The main aim of this study is to determine the changes occurred in the antioxidant capacity and UV-protection capacity of rutin with a different redox-potential metal cation. The complexes were characterized by UV-Visible and IR spectroscopy. Rutin belongs to the flavonols and it is a glycoside form of quercetin. Chelate formation is a result of interaction of rutin with metal ions. The chelation of metals can be crucial in the prevention of radical generation, which damages target biomolecules. The interactions between flavonoids and transition metal ions to form complexes that prevent the participation of metal ions in free radical generating processes, thus exhibit an anti-oxidant behavior, metal-flavonoid complexes various biological and pharmacological activities. The coordination of Rutin (Rut) with Rut-Zr, Rut-Mo, Rut-Zn, Rut-Cu, Rut-Ni, Rut-Fe, Cit-Zn, Cit-Mo, Cit-Zr, Cit-Cu, Cit-Fe, and Cit-Ni may simulate the catalyzed centre of the hyperoxide dismutase in the metal coordinate structure, thus displayed the DPPH, hydroxyl radical scavenging activity, metal chelating, and nitric oxide (NO) and superoxide dismutase (SOD) radical scavenging. Therefore, the metal flavonoid complexes are very helpful in discovery and development of new drugs.

The doubly hydrogen-bonded dimer of pyrrolidinone (γ-lactam) is used as a benchmark for the effect of conjugation on the strength and extent of hydrogen-bonding of the compounds Oxindole and Isoxindole. The experimental portion of this project consists of collecting the FTIR spectrum of γ-lactam, Oxindole and Isoxindole in CCl4. The concentrations and temperatures were varied to determine the thermodynamic properties of ΔHd, ΔSd and Kd. In addition, the spectroscopic parameters of the difference of the monomer and dimer N-H stretching frequencies (Δν) and the ratio of the molar extinction coefficients of the dimer and monomer (ed/em) are experimentally determined. The values of ΔHd, ΔSd, Δν and ed/em are computed using MP2 and B3LYP methods with 6-31G** and 6-31+G** basis sets. The experimental values are best described by B3LYP/6-31G**with the incorporation of the dielectric effect (PCM) of CCl4. The experimental and computational results support the results of increased or decreased hydrogen-bond strength due to conjugation effects on the polarization of the monomers in forming dimers.

Oxidation catalysis of organic substances has attracted special attention in recent years due to of their high industrial significance in green and energy chemistry. The implementation of a transition metal-based catalyst in combination with oxygen is an alternative to the traditional procedures. This study justifies the application of amperometric response 'in situ' for estimation of the electrocatalytic activity of metal oxide films, which are known to be promising for oxygen transfer processes. The reaction of electrooxidation of Mn2+ ions may be termed as a 'marker' for oxygen transfer reactions due to its kinetic features, such as proportionality between the current density and the surface concentration of •OH-radicals. The relative parameter, kox, has been offered for estimation of the oxidizing capacity of an anode material toward oxygen transfer reaction in reference to platinum oxidizing capacity. kox value is automatically calculated exactly during electroplating of MnOx as a ratio of the current density of Mn2+ + 2H2O – 2e→MnO2+4H+ reaction on the tested surface to the current density of this reaction on Pt surface. The developed method was tested during the investigation of catalytic activity of MnOx films for electrooxidation of glucose. The parameter kox was calculated for other anode materials and was analyzed. The application of the new method allows estimating and comparing the catalytic performance toward oxygen transfer reactions of anode materials or of the same material in different modifications, such as nano particles, composites, different compositions etc. The pre-test reduces manifold the time spent for determination of oxidizing capacity of oxides.

Air pollution is a problem in both developed and developing countries. As a corrective measure, constant air monitoring is usually performed by conventional techniques which are costly and time consuming hence the need for cheaper methods. Recently, biomonitoring has emerged as an effective alternative method. The aim of this study was to investigate heavy metal air pollution in the environment using Mosses. Mosses are lower plants that can provide a surrogate and time-integrated means of measuring elemental depositions from the atmosphere to terrestrial systems. Atmospheric deposition of heavy metals Chromium (Cr), Copper (Cu), lead (Pb), and Zinc (Zn) was studied at the University of Zimbabwe. Moss samples were hung on sites selected by a systematic grid sampling method, during the summer of 2016. The concentrations of heavy metals were determined by Atomic Absorption Spectroscopy (AAS). The concentrations were expressed as Relative Accumulation Factors (RAFs) and the means for Cr, Cu, Pb and Zn were 14.38; 18.17; 9.63 and 10.78 respectively. The results showed the concentration order of deposition was Cu > Cr > Zn >Pb and that Zn deposited uniformly as evidenced by its low sample variance which was more than 17 and 56 times smaller than that of Pb and Cr-Cu respectively. Although the distribution patterns of Cr and Cu were similar, Pb and Zn had their own patterns. The results suggested that the source of heavy metal could be from traffic related air pollutants.

This study was carried out to assess the levels of the metabolites of Aspergillus flavus; aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), and aflatoxin G2 (AFG2) in various food samples. Corn (24.00 µg/kg), millet (4.13 µg/kg), and cassava (3.88 µg/kg) contained the highest AFB1, while AFB2, AFG1, and AFG2 occurred highest in corn and yam. After processing, cassava and yam recorded the highest percentage of AFB1 and AFB2 reduction respectively, while the decontamination of AFG1 was jointly most effective after wheat and millet processing, and AFG2 reduced most after wheat, cassava, and millet processing. The occurrence of AFB1 in the legumes, followed the order; beans > breadfruit > groundnut > melon > oil bean and for AFB2 and AFG2 levels, breadfruit > melon > oil beans > beans, while AFG1 occurred highest in breadfruit, groundnut and oil beans. Ugba (6.26 µg/kg), Ogiri (10 µg/kg), and beans flour (14.62 µg/kg) had the least total aflatoxin contents of the legumes evaluated. Egusi, beans and oil bean recorded over 80% AFB1 and AFG1 reduction, while processing of groundnut and breadfruit, and breadfruit and melon produced the highest percentage of AFB2 and AFG2 respectively. The result for the vegetables showed least contamination of AFB1 in nchuanwu and bitter leaf, while the occurrence of AFB2, AFG1, and AFG2 in nchuanwu and bitter leaf occurred below detection levels. Blanched nchuanwu and bitter leaves had 100% AFB1 reduction, while the percentage reductions of AFB2 in oha and curry leaves, AFG1 in oha, and AFG2 in pumpkin leaves were 100%. This study has shown the presence of aflatoxins in the foods beyond permissible limits, as well as the effectiveness of milling, fermentation and blanching in reducing aflatoxins from carbohydrate rich foods, proteins, and vegetables respectively.

The molecular modeling, geometry optimization and characterization of bimetallic complexes derived from 4, 8-dimethyl-2, 6-diphenyl-1, 5-dihydro-s-indacene has been performed using semi empirical method. The three bimetallic complexes containing transition metals Fe, Ni and Fe-Ni were investigated. Namely, (Cp*Fe)2Ic', (Cp*Ni)2Ic', (Cp*Fe)Ic'(Cp*Ni). (Where Cp*=Pentamethyl-ƞ5-cyclopentadienyl, Ic'=2, 6 diphenyl-4, 8-dimethyl-s- Indacene.) In these study geometrical parameters, vibrational frequencies, dipole moment and total energies were calculated by PM6, parametric method. The theoretical electronic (UV-Vis) spectrum calculated using TD-SCF (RPM6) in gas phase. The frontier orbital analyses measure the values of HOMO, LUMO energies and their energy gap. The calculated HOMO-LUMO energy gap show that charge transfer occurs within the molecule.

Mycotoxins are toxins produced by aspergillus, a type of fungus that can be found virtually everywhere and their toxicity occurs at very low concentrations. For good storage condition of the post-harvest grains, the sensitive and reliable methods for detecting mycotoxins are required for long-term sustainability of animals ingesting excessive amounts of the toxin from chronic health problem to death. The aspergillus grows rapidly in the air with high relative humidity contrast to the air with low relative humidity. In this study, the samples of maize were randomly collected in three sectors: Nyamata, Gakenke and Mahembe. Using selective media and biochemical tests, the three strains; A. flavus, capable of producing both B- and G-type aflatoxin and A. pseudotamarii which has not previously detected in our region and A. parasiticus, isolated from the collected maize and the total aflatoxin (AFT) in maize flour was evaluated by Reveal Q+; the mean concentrations of AFT were 52.3±3.93 CFU/ml for Mahembe sector, 49.5±0.98 CFU/ml for Gakenke sector and 43.7±2.15 CFU/ml for Nyamata sector. The level of AFT contamination in a, b, c sectors was higher than the maximum tolerable limit of aflatoxins recommended by the United States Food and Drug Administration guidelines for aflatoxin in animal feeds and human foods at 20 parts per billion (20 ppb).

An innovative protocol to the synthesis of this material emerged on exploring the potential of the various form of N-aminophthalimides on its reaction with a number of aromatic aldehydes. New series of biologically active substituted Schiff bases with general formula, R1N=CHR2 where R1 = 3-nitro-N-aminophthalimide, 3-bromo-N-aminophthalimide, 4-nitro-N-aminophthalimide, 4-bromo-N-aminophthalimide, R2 =2, 6-dichlorobenzaldehyde, o-anisaldehyde and o-vanillin were synthesized by the reaction of substituted N-aminophthalimides and substituted aldehydes in ethanol. Moreover N-aminophthalimides (50-70% yield) were synthesized by reactions of corresponding phthalimides and hydrazine hydrate. Such compounds were characterized by different physico-chemical techniques like, melting point, elemental analysis, multinuclear NMR (1H, 13C).The synthesized compounds were screened for antibacterial and antifungal activities. The explorations of the biological properties of the compounds are mentioned in this paper.

There is a concern among professionals and teachers of scientific and technological Degrees for the lack of vocations for this type of study. In order to mitigate this problem to some extent, Technical University of Madrid (UPM) and some Educational Innovation Groups, formed by Chemistry teachers, have been worked for some years on the organization of several activities to promote the relation among different educational levels, mainly early High School and University. On the other hand, different teaching materials have been developed in order to encourage the motivation and ease the learning of the basic subjects of the first-year of university studies by the students of UPM, with tools or resources such as Punto de Inicio, OpenCourseWare (OCW), Puesta a Punto, at an institutional level. Furthermore, some Educational Innovation Groups have created audiovisual materials (lab practice videos) and virtual lab practices for the learning of Chemistry, as well as games such as Math-Trivial, Physic-Trivial, Drawing-Trivial and Chemical-Trivial. These tools are available on the Internet, as free access web spaces.

The Brazilian repository is being planned to be a near-surface one. In Brazil the low and intermediate level radioactive wastes are immobilized using cement and bitumen for Angra 1 and Angra 2 NPP, respectively. The major problems due to the disposal of bituminized wastes in repositories are swelling of the waste products and their degradation in the long term. To accommodate the swelling of the bituminized wastes, the drums are filled up to 70 - 90% of their volume, which reduces the structural repository stability and the disposal availability. Countries, which use bitumen in the solidification of NPP's radioactive waste and have near-surface repositories, need to immobilize this bituminized waste within other drums containing cement pastes or mortars to dispose them. This study aims to evaluate the properties of cement pastes and mortars to be used in the encapsulation of bituminized wastes. The formulations of two pastes and two mortars were selected for the pilot scale tests. The laboratory and pilot scales results were very similar, indicating that any of these formulations could be used. However the better formulation will be chosen after the leaching test results, because it is an essential parameter in the long-term repository performance.