8,232 research outputs found
The motion of ascending and descending spheres
Measurements of self-induced motions of spheres ascending and descending in deep water tan
Geology of the Peebles Quadrangle, Adams County, Ohio
Author Institution: Department of Geology, Eastern Kentucky UniversityThe rock sequence exposed in the Peebles quadrangle, Adams Co., Ohio, consists of over 240 m of Ordovician through Mississippian age rocks. These carbonate rocks, shales, and sandstones have been subdivided into 13 formations. Units which have been recently recognized in this area include the Bull Fork Formation (Upper Ordovician), the Preachersville Member of the Drakes Formation (Upper Ordovician), the Drowning Creek Formation (Silurian), and the Three Lick Tongue of the Chagrin Member of the Ohio Shale (Upper Devonian). These strata generally dip 6—8 m per km to the east, but the dip increases to 10—11 m per km in the southeast portion of the quadrangle. The increase in dip is due to the Adams Co. monocline. The monocline is thought to be the result of draping of Paleozoic rocks over a possible basement fault
Numerical simulations of expanding supershells in dwarf irregular galaxies. I. Application to Holmberg I
Numerical hydrodynamical modelling of supernova-driven shell formation is
performed with a purpose to reproduce a giant HI ring (diameter 1.7 kpc) in the
dwarf irregular galaxy Holmberg I (Ho I). We find that the contrast in HI
surface density between the central HI depression and the ring is sensitive to
the shape of the gravitational potential. This circumstance can be used to
constrain the total mass (including the dark matter halo) of nearly face-on
dwarf irregulars. We consider two models of Ho I, which differ by an assumed
mass of the dark matter halo M_h. The contrast in HI surface density between
the central HI depression and the ring, as well as the lack of gas expansion in
the central hole, are better reproduced by the model with a massive halo of
M_h=6.0*10^9 M_sun than by that with a small halo of M_h=4.0*10^8 M_sun,
implying that Ho I is halo-dominated. Assuming the halo mass of 6.0*10^9 M_sum,
we determine the mechanical energy required to form the observed ring equal to
(3.0 +- 0.5)*10^53 ergs, equivalent 300+-50 Type II supernovae. The inclination
of Ho I is constrained to 15-20 degrees by comparing the modelled HI spectrum
and channel maps with those observed.Comment: 11 pages, 11 figures, accepted for publication in Astronomy and
Astrophysic
SNAP-8 corrosion program Quarterly progress report, period ending 31 May 1965
Differences in corrosion and mass transfer rates in corrosion loops for SNAP-8 system and effectiveness of cold trapping in reducing hydrogen concentratio
Tensile-strength apparatus applies high strain-rate loading with minimum shock
Tensile-strength testing apparatus employs a capillary bundle through which a noncompressible fluid is extruded and a quick-release valve system. This apparatus applies the test loads at relatively constant very high strain rates with minimal shock and vibration to the tensile specimen and apparatus
Snap-8 corrosion program quarterly progress report, period ending 28 feb. 1965
SNAP-8 corrosion program - hydrogen solubility in sodium-potassium, permeability of hydrogen and deuterum through stainless steel, and phase equilibri
EXAFS Analysis of Size-Constrained Semiconducting Materials
Semiconducting materials such as CdSe, CdS, PbS and GaP are included in crystalline zeolite Y and mordenite and structurally flexible ethylene-methacrylic acid copolymer solid matrices. EXAFS analysis reveals formation of species with dimensions of molecular size up to ca. 13 A in the crystalline hosts, while the polymer matrices allow agglomeration of larger semiconducting particles. Zeolite anchored structures are distinctively different to small particles with bulk crystal structure as usually found in colloidal systems
Synthesis and characterization of group III-V semiconductor clusters: gallium phosphide GaP in zeolite Y
Toxic Hazards Research Unit annual technical report, 1969 Final report, Jun. 1968 - May 1969
Apollo materials toxicity screening tests and effects of ethylene glycol, monomethylhydrazine, NF3, OF2, and ClF
- …
