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521.
Ohne ZusammenfassungMit 2 Textabbildungen.  相似文献   
522.
The Canyonlands meteorite weighing 1,520 grams was found near the confluence of the Green and Colorado Rivers, Utah, near lat 38°11′N.; long 109°53′W. It is a shocked, brecciated H6 chondrite containing large black veins which do not differ in composition from the main chondritic mass. A black fusion crust remains on part of the meteorite.  相似文献   
523.
A preliminary analysis of the data from the UCLA magnetometer on board the Apollo 15 subsatellite indicates that remnant magnetization is a characteristic property of the Moon, that its distribution is such as to produce a rather complex pattern or fine structure, and that a detailed mapping of its distribution is feasible with the present experiment. The analysis also shows that lunar induction fields produced by transients in the interplanetary magnetic field are detectable at the satellite orbit so that in principle the magnetometer data can be used to determine the latitudinal and longitudinal as well as radial dependences of the distribution of electrical conductivity within the Moon. Finally, the analysis indicates that the plasma void or diamagnetic cavity which forms behind the Moon when the Moon is in the solar wind, is detectable at the satellite's orbit and that the flow of the solar wind near the limbs is usually rather strongly disturbed.Publication No. 981. Institute of Geophysics and Planetary Physics.  相似文献   
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The IronRefs database covers published research on remediation applications of zero-valent metals and is accessible at http://www.cgr.ese.ogi.edu/ironrefs/ . The rapid growth of ground water remediation applications of zero-valent metals is reflected in the rapid growth of this database, which exceeded 500 records in December 2001. This is much more complete coverage of this topic than can be obtained from any of the major commercial databases of the scientific literature. Specialized databases such as IronRefs, prepared by experts in a particular field, are becoming increasingly common on the Web and offer distinctive benefits over traditional options for keeping up with the literature in rapidly growing fields of science and engineering.  相似文献   
526.
An exact solution of the transport equation in radiative transfer for an axially symmetric Rayleigh scattering problem in semi-infinite planetary atmosphere both for emergent intensity and intensity at any optical depth has been derived with the help of the Laplace transform and the Wiener-Hopf technique, and by use of the constancy of net flux. Chandrasekhar's results for emergent intensity have been verified. New expressions for theH l andH r functions have been obtained.  相似文献   
527.
The radial brightness distribution of the Sun at 3.2 mm is recalculated for the 7 March, 1970 total solar eclipse by an improved method. The results from the first contact of the 30 June, 1973 total eclipse are also analyzed. Limb brightening is apparent for the 1970 eclipse when all four contacts are averaged. The 1973 eclipse indicates strong limb brightening, although the detailed shape differs from the 1970 eclipse.  相似文献   
528.
A catalogue of seismicity in Greece and adjacent areas   总被引:5,自引:0,他引:5  
Summary. A new earthquake catalogue for Greece has been formed to cover the instrumental period 1901–78, in particular 605 earthquakes for the period 1917–63 inclusive are relocated using first arrival data from the International Seismological Summary. These relocations incorporate macro-seismically and other well-controlled master events into an ensuing joint epicentre determination technique. The largest annual average shift is 165 km for 78 earthquakes during the decade after 1917, decreasing to 17 km for the later years 1957–63. Magnitudes are redetermined mainly using readings from the Swedish network and Uppsala since as early as 1908. Catalogue completeness exists for magnitudes around 5.5 for at least the last 60 years, but magnitudes of about 4.7 are completely reported only during the most recent 15 years.
The new epicentral positions lead to a better delineation of the seismic zones than has previously been achieved. The majority of shallow earthquakes are contained in a belt parallel to the Hellenic Arc which extends north into Albania, in the south-east the epicentral locations give a more diffuse extension of this zone into the west coast of Turkey. Depths of intermediate earthquakes along the Hellenic Arc tend to relocate to shallower depths, in the south-west part of Crete no earthquake focus deeper than 100 km is found, although in the south-eastern section of the arc a tendency to increased depths is observed. A second zone starts at Leukas Island in the west and extends through central Greece to near Volos on the east coast, where it divides into two branches, which are less well defined, but which eventually join the seismicity of western Turkey. A third zone follows the Saronikos and Corinth gulfs.  相似文献   
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530.
GEO LOGIC     
Let me begin by outlining the role of this column. It is aimed at European geoscientists who use personal computers. Rather than duplicating what is already discussed in the hundreds of computer magazines that can be found at any newsagent, I will concentrate on those products and services that have a particular application in the Earth Sciences. This is not to say that only those products with a specific Earth Science application will be discussed. Instead, anything that a practising geoscientist might find useful will be a candidate for review; a software package for compiling reference lists in the many styles demanded by different journals would be an example. The column will devote itself to products for IBM-PC and Mac users. I apologise in advance for the UK perspective offered in the first few articles; this reflects my ignorance of the European scene and the difficulties I have faced in overcoming it. I look forward to feedback from continental geoscientists who, I hope, will bring me up to date regarding the truly European picture.  相似文献   
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