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151.
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
152.
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
153.
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
154.
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
155.
Heinz Gabler 《Ocean Dynamics》1951,4(4-6):175-181
Zusammenfassung Es wird gezeigt, wie neben dem für die Praxis wichtigen subjektiven Peilbefund durch vergleichende Messungen ein objektiver Befund mit quantitativem Gewicht erhalten werden kann. Die sich daraus ergebenden Folgerungen werden diskutiert.
On the quality of the minimum intensity in radio-goniometry
Summary In the following paper it is pointed out how it is possible to obtain, in addition to the usual subjective results which are important in practice, objective results of quantitative weight by means of comparative measurements. The consequences resulting therefrom are discussed.
Quelques remarques sur la qualité du minimum d'intensité en radiogoniométrie
Résumé On montre dans ce traité comment il est possible d'obtenir, outre les résultats usuels subjectifs qui sont d'importance dans la pratique, des résultats objectifs à poids quantitatif par des mesures comparatives, Les conséquences en résultant sont discutées.相似文献
156.
Heinz Bahr 《Aquatic Sciences - Research Across Boundaries》1953,15(2):285-301
Zusammenfassung Unter Zuhilfenahme eines festen N?hrbodens gelang die Reinkultur vonCladothrix dichotoma. Eine überführung vonCladothrix in die alsSphaerotilus natans bekannte Form gelang bei Kultivierung in einem flüssigen N?hrsubstrat nach Zusatz von Asparagin und bei h?ufiger Erneuerung
des N?hrsubstrates. Dabei war es gleichgültig, ob als Ausgangsmaterial die natürliche Standortsform vonCladothrix oder die vonSphaerotilus gew?hlt wurde. Auf festen N?hrb?den stellte sich stets typischesCladothrixwachstum ein. Ebenso l?sst sich eine auf obige Weise erhalteneSphaerotilusausbildung bei Drosselung des N?hrstoffangebotes in eineCladothrixausbildung zurückführen.
Die Frage nach der Verwandtschaft vonCladothrix undSphaerotilus kann danach dahingehend beantwortet werden, dassSphaerotilus natans als ?üppigkeitsform? vonCladothrix dichotoma aufzufassen sein dürfte. Beobachtungen anderer Autoren (zum BeispielKolkwitz, 1926, undPringsheim, 1951, 1952), würden damit eine Best?tigung erfahren. Durch die Annahme, dassSphaerotilus natans eine physiologisch bedingte Form vonCladothrix dichotoma darstellt, w?re zugleich eine Erkl?rung für die schlagartige Ausbreitung desSphaerotilus natans in Vorflutern mit Zuckerfabrikabw?ssern gegeben.
Eine Zusammenstellung aller uns erreichbaren Literatur überSphaerotilus undCladothrix wird angefügt. 相似文献
157.
Following complaints about water shortages in some areas of Gweru, the paper assessed the availability of enabling capacities to efficiently and sufficiently deliver water to the residents of Gweru in line with the existing level of demand. The key inspected capacity aspects were infrastructure, human resources, finances and physical availability of raw water at source. Purposively selected informants from Zimbabwe National Water Authority (ZINWA) and Gweru city council (GCC) provided data on the infrastructural, financial and human resources situation of GCC. Dam levels data for Gweru’s three supply dams were obtained from ZINWA records through the assistance of Sanyati Catchment Hydrologist. The raw water availability was assessed with the aid of Mann–Kendall test using a 10 years period data set from 2003 to 2012 for trend analysis. Findings revealed that the water sources were not experiencing major changes in water levels, to be precise, the changes were insignificant. However, given the increase in population and demand, any slightest negative change in the supply chain would further widen the gap between supply and demand. The study also uncovered that GCC had challenges in terms of the infrastructure, mainly due to financial constraints. Notably, GCC was not experiencing high staff turnover, but it was however, seriously under staffed and failing to effectively monitor water use in the city. Therefore, strong financial injection is required to support staff and resuscitate the reticulation system. Given the perpetual water shortages in Gweru and the status quo in the supply chain, water demand management strategies, wastewater use and consumer education are consequently proposed as measures that would ensure continuous water supply for all needs in the city. 相似文献
158.
159.
Patrice Moix Laurent Beccaletto Heinz W. Kozur Cyril Hochard Franois Rosselet Grard M. Stampfli 《Tectonophysics》2008,451(1-4):7-39
The Turkish part of the Tethyan realm is represented by a series of terranes juxtaposed through Alpine convergent movements and separated by complex suture zones. Different terranes can be defined and characterized by their dominant geological background. The Pontides domain represents a segment of the former active margin of Eurasia, where back-arc basins opened in the Triassic and separated the Sakarya terrane from neighbouring regions. Sakarya was re-accreted to Laurasia through the Balkanic mid-Cretaceous orogenic event that also affected the Rhodope and Strandja zones. The whole region from the Balkans to the Caucasus was then affected by a reversal of subduction and creation of a Late Cretaceous arc before collision with the Anatolian domain in the Eocene. If the Anatolian terrane underwent an evolution similar to Sakarya during the Late Paleozoic and Early Triassic times, both terranes had a diverging history during and after the Eo-Cimmerian collision. North of Sakarya, the Küre back-arc was closed during the Jurassic, whereas north of the Anatolian domain, the back-arc type oceans did not close before the Late Cretaceous. During the Cretaceous, both domains were affected by ophiolite obduction, but in very different ways: north directed diachronous Middle to Late Cretaceous mélange obduction on the Jurassic Sakarya passive margin; Senonian synchronous southward obduction on the Triassic passive margin of Anatolia. From this, it appears that the Izmir-Ankara suture, currently separating both terranes, is composite, and that the passive margin of Sakarya is not the conjugate margin of Anatolia. To the south, the Cimmerian Taurus domain together with the Beydağları domain (part of the larger Greater Apulian terrane), were detached from north Gondwana in the Permian during the opening of the Neotethys (East-Mediterranean basin). The drifting Cimmerian blocks entered into a soft collision with the Anatolian and related terranes in the Eo-Cimmerian orogenic phase (Late Triassic), thus suturing the Paleotethys. At that time, the Taurus plate developed foreland-type basins, filled with flysch-molasse deposits that locally overstepped the lower plate Taurus terrane and were deposited in the opening Neotethys to the south. These olistostromal deposits are characterized by pelagic Carboniferous and Permian material from the Paleotethys suture zone found in the Mersin mélange. The latter, as well as the Antalya and Mamonia domains are represented by a series of exotic units now found south of the main Taurus range. Part of the Mersin exotic material was clearly derived from the former north Anatolian passive margin (Huğlu-type series) and re-displaced during the Paleogene. This led us to propose a plate tectonic model where the Anatolian ophiolitic front is linked up with the Samail/Baër-Bassit obduction front found along the Arabian margin. The obduction front was indented by the Anatolian promontory whose eastern end was partially subducted. Continued slab roll-back of the Neotethys allowed Anatolian exotics to continue their course southwestward until their emplacement along the Taurus southern margin (Mersin) and up to the Beydağları promontory (Antaya-Mamonia) in the latest Cretaceous–Paleocene. The supra-subduction ocean opening at the back of the obduction front (Troodos-type Ocean) was finally closed by Eocene north–south shortening between Africa and Eurasia. This brought close to each other Cretaceous ophiolites derived from the north of Anatolia and those obducted on the Arabian promontory. The latter were sealed by a Maastrichtian platform, and locally never affected by Alpine tectonism, whereas those located on the eastern Anatolian plate are strongly deformed and metamorphosed, and affected by Eocene arc magmatism. These observations help to reconstruct the larger frame of the central Tethyan realm geodynamic evolution. 相似文献
160.
New brachiopods (Dimerelloidea, Rhynchonellida) from Lower Jurassic (?lower Hettangian) hemipelagic sediments of the Swiss National Park in south-eastern Engadine are described: Sulcirostra doesseggeri sp. nov. and Carapezzia engadinensis sp. nov. Sulcirostra doesseggeri is externally similar to S. fuggeri (Frauscher 1883), a dubious species, that could not be included in a comparative study, because relevant samples no longer exist. A single specimen was tentatively assigned to Sulcirostra ?zitteli (Böse 1894) by comparison of its external morphology with S. zitteli from the type locality. The partly silicified brachiopods are associated with sponge spicules, radiolarians and crinoid ossicles. Macrofossils are rare: dictyid sponges, gastropods, bivalves, crustaceans, shark teeth and scales of an actinopterygian fish. The Lower Jurassic sediments (Alpisella beds, a basal member of the Allgäu Formation) preserving the brachiopods belong to the Ortler nappe (Upper Austroalpine nappes). The exact age of the Alpisella beds is not known, as index fossils are lacking. Their stratigraphic position above the Rhaetian Kössen Formation and below the ammonite-dated Trupchun beds suggests a very Early Jurassic, probably early Hettangian age for the new brachiopod fauna. The new species of Sulcirostra and Carapezzia are confined to a very small geographic area, a peculiarity also observed in other Early Jurassic dimerelloid brachiopods. These brachiopods presumably adapted to current-dominated submarine highs, where their shells could not accumulate, except when trapped in submarine cavities or re-deposited in submarine fans. Transport by turbidity currents is suggested for the Early Jurassic dimerelloids from the Engadine. Problems with the generic definition of Sulcirostra and the higher rank classification of Carapezzia are discussed. 相似文献