<Emphasis Type="Italic">Hydrogeology Journal</Emphasis> in 2004     

Clifford?VossEmail author  Perry?Olcott  Robert?Schneider  Christine?Watson 《Hydrogeology Journal》2004,12(6):611-612

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Infrared and Raman spectra of lunar samples from Apollo 11, 12 and 14     

Clive H. Perry  D. K. Agrawal  E. Anastassakis  R. P. Lowndes  A. Rastogi  N. E. Tornberg 《Earth, Moon, and Planets》1972,4(3-4):315-336

We report the room temperature infrared reflectance spectra of several lunar surface rocks in the form of polished slices or butt ends. The spectra were obtained over the frequency range 20-2000 cm^–1 throughout the mid and far infrared (5-500µ) region of the electromagnetic spectrum where the fundamental internal and lattice vibrational modes of all minerals and rocks occur.Some fines samples were examined as pressed pellets and their reflectivities compared with the bulk samples. Several terrestrial minerals and rocks were also investigated. Kramers-Kronig analyses of these reflectance spectra were undertaken and the dispersion of the dielectric response ( and ) and the optical constants (n andk) have been determined over this frequency range. The low frequency and high frequency (infrared) dielectric constants were also calculated from the reflectance data.Raman light scattering measurements were made on all the samples supplied from the first three Apollo missions. Large background scattering proved to be the greatest experimental problem. Successful spectra in nearly all cases were obtained from small crystalline inclusions imbedded in the main ground mass. Some crystalline bulk rocks containing many very fine inclusions gave identifiable spectra and at least three different types were obtained.Supported by NASA Grant NGR 22-011-069 and by a Northeastern University Grant for Basic Research.  相似文献   

Bacterial iron oxide reduction in a terrigenous sediment-impacted tropical shallow marine carbonate system, north Jamaica   总被引：1，自引：0，他引：1  

Kevin G. Taylor  Christopher T. Perry  Anthony M. Greenaway  Philip G. Machent 《Marine Chemistry》2007,107(4):449-463

Discovery Bay, a carbonate-dominated embayment in north Jamaica, has been subject to inputs for 40 years of iron-rich bauxite sediment associated with the local mining and transport of processed bauxite. As such, this site is an ideal natural laboratory to study the records and impacts of iron oxide inputs upon geochemical, diagenetic, and microbial processes in tropical carbonate sediments.Total Fe contents in sites in the bay not receiving bauxite inputs are negligible and porewater Ca²⁺, SO₄²⁻ and Cl⁻ indicate that bacterial sulphate reduction is an important process. In contrast, surface sediments receiving bauxite inputs contain significant total Fe, from 44 μmol/g in shallow (5 m water depth) sites to 110 μmol/g in deeper (20 m water depth) sites. Up-core increases in total Fe record increased temporal inputs into the bay. Within these Fe-rich sediments porewater data shows the presence of Fe^II released by bacterial Fe^III reduction. There is no direct evidence for significant bacterial sulphate reduction in these sediments. Iron oxides within all bauxite-impacted sediments display a high potential reducibility, from 40% to 80% of the total Fe present as dithionite-extractable Fe^III. Experimental analysis of the potential susceptibility to, and rates of, bacterial Fe^III reduction, utilising Discovery Bay sediment and Shewanella putrefaciens CN32 (a known Fe^III-reducer) has confirmed the high bacterial reducibility of iron oxides within the sediment. Up to 75% of initial dithionite-extractable Fe^III in the sediments was reduced over 15 days.The presence of iron oxides within the Discovery Bay shallow marine carbonate systems has markedly altered the chemical diagenetic processes taking place, with a shift from apparent dominance of bacterial sulphate reduction at non-impacted (Fe-poor) sites, to highly significant bacterial Fe^III reduction in Fe-rich bauxite-impacted sediments. Given the perceived global increases in terrigenoclastic sediment inputs into tropical carbonate systems as a result of land-use and climate changes, coupled with the documented role that iron oxide reduction plays in nutrient and contaminant cycling in sediment systems, more research into the perturbation of early diagenesis by iron oxide inputs is required.  相似文献   

Virtual observatories for space and solar physics research     

Christopher C. Harvey  Michel Gangloff  Todd King  Christopher H. Perry  D. Aaron Roberts  James R. Thieman 《Earth Science Informatics》2008,1(1):5-13

As soon as the first data became available online over the Internet, it was obvious that different sites holding related datasets should appear to the end user as a single data system, even if the data itself is stored at multiple locations. To achieve this objective in the context of continuing parallel development of multiple data centres, in 2003 several actors in the realm of space plasmas created the international consortium Space Physics Archive Search and Extract (SPASE). Since 2005 US participation in SPASE has been supported by NASA, and early in 2006 NASA funded five new Virtual Observatories to cater for different aspects of solar system plasma science. This paper outlines the current status of the SPASE effort, the opportunities it offers, its specificities with respect to other parts of the astronomical virtual observatory, and the possibilities it offers for space weather.

Christopher C. HarveyEmail:

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Moveable feast: The incredible journeys of the things we eat     

Peter Perry 《New Zealand geographer》2008,64(1):88-89

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To what extent do improved irrigation technologies extend aquifer life?     

C. J. Perry  P. J. G. J. Hellegers 《Hydrogeology Journal》2012,20(5):907-913

World financial support for Yemen has concentrated on improved irrigation technology as the primary means to reduce the rate of overexploitation of Yemen’s aquifers. An analysis of the impact of such investments on cumulative water abstraction, water savings and the life of an aquifer is presented. It shows that these investments have limited potential to extend aquifer life. The returns are highest in areas with significant remaining resources, and are not attractive in the most severely stressed areas. The analysis also shows that improved irrigation technologies increase the profitability of pumping for the farmer, exacerbating problems of over-abstraction. Finally, it shows that water savings depend on the hydrogeological situation. The policy implications of these findings are discussed in relation to Yemen, an exceptionally water-short country where most of the aquifers in groundwater-irrigated areas are severely over-drafted.  相似文献   

Radius and limb topography of Mercury obtained from images acquired during the MESSENGER flybys     

Jürgen Oberst  Stephan Elgner  F. Scott Turner  Mark E. Perry  Robert W. Gaskell  Maria T. Zuber  Mark S. Robinson  Sean C. Solomon 《Planetary and Space Science》2011,59(15):1918-1924

Analysis of images obtained by the MESSENGER spacecraft during its three flybys of Mercury yields a new estimate for the planet's mean radius of 2439.25±0.69 km, in agreement with results from Mariner 10 and Earth-based observations, as well as with MESSENGER altimeter and occultation data. The mean equatorial radius and polar radius are identical to within error, suggesting that rotational oblateness is negligible when compared with other sources of topography. This result is consistent with the small gravitational oblateness of the planet. Minor differences in radius obtained at different locations reflect regional variations in topography. Residual topography along three limb profiles has a dynamic range of 7.4 km and a root-mean-square roughness of 0.8 km over hemispherical scales. Following MESSENGER's entry into orbit about Mercury in March 2011, we expect considerable additional improvements to our knowledge of Mercury's size and shape.  相似文献   

Chemical element concentrations in black locust (<Emphasis Type="Italic">Robinia pseudoacacia</Emphasis> L.) and green ash (<Emphasis Type="Italic">Fraxinus pennsylvanica</Emphasis> Marsh.) leaves at the reclaimed Green Valley coal Mine,Indiana, USA     

Ryan R. Jensen  Sandra S. Brake  Stephen F. Wolf  Matthew F. Bekker  Perry James Hardin  Mark W. Jackson 《Environmental Earth Sciences》2010,60(7):1391-1405

The Green Valley Mine in Indiana was abandoned in 1963 after 15 years of coal mining. Reclamation began in 1994 and ended in 1999 with the dense planting of twelve different tree species. By 2006, only green ash (Fraxinus pennsylvanica Marsh.) and black locust (Robinia pseudoacacia L.) had survived in any significant numbers. Given the acid mine drainage found at the site, we sought to determine whether element toxicity originating from mine waste was responsible for the extirpation of the trees. Leaf samples taken from 125 mine trees and 29 control trees were acquired and assayed for 41 element concentrations using inductively coupled plasma mass spectrometry (ICPMS). Except for sodium, there was no compelling evidence to indicate that toxic elemental levels were responsible for the widespread tree deaths. In addition to sodium toxicity, we suspect that micronutrient deficiency was a primary factor explaining the extirpation of trees at the mine.  相似文献   

Upper-mantle thermochemical structure below North America from seismic–geodynamic flow models     

H. K. C. Perry  A. M. Forte  D. W. S. Eaton 《Geophysical Journal International》2003,154(2):279-299

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Belgium by raymond folkextone: Drawson (studies in industrial Geography)     

P.J. Perry 《New Zealand geographer》1977,33(1):45-45

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