scholarly journals Measuring Hydroxylammonium, Nitrate and Nitrite Concentration with Raman spectroscopy for 238Pu Supply Program

2021 ◽  
Author(s):  
Luke Sadergaski ◽  
Travis Hager
Keyword(s):  
Raman Spectroscopy ◽  
Nitrite Concentration ◽  
Hydroxylammonium Nitrate ◽  
Nitrate And Nitrite

Influence of ammonium, nitrate and nitrite on the performance of the pure culture of Acinetobacter junii

Biologia ◽  
2007 ◽  
Vol 62 (5) ◽  
Author(s):  
Jasna Hrenović ◽  
Yüksel Orhan ◽  
Hanife Büyükgüngör ◽  
Miroslav Horvatiček
Keyword(s):  
Ammonium Nitrate ◽  
Nitrogen Uptake ◽  
Pure Culture ◽  
Oxygen Demand ◽  
Nitrite Concentration ◽  
Phosphate Release ◽  
Acinetobacter Junii ◽  
Uptake Rates ◽  
Complete Failure ◽  
Nitrate And Nitrite

AbstractThe influence of different concentration ranges (0–500 mg/L) of ammonium, nitrate and nitrite presence in the wastewater, on the performance of the pure culture of phosphate-accumulating bacterium Acinetobacter junii in the anaerobic and aerobic conditions, was investigated. A. junii was able to use ammonium and nitrate salts as the source of nitrogen, unlike in the case of nitrite salt. Comparing to the control reactors with the peptone and yeast extract as the sources of nitrogen, at the lowest tested concentration of ammonium and nitrate the performance of the system was inhibited due to the nitrogen deficit in the wastewater, while at the highest concentration it was positively influenced. Nitrite in all concentrations detrimentally affected the phosphate release and uptake rates, chemical oxygen demand uptake rates, nitrogen uptake rates, as well as multiplication of A. junii. The higher the nitrite concentration, the more pronounced was the effect. At the highest nitrite concentration tested a complete failure of the system was observed.

Modeling, Optimization and Design of Fluidized Beds for Biological Denitrification

1985 ◽  
Vol 17 (2-3) ◽  
pp. 367-383 ◽  
Author(s):  
Th J. Nieuwstad
Keyword(s):  
Fluidized Beds ◽  
Optimal Conditions ◽  
Optimal Thickness ◽  
Nitrite Concentration ◽  
Standard Type ◽  
Constant Flow Rate ◽  
Zero Order Kinetics ◽  
Carrier Materials ◽  
Nitrate And Nitrite ◽  
Bed Expansion

A mathematical model for fluidized bed denitrification has been derived, based on the fluidization theory and on zero order kinetics for biological nitrate reduction with nitrite as an intermediate product. Bed expansion, particle size, sludge concentration and nitrate and nitrite concentration can be calculated as a function of the height in the bed. Complete optimal conditions were not found using carrier materials of various specific gravities and with sizes above a radius of 0.2 mm, which was arbitrarily chosen as the smallest carrier particle. However, for each size and type of carrier material an optimal thickness of the biomass layer has been calculated for a standard type of wastewater at constant flow rate. For the kinetic and other constants used in this study, graphs are presented which can be used in the design of fluidized beds for denitrification.

scholarly journals Spatio-temporal variation of nitrate and nitrite levels in groundwater samples from Romania

2020 ◽  
Vol 2 (2) ◽  
pp. 56-63
Author(s):  
Florinela Pirvu ◽  
Iuliana Paun ◽  
Florentina Laura Chiriac ◽  
Marcela Niculescu ◽  
Nicoleta Vasilache ◽  
...  
Keyword(s):  
Temporal Distribution ◽  
Nitrite Concentration ◽  
The North ◽  
Groundwater Samples ◽  
Geographical Regions ◽  
North Eastern ◽  
Spatio Temporal ◽  
Seasonal Indices ◽  
Nitrate And Nitrite

This study investigated the spatial and temporal distribution of nitrate and nitrite concentration in groundwater from different geographical regions, in Romania. A special emphasis was put on a descriptive statistical analysis of data, namely on the determination of seasonal indices during dry and wet seasons. Nitrate and nitrite concentrations were monitored in 24 groundwater sources situated in different areas, between January 2016 and February 2020. The obtained data showed that the values of nitrate concentrations were situated between 8.03 mg/L in the North-Eastern part of Romania, 6.37 mg/L in the South-Eastern part of the country, and 3.55 mg/L in the Western part towards the center of the country. Nitrite concentration values were situated under the national maximum admitted limit, 0.5 mg/L, in all the investigated areas. The obtained data shows small changes in water quality during the monitoring period, which leads to the conclusion that, in this long interval of time, there were no significant groundwater contaminations with nitrate and nitrite. For adequate control of water pollution and rigorous management of groundwater sources, seasonal indices were calculated.

High-nitrate vegetable diet increases plasma nitrate and nitrite concentrations and reduces blood pressure in healthy women

2015 ◽  
Vol 18 (14) ◽  
pp. 2669-2678 ◽  
Author(s):  
Ann Ashworth ◽  
Klaus Mitchell ◽  
Jamie R Blackwell ◽  
Anni Vanhatalo ◽  
Andrew M Jones
Keyword(s):  
Blood Pressure ◽  
Control Diet ◽  
Epidemiological Studies ◽  
Leafy Vegetables ◽  
Nitrite Concentration ◽  
Green Leafy Vegetables ◽  
Healthy Women ◽  
Significant Change ◽  
Plasma Nitrate ◽  
Nitrate And Nitrite

AbstractObjectiveEpidemiological studies suggest that green leafy vegetables, which are high in dietary nitrate, are protective against CVD such as stroke. High blood pressure (BP) is a major risk factor for stroke and inorganic nitrate has been shown to reduce BP. The objective of the present study was to test the hypothesis that diets containing high-nitrate (HN) vegetables would increase plasma nitrate and nitrite concentrations and reduce BP in healthy women.DesignA randomized, crossover trial, where participants received HN vegetables (HN diet) or avoided HN vegetables (Control diet) for 1 week. Before and after each intervention, resting BP and plasma nitrate and nitrite concentrations were measured.SettingUniversity of Exeter, UK.SubjectsNineteen healthy women (mean age 20 (sd2) years; mean BMI 22·5 (sd3·8) kg/m2).ResultsThe HN diet significantly increased plasma nitrate concentration (before HN diet: mean 24·4 (sd5·6) µmol/l; after HN diet: mean 61·0 (sd44·1) µmol/l,P<0·05) and plasma nitrite concentration (before HN diet: mean 98 (sd91) nmol/l; after HN diet: mean 185 (sd34) nmol/l,P<0·05). No significant change in plasma nitrate or nitrite concentration was observed after the Control diet. The HN diet significantly reduced resting systolic BP (before HN diet: mean 107 (sd9) mmHg; after HN diet: mean 103 (sd6) mmHg,P<0·05). No significant change in systolic BP was observed after the Control diet (before Control diet: mean 106 (sd8) mmHg; after Control diet: mean 106 (sd8) mmHg).ConclusionsConsumption of HN vegetables significantly increased plasma nitrate and nitrite concentrations and reduced BP in normotensive women.

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