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1. |
PRODUCTION AND PROPERTIES OF 2,3-BUTANEDIOL: XXVII. CRYSTALLINE ESTERS SUITABLE FOR IDENTIFICATION AND ESTIMATION OF THE ISOMERIC 2,3-BUTANEDIOLS |
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Canadian Journal of Research,
Volume 26b,
Issue 11,
1948,
Page 737-746
Florence M. Robertson,
A. C. Neish,
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摘要:
The monoacid phthalates, di-p-nitrobenzoates, di-m-nitrobenzoates, di-3,5-dinitrobenzoates, di-p-bromobenzoates, and di-p-methoxybenzoates oflevo-, andmeso- anddl-2,3-butanediol were prepared to find which derivatives had the best properties for the identification of 2,3-butanediol isomers in a mixture. These are new compounds with the exception of thelevo- anddl-monoacid phthalates and themeso-di-p-bromobenzoate. A procedure is given by which the optical isomers present in a 1 gm. sample of 2,3-butanediol can be identified, and the relative amounts of each estimated. They are converted to the di-p-nitrobenzoates, dissolved in chloroform, polarized to determine the concentration of the optically active isomers, and then fractionally crystallized for identification and estimation of relative amounts of thedl- andmeso-esters.
ISSN:1923-4287
DOI:10.1139/cjr48b-077
出版商:NRC Research Press
年代:1948
数据来源: NRC
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2. |
AN INVESTIGATION OF THE HYDRATES OF CALCIUM SULPHITE |
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Canadian Journal of Research,
Volume 26b,
Issue 11,
1948,
Page 747-751
F. W. Matthews,
A. O. McIntosh,
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摘要:
Numerous references are found to the dihydrate of calcium sulphite, first reported by Muspratt in 1844. Repetition of this work showed no evidence of the formation of a dihydrate at room temperature but rather a hemihydrate. The optical properties reported for the dihydrate were those of the hemihydrate. The X-ray diffraction powder data reported for the anhydrous salt were found to check those of the hemihydrate. The hemihydrate was found to be stable to heating at 250 °C. The dehydration to the anhydrous salt was accomplished by heating in a vacuum at 300 °C.
ISSN:1923-4287
DOI:10.1139/cjr48b-078
出版商:NRC Research Press
年代:1948
数据来源: NRC
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3. |
PHYSICAL PROPERTIES OF POLY-l,2-DIMETHYLETHYLENE PHTHALATE |
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Canadian Journal of Research,
Volume 26b,
Issue 11,
1948,
Page 752-762
R. W. Watson,
N. H. Grace,
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摘要:
The polyester derived fromlevo-2,3-butanediol ando-phthalic anhydride is moderately hard at a number average molecular weight of 660 (DP = 3), and at an averageDPof 4 is a brittle glass. Its hardness on the Brinell scale ranges from about 10 at, to 22–23 at, where it equals the hardness of Lucite. Water absorption decreases with increasing molecular weight, and reaches a value of 0.08% in 430 days at 25 °C. for aDP36 resin. A 50% solution of a solidDP4 resinin acetone has an absolute viscosity at 25 °C. of 1.4 centipoises. Apparently molecular solutions are formed in common aromatic hydrocarbons, ketones, alkyl acetates, alcohols, ethers, and chlorinated solvents.
ISSN:1923-4287
DOI:10.1139/cjr48b-079
出版商:NRC Research Press
年代:1948
数据来源: NRC
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4. |
Note on the Hydrogenation of α-Methylnaphthalene |
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Canadian Journal of Research,
Volume 26b,
Issue 11,
1948,
Page 763-765
H. Shanfield,
E. A. Smith,
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PDF (134KB)
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摘要:
not available
ISSN:1923-4287
DOI:10.1139/cjr48b-080
出版商:NRC Research Press
年代:1948
数据来源: NRC
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