We report the direct visualization of point defect clustering in {113} planes of silicon crystal using a transmission electron microscope, which was supported by structural modeling and high-resolution electron microscope image simulations. In the initial stage an accumulation of nonbonded interstitial–vacancy (I–V) pairs stacked at a distance of 7.68 Å along neighboring atomic chains located on the {113} plane takes place. Further broadening of the {113} defect across its plane is due to the formation of planar fourfold coordinated defects (FFCDs) perpendicular to chains accumulating I–V pairs. Closely packed FFCDs create a sequence of eightfold rings in the {113} plane, providing sites for additional interstitials. As a result, the perfect interstitial chains are built on the {113} plane to create an equilibrium structure. Self-ordering of point defects driven by their nonisotropic strain fields is assumed to be the main force for point defect clustering in the {113} plane under the existence of an energy barrier for their recombination.

Fatty acids (FAs) composition of eight zooxanthellate soft corals, Sinularia leptoclados, S. flexibilis, S. aff. deformis, S. lochmodes, S. cf. muralis, S. densa, S. notanda and S. cruciata collected in Van Phong Bay (Vietnam) were studied to identify possible origin of unsaturated FAs. The main FAs were 14:0, 16:0, 7-Me-16:1n-10, 16:1n-7, 16:2n-7, 18:0, 18:1n-9, 18:4n-3, 20:4n-6, 20:5n-3, 22:6n-3, 24:5n-6 and 24:6n-3. On the average, saturated, monounsaturated, and polyunsaturated FAs (PUFAs) contributed 35.6, 6.2 and 54.0% of total coral FAs, respectively. PUFAs of n-6 series predominated in all animals (n-6/n-3 > 1.6). The content of 20:4n-6 varied from 10.2 to 23.8%. The main n-3 PUFA was 18:4n-3 (on the average, 5.4%); the contribution of 20:5n-3 and 22:6n-3, typical PUFAs of marine organisms, was not more than 2.4 and 3.9%, respectively. In Sinularia, PUFAs were produced by endosymbiotic dinoflagellates (zooxanthellae) and the coral host tissue, or obtained with food. Zooxanthellae can be considered as the source of C16 PUFAs and 18:4n-3. The coral host synthesized 18:2n-7, 24:5n-6 and 24:6n-3 acids. The low content of 18:1n-7, saturated odd-chain FAs and saturated methyl-branched FAs indicated a negligible contribution of bacteria to total lipids of Sinularia. A comparison of the levels of diatom and dinoflagellate FA markers in coral and plankton lipids showed eukaryotic microalgae to play a secondary role in feeding of Sinularia. The high level of 20:4n-6 may be considered as an indicator of heterotrophic feeding of Sinularia.

The subspace-based technique is used for the estimation of the time of arrival and Doppler shift of a signal of known waveform. The tool to find required subspaces is a special orthogonal decomposition of received data. It allows one to concentrate Fisher information on the desired parameter in just a few of the first terms of the decomposition. This approach offers a low-dimensional vector of sufficient statistics. It leads to computationally efficient Bayesian estimation. Besides, it results in expansion of the signal-to-noise ratio (SNR) range for effective maximum likelihood (ML) estimation. Finally, we can obtain independent time arrival and Doppler shift estimations based on generalized eigenvectors.

The present paper presents experimental results of the transverse and longitudinal phase volume for the expanding multicharged ions in laser produced plasma, created by focusing a CO2-laser (beam) onto a Pb207 target. The total number of Pb207 ions (with Z = 1 or 2 and Z = 6), the ion current duration and amplitude at a distance of 1 m from the laser target within 10−2 steradians are determined. The measured experimental parameters of the laser heavy ion source are compared with the driver requirement for the heavy ion inertial fusion (HIIF) programme.

The phenomena observed in the experiment confirm the results of numerical calculations using a two temperature hydrodynamic programme.

Clear understanding of the structural and morphological transformations on the crystal surfaces can only be extracted from considerations of the dynamical properties of surface evolution. So ultra high vacuum reflection electron microscopy (UHV REM) has been applied to in situ studies of step behaviors on the silicon surfaces during various treatments. Dependence of the surface morphology on the number of parameters is reviewed with new results. Special attention is paid to influence of the electromigration phenomena and strain fields on structural evolution of the surfaces during sublimation, phase transition and epitaxial growth. The stability of the atomic step distributions is discussed in the frame of kinetical morphological transitions on silicon surfaces during DC heating of studied crystal [1].

The step motion during sublimation shows a strong influence of stress fields on the step configurations [2]. The importance of surface stress is obvious because in equilibrium conditions there is a residual stress on the surface due to existence of broken bonds.

An estimate is made of the maximum range over which the motion of a particle about the Sun and in the galactic field is stable in Hill's sense. An equation fitting the Hill surface is found, with allowance made for the fact that the galactic potential differs from that of a point mass. The volume enclosed by the surface is 3.35 cubic parsecs, the greatest distance from the Sun being 1.42 parsecs, this being along the line to the centre of the Galaxy.