Hydrogen residual resistivity

The temperature and thickness dependence of the electric resistivity of Sm, Dy and Tm thin films (25-370 nm thick) was measured between 4.2 and 300 K by Dudas and Feher (1984, 1987), Dudas et al. (1985, 1986, 1987a-d, 1990), and Janos et al. (1987). For Dy films the Neel temperature and the residual resistivity ratio increase both as thickness increases. The thickness dependence of the spin-disorder resistivity is reported in fig. 6. In the case of Tm samples it is observed that the Neel temperature increases (from 49 to 54 K) and in-disorder resistivity decreases (from 35 to lOpQm) as thickness increases (fig. 7). Such results, and correlations with the crystalline orientations (basal plane of crystallites parallel or perpendicular to the substrate surface) correct the errors made by other investigators (see Gasgnier 1980). On the other hand the resistance ratio as a fimction of the temperature exhibits different kinds of curves as the thickness varies as measured for Tm films (fig. 8). Different magnetic transitions have been also observed. One can conclude that numerous kinds of anomalies were caused by hydrogen in solution in the metallic matric, in agreement with Dudas (1991), and also by structure... 

Analyses were performed on each of the resist components to determine the source of the background acid. Background acid was present in all three resist components — polymer, sulfonium salt, and casting solvent. However the sulfonium salt contained the highest concentration of acid by two orders of magnitude. Residual acid in sulfonium salt may be due to the method of preparation which involves an aqueous metathesis step to exchange the hexafluoroantimonate ion for bisulfate. This procedure is likely to produce hydrogen fluoride due to hydrolysis of hexafluoroantimonate salt (14). 

Native monellin consists of two polypeptide chains, a 45-residue A-chain and a 50-residue B-chain, linked by non-covalent interactions. At neutral pH, it is fairly resistant to heat denaturation with a higher than 80 °C. The crystal structure of native monellin shows a tertiary structure comprising an anti-parallel /1-sheet with five strands and an a-helix. H NMR spectroscopy and hydrogen exchange methods have been used to characterize the alcohol-denaturated state of monellin in order to understand how its secondary structure depends on environmental conditions. " Structural and dynamic studies by NMR have been carried out in order to compare native monellin and a non-sweet analogue in which Asp was replaced by Abu . The three-dimensional structures of the two proteins are found to be very... 

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