CYCLIZATION OF VITAMIN A2
نویسندگان
چکیده
منابع مشابه
Xxi. the Distribution of Vitamin a and Factor A2. I
THE present paper is the full account of work briefly reported elsewhere [Lovern et al. 1937; Edisbury et at. 1937]. The main experimental result is that fish viscera, and notably the pyloric caeca and intestines, are often very rich in vitamin A. Large deposits of vitamin in the absorptive parts of the alimentary tract make it necessary to study the possibility that vitamin A plays an essentia...
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متن کاملthe cyclization of natural rubber
the effects of solvent, temperature, time, weight percent of catalyst on the rate and mechanism of cyclization of natural rubber (nr) was studied in toluene and xylene solutions having tin tetra chloride catalyst (sncl4). iodometric titration show, with 8% sncl4 (based on polymer weight) cyclization occurs, leaving 27.4% of the total unsaturation. infrared spectra of cyclized nr show decreased ...
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ژورنال
عنوان ژورنال: Journal of Biological Chemistry
سال: 1940
ISSN: 0021-9258
DOI: 10.1016/s0021-9258(19)56209-3