Fine structure of rainfall

The raindrop size, the raindrop shape, and the raindrop fall velocity measured are shown. It was found that many small raindrops of 50 to 500 μm diameter whose sizes have never been measured, exist in common rainfall. Also the distribution of canting angle of deformed raindrops is measured. For estimating the microwave attenuation due to rainfall, especially that of millimeter waves, a probability distribution function of raindrop size is presented. Finally, it is shown that the raindrop size distribution is not uniquely determined only by rainfall intensity.     

Chemical-bonding structure of InP surface in MOVPE studied by surface photo-absorption

Using surface photo-absorption spectra, we established a phase diagram of the surface chemical-bonding structure for the P-stabilized surface in InP metalorganic vapor phase epitaxy as a function of substrate temperature and PH₃ partial pressure. At 550°C and PH₃ partial pressures of 10 and 30 Pa, the surface is (2 × 4)-like consisting of P dimers having a bond axis parallel to [110]. As the substrate temperature decreases and the PH₃ partial pressure increases, amorphous P species start to adsorb excessively on (2×4)-like P dimer surface. A c(4 × 4)-like surface was not observed. From InP growth experiments for each P surface phase, we found that, to obtain high-quality InP epitaxial layers, excess P adsorption should be suppressed by minimizing the formation of native defects.     

Electronic structure of wurtzite- and zinc blende-GaN studied by angle-resolved photoemission

The valence band structures of both wurtzite- and zinc blende-GaN were investigated by angle-resolved photoemission spectroscopy. It was found the k dispersions of the upper valence bands show band structures corresponding to wurtzite or zinc blende structure. In wurtzite-GaN, band width of the upper valence band is 6.7 eV in good agreement with the theoretically predicted value. However, the binding energy of Ga 3d level was found to be 15.7 eV relative to the valence band maximum, which is about 2 eV higher binding energy than those predicted by local density approximation calculations. In zinc blende-GaN, some discrepancies in the binding energy of the topmost bands around the valence band maximum was observed. We discuss the cause of these discrepancies by taking into account the strain effect.     

The structure of an Al3Pd-based modulated structure studied by atomic-scale electron microscopy observations

A modulated structure based on an Al3Pd structure in an Al70Co25Pd5 alloy has been studied by atomic-scale observations with high-resolution transmission electron microscopy (HREM) and high-angle annular detector dark-field (HAADF) technique using a scanning transmission electron microscope. From the electron microscopy observations, we can reveal an arrangement of atom columnar clusters, which produces peculiar shifts of diffraction spots in an electron diffraction pattern. Arrangements of transition-metal atoms in defect regions in the modulated structure are proposed from the observed HAADF image.     

Fine structure of mitochondrial helical filaments revealed by computer image analyses

In order to clarify the fine structure of the helical filaments appearing in the outer compartment of the mitochondria, Sprague-Dawley strain male rats were given 30% ethanol in drinking water for 90 days. The hepatic tissues of these animals were fixed with perfusion of glutaraldehyde via the portal vein followed by immersion in OsO4 and were then routinely processed for preparation of thin sections. Transmission electron micrographs of the sections were used for computer image analyses of the intramitochondrial helical filaments. With the application of the image analysis, it was revealed that the helical filaments show a right-hand rotating helix of 4.3 nm in thickness, 13.2 nm in diameter of the helix, and 15.7 nm in pitch. Also, with the multivariate statistical analysis and classification method of the IMAGIC image processing system, it was suggested in the classified images that the helical filament has substructures of rod-shaped particles of 4.3 nm in diameter. These particles are considered to be connected to each other and forming the helical structure of the filament.     

Fine structure of the dielectric-function spectrum in diamond

The spectra of the complete set of optical functions for three different diamond samples were calculated for the range of 0–32 eV. Calculations were based on the features of experimental reflection spectra; the Kramers-Kronig method was used. The features of the optical-function spectra and their distinctions for the three samples were analyzed. The method of the combined Argand diagrams was used to decompose for the first time the dielectric-function spectra into elementary components. The energies of these components and the oscillator strengths were determined. The structure of the components was compared to the structures of theoretical spectra of permittivity and the expected spectra of band-to-band transitions. Good agreement between the results of this study and the theory was obtained.     

Fine structure of microwave cross-polarization due to precipitation

Microwave crosspolarization due to precipitation is generally attributed to the nonspherical shape of particles. In the simplest model [1] one assumes that the precipitation medium has two symmetry planes and only the coherent part of the field is taken into account. A canting of these planes must be assumed to explain the crosspolarization between vertical and horizontal polarizations. Theoretical investigations based on the equation of radiative transfer suggest a certain importance of non coherent scattering effects. This paper reports results of a threeyear experimental work and aims to give a better insight on the crosspolarization mechanisms.     

The electronic structure of Ni-phthalocyanine/metal interfaces studied by X-ray and ultraviolet photoelectron spectroscopy

Nickel phthalocyanine (NiPc) thin films were grown stepwise on polycrystalline gold and silver substrates and the formed interfaces were characterized by X-ray and ultraviolet photoelectron spectroscopies (XPS, UPS). The variation of the XPS core level binding energy with NiPc film thickness yields information about band bending and interface dipoles. The valence band structure of the NiPc thin films was determined by UPS and exhibits four main features at binding energies 1.50 eV, 3.80 eV, 6.60 eV and 8.85 eV, respectively. The NiPc highest occupied molecular orbital (HOMO) cut-off was measured at ∼1.00 eV from the analyzer Fermi level and from the measured work function change of the growing NiPc film a final work function value for NiPc was estimated at 3.90 ± 0.10 eV. The main C1s peak of the NiPc film (∼5.0 nm) consists of two components at 284.8 eV (C–C bonds), 286.2 eV (C–N bonds) reflecting photoemission from multiple carbon sites within the molecule and a satellite at 287.9 eV, whereas the Ni2p and N1s peaks appear at ∼855.9 eV and ∼399.3 eV, respectively and are due to Ni–N bonds. The energy level diagrams of the NiPc/Au and NiPc/Ag interfaces were determined from a combination of the XPS and UPS results, yielding a hole injection barrier of 0.90 ± 0.10 eV for both substrates.     

虾夷扇贝(Patinopecten yesonensis)外套膜内平滑肌细胞的微细结构

早在 5 0年代后期 ,国外已有学者对牡蛎等双壳类内收肌内的平滑肌细胞进行了研究 ,并发现这些平滑肌细胞内有一种非常粗的肌丝 (即粗肌丝 )。其横径粗细不一 ,因而可将平滑肌细胞分为几种类型。此后还发现这种粗丝以副肌球蛋白为轴心 ,外围以肌动蛋白[1— 4 ] 。著者在检查虾夷扇贝外套膜 (以下简称套膜 )结构时注意到其中有细而长的平滑肌细胞。其形态特征及微细结构与脊椎动物的有所不同 [5] ,而与上述有关文献报道的双壳类内收肌的平滑肌细胞相同。今就观察所及特整理如下。材料与方法取成体虾夷扇贝套膜组织 ,按常规电镜术固定 ,包埋 ,…     

水稻胚乳细胞淀粉质体被膜与其增殖的关系

水稻胚乳细胞经高锰酸钾固定法固定后，显示出十分清晰的内膜结构，尤其展现了淀粉质体被膜与淀粉质体增殖在结构上的密切关系。常见的淀粉质体出芽、缢缩和形成中间隔板的增殖方式分别与淀粉质体外层被膜、内外层被膜、内层被膜的活动有关。另外，淀粉质体外层被膜也能出芽，形成双层膜小泡，再积累淀粉形成淀粉质体；而淀粉质体内层被膜向内出泡或内外层被膜同时内陷，在淀粉体内形成新淀粉质体，这是淀粉质体增殖的两种新方式。对淀粉质体被膜在淀粉质体增殖中的作用进行了讨论。     

Laser annealing of low dose Se-implanted GaAs studied by d.l.t.s.

Deep level transient spectroscopy (d.l.t.s.) has been applied to the study of deep levels in GaAs following post-implantation annealing using a Q-switched ruby laser. High concentrations (> 1015 cm?3) of deep trapping levels are observed in the laser melt region using a forward-bias voltage pulse.     

The inhomogeneous structure of the daytime Venusian ionosphere studied by Venera 15 and Venera 16 via radio sounding

The inhomogeneous structure of the Venusian daytime ionosphere is investigated on the basis of the data provided by the Venera 15 and Venera 16 space probes. The experimental data obtained from two-frequency radio sounding are restored, processed, and saved on modern media. Frequency and signal-power variations are analyzed, and, as a result, ionized layers on the solar illuminated planet’s daytime side are discovered at altitudes of 80–110 km. Results of spectral processing of frequency fluctuations observed during sounding of the upper region of the Venusian daytime ionosphere are presented. In this region, the electron concentration monotonically decreases with altitude up to the ionopause. Electron-concentration irregularities with dimensions of 5–60 km are revealed. The intensity and spectral index of the spatial spectrum of the ionospheric turbulence are estimated. Reliable information on the turbulence of the planet’s ionized shell is obtained for the first time.