METHOD FOR NITRATE DETERMINATION IN WATER IN THE PRESENCE OF NITRITE

Abstract. The study relates to determination of nitrate in presence of nitrite in water and can be used in the quality monitoring of natural water (surface and groundwater), drinking water, water from fi sh farms and public aquaria where autonomous fi lters is used. The nature and quantity of reagents used have insignifi cant impact on natural waters and sewages. According to the investigation, the method includes the removal of nitrite from the solution/water with sulfaminic acid, the nitrate ion reduction to nitrite using a reducing mixture that contains Na 2 SO 4 and zinc dust in ratio of 100:5 and determining the nitrite with the Griess reagent

Efficient Microbial Decontamination of Translucent Liquids and Gases Using Optical Metamaterials

An effective way of decontamination using optical metamaterials like photonic crystals consisting of glass microspheres or granulated quartz with various geometries is proposed. The efficient decontamination using the evanescent zone of metamaterials opens a new perspective in pathogen decontamination. We propose different topological structures of metamaterials to enlarge the contact surface of ultraviolet radiation with polluted translucent fluids. The approach is based upon the increased transfer of UV radiation via evanescent waves of metamaterials into contaminated translucent fluids. A series of experimental estimations of the decontamination rate of this type of metamaterials have been made. For these investigations, a decontamination core filled up with metamaterials is used through which the contaminated fluid freely flows. Experiments have conclusively proved that evanescent zone of quartz and optical fiber metamaterials can effectively inactivate Coliform (including Escherichia coli), or Enterococcus bacteria, as well as yeast and Kombucha cultures

METHOD FOR NITRATE DETERMINATION IN WATER IN THE PRESENCE OF NITRITE

The study relates to determination of nitrate in presence of nitrite in water and can be used in the quality monitoring of natural water (surface and groundwater), drinking water, water from fish farms and public aquaria where autonomous filters is used. The nature and quantity of reagents used have insignificant impact on natural waters and sewages. According to the investigation, the method includes the removal of nitrite from the solution/water with sulfaminic acid, the nitrate ion reduction to nitrite using a reducing mixture that contains Na2SO4 and zinc dust in ratio of 100:5 and determining the nitrite with the Griess reagent

THE WATER SPRINGS - SOURCES FOR WATER SUPPLY AND IRRIGATION IN THE NISTRU RIVER BASIN

The present study estimates chemical composition and status of the groundwater from the Dniester river basin. Research includes defining of springs/fountains location, evaluating physicochemical features of water, highlighting of main pollutants and pollution sources, establishing of water type and quality. The research was achieved within the State Program "Scientific research and water quality management"

ECOLOGICAL POTENTIAL OF SURFACE WATERS IN NATURAL SCIENTIFIC RESERVE “LOWER PRUT”

The research results have marked a low value of the self-purification capacity for Beleu Lake water, between 0.12 and 0.19, which is of 1.2-2 times smaller than the one from Prut River (0.25), correlating positively with the values of BOD5, COD-Cr and the time of biochemical oxidation of ammonium ions. The evolution of stage NH4+(NH3) → NO2- in the process of nitrification in lake water in November 2014 takes place about 25 days and the process NO2- → NO3- - more than 35 days, the duration about 2 times higher than in lake water stages from 2015 and 2.8-3.0 times higher than that of the model with water from Prut River