Kenjiro Meguro

Action of surface-active agents on chloroplasts

Abstract The action of ionic and nonionic surface-active agents on chloroplasts isolated from spinach leaves was studied at two different hydrogen ion concentrations. At pH 7.0, the cationic agents act as flocculants at lower concentrations and as lytic agents at higher concentrations, whereas the anionic agents behave only as lytic agents. In contrast to this, the anionic agents behave as both flocculants and lytic agents at pH 4.0, whereas the cationic agents act only as lytic agents. The nonionic agent has no significant effect. The mechanisms of flocculation and lysis of chloroplasts are briefly discussed.

Coagulation of ferric oxide sol by organic solvents

SummaryThe coagulation of ferric oxide sol by several organic solvents, such as ethyl alcohol, has been studied. It has been observed that the coagulation takes place when the dielectric constant of medium is lowered to a certain critical value for coagulation by the addition of any organic solvent. The lowering of dielectric constant of medium is accompanied by the contraction of electrical double layer around sol particle, which leads to coagulation.ZusammenfassungKoagulation eines Ferrioxidsols durch verschiedene organische Lösungsmittel findet statt, wenn die Dielektrizitätskonstante bis auf einen „kritischen” Wert durch Zufügung irgendeines organischen Lösungsmittels vermindert wird. Die Erniedrigung der DK des Mediums bedingt die Kontraktion der elektrischen Doppelschichten der Solpartikel, so daß Koagulation erfolgt.

Influence of alcohols upon the action of dodecyl sulfate ions on ferric oxide sol

SummaryThe influence of alcohols upon the action of dodecyl sulfate ions on positive ferric oxide sol has been studied. It is observed that the alcohols promote or prevent both of the coagulation and the dispersion of sol by C12H25OSO3−, according as their concentration is low or high.ZusammenfassungEs wurde der Einfluß von Alkoholen für die Einwirkung von Dodecylsulfationen auf positives Ferrioxidsol untersucht und beobachtet, daß Alkohole Koagulation und Dispersion des Sols durch C12H25OSO3− fördern oder hemmen, je nachdem ihre Konzentration gering oder groß ist.