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This study is focused on the evaluation of the geophagic characteristics of the sedimentary clay deposits at Share and Tshonga areas, northern Bida Basin, Nigeria. The methods used include particle size distribution, cation exchange capacity (CEC), acidity and alkalinity (pH), X-ray diffractometry, and bulk inorganic geochemical analysis (X-ray fluorescence and inductively coupled plasma mass spectrophotometer). The investigated clays are classified as dominantly clayey–silt with minor clayey–sand type, which conforms with the textural standard of geophagic clays obtained from different parts of the world. The whitish coloration of the clays with an occasional red stain also compares well with geophagic clays from Kenya and parts of South Africa and is therefore considered suitable for consumption. The observed low CEC (1.71–5.06 cmol(+)/kg) and acidic pH (4.54–6.87) values of the clay samples would make them effective against nausea and excessive salivation during pregnancy. The mineralogical compositions of these clay samples show the dominance of kaolinite with minor non-clay minerals, which makes it suitable not only for food detoxification but also as an alleviation of gastrointestinal disorders such as diarrhea. Chemical analysis shows a low percentage per weight of certain elements that are of nutritional value, though not in the present state but better as excipients in the pharmaceutical industry. It was observed, however, that consumption of more of the studied clay may lead to adverse health due to the presence of some heavy metals (Co, Cu, Ni, Cd, Ag, and Pb) with concentrations in excess of the permissible limit.

Electrospinning has emerged as one of the major technologies for designing and fabricating tissue engineering membranes. The resemblance of the electrospun fiber structure to blood capillaries endowed them with unique capabilities to mimic the native tissue biological characteristics, while the high surface‐to‐volume ratio enables them to exert a controlled release of drug directly to the exposed interstitial tissue. This research attempts to compare the characteristics of different electrospun polyvinyl alcohol/hyaluronic acid (PVA/HA) composite material nanofibrous membranes in order to identify the optimal material‐fabrication combination for wound dressing and skin tissue engineering applications. Far‐field electrospinning equipped with both rotatory and wire collectors is considered for membrane fabrication. PVA with different concentrations and molecular weights of HA are electrospun as nanofibrous membranes considering a voltage of 30 kV on both types of collectors. Comprehensive characterization is conducted including morphological, chemical, thermal, mechanical, and in vitro mucoadhesion analysis. In vitro cell viability/proliferation studies are also carried out and pointed out that the designed membranes are cytocompatible, and able to support keratinocytes proliferation. All these results proved that the fabricated PVA/HA nanofibrous membranes are suitable for wound dressing and skin tissue engineering applications, the optimal material‐fabrication combination is also determined. [ABSTRACT FROM AUTHOR]

Groundwater quality of Iworoko-Ekiti and environs for irrigation and domestic purposes has partly been established using chemical indices. Groundwater quality assessment in the area is of great importance because of the influence of various activities in the area. The area is thickly populated by citizens and higher institution students across Nigeria. At the moment, sanitary conditions are very poor as the main occupations are trading and farming. Nineteen hand-dug wells were randomly sampled within the settlement. Flame photometry and spectrometry were used for cations and anions analyses respectively. Average values of pH, EC and TDS are 7.02, 342µS/cm and 230ppm. The average trend of major cations and anions concentrations is Ca2+>Na+>Mg2+>K+ and HCO3->Cl->SO4²->CO32- respectively. Average values of Degree of Contamination and Revelle Index are 14 and 0.6 respectively. SAR, MAR, %Na, KI, TH, CIA-1 and CIA-2 has an average value of 0.7, 37.4, 24.8, 0.3, 162ppm, 0.4 and 0.9 respectively. Based on these values, the water is suitable for irrigation. In general, 31.6% of the hand-dug wells are slightly acidic and 10.5% have Revelle index >1 above recommended values respectively. 10.5% from the hand-dug wells have KI above one, 5.3% has MAR above recommendation making them unfit for irrigation purposes. Hence, majority of the wells are suitable for irrigation with exception of a few wells. However, the elevated Cl- concentrations in all the wells, make them unfit for human consumption. Weathering of migmatite and granite gneisses together with anthropogenic activities really contributed to the chemistry of the groundwater. [ABSTRACT FROM AUTHOR]

The interbedded coals and shales facies of the Gombe Formation were subjected to organic petrology and source rock kinetics for evaluation of thermal maturity, kerogen type and the hydrocarbon generation from the kerogen. The distribution and kinetic parameters obtained through kerogen cracking was generated by processing the data obtained from Rock eval 6 pyrolysis using ORFA (One Run Fixed A) software. The activation energy distributions observed in the samples are broad (41-65 kcal/mol) with associated fixed frequency factors of 2.00E+14/s indicating heterogeneous compositions and bond types typical of Type III kerogen (HI = 57-172 mgHC/gTOC). The peak hydrocarbon bond breaking is between 54 and 55 kcal/mol for the organofacies defining up to 70% of the petroleum potential while the main phase and peak of hydrocarbon generation is between 460 - 465oC for the organofacies at constant heating rate of 25oC/min. Petrographic examinations revealed that organic matter in the organofacies consists of opaque to non-opaque biostructured phytoclasts, cuticles and some common spores and pollen. Vitrinitic maceral was abundant in the samples indicating gas prone organic debris. Palynofacies revealed the presence of trilete spore and pollen well preserved in the samples and showed good fluorescence. The Thermal Alteration Index (TAI) ranges from 2.4-2.6 suggesting late diagenetic stage for the organic matter maturation. It is concluded that the samples are thermally immature and constitute moderate to good quantity of organic matter with potential to generate mainly gaseous hydrocarbon. [ABSTRACT FROM AUTHOR]