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1.
西藏羊八井热田地热流体成因及演化的惰性气体制约 总被引:4,自引:5,他引:4
地热流体中惰性气体的相对丰度和同位素组成,不仅可以揭露热田的热源性质,而且还能够揭示深,浅层地热流体的内在联系和演化过程等。在西藏羊八井热田的地热气体中,已检测出大量的^4He组分,3He/^4He值是大气的0.087-0.259倍,表明深部地壳物质的局部熔融为热田提供能量,浅层地热流体的3He/4He 值自西北向东南呈降低趋势,与热储温度的变化相一致,反映出侧向运移时补充了更多的壳源氦,热田北区深层地热流体具有稍高的3He/4He值,是浅层地热流体的母源,气体中氪和氙的相对丰度具有大气降水成因的特征,结合现有的实际资料,建立了热田地热流体的概念模型。 相似文献
2.
The SE Pacific stock of Patagonian grenadier (Macruronus magellanicus) showed evidence of an abrupt reduction in recruitment after 2000. This drop exceeded expectations from changes in the spawning stock biomass (SSB), indicating a change in the stock-recruitment relationship (S-R). We evaluated whether variability in recruitment could be explained by concurrent changes in three environmental indices: sea-surface temperature anomaly (SSTA); southern oscillation index (SOI); and latitudinal position of the west wind drift bifurcation (WWDL). Continuous and discrete effects of these indices were tested as covariates in linear log-log and non-linear Ricker's S-R models. Discrete effects represented regime shifts detected in SSTA (1998), SOI (1998) and WWDL (1995). While SSTA was the only continuous variable found to be significant, the discrete 1998 regime shift supported the most informative model. The best Ricker's model considered a discrete intercept change in the same year: 1998. Although a spurious correlation between SSTA and S-R changes is possible, SSTA may be reflecting major physical or biological changes relevant to M. magellanicus juveniles in the SE Pacific. 相似文献
3.
We present digitized photographs of the white-light solar corona taken during the total solar eclipse of 22–23 November, 1984, on both calibrated black-and-white film and on color film. Conditions on site in Hula, Papua New Guinea, were exceptionally clear. The color image was used to produce an isophotal map of the inner corona, from which a flattening coefficient of 0.23 was measured. The black-and-white image was enhanced through a digital radial filter. Our images are the best processed images available from the 1984 eclipse and so provide important data for synoptic observations. 相似文献
4.
Individual X-ray photons in the keV energy range produce hundreds of photoelectrons in a single pixel of a CCD array detector.
The number of photoelectrons produced is a linear function of the photon energy, allowing the measurement of spectral information
with an imaging detector system. Most solar X-ray telescopes, such as Yohkoh/SXT and Hinode/XRT, use CCD detectors in an integrating mode and are designed to make temperature estimates from multiband filter photometry.
We show how such instruments can be used in a new way to perform a limited type of this photon spectroscopy. By measuring
the variance in intensity of a series of repeated images through a single filter of an X-ray source, the mean energy per detected
photon can be determined. This energy is related to the underlying coronal spectrum, and hence it can be used to deduce the
mean plasma temperature. We apply this technique to data from the Yohkoh Soft X-Ray Telescope and compare the temperatures obtained with this technique with the temperatures derived using the standard
filter ratio method for a postflare loop system. Given the large dynamic range of the soft X-ray flux observed from the Sun,
we describe the requirements for a future instrument that would be better suited to performing photon spectroscopy.
B.J. Labonte deceased 24 October 2005. 相似文献
5.
6.
Arthur C. Reardon 《Astrophysics and Space Science》2011,336(2):369-377
Detailed analyses by independent research groups over several decades reveal a significant discrepancy between the observed
rate of periastron advance in the detached eclipsing binary star systems DI Herculis and V541 Cygni and the values theoretically
predicted from the combined classical and general relativistic effects. A modification to Newton’s gravitational theory is
proposed in this investigation to account for these discrepancies, and is represented by
F = - \fracGm1m2r3r - \fracGom1m2r2r\mathbf{F} = - \frac{Gm_{1}m_{2}}{r^{3}}\boldsymbol{r} - \frac{G_{o}m_{1}m_{2}}{r^{2}}\boldsymbol{r} 相似文献
7.
We present and interpret observations of the preflare phase of the eruptive flare of 15 November, 1991 in NOAA AR 6919. New
flux emerged in this region, indicated by arch filaments in Hα and increasing vertical flux in vector magnetograms. With increasing
frequency before the eruption, transient dark Hα fibrils were observed that crossed Hα bright plage and the magnetic inversion
line to extend from the region of flux emergence to the filament, whose eruption was associated with the flare. These crossing
fibrils were dynamic, and were often associated with sites of propagating torsional motion. These sites propagated from the
region of flux emergence into the filament flux system. We interpret these morphological and dynamic features in terms of
relaxation after magnetic reconnection episodes which create longer field lines within the filament flux system, as envisioned
in the tether cutting model, and transfer twist to it, as well.
Supplementary material to this paper is available in electronic form at http://dx.doi.org/10.1023/A:1005086108043 相似文献
8.
Frank Hill Piet Martens Keji Yoshimura Joseph Gurman Joseph Hourclé George Dimitoglou Igor Suárez-Solá Steve Wampler Kevin Reardon Alisdair Davey Richard S. Bogart Karen Q. Tian 《Earth, Moon, and Planets》2009,104(1-4):315-330
The Virtual Solar Observatory (VSO) has been developed to allow researchers, educators, and the general public to access data and images from the major sources of on-line solar data. The VSO substantially reduces the effort required to locate disparate data sets, and removes the need for the user to locate the data and learn multiple interfaces. The VSO provides a single interface to about 60 geographically distributed data sets including space- and ground-based sources. These data sets incorporate several physical variables including magnetic field, intensity, Doppler velocity, etc., and all wavelengths from X-ray to radio. All layers of the sun, from the interior to the corona, are included. In this paper we describe the system and present the interface that the user will encounter. We also discuss future enhancements planned for the system. 相似文献
9.
E.J Reardon 《Geochimica et cosmochimica acta》1983,47(11):1917-1922
The dissociation constant for SrSO04 ion pair was determined at 25°C using conductance and ion-exchange techniques. Both approaches yield values for pK of SrSO04 at zero ionic strength in the range 2.28–2.31. Previously reported values range from 2.1 to 3.0. The refinement in the dissociation constant should allow more reliable appraisals of the extent of strontium mineral solubility controls on strontium concentrations in natural water systems.The Lee and Wheaton conductance model was used to interpret the results of the conductivity measurements in strontium sulphate solutions at 25°C. Because of the limitations imposed by the solubility of celestite, a sufficiently-wide concentration range to enable determination of all three of the parameters—dissociation constant, Λ0, and the distance parameter could not be made. Instead, values are reported for the dissociation constant and Λ0 using reasonable limiting values for the distance parameter.Dowex-50 was used in the ion-exchange technique to determine the dissociation constant for SrSO04. This method was used to determine values at other temperatures as well. Although there is considerable scatter in the temperature data, a standard enthalpy for the dissociation reaction: SrSO04→ Sr2+ + SO2?4 is computed to be 8.7 ± 2 kJmole?1 at 25°C. 相似文献
10.
Kevin P. Reardon 《Solar physics》2006,239(1-2):503-517
We investigate the effects of atmospheric dispersion on observations of the Sun at the ever-higher spatial resolutions afforded
by increased apertures and improved techniques. The problems induced by atmospheric refraction are particularly significant
for solar physics because the Sun is often best observed at low elevations, and the effect of the image displacement is not
merely a loss of efficiency, but the mixing of information originating from different points on the solar surface. We calculate
the magnitude of the atmospheric dispersion for the Sun during the year and examine the problems produced by this dispersion
in both spectrographic and filter observations. We describe an observing technique for scanning spectrograph observations
that minimizes the effects of the atmospheric dispersion while maintaining a regular scanning geometry. Such an approach could
be useful for the new class of high-resolution solar spectrographs, such as SPINOR, POLIS, TRIPPEL, and ViSP.
Electronic Supplementary Material Supplementary material is available for this article at 相似文献
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