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Consden, Gordon and Martin reported a very ingenious method for the separation of amino acids by filter paper chromatography in which phenol or some other appropriate organic solvent sweeps the applied amino acids along the filter paper, capillarity causing the organic solvent to move. The percentage of light intermission along the chromatogram is measured and this transmission has been plotted on semi-log graph paper against the distance along the filter paper strips, and the areas of the segments above the plotted curve measured with a planimeter. It has been found that the areas so determined are over a limited concentration range a simple function of the concentration of the amino acids. The various factors which influence the reliability of this method are reported.

The performance of 4 paper tapes impregnated with silver nitrate, potassium dicyanoarginate (I), mercuric chloride, and lead acetate was assessed in collecting and stabilizing H/sub 2/S for optical densitometric determination to provide a simple, portable, specific, and inexpensive method for unattended laboratory and field determination of H/sub 2/S in air. Results indicate that the silver-nitrate tapes are highly recommended for H/sub 2/S determination in the 0.001--50 ppm. Their main disadvantage, sensitivity to light, is considered very minor. The study indicates that many of the criticisms of the impregnated-tape methods can be attributed to insufficient recognition of the precautions necessary for good quantitative analyses. For example, these precautions for determination of 0.1 ppm H/sub 2/S with silver-nitrate tapes require a less than 60 1/min/sq in. flow rate, protection from light, tape handling at edges only, avoiding temperatures greater than 40/sup 0/C, and avoiding high flow rates at very low humidities (greater than 10 percent RH).

A YEAR ago the authors reported that the paper industry was on its way up from a minor dip that had reached its minimum in July 1952 and that a feeling of optimism for 1953 pervaded the industry. Beginning in April 1953 production ratios attained levels significantly above those of the previous year, and have remained there steadily, as shown by the accompanying graphs. This near-capacity rate was apparently leading to new high production records for the year. For the first three quarters, total production of paper and board amounted to 19,915,000 tons, a 10.6% increase over 1952, and this level was being maintained in the last quarter. Paper was up 3.5% and board 18.4%. There was, of course, considerable variation in different categories. Newsprint was down 6% for the first three quarters, and fine papers down 3%. Tissues and absorbent papers were up 15%, and book papers showed an 11% increase. All types of ...

PROFITABLE work on the development, evaluation, and application of chemicals for the pulp and paper industry can be conducted on either a small or large scale. However, increasing use of a great variety of chemical products has accentuated the trend toward establishment by chemical manufacturers and suppliers of rather large laboratory groups which, whatever their name, generally have as their primary objective the type of work that may be classified a s application research. This would certainly include the search for uses of new or old chemicals that are being or could be manufactured, and the development of suitable procedures for using or applying established or new chemicals. It also might include the development of new or improved products to satisfy the needs of a particular industry. Quite often an application research group will have assigned to it other diverse duties which cannot be classified strictly as application research, but which are related to it. ...

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