Photoelectric Radial Velocities, Paper XVIII Spectroscopic Orbits for Another 52 Binaries in the Hyades Field     

R. F. Griffin 《Journal of Astrophysics and Astronomy》2012,33(1):29-200

Spectroscopic orbits are presented for 52 stars in the Hyades field, of which 41 prove to be actual members of the Hyades (with some reservations in two cases). Most of the stars concerned have not had orbits published for them previously. Three of them are of higher multiplicity. The already-known double-lined eclipsing system van Bueren 22 is demonstrated to be a triple system, as was obliquely announced 25 years ago; its ??outer?? orbit, which has a period of about 8 years, is now determined. Van Bueren 75 is already known to be triple, but here the visual secondary is shown to be the (single-lined) spectroscopic sub-system, and an independent spectroscopic solution is given for the 40-year orbit of what has hitherto been regarded as the ??visual?? pair. Van Bueren 102, for which a close visual companion was discovered comparatively recently, is a single-lined binary whose ?? -velocity has shown a steady drift over at least the last 30 (probably 50) years. Three stars, vB 39, 50 and 59, have notably high eccentricities of 0.85, 0.98 and 0.94, respectively; they have quite long periods (especially vB 50, which is over 100 years), and every one of them contrived to pass the whole of its recent periastron passage (about 180° of true anomaly) between seasons, at the time of year when the Hyades are unobservable!  相似文献   

Photoelectric Radial Velocities, Paper XX 45 Years’ Monitoring of the Radial Velocities of the Redman?K?Stars     

R. F. Griffin  A. Stroe 《Journal of Astrophysics and Astronomy》2012,33(2):245-278

The ??Redman K stars?? are a group of 80-odd seventh-magnitude late-type stars, nearly all giants, distributed along the Galactic equator between approximate longitudes 50° and 150° (roughly Sagitta to Cassiopeia). Their radial velocities have been measured systematically once per season in 30 of the 45 seasons from 1966 to 2010/11. At least 26 of them (30%) have proved to vary in velocity. Orbits have been derived for all but one of the 26, many of them having longer periods than have normally been associated with spectroscopic binaries; several are comparable with, or longer than, the present duration of the observing campaign. Also reported here are radial-velocity measurements made casually of stars seen in the fields of some of the Redman stars. Two of the companions have proved to vary in velocity on long time-scales, and (somewhat preliminary) orbits are given for them.  相似文献   

Photoelectric Radial Velocities, Paper XIX Additional Spectroscopic Binaries among the Redman K?Stars     

R. F. Griffin 《Journal of Astrophysics and Astronomy》2012,33(2):227-244

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An Australian provenance for the eastern Otago Schist protolith,South Island,New Zealand: evidence from detrital zircon age patterns and implications for the origin of its gold     

C. J. Adams  W. L. Griffin 《Australian Journal of Earth Sciences》2017,64(6):703-721

Uranium–lead age patterns of detrital zircons in Otago Schist meta-sandstones from eastern Otago, including areas of orogenic gold mineralisation, are mostly consistent with a Rakaia Terrane (Torlesse Composite Terrane) accretionary wedge protolith. Southwest of the Hyde-Macraes and Rise & Shine shear zones the depositional age is regarded as Middle–Late Triassic. At the south and west margins, there are two areas in the Late Triassic Waipapa Terrane protolith. Northeast of the Hyde-Macraes Shear Zone, the schist protolith has Middle to Late Triassic and middle to late Permian depositional ages of Rakaia Terrane affinity. At the northeastern margin of the Hyde-Macraes Shear Zone, there is a narrow strip with a mid-Carboniferous protolith, which may be a counterpart of the Carboniferous accretionary wedge in the New England Orogen, eastern Australia. Ordovician–Silurian zircons are a minor but distinctive feature in many of the protolith age patterns and form significant age components at hard-rock gold locations. These constrain the provenance of Rakaia Terrane protolith sediments to Late Triassic time and within the Permian–Triassic magmatic arcs at the northeastern Australian continental margin and partly within the Ordovician–Silurian granitoids of the Charters Towers Province hinterland and environs. The latter have extensive gold mineralisation and thus upon exhumation might be the origin of Otago gold.  相似文献   

A survey of the occurrence of Bacillus anthracis in North American soils over two long-range transects and within post-Katrina New Orleans   总被引：2，自引：2，他引：0  

Dale W. Griffin  Terry Petrosky  Suzette A. Morman  Vicki A. Luna 《Applied Geochemistry》2009,24(8):1464-1471

Soil samples were collected along a north–south transect extending from Manitoba, Canada, to the US–Mexico border near El Paso, Texas in 2004 (104 samples), a group of sites within New Orleans, Louisiana following Hurricane Katrina in 2005 (19 samples), and a Gulf Coast transect extending from Sulphur, Louisiana, to DeFuniak Springs, Florida, in 2007 (38 samples). Samples were collected from the top 40 cm of soil and were screened for the presence of total Bacillus species and Bacillus anthracis (anthrax), specifically using multiplex-polymerase chain reaction (PCR). Using an assay with a sensitivity of 170 equivalent colony-forming units (CFU) g⁻¹ field moist soil, the prevalence rate of Bacillus sp./B. anthracis in the north–south transect and the 2005 New Orleans post-Katrina sample set were 20/5% and 26/26%, respectively. Prevalence in the 2007 Gulf Coast sample set using an assay with a sensitivity of 4 CFU g⁻¹ of soil was 63/0%. Individual transect-set data indicate a positive relation between occurrences of species and soil moisture or soil constituents (i.e., Zn and Cu content). The 2005 New Orleans post-Katrina data indicated that B. anthracis is readily detectable in Gulf Coast soils following flood events. The data also indicated that occurrence, as it relates to soil chemistry, may be confounded by flood-induced dissemination of germinated cells and the mixing of soil constituents for short temporal periods following an event.  相似文献   

METEORITE MATERIAL IN THE MINERALOGISK-GEOLOGISK MUSEUM,OSLO     

W. L. Griffin 《Meteoritics & planetary science》1974,9(2):157-171

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Development of techniques for monitoring gas-phase sodium species formed during coal combustion and gasification     

B. L. Chadwick  R. A. Ashman  A. Campisi  G. J. Crofts  P. D. Godfrey  P. G. Griffin  A. L. Ottrey  R. J. S. Morrison 《International Journal of Coal Geology》1996,32(1-4)

The development of techniques suitable for on-line analysis of gas-phase molecular sodium species, resulting from the combustion and gasification of low-rank coals is described. In particular two techniques have been demonstrated, these are: (a) laser-induced photofragment fluorescence and (b) microwave spectroscopy. The photofragment technique can be applied in situ and yields excellent detection limits (<0.1 ppb of NaCl and 1 ppb NaOH) with good discrimination between the two major gas-phase species — NaCl and NaOH. Limitations of this technique include absorption of the ultraviolet (UV) photolysis excitation by other chemical species and particulates. Microwave spectroscopy shows promise in determining the sodium species distribution in the gas-phase. A purpose built analytical instrument (known as MILLIJET HT) is being developed for application in high-temperature environments. Early results indicate detection limits of <100 ppb NaCl. Lack of sensitivity for NaOH is being attributed to the formation of NaOH dimers and larger clusters. Detailed calculations of the dimer structure and the dimer-monomer reaction have been undertaken in order to maximise the performance of the instrument.  相似文献   

An experimental calibration of the “nickel in garnet” geothermometer with applications,by D. Canil: discussion     

W. L. Griffin  C. G. Ryan 《Contributions to Mineralogy and Petrology》1996,124(2):216-218

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大别造山带北缘后碰撞富钾火山岩：地球化学与岩石成因   总被引：12，自引：10，他引：12  

邱检生  王德滋等 《岩石学报》2002,18(3):319-330

大别造山带北缘晚中生代富钾火山岩分布在磨子潭-晓天断裂以北的上叠式火山盆地中，主要为一套以钾玄岩-粗安岩-安粗岩-粗面岩为主体的中偏碱性岩石组合，晚期出现少量碱性火山岩。化学成分上具有富碱、富钾、贫钛、氧化系数较高等特点。岩石的Rb、Ba、Th、Pb等大离子亲石元素含量高，富轻稀土，La/Nb、Ba/Nb及LREE/HREE比值高，并且有显著的Nb、Ti负异常和Pb正异常，而铕异常则不明显。富钾火山岩的Isr值较高（=0.70872-0.70895）,εNd(t)值显著偏低（=-14.62--18.51）。根据对岩石产出动力地质背景及地球化学特征的综合分析，结合同位素组成的混合模拟，表明本区富钾火山岩最可能起源于受俯冲陆壳析出流体交代作用所形成的富集地幔（EM I）的部分熔融。  相似文献   

Trace-element zonation in garnets from The Thumb: heating and melt infiltration below the Colorado Plateau     

Douglas Smith  William L. Griffin  Chris G. Ryan  Soey H. Sie 《Contributions to Mineralogy and Petrology》1991,107(1):60-79

Proton microprobe (PIXE) analysis of garnet, pyroxene, and olivine for Zr, Y, Ga, Ge, Sr, Ni, Mn and Zn has been combined with electron-probe and petrographic analysis to interpret the histories of garnetperidotite xenoliths from the minette neck at The Thumb on the Colorado Plateau. Garnet in seven rocks contains 10–110 ppm Zr and 25–95 ppm Ni. Substantial parts of these ranges are preserved in single, zoned garnets (Zr, 25–90 ppm; Ni, 25–60 ppm). Pyroxene and olivine are more homogeneous and equilibrated more quickly than granet to changing temperatures and metasomatic fluxes. The distribution coefficient of Ti between pyroxene and garnet rims may be sufficiently sensitive to pressure to be used as a geobarometer. Zirconium and Ti appear to have behaved similarly during melt infiltration and diffusion within garnet. Nickel in garnet is a sensitive recorder of temperature. A temperature of 900° C or less calculated from Ni in the cores of large garnets in one rock is at least as cool as that calculated for the Archaean Kaapvaal craton at similar depth, and the low temperature may be due to cooling of the Plateau lithosphere by the subducted Farallon plate. The zonation of these garnets to Ni-enriched rims has been simulated numerically by heating 260° C at 0.02°/year, followed by overgrowth of a rim and short annealing. Garnet in another rock records a temperature decrease of about 70° C, but Ni is more homogeneous in garnets in the other five rocks. The diverse temperature histories are attributed to local melt-mantle interactions. Calculated pressures and temperatures of xenoliths from The Thumb form a grouping similar to those for high-temperature parts of inflected geotherms in other xenolith suites, and the similarity is evidence for both the reality and the transients nature of the calculated inflections. Garnet that is zoned in Zr, Y, Ti and other elements preserves evidences for grain growth in response to melt infiltration in four of seven rocks. The ranges of both major and trace elements in the xenolith suite may be due largely to enrichment processes following earlier depletion.  相似文献