A classification of lunar rock and glass samples using theG-mode central method     

R. Bianchi  J. C. Butler  A. Coradini  A. I. Gavrishin 《Earth, Moon, and Planets》1980,22(3):305-322

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Noise in pressure transducer readings produced by variations in solar radiation     

Cain SF  Davis GA  Loheide SP  Butler JJ 《Ground water》2004,42(6-7):939-944

Variations in solar radiation can produce noise in readings from gauge pressure transducers when the transducer cable is exposed to direct sunlight. This noise is a result of insolation-induced heating and cooling of the air column in the vent tube of the transducer cable. A controlled experiment was performed to assess the impact of variations in solar radiation on transducer readings. This experiment demonstrated that insolation-induced fluctuations in apparent pressure head can be as large as 0.03 m. The magnitude of these fluctuations is dependent on cable color, the diameter of the vent tube, and the length of the transducer cable. The most effective means of minimizing insolation-induced noise is to use integrated transducer-data logger units that fit within a well. Failure to address this source of noise can introduce considerable uncertainty into analyses of hydraulic tests when the head change is relatively small, as is often the case for tests in highly permeable aquifers or for tests using distant observation wells.  相似文献   

Seasonal cycling of arsenic species in a stratified,microtidal estuary (Huon River,Tasmania)     

Alison?M.?FeatherstoneEmail author  Edward?C.?V.?Butler  Barry?V.?O'Grady 《Estuaries and Coasts》2004,27(1):18-35

A detailed study of arsenic cycling in the Huon estuary, south-east Tasmania, was undertaken October 1996–September 1998. Arsenic species data were obtained during eight 3-monthly spatial surveys, and a time-series study at a single site in the estuary over a 7-mo period. The data have been correlated with other chemical measurements, including nutrients, salinity, and dissolved oxygen, and also with biological information about the microalgal species present. In the Huon estuary, arsenic cycling is almost entirely biologically influenced. The seasonal cycle of reduced, methylated, and hydride refractory arsenic species was similar to that found in other temperate estuaries of the Northern hemisphere, with greatest production occurring during summer months. Inorganic arsenic concentrations in the Huon River were very low [As(V+III): 0.023–0.057 μg l⁻¹], even when compared with other pristine systems. Concentrations at the seaward end of the estuary were typical of those found in unpolluted coastal seawater. The behavior of As(V+III) in the estuary was nearly conservative in all surveys except those conducted during summer (February), when significant depletion was observed at higher salinity. During these surveys, up to 60% of inorganic arsenic was apparently depleted from the water column with only a small proportion (20–25%) recycled as methylated and UV-labile arsenic species. This was particularly the case in a high salinity side-arm of the estuary, Port Cygnet. The extent of inorganic arsenic depletion correlated with cell numbers of the phytoplanktonPseudo-nitzschia. The fate of the missing inorganic arsenic is unclear, but the co-existence ofPseudo-nitzschia blooms with commercial mussel leases in Port Cygnet could provide one explanation for the loss.  相似文献   

On the Perna Bed and the Weald Clay at Reigate: With report of excursion to Reigate,Saturday, February 4th, 1922     

Gerard W. Butler 《Proceedings of the Geologists' Association. Geologists' Association》1922,33(4):313-318

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Normal paraffin profiles of pelagic tar samples from the marmap survey     

James N. Butler  Judith C. Harris 《Marine Chemistry》1975,3(1):1-7

Pelagic tar samples from twenty stations on cruises of the research vessels ALBATROSS IV (72-6) and DELAWARE II (72-19) were analyzed by gas chromatography to obtain semi-quantitative profiles of normal paraffins in the range from C₁₀ to C₃₅ and a qualitative indication of the relative amount of other compounds having a volatility in that same range. These samples are essentially all weathered residues of waxy paraffinic crude oils, and are similar (with respect to the parameters measured) to numerous samples collected in the Sargasso Sea near Bermuda.  相似文献   

The action of heavy metals on the gametes of the marine mussel, Mytilus edulis (L.)—III. The effect of applied copper and zinc on sperm motilityin relation to ultrastructural damage and intracellular metal localisation     

M.J. Earnshaw  S. Wilson  H.B. Akberali  R.D. Butler  K.R.M. Marriott 《Marine environmental research》1986,20(4)

Treatment of Mytilus edulis sperm with external concentrations of copper or zinc (0-1-3-3mM) causes a decrease in motility in which zinc is more inhibitory than copper. Zinc also appeared to cause more extensive mitochondrial damage, as revealed by transmission electron microscopy, than did treatment with copper. The relationship between sperm motility and respiration in the presence of the various heavy metal concentrations used indicates that the depression of sperm motility can be explained largely on the basis of respiratory inhibition. However, zinc produces a less pronounced effect on sperm motility than on r respiration.X-ray microanalysis of thick sections of fixed treated sperm showed that copper accumulation occurs in the acrosomes, mitochondria and nuclei, whereas zinc is found in the acrosomes and in mitochondrial granules in association with calcium and phosphorus. No evidence was obtained for zinc accumulation in the nuclei. Treatment with either copper or zinc resulted in considerable reductions of bound calcium and phosphorus in both the acrosomes and mitochondria. It is suggested that the heavy metal ions cause an increase in the permeability of the organelle membranes to calcium and phosphorus.It is concluded that the less marked effect of zinc on sperm motility as compared to respiration may be due to an increase in the cytosolic free calcium concentration which, in turn, may stimulate the flagellar contractile apparatus.  相似文献   

Benthic fluxes of nitrogen in the tidal reaches of a turbid, high-nitrate sub-tropical river     

Perran L. M. Cook  Bradley D. Eyre  Rhys Leeming  Edward C. V. Butler   《Estuarine, Coastal and Shelf Science》2004,59(4):675-685

Benthic fluxes of dissolved inorganic nitrogen (NO₃⁻ and NH₄⁺), dissolved organic nitrogen (DON), N₂ (denitrification), O₂ and TCO₂ were measured in the tidal reaches of the Bremer River, south east Queensland, Australia. Measurements were made at three sites during summer and winter. Fluxes of NO₃⁻ were generally directed into the sediments at rates of up to −225 μmol N m⁻² h⁻¹. NH₄⁺ was mostly taken up by the sediments at rates of up to −52 μmol N m⁻² h⁻¹, its ultimate fate probably being denitrification. DON fluxes were not significant during winter. During summer, fluxes of DON were observed both into (−105 μmol m⁻² h⁻¹) and out of (39 μmol m⁻² h⁻¹) the sediments. Average N₂ fluxes at all sampling sites were similar during summer (162 μmol N m⁻² h⁻¹) and winter (153 μmol N m⁻² h⁻¹). Denitrification was fed both by nitrification within the sediment and NO₃⁻ from the water column. Sediment respiration rates played an important role in the dynamics of nitrification and denitrification. NO₃⁻ fluxes were significantly related to TCO₂ fluxes (p<0.01), with a release of NO₃⁻ from the sediment only occurring at respiration rates below 1000 μmol C m⁻² h⁻¹. Rates of denitrification increased with respiration up to TCO₂ fluxes of 1000 μmol C m⁻² h⁻¹. At sediment respiration rates above 1000 μmol C m⁻² h⁻¹, denitrification rates increased less rapidly with respiration in winter and declined during summer. On a monthly basis denitrification removed about 9% of the total nitrogen and 16% of NO₃⁻ entering the Bremer River system from known point sources. This is a similar magnitude to that estimated in other tidal river systems and estuaries receiving similar nitrogen loads. During flood events the amount of NO₃⁻ denitrified dropped to about 6% of the total river NO₃⁻ load.  相似文献   

Why Hell Stinks of Sulfur: Mythology and Geology of the Underworld          下载免费PDF全文

David R. Butler 《Geographical review》2017,107(4):e44-e46

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Azimuthal structures in the wind and chromosphere of the herbig Ae star ab aur. preliminary results from the MUSICOS 1992 campaign     

C. Catala  T. Böhm  J. -F. Donati  T. Simon  A. Welty  E. Houdebine  L. Huang  S. Jiang  D. Zhai  J. Neff  B. H. Foing  K. Ghosh  J. Butler  A. Collier-Cameron  J. Baudrand  J. Czarny  B. Carter  D. Rees  M. Semel  G. Cutispoto  M. Rodonò 《Solar physics》1994,155(1):185-193

MUSICOS (for MUlti-SIte COntinuous Spectroscopy) is an international project to facilitate and organize world-wide multi-site campaigns in high resolution spectroscopy, in view of obtaining a complete time coverage of various types of variable stellar phenomena.In the framework of this project a vast spectroscopic campaign was organized in December 1992, involving 8 sites well distributed in longitude around the Earth. The observations concerned three scientific programs, among which was the study of azimuthal structures in the wind and chromosphere of the pre-Main-Sequence Herbig Ae star AB Aur.The Hei 5876 line of AB Aur, which is formed in the expanding chromosphere of this star, in the innermost parts of its wind, was monitored at a resolution of 30000, nearly continuously for about 4 days. A spectacular variability of this line was discovered, the profile changing from pure emission to a composite profile including a deep absorption component in the course of a few hours. This variability can be the signature of azimuthal structures in the wind of AB Aur.We present the data collected during the campaign, and discuss possible interpretations of the spectacular variations of the Hei 5876 line.ESA/VILSPAUniversity of British Columbia CanadaBased on observations obtained during the MUSICOS 92 MUlti-SIte COntinuous Spectroscopic campaign from the National Solar Observatory McMath/Pierce 1.5 m, University of Hawaii 2.2 m, Beijing Observatory Xinglong 2.16 m, La Palma 4.2 m William Herschel Telescope, and Observatoire de Haute-Provence 1.52 m telescopes.Presented at the Cosmic Winds and the Heliosphere Conference in Tucson, Arizona, U.S.A., October 18–22, 1993.Visiting Astronomer, Kitt Peak National Observatory, National Optical Astronomy Observatories, which is operated by the Association of Universities for Research in Astronomy, Inc., under cooperative agreement with the National Science Foundation.Visiting Astronomer National Solar Observatory, National Optical Astronomy Observatories, which is operated by the Association of Universities for Research in Astronomy, Inc., under cooperative agreement with the National Science Foundation.  相似文献   

The Effects of Altering Seagrass Canopy Height on Small, Motile Invertebrates of Shallow Mediterranean Embayments     

R. M. Connolly  A. J. Butler 《Marine Ecology》1996,17(4):637-652

Abstract. The height of seagrass canopy was manipulated in experimental plots in meadows of the fine-leaves seagrass Cymodocea nodosa at two sites in the Mediterranean Sea, la Lagune du Brusc, Iles des Embiez near Toulon, and I'Etang de Diana on Corsica. Epifauna (small motile invertebrates associated with the seagrass canopy or sediment surface), was collected at night at both sites, and during the day at Diana only, from three treatments: full seagrass canopy, reduced canopy, and canopy removed entirely. Although epifaunal assemblages from the two sites were different, treatment modification had the same effect at both sites when analysed using multivariate ordinations. Abundance and biomass of total epifauna and of key taxa were all reduced in line with decreasing seagrass cover at both sites at night. The effects of treatment modification on epifauna during the day showed the same trend but were of greater magnitude, both for assemblages and for total abundance and biomass. At both sites and at both times, the fauna of plots from which seagrass had been cut tended to be dominated by animals of higher biomass than the fauna of plots with full canopy. Epifauna form the major dietary component of small fish inhabiting shallow, sheltered embayments. These results are therefore consistent with a model in which reduced abundance of fish associated with reduced seagrass canopy is explained by a reduction in food availability.  相似文献