Adiabatic Solid Effect

Silk is blended with wool to make high-class apparel, contributing luster and strength. For the dyeing of silk/wool blends, the solid shades are usually required. However, the apparent color strength of dyed wool is generally higher than that of silk, which must be improved through the selection of dyes employed as well as the control of pH and dyeing temperature. In this paper, a novel approach of syntan application to improving the solid effect of silk/wool blends dyed with acid dyes was investigated. The influence of syntan on the distribution of different acid dyes in silk and wool as well as the apparent color strength of two fibers was determined. The mechanism for syntan to improve the solid effect was discussed according to the behaviors of syntan adsorption on silk and wool as well as fiber structures.

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Three-spin solid effect and the spin diffusion barrier in amorphous solids

Science Advances ◽

10.1126/sciadv.aax2743 ◽

2019 ◽

Vol 5 (7) ◽

pp. eaax2743 ◽

Cited By ~ 10

Author(s):

Kong Ooi Tan ◽

Michael Mardini ◽

Chen Yang ◽

Jan Henrik Ardenkjær-Larsen ◽

Robert G. Griffin

Keyword(s):

Diffusion Barrier ◽

Nuclear Polarization ◽

Spin Diffusion ◽

Amorphous Solids ◽

Second Step ◽

Intimate Contact ◽

Glycerol Water ◽

Water Matrix ◽

Solid Effect ◽

Trityl Radical

Dynamic nuclear polarization (DNP) has evolved as the method of choice to enhance NMR signal intensities and to address a variety of otherwise inaccessible chemical, biological and physical questions. Despite its success, there is no detailed understanding of how the large electron polarization is transferred to the surrounding nuclei or where these nuclei are located relative to the polarizing agent. To address these questions we perform an analysis of the three-spin solid effect, and show that it is exquisitely sensitive to the electron-nuclear distances. We exploit this feature and determine that the size of the spin diffusion barrier surrounding the trityl radical in a glassy glycerol–water matrix is <6 Å, and that the protons involved in the initial transfer step are on the trityl molecule. 1H ENDOR experiments indicate that polarization is then transferred in a second step to glycerol molecules in intimate contact with the trityl.

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Rare spin polarization by the nuclear solid effect

Journal of Magnetic Resonance (1969) ◽

10.1016/0022-2364(86)90257-x ◽

1986 ◽

Vol 68 (2) ◽

pp. 373-376 ◽

Cited By ~ 1

Author(s):

R.A Wind ◽

C.S Yannoni

Keyword(s):

Spin Polarization ◽

Solid Effect

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