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The gas chromatography-mass spectrometry technique was used to investigate the composition of the reaction products of unsymmetrical dimethylhydrazine with a potassium permanganate and potassium permanganate-hydrogen peroxide mixture. If the water contamination level is within 50 threshold limit values (TLV) (1 mg/ml), the proposed detoxication method utilizing potassium permanganate in combination with hydrogen peroxide allows for the reduction of the UDMH concentration to a safe level without the accumulation of transformation products. The detoxication of aqueous solutions with significant UDMH concentrations (up to 50000 TLV) (1 g/l) with potassium permanganate alone or in combination with hydrogen peroxide reduces the UDMH concentration to a safe level, but UDMH transformation products, including the extremely toxic nitrozodimethylamine, are accumulated in the solution. [ABSTRACT FROM AUTHOR]

In September 2000, July 2001, and August 2002, three marine expeditions onboard the R/V Ekolog were carried out to study physical, chemical, geological, and biological processes in two estuaries of Karelian coast of the White Sea. A wide complex of modern methods of marine field work was used. The most recent biochemical studies on the estimation of mechanisms of adaptive reactions of hydrobionts to environmental factors (including anthropogenic) were used. [ABSTRACT FROM AUTHOR]

The capacity for biopolymer transformation involving efficient and highly specific natural enzyme mechanisms was studied in seawater of the dynamic zone of the Norwegian Sea (the Voring Plateau region). Vertical and spatial variation in proteinase and amylase activities was demonstrated in seawater and the potential rates of degradation of specific substrates, azocasein and Procion-5CX-modified starch, were calculated. High proteolytic activity was demonstrated for the upper photic layer (0–10 m) in the southwestern part of the polygon (up to 88 U/l; vpr = 7.04 mg/l/h). Proteolytic activity in the bathyal layer (1500 m and below) sharply decreased to 8–16 U/l; vpr = 0.64–1.28 mg/l/h. Similar to other regions of the ocean, the pattern of amylase activity in seawater included low rates of polysaccharide destruction (0–4 U/l; vst = 0–0.2 mg/l/h) in water with high proteolytic capacity and, conversely, the top amylase activity (up to 246–490 U/l; vst 12.3–24.5 mg/l/h) in seawater layers with undetectable or low proteolytic activity. The spatial distribution of the enzyme activities can indicate the presence of waters of different origin. In the southwestern part of the polygon, statistical analysis demonstrated high correlations between hydrophysical indices (temperature, salinity, and salinity gradient) and proteinase and amylase activities. The ecological evaluation based on express enzyme-substrate tests demonstrated a stressful situation for destruction of proteins in both the photic layer and the layers below 1000 m ( tpr ≥ 10 h). [ABSTRACT FROM AUTHOR]

The article discusses the study focusing on the important consequences resulting from the photonic crystals (PCs) surface existence. Accordingly, the mechanism for the formation of the Bragg diffraction of light spectra was analyzed. The result showed that, among others, Bragg diffraction of light on an inclined plane results to a strong alteration of electronic field in which new states emerged in the photonic bandgap.