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761.
Steeve Gréaux Denis Andrault Laurent Gautron Nathalie Bolfan-Casanova Mohamed Mezouar 《Physics and Chemistry of Minerals》2014,41(6):419-429
Compressibility of perovskite-structured Ca3Al2Si3O12 grossular (GrPv) was investigated at high pressure and high temperature by means of angle-dispersive powder X-ray diffraction using a laser-heated diamond anvil cell. We observed the Pbnm orthorhombic distortion for the pure phase above 50 GPa, whereas below this pressure, Al-bearing CaSiO3 perovskite coexists with an excess of corundum. GrPv has a bulk modulus (K 0 = 229 ± 5 GPa; \(K_{0}^{{\prime }}\) fixed to 4) almost similar to that reported for pure CaSiO3 perovskite. Its unit-cell volume extrapolated to ambient conditions (V 0 = 187.1 ± 0.4 Å3) is found to be ~2.5 % larger than for the Al-free phase. We observe an increasing unit-cell anisotropy with increasing pressure, which could have implications for the shear properties of Ca-bearing perovskite in cold slabs subducted into the Earth’s mantle. 相似文献
762.
763.
Andrey DARIN Ivan KALUGIN Natalya MAKSIMOVA Tatiana MARKOVICH Yakov RAKSHUN Dmitryi SOROKOLETOV Fedor DARIN Denis RAGOZIN 《《地质学报》英文版》2014,88(Z1):3-4
正1 Introduction Meromictic Shira Lake is a good represfor detail climate modeling due to its locainformation and annually laminated bottomsediment column of 155 cm in length wahammer corer in the deepest(24 m)central in 2009.2 Sample Preparations and Measuring 相似文献
764.
Gilbert VAN STAPPEN Thanh Toi HUYNH Nguyen Van Ho SUI Liying DENG Yuangao Peter BOSSIER 《《地质学报》英文版》2014,88(Z1):105-105
正The brine shrimp Artemia is often abundantly found in hypersaline environments.The larvae(‘nauplii’)hatching from its dormant embryos(‘cysts’)are a crucial live food item for the larval stages of fish and shrimp in aquaculture 相似文献
765.
766.
Theory and management of tropical fisheries. Edited by D. Pauly and G. I. Murphy. Proceedings of the ICLARM/CSIRO Workshop on the Theory and Management of Tropical Multispecies Stocks. 12–21 January 1981, Cronulla, Australia. 1982. 360 p. $US21.50 surface; hardbound. Animals of the estuary shore : illustrated guide and ecology. By Malcolm B. Jones, 1983. University of Canterbury publication No. 32. 162p., 140 figures, 11 keys. ISBN 0900–392–32–0 (soft cover, spiral bound). Price NZ$7.50. Numerical ecology. By L. Legendre and P. Legendre, 1983. Elsevier Scientific Publishing Company, Amsterdam. $US83.00. The control of oil pollution (revised edition). Edited by J Wardley‐Smith. Graham & Trot‐man Limited, London. 1983. 285 p., 98 figures, 17 tables. ISBN 0.86010 3382. £19.00/$US35.00. Physical oceanography in Australia. Edited by J. Imberger. Reprinted from the Australian Journal of Marine and Freshwater Research, Volume 34, 1–230, 1983. CSIRO, Melbourne 1983. 相似文献
767.
Hydrocarbons in coastal sediments from the Mediterranean sea (Gulf of Fos area, France) 总被引:2,自引:0,他引:2
Sedimentary hydrocarbons have been studied quantitatively and qualitatively in 11 coastal stations located in the Gulf of Fos (French Mediterranean coast). Hydrocarbon levels ranged from 10 to 260 mg kg(-1) sed. dry weight. A new parameter "NAR" (Natural n-alkane ratio) is proposed to evaluate the contribution of terrestrial inputs of hydrocarbons in the sediments. The origins of hydrocarbons are multiple: terrestrial inputs, biogenic, pyrolytic (industry emissions mainly steel and iron industries, ship and road traffic). Generally, the main source of contamination is not petroleum. Several ratios between parent polycyclic aromatic hydrocarbons show that the sources of hydrocarbons in the sediments are generally much more pyrolytic than petrogenic. 相似文献
768.
Influence of bioturbation by the polychaete Nereis diversicolor on the structure of bacterial communities in oil contaminated coastal sediments 总被引:1,自引:0,他引:1
Cuny P Miralles G Cornet-Barthaux V Acquaviva M Stora G Grossi V Gilbert F 《Marine pollution bulletin》2007,54(4):452-459
Patterns of change in the structure of bacterial communities monitored by ribosomal intergenic spacer analysis (RISA) in oil contaminated sediments inhabited or not by the marine polychaete Nereis diversicolor were studied during 45 days under laboratory conditions. Results supported by principal component analysis showed a marked response of the bacterial communities to the oil contamination and to the presence of N. diversicolor. Phylogenetic affiliation of specific RISA bands showed that, in the contaminated sediments, the presence of the marine polychaetes favoured the development of bacteria which may play an active role in natural bioremediation processes of oil polluted environments. 相似文献
769.
Denis Samyn Sean J. Fitzsimons Reginald D. Lorrain 《International Journal of Earth Sciences》2010,99(8):1849-1857
Structural analyses were conducted in the basal zone of an Antarctic glacier. The studied basal ice sequence was retrieved
from a 20-m-long subglacial tunnel dug at the margin of the glacier and is at the temperature of −17°C. For the first time,
rotating clast systems embedded within debris-rich ice were thin-sectioned using specially designed cutting techniques. The
observed structures reflect the occurrence of pervasive shearing at the base of the glacier, and can be used as shear sense
indicators. In addition, some of these structures provide evidence for the presence of thin liquid films at the time of formation
despite the marked freezing temperature of the ice. It is showed here that cautious analysis of deformation structures present
in debris-bearing ice may bring insights not only into the flow dynamics of the embedding matrix, but also into the behaviour
of the interstitial fluid network at the base of cold glaciers and ice sheets. 相似文献
770.
Geochemical study of clays used as barriers in landfills 总被引:1,自引:0,他引:1
This is a hydraulic and geochemical study on 2 materials: natural clay (AN) and a regenerated material made up of a sand-bentonite (SB) mixture. The hydraulic part allowed us to conclude that a 10% industrial bentonite content mixed with sand offers hydraulic properties that are similar to those of AN material and are lower than the required standards. The geochemical properties of both AN and SB matrixes are comparable with those of some of the synthetic leachates studied. Furthermore, the Langmuir model helped us to identify the adsorption capacities of both matrixes with the following selectivities: Pb > Cu > Cd > Zn. 相似文献