Experimental Study of a Minitype Atmospheric Non-equilibrium Plasma Source

A mini-type of plasma source was studied experimentally. The results showed that the plasma density, which was generated by an atmospheric non-equilibrium plasma source, rises with the increase in driving electric-field and the momentum of gas particles. For a driving electricfield of 56 kV/cm and a gas particles＇ momentum of 10^9 × 10^-22 g·m/s, the ion density can exceed 10^10/cm^3 while the effective volume of the plasma source is only 2.5 cm^2. This study may help develop a method to generate a minitype plasma source with low energy consumption but high ion concentration. This source can be used in chemical industry, environmental engineering and military applications.

Characteristics of urban ozone level in Hong kong

The long term trend of ozone level in Hong Kong has been investigated. One of the characteristics of ozone level in Hong Kong is the existence of autumn maximum and summer minimum. Observations of the diurnal variation of ozone level have been made in different area categories. There are early morning peak and afternoon peak occurred in the diurnal variation, which are different from some metropolitans where only an afternoon peak is observed. A negative correlation coefficient was found between monthly ozone level with nitric oxide level. On the contrary, there is a positive correlation between ozone and nitrogen dioxide. The positive correlation coefficient between nitric oxide and nitrogen dioxide shows that the total amount of nitric oxide emitted from a series of moving and fixed sources greatly exceeded the stoichiometric amount of ozone formed from chemical reactions of precursors and long distance transportation.

Photon-Ion-Catalyzed Rare Earth Functional Synergy Material

Large quantity of negative ions and hydrogen can be produced continuously by metal ions of tourmaline under the synergy action of light, water and oxygen. In order to promote this effect, the photon-ion-catalyzed rare earth functional synergy material was prepared to simulate the nature properties of tourmaline. Its safety was discussed and an interaction model proposed. The investigation results show that the cooperation of sunlight, valency-variable rare earth element thorium includes material and photo-catalyzed TiO_2 can increase the product of free radicals and negative ions. It is safety to use thorium included rare earth or rare earth waste with radiant dose smaller than 1Gy.

Rare Earth Materials Activate Diesel Oil

The properties of rare earth materials activated diesel oil such as temperature, density and hydroxylic radical were discussed. Rare earth materials including minim thorium oxide powders which had radioactivity were mainly composed of rare earth waste-residue powders. Under the radiation catalysis of rare earth materials, molecules of diesel oil can be transformed into activated molecules, the collision frequency increases among molecules, and temperature raises a little higher than usual. When temperature is higher, the interaction force between molecules is lessened, distance between molecules is shortened. The volume is increased and the density is decreased. A large amounts electrons and negative ions are produced by rare earth materials, which leads to the signals of hydroxylic radical stronger that means rare earth materials can activate diesel oil and can improve the activity of diesel oil.

The minimization of non-equilibrium plasma source at high pressure

The density of plasma produced by atmospheric non-equilibrium plasma source is the function of en-ergy dissipation rate in ionization electric field and gas particles momentum.The experiment shows that the plasma density highly rises with the increasing of energy dissipation rate and gas particles momentum.When the energy dissipation rate of activation field is 2.18 Wh/m3 and the average gas particles momentum is 109×10-22 g·m/s,the air throughput of plasma source whose volume is only 2.5 cm3 can be up to 12 m3/h and the density of plasma can be up to 1010 cm-3.The research can develop a method of producing minitype plasma source which is low energy consumption but high ion concen-tration used for chemical industry,environmental engineering and military.

Preliminary study of groundwater denitrification using a composite membrane bioreactor

A composite membrane bioreactor(CMBR)integrating the immobilized cell technique and the membrane separation technology was developed for groundwater denitrification.The CMBR had two well mixed compartments with one filled with the nitratecontaining influent and the other with a dilute ethanol solution;the compartments were separated by the composite membrane consisting of a microporous membrane facing the influent and an immobilized cell membrane facing the ethanol solution.Nitrate and ethanol molecules diffused from the respective compartments into the immobilized cell membrane where nitrate was reduced to gaseous nitrogen by the denitrifying bacteria present there with ethanol as the carbon source.The microporous membrane was attached to one side of the immobilized cell membrane for retention of the disaggregated bacteria.Relative to the single dose of external ethanol,the twodose supplementation produced better treatment results as evidenced by the lower concentrations of NO_(3)^(-)-N and ethanol(as measured by total organic carbon)of the effluent.The batch treatment in CMBR removed most of the nitrate in the influent and attained a stable denitrification rate of 0.1 g·m^(-2)·h^(-1)for most of the 96-h cycles during the 30-cycle study.The effluent was essentially free of ethanol and nitrite nitrogen.