Hajime Takayama

Dynamical Properties of Quasi-One-Dimensional Conductors: A Phase Hamiltonian Approach

Since the realization of quasi-one-dimensional conductors, there have been extensive investigations into the electronic properties of other such low-dimensional systems, both experimentally and theoretically [1–4]. Above all, systems having a Peierls transition [5] have been investigated in detail. The novelty of this Peierls—Frohlich (PF) [6] state lies in the novel possibility of the transport phenomenon being associated with the collective degree of freedom, i.e. the charge density wave (CDW) [7]. In a CDW, electrons follow the periodic lattice distortion adiabatically, resulting in a periodic spatial variation of the self-consistent charge density. Lee, Rice and Anderson [8] have shown that the low-lying excitation of CDW is due to the sliding motion associated with the lattice distortion, which is described by the phase of the complex order parameter, i.e. the periodic lattice distortion. This phase is related to the choice of the origin of coordinates and then to the translational symmetry of the system. Hence this sliding motion, or sliding conductivity, is sensitive to the impurity scattering and the Umklapp scattering [8]. These scattering mechanisms result in impurity and commensurability pinning, respectively, whose various interesting properties have been revealed since that time. In these investigations the phase Hamiltonian, which is the effective Hamiltonian to describe the motion of the phase and is derived from the full Hamiltonian with electron-phonon interactions, has proved very useful [8–12]. Recently anomalous properties typically observed in NbSe3 have also been discussed in a similar context [13, 14] and by Monceau in Part II of this volume.

Electrophoretic isolation of a membrane-bound NADPH oxidase from guinea-pig polymorphonuclear leukocytes

Electrophoretic isolation of a membrane-bound NADPH oxidase of guinea-pig polymorphonuclear leukocytes was attempted with the O2- -generating membranes of cells unstimulated or stimulated with C3b-zymosan or sodium dodecyl sulfate, and also with the phagosomes isolated from the phorbol myristate acetate-coated latex particle-phagocytosing cells. When these vesicles were subjected to discontinuous polyacrylamide gel electrophoresis in the presence of Triton X-100 and then assayed for NADPH-Nitroblue tetrazolium reducing activity, the activity was detected by the appearance of a single, blue band of the reduced dye on the gel, independent of the source of vesicles. In addition, the enzyme was able to generate O2- and its activity was significantly augmented with the homologous liver microsomal cytochrome b5. Its activity was heat-labile and inactivated by N-ethylmaleimide and p-chloromercuribenzene sulfonate. The enzyme, with an apparent molecular weight of 150 000, in the phagosomes was easily susceptible to limited proteolysis by trypsin and formed an active fragment with a molecular weight of 70 000, accompanying the loss of O2- -generating activity of the vesicles.

On thed-electron surface density of states of transition metals

Using the moment method and the continued fraction expansion for the one-particle Greens function we have studied thed-electron surface density of states for a transition metal. Besides the reduction of nearest neighbours for a surface atom compared to a bulk atom we have also taken into account the effect that the atomic environment of a surface atom is quite different from that of a bulk atom. This leads to important modifications in the surface density of states which can effect e.g. magnetic surface properties.