As its major removal process the photodissociat ion of a tmospheric C 1 0 N 0 2 in the ultraviolet is discussed. It has repeatedly been pointed out that significance should be at t r ibuted to the pathways of chlorine nitrate fo rmat ion and its destruction since this compound might be involved in the ozone depletion mechanism through both the C10x and N O x a tmospheric cycles. This communica ...

The activation of scheelite and wolframite by lead nitrate with benzohydroxamic acid (BHA) as collector was investigated by means of micro flotation test, zeta potential measurement, X-ray photoelectron spectroscopy (XPS) analyses and density functional theory (DFT) calculation. The flotation results confirmed that the addition of lead nitrate can markedly enhance the recovery of scheelite and ...

Passive samplers with two different collection substrates were used to obtain an average ozone concentration for 1 month during the summer of 2002 for each South Carolina county. One sampler contained a filter coated with indigo carmine, whose color fades when exposed to ozone. The fading was measured by reflectance spectroscopy. The other sampler contained filters that were coated with nitrite...

A multiphase chemistry model coupled with a quasi-spectral microphysical model has been applied to measurements from the European CIME campaign to quantify the formation of the strong acids nitrate and sulfate, and to evaluate the role of microphysical processes in redistributing reactive species among the different phases (gas versus cloud and/or rain). Significant formation of nitrate and sul...

C. 2. c. EFFLUENT VERSUS ABSORPTION AREA WATER QUALITY DURING THE RESEARCH STUDY Hydrogen ion concentrations (pH), EC values, and chloride ion concentrations remained consistent between effluent and subsystems samples each year. Effluent nitrate-N concentrations were lower and ammonium-N concentrations higher than those concentrations found within either subsystem in the absorption area. This w...

A rapid and sensitive spectrophotometric method for the determination of nitrate in vegetables is described. The method is based on the measurement of the absorbance of yellow sodium nitrophenoxide formed via the reaction of phenol with the vegetable-based nitrate in presence of sulphuric acid. The analytical concentration of the acid has marked effect on the nitrate determined. The colour deve...

An ion chromatography method was developed to determine trace anionic contamination in matrices that have a high concentration of nitrate ion. Contaminant anions of interest were separated on an IonPac AS15 high-capacity anion-exchange column and detected by suppressed conductivity detection. An EG40 eluent generator was used to prepare high-purity and carbonate-free potassium hydroxide. Using ...

background: surface water and groundwater pollution with various forms of nitrogen such as ammonium and nitrate ions is one of the main environmental risks. the major objectives of this study were to evaluate the capacity of natural zeolite (clinoptilolite) to remove no3- and nh4+ from polluted water under both batch and column conditions. methods: the laboratory batch and column experiments we...

Excessive use of nitrogen fertilizers has increased nitrate concentrations in groundwater, which poses a health hazard from nitrate-contaminated drinking water and contributes to eutrophication. Nitrate removal systems been carefully studied; However, new, low-cost solutions are urgently needed. Clay terracotta minerals commonly used environmental applications due their non-toxicity, global ava...

Every organism has different potential to accumulate NO3 from the environment. Nitrate reduction processes are perhaps most significant in maintaining water quality by alteration of nitrate to nitrite. A comparative study between the nitrate reductase NR activity of green and blue green algae in presence of heavy metals is being conducted to present a situation where nitrate reductase process m...