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111.
Izvestiya, Atmospheric and Oceanic Physics - The 100 000-year periodicity of climate changes during the Late Pleistocene (in the last 800 ka) may be related to the respective oscillations in... 相似文献
112.
A catalog of maser spectra in the 1.35-cm water-vapor line towards the maser source NGC 2071 in a region of massive star formation
is presented for 1994–2010. The observations were carried out using the 22-m antenna of the Pushchino Radio Astronomy Observatory
with a spectral resolution of 0.101 km/s (0.0822 km/s after the end of 2005). Based on the data throughout the monitoring
since 1980, two very different cycles of maser activity were found. The first (1980–1992) is characterized by high activity
within a broad range of radial velocities. Emission at velocities near 7 km/s predominated in 1980–1986, and emission near
14–16 km/s, in 1987–1992. In 1997–2008, the maser intensity was appreciably lower than in the first activity cycle. Numerous
flares of individual emission features were observed. Identifications based on VLA data show that strong flares took place
in both maser sources, IRS1 and IRS3. Both sources demonstrated a low level of maser activity during essentially the same
epochs (1977, 1995–1997, and the close of 2009 through the beginning of 2010), although the sources are separated by at least
2000 AU. 相似文献
113.
114.
Kuninao Tada Marut Suksomjit Kazuhiko Ichimi Yui Funaki Shigeru Montani Machiko Yamada Paul J. Harrison 《Journal of Oceanography》2009,65(6):885-891
The importance of the nitrogen source for phytoplankton growth in a highly eutrophic embayment, Dokai Bay, was investigated.
The DIN concentration often exceeded 100 μM of which 40–70% was NH4
+. During two incubation experiments, the natural assemblage of mainly diatoms took up NH4
+ instead of NO3
−. The growth of two Skeletonema species isolated in Dokai Bay were significantly faster on NH4
+ (1.86 and 1.27 div. d−1 respectively) than on NO3
− (1.55 and 1.04 div. d−1 respectively). Our results indicated that these diatoms could grow faster by using NH4
+ compared to NO3
− in this eutrophic bay. 相似文献
115.
G. L. Gdalevich A. Kh. Depueva N. I. Izhovkina V. D. Ozerov 《Geomagnetism and Aeronomy》2010,50(1):69-78
The results of the Cosmos-900 satellite observ ations of plasma density inhomogeneities in the geomagnetic equator region
and the longitudinal distributions of the equatorial spread-F, according to the Intercosmos-19 satellite data are presented. It is show n that the dependence of radiosignal propagation
in the ionosphere on geophysical parameters is related to development of the electrostatic instability of the inhomo-geneous
ionospheric plasma. The longitudinal dependence of the spread-F, can reflect the influence of the energetic sources, located outside the ionospheric layer that scatters a radio pulse, on
the ionosphere. The manifestation of the longitudinal effect in the equatorial spread-F, in the Atlantic region can be explained by the influence of the cone instability on the plasma electrodynamics in the South
Atlantic geomagnetic anomaly. 相似文献
116.
117.
We present here a numerical modelling study of dislocations in perovskite CaTiO3. The dislocation core structures and properties are calculated through the Peierls–Nabarro model using the generalized stacking
fault (GSF) results as a starting model. The GSF are determined from first-principles calculations using the VASP code. The
dislocation properties such as collinear, planar core spreading and Peierls stresses are determined for the following slip
systems: [100](010), [100](001), [010](100), [010](001), [001](100), [001](010),
and All dislocations exhibit lattice friction, but glide appears to be easier for [100](010) and [010](100).
[001](010) and [001](100) exhibit collinear dissociation. Comparing Peierls stresses among tausonite (SrTiO3), perovskite (CaTiO3) and MgSiO3 perovskite demonstrates the strong influence of orthorhombic distortions on lattice friction. However, and despite some quantitative
differences, CaTiO3 appears to be a satisfactory analogue material for MgSiO3 perovskite as far as dislocation glide is concerned. 相似文献
118.
Anna Kwietniak 《Acta Geophysica》2015,63(1):201-213
Long Period Long Duration (LPLD) signals are unusual seismic events that can be observed during hydraulic fracturing. These events are very similar in appearance to tectonic tremors sequences, which were first observed in subduction zones. Their nature is not well known. LPLD might be related to the productivity of the reservoir. Different methods of the LPLD events’ detection recorded during hydraulic fracturing are presented. The author applied two methods for LPLD detection–Butterworth filtering and Continuous Wavelet Transform (CWT). Additionally, a new approach to LPLD events detection–instantaneous seismic attributes–was used, common in a classical seismic interpretation but not in microseismic monitoring. 相似文献
119.
Several horizons of a unique lithotype called “chertbreccia” are interbedded within the Proterozoic platform sediments of
the Peninsular India. These cherty rocks with brecciated texture appearing as blocky masses were earlier diversely interpreted
as being products of disparate processes such as fault-zone breccias, collapse breccias, and so on. Two of these horizons,
one from the Kaladgi Basin (Dharwar Craton) and the other from the Dhar Forest Inlier of the Vindhyanchal Basin (Bundelkhand
— Aravalli Craton) are compared in context of their geological setting, field relations and petrological constitution. A model
of the mode of development of these peculiar rocks is reconstructed, taking into account their characters and limitations
of previous interpretations. They are interpreted as transported debris deposits of syntectonogenic material released during
the episodic activity of the growth faults of the Kaladgi and Vindhyanchal Basins that was diagenetically silicified. 相似文献
120.
A robust satellite data analysis technique (RAT) has been recently proposed as a suitable tool for satellite TIR surveys in seismically active regions and already successfully tested in different cases of earthquakes (both high and medium–low magnitudes).In this paper, the efficiency and the potentialities of the RAT technique have been tested even when it is applied to a wide area with extremely variable topography, land coverage and climatic characteristics (the whole Indian subcontinent). Bhuj–Gujarat's earthquake (occurred on 26th January 2001, MS 7.9) has been considered as a test case in the validation phase, while a relatively unperturbed period (no earthquakes with MS ≥ 5, in the same region and in the same period) has been analyzed for confutation purposes. To this aim, 6 years of Meteosat-5 TIR observations have been processed for the characterization of the TIR signal behaviour at each specific observation time and location.The anomalous TIR values, detected by RAT, have been evaluated in terms of time–space persistence in order to establish the existence of actually significant anomalous transients. The results indicate that the studied area was affected by significant positive thermal anomalies which were identified, at different intensity levels, not far from the Gujarat coast (since 15th January, but with a clearer evidence on 22nd January) and near the epicentral area (mainly on 21st January). On 25th January (1 day before Gujarat's earthquake) significant TIR anomalies appear on the Northern Indian subcontinent, showing a remarkable coincidence with the principal tectonic lineaments of the region (thrust Himalayan boundary).On the other hand, the results of the confutation analysis indicate that no meaningful TIR anomalies appear in the absence of seismic events with MS ≥ 5. 相似文献