts due to exposure on the users of the river. The results were found to be within the worldwide recommended safety limits.Keywords: Annual effective dose, NORMs,238U.232Th.40K. River Yob

Carbon Monoxide and Carbon Dioxide Level Distribution of Rojhelat Cafe in Duhok City

There are a few data of toxic concentrations and their distribution of cigarrete and Shisha smoking in Café. Therefore, the aim of this study is to know the concentration and the distribution of both CO and CO2 gases in Rojhelat Café in Duhok city. Both gases have been measured in different positions of Café before opening and until closing the place. Furthermore, the distributions of gases at different places and different elevation have been measured. The results showed that the effect of shisha on producing gases is more than cigarrete. We found that the toxic gases in Café were too high. This study will help the Café manufacture how to design the building such Café for air conveyor and condition

Predisposing Factors in Post Endoscopic Retrograde Cholangiopancreatography Pancreatitis

Objective: To ascertain the prevalence of risk factors in pancreatitis after endoscopic retrograde cholangiopancreatography at Isra University Hospital in Hyderabad. Methodology: This descriptive case series study was done at the gastroenterology department of Isra University Hospital, Hyderabad, from September 2018 to March 2020. Patients aged 18 to 50 years, both genders, and diagnosed with post-ERCP pancreatitis were included. All the patients were undergoing an ERCP procedure. The procedure was done under conscious sedation or propofol where needed. The serum amylase level was assessed in all patients at 4 hours. Patients had been considered to have post-ERCP pancreatitis if they developed new or worsening pain of abdomen and had a threefold increase in serum amylase. All the cases were assessed regarding risk factors in pancreatitis after endoscopic retrograde cholangiopancreatography. All the data was recorded in the proforma. Results: The mean age of the patients was 42.7 years. The majority of the patients (65.47%) were females and 32.90% were males. The mean duration of pancreatitis was 3.1 days. Sphincter of Oddi dysfunction was found in 17.1% of cases. Precut papillotomy was done in 18(23.7%) cases. Repeated pancreatic duct injury was seen in 10(13.2%) cases. No significant difference was found in the effect of modifiers on predisposing factors in post-endoscopic retrograde cholangiopancreatography pancreatitis, p-values were almost insignificant. Conclusion: Cannulation attempts, Sphincter of Oddi dysfunction, precut papillotomy, repeated pancreatic duct injection, and female gender were observed to be the predisposing factors in post-endoscopic retrograde cholangiopancreatography pancreatitis

Design and simulation of a PI controller system with frequency response

It is convenient to have a minimum number of parameters that are tuned to control a system.  Proportional-integral-derivative (PID) controllers have this specification and are now daily used in a different field of application especially in industrial control system.  To get the frequency response of such controller to any disturbance signal an appropriate design technique is needed.  Here a PI controller system is implemented and simulated using NI Multisim (13.0) software. We study the frequency response of a PI controller. The results and calculations show that the designed PI controller has very fast (above than 10 kHz) response to any disturbance. We show a large match between the simulation and the experimental part. A bode plot that give us the frequency response of the system has been calculated and measured. The implemented work is important for many applications especially in the field of atomic force microscopy (AFM), scanning tunneling microscopy (STM) and other industrial control system that need fast control

Determination of surface radiation dose-rate in the environment of Kelantan State, Malaysia

Measurements of environmental surface radiation dose rate in Kelantan state, Malaysia was carried out using a portable hand held radiation survey meter and Global Positioning System (GPS). The surface radiation dose rates ranged from 44 to 500 nGy h-1. The measurements were done based on geology and soil types of the area. The mean radiation dose rate was found to be 209 ± 8 nGy h-1. Few areas of relatively enhanced activity were located in Pasir Mas, Tanah Merah and Jeli districts which have external gamma dose rates between 300 to 500 nGy h_1. An Isodose map of the state was produced using ArcGIS10 software version 10.1. To evaluate the radiological hazard due to terrestrial gamma dose, the annual effective dose equivalent (AEDE), the mean population weighted dose rate and cancer risk factor were calculated and found to be relative excess lifetime cancer risks were 1.280 mSv y-1, 18 mSv and 1.04×10-3 respectively

Nigeria research reactor-1 : vertical detector efficiency calibration using conventional and semi-empirical approach for large samples NAA implementation

Detector efficiency calibration is mandatory for accurate measurement of induced activity in irradiated samples and for safe operation of the reactor with minimal uncertainty. This paper reported the efficiency calibration of vertically dIpstick High Purity Germanium detector, installed at the Centre for Energy Research and Training, Ahmadu Bello University Zaria for the purpose of large sample Neutron Activation Analysis (NAA) using Nigeria research reactor-1 (NIRR-1). The performance of the detector was evaluated for the radioisotope activity measurements during the reactor operation for large samples neutron activation analysis. The detector performance in terms of radioisotopes detection ability was inspected using the standard conventional and semi-empirical approaches. The full energy peak efficiencies were determined at the corresponding energies for three different geometries (source to detector distance of 1, 5 and 10 cm). The semi-empirical approach produced better and precise results that logically rhymed with theory than the traditional approach. Besides that, a consistency in the nature of the graphs and values were evidenced. The determined efficiencies and their corresponding energies revealed encouraging outcome and ensured the successful NAA for large samples of different material compositions

Natural radioactivity in major rivers of Kelantan state, Malaysia

Assessment of natural radionuclides (238U, 232Th, and 40K) and terrestrial gamma radiation dose rates (TGRD) in major rivers of Kelantan states, Malaysia were conducted. Measurements were carried out using a portable [NaI(TI)] micro roentgen (μR) survey meter and inductively coupled plasma mass spectrometer (ICP-MS) for in situ TGRD and the activity concentrations of 238U, 232Th, and 40K in water samples, respectively. The mean TGRD was found to be 312.98 nGy h-1 and from water samples analyzed, the mean activity concentrations of 238U, 232Th, and 40K was found to be 13.31 mBq L-1, 4.39 mBq L-1 and 1118.72 mBq L-1 which were about 3 times and slightly higher than the world average values of 5 mBq L-1 and 3 mBq L-1 respectively

Synthesis and Characterization of SnS: 3%Bi thin Films for Photovoltaic Applications

    Abstract In the present article, Nano crystalline SnS and SnS:3% Bi thin films were fabricated using thermal evaporation with 400±20 nm thickness at room temperature  at a rate deposition rate of 0.5 ±0.01nm /sec then annealing for one hour at 573 K for photovoltaic application. The prepared samples were characterized in order to investigate the structural, electrical, morphological, and optical properties using diverse techniques. XRD and SEM were recorded to investigate the effect of doping and annealing on structural and morphological possessions, respectively. XRD showed an SnS phase with polycrystalline and appeared to form an orthorhombic structure, with the distinguish trend along the (111) grade, varying crystallite size from (19.45-25.95) nm after doping and annealing. SEM investigations of these films show extremely fine nanostructures and demonstrated excellent adhesion, after Bi-doping, the nanostructures remained identical with a little change. UV/Visible studies were made in the range of wavelength (300-1100) nm to calculate the optical constants for these films. These measurements revealed a high value of the absorption coefficient and decrease the optical energy gap values ​​from (1.85 -1.6) eV after doping with 3% Bi. The characterization of these films it can be chosen in the application of solar cells. On the other hand, the optical properties of SnS films have been enhanced by Bi-doping

Assessment of potential human health and environmental impacts of a nuclear power plant (NPP) based on atmospheric dispersion modeling

The United States Environmental Protection Agency (US-EPA) short-range atmospheric dispersion model (AERMOD, v. 12345) is a good candidate for the calculation of offsite radiation doses to the general public, and its advanced capability should provide better confidence in the accuracy of offsite public doses assessment. In this paper the AERMOD code has been used to assess the impact of routine and accidental atmospheric radioactive discharges from a new nuclear power plant (NPP) site in Geregu, Nigeria (7° 33’ N, 6° 41’ E) on the four major settlements (Ajakuta, Lokoja, Idah and Okene) that lay within the emergency planning zones of the NPP. The code has produced values of the scaling factors for ground level air concentrations and depositions of radionuclides (from the passing plume) over our areas of interest. The scaling factors have been used to assess the potential radiological impact on the offsite human and non-human biota. While the radiological impacts on humans were calculated using the popular computation methods set by regulatory authorities, an integrated approach to the assessment and management of environmental risks from ionizing radiation (D-ERICA) was adopted for the non-human biota. The results of this work indicate that, under normal operations, the NPP does not pose any significant public health and environmental impacts. However, accidental conditions characterized by precipitation will lead to discernible radiological risks within the NPP sites emergency planning zone

First nuclear power in Nigeria: an attempt to address the energy crisis?

This paper attempts to explore to what extent a first Nuclear Power Plant (NPP) will improve the energy situation in Nigeria and investigates the socio-economic impacts of the NPP on the communities where the facilities are to be sited. Other issues that are addressed in this paper include the policy issues, lack of investments in power infrastructure and the security threat owing to incessant domestic militancy or terrorism. The paper then outlines the ways to tackle these problems and concludes that despite the facts that the addition of nuclear power into Nigeria's energy mix will help in curtailing the country's energy crisis, it also poses some challenges to the country that the policy and decision-makers must take into consideration right from the preliminary stages of the programme