The Freezing Points of Aqueous Solutions. IV. Potassium, Sodium and Lithium Chlorides and Bromides

1933 ◽  
Vol 55 (11) ◽  
pp. 4355-4362 ◽  
Author(s):  
George Scatchard ◽  
S. S. Prentiss
Keyword(s):  
Aqueous Solutions ◽  
Potassium Sodium ◽  
Freezing Points

THE FREEZING POINTS OF AQUEOUS SOLUTIONS. II. POTASSIUM, SODIUM AND LITHIUM NITRATES

1932 ◽  
Vol 54 (7) ◽  
pp. 2690-2695 ◽  
Author(s):  
George Scatchard ◽  
S. S. Prentiss ◽  
P. T. Jones
Keyword(s):  
Aqueous Solutions ◽  
Potassium Sodium ◽  
Freezing Points

PRODUCTION AND PROPERTIES OF 2,3-BUTANEDIOL: XII. ANTIFREEZE PROPERTIES OF TERNARY AQUEOUS SOLUTIONS CONTAINING LEVO-2,3-BUTANEDIOL AS A MAJOR COMPONENT

1946 ◽  
Vol 24f (5) ◽  
pp. 287-299 ◽  
Author(s):  
K. A. Clendenning ◽  
D. E. Wright
Keyword(s):  
Ethylene Glycol ◽  
Aqueous Solutions ◽  
Boiling Point ◽  
Freezing Point ◽  
Ternary Systems ◽  
Freezing Points ◽  
Point Depressant ◽  
Point Data ◽  
Considerable Range

Freezing point, viscosity, and boiling point data are presented for aqueous solutions of levo-2,3-butanediol containing methanol, ethanol, ethylene glycol, and tetrahydrofurfuryl alcohol as third components. All four ternary systems show freezing points of −50 °C. and lower over a considerable range of compositions. Among the compounds tested as third components, methanol was most effective as a thinning agent and accessory freezing point depressant. The data indicate that 20% methanol–40% butanediol–40% water is suitable for use at temperatures as low as −50 °C.

scholarly journals Bacterial growth tolerance to concentrations of chlorate and perchlorate salts relevant to Mars

2016 ◽  
Vol 16 (3) ◽  
pp. 229-235 ◽  
Author(s):  
Amer F. Al Soudi ◽  
Omar Farhat ◽  
Fei Chen ◽  
Benton C. Clark ◽  
Mark A. Schneegurt
Keyword(s):  
Aqueous Solutions ◽  
Bacterial Growth ◽  
Bacterial Isolates ◽  
Polar Cap ◽  
Planetary Protection ◽  
Freezing Points ◽  
Microbial Tolerance ◽  
High Concentrations ◽  
Chemical Conditions ◽  
The Phoenix

AbstractThe Phoenix lander at Mars polar cap found appreciable levels of (per)chlorate salts, a mixture of perchlorate and chlorate salts of Ca, Fe, Mg and Na at levels of ~0.6% in regolith. These salts are highly hygroscopic and can form saturated brines through deliquescence, likely producing aqueous solutions with very low freezing points on Mars. To support planetary protection efforts, we have measured bacterial growth tolerance to (per)chlorate salts. Existing bacterial isolates from the Great Salt Plains of Oklahoma (NaCl-rich) and Hot Lake in Washington (MgSO4-rich) were tested in high concentrations of Mg, K and Na salts of chlorate and perchlorate. Strong growth was observed with nearly all of these salinotolerant isolates at 1% (~0.1 M) (per)chlorate salts, similar to concentrations observed in bulk soils on Mars. Growth in perchlorate salts was observed at concentrations of at least 10% (~1.0 M). Greater tolerance was observed for chlorate salts, where growth was observed to 2.75 M (>25%). Tolerance to K salts was greatest, followed by Mg salts and then Na salts. Tolerances varied among isolates, even among those within the same phylogenetic clade. Tolerant bacteria included genera that also are found in spacecraft assembly facilities. Substantial microbial tolerance to (per)chlorate salts is a concern for planetary protection since tolerant microbes contaminating spacecraft would have a greater chance for survival and proliferation, despite the harsh chemical conditions found near the surface of Mars.

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