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Uncontrolled exploitation and degradation in the environment over the past few decades as the result of urbanization and poverty has caused a serious damage to lives and properties. The study analysed the spatial distribution of heavy metal (Fe, Cu and Zn) in Bagega, Zamfara state. Three mapping units were identified and samples were collected from the top soil (0-15cm) horizon using stratified random sampling techniques. These include the Mining Processing Environment (MPE), Residential exterior (RE) and Surrounding Farmlands (SF). In each mapping units, twelve (12) samples were collected randomly. Coordinates of all samples points were recorded using GPS. The soil sample were analyse for heavy metals using Atomic Absorption Spectrophotometer (AAS) and the result were recorded in Microsoft excel and later transformed into GIS environment in the Arc GIS 10.1 version. Krigging model was used for mapping the spatial distribution of the heavy metals in the study area. The result shows that there are more concentrations of heavy metals (Fe and Cu) in the Residential exterior (RE) and streams sites. The level of heavy metal in the soils of the area were below the acceptable toxic level of and this can be attributed to the number of years quarry activities in the study area have been in operation. The study concluded that Fe and Zn are more concentrated to the mining and river sites areas, while Cu is highly concentrated at the farmlands areas. The study recommends for continuous monitoring and mining should be avoided especially closer to the residential areas.

Food packaging is often made from plastic, which is usually obtained from non-renewable resources. The development of new technologies, like biocomposite films, has been driven in response to environmental concerns as well as consumer demands for eco-friendly, high-quality products derived from nature. Biocomposite films were prepared by incorporating taro mucilage, carboxymethyl cellulose (CMC), ZnO, glycerol, and black cumin seed (BCS) oil. The SEM results showed that the biocomposite films containing taro mucilage (TM), ZnO, and BCS oil had noticeably smoother surfaces. The FTIR analysis indicated the existence of a -OH group, N-H bond, alkaline group, C-C, C=N, C-H, C-O-H, and C-O-C bond formation, confirming the interaction of CMC, glycerol, BCS oil, ZnO nanoparticles, and TM. The results of TGA and DSC analysis suggest that incorporating ZnO nanoparticles, BCS oil, and TM into the CMC polymer matrix increased thermal stability. The addition of TM significantly increased water uptake capacity, antioxidative property, tensile strength, and elongation at break, with significantly decreased whiteness index and water solubility. The film inhibited the growth of Staphylococcus aureus and Escherichia coli as foodborne pathogens. The results suggest that the films can be potentially used as environment-friendly antioxidative and antimicrobial packaging films with additional research.

Herein, we have investigated the interaction of bovine serum albumin with a cetyldimethylethylammonium bromide, via a conductivity and molecular dynamics methods in the absence/presence of electrolyte solutions.

As we approach the 125 th anniversary of the Michelson-Morley experiment in 2012, we review experiments that test the isotropy of the speed of light. Previous measurements are categorized into one-way (single-trip) and two-way (round-trip averaged or over closed paths) approaches and the level of experimental verification that these experiments provide is discussed. The isotropy of the speed of light is one of the postulates of the Special Theory of Relativity (STR) and, consequently, this phenomenon has been subject to considerable experimental scrutiny. Here, we tabulate significant experiments performed since 1881 and attempt to indicate a direction for future investigation. Keywords: Isotropy test, Special theory of relativity, Constancy of the one-way speed of light.

Development of a controlled atmosphere (CA) plant and shelf-life of fresh tomatoes at different storage conditions were studied in this research. The controlled chamber (4.5' × 4.5' × 4.5') with supplement of 1% L-ascorbic acid as antioxidant source was constructed using locally available materials. Fresh tomatoes were kept with wrapping by low density polyethylene under refrigerated and CA storage conditions. The maximum shelf-life of fresh tomato was 42 days under CA condition and followed by 35 days in refrigeration condition. Though initial cost of controlled atmosphere was high but it resulted in maximum shelf life of tomato. However, CA condition retained the physiological changes namely, color change, TSS, and weight loss of fresh tomatoes than that of stored in refrigerated condition. From nutritional point of view, it was concluded that developed CA plant could be used to extend the shelf-life of fresh tomatoes with minimum physicochemical changes throughout the storage period.

Herein, the conductivity measurement technique is used to determine the interactions that may occur between polyvinyl pyrrolidone (PVP) polymer and cetylpyridinium chloride (CPC) surfactant in the presence of NaCl and Na2SO4 of fixed concentration at variable temperatures (298.15–323.15 K) with an interval of 5 K. In the absence or presence of salts, we observed three critical micelle concentrations (CMC) for the CPC + PVP mixture. In all situations, CMC1 values of CPC + PVP system were found to be higher in water than in attendance of salts (NaCl and Na2SO4). Temperature and additives have the tendency to affect counterion binding values. Various physico-chemical parameters were analyzed and demonstrated smoothly, including free energy (ΔG0m), enthalpy (ΔH0m) and entropy change (ΔS0m). The micellization process is achieved to be spontaneous based on the obtained negative ΔG0m values. The linearity of the ΔHmo and ΔSmo values is excellent. The intrinsic enthalpy gain (ΔH0*m) and compensation temperature (Tc) were calculated and discussed with logical points. Interactions of polymer hydrophobic chains or the polymer + surfactant associated with amphiphilic surface-active drugs can employ a strong impact on the behavior of the gels.

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