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201.
202.
X. Bai T.K. Gaisser A. Karle K. Rawlins G.M. Spiczak Todor Stanev 《Astroparticle Physics》2006,25(6):361-367
The muon flux at the South Pole was measured for five zenith angles, 0°, 15°, 35°, 82.13° and 85.15° with a scintillator muon telescope incorporating ice Cherenkov tank detectors as the absorber. We compare the measurements with other data and with calculations. 相似文献
203.
204.
205.
F.Z. Feygin YU.P. Kurchashov V.A. Troitskaya K. Dobeš 《Planetary and Space Science》1985,33(3):271-273
A high resolution numerical sonagram of Pc-1 magnetic record has shown that single narrow lines of Pc-1 spectra produce lower frequency (“red-shifted”) satellite lines more than twice as often as their higher frequency (“violet”) counterparts. The violet satellites usually emerge only when at least two ancestor lines are present simultaneously. 相似文献
206.
This paper and subsequent Paper II are an investigation of the annihilation line formation in gamma-ray bursts based on the assumption of positron production in a strong magnetic field (because of one-photon absorption of hard gamma-quanta radiated in the neutron star hot polar spot). We discuss a two-photon annihilation line in this paper. It is shown that if the star magnetic field is greater than 3×1012 G, the relative flux in the line depends solely on the hardness of the continuum and is, as a rule, less than or about 10–20% of the total flux. This is consistent with the spectral data recorded by ‘Venera-11’ and ‘Venera-12’ space probes. The annihilation region formation above the hot polar spot is discussed, and positron density and annihilation region dimensions are estimated. 相似文献
207.
U–Th–Pb analyses of zircons from six granites and one metasediment collected in the accretionary Central belt of Taimyr, Arctic Siberia, demonstrate that Neoproterozoic (c. 900 Ma) granites intrude late Mesoproterozoic/early Neoproterozoic amphibolite facies metamorphic rocks. This is the first time in the Mamont–Shrenk region that Neoproterozoic ages have been recognized for these lithologies, previously thought to be Archaean/Palaeoproterozoic in age. The Mamont–Shrenk Terrane (MST) represents a Grenvillian age (micro?) continent intercalated with younger Neoproterozoic ophiolites during thrusting and accreted to the northern margin of the Siberian craton sometime before the late Vendian. Basement to the MST may have been derived from the Grenvillian belt of east Greenland. Viable tectonic reconstructions must allow for an active margin along northern Siberia (modern day coordinates) in the middle Neoproterozoic. 相似文献
208.
T. M. Will 《Mineralogy and Petrology》2001,72(1-3):229-247
Summary Geometric data of fault planes and fault plane lineations, together with the observed sense of shear on the slip planes,
were used to calculate paleostress tensors and fields responsible for the post metamorphic peak D3 and D4 deformation events
in the four Odenwald units sensu Krohe (1991). The paleostress fields were calculated using the method of Will and Powell (1991). As inferred from the paleostress analysis, the D3 strike-slip deformation west of the Otzberg fault zone was caused
by a, ± N-S directed, compressional regional stress field, with shallowly plunging σ1 axes and σ3 directions that plunge at shallow to moderate angles to the E or W; the calculated mean orientations are: σ1 06 → 350, σ2 77 → 234 and σ3 12 → 085. The B?llsteiner Odenwald east of the Otzberg fault zone was not affected by this stress field. This implies that
the Bergstr?sser and B?llsteiner Odenwald were spatially separated and formed independent crustal blocks during D3. The D4
faulting event is recognised in all areas investigated, even though most prominently in units III and IV, and juxtaposed the
Bergstr?sser and B?llsteiner Odenwald. This faulting episode was caused by a paleostress field with a steeply westerly plunging
σ1 axis and a shallowly southsoutheasterly plunging σ3 axis. The orientations of the principal stresses are: σ1 52 → 270, σ2 38 → 085 and σ3 06 → 174. With continued deformation from D3 to D4, there was a progressive change in the orientation of the stress field
indicating a change from a N-S compressional to extensional stress field, accompanied by the progressive development of strike-slip
faults and late normal faults. Paleostress field orientations in the Pfalz Forest, SW of the Odenwald, determined by Fl?ttmann and Oncken (1992) are very similar to those obtained for the Odenwald region and indicate a regionally consistent stress pattern in
the southwestern part of the Mid-German Crystalline Rise (MGCR) during strike-slip and normal faulting deformations.
Received July 8, 1999; revised version accepted March 28, 2000 相似文献
Zusammenfassung Paleostress-Tensor Analyse sp?ter Deformationsereignisse im Odenwald-Kristallin und ein Vergleich mit anderen Einheiten der Mitteldeutschen Kristallinzone, Deutschland Für die vier Odenwald-Einheiten im Sinne von Krohe (1991) wurden Pal?ostressfelder für die Blattverschiebungs- und Abschiebungsereignisse D3 und D4 mit der Methode von Will und Powell (1991) berechnet. Die Analyse ergibt, da? das regionale Spannungsfeld, das westlich der Otzberg-Zone im Bergstr?sser Odenwald zum D3-Ereignis führte, ein ± N-S gerichtetes kompressives Stresssfeld war. Die σ1-Achse f?llt flach nach N bzw. S ein, die σ3-Achse mit kleinen bis moderaten Winkeln nach E bzw. W; die berechneten Orientierungen der Hauptspannungsrichtungen sind: σ1 08 → 350, σ2 77 → 234 and σ3 12 → 085. Der B?llsteiner Odenwald, ?stlich der Otzberg-Zone, wurde von diesem Spannungsfeld nicht erfa?t. Dies impliziert, da? Bergstr?sser und B?llsteiner Odenwald w?hrend des D3-Ereignisses voneinander getrennt waren und separate Krusteneinheiten darstellten. Auswirkungen der D4-Deformation k?nnen im gesamten Untersuchungsgebiet erkannt werden, am st?rksten jedoch in den Einheiten III und IV. Dieses Ereignis wurde von einem Pal?ostressfeld mit einer steil nach W einfallenden σ1- und einer flach nach SSE einfallenden σ3-Achse verursacht und führte zum Zusammenschlu? von Bergstr?sser und B?llsteiner Odenwald. Die berechneten Orientierungen der Hauptspannungsrichtungen sind: σ1 52 → 270, σ2 38 → 085 und σ3 06 → 174. Die Rotation der Hauptspannungsrichtungen war mit einer ?nderung von einem kompressionalen N-S gerichteten (D3) hin zu einem extensionalen (D4) Stressfeld verbunden. Die erzielten Ergebnisse sind sehr ?hnlich mit Resultaten, die Fl?ttmann und Oncken (1992) im Pf?lzer Wald ermittelten. Dies weist auf ein regional übereinstimmendes Spannungsfeld im SW-Teil der Mitteldeutschen Kristallinzone hin.
Received July 8, 1999; revised version accepted March 28, 2000 相似文献
209.
V. P. Singh 《水文研究》2001,15(4):671-706
The history of the kinematic wave theory and its applications in water resources are traced. It is shown that the theory has found its niche in water resources and its applications are so widespread that they may well constitute what may be termed ‘kinematic wave hydrology’. Few theories have been applied in hydrology and water resources as extensively as the kinematic wave theory. This theory, however, is not without limitations and when it is applied they must be so recognized. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
210.
A numerical study of gas flow through a porous cometary mantle is presented. A kinetic model based on the well-known Test Particle Monte Carlo Method for the solution of rarefied gas dynamics problems is proposed. The physical model consists of two spatial plane regions: the condensed ice phase and a porous dust mantle. The structure of the porous dust layer is described as a bundle of cylindrical inclined channels not crossing each other. A vertical temperature gradient may exist across the dust mantle. The aim is to investigate how the characteristics of molecular flow depend on the capillary length, inclination angle, and temperature gradient. Examples illustrating a significant deviation of some results from equilibrium values are shown. In particular, the gas velocity distribution at both ends of the pore is strongly non-Maxwellian if there is an important temperature contrast across the pore. The emergent gas flow rate is found to vary with the pore length/radius ratio in excellent agreement with Clausing's empirical formula. The degree of collimation of the flow is quantitatively studied as a function of the length/radius ratio, and consequences for the jet force of outgassing through a dust mantle or, indeed, a rough surface are estimated. 相似文献