The geochemistry of surface waters of the Western District of Victoria

1967 ◽  
Vol 18 (1) ◽  
pp. 35 ◽  
Author(s):  
GE Maddocks
Keyword(s):  
Sea Water ◽  
Salinity Range ◽  
Strontium Chloride ◽  
Sodium Potassium ◽  
Ionic Ratios ◽  
Extreme Salinity ◽  
Inorganic Constituents ◽  
Dominant Cation ◽  
Total Salinity ◽  
Potassium Magnesium

Chemical data are presented for the concentrations of sodium, potassium, magnesium, calcium, strontium, chloride, bromide, sulphate, carbonate, boron, silicon, phosphorus, and nitrogen in some lakes and rivers of the Western District of Victoria. All these waters are of the chloride type and sodium is the dominant cation. Comparatively high pH values are common. Several ionic ratios have been calculated and these are used to illustrate relative enrichments or losses among the ions present during an overall increase in total salinity. Precipitation of dolomitic carbonate is indicated. The similarity of several ionic ratios to those of sea water is used to propose an oceanic origin for these inorganic constituents. Clay membrane mechanisms coupled with solar evaporation are suggested as an explanation for the extreme salinity range of samples.

scholarly journals Regulation of Water and Some Ions in Gammarids (Amphipoda)

1971 ◽  
Vol 55 (2) ◽  
pp. 357-369
Author(s):  
D. W. SUTCLIFFE
Keyword(s):  
Sodium Chloride ◽  
Sea Water ◽  
Chloride Concentration ◽  
Sodium Concentration ◽  
Body Water ◽  
The Body ◽  
Salinity Range ◽  
Sodium Potassium ◽  
Body Sodium ◽  
Total Body

1. A comparison was made of the body water contents and the concentrations of sodium, potassium and chloride in the blood and body water of Gammarus zaddachi, G. locusta and Marinogammarus finmarchicus. 2. G. zaddachi had a slightly higher body water content than G. locusta and M. finmarchicus. 3. In all three species the blood chloride concentration was lower than the external chloride concentration in 80-113 % sea water, but the blood sodium concentration was equal to or slightly above the sodium concentration in the external medium. 4. The total body sodium concentration was always greater than the total body chloride concentration. In M.finmarchicus the ratio of body sodium/chloride increased from 1.2 to 1.3 over the salinity range 100-20% sea water. In G. zaddachi the ratio of body sodium/chloride increased from 1.08 at 100% sea water to 1.87 in 0.25 mM/l NaCl. 5. The total body potassium concentration remained constant. The potassium loss rate and the balance concentration were relatively high in G. zaddachi. 6. The porportion of body water in the blood space was calculated from the assumption that a Donnan equilibrium exists between chloride and potassium ions in the extracellular blood space and the intracellular space. In G. zaddachi the blood space was equivalent to 60% body H2O at 100% sea water, and equivalent to 50% body H2O at 40% sea water down to 0.5 mM/l NaCl. In M.finmarchicus the blood space was equivalent to 38-44% body H2O at salinities of 20-100% sea water. 7. The mean intracellular concentrations of sodium, potassium and chloride were also calculated. It was concluded that for each ion its intracellular concentration is much the same in the four euryhaline gammarids. The intracellular chloride concentration is roughly proportional to the blood chloride concentration. The intracellular sodium concentration is regulated in the face of large changes in the blood sodium concentration.

scholarly journals Impurity Concentrations In Sea Ice

1977 ◽  
Vol 18 (78) ◽  
pp. 117-127 ◽  
Author(s):  
J.R. Addison
Keyword(s):  
Sea Ice ◽  
Sea Water ◽  
Ion Concentration ◽  
Concentration Profiles ◽  
Sodium Potassium ◽  
Ambient Temperatures ◽  
The Third ◽  
Different Types ◽  
Potassium Magnesium

Abstract Three different types of saline ice were cut into sections a few millimeters thick along planes parallel to the surface. The resulting melts were analyzed quantitatively for chloride, sulphate, sodium, potassium, magnesium, and calcium. Two of the specimens were artificial sea ice, grown in the laboratory at ambient temperatures of —30°C and - 15°C, respectively. A portion of the latter exhibited a clear, glassy, fresh-ice structure. The third was natural sea ire. The resulting ion concentration profiles and ion ratios are presented. For sections of widely varying salinity, the various ion ratios assumed values fairly close to those in natural sea-water.

The Osmotic and Ionic Regulation of Artemia Salina (L.)

1958 ◽  
Vol 35 (1) ◽  
pp. 219-233 ◽  
Author(s):  
P. C. CROGHAN
Keyword(s):  
Osmotic Pressure ◽  
Sea Water ◽  
Artemia Salina ◽  
Chloride Ions ◽  
The Body ◽  
Distilled Water ◽  
Sodium Potassium ◽  
Rapid Fall ◽  
Water Media ◽  
Potassium Magnesium

1. It has been possible to adapt Artemia to sea-water media varying from 0.26% NaCl to crystallizing brine. In fresh water or distilled water survival is relatively short. 2. The osmotic pressure of the haemolymph is relatively independent of the medium and increases only slightly as the medium is made more concentrated. In the more concentrated media the haemolymph is very markedly hypotonic. In media more dilute than 25% sea water the haemolymph is hypertonic. In distilled water there is a rapid fall of haemolymph concentration. The haemolymph of nauplii from sea water is hypotonic. 3. The sodium, potassium, magnesium, and chloride concentrations of the haemolymph have been determined. The bulk of the haemolymph osmotic pressure is accounted for by sodium and chloride ions. The ionic ratios of the haemolymph are relatively constant, and very different from those of the medium. 4. The concentrations of ions in the whole animal have been studied. The chloride space is extremely high. Such changes in haemolymph osmotic pressure that do occur as the medium concentration is varied are due more to net movements of NaCl into or out of the body than to water movements. 5. Evidence is collected to show that an appreciable degree of permeability exists. Most of this permeability is localized to the gut epithelium, the external surface being much less permeable. 6. It is clear that Artemia must possess mechanisms that can actively excrete NaCl and take up water in hypertonic media. It has been demonstrated that Anemia can lower the haemolymph osmotic pressure by excreting NaCl from the haemolymph against the concentration gradient.

scholarly journals Ionic regulation in Carcinus maenas

1940 ◽  
Vol 129 (854) ◽  
pp. 107-136 ◽  
Keyword(s):  
Water Exchange ◽  
Sea Water ◽  
Carcinus Maenas ◽  
Ionic Regulation ◽  
Passive Permeability ◽  
Sodium Potassium ◽  
Active Absorption ◽  
Physiological Conditions ◽  
Branchial Epithelium ◽  
Inorganic Constituents

Analyses have been made, with respect to the principal inorganic constituents, of the blood and urine of Carcinus , when living in normal sea water, diluted sea water, and sea water modified by the addition of magnesium sulphate. The composition of the blood of individuals living in normal sea water is as follows (the concentration of each ion being expressed as a percentage of the concentration that would be expected if the blood were in dialysis equilibrium with the external medium): Na 110%, K 118%, Ca 108%, Mg 34%, Cl 104%, SO 4 61%. This ionic regulation is the resultant of the following processes: active absorption by the gills of sodium, potassium, calcium and chloride at a rate greater than that at which they are lost by diffusion ; differential excretion by the antennary gland, which tends to conserve potassium and eliminate magnesium and sulphate ; inward diffusion across the gills of magnesium and sulphate in accordance with the concentration gradient. In normal conditions there is active absorption of water. In dilute media, when osmoregulation begins, this is suspended, and possibly there is a fall in the passive permeability of the gills to water. In other respects osmoregulation is brought about by an intensification of the processes responsible for ionic regulation. The permeability of the cuticle under physiological conditions is such that it does not affect the salt and water exchange of the animal, which is controlled by the branchial epithelium. The structure of the gills of four species of Decapoda is described, and correlated with their powers of osmotic and ionic regulation.

scholarly journals Impurity Concentrations In Sea Ice

1977 ◽  
Vol 18 (78) ◽  
pp. 117-127
Author(s):  
J.R. Addison
Keyword(s):  
Sea Ice ◽  
Sea Water ◽  
Ion Concentration ◽  
Concentration Profiles ◽  
Sodium Potassium ◽  
Ambient Temperatures ◽  
The Third ◽  
Different Types ◽  
Potassium Magnesium

AbstractThree different types of saline ice were cut into sections a few millimeters thick along planes parallel to the surface. The resulting melts were analyzed quantitatively for chloride, sulphate, sodium, potassium, magnesium, and calcium. Two of the specimens were artificial sea ice, grown in the laboratory at ambient temperatures of —30°C and - 15°C, respectively. A portion of the latter exhibited a clear, glassy, fresh-ice structure. The third was natural sea ire. The resulting ion concentration profiles and ion ratios are presented. For sections of widely varying salinity, the various ion ratios assumed values fairly close to those in natural sea-water.

scholarly journals Metal Binding Proteins

Encyclopedia ◽  
2021 ◽  
Vol 1 (1) ◽  
pp. 261-292
Author(s):  
Eugene A. Permyakov
Keyword(s):  
Metal Ions ◽  
Metal Binding ◽  
Transition Metal Ions ◽  
Short Review ◽  
Sodium Potassium ◽  
Physical Chemical ◽  
Physiological Properties ◽  
Cell Processes ◽  
Living Organisms ◽  
Potassium Magnesium

Metal ions play several major roles in proteins: structural, regulatory, and enzymatic. The binding of some metal ions increase stability of proteins or protein domains. Some metal ions can regulate various cell processes being first, second, or third messengers. Some metal ions, especially transition metal ions, take part in catalysis in many enzymes. From ten to twelve metals are vitally important for activity of living organisms: sodium, potassium, magnesium, calcium, manganese, iron, cobalt, zinc, nickel, vanadium, molybdenum, and tungsten. This short review is devoted to structural, physical, chemical, and physiological properties of proteins, which specifically bind these metal cations.

The effect of dehydration and rehydration on salt loss in the second-stage larvae of Anguina tritici

Parasitology ◽  
1981 ◽  
Vol 82 (3) ◽  
pp. 411-419 ◽  
Author(s):  
C. Womersley
Keyword(s):  
Salt Content ◽  
Atomic Absorption Spectrophotometry ◽  
Sodium Content ◽  
Sodium Potassium ◽  
X Ray ◽  
Second Stage ◽  
Absorption Spectrophotometry ◽  
Nematode Cuticle ◽  
Calcium Loss ◽  
Potassium Magnesium

SUMMARYThe effect of repeated dehydration and hydration on the salt content of 2nd-stage larvae of Anguina tritici was studied. The sodium, potassium, magnesium and calcium contents of the larvae after subjection to varying periods of desiccation and rehydration were determined with atomic absorption spectrophotometry and flame photometry. External cation concentrations on the cuticle of the head, middle body and tail regions were determined semi-quantitatively with scanning electron microscopy in conjunction with X-ray analysis (EDAX). Salt concentrations decreased with each dehydration/rehydration cycle. The greatest loss occurred on revival from the first desiccation period. The results indicated that A. tritici was incapable of regulating it's internal sodium content during revival, but suggested a limited ability to control potassium, magnesium and calcium loss. Salt loss through the nematode cuticle was restricted to potassium and calcium during desiccation. The salt losses encountered are discussed in relation to nematode osmoregulation and to the survival of the nematode in the anhydrobiotic state.

scholarly journals The digestion process of the sugar alcohol isomalt in the intestinal tract of the pig

1993 ◽  
Vol 69 (2) ◽  
pp. 467-479 ◽  
Author(s):  
E. J. Van Weerden ◽  
J. Huisman
Keyword(s):  
Small Intestine ◽  
Dry Matter ◽  
Intestinal Tract ◽  
Live Weight ◽  
Feed Consumption ◽  
Slight Reduction ◽  
Sodium Potassium ◽  
Bacterial Fermentation ◽  
Digestion Process ◽  
Potassium Magnesium

In a study with ten pigs of 60–70 kg live weight, provided with a re-entrant cannula at the end of the ileum, and sixteen intact, non-cannulated pigs, the digestion and absorption of a dietary dose of 100 g isomalt/kg, and isomalt given between the meals as a ‘sweet’on the basis of 50 and 100 g/kg feed consumption, were examined. In all three isomalt treatments slightly less than 0.40 of the isomalt consumed was digested in the small intestine when the calculations were based on ileal sugar passage. However, when basing the calculations on energy contents of ileal chyme, only approximately 0.10 was digested in the small intestine. The bacterial fermentation of the isomalt flowing into the large intestine was indicated by a decreased faecal energy digestibility and a slight reduction in faecal dry matter and nitrogen digestibility. The retention of the minerals sodium, potassium, magnesium, calcium and phosphorus was not influenced to any measurable extent when isomalt was fed.

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