Search

Search Results

• A simple method for preparing elemental selenium nano- coating inside a silicone surface

  35-43

  Khandsuren Badgar

  József Prokisch

  Views:

  274

  Selenium nanoparticles (SeNPs) with a bright red colour have aroused worldwide attention due to their unique properties in selenium supplementation because of their low toxicity and favourable bioavailability. A simple method was developed for making a red selenium nanolayer on the inner surface of Polyvinyl chloride (PVC) and silicone tube. The selenium nanoparticles were produced by the reaction of sodium selenite and ascorbic acid. Red amorphous selenium nanoparticles have been successfully synthesized by the reaction of 500 mg dm^-3 Se (sodium selenite) solution with 10 g dm^-3 ascorbic acid solution at room temperature, and morphology was confirmed by X-ray diffraction analysis (XRD). The coating density was compared on PVC and silicone surfaces by using Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray (EDS) analysis. The nanolayer with about 16 µm thickness on the silicone surface significantly evenly distributed compared to the PVC surface. The selenium coated silicone tube could be a good source of selenium for a continuous, low-level selenium supplementation of farm animals via drinking water.

• Sight-specific development of the tools for the measurement of CO2-emission of the soil

  53-58

  Györgyi Kovács

  Nikolett Szőllősi

  Views:

  97

  Soil is the main source and at the same time the potential sink of greenhouse gases (e.g. CO₂, CH₄). Measurements were carried out in the experimental sites (soil tillage experiments and an extensive pasture) of the Karcag Research Institute of University of Debrecen, Centre for Agricultural Sciences to determine the CO₂-emission of the soil. The in situ CO₂-emission of soil was measured by means of an ANAGAS 98 infrared gas analyser in plastic (PVC) chambers, but this previously applied method (cylinders) was not suitable for the soil surface covered with grass,
  hence a new instrument was needed to be invented. In order to measure CO₂-emission on a larger area without deep disturbance of the soil, a special metal frame was created with a matching bowl. The most problematic part was the spatial delimitation of the measurement area as the surface of the soil can be very various and proper isolation is a must. We consider the frame+bowl method we developed suitable for measuring CO₂-emission of pastures as well as other crop-fields.