STUDY OF SITE GEOMETRY OF THE Sn CATIONS IN THE Sn-ADDED Tl-Pb(1223) SUPERCONDUCTING SYSTEM USING MÖSSBAUER AND AUGER EMISSION TECHNIQUES

The addition of Sn in Tl,Pb(1223) ( Tl 0.5 Pb 0.5 Sn x Sr 1.6 Ca 2.4 Cu 3 O y) has been investigated using AES and Mössbauer Emission techniques to probe the valence and site geometry of Sn cations. It was found that Sn is present in tetravalent state in the compound at two sites with differing weights. The major part of the tin resides inside the grain and a minor part (weak doublet line in Mossbauer spectra) represents the contribution from the tin at the grain boundary.

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Effect of Composition on Shrinkage of Mold Cured Elastomeric Compounds

Rubber Chemistry and Technology ◽

10.5254/1.3535770 ◽

1978 ◽

Vol 51 (5) ◽

pp. 1044-1059 ◽

Cited By ~ 1

Author(s):

J. R. Beatty

Keyword(s):

Major Part ◽

Thermal Coefficient ◽

Thermal Contraction ◽

Volume Percent ◽

Specific Effects ◽

Degree Of Orientation ◽

Minor Part ◽

The Common ◽

A Minor ◽

Soft Rubber

Abstract The mold shrinkage of elastomer compositions depends upon the elastomer employed, the volume percent of elastomer plus all other organic materials, and the kind and amount of pigment present. The specific effects of pigments in inhibiting the shrinkage are shown. A procedure is given by which the shrinkage of most soft rubber compositions of the common elastomers may be calculated from the recipe. The major part of the shrinkage of elastomer compositions is due to the much greater thermal contraction of the composition than that of the mold. This portion of the shrinkage depends upon the thermal coefficient of expansion of the composition and mold and the temperature difference between the curing and room temperatures. A minor part of the shrinkage is due to a contraction in volume resulting from vulcanization. For normal soft rubber stocks with sulfur concentrations of three phr or less and for normal neoprene stocks, this factor may be neglected. For stocks having higher sulfur ratios an allowance needs to be made for this factor. Shrinkage of fiber loaded stocks should be determined carefully depending on the quantity, and particularly on the degree of orientation of the processed stock.

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The difficulty of isolating grain boundary components in the Mössbauer spectra of ball-milled materials: iron and silver–iron alloys

Solid State Communications ◽

10.1016/s0038-1098(02)00161-8 ◽

2002 ◽

Vol 122 (6) ◽

pp. 299-302 ◽

Cited By ~ 14

Author(s):

Georg Rixecker

Keyword(s):

Grain Boundary ◽

Mössbauer Spectra ◽

Iron Alloys ◽

Mossbauer Spectra

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The Shrinkage of Mold Cured Elastomer Compositions

Rubber Chemistry and Technology ◽

10.5254/1.3542868 ◽

1955 ◽

Vol 28 (4) ◽

pp. 1141-1156 ◽

Cited By ~ 2

Author(s):

A. E. Juve ◽

J. R. Beatty

Keyword(s):

Major Part ◽

Room Temperature ◽

Curing Temperature ◽

Mold Material ◽

Thermal Coefficient ◽

Thermal Contraction ◽

Specific Effects ◽

Minor Part ◽

A Minor ◽

Soft Rubber

Abstract The coefficient of expansion of elastomer compositions depends on the kind of polymer employed, the volume per cent of polymer plus all other organic materials, and the kind and the amount of pigment present. The specific effects of pigments in retarding the shrinkage are shown. A procedure is given by which the shrinkage of most soft rubber compositions of the principal rubbers may be calculated from the recipe. The major part of the shrinkage of elastomer compositions is due to the much greater thermal contraction of the composition than of the material from which the mold is made. This portion of the shrinkage depends on the thermal coefficient of expansion of the composition and the mold material and the temperature difference between the curing temperature and room temperature. A minor part of the shrinkage is due to a contraction of volume resulting form vulcanization. For normal soft rubber stocks with sulfur ratios of three parts or less and for normal Neoprene stocks, this factor may be neglected. For stocks having higher sulfur ratios, an allowance needs to be made for this factor.

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New Method for Quantitative Preparation of Lignin- Carbohydrate Complex from Unbleached Softwood Kraft Pulp: Lignin-Polysaccharide Networks I

Holzforschung ◽

10.1515/hf.2003.011 ◽

2003 ◽

Vol 57 (1) ◽

pp. 69-74 ◽

Cited By ~ 41

Author(s):

M. Lawoko ◽

G. Henriksson ◽

G. Gellerstedt

Keyword(s):

Major Part ◽

Kraft Pulp ◽

The Other ◽

Quantitative Yield ◽

New Method ◽

Residual Lignin ◽

Carbohydrate Complex ◽

Softwood Kraft Pulp ◽

Minor Part ◽

A Minor

Summary A new method for the quantitative preparation of pulp representative lignin-carbohydrate complexes (LCC) has been developed, in which LCC has been systematically prepared at quantitative yield, fractionated and qualitatively determined. At least 90% of residual lignin in softwood kraft pulp is proposed to be chemically bonded to carbohydrates. A major part of LCC (92%) in softwood kraft pulp was observed between lignin, xylan and glucomannan, whereas a minor part (8%) was linked to cellulose. Half of the hemicelullosic LCC is a lignin-glucomannan complex. The other half is lignin-xylan complex and xylan-lignin-glucomannan complex. Thus, part of the residual lignin in softwood kraft pulp crosslinks xylan and glucomannan. The proposed linkages are of covalent type. At most 10% of the residual lignin is not bonded covalently to carbohydrates.

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FREE AND PROTEIN-BOUND TRI-IODOTHYRONINE IN THE SERUM OF VITAMIN A-DEFICIENT RATS

Journal of Endocrinology ◽

10.1677/joe.0.0840135 ◽

1980 ◽

Vol 84 (1) ◽

pp. 135-140 ◽

Cited By ~ 10

Author(s):

H. GARCIN ◽

P. HIGUERET

Keyword(s):

Vitamin A ◽

Negative Correlation ◽

Major Part ◽

Serum Vitamin ◽

Serum Samples ◽

Deficient Diet ◽

Serum Free ◽

Positive Correlation ◽

Minor Part ◽

A Minor

Tri-iodothyronine (T3) transport in the serum of rats on a vitamin A-deficient diet was studied by electrophoresis after the incubation of serum samples with radioactive T3. The level of serum free tri-iodothyronine (fT3) was measured by radioimmunoassay after serum chromatography on Sephadex LH-20 gel. In the serum of control rats a major part of the radioactivity was bound to the albumin zone (61%) and a minor part to the prealbumin zone (32%). In the serum of vitamin A-deficient rats a larger amount of radioactivity was bound to the postalbumin zone; the lower the level of vitamin A in serum, the greater was the radioactivity in this zone of the electrophoretogram. In these animals there was also a negative correlation between the serum vitamin A and the fT3. There was also a positive correlation between the radioactivity bound to the postalbumin zone and the fT3. The possible causes and effects of these modifications in vitamin A-deficient rats are discussed.

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