Unusual Response of a Cupric Ion Electrode in Prairie Lake Waters

1978 ◽  
Vol 35 (1) ◽  
pp. 141-143 ◽  
Author(s):  
J. Barica
Keyword(s):  
Key Words ◽  
Water Analysis ◽  
Natural Waters ◽  
Hard Water ◽  
Specific Conductance ◽  
Deionized Water ◽  
Canadian Prairies ◽  
Water Solutions ◽  
Cupric Ion ◽  
Lake Waters

The Orion cupric ion electrode exhibited the theoretical (Nernstian) response of 29–30 mV per concentration decade in deionized water solutions, but in certain moderately alkaline and moderately saline natural waters of the Canadian prairies (pH 7.8–8.6, specific conductance 950–6550 μS/cm) the response to added cupric ion of over 100 μg Cu/L was twice as great. The electrode was, nevertheless, usable in natural waters provided that calibration was made with water from the same source. Key words: water analysis (chemical), cupric ion electrode, copper, hard water

Survival of Two Bacterial Fish Pathogens (Aeromonas salmonicida and the Enteric Redmouth Bacterium) in Ozonated, Chlorinated, and Untreated Waters

1977 ◽  
Vol 34 (3) ◽  
pp. 429-432 ◽  
Author(s):  
Gary A. Wedemeyer ◽  
Nancy C. Nelson
Keyword(s):  
Lake Water ◽  
Contact Time ◽  
Free Water ◽  
Hard Water ◽  
Etiologic Agent ◽  
Aeromonas Salmonicida ◽  
Distilled Water ◽  
Fish Pathogens ◽  
Chlorine Residual ◽  
Lake Waters

Ozone and chlorine inactivation curves were determined in three water types at 20 °C for the destruction of the fish pathogens Aeromonas salmonicida, the etiologic agent of furunculosis, and the enteric redmouth bacterium (ERM). In phosphate-buffered distilled water, 0.01 mg/ℓ ozone inactivated 103 cells/ml of ERM and A. salmonicida in 1/2 and 10 min, respectively. Chlorine at this concentration had little effect on either pathogen and a residual of at least 0.05 mg/ℓ was needed to achieve a complete kill within a 10-min contact time. In soft lake water (30 mg/ℓ as CaCO3) a chlorine residual of 0.1 mg/ℓ rapidly [Formula: see text] inactivated A. salmonicida and ERM but in hard water (120 mg/ℓ) A. salmonicida was more resistant and 0.2 mg/ℓ chlorine was required. Ozonation of the two lake waters at 90 mg O3∙h−1∙ℓ−1 (equivalent to a 0.01 mg/ℓ residual in ozone demand-free water) was required to destroy both pathogens within 10 min.In untreated soft lake water 103 cells/ml of A. salmonicida survived only 2 days, while the ERM bacterium (103 cells/ml) survived even after 20 day s in soft and hard untreated lake waters.

scholarly journals Distribution Characteristics and Influencing Factors of Uranium Isotopes in Saline Lake Waters in the Northeast of Qaidam Basin

Minerals ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 74
Author(s):  
Chen Zhao ◽  
Pu Zhang ◽  
Xiangzhong Li ◽  
Youfeng Ning ◽  
Liangcheng Tan ◽  
...  
Keyword(s):  
Influencing Factors ◽  
Saline Lakes ◽  
Natural Waters ◽  
Qaidam Basin ◽  
Influencing Factor ◽  
Dominant Factor ◽  
Uranium Isotopes ◽  
Distribution Characteristics ◽  
Total Dissolved Solid ◽  
Lake Waters

Four saline lakes in the northeast of Qaidam Basin were selected to explore the distribution characteristics and influencing factors of uranium isotopes in lake waters with high evaporation background. The 238U concentration and the activity ratios of 234U/238U ([234U/238U]AR) showed that there was no significant change in the same lake, but there was a certain degree of difference in the distribution between different lakes. We found that aqueous 238U concentration within a certain range increased with an increase in TDS (total dissolved solid) and salinity, as was also the case with pH. As in natural waters, the pH affects the speciation of 238U, but TDS and salinity affect the adsorption process of aqueous 238U. Further, the replenishment of water will also affect the uranium isotope concentration for lakes, but it is not the main influencing factor for saline lakes. Therefore, we suggest that pH is the dominant factor affecting changes in aqueous 238U concentration of the sampled saline lakes. The [234U/238U]AR in these saline lakes are closely related to the input water and the associated water–rock interactions involving sediments, atmosphere dust, and organic material, etc. during the evolution stage, metamorphous degree, and hydrochemistry of the saline lakes. Lake water samples collected in the maximum and minimum discharge water period, were used to evaluate the seasonal distribution characteristics of aqueous 238U, and we found that 238U concentration did not show an evident change with the seasons in these saline lakes. If the 238U concentration and [234U/238U]AR can remain consistent during a period of time, then the sediment ages and/or sedimentation rates could be determined by lake sediment and/or biogenic carbonate in future, thus allowing for the accurate reconstruction of the paleoclimate and paleoenvironment.

Detection of heavy metal toxicity and genotoxicity in wastewaters by microbial assay

1994 ◽  
Vol 30 (10) ◽  
pp. 145-151 ◽  
Author(s):  
J. C. Codina ◽  
A. Pérez-García ◽  
A. de Vicente
Keyword(s):  
Escherichia Coli ◽  
Heavy Metals ◽  
Heavy Metal ◽  
Metal Toxicity ◽  
Ames Test ◽  
Deionized Water ◽  
Toxicity Tests ◽  
Water Solutions ◽  
Microbial Assay ◽  
Higher Sensitivity

The effect of wastewater on the sensitivity of toxicity and genotoxicity assays for the detection of heavy metals was evaluated. Five microbiological toxicity tests were used to compare the toxicity of cadmium, copper, chromium, mercury, nickel, and zinc, both in deionized water solutions and in wastewater. The toxicity assays employed were: Microtox®, two tests of growth inhibition using Pseudomonas fluorescens, and two spectrophotometric assays of the inhibition of respiration test using baker's yeast and P. fluorescens. Also, the genotoxic effect of the assayed metals was evaluated by using the Ames test, the Escherichia coli WP2 test, and the SOS test. The sensitivity to metals decreases in most of the toxicity and genotoxicity assays; in general, higher sensitivity thresholds (EC20) in wastewater than in water solutions were determined. Each test shows different sensitivities to each metal, which is related to different sensitivities of the organisms used in the assays, as well as to other factors.

The potential of mustard (Brassica juncea (L.) Coss) as an edible oil crop on the Canadian Prairies

1991 ◽  
Vol 71 (1) ◽  
pp. 195-198 ◽  
Author(s):  
D. L. Woods ◽  
J. J. Capcara ◽  
R. K. Downey
Keyword(s):  
Protein Content ◽  
Key Words ◽  
Brassica Juncea ◽  
Oil Content ◽  
Edible Oil ◽  
Canadian Prairies ◽  
Oil Crop

The performance of mustard (Brassica juncea (L.) Coss) was compared with that of canola (B. napus L. and B. rapa L.) on the western prairies. Mustard had a higher yield and protein content and was intermediate in maturity. Improvement in oil content will probably be required. Key words: Mustard, Brassica juncea, edible oil crop

Water Analysis by Selective Specific Conductance

1947 ◽  
Vol 19 (9) ◽  
pp. 657-660 ◽  
Author(s):  
J. W. Polsky
Keyword(s):  
Water Analysis ◽  
Specific Conductance

Soil science on the Canadian prairies - Peering into the future from a century ago

2001 ◽  
Vol 81 (4) ◽  
pp. 489-503 ◽  
Author(s):  
H H Janzen
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Key Words ◽  
Crop Rotation ◽  
Soil Science ◽  
Good Time ◽  
Grassland Soils ◽  
Canadian Prairies ◽  
The Future

Now, as a new century begins, may be a good time to reflect on the future of Soil Science on the Canadian prairies. One way to do that is to step back about one hundred years, to the turn of the previous century when our grassland soils were first cultivated. What questions perplexed scientists then? And how did they look for answers? My objective is to listen for our forebears’ thoughts in their writings, now largely buried. From this historical vantage may emerge insights, not only into where our science has been, but also into where it might yet go. Key words: Soil organic matter, crop rotation, grassland soils, history

EFFECT OF TYPE, RATE AND INCORPORATION OF LIME AND OF NITROGEN FERTILIZER AND GYPSUM ON MOVEMENT OF LIME IN SOIL COLUMNS

1986 ◽  
Vol 66 (4) ◽  
pp. 757-762
Author(s):  
P. B. HOYT ◽  
B. G. DROUGHT ◽  
G. H. NEILSEN ◽  
E. HOGUE
Keyword(s):  
Key Words ◽  
Soil Ph ◽  
Nitrogen Fertilizer ◽  
Soil Surface ◽  
Deionized Water ◽  
N Fertilizer ◽  
Soil Columns ◽  
Downward Movement ◽  
Type Rate

Soil columns were used to study downward movement of calcite and dolomite applied at two rates on the soil surface or incorporated 0–5 cm deep in combinations with gypsum and surface-applied N fertilizer. The columns were irrigated with 800 mm of deionized water applied over 3 wk. Incorporation of the liming materials greatly accelerated their downward movement in soil. Calcite and dolomite were equally effective in raising soil pH at the lower depths. Neither gypsum nor fertilizer nor doubling the liming rate had much effect on lime movement. Key words: Lime movement, calcite, dolomite, gypsum

Interaction of ions of heavy metals and organic toxicants with humic substances in system ‘atmospheric precipitation - lysimetric waters - lake waters’ of the Reserve of the European Territory of Russia: climatic, technogenic, geochemical fact

2021 ◽  
Author(s):  
Marina Dinu
Keyword(s):  
Heavy Metals ◽  
Organic Matter ◽  
Humic Substances ◽  
Natural Waters ◽  
Atmospheric Precipitation ◽  
Organic Substances ◽  
Alkaline Lake ◽  
Autochthonous Organic Matter ◽  
Lake Waters ◽  
Lysimetric Waters

<p>The reactions of toxicants with organic substances of a humic nature are complex and depend on many geochemical factors. Differences in the mechanisms of the selected toxicants binding with organic natural substances of various natural waters - atmospheric precipitation, lake waters (acidic and alkaline), lysimetric waters are especially interesting. Due to significant concentration differences, features of functional groups and size distribution of components, the inactivation features of humic substances are selective and highly variable. We studied the waters of an acid lake near the city of Valday (Valday National Park, conditionally a background lake) and alkaline lake Valday (city of Valday, local technogenic influence). Near each lake there was a sediment collector (a container for collecting atmospheric precipitation) and a lysimeter (a container under the soil for collecting soil moisture) under the humus horizon (about 20 cm). Particular attention was paid to soil (lysimetric) waters with varying degrees of anthropogenic impact. We considered the behavior of a large group of heavy metals, as well as benzopyrene. To assess the composition and qualitative features of organic substances, gas chromatography-mass spectrometric methods of analysis were used. Chromatographic methods were used to assess the molecular weight distribution of the components. Possible reaction mechanisms were studied by IR spectral methods. Evaluation of the reactivity of organic substances was carried out by the methods of dynamic light scattering (zeta potential, MM, size) using the "Zeta-sizer nano". In addition to humic substances in the waters, the contents of autochthonous organic matter were estimated, especially in an alkaline lake, which in some periods prevailed over humic ones. In addition to humic substances in the waters, the contents of autochthonous organic matter were estimated, especially in an alkaline lake, which in some periods prevailed over humic ones. For separation, exchange technique and fluorometric evaluations were used. We conducted research in the period 2015-2020, sampling was carried out in spring, summer, autumn. Thus, we studied the circulation (in miniature) of changes in the protective properties of humic substances, depending on a large number of factors.</p>

Conductivity and the concentration of total dissolved soilds in Australian lakes

1966 ◽  
Vol 17 (2) ◽  
pp. 169 ◽  
Author(s):  
WD Williams
Keyword(s):  
Saline Lakes ◽  
Total Dissolved Solids ◽  
Specific Conductance ◽  
Dissolved Solids ◽  
Wide Range ◽  
Lake Waters ◽  
The Relationship

The relationship between specific conductance and concentration of total dissolved solids was investigated in 62 samples from Australian lakes over a wide range of concentration of total dissolved solids (from 0.5 to >200‰). A high correlation was found particularly in highly saline lakes. This suggests that with much greater confidence than elsewhere conductivity determinations may be used in Australia as an indication of the amounts of total dissolved solids in lake waters over a wide range of concentration.

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