20 research outputs found

    Divalent Cu, Cd, and Pb Biosorption in Mixed Solvents

    Get PDF
    Dead dried Chlorella vulgaris was studied in terms of its performance in binding divalent copper, cadmium, and lead ions from their aqueous or 50% v/v methanol, ethanol, and acetone solutions. The percentage uptake of cadmium ions exhibited a general decrease with decrease in dielectric constant values, while that of copper and lead ions showed a general decrease with increase in donor numbers. Uptake percentage becomes less sensitive to solvent properties the larger the atomic radius of the biosorbed ion, and uptake of copper was the most affected. FT-IR analyses revealed stability of the biomass in mixed solvents and a shift in vibrations of amide(I) and (II), carboxylate, glucose ring, and metal oxygen upon metal binding in all media. ΔνCOO values (59–69 cm−1) confirmed bidentate metal coordination to carboxylate ligands. The value of νasCOO increased slightly upon Cu, Cd, and Pb biosorption from aqueous solutions indicating lowering of symmetry, while a general decrease was noticed in mixed solvents pointing to the opposite. M–O stretching frequencies increased unexpectedly with increase in atomic mass as a result of solvent effect on the nature of binding sites. Lowering polarity of the solvent permits variations in metal-alga bonds strengths; the smaller the metal ion, the more affected

    Web Application based Image Geolocation Analysis to Detect Human Trafficking

    Get PDF
    Migrant smuggling is a dangerous phenomenon threatening international peace and security. This global concern for many countries is mainly due to the high use of multimedia devices and social media. There are great demands to specify an in depth gathering of information about a suspect’s mobile device while investigating cases of human trafficking and migrant smuggling. The primary purpose of this study is to help resolve the human trafficking problem that currently faces Sudan. In this paper we cover the steps used to geolocate images captured from suspects and victims’ mobile devices cameras. The obtained images are then analyzed using our specialized developed web application. This latter is built using open-source tools such as the Laravel framework and a Google Maps API which is considered as the main component of the web application. The results of the developed web application on a real case in Sudan has proven its usefulness in easing and speeding up the digital investigation proces

    Synthesis, Characterization, Mössbauer Parameters, and Antitumor Activity of Fe(III) Curcumin Complex

    Get PDF
    Curcumin-Fe(III) complex was prepared from Fe(NO3)3·9H2O precursor and curcumin by refluxing a slightly basic methanolic solution of their mixture with the objective of investigating its cytotoxicity. The enol form of curcumin ligand was established by FTIR, UV/Vis, 1H NMR, and 13C NMR spectroscopy. The as-prepared product was characterized by elemental analysis, FTIR, UV, and Mössbauer spectroscopic techniques. An octahedral high-spin Fe(III) complex was obtained, δ, 0.37 mms−1; Q.S., 0.79 mms−1; no magnetic relaxation was observed at liquid N2 temperature, neither reduction of Fe(III). The tested cytotoxicity of the as-prepared complex on four cancer cell lines indicated inhibition of the curcumin activity upon complexing with iron

    Adsorpce mědi v půdě a její závislost na fyzikálních a chemických vlastnostech

    No full text
    Soil samples (n=11) were collected in the chernozem areas of the Czech Republic (the Central Europe) from the topsoil and used as representative samples. All sampling areas have been used for agricultural purposes (arable soil) and they were selected as typical representatives of agricultural soil. These samples represented the soil with same genesis (to reduction differencies between soil types) but with different soil properties (physical and chemical). Complete chemical and physical analyses were made for confirmation of copper adsorption on solid phase: we analysed the particle size distribution, content of oxidizable carbon (Cox), the cation exchange capacity (CEC), supply of exchange calcium, magnesium, sodium, phosphorus and potassium, soil reaction and the total supply of Fe, Al, Mn, Ca, Mg, K, P and N. The strongest simple correlation between analysed soil properties and copper concentration had content of available magnesium (r =0.44) and available phosphorus (r=MINUS SIGN 0.51). In the case of multiple correlations (i.e. collective influence of multiple soil properties) had the strongest influence combination of clay, soil reaction, total content of phosphorus, available magnesium and available phosphorus. The main influence of phosphorus and magnesium is evident. We suppose that copper and phosphorus enter into specific complex. Influence of these five soil properties can explain 92.7 % (r = 0.927) changes in the content of copper changes in the experiment.O
    corecore