Methyl polysiloxane (SO) is frequently added to frying oils to inhibit for this thermal deterioration (oxidative polymerization). However, the mechanism remains unclear. Possibly SO forms a protective film on the oil-air interface to prevent oxygen from entering the oil. Though supported by many workers, this view is still only speculation. To confirm whether SO actually forms such a protective film, the following experiments were carried out. 1) The attenuated total reflection (ATR) spectrum in the infrared area of tung oil differed somewhat from that of SO. The difference spectrum in the infrared area for this oil with and without SO clearly showed absorption attributable to SO, thus confirming the presence of SO at the oil-lithium fluoride interface. 2) The photoacoustic spectrum (PAS) in UV region of tung oil differed completely from that of SO. Tung oil had strong absorption at 270280 nm and SO, none in the UV region. If the difference in peak heights at the absortption maximum in PAS for tung oil with SO and without SO may be assumed attributable to the existence of SO, the SO content on the surface of tung oil can be calculated from the ratio of the peak height of tung oil with SO to that without SO. The surface concentration of SO was found several ten times its bulk concentration. The present results demonstrate SO to be concentrated both on the oil-air interface and in oil-vessel interface.
Long N-acylamino acids from various amino acids and dipeptides were examined as carriers for the passive and active transport of alkali (M+), alkaline earth (M2+), and heavy metal cations through a chloroform membrane. Some of the acids more effectively mediated the transport of M+ and M2+ than higher alkanoic acids. Transport efficiency depended greatly on the kind of cation and introduced amino acid residue in the following manner : alanine and phenylalanine were effective for both M+- and M2+-transport and glycylglycine and alanylalanine, for M+-transport. Derivatives of sarcosine and glycine were found quite useful as carriers for the selective transport of heavy metal cations.
By polarized and fluorescent microscopy and TEM, the octyl-and heptylamine salts of both spiculisporic acid (4, 5-dicarboxy-4-pentadecanolide, S-acid) produced by Penicillium spiculisporum and its open-ring acid (3-hydroxy-1, 3, 4-tetradecanetricarboxylic acid. O-acid) were confirmed to form vesicles in water at about pH 6.0, lipid particles at pH 6.36.6 and micelles at about pH 7.0. It showed be pointed out that these alkylamine salts of S-acid and O-acid reversibly change their conversion equilibria among their molecular aggregates within considerably narrow pH differences. Also, these salts correspond to polyalkyl amphiphiles introduced by ionic bonding and thus may possibly adapt themselves to the conversion of their aggregating comformation. In fact, it was found that the chemically modified polyalkyl derivatives of O-acid and agaricic acid (produced by Polyporous officinalis) each having one more alkyl chain formed only vesicles as molecular aggregates. This pH-sensitive or pH-detecting conversion may possibly find use in sensing and separating systems.
A method for the separation of the components of a nonionic mixtures by adsorption column chromatography was developed. Some silica gels for size exclusion chromatography showed characteristic features when applied to adsorption chromatography. They hold high polar components very weakly and release them quite easily, thus making good recovery possible. Resolution, however, was not sufficient from a practical standpoint. A new separation system for nonionic mixtures was developed using two columns, one packed with Fractosil 1000 (silica gel for size exclusion chromatography; Merck) and the other with Silica Gel 60 (for adsorption chromatography; Merck). A mixture containing non-polar to very high polar components such as PEG # 6000 could be separated with good resolution and recovered quantitatively using 7 eluents, selected so as to optimize the system. Switching the column-connection order corresponding to the eluents also ensured good results. Furthermore, an automatic separator was constructed for rapidly separating nonionic mixture. Typical components separation could be achieved automatically, in 4.5 hours, by this separator, whereas a conventional method, for example, that proposed by Newburger et al., requires more than ten hours to complete the same separation.
The dispersing behavior of (W/O) -droplets in a (W/O) /W emulsion was observed. The transient features of both diameter distribution and mean diameter of the (W/O) -droplets were measured until dynamic equilibrium of the dispersion was attained. The following basic information, requisite for quantitatively clarifying dispersing behavior, was obtained. The distribution of (W/O) -droplet diameter was lognormal and the mean diameter decreased exponentially. The (W/O) -droplets coaleased with and then broke up. The mean diameter of (W/O) -droplet was found to be proportional to the -0.65 th power of the Weber number.
Synthesis was carried out of (Z) -and (E) -3, 3-dimethyl-1-cyclohexane acetoaldehyde, (11) and (12), sex pheromones of the cotton boll weevil (Anthonomus grandis Boheman), and a related compound, (Z) -3, 3-dimethyl-1-cyclohexane ethanol (9). The starting material, geraniolene, (1) was converted by a series of relatively simply steps such as acid-catalyzed cyclization, selenium oxidation and hydrogenation into sex pheromones (9), (11) and (12) in yields from 27 to 32%.