Dimensional stability of regenerated cellulose film in relation to orientations of crystalline and noncrystalline phases

The dimensional stability of regenerated cellulose film on swelling with water is discussed in relation to the biaxial orientation of the two kinds of structural units, cellulose II crystallites and noncrystalline chain segments, and their anisotropic swelling (anisotropic absorption of water). Considerable dimensional stability in the plane of the film but enormous instability of thickness on swelling in water of some commercial cellophanes is qualitatively interpreted in terms of the planar orientation of crystal (101) planes along the film surface and the orientation of the noncrystalline chain segments parallel to the film surface. The dimensional changes on swelling from the completely dry state to 10% moisture regain were further interpreted quantitatively in terms of the degrees of biaxial orientation of the two kinds of structural units and their degrees of anisotropic swelling by modifying the Hermans monophase model for crystalline and noncrystalline biphase structures. The following degrees of anisotropic swelling of the structural units were thus obtained: q_{c, [101]} = 0.40%, q_{c, [101 ]} = ?0.33%, and q_a = 2.42%.     

Singlet unrestricted Hartree-Fock Slater (UHFS) model for unstable metalmetal bonds

The electronic properties of weak metalmetal bonds are investigated on the basis of the singlet unrestricted Hartree-Fock Slater (¹UHFS) model. It is pointed out that the ¹UHFS model is sufficiently useful in describing the electron-transfer processes in cluster compounds which are regarded as models of organic semiconducting complexes.     

Spin-symmetry forbidden properties of free-radical cycloadditions

Stabilities of free radicals with linear, Hückel and Möbius Hückel conformations are investigated on the basis of the stability conditions of the RHF solutions. The spin-symmetry forbidden properties of free-radical cycloadditions are discussed in terms of the above stability analyses.     

Spontaneous compactification and CPN: SU(3) × SU(2) × U(1), sin2θW, g3/g2 and SU(3)-triplet chiral fermions in four dimensions

We examine the compactification of D=4+2N, Einstein-Maxwell-Dirac theory. It is shown that the manifold CP_N × M₄ is a solution of the equations of motion. The structure of the fermions, gauge bosons and their couplings in the four-dimensional effective theory is investigated. The scale of CP_N is quantized by a generalized Dirac condition. When the results are applied to the solution with internal space CP₁×CP₂, the weak mixing angle and the ratio of the couplings of SU(3) (g₃) and SU(2) (g₂) are defined by two integers and a hypercharge. An SU(3)-triplet chiral fermion can appear in four-dimensional effective theory.     

Kinetic study of transmembrane electron transport by the hinkle process

Trans-membrane redox reactions mediated by t-amylferrocene (one-electron carrier) were studied kinetically in a liposome system separating two redox pairs (ferricyanide/ferrocyanide and dehydroascorbate/ascorbate). In order to eliminate the membrane potential generated, which suppressed the rate of the reaction, the rate was measured in the presence of carbonylcyanide m-chlorophenylhydrazone. The reaction rate was independent of concentrations of ascorbate and dehydroascorbate. Ferricyanide also had virtually no effect on the rate, but addition of ferrocyanide decreased it. The results were analysed on the basis of rate equations derived from the possible reaction mechanism, and it was concluded that the rate-determining step of the trans-membrane redox reaction was the process of diffusion of the mediator in the membrane.     

Katalysator als ein lyophiles Kolloid

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