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81.
Ohne Zusammenfassung 相似文献
82.
Zusammenfassung Es wird über Erfahrungen mit einem früher an dieser Stelle beschriebenen automatischen Kondensationskernzähler berichtet und speziell die Abhängigkeit der gemessenen Kernzahl von Expansionsgrad, Temperatur und relativer Feuchtigkeit untersucht, sowie die Einstellung einer konstanten Empfindlichkeit beschrieben.r>r>r>r>Mit 6 Textabbildungen. 相似文献
Summary Experiments are reported with the automatic condensation nuclei counter, which has already been described in this review. Adjustment for a constant sensitivity is described. The dependence of the number of nuclei upon the degree of expansion, temperature and relative humidity is especially studied.
Résumé L'article rapporte des expériences faites avec un compteur automatique de noyaux de condensation, qui auparavant déjà a été décrit dans cette revue. Il examine en particulier la dépendance du nombre des noyaux mesuré du degré d'expansion, de la température et de l'humidité relative et décrit aussi la mise au point d'une sensibilité constante.
83.
The amplitude response of a LCR gravimeter with the SRW-E feedback was determined on a vertical vibrating platform. The ink-pen recorder was connected parallel with the digital voltmeter input to obtain an analog response of the gravimeter to the harmonic motion of the base with a peak-to-peak amplitude of 10 rc="/content/p56043w52n414506/xxlarge956.gif" alt="mgr" align="MIDDLE" BORDER="0">m and periods excited in an interval of 4 - 10 s as by the ground motion of meteorological microseisms, and in the interval 10 -100 s as by surface waves of distant strong earthquakes.
In the first interval, an unexpected maximum of the amplitude response was observed with the double amplitude of apparent 6,5 rc="/content/p56043w52n414506/xxlarge956.gif" alt="mgr" align="MIDDLE" BORDER="0">Gal (6.5 × 10
–8
m/s
2
) at a period of 4.8 s, and a baseline shift with the amplitude of–64rc="/content/p56043w52n414506/xxlarge956.gif" alt="mgr" align="MIDDLE" BORDER="0">Gal was observed at the same period. The value of this direct component cannot be separated from the effect of the Earth's gravity field. In the second interval, the amplitude response of the gravimeter displayed one expected maximum at a period of 40 s with the double amplitude of 8.1rc="/content/p56043w52n414506/xxlarge956.gif" alt="mgr" align="MIDDLE" BORDER="0">Gal. At the usual level of microseisms with a peak-to-peak amplitude of up to 2 rc="/content/p56043w52n414506/xxlarge956.gif" alt="mgr" align="MIDDLE" BORDER="0">m the fluctuation of the gravimeter on the direct baseline shifted by –4.9 rc="/content/p56043w52n414506/xxlarge956.gif" alt="mgr" align="MIDDLE" BORDER="0">Gal was estimated at 1 rc="/content/p56043w52n414506/xxlarge956.gif" alt="mgr" align="MIDDLE" BORDER="0">Gal. With typical Rayleigh surface waves with periods of 20 s and double amplitudes of up to 100 rc="/content/p56043w52n414506/xxlarge956.gif" alt="mgr" align="MIDDLE" BORDER="0">m, the fluctuation reached 67 rc="/content/p56043w52n414506/xxlarge956.gif" alt="mgr" align="MIDDLE" BORDER="0">Gal. 相似文献
84.
Mathieu Bringer Michel Boër Cedric Peignot Gérard Fontan Colette Mercé 《Experimental Astronomy》2001,12(1):33-48
We have developped a new method for the scheduling ofastronomical automatic telescopes, in the framework of theautonomous TAROT instrument. The MAJORDOME software canhandle a variety of observations, constrained, periodic,etc., and produces a timeline for the night, which may bemodified at any time to take into account the specificconditions of the night. The MAJORDOME can also handletarget of opportunity observations without delay. 相似文献
85.
Studia Geophysica et Geodaetica - 相似文献
86.
J.?DostalEmail author J.?Vozár J.?D.?Keppie D.?Hovorka 《International Journal of Earth Sciences》2003,92(1):27-35
The 1,500- to 2,000-m-thick Permian volcano-sedimentary Malu?iná Formation of the uppermost nappe of the Central Western Carpathians (a segment of the Alpine-Carpathian orogenic belt) occurs in several fault blocks distributed across Slovakia. This unit is a part of a post-Variscan overstep suite that followed accretion of the Gothic terranes to Laurussia. It consists of three upward-fining megacycles of semi-arid/arid, fluvial-lacustrine clastic redbeds and local dolomites and evaporites. Abundant intercalated volcanic rocks are predominantly mafic lava flows; volcaniclastic rocks and dykes are subordinate. Felsic rocks are represented by rare volcaniclastics and dykes. Compositionally, the mafic rocks are rift-related continental tholeiites with enriched light REE patterns having (La/Yb)n ratios between 2 and 5.5 and with mantle-normalized patterns characterized by negative Nb-Ta anomalies. The rocks were derived from subcontinental lithospheric mantle and were affected by crustal contamination. It is inferred that the volcanism of the Malu?iná Formation formed in a Basin and Range tectonic setting in which rifting followed collision of the Palaeo-Tethys ridge with the trench bordering southern Laurussia. This model can be applied to other Permian volcanic suites of rift basins in the Eastern Alps and Carpathians over a strike-length of about 1,000 km, which indicates the width of the slab window. 相似文献
87.
Bohdan Kíbek Ivana Sýkorov Jan Paava Vladimír Machovi
《International Journal of Coal Geology》2007,72(3-4):240-256
Marine black shales of the Lower Cambrian Niutitang Formation in southern China host Mo–Ni–platinum group elements (PGE) mineralization confined to a phosphate- and pyrite-rich stratiform body (max. 20-cm thick). The H/C atomic ratio, carbon isotopic composition, FTIR spectra of bulk organic matter, and spectra of extractable part of organic matter indicate similar sources and thermal evolution of organic matter in barren and mineralized black shales.The morphology and relative abundance of organic particles in barren and mineralized shales are different. In barren black shales, organic particles comprise only elongated bodies and laminae 2–10 μm across or elongated larger bodies (> 10 μm) with Rmax = 2.96–5.21% (Type I particles). Mineralized black shales contain Type I particles in rock matrix (90–95 vol%), small veinlets or irregular organic accumulations (Type II particles, 1–5 vol%) that display weak to well developed mosaic texture and a variable reflectance (Rmax = 3.55–8.65%), and small (< 1 to 5 μm) rounded or irregular Type III organic particles (1–4 vol%) distributed within phosphate nodules and sulphide rip-up clasts. Type III particles show similar reflectance as particles of Type I in rock matrix. Type I particles are interpreted as remnants of in situ bacterially reworked organic matter of cyanobacteria/algal type, Type II as solidified products or oil-derived material (migrabitumen), and Type III particles as remnants of original organic matter in phosphatized or sulphidized algal/microbial oncolite-like bodies. Equivalent vitrinite reflectances of Type I and III particles in barren and mineralized rocks are similar and correspond to semi-anthracite and anthracite. Micro-Raman spectra of organic particles in rocks display a wide belt in the area of 1600 cm− 1 (G belt) and approximately the same belt in the area of 1350 cm− 1 (D belt). The ratio of integrated areas of the two belts correlate with Rmax values.The Mo–Ni–PGE mineralized body is interpreted as to represent a remnant of phosphate- and sulphide-rich subaquatic hardground supplied with organic material derived from plankton and benthic communities as well as with algal/microbial oncolite-like bodies that originated in wave-agitated, shallow-water, nearshore environment. 相似文献
88.
Gil Michard Christian Fouillac Daniel Grimaud Jérôme Denis 《Geochimica et cosmochimica acta》1981,45(7):1199-1207
A chemical model based on the equilibrium of water with quartz, albite, adularia, calcite, kaolinite or illite, and chlorite can explain the chemical composition of the main groups of hot springs in Massif Central. Temperature is the principal variable for determining this composition. Model temperatures generally agree with those given by classical cation geothermometers (t ? 135–150° C for Vichy. La Bourboule. Evaux and Châteauneuf; t ? 175–180° C for Chaudes Aigues and Saint Nectaire). The model fails to represent the composition of Mont Dore waters: the high temperatures given by classical geothermometers are considered doubtful. 相似文献
89.
Vladimír Kropáček Miroslav Krs Reviewer V. Bucha 《Studia Geophysica et Geodaetica》1975,19(3):261-274
Summary The paper is devoted to the study of the magnetic properties, of the volume magnetic susceptibility in a weak magnetic field, of the specific magnetic susceptibility in a strong magnetic field, of natural remanent magnetization and its stability in A.C. fields, and of the temperature dependence of magnetic susceptibility of natural Mn-oxides. Samples of pyrolusite, polianite, manganite, hausmannite, psilomelan and wad from different localities all over the world were studied; the measured values are statistically treated so that the given values are valid in general. Hausmannite displayed typical values of the magnetic susceptibility, different from the values of the other Mn-oxides. In general, many natural Mn-oxides contain heterogeneous admixtures of Fe-oxides, which are responsible for their ferromagnetic properties. A high degree of magnetic hardness, predetermining the minerals for palaeomagnetic research, was proved with many of the natural Mn-oxides. 相似文献
90.
Karel Holub Vladimír Tobyáš Karel Daviš Reviewer Z. Šimon 《Studia Geophysica et Geodaetica》1975,19(4):383-388
Summary The vertical component of ground displacement was measured at the Prague - Ruzynrc="/content/x286pk22754m6232/xxlarge283.gif" alt="ecaron" align="BASELINE" BORDER="0"> International Gravity Point in the frequency range of 1–300 Hz. The permanent noise, the vibrations caused by the observers during gravimetric observations and by the wind, as well as those due to normal operations at the airport, display maximum peak-to-peak amplitudes of 0.06 µm in the frequency range of 1–50 Hz; with a CG-2 gravimeter this is not detrimental to the accuracy of the observations. The taxiing of turbo-jet and jet aircraft and engine tests of aircraft generate vibrations in frequency ranges of 75–90 and 190–270 Hz. Their amplitudes, according to the results of laboratory tests published for various types of gravity meters (CG-2, GAK-PT, GVP-3, KVG), are of magnitudes which generate errors in tenths of mgl. 相似文献