Static load versus settlement for geometric shapes on cohesionless soil

Static loading versus settlement for circular plate, cone, and sphere on cohesionless soil - spacecraft landing gear stud

Behavior of a sandy clay under vertical impact of geometric shapes

Sandy clay response under vertical impact of cone, plate, and plane geometric shape

Tethers in space handbook

The handbook provides a list and description of ongoing tether programs. This includes the joint U.S.-Italy demonstration project, and individual U.S. and Italian studies and demonstration programs. An overview of the current activity level and areas of emphasis in this emerging field is provided. The fundamental physical principles behind the proposed tether applications are addressed. Four basic concepts of gravity gradient, rotation, momentum exchange, and electrodynamics are discussed. Information extracted from literature, which supplements and enhances the tether applications is also presented. A bibliography is appended

X-RAY STRUCTURAL STUDIES ON 3 ANALOGS OF THE ALPHA-ANOMER OF THE ANTITUMOR ANTIBIOTIC SHOWDOMYCIN - DIFFERENTIAL RING-PUCKERING EFFECTS OF HYDROXYL SUGAR SUBSTITUENTS IN LYXO AND ARABINO CONFIGURATIONS

The crystal structures of three a-analogues of the anititumour antibiotic showdomycin (1) have been determined at room temperature. They are 2-(a-D-2'- deoxyribofuranosyl)maleimide (2), 2-(a-D-arabinofuranosyl) maleimide (3) and 2-(a-D-lyxofuranosyl)- maleimide (4). The structures were refined to R factors of 0-039, 0-042 and 0-029 for 971, 1025 and 716 observed reflections. The conformational properties of the sugar rings are discussed in detail, in relation to the differing hydroxyl group substitutions. Compounds (2) and (3) have CY-endo, C4"-exo and CY-endo ring puckers, whereas (3) has C2"-endo, C l'-exo puckers. Compound (3) has an intramolecular hydrogen bond between the 05' and 02' hydroxyl groups. This and the sugar pucker difference are in accord with NMR chemical shift data for the O5' and O2' protons. Crystal data: compound (2), C9H11NOs, orthorhombic, P212~21, a = 5-916 (1), b = 8-191 (1), c = 19.691 (3) A, Z = 4; compound (3), C9HIINO6, orthorhombic, P212121, a = 6.785 (1), b = 8.006 (1), c = 17.564 (2) A, Z= 4; compound (4), C9HI1NO6, monoclinic, P2~, a = 8.681 (1), b = 5.135 (1), c= 11-364 (1) A, Z= 2

The role of rotation on Petersen Diagrams. II The influence of near-degeneracy

In the present work, the effect of near-degeneracy on rotational Petersen diagrams (RPD) is analysed. Seismic models are computed considering rotation effects on both equilibrium models and adiabatic oscillation frequencies (including second-order near-degeneracy effects). Contamination of coupled modes and coupling strength on the first radial modes are studied in detail. Analysis of relative intrinsic amplitudes of near-degenerate modes reveals that the identity of the fundamental radial mode and its coupled quadrupole pair are almost unaltered once near-degeneracy effects are considered. However, for the first overtone, a mixed radial/quadrupole identity is always predicted. The effect of near-degeneracy on the oscillation frequencies becomes critical for rotational velocities larger than 15-20 km/s, for which large wriggles in the evolution of the period ratios are obtained (up $10^{-2}$). Such wriggles imply uncertainties, in terms of metallicity determinations using RPD, reaching up to 0.50 dex, which can be critical for Pop. I HADS (High Amplitude \dss). In terms of mass determinations, uncertainties reaching up to 0.5 M_sun are predicted. The location of such wriggles is found to be independent of metallicity and rotational velocity, and governed mainly by the avoided-crossing phenomenon.Comment: 8 pages, 7 figures, 1 table. (accepted for publication in A&A