摘要:

Horse globin had been shown previously to dissociate into four subunits by suitable adjustment of pH and ionic strength. Two components have been separated electrophoretically. One of these separated components associates readily as pH and ionic strength are varied. The second component shows little tendency to associate with itself. The behavior of unfractionated globin indicates that interactions occur between these two components.

ISSN:0008-4042    

DOI:10.1139/v57-129

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

A synthesis of 5,6-dideoxy-D-xylohexose (I) fromD-glucose is described. The action of sodium iodide in acetone on some toluene-p-sulphonyl esters of sugar derivatives is detailed.

ISSN:0008-4042    

DOI:10.1139/v57-130

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

When a suspension of cellulose, or a solution of starch, in 17.8% aqueous sodium hydroxide was shaken with a large excess of carbon disulphide, a sodium xanthate of degree of substitution (D.S.) about 0.4 was obtained. The replacement of the sodium hydroxide by 17.8% potassium hydroxide resulted in a product of D.S. about 1.3. Plots were made of the D.S. of cellulose xanthate resulting from the use of various concentrations of the hydroxides of lithium, sodium, potassium, rubidium, and cesium; the plots for the last three hydroxides were similar, and differed sharply in form from those of the first two.Potassium cellulose or starch xanthate of D.S. about unity was freely soluble in water as well as in aqueous alkalies and the solutions "ripened". When immersed in methyl iodide, the dry salts yielded the correspondingS-methyl xanthates without change in the D.S. TheseS-methyl xanthates were white substances insoluble in water but dissolved or dispersed by carbon disulphide. They could be acetylated with sulphuric acid as catalyst and without change in theS-methyl xanthate D.S. The acetylated cellulose derivative was freely dispersed by chloroform or trichloroethylene.

ISSN:0008-4042    

DOI:10.1139/v57-131

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

The Raman spectra of liquid (CD3)3CH and (CD3)3CD were obtained photoelectrically together with depolarization ratios, and the infrared spectra of the corresponding gases were obtained from 3 to 35 μ. A vibrational assignment consistent with depolarization ratios and band contours has been made for the molecules on the basis ofC3vsymmetry. The spectra have been correlated with the spectra of (CH3)3CH and (CH3)3CD and modified assignments for two modes have been given for these molecules. Tentative assignments have been made for the 'inactive'A2modes (which are 'active' if the molecule has symmetryC3) to explain some of the observed frequencies around 1000 cm.−1which could not be satisfactorily assigned as summation or difference tones.

ISSN:0008-4042    

DOI:10.1139/v57-132

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

Quantitative ion exchange and 4π counting techniques have been used to measure the yields of four nuclides not previously determined by mass spectrometric analysis. Values of 6.57, 6.30, 4.74, and 5.71% were obtained respectively for Ba139, La141, Sr89, and Sr91relative to a value of 6.32% for the yield of Ba140. A precision better than 1.3% was achieved in the measurements.

ISSN:0008-4042    

DOI:10.1139/v57-133

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

Specific conductivities of aqueous solutions of sodium dodecyl sulphate, sodium decyl sulphate, and sodium octyl sulphate were measured over concentration ranges about the respective CMCs and at temperatures from 10° to 55 °C. Values of the increase in heat content associated with micelle formation are estimated from the temperature variation of the CMC and the relation of these results to the theory of micelle formation is considered.

ISSN:0008-4042    

DOI:10.1139/v57-134

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

Deacetylation of crystalline tri-O-trityl-penta-O-acetyl sucrose gave an amorphous tri-O-trityl sucrose derivative and methylation of this product followed by graded hydrolysis with acetic acid yielded a sirupy penta-O-methyl sucrose. Hydrolytic cleavage of the penta-O-methyl sucrose to nearly equal amounts of 2,3,4-tri-O-methyl-D-glucose and 3,4-di-O-methyl-D-fructose established the original positions of theO-trityl groups at the primary carbons in the sucrose molecule. It was therefore evident that acetyl migration from C4to C6in the glucose moiety had occurred during an earlier synthesis of 1′,4,6′-tri-O-methyl sucrose from the tri-O-trityl-penta-O-acetyl sucrose. The probable conformation of the transition state in the acyl migration is discussed.

ISSN:0008-4042    

DOI:10.1139/v57-135

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

The variation of the photocurrent with temperature is found to obey the relationi = i0e−E/RTin naphthalene, stilbene, diphenyl, terphenyl, β-methylanthracene, anthracene, azulene, and pyrene. The activation energies have been measured and are found to increase in the above order. These activation energies show no apparent correlation with the corresponding activation energy of semiconduction, and it is suggested they are associated with the charge carrier transport process.

ISSN:0008-4042    

DOI:10.1139/v57-136

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

The absorption spectra of the ferric ion and its first hydrolysis product in an aqueous solution of perchloric acid was determined. The Fe3+ion has two absorption bands, one with a maximum at 240 mμ and another which extends into the region below 200 mμ. The FeOH2+ion also has two absorption bands, the maxima of which occur at 300 mμ and 205 mμ. A figure shows the magnitude of the absorption of each of these ions from 200 to 350 mμ.

ISSN:0008-4042    

DOI:10.1139/v57-137

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

A water soluble arabogalactan isolated from jack pine was shown to have a molar ratio of arabinose to galactose of 1:13, and a number average degree of polymerization of 53 ± 3. Fractionation data and electrophoresis indicated that the arabogalactan was homogeneous. Hydrolysis of the methyl ether of the polysaccharide yielded 2,3,5-tri-O-methyl-L-arabinose (4 moles); 2,3,4,6-tetra-O-methyl-D-galactose (12–13 moles); 2,3,4-tri-O-methyl-D-galactose (19 moles); 2,6-di-O-methyl-D-galactose (1 mole); and 2,4-di-O-methyl-D-galactose (14 moles). Some features of the structure of the arabogalactan are discussed on the basis of these results.

ISSN:0008-4042    

DOI:10.1139/v57-138

出版商:NRC Research Press    

年代:1957

数据来源: NRC