The transport of bacteria in the sediments of a temperate marsh     

Parke A. Rublee  Susan M. Merkel  Maria A. Faust 《Estuarine, Coastal and Shelf Science》1983,16(5):501-509

The number of bacteria in sediments, interstitial water and overlying tidal water of an oligohaline marsh system are about 10⁹, 10⁶ and 10⁶ cells cm^?3, respectively. Average cell size in the overlying water (about 0·06 μm³), is much smaller than that in sediments and interstitial water (about 0·18 μm³). Most bacterial cells in sediments are bound to sediment particles and less than 1% of the cells were displaced by percolating water through sediment columns. Concentration of bacteria in flooding tidal waters is generally higher than that in ebbing waters. Movement of bacterial biomass does not appear to be a significant mechanism of particulate organic transport in marsh sediments and marsh sediments do not appear to be a source of suspended bacteria for estuaries.  相似文献   

THE NATIONAL PATTERN OF AIRBORNE TOXIC RELEASES   总被引：1，自引：0，他引：1  

Susan L. Cutter  William D. Solecki 《The Professional geographer》1989,41(2):149-161

Incident-specific data reveal the spatial patterns of two major classes of acute toxic airborne releases in the United States (1982–86): rural agricultural and urban industrial. Rural (primarily truck transport) incidents dominate the distribution in the western US, while rail incidents and fixed site incidents dominate in the east. Using a combination of cartographic and statistical analyses, risk and mitigation measures were calculated to identify high-hazard and low-hazard states. Risk factors, primarily numbers of chemical firms and rail miles per state, best predict the frequency of incidents and their resulting spatial pattern.  相似文献   

The NASA-ARC 10/20 micron camera     

T. L. Roellig  R. Cooper  L. K. Deutsch  C. Mccreight  M. McKelvey  Y. J. Pendleton  F. C. Witteborn  L. Yuen  T. McMahon  M. W. Werner 《Experimental Astronomy》1994,3(1-4):173-174

A new infrared camera (AIR Camera) has been developed at NASA-Ames Research Center for observations from ground-based telescopes. The heart of the camera is a Hughes 58 × 62 pixel Arsenic-doped Silicon detector array that has the spectral sensitivity range to allow observations in both the 10 and 20 micron atmospheric windows.The U.S. Government right to retain a non-exclusive, royalty-free licence in and to any copyright is acknowledged.  相似文献   

A geophysical study of the Rhinegraben — I. Kinematics and geothermics     

Dietrich Werner  Hans-Gert Kahle 《Geophysical Journal International》1980,62(3):617-629

  相似文献   

Post-shock temperatures in minerals   总被引：1，自引：0，他引：1  

Susan A. Raikes  Thomas J. Ahrens 《Geophysical Journal International》1979,58(3):717-747

  相似文献   

Mussels as sentinels     

Susan Peterson  Bruce Tripp 《Marine Policy》1984,8(3):291-292

Mussel Watch II, ‘Chemical changes in the coastal zone’, Honolulu, Hawaii, 7–11 November 1983  相似文献   

The JPL deep-well mid-infrared array camera     

Michael E. Ressler  Michael W. Werner  Jeff Van Cleve  Helen A. Chou 《Experimental Astronomy》1994,3(1-4):277-280

We describe the development of a mid-infrared camera intended for use at the Palomar 5-m telescope and at the NASA Infrared Telescope Facility. The camera is based on Rockwell's HF-16 128×128 Si:As BIB array. This array is unusual in that it has a well depth of approximately 30 million electrons; this will allow the use of traditional broadband astronomical filters (N and Q) while keeping a reasonable field-of-view. Measured array performance indicates that it has a read noise of 1100 electrons and shows non-linearities of <1% up to 65% of full well. In this paper, we discuss the array and its operating characteristics and we give a brief overview of the camera design.National Research Council research associate at JPLSummer Undergraduate Research Fellow at JPL  相似文献   

On the validity of weak particle-field interaction theory for the description of cosmic-ray particle diffusion in random magnetic fields     

Werner Alpers  Klaus Hasselmann  Jörn Kunstmann 《Astrophysics and Space Science》1978,58(2):259-271

  相似文献   

Re-inventing government: Emerging geographies in the aftermath of the 1984 reforms in New Zealand     

Gary L. Hermansson  Susan B. Webb 《GeoJournal》2004,59(2):91-92

Introduction

Re-inventing government: Emerging geographies in the aftermath of the 1984 reforms in New Zealand  相似文献   

End-member ferrian kanonaite: an andalusite phase with one Al fully replaced by (Mn,Fe)<Superscript>3+</Superscript> in a quartz vein from the Ardennes mountains,Belgium, and its origin     

Werner?SchreyerEmail author  Heinz-Jürgen?Bernhardt  André-Mathieu?Fransolet  Thomas?Armbruster 《Contributions to Mineralogy and Petrology》2004,147(3):276-287

Kanonaite, with compositions plotting on the join Mn³⁺AlSiO₅–Fe³⁺AlSiO₅, was discovered in a late quartz vein of the Le Coreux metamorphic manganese deposit. A typical structural formula is (Mn³⁺_3.69Fe³⁺_0.36)Al_3.95Si_4.00O₂₀, representing maximum solid solution within the system Al₂SiO₅–Mn₂SiO₅–Fe₂SiO₅. Refractive indices are =1.777; =1.855. The end-member compositions form the outermost, latest products in zoned crystals ranging to less manganiferous kanonaite. A crystal structure determination of a Mn-rich kanonaite confirms that about 96% of all the Mn³⁺ present is located in the strongly Jahn-Teller-distorted octahedron of the andalusite-type structure. Combining all relevant mineral-chemical and petrological data available on the deposit, a speculative model is presented in which kanonaite crystals with successively higher Mn³⁺ contents form during decreasing temperatures in the course of the anticlockwise PTt path of extensional metamorphism. Kaolinite occurring in zones within composite kanonaite porphyroblasts of adjacent phyllites is regarded here as by-product of a continuous retrograde breakdown reaction of less manganiferous kanonaite. In places, kanonaite was peripherally replaced by muscovite and Mn- and Fe-oxides.Editorial responsibility: J. HoefsDedicated to the late Dr. H.S. Yoder, Jr.  相似文献