scholarly journals SOME PHYSICOCHEMICAL PROPERTIES OF DISSOCIATED SPONGE CELLS

1926 ◽  
Vol 10 (2) ◽  
pp. 239-255 ◽  
Author(s):  
P. S. Galtsoff ◽  
Vladimir Pertzoff
Keyword(s):  
Physicochemical Properties ◽  
Weak Acid ◽  
Hydrogen Ion ◽  
Acid Solutions ◽  
Average Value ◽  
Cliona Celata ◽  
Number Of Cells

1. The activity of the hydrogen ion, in a system containing 0.00280 mols of NaAc, 0.520 mols of NaCl per liter, and varied amounts of HCl or NaOH has been investigated. The average value of pK' for acetic add in this system is about 4.37. 2. The effect of the addition of various amounts of HCl and NaOH to a system containing 0.00280 mols of NaAc, 0.520 mols of NaCl, and a known number of cells of either Microciona prolifera or Cliona celata was then studied. It was found that in weak acid solutions Microciona behaves as a stronger base than Cliona, the former being practically saturated with base at a pH of 7.5. Similar behavior is shown by suspensions of cells to which no acid or base was added: the cells of Cliona are more acidic than the cells of Microciona. 3. The microscopic examinations of the cells subjected to the treatment with acid or base indicate that the cells of Microciona remain alive down to pH 4.50; the cells of Cliona sustain greater acidity,— a,t pH 3.7 they exhibit no signs of cytolysis. Tests for aggregation of these cells showed that this phenomenon is greatly inhibited even by slightly acid solutions. 4. The conclusion is drawn that the concentration of cells being equal, the suspensions of cells of Microciona and Cliona differ from each other in their physicochemical properties, the comparison being made on suspensions of specified composition.

scholarly journals THE PHAGOCYTOSIS OF SOLID PARTICLES

1923 ◽  
Vol 5 (3) ◽  
pp. 311-325 ◽  
Author(s):  
Wallace O. Fenn
Keyword(s):  
Manganese Dioxide ◽  
Solid Particles ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Alkaline Solutions ◽  
Carbon Electrode ◽  
Acid Solutions ◽  
Small Particles ◽  
Hydrogen Ion Concentration ◽  
Electrode Potentials

1. Leucocytes ingest quartz particles more readily than carbon in acid solutions, and carbon more readily than quartz in alkaline solutions. 2. In the presence of acacia carbon is always preferred to quartz even in acid solutions. 3. Manganese dioxide particles are ingested by leucocytes with extraordinary rapidity as compared with manganese silicate or quartz. 4. Leucocytes are not attracted toward carbon or quartz particles but manganese dioxide exerts a distinct attraction for them. 5. Spores of Penicillium are ingested more readily than quartz. 6. Very small quartz particles, 1 micron in diameter, are not ingested as readily as larger particles of the same material. This result being contrary to the predictions of surface tension indicates that some other factor is involved in the ingestion of these small particles. 7. Measurements of the carbon electrode potentials and the cataphoretic charges on the particles have failed to supply an explanation for the varying relative rates of ingestion of carbon and quartz with varying hydrogen ion concentration.

scholarly journals Paired electrolysis for simultaneous electrochemical water softening and production of weak acid solutions

2019 ◽  
Vol 101 ◽  
pp. 88-92 ◽  
Author(s):  
Ignacio Sanjuán ◽  
Vicente García-García ◽  
Eduardo Expósito ◽  
Vicente Montiel
Keyword(s):  
Weak Acid ◽  
Acid Solutions ◽  
Water Softening

Hydrogen ion equilibria in poly(methacrylic acid) and poly(ethacrylic acid) solutions

Polymer ◽  
1981 ◽  
Vol 22 (3) ◽  
pp. 415-417 ◽  
Author(s):  
Desmond E. Joyce ◽  
Tomas Kurucsev
Keyword(s):  
Methacrylic Acid ◽  
Hydrogen Ion ◽  
Acid Solutions

scholarly journals SOME CONSEQUENCES OF THE THEORY OF MEMBRANE EQUILIBRIA

1925 ◽  
Vol 9 (1) ◽  
pp. 97-109 ◽  
Author(s):  
David I. Hitchcock
Keyword(s):  
Membrane Potential ◽  
Osmotic Pressure ◽  
Ionization Constant ◽  
Weak Acid ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Weak Base ◽  
Acid Base ◽  
Hydrogen Ion Concentration ◽  
Pass Through

In applying Donnan's theory of membrane equilibria to systems where the non-diffusible ion is furnished by a weak acid, base, or ampholyte, certain new relations have been derived. Equations have been deduced which give the ion ratio and the apparent osmotic pressure as functions of the concentration and ionization constant of the weak electrolyte, and of the hydrogen ion concentration in its solution. The conditions for maximum values of these two properties have been formulated. It is pointed out that the progressive addition of acid to a system containing a non-diffusible weak base should not cause the value of the membrane potential to rise, pass through a maximum, and fall, but should only cause it to diminish. It is shown that the theory predicts slight differences in the effect of salts on the ion ratio in such systems, the effect increasing with the valence of the cation.

Detachment of Pseudomonas fluorescens P26 from Beef Rinsed in Salt and Acid Solutions

1984 ◽  
Vol 47 (7) ◽  
pp. 537-541 ◽  
Author(s):  
C. P. APPL ◽  
R. T. MARSHALL
Keyword(s):  
Pseudomonas Fluorescens ◽  
Phosphate Buffer ◽  
Chloride Salt ◽  
Acid Solutions ◽  
Salt Solutions ◽  
Large Loss ◽  
Bacterial Surfaces ◽  
Citrate Phosphate ◽  
Number Of Cells ◽  
Citrate Phosphate Buffer

The purpose of this study was to test the hypothesis that numbers of bacteria detached from meat could be increased by modification of the ionic environment surrounding both the meat and bacterial surfaces. Of five 0.1 M chloride salt solutions that were used to rinse cells of Pseudomonas fluorescens P26 from meat, KCl removed the highest average number of cells. These numbers were significantly greater than those for NH4Cl and MgCl2. Compared with water, the solution of 0.1 M KCl rinsed three times as many bacteria from cubes of inoculated meat shaken in solution for 1 min and there were one-half as many bacteria recovered from meat rinsed with KCl as from meat rinsed with water. The latter difference was significant, and we conclude that KCl assisted in detachment of the pseudomonads. However, no significant effect of 0.1 M KCl was observed when it was added to water that had been buffered to pH 4 and 5 with citrate-phosphate buffer. Instead, the buffered rinse caused a large loss in viability of the pseudomonads. This large loss in viability may have over-shadowed the smaller effect of KCl.

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