Ground water samples from residential homes in three Regions of Ghana: Central, Greater Accra and Ashanti, were analyzed for iron and manganese contamination. The samples were exposed to characterized zeolite Y by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transformed-infrared spectroscopy and thermos gravimetric-differential thermal analysis. Zeolite Y is able to remove 98% of iron and 97% of manganese within an hour. The adsorption of both iron and manganese followed the Freundlich model, suggesting that the ions were transported onto the zeolite Y surface and subsequently diffused into the zeolite Y framework. The kinetic studies showed that pseudo-first order and intra particle and film diffusion models provided the best fit. The adsorption at 0.2 mg L −1 Fe (Q 0.2 ) is calculated to be 0.023 mg g −1 for the Freundlich adsorption model, whilst that of manganese at 0.05 mg L −1 Mn (Q 0.05 ) is evaluated to be 0.015 mg g −1 . The zeolite retains its adsorption properties when retrieved from the first exposure water sample, washed copiously with distilled water and added to fresh water samples. The results suggest that zeolite Y can be used as a potential adsorbent for the removal of iron and manganese from groundwater.

Zeolite types LTZ and LSX were synthesized from bauxite and kaolin in Ghana and characterized by x-ray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy and Fouries transformed infrared spectroscopy. The zeolites were then applied to used lubricant oil and parameters lubricant engine oil were measured and compared to those of fresh ones. Parameters such as flashpoint, viscosity index, pour point, sulfur content, heavy metals, specific gravity, refractive index and carbon residue were analyzed. The results obtained showed that zeolite types A and X successfully removed heavy metals, particularly lead, copper and iron that were in the spent oil. A removal efficiency of 23.40 % Fe, 96.76 % Zn, 19.05 % Cu and 12 % Cr were obtained for Zeolite A with a yield of 62 % whilst 32.81 % Fe, 39.00 %, Zn, 47.61 %, Cu and 24 % Cr were obtained for zeolite LSX with a yield of 67 %. The viscosity index of the virgin, zeolite LTA treated and zeolite LSX treated oils were 115, 121 and 115 respectively. These results showed that used engine oils recovered using glacial acetic acid and zeolites A and LSX can be reused.

Elevated exposure to Ultra-Violet Radiation (UVR) from the sun has led to adverse effects on human skin and foods, and therefore, the need for materials that offer resistance to Ultra-Violet (UV) penetration for protection. Some building window and non-window-materials, car-glasses, Linear Low Density Polyethylene (LLDPE) and Polyethylene Terephthalate (PET) rubber and plastic materials have been investigated to determine their transparencies and suitability for use as shields against UVR. These were studied by directly measuring scattered solar radiation through the optical window of a spectrometer and then measuring the scattered light when the window was completely covered with the material to be examined. Wavelengths of light that were not absorbed when sunlight was incident on the samples and the transmitted intensity of sunlight at each wavelength through each sample as compared to the transmitted intensity through air were determined in the UVB and UVA spectral regions. The results showed that the building window-glasses were opaque to UVB but transparent to UVA while the non-window-glasses exhibited transparency in the UVB and UVA spectral regions. The car-glass (laminated), used as windscreen, was opaque to UVB and UVA while the side-glass (non-laminated) was opaque to UVB but transparent to UVA. Perspex, sometimes used as an alternative to windscreen and side-glass in cars, exhibited transparency in UVB and UVA spectral regions. The LLDPE materials used for food storage were transparent to UVB and UVA while the PET plastic materials used for water, fruit juice and beverage storage was opaque to UVB but transparent to UVA.

This study investigated the pore characterization of polyurethane (PU) foam as a necessary step in water filtration membrane fabrication. Porous material characterization is essential for predicting membrane performance, strength, durability, surface feel, and to understand the transport mechanisms using modeling and simulations. Most existing pore characterization techniques are relatively costly, time-consuming, subjective, and have cumbersome sample preparations. This study focused on using three relatively inexpensive imaging systems: a black box, Canon camera (EOS760D), and LaserJet scanner (M1132 MFP). Two standard, state-of-the-art imaging systems were used for comparison: a stereomicroscope and a scanning electron microscope. Digital images produced by the imaging systems were used with a MATLAB algorithm to determine the surface porosity, pore area, and shape factor of the polyurethane foam in an efficient manner. The results obtained established the compatibility of the image analysis algorithm with the imaging systems. The black box results were found to be more comparable to both the stereomicroscope and SEM systems than those of the Canon camera and scanner imaging systems. Indeed, the current research effort demonstrates the possibility of substrate characterization with inexpensive imaging systems.

Generation and propagation of ultrasonic waves in single layer Graphene Nanoribbon is studied using semi-classical approach. When piezoelectric Graphene Nanoribbon (GNR) is exposed to time varying light beam, ultrasonic waves are produced which propagate in the medium. At low frequencies, we observed oscillations of the ultrasonic observables, velocity change and attenuation which are characteristics of massless Dirac fermions in graphene. Exploiting this oscillatory behavior, we estimate graphene's electronic mobility to be around 5 2 10 cm V s . Propagating ultrasonic waves can be amplified, depending on the electric field amplitude. Specifically, amplification occurs when drift velocity exceeds sound velocity. This scheme can be employed for efficient ultrasonic amplifier device operation.