Desert varnish: an environmental recorder for Mars     

Randall S Perry  Mark A Sephton 《Astronomy& Geophysics》2006,47(4):4.34-4.35

Randall S Perry and Mark A Sephton discuss a target material for Mars Sample Return: rocks coated with desert varnish, a mineral layer that records past surface climates on Earth, and probably on Mars too.  相似文献   

Increasing a freshwater lens below a creek ridge using a controlled artificial recharge and drainage system: a case study in the Netherlands     

Pieter S. Pauw  Esther S. van Baaren  Martijn Visser  Perry G. B. de Louw  Gualbert H. P. Oude Essink 《Hydrogeology Journal》2015,23(7):1415-1430

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Long-Term Tracking of Corotating Density Structures Using Heliospheric Imaging     

I. Plotnikov  A. P. Rouillard  J. A. Davies  V. Bothmer  J. P. Eastwood  P. Gallagher  R. A. Harrison  E. Kilpua  C. Möstl  C. H. Perry  L. Rodriguez  B. Lavraud  V. Génot  R. F. Pinto  E. Sanchez-Diaz 《Solar physics》2016,291(6):1853-1875

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<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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Effects of Shear Detachment on Biomass Growth and In Situ Bioremediation   总被引：1，自引：0，他引：1  

Thomas R. MacDonald  Peter K. Kitanidis  Perry L. McCarty  Paul V. Roberts 《Ground water》1999,37(4):555-563

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CMEs in the Heliosphere: I. A Statistical Analysis of the Observational Properties of CMEs Detected in the Heliosphere from 2007 to 2017 by STEREO/HI-1     

R. A. Harrison  J. A. Davies  D. Barnes  J. P. Byrne  C. H. Perry  V. Bothmer  J. P. Eastwood  P. T. Gallagher  E. K. J. Kilpua  C. Möstl  L. Rodriguez  A. P. Rouillard  D. Odstrčil 《Solar physics》2018,293(5):77

We present a statistical analysis of coronal mass ejections (CMEs) imaged by the Heliospheric Imager (HI) instruments on board NASA’s twin-spacecraft STEREO mission between April 2007 and August 2017 for STEREO-A and between April 2007 and September 2014 for STEREO-B. The analysis exploits a catalogue that was generated within the FP7 HELCATS project. Here, we focus on the observational characteristics of CMEs imaged in the heliosphere by the inner (HI-1) cameras, while following papers will present analyses of CME propagation through the entire HI fields of view. More specifically, in this paper we present distributions of the basic observational parameters – namely occurrence frequency, central position angle (PA) and PA span – derived from nearly 2000 detections of CMEs in the heliosphere by HI-1 on STEREO-A or STEREO-B from the minimum between Solar Cycles 23 and 24 to the maximum of Cycle 24; STEREO-A analysis includes a further 158 CME detections from the descending phase of Cycle 24, by which time communication with STEREO-B had been lost. We compare heliospheric CME characteristics with properties of CMEs observed at coronal altitudes, and with sunspot number. As expected, heliospheric CME rates correlate with sunspot number, and are not inconsistent with coronal rates once instrumental factors/differences in cataloguing philosophy are considered. As well as being more abundant, heliospheric CMEs, like their coronal counterparts, tend to be wider during solar maximum. Our results confirm previous coronagraph analyses suggesting that CME launch sites do not simply migrate to higher latitudes with increasing solar activity. At solar minimum, CMEs tend to be launched from equatorial latitudes, while at maximum, CMEs appear to be launched over a much wider latitude range; this has implications for understanding the CME/solar source association. Our analysis provides some supporting evidence for the systematic dragging of CMEs to lower latitude as they propagate outwards.  相似文献   

Downstream migration of Geotria australis juveniles in the lower Waikato River (note)     

Perry W. Empson  Adrian S. Meredith 《新西兰海洋与淡水研究杂志》2013,47(4):643-644

Juvenile migrants of Geotria australis were caught from July to early August 1986 in plankton nets set in the lower Waikato River. Migration occurred only at night and mainly mid‐river at the surface. The mean lengths and weights (± 95%c.i.) were 107.75 ± 3.98 mm and 0.94 ± 0.08 g respectively.  相似文献