On the equivalence of two methods for computing partial derivatives of seismic waveforms—II. Laterally homogeneous initial model     

Robert J. Geller  Tatsuhiko Hara  Seiji Tsuboi 《Geophysical Journal International》1990,102(2):499-502

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Erratum     

J.P. Phillips 《Astrophysics and Space Science》2004,291(1):97-97

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Ca ii K interstellar observations towards early-type disc and halo stars – distances to intermediate- and high-velocity clouds     

J. V. Smoker  B. B. Lynn  W. R. J. Rolleston  H. R. M. Kay  E. Bajaja  W. G. L. Poppel  F. P. Keenan  P. M. W. Kalberla  C. J. Mooney  P. L. Dufton  R. S. I. Ryans 《Monthly notices of the Royal Astronomical Society》2004,352(4):1279-1290

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Instrument development to search for biomarkers on mars: Terrestrial acidophile, iron-powered chemolithoautotrophic communities as model systems     

V. Parro  J.A. Rodríguez-Manfredi  C. Compostizo  E. Vez  M. Moreno-Paz  P. Fernández-Calvo  J. Pérez-Mercader  J. Gómez-Elvira 《Planetary and Space Science》2005,53(7):729-737

Recent findings by the MER rover opportunity confirming the presence of iron minerals that can only be formed in the presence of water emphasize the study of analogous environments to Mars on Earth. The study of chemolithoautotrophic communities living in acidic iron-rich habitats is highly relevant in order to identify Mars analog environment-specific biomarkers. Iron oxidizing bacteria like Leptospirillum ferrooxidans and Acidithiobacillus ferrooxidans have ways of life for which it is feasible to identify a past or present hypothetical niche on Mars. We have developed a strategy for biomarker identification based on: (i) search for biosignatures on acid and metal-rich environments; (ii) development of an immunosensor microarray; and (iii) integration into an instrument for autonomous and remote operation. The instrument that we have built, called Signs Of LIfe Detector (SOLID), is capable of processing a variety of samples for the detection of specific biomarkers. Antibodies against several bacterial strains have been developed and tested in a microarray biosensor on SOLID. Tests with field samples have been successfully performed, allowing the detection of L. ferrooxidans, A. ferrooxidans present in sediment samples.  相似文献   

Is the transition impact to post‐impact rock complete? Some remarks based on XRF scanning,electron microprobe,and thin section analyses of the Yaxcopoil‐1 core in the Chicxulub crater     

J. SMIT  S. VAN DER GAAST  W. LUSTENHOUWER 《Meteoritics & planetary science》2004,39(7):1113-1126

Abstract The transition from impact to post‐impact rocks in the Yaxcopoil‐1 (Yax‐1) core is marked by a 2 cm‐thick clay layer characterized by dissolution features. The clay overlies a 9 cm‐thick hardground, overlying a 66 cm‐thick crossbedded unit, consisting of dolomite sandstone alternating with thin micro‐conglomerate layers with litho‐ and bioclasts and the altered remains of impact glass, now smectite. The micro‐conglomerates mark erosion surfaces. Microprobe and backscatter SEM analysis of the dolomite rhombs show an early diagenetic, complex‐zoned, idiomorphic overgrowth, with Mn‐rich zones, possibly formed by hot fluids related to cooling melt sheet in the crater. The pore spaces are filled with several generations of coelestite, barite, K‐feldpar, and sparry calcite. XRF core scanning analysis detected high Mn values in the crossbedded sediments but no anomalous enrichment of the siderophile elements Cr, Co, Fe, and Ni in the clay layer. Shocked quartz occurs in the crossbedded unit but is absent in the clay layer. The basal Paleocene marls are strongly dissolved and do not contain a basal Paleocene fauna. The presence of a hardground, the lack of siderophile elements, shocked quartz, or Ni‐rich spinels in the clay layer, and the absence of basal Paleocene biozones P0 and Pa all suggest that the top of the ejecta sequence and a significant part of the lower Paleocene is missing. Due to the high energy sedimentation infill, a hiatus at the top of the impactite is not unexpected, but there is nothing in the biostratigraphy, geochemistry, and petrology of the Yax‐1 core that can be used to argue against the synchroneity of the end‐Cretaceous mass‐extinctions and the Chicxulub crater.  相似文献   

The brine shrimp (Artemia parthenogenetica) as encapsulation organism for prophylactic chemotherapy of fish and prawn     

Cao Ji-xiang  Bian Bo-zhong  Li Ming-ren 《中国海洋湖沼学报》1996,14(2):183-188

Brine shrimp (Artemia parthenogenetica) which had ingested three water-insoluble antibacterial drugs i.e. sulfadiazine(SD), oxytetracycline (OTC) and erythromycin estolate (ERY-Es) were fed toTilapia and Mysis IIIof Penaeus orientalis K. The drug contents in the predators were then determined. After administration of drugs toTilapia and Mysis III, through the bio-encapsulation of the brine shrimp, efficacious therapeutical concentration of OTC and ERY-Es (but not SD) in the predators could be reached and maintained for more than 8 hours.  相似文献   

Pore structure of sheared coals and related coalbed methane     

Huoyin Li  Yujiro Ogawa 《Environmental Geology》2001,40(11-12):1455-1461

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Research on the effect of sludge fertilizer on farmland and the safety of heavy metals in a karst area     

Qinglin Xie  Xuehong Zhang  Dunqiu Wang  Jincheng Li  Yiyong Qin  Yudao Chen 《Environmental Geology》2001,41(3-4):352-357

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Prospects for astrometry with the Hubble Space Telescope     

W. H. Jefferys  G. F. Benedict  P. D. Hemenway  P. J. Shelus  R. L. Duncombe 《Celestial Mechanics and Dynamical Astronomy》1985,37(3):299-305

The Hubble Space Telescope (HST), a large optical telescope having an aperture of 2.4 meters and a length of 8.8 meters, is being developed by the National Aeronautics and Space Administration. This telescope will be placed into earth orbit by the space shuttle. Astrometric observations with the HST are made using a Fine Guidance Sensor which is capable of measuring the position of one object relative to another with an accuracy of ±0.002 arcseconds. The astrometric user of HST will be provided with an Astrometric Data Reduction Software package (ADRS). The variety of astrometric problems to be investigated with HST is discussed.  相似文献   

Self-similar solutions for the blast wave problem in radiative gasdynamics,I     

J. B. Singh  K. S. Singh 《Astrophysics and Space Science》1985,111(1):79-85

Similarity solutions, describing the flow of a perfect gas behind spherical shock waves, are investigated including the radiation heat flux. The shock is assumed to be propagating in a medium at rest. Shock radius varies exponentially with time and density is inversely proportional to fifth power of the shock radius immediately ahead of the shock front.  相似文献