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Electron microscopic studies were carried out with regard to the effects of the filling, the internal sizing and the surface sizing on the surface fine structures of uncoated papers. Results were summerized as follows : (1) Direct carbon reprica technique was found to be available especially for observing filler distribution on uocoated paper surfaces. (2) By observing commercial uncoated paper surfaces by the transmission and scanning electron microscopy, it was found that the wire side showed a greater filler loss than the top side. (3) The two sideness of filler retention was found to depend on the methods of sheet formation. In hand made sheet, the wire side had higher filler retention than the top side. On the paper made by the miniature fourdrinier paper machine, the two sideness of filler retention was almost eliminated. On the paper made by the commercial fourdrinier paper machine, the filler retention of the wire side was conspicuously lower than the top side. (4) Two sideness of the filler retention of commercial papers was found to be increased as the filler content increased. (5) In the surface sizing, surface of the fibers were found to be covered with an amorphous film of a sizing agent in proportion to the degree of sizing.

This paper describes the method for the separation and identification of zinc dithiophosphates having alkyl or aryl substituents by partition paper chromatography.Of a variety of solvent systems examined, the solvent system of cresyldiphenyl phosphate (stationary phase)-90/10 isooctane•n-cetane (mobile phase) was most suitable for the separation and identification of zinc dialkyldithiophosphates. Their Rf values with this solvent system increase with the number of carbon atoms in the alkyl group. Among zinc dialkyldithiophosphates having isomeric alkyl groups respectively of straight primary, branched primary and secondary, the Rf values increase in this order. The solvent system of liquid paraffin-isopropyl alcohol was found to be satisfactory for partition paper chromatography of zinc dialkyldithiophosphates having long chain alkyl groups.A large difference in the Rf values between zinc dialkyldithiophosphates having isomeric alkyl groups respectively of primary and secondary, was observed when the solvent system of polyoxyethylene octylphenylether (E. O. 10mol)-n-heptane was used and similarly, a large difference in the Rf values between zinc dialkyldithiophosphates having isomeric alkyl groups respectively of straight primary and branched primary, was observed when the solvent system of chlorinated paraffin-isopropyl alcohol was used. It is effective especially for the analysis of mixtures of zinc dialkyldithiophosphates to use these solvent systems together with the solvent system of cresyldiphenyl phosphate-90/10 isooctane•n-cetane.It was found that zinc diaryldithiophosphates can be distinguished from zinc dialkyldithiophosphates by the solvent system of chlorinated paraffin-isopropyl alcohol and identified by the solvent system of cresyldiphenyl phosphate-90/10 isooctane•n-cetane or liquid paraffin-isopropyl alcohol.Zinc dithiophosphates in commercial antioxidants and EP hydraulic oils could be identified by the above mentioned solvent systems.

A new technique for measuring peak pressures of repeated high amplitude sound pulses in liquids is described. The method involves the transfer of carbon from carbon paper to white `printing-out paper' as a result of the pressure exerted by a pulse. The darkening produced on the white paper was estimated photometrically and used as a measure of the peak pressure in the pulse. Using this procedure, measurements were made in a water column of pulse peak pressures up to 700 atm.

Using C/sup 14/ samples absorbed on thin paper discs, the apparent radioactivity of samples of glycine and hemin was measured in a gas-flow counter over a wide range of specimen thickess. Results show that specimens ranging up to a thickness of 150 mu g/cm/sup 2/ may be regarded as approximately infinitely thin. It is estimated that the count rate is decreased by approximately 20% as a result of absorption of the radioactivity by the paper. To a considerable extent, the change in count rate due to self-absorption varies as the reciprocal of a linear function of the thickness of both the paper and the specimen. (auth)

The isolation of mono- and di-n-butylphosphoric acids from commercially available mixtures has been examined. A simple solvent extraction method based on the distribution of the acids between carbon tetrachloride-water, and diethylether-water, mixtures has been developed to obtain the individual acids with < 1 per cent of total (< 0·5 per cent acidic) impurities. A rapid paper chromatographic method of analysis is described which uses upward elution with a basic solvent mixture. The separated acids are then detected by spray reagents and the method allows approximately 0·5% v/v of each acid to be estimated visually in the presence of the other.

The authors studied the use of chloranilic acid for the localization of sodium salts of organic acids separated by paper chromatography. Besides avoiding “tailing” of the spots and loss by volatilization of the lower members of the series, the use of sodium salts permits a very high sensitivity, as amounts as low as 0.2 μg of sodium are detectable. Sensitivity in relation to the acids was found to be proportional to the number of neutralized carboxyls and inversely proportional to the number of carbon atoms in the molecule. In the case of nitrogen-containing organic acids the sensitivity was higher than that expected, because chloranilic acid reacts with the N atom.

The chromatographic and chromogenic behavior of 76 nitrogen and carbon substituted hydroxy-, 2-hydroxyethyl-, 2-chloroethyl derivatives and related compounds toward 19 detecting reagents and three solvent systems is described.

Separation of simple saturated hydroxamic acids with a chain length of one to nine carbon atoms has been achieved by partition chromatography on paper. The relative merits of a number of solvents are discussed.

THE work of Martin and Synge1 on the separation of amino-acids by partition chromatography on silica gel has led to the application of this method to the separation of other groups of structurally similar compounds. Lester Smith2 and Ramsey and Patterson3,4 have separated by this means the straight-chain fatty acids containing one to ten carbon atoms, and Elsden5 has put the procedure on a quantitative basis in the case of acetic, propionic and n-butyric acids.

IODINE has been used as a colour reagent for paper chromatography of amino-acids and their derivatives1,2, imidazoles3, and other nitrogen-containing compounds1,4. Steroids are also revealed by this technique, which is sufficiently sensitive to enable location of 0.5 µgm. œstrone5. The method has not gained wide acceptance possibly only because it cannot be relied on to yield a colour diagnostic of a class of compounds—some nitrogen-containing compounds are not revealed—but its application is simple, and if unsuccessful, other colour reagents can be applied to the same chromatogram. In the most convenient procedure, the dried paper is exposed to iodine vapour (supplied by a few iodine crystals in a closed battery jar) for 10–30 sec.; or the paper may be sprayed with a solution of iodine in carbon tetrachloride3, or may be dipped into a saturated solution of iodine in petroleum ether (b.p. 60°–80°)5. Compounds are revealed usually as brown spots, which fade rapidly.