DIVISION OF THE MATHESON COMPANY. INC. - Analytical

May 16, 2012 - DIVISION OF THE MATHESON COMPANY. INC. Anal. Chem. , 1956, 28 (12), pp 14A–14A. DOI: 10.1021/ac60120a714. Publication Date: ...
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400-ml and ion exchange) accounted for a b o u t three o u t of five separations. T h i s represents a doubling over t h e corresponding 1946 figures, although t h e t a b u lations for t h e two years are n o t entirely comparable.

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Adsorption Chromatographic Ion exchange Extraction Precipitation Distillation Dialysis Other 6

% of Total 19466 1955* 57.0

28.6

17.9 16.9 5.2 3.0

18.4 18.0 10.3 0.9 23.9

45 3 11 7

" Based on 402 entries. ' Includes several topics which were not separation methods, so direct comparisons are not very exact.

Summary About one in 14 papers currently being abstracted in Chemical Abstracts falls within the subject m a t t e r of analytical chemistry; in 1946 the figure was one in 26. T h e United States is leading, as it was in 1946, with respect to t h e a m o u n t of work done in this field. T h e increase in some other countries since 1946, however, has been substantial, so t h a t t h e U. S. now accounts for 2 3 . 8 % compared to 4 1 . 6 % in 1946. I n 1955, t h e leaders, following the U . S., were J a p a n , Germany, Russia, and Great Britain. I n 1946 the leaders were, after t h e U . S., G r e a t Britain, Russia, France, and Sweden. T h e most widely used languages were English, German, Russian, a n d French; in 1946 the order was English, Russian, French, a n d Spanish. T h e ratio of organic to inorganic is approximately equal now, compared to 5 8 % of organic versus 4 2 % inorganic in 1946. T h e analytical method most used both in 1955 a n d 1946 was t i t r i m e t r y (visual and instrumental), with colorimetry (visual and photoelectric), second. A close third place in 1955 was held by t h e various forms of spectrophotometry. In fourth and fifth places in 1955 were gravimetric methods a n d polarography. I n 1946, gravimetric methods held third place. Spectrophotometry and emission spectroscopy held fourth a n d fifth place a decade ago. Among t h e types of preliminary separation, t h e leader in 1955 a n d 1946 was adsorption. T h e 1955 figure (57%) was, however, greater t h a n t h a t in 1946. Second and t h i r d places in b o t h years were t h e same—namely, extraction a n d precipitation.

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