The state analysis of NaCl in snow crab (Chionoecetes japonicus) meat examined by 23Na and 35Cl nuclear magnetic resonance (NMR) spectroscopy

To assess the contribution of NaCl to seafood tastiness, ²³Na and ³⁵Cl nuclear magnetic resonance (NMR) spectroscopy was used to determine the mobility of sodium and chloride ions in intact snow crab (Chionoecetes japonicus) leg meat. The T₁ (longitudinal relaxation time) values of both ²³Na and ³⁵Cl, obtained from inverse recovery experiments, show an evident variance with different heat‐processing methods. Heating tends to inhibit both sodium and chloride ion mobility. ³⁵Cl NMR spectra indicate that chloride exists in two different chemical states, one derived from free ions and the other from organic base complexes. © 2000 Society of Chemical Industry     

Electrochemical characterization of the electrical deposition of Co and properties of deposited films using amorphous ribbons as substrate

Both nonelectrically deposited Co‐P and Co‐Fe‐B and electrically deposited Co films were prepared on rapid‐quenched amorphous alloy ribbons. These Co‐based alloy deposits exhibited characteristic polycrystalline structures, surface morphology, and magnetic properties, which were dependent on the species of the amorphous substrates. The electrochemical polarization measurements of substrate electrodes revealed that the electrocatalysis of substrates (e.g., for the anodic oxidation of reducing agent) thoroughly interpreted the deposition potential and the rate of nonelectrical deposition, and the overpotential of electrical deposition were dependent on alloy element of substrate. These electrochemical parameters influence the initial step of deposition, and hence determine the structural and magnetic properties of the deposits obtained. Furthermore, a basic study of the electrical deposition processes on an amorphous ribbon substrate has been carried out in connection with the structural and magnetic properties of the deposits. © 2000 Scripta Technica, Electr Eng Jpn, 130(4): 17–25, 2000     

Effect of Austenite Pre-deformation on Isothermal Martensite Transformation in an Fe-20.5Ni-4.8Mn Alloy

With electron microscopy the investigation on isothermal martensite transformation in an Fe20.5Ni-4.8Mn alloy has been carried out to clarify the effect of austenite state on the transformation, by applying pre-deformation to austenite before isothermal holding. Under the condition without pre-deformation, the isothermal martensite products are lath martensite with {111}fhabit planes. Dislocations in austenite seem to contribute to nucleation of martensite, and in this nascent Stage austenite substructure has no obvious effect on martensite growth. The consequent thickening of martensite laths is apparently influenced by local austenite states, resulting in the changes in orientation, morphology as well as substructure of martensite lath. The kinetics of isothermal martensite transformation is controlled by intedece dislocation determined nucleation of martensite in primary stage, but to a larger extent, by the austenite accommodation for the shape strain of martensite in the thickening Stage     

Oxidation‐reduction equilibria of ferrous/ferric ions in oxide melts

Oxidation‐reduction equilibrium experiments were conducted with oxide melts containing CaO, Li₂O, Al₂O₃, ZnO, B₂O₃, SiO₂ and small concentrations of iron oxide. The results indicated that for compositions within the acidic regime, the ratio {(Fe³⁺)/(Fe²⁺) P_O2^1/4} decreased with an increase in basicity while for relatively basic melts, the ratio increased with an increase in basicity. This variation of {(Fe³⁺)/(Fe²⁺) P_O2^1/4} could be interpreted in terms of the optical basicity of the glass melts and is consistent with the following expressions for the red‐ox equilibria within acidic and relatively basic melts, respectively: In an acidic melt, the temperature dependence of the reaction yielded an enthalpy value which was in excellent agreement with the enthalpy change for the reaction: For a relatively basic melt, the enthalpy value for the corresponding reaction was about half of that found for the acidic melt.     

Preparation of nitrogen-doped porous carbon by ammonia gas treatment and the effects of N-doping on water adsorption

Nitrogen-doped porous carbons (N-RFCC) were prepared by NH₃N₂ mixture gas treatment at high temperature during the carbonization process on resorcinol–formaldehyde cryogels. To show the role of N-doping on the adsorption behavior we carried out water adsorption, and it was found that the amount of water adsorbed is directly related to the nitrogen content over the low pressure region (P/P₀ < 0.3). Applying the theoretical water adsorption model, Horikawa–Do (HD) model, to the adsorption isotherms of N-RFCCs, we could analyze the effects of nitrogen-doping on the adsorption mechanism. Although the concentration of functional groups of N-RFCC is almost equal to that of the non-doped RFCC, which was measured by Boehm titration method, the water adsorbed amounts of N-RFCCs over the low pressure region were larger. This is due to part of the doped nitrogen atoms act as functional groups, contributing to the total concentration of functional groups. The saturated concentrations depend on the packing fraction of water molecules, which in turn depends on the pore size. The packing fractions of N-RFCCs are larger than those of RFCCs, and this could be attributed to the high affinity between water clusters and N-doped surfaces, resulting in a reduced hydrophobicity of the surface.