The Tucson revised index of asteroid data     

D. Bender  E. Bowell  C. Chapman  M. Gaffey  T. Gehrels  B. Zellner  D. Morrison  E. Tedesco 《Icarus》1978,33(3):630-631

Attention is called to the availability of the TRIAD computer file, a compilation of all reliable physical parameters for minor planets.  相似文献   

Asteroid sizes and albedos     

David Morrison 《Icarus》1977,31(2):185-220

The radiometric method of determining diameters of asteroids is reviewed, and a synthesis of radiometric and polarimetric measurements of the diameters and geometric albedos of a total of 187 asteroids is presented. All asteroids with diameters greater than 250 km are identified, and statistical studies can be carried out of the size distributions of different albedo classes down to 80-km diameter for the entire main asteroid belt (2.0–3.5 AU). The distribution of albedos is strongly bimodal, with mean albedos for the C and S groups of 0.035 and 0.15, respectively. The C asteroids outnumber the S at all sizes and all values of semi-major axis, increasing from a little over half the population inside 2.5 AU to more than 95% beyond 3.0 AU; for all objects with D > 70 km, the ratio C/(C+S) is 0.88 ± 0.04. More than half of all asteroids in this size range have a > 3.0 AU. The M asteroids constitute about 5% of the population for a < 3.0 AU, but no members of of this class have been identified in the outer belt. There are no significant differences between the distributions of C, S, and M asteroids for the largest asteroids (D > 200 km) and for those of intermediate size (200–270 km). The total mass in the belt, down to 70-km size, but excluding Ceres, is about 2 × 10²⁴ g. Evidence is presented that several large asteroids rotate in a prograde sense, and that a real difference existsbetween the bulk densities of Ceres and Vesta.  相似文献   

The Changing Geography of Full-Time Employment in New Zealand     

Philip S. Morrison 《New Zealand geographer》1984,40(2):78-88

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Zinc concentrations in marine macroalgae and a lichen from western Ireland in relation to phylogenetic grouping, habitat and morphology     

Stengel DB  Macken A  Morrison L  Morley N 《Marine pollution bulletin》2004,48(9-10):902-909

Zinc concentrations in 19 species of marine macroalgae and a lichen from western Ireland (Spiddal, Co. Galway) were analysed by atomic absorption spectrophotometry. Algae were collected from a single site but occupied different shore levels and belonged to distinct phylogenetic groupings and to different (previously recognised) morphological groups. Concentrations ranged from 15-115 microg g(-1) dry weight. The greatest variation in concentration occurred amongst the red algal species, containing both maximum and minimum concentrations. Zn concentrations in brown and green algae were generally lower than those in red algae. When grouped according to thallus morphology, thin, branched sheets (which consisted mainly of red algae) contained the highest Zn concentrations. In filamentous algae, Zn levels were higher than in thick-leathery or coarsely branched algae. However, all green algal species examined had similar Zn concentrations, despite their different morphologies. In brown algae, the highest Zn levels were detected in mid-shore fucoids (Fucus vesiculosus and Fucus serratus), while thicker, subtidal and low-shore brown algae (Laminaria digitata, Halydris siliquosa) exhibited lower Zn concentrations. The lowest Zn concentrations were detected in high-intertidal species (Fucus spiralis, Pelvetia canaliculata), the only marine lichen examined (Ramalina siliquosa) and a red crustose alga (Corallina officinalis). In all morphological groups, red algal representatives contained relatively higher levels of Zn, the exception being Corallina officinalis. Zn levels in 4 species from a second, estuarine site in Galway Bay exhibited the same relative differences amongst species, but were all consistently higher than in algae from Spiddal. It is concluded that Zn accumulation in macroalgae is closely related to ecological growth strategies, following a functional-form model. However, the phylogenetic origin of species which determines carbohydrate and phenol composition, and responses to ambient environmental conditions ultimately determine, the availability of binding sites for polyvalent cations.  相似文献   

Moons and planets: (2nd Ed.). William K. Hartmann. Wadsworth,Belmont, Calif., 1983. $29.95     

David Morrison 《Icarus》1983,56(1):192-193

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Modification of an equation of Szebehely     

Foster Morrison 《Celestial Mechanics and Dynamical Astronomy》1977,16(1):39-40

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Variation in the hatching length of spring-spawned herring larvae (Clupea harengus L.) on Ballantrae Bank in the Firth of Clyde     

Rankine  Paul W.; Cargill  Lindsay H.; Morrison  John A. 《ICES Journal of Marine Science》1990,46(3):333-339

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Cloning and analysis of the CYP1A promoter from the atlantic killifish (Fundulus heteroclitus)     

Wade H. Powell  Hilary G. Morrison  E. Jennifer Weil  Sibel I. Karchner  Mitchell L. Sogin  John J. Stegeman  Mark E. Hahn 《Marine environmental research》2004,58(2-5):119

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Spectroscopic study of the long-period dust-producing WC7pd+O9 binary HD 192641     

L. Lefèvre  S. V. Marchenko  S. Lépine  A. F. J. Moffat  A. Acker  T. J. Harries  K. Annuk  D. A. Bohlender  H. Demers  Y. Grosdidier  G. M. Hill  N. D. Morrison  D. C. Knauth  G. Skalkowski  S. Viti 《Monthly notices of the Royal Astronomical Society》2005,360(1):141-152

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Hydrothermal alteration of late- to post-tectonic Lyon Mountain Granitic Gneiss, Adirondack Mountains, New York: Origin of quartz–sillimanite segregations, quartz–albite lithologies, and associated Kiruna-type low-Ti Fe-oxide deposits     

J. Mclelland  J. Morrison  B. Selleck  B. Cunningham  C. Olson  K. Schmidt 《Journal of Metamorphic Geology》2002,20(1):175-190

Quartz–sillimanite segregations, quartz–albite lithologies (Ab_95–98), and Kiruna‐type low‐Ti iron‐oxide deposits are associated with late‐ to post‐tectonic (c. 1055 Ma) leucogranites of Lyon Mountain Gneiss (LMG) in the Adirondack Mountains, New York State. Most recent interpretations of these controversial features, which are global in occurrence, favour hydrothermal origins in agreement with results presented here. Field relations document that quartz–sillimanite veins and nodules cut, and therefore post‐date, emplacement of host LMG leucogranites. Veins occur in oriented fracture networks, and aligned trains of nodules are interpreted as disrupted early veins. Late dykes of leucogranite cut veins and nodules demonstrating formation prior to terminal magmatism. Veins and nodules consist of sillimanite surrounded by quartz that commonly embays wall‐rock feldspar indicating leaching of Na and K from LMG feldspar by acidic hydrothermal fluids. Subsequent, and repeated, ductile flow disrupted earlier veins into nodular fragments but produced little grain shape fabric. Geochemical and petrographic studies of quartz–albite rock indicate that it formed through metasomatic replacement (albitization) of LMG microperthite by sodic hydrothermal fluids that resulted in diagnostic checkerboard albite. Low‐Ti iron‐oxide ores are commonly associated with the quartz–albite sub‐unit, and it is proposed that hydrothermal fluids related to albitization transported Fe as well. The regional extent of sodic alteration suggests large quantities of surface‐derived hydrothermal fluids. Fluid inclusion and oxygen isotope data are consistent with high temperature, regionally extensive fluids consisting primarily of evolved surface‐derived brines enriched in Na and Cl. Quartz–sillimanite veins and nodules, which are significantly more localised phenomena and require acidic fluids, were most likely formed from local magmatic fluids in the crystallizing carapaces of LMG plutons.  相似文献