SPECTRAL FORMS AND ORIENTATION OF BACTERIOCHLOROPHYLLS c AND α IN CHLOROSOMES OF THE GREEN PHOTOSYNTHETIC BACTERIUM Chloroflexus aurantiacus

Spectral forms of bacteriochlorophyll (Bchl) in chlorosomes were analyzed by linear dichroism, circular dichroism (CD), and deconvolution of these spectra. Isolated chlorosomes were embedded in polyacrylamide gels and compressed unidirectionally (along the x-axis) while allowing the gel to stretch in another direction (along the z-axis). The chlorosomes were aligned three-dimensionally due to their flat oblong shape; the longest axis was presumed to parallel the z-axis, its shortest axis was presumed to parallel the x-axis, and the intermediate-length axis was presumed to parallel the y-axis. Degrees of polarization (A_I? A₁)/(A_I+ A₁) of Bchl c and a measured from the y-axis with linearly polarized light were significantly different from those measured from the x-axis. Deconvolution of spectra into components revealed the presence of two major forms of Bchl c with peaks at 744 nm and 727 nm. The degrees of polarization of the 744 and 727 nm spectral forms were 0.76 and 0.59 from the y-axis and 0.48 and 0.39 from the x-axis, respectively. The degrees of polarization of Bchl a794 were –0.21 from the y-axis and 0.12 from the x-axis. These values indicate that the direction of the Q_y transition moment of Bchl c744 is almost completely parallel to the longest axis of chlorosomes and that of Bchl c727 is also nearly, but slightly less so, parallel to the longest axis of the chlorosomes. The Q_y transition moment of the baseplate Bchl a peak at 794 nm is nearly perpendicular to the longest axis and parallel to the shortest axis: that is, it is perpendicular to the associated membrane plane in the cell. These alignments of Bchl transition moments in chlorosomes were lost after suspending the chlorosomes in a solution saturated with 1-hexanol accompanying a shift in the peak position from 742 nm to 670 nm. The alignment recovered after the hexanol concentration was decreased. The presence of two major spectral forms of Bchl c was supported by the deconvolution of CD spectra and absorption spectra.     

Spin structure of the nucleon

Based on an infinite sublayer quark model, we determine the fraction of nucleon spin carried by subquarks.     

Some theorems on S3(K metric spaces

The concept of S3-like Finsler space was introduced by M. Matsumoto in 1971 ([4]). The differential equations which are fundamental in the study of S3-like Finsler spaces were given in Theorem 1 in a previous paper ([7]). In the present paper it will be proved that differential equations define S3-like Minkowski spaces (Theorem 2) and yield the special solutions (Lemma 2). From this facts we will get special S3-like Minkowski spaces (Theorem 4).     

Mixed conduction in sodium vanadium bronze

The ionic and electronic conduction in α'-Na_xV₂O₅ prepared by the solid state reaction has been investigated. The electronic conductivity is nearly equal to the total conductivity and depends on the V⁴⁺ ion concentration. The Na⁺ ion conductivity was measured by a dc technique. The building up and decaying curves obtained at the transient polarization phenomena were analyzed by using a certain approximation for the steady state in order to save experimental time. The typical ionic conductivities were relatively low, namely 3×10^?6 and 2×10^?1 S cm?1 at 300°C for the samples of x=1.0 and 0.8, respectively which seemed to be dependent on the number of vacant Na⁺ ion sites.     

Triplet sensitized isomerization of a CCCN system. Energy surface of the triplet state and effects of azulene,oxygen, and di-tert-butyl nitroxide

The photostationary isomer ratios and quantum yields for triplet sensitized isomerization of the four isomers of a conjugated imine, l-methoxyimino-3-phenyl-2-propene, were determined to explore the reaction mechanism.