A novel stitched transmission line for wearable devices has been manufactured and tested to measure its scattering parameters from 0.04 to 4 GHz. The stitched transmission line which is 150 mm long consists of an inner conductor surrounded by a tubular insulating layer. For shielding purpose, the structure is stitched onto a denim material with a conductive thread with the aid of a novel manufacturing technique using a standard hardware. The S-Parameters were investigated with three different stitch angles 85 ; 65 ; and 31 through simulation and experiments, demonstrating that the stitched transmission line can work usefully and consistently from 0.04 to 4 GHz.

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Twelve samples of water from hand-dug wells in some parts of Kaduna South and its Environs were selected using a stratified random sampling. Twenty (20mils) of concentrated nitric acid were added to each two liters of the sampled water for preservation. The samples were then evaporated and counted for Gross Alpha activity using MPC-2000-DP model gas free proportional counter at Centre for Energy Research and Training (CERT), Ahmadu Bello University, Zaria.  Results show that, the range of alpha activity in water in the area was 0.001 to 0.413 Bq/L, with geometric mean of 0.124±0.040 Bq/L. The overall results show that, the alpha activity have their values below WHO recommended practical screening level of 0.5 Bq/L radioactivity for drinking water.

In this study, carbon nanotubes (CNTs) were synthesized directly on coated silicon substrate via commercial microwave oven at 2.45 GHzf for3 minutes (Sample A) and 4 minutes (Sample B). The plasma provides the required temperature for catalytic decomposition of carbon source (polyethylene) at 750 ?C under atmospheric pressure. Raman spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), High Resolution Transmission Electron Microscope (HRTEM), X-ray diffractometer (XRD) techniques are used to characterize the as-synthesized. Results indicate that, the calculated carbon quality was found to be 1.01 and 1.02 for sample A and sample B respectively with average diameter range of (6.0 to 10.0) ± 0.5 nm. The high intensity ratio is attributed to the defect mode in the CNTs. Also, the analysis from FESEM shows twisted and randomly oriented structures with an interlayer spacing of about 0.35 nm in the internal structure of most CNTs. HRTEM further confirmed the interlayer spacing of about 0.35 nm corresponding to FESEM result. The crystallinity of the CNTs was obtained via X-ray diffraction techniques. Lastly, the results indicate sample A and B produces CNTs, with sample B having more graphitic structure than sample A due to duration of synthesis process.

Groundwater (well and borehole) and surface water samples from various locations of Idah and environs including  have been investigated for their 222Rn concentrations by Liquid Scintillation Counter (Packard Tri-Carb LSA 1000TR)  manufactured by Packard Instrument Company. The mean concentration ranges from 4.70 Bq/L to 24.0 Bq/L for borehole samples, 5.70 Bq/L to 13.60 Bq/L and 1.90 Bq/L to 4.50 Bq/L for well and surface water respectively were found. The average mean concentration of 10.23 Bq/L and 12.28 Bq/L were found for borehole and well waters respectively which were above the maximum contaminant limit of 11.1 Bq/L set by USEPA and 10.0 Bq/L by UNSCEAR and WHO. The average mean concentration of 3.05 Bq/L was found for surface water making it safe drinking and domestic use. The average total effective dose by ingestion was found to be 0.0412mSv/y which is lower than the recommended limit for members of the public of 1.0 mSv/y and intervention level of 3 – 10 mSv/y by ICRP.