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141.
142.
143.
A detailed compilation of the most recent values of the solar constant is given (13 values published from 1967 to 1970). The most probable value seems to be 1.95 cal cm–2 min–1 or 1.36 kW m–2 with a formal rms error of ± 0.3%. The corresponding effective temperature is 5770K.Systematic errors of the order of ± 1%, but also a possible variability of the same order cannot be excluded. 相似文献
144.
The compressibility of -Mns (alabandite) was determined by x-ray analysis using a Mao-Bell type diamond anvil cell. The zero pressure bulk modulus (K0) is 74±2 GPa with the pressure derivative of the bulk modulus (Ko) fixed at four. Allowing (Ko) to vary yielded a statistically better fit with K0 = 88±6 GPa and k0 = 2.2±0.6. Our data combined with the data of McCammon (1991) gave Ko = 73±1 GPa with ko fixed at four. A fit with ko allowed to vary yielded ko = 75±2 GPa and ko = 3.7±0.4. Alabandite transformed from the B1 structure (NaCl-type) to an unknown high-pressure phase at 26 GPa. The high-pressure phase has lower than hexagonal symmetry and it is stable to at least 46±4 GPa.Also affiliated with the James Franck Institute, University of Chicago 相似文献
145.
Heinz Neckel 《Solar physics》1996,167(1-2):9-23
The limb-darkening data published by Neckel and Labs (1994) (5th-order polynomials P
5(), = cos ) are used to represent the limb darkening by the functions L
n(), proposed first by Kourganoff (1949a). When plotted against wavelength, the coefficients of these functions show a rather low scatter and appear to be linear functions of either
–1 or
#x2212;5. 相似文献
146.
The conversion of our centre of disk intensities published in 1968/70 into mean disk intensities has been repeated, using more accurate data for the centre-to-limb variation of both continuous radiation and strong absorption lines.The random observational mean error of the new irradiance data very likely is not larger than 1.5% in the UV and not larger than 1% in the visible and infrared. Comparison with the fluxes of Sun-like stars observed by Hardorp (1980) confirms these errors and seems to exclude the possibility of a systematic, wavelength-dependent scale error which would correspond to a temperature difference larger than 50 K.The resulting integral value of the irradiance between 0.33 and 1.25 is 1.060, the corresponding value of the solar constant lies between 1.368 and 1.377 kWm-2.Proceedings of the 14th ESLAB Symposium on Physics of Solar Variations, 16–19 September 1980, Scheveningen, The Netherlands. 相似文献
147.
Wavelengths and bisector indices (a special measure for the asymmetry of a line near its bottom) are determined for 70 lines in each of 47 high-dispersion spectra. The spectra were obtained with the Fourier Transform Spectrograph connected to the McMath Telescope at Kitt Peak National Observatory; they all cover the same spectral range from 3200 to 4000 Å and concern either the full disk (19 disk spectra), or the disk center (9 center spectra), or two areas at sin = 0.85 on the west- and east-side of the disk (19 limb spectra). The main observing seasons were June 1986, June 1987, April and June/July 1988. The - relative - position of an individual line in one spectrum can be established with a precision of about 4 m s-1, the precision of one bisector index is 1–2 m s-1.Wavelengths and bisector indices show of course the typical characteristics which result from the familiar effects known as blueshift, limb effect and line asymmetry. However, concerning their variations in time, unexpected results are obtained:(1) Even in disk spectra the time-scales of the wavelength variations are often in the order of one hour or less. (2) For all 3 types of spectra (disk, center, limb) the variations depend not only on the known parameters such as line depth and - occasionally - excitation potential, but also - often even primarily - on wavelength. (3) In center spectra, the wavelength differences between strong and faint lines can vary by as much as 500 m s-1, in disk spectra short-time variations of wavelength differences can amount to more than 50 m s-1. (4) For most spectra there is not only a very pronounced and narrow correlation between line shift and line temperature (a special measure for the line depth), but also a significant correlation between line shift and variation of the bisector index.Clearly, the observed effects must be attributed to variations of the velocity fields in the upper photosphere/lower chromosphere (super-granulation cells, overshooting, oscillations), which either influence the line wavelengths directly via the Doppler-effect, or indirectly by changing the contrast between the blue-shifted granules and the red-shifted intergranular lanes. Because of the snapshot character of the observations, no reliable conclusions can be drawn on the actual time-dependency. 相似文献
148.
The suspicion of Elste (1990), that telescopic stray light together with imperfect collimation of telescope and spectrograph could be a possible explanation for the systematic differences and variations found by Neckel and Labs (1987) in many limb-darkening scans, proves to be unfounded for the following reasons: (1)The collimation was performed very precisely; (2) the telescope mirrors remained fixed in position and direction during most of the observing period; (3) stray light effects depending on hour angle were not detectable; (4) in the same collimation status, also many almost symmetric scans had been recorded; (5) the observed east-west differences in the solar intensities are partly even larger than the total amount of stray light (from telescope and sky!) observed as sky-background just outside the limb; (6) any east-west differences in the sky-background near the limb are just a few 0.01% of the disk center intensity; (7) the differences of the average intensities along eastern and western radius appear to be correlated with the east-west differences of the intensity's R.M.S. 相似文献
149.
Gabriele M. Berberich Tobias Sattler Dietrich Klimetzek Simon A. Benk Martin B. Berberich Daniela Polag Heinz Friedrich Schöler Elliot Atlas 《Journal of Atmospheric Chemistry》2017,74(2):261-281
We investigated and evaluated the occurrence of fault zone tracer gases (CO2, He, Rn), volatile organohalogens (CH3Cl, CHCl3, CHBr3), alkanes and limonene in soil and nest gases of red wood ants (RWA) in comparison to ambient air, in a seismically active area. In this new approach, we compared RWA-free areas to RWA-areas by combining different investigation and analytical methods. In soil gas, the fault zone tracer gas Rn was surprisingly highly correlated to limonene, suggesting a combination of biotic production of limonene and abiotic degassing of Rn in a seismically active area; moderate correlations were found with trihalomethanes and other halocarbons. In RWA nests a variety of elevated concentrations of haloforms were found, while remaining below the atmospheric background values in RWA-free areas. The evidence of CHCl3 in RWA nests is the first record. Its average concentrations in nests of F. rufa and F. polyctena were up to 3 fold higher than atmospheric background and up to 28–70 fold higher compared to e.g. volcanic emissions being considered as one of its main geogenic sources. Thus, RWA nests could possibly be an additional source for CHCl3 liberation. Consequently, apart from RWA being bioindicators for seismically active degassing faults, they might also be used as bioindicators for CHCl3 formation in forest soils. Although we cannot yet differentiate between a geogenic/abiotic and a biotic formation. RWA nests will have to be reconsidered for halocarbon formation in future quantifications of geochemical cycles at global scale, since they impact organic soil chemistry through biotic and/or abiotic pathways. Therefore, further larger-scale research in different tectonic settings but also in well-known CHCl3 “hot spot” study areas such as the Klosterhede area (Denmark) should focus directly on gas sampling from confirmed active fault systems. Nests of other ant species should be addressed to compare seasonal, diurnal and nocturnal variations of degassing procedures in relation to earth tides, different geologic settings, and tectonic events such as earthquakes and on quantifying the fluxes to the atmosphere. 相似文献
150.
Dr. Heinz Meixner 《Contributions to Mineralogy and Petrology》1950,2(3):195-209
Zusammenfassung Bei den hier beschriebenen Mineralfunden handelt es sich teils um Neubearbeitungen alter Stücke aus Museums- oder Privatsammlungen, teils um neue Aufsammlungen.Cölestin von Kreuth bei Bleiberg.Slavikit undFibroferrit bei Rennweg.Pyrargyrit von Ruden bei Völkermarkt. Ein auffallend schönerZinnoberkristall vom steir. Erzberg.- und-Schwefel aus dem Köflach-Voitsberger Braunkohlengebiet. NetteRealgarkristalle vom Mischlinggraben im Lavanttal.Lansfordit undNesquehonit aus dem Serpentingebiet von Kraubat.Valentinit- undArsenolitkristalle, Symplesit undFerrisymplesit vom Hüttenberger Erzberg (Österreichs mineralartenreichster Lagerstätte). Insgesamt eine kleine Auswahl mineralogischer Neuentdeckungen (1947/49) aus dem Ostalpenraum, die zeigen, daß die mineralogische Durchforschung auch hier noch lange nicht abgeschlossen ist. Weitere Mitteilungen sollen folgen. 相似文献