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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.

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.

Cernik, A. A. (1974). British Journal of Industrial Medicine, 31, 239-244. Determination of blood lead using a 4·0 mm paper punched disc carbon sampling cup technique. The method described is designed to overcome difficulties associated with presentation of the sample and its analysis for lead in blood. Chromium-51 studies on the effect of spread showed that imprecision resulted when discs of less than 4·0 mm diameter were punched from a given blood spot. The best standard deviation and relative standard deviation for increasing lead concentrations was obtained when 4·0 mm discs were used. Small daily voltage variations to the carbon cup workhead required that the non-specific absorption should be controlled to 0·02 absorbance at the ashing step. The occurrence of a second non-atomic signal was not considered significant since it had a different volatilization temperature to lead. Several advantages of the method are stated. A comparison of 4·0 mm against 6·5 mm punched discs was investigated using 33 samples of blood ranging from 9·0 to 126 μg of lead per 100 ml blood. Correlation (r = 0·970) and regression lines are shown. Absolute sensitivity of the method was 25 × 10-12 g.

The surfaces of 18-8 stainless steel electropolished or abraded by emery papers have been examined by means of an Auger electron spectrometer. The main results obtained are as follows ;(1) For the electropolished surface and the abraded one, peaks from chrome and nickel are not observed until the surfaces are sputtered with argon ions. The peak heights of carbon and oxygen are decreased, and those of iron, chrome and nickel are increased by ion bombardment.(2) Residuals of electrolytes are observed on the electropolished surface, but abrasives (mainly Al2O3) are not detectable on the abraded one.(3) The results obtained after successive ion bombardment show that the superficial region of the electropolished surface includes much amount of elemental oxygen than the region of the abraded one.

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