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Bucharest, Romania

Vasilache V.,Stefan Cel Mare University of Suceava | Cretu M.-A.,Al. I. Cuza University | Pascu L.F.,INCD ECOIND | Risca M.,Stefan Cel Mare University of Suceava | And 4 more authors.
International Journal of Conservation Science | Year: 2015

To study the pollution level in water of Suceava river, the dehydrogenases activity of the sediments has been evaluated. Samples have been gathered from three sites, Brodina, Mihoveni and Tisauti. There had been determining the actual dehydrogenases activity and potential one respectively, and on the other side the activity of malat-, a-cetoglutarate-, succinate-, and isocitrate-dehydrogenases respectively, enzymes implied in Krebs cycle of oxidative degradation. Dehydrogenases are components of the enzyme systems of microorganisms, playing an important role in the energy production of organisms. Their role is to oxidize organic compounds through the transfer of two hydrogen atoms. Due to this dehydrogenase activity can be used as an indicator of biological redox systems and also as measure of microbial activity in soil.

Uruioc S.,West University of Timisoara | Masu S.,INCD ECOIND | Sinitean A.,West University of Timisoara | Albulescu M.,Advanced Environmental Research Laboratory
Carpathian Journal of Earth and Environmental Sciences | Year: 2012

An assessment of the natural manifestations of fluids (gases, water) and solid phases (fine-grained sediments) from deep sediment layers of Banat area, in mud volcanoes (MVs) category is given. The total occurrence area of recent or ancient mud volcanoes in Fibiş Valley is about 0.9 km2. All the craters occur along the Fibiş Valley, along a NNE-SSW direction, at an average altitude of 121m. They occur along an active fault system, acting as conduits for the migration of fluids. The main crater is Forocici Crater (FC), where the gas emissions include CO2, CH4, CO and H2S. Seven secondary craters are recorded, and two are temporarily active, having several seepages with gas and water eruptions. Fluid flows of mud volcanoes of the Fibiş Valley have an important impact on atmospheric gas budget. The craters shape is generally irregular developing at soil level, with the exception of crater C2 (sub-circular shape) and Forocici Crater which has a gryphon type cone. Fe dominates the water samples collected at FC pool. Low concentrations of Cr, Ni and Zn were observed. Analyses of heavy metal concentrations of soil show wide variations. All concentrations of metal are low and below the maximum allowable limit. However, some samples show high concentrations of metals, such as those containing Fe, Pb and Cu. All examined soil and mud samples present a higher content of Fe (2144 mg/kg-2585 mg/kg). Generally, heavy metal concentrations in soil do not exceed the allowable maximum values, except Pb (27.5-38.0 mg/kg d.s.), toxic for animals grazing growing in Fabiş Valley. Salix cinerea L. which grows on the soil at the limit between the crater and Forocici Crater cone contains Fe (55.50-80.00 mg/kg d.s.), Cu (2.74-4.50 mg/kg d.s), Ni (0.15 mg/kg d.s), Pb (1.35 mg/kg d.s) and Zn (42.20 mg/kg d.s). The mineralized fluids brought from deep layers control heavy metals concentration. From the substratum of Forocici Crater, we identified six species of diatoms (Gomphonema minutum (Agardh) Agardh, Pinnularia obscura Krasske, Geissleria acceptata (Hustedt) Lange-Bertalot & Metzeltin, Hippodonta linearis (Østrup) Lange-Bertalot, Metzeltin & Witkowski, Stauroneis anceps Ehrenberg and Nitzschia solita Hustedt). These data sets represent a contribution to the understanding of mud volcanoes'output, of their influence on the environment and to the understanding of deep and shallow fluids in mud volcano systems.

Simion D.,INCDTP Division Leather and Footwear Research Institute | Niculescu O.,INCDTP Division Leather and Footwear Research Institute | Gaidau C.,INCDTP Division Leather and Footwear Research Institute | Simion M.,INCD ECOIND | And 2 more authors.
Leather and Footwear Journal | Year: 2011

he influence of surfactants upon the wettability of some hydrophobic microporous membranes of polysulphone was studied by determining the contact angle and the ultrafiltration rates. The water-membrane contact angle increases with roughness and changes in presence of the surfactant in aqueous solution to an extent which depends on its nature and concentration. The variations of contact angle of surfactant in aqueous solution are in good agreement with the variation of the rate of ultrafiltration solutions through membranes and with the adsorption of surfactants on polysulphone surface. The method of measuring the contact angle is simple and rapid; it may be employed in characterization of polysulphone membrane, hydrophobicity in spite of the scattering of values obtained of microporous surfaces.

Teodorescu M.,INCD ECOIND | Hlevca C.,INCD ICCF | Cosma C.,INCD ECOIND | Stefanescu M.,INCD ECOIND | And 2 more authors.
Revista de Chimie | Year: 2013

Protection of different active ingredients is recognized as quite an old practice (in 1931 gelatine microspheres were obtained by coacervation process) and it quickly developed, with applications in pharmaceutical, textile and food industries, and lately for products applied in agriculture. Coating or encapsulating different chemicals implies placing an external "shell", with protective role, on a core of active ingredient. The final product is a micro-particle, under the form of individual core-shell micro-capsule or a matrix, with more active particulates embodied in. Many physical and chemical techniques have been used for packing ingredients, which were, in most of the cases, chemical substances amenable to be consumed I self-depleted before being active for a specific role. For application in environmental technologies a major challenge is raised by the high chemical reactivity of reagents, especially oxidants, often used for the synthesis or chemical transformation of the potential shell materials. Still, some oxidants were reported to have been packed (Sodium Persulfate or Percarbonate, Potassium Permanganate, too), and the final products were particles in the range of hundreds m - cm, which released the oxidant in interval of hours - days. Obtaining microcapsules in the range of micrometric size (< 100 μ m), with slow regent release is an additional challenge. More preparation methods were experimentally developed (e.g. in-situ polymerization, coacervation or double layer coating) for Potassium Permanganate coating. Better results are obtained when using physical methods, although the economical feasibility is questionable even when using the most cost-efficient methods.

Vilcu C.,INCD Gas Turbines COMOTI | Voicu G.,UPB | Paraschiv G.,UPB | Manole E.S.,USAMV | And 3 more authors.
Environmental Engineering and Management Journal | Year: 2014

The dynamic monitoring system continuously performs the monitoring of physicochemical quality indicators of water quality in investigated areas. In case of ecological risk due to accidental pollution situations, the system alarms in real time the decision factors for the diminution of the environmental impacts and other negative effects. The distributed networks of the system are composed of floatable structures of Buoys Monitoring (BM) type, autonomous and adaptable to the environmental conditions specific to a continental climate. They are able to work with reduced maintenance in isolated locations. The BM floatable structure incorporates the sensors and the hardware-software system of data acquisition, processing and transmission. So equipped, BM becomes operational instrument in the infrastructure of the networks of surface waters quality monitoring. The BM model developed allows the continuous in situ evaluation of the health status of the monitored surface water with the scope of warning in case of ecological risk. © 2014, (publisher). All Rights Reserved.

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