33 research outputs found

    Interaction of high-power microwave beams with metal-dielectric media

    No full text
    Results of experimental investigation of powerful microwave beams action on the metal-dielectric compositions are presented. Dielectric surfaces with introduced metallic grains as well as dielectric powder containing small admixtures of a metallic one have been explored as an objects of irradiation. At a relatively small microwave power (P≤1P \le 1 mW) all investigated targets were practically completely transparent for incident electromagnetic wave. At a relatively high power (microwave generators based on the gyratrons and powerful magnetrons) the irreversible changes in the electric and radiophysical properties of metal-dielectric composites exposed to microwave radiation whose intensity is below the threshold intensity for plasma production have been observed (sharp increase of conductivity and microwave absorption coefficient)

    Resonance phenomena in microwave nonmagnetized plasma source. Plasmachemical application

    No full text
    Scheme of coaxial microwave gas-discharge plasma source based on a “plasma resonance” phenomenon is presented. Possibility of conditions realization at which energy of accelerated in the “resonance” electrons goes into ionization processes (in volume of chamber outside of “resonance” region) is discussed. Results of experimental investigation of a coaxial microwave plasmatron in which “resonance” mechanisms have been manifested are presented. A plasmachemical reactor based on a “resonance” plasmatron is described. The data on plasmachemical decomposition of CF2Cl2 are displayed

    Fast combustion waves and chemi-ionization processes in a flame initiated by a powerful local plasma source in a closed reactor

    Get PDF
    One alternative biofuel to substitute fossil fuels is bioethanol. Microalgae Spirulina sp. contains high carbohydrates, which has 17-25% potential to produce bioethanol. Urea and NaHCO3 can be used as additional nutrients sources of nitrogen and carbon to Spirulina sp. cultivation. Deficiency of nitrogen causing the cell’s enzymes change that shown through decreased lipid and chlorophyll synthesis. While deficiency of carbon can affect the growth rate. In this research, the growth rate of Spirulina sp. is analyzed using Optical Density (OD) method. The growth rate calculation is used to measure the growth of microalgae cells shown in the growth curve. This was a laboratory-scale method using CRD with 4 treatments and 5 replications namely treatment A addition of 0.36 g/500 ml urea without addition of NaHCO3, treatment B addition of 0.043 g/500 ml NaHCO3 without addition of urea, treatment C addition of 0.36 g/500 ml urea and 0.043 g/500 ml NaHCO3, and control without addition of urea or NaHCO3. The results indicated that addition of urea and NaHCO3 didn’t affect to OD and Spirulina sp. growth rate. The highest growth rate was treatment A with 0.00906/day of growth rate followed by treatment C which has 0.00865/day of growth rate. Treatment B and control treatment (K) showed a low growth rate. The maximum OD value obtained in treatment C was 0.674 cells/ml on the 10th day. This research can be used as the reference to larger scale of Spirulina sp. cultivation in the field of bioethanol production
    corecore