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531.
We have speculated on the influence of organic material on extinction and absorption coefficients and liquid water content of fogs and of clouds immediately after their condensational stage. It results therefore, that the reduction of the speed of growth from fog to cloud droplets due to the presence of organic films largely reduces the properties mentioned. Compared to that their increase coming from the surface tension reduction due to organic material being dissolved or building up films is expected to be less effective. 相似文献
532.
Ing. Kurt Chalupa 《Theoretical and Applied Climatology》1968,16(4):434-441
Zusammenfassung Es wird über die Ergebnisse der SO2-Immissionsregistrierungen an der Zentralanstalt für Meteorologie und Geodynamik in Wien-Hohe Warte im Winter 1967/68 berichtet. Die Tages- und Monatsmittelwerte sowie die Immissionskenngrößen werden mitgeteilt. Ferner wird die Abhängigkeit der gemessenen SO2-Werte von Windrichtung und Windstärke untersucht.
Mit 2 Abbildungen 相似文献
Summary The author gives a report on the results of the SO2 immission recordings which have been effectuated at the Zentralanstalt für Meteorologic und Geodynamik in Vienna (Hohe Warte) during the winter 1967 to 1968. Daily and monthly means are given as well as the immission parametersI 1 andI 2. Further, the dependancy of the measured amounts of SO2 from wind direction and wind speed is discussed.
Résumé On rapporte ici sur les résultats des enregistrements d'immissions de SO2 effectués durant l'hiver 1967–1968 à l'Institut central de Météorologie et de Géodynamique à Vienne (Autriche). On communique les moyennes journalières et mensuelles ainsi que les dimensions des immissions. On recherche enfin les relations pouvant exister entre les valeurs mesurées de SO2 d'une part, les directions et forces du vent d'autre part.
Mit 2 Abbildungen 相似文献
533.
Dr. Kurt Lemcke 《International Journal of Earth Sciences》1967,56(1):262-266
Zusammenfassung Die Reinheit der vom Moldanubikum stammenden subalpinen Glassande wird nur verständlich, wenn man fluviatilen Transport bis in unmittelbare Nähe ihres Ablagerungsraumes annimmt. Er erfolgte vermutlich über ein Festland, das sich im höheren Chatt in Ostbayern zwischen der Sedimentation der Chattsande und der der Hangenden Chattmergel herausbildete.
The Glassande (vitreous sands) in the Subalpine Molasse derived from the Bayrischer Wald (in the NE) without any contamination by Molasse material. This required fluviatile transportation immediately to the site of deposition, which was made possible by temporary regression in upper chattian time.
Résumé Les Glassande (sables vitrieux) dans la molasse subalpine provenaient du Bayrischer Wald (NE) sans aucune impureté par matériel molassique. Cela rendait nécessaire le transport fluviatile jusqu'au point de dépôt, qui était possible à cause d'une régression temporaire en Chattien Supérieur.
Glassande . , , .相似文献
534.
One large (8.5 mm) chondrule in the Bali carbonaceous chondrite is strongly enriched in refractory elements similarily to the white objects in Allende which are widely believed to be “primitive” condensates. However, detailed investigations show the Bali chondrule to have an element distribution opposite to that predicted by the “primitive condensation” models. Refractory elements like Ti and Al are enriched at or near the surface of the chondrule. The contents of some volatile elements, e.g. Na, Si, and Cr, are higher in the central portion. It is suggested that this chondrule - and similar objects in other C-chondrites - originated in one, or more likely several, impact events and that the element distribution is the result of volatilization-condensation. 相似文献
535.
Warren L. Prell William H. Hutson Douglas F. Williams Allan W. H. B Kurt Geitzenauer Barbara Molfino 《Quaternary Research》1980,14(3):309-336
A seasonal reconstruction of the Indian Ocean during the last glacial maximum (18,000 yr B.P.) reveals that its surface circulation and sea surface temperature patterns were significantly different from the modern Indian Ocean. This reconstruction is based on the planktonic foraminiferal biogeography and estimated sea surface temperatures in 42 Indian Ocean samples. Compared to modern conditions, the polar front was 5° to 10° latitude further north during the last glacial maximum; the Subtropical Convergence was 2° to 5° latitude further north. The West Australian Current was more intense as part of the West Wind Drift was deflected northward along the coast of Australia. The Agulhas Current was cooler and weaker during the summer and more saline and subtropical during the winter. In general, the low latitudes underwent little temperature change. The western Arabian Sea was warmer which implies less upwelling and a weaker Southwest Monsoon. On the average, the Indian Ocean was 1.9°C cooler in February and 1.7°C cooler in August during the last glacial maximum. 相似文献
536.
537.
Kurt Kalle 《Ocean Dynamics》1957,10(3):99-108
Zusammenfassung Im folgenden wird eine neuartige Aräometer-Apparatur zur Dichte- und Salzgehaltsbestimmung von Meerwasserproben beschrieben. Vor ähnlichen Apparaten zeichnet sie sich durch folgende Punkte aus:Sie ist besonders klein und kompakt gebaut und benötigt mit Vorspülen nur 60 bis 80 ccm Meerwasser. — Der Aräometer-Schwimmer selbst hat ein Volumen von nur 7 ccm. Dadurch, daß er an einem Härchen aufgehängt und die Oberflächenspannung durch Zugabe einiger Tropfen einer Detergenz-Lösung aufgehoben ist, wird ein reibungsloses Gleiten des Schwimmers ermöglicht. — Infolgedessen läßt sich der Auftrieb mit der großen Genauigkeit von 0,05 mg messen, was einer Empfindlichkeit von 0,01 S entspricht. — Als Meßinstrument dient eine kompakt gebaute Tor-sionswaage mit kreisförmiger Ableseskala, die sich in bequemer Höhe zum Auge befindet. Der Gesamtwägebereich umfaßt 200 mg, so daß der gesamte ozeanische Meßbereich von 0 bis 40 S ohne Schwimmerwechsel erfaßbar ist. — Gegenüber der Titration des Cl-Gehaltes hat die Methode den Vorteil, daß bei etwas erhöhter Empfindlichkeit und Arbeitsgeschwindigkeit im Serienbetrieb die Ablesung des Zeigers und des Thermometers wesentlich weniger ermüdend ist als die diffizile tropfenweise Zugabe der Silbernitratlösung und die Beobachtung des Indikatorumschlagpunktes. — Die Endberechnung des Salzgehaltes erfolgt über die beiden beobachteten Werte von Gewicht (an der Torsionswaage) und Temperatur (am Thermometer) und mit Hilfe einer bequem ablesbaren Fluchtentafel. — Der Meßvorgang selbst erfordert weder Chemikalien noch den Anschluß von Wasser oder elektrischem Strom.
A simple small-type areometer for the precise determination of salinity and density in seawater
Summary The present paper describes a newly developed areometer for the determination of salinity and density of sea-water. The apparatus is distinguished by the following features:The areometer is extremely small, its construction is very compact; including preliminary rinsing, it requires only 60 to 80 cm3 of sea-water. The volume of the areometer float itself is 7 cm3 only. Besides, by suspending the float by a fine hair and suppressing surface tension by adding a few drops of detergent solution the float is enabled to slide without friction. Owing to these two operations, the weight can be determined with so high an accuracy as 0,05 mg, corresponding to a sensitivity of 0,01 S. — A compact torsion-balance which, at a convenient height, includes a circular reading scale, serves as a measuring instrument. The total weighing range of the balance amounts to 200 mg, thus enabling the entire oceanic measuring range from 0 to 40 S to be determined without having to change the float. — In comparison with chlorinity titration the new method offers the advantage of an increased sensitivity and a higher working speed, since in serial investigations reading of the indicator needle and of the thermometer is far less tiring than the troublesome addition of silver nitrate solution and the simultaneous observation of the equivalance point. — The definitive determination of salinity is carried out with the aid of the two observed values of weight (on the torsion balance) and temperature (on the thermometer) and a conveniently readable nomograph. — The measuring procedure requires neither the use of chemicals, nor water connection, nor power equipment.Résumé Le travail actuel décrit un nouvel aréomètre pour déterminer la salinité et la densité des échantillons d'eau de mer. Cet appareil est caractérisé par sa petitesse, par sa construction compacte, par la quantité insignifiante d'eau de mer de 60 à 80 cm3 qu'il demande, y compris l'eau pour le rincement préalable, et par le petit volume de seulement 7 cm3 de son flotteur. De plus, en suspendant le flotteur par un cheveu fin et en supprimant la tension superficielle de liquide par l'addition de plusieurs gouttes d'une solution de détersion on réussit à faire glisser sans friction le flotteur. Ces deux opérations permettent de mesurer le poids à l'extrême précision de 0,05 mg près, ce qui est identique à la sensibilité de 0,01 S. — Pour des mesures on se sert d'une balance compacte à torsion munie d'une échelle circulaire à lecture. Cette échelle se trouve installée à une hauteur convenable aux yeux. L'étendue totale de la balance va jusqu'à 200 mg, ce qui permet d'étudier l'entière étendue de mesure océanique de 0 à 40 S sans changer de flotteur. — Confrontant la méthode de titrage du chlore avec la nouvelle méthode, on remarquera que la lecture de l'aiguille et du thermomètre est beaucoup moins fatigante que la pénible addition par gouttes du nitrate d'argent et l'observation simultanée du moment de l'équilibre, surtout dans le cas où les circonstances demandent l'observation d'une sensibilité un peu élevée ou une plus grande rapidité de travail lors des recherches en série. — Le calcul définitif de la salinité se fait à l'aide de deux valeurs observées, à savoir le poids (sur la balance à torsion) et la température (sur le thermomètre), et au moyen d'un nomogramme bien lisible. — La méthode de mesure elle-même ne demande ni emploi de substances chimiques, ni distribution d'eau, ni installation d'énergie.
Un aréomètre de simple construction pour la précise détermination de la salinité et de la densité de l'eau de mer相似文献
538.
Kurt A. Haberyan 《Journal of Paleolimnology》1990,3(1):35-44
Sediment trap collections near Cape Maclear, Lake Malai, were compared to phytoplankton and surface sediment diatoms to assess taphonomic variations. The sedimenting diatom community became progressively different from the diatom plankton with increasing depth: long Nitzschia species were strongly under-represented in the traps (annually, 53% among planktonic diatoms vs. 14% in the offshore 29 m trap; p0.005 by Kruskal-Wallis test), while Melosira was greatly over-represented in traps (32% vs. 57%; p<0.005). The abundances of the minor taxa (Rhopalodia, Fragilaria, Cymbella, and Surirella) were greatly enhanced in traps relative to the plankton, but they were still relatively uncommon (<3% of all diatoms each). Differences in grazing, dissolution, and sinking rates alone are insufficient to account for these distortions; a combination of these, plus perhaps unknown factors, strongly influence the deposited assemblage.These misrepresentations were also present at the sediment surface. The greatest discrepancy was noted for Melosira (32% of plankton vs. 53% of sediment surface diatoms; p<0.005) and for elongate Nitzschia species (53% of plankton vs. 0.8% in sediments; p<0.005). In Lake Malai, at least, paleolimnologists must not assume a straightforward correlation of modern and fossil assemblages. 相似文献
539.
Kurt F. Kipfmueller 《Quaternary Research》2008,70(2):173-187
Ring widths from whitebark pine (Pinus albicaulis Englem.) and subalpine larch (Larix lyallii Parl.) collected at three high-elevation sites were used to develop tree-growth chronologies to reconstruct summer temperature anomalies. A step-wise multiple regression procedure was used to screen potential predictor variables to generate a transfer function capable of skillfully reconstructing summer temperature. The resulting regression model explained approximately 38% of the adjusted variance in the instrumental temperature record. The fidelity of the reconstruction was verified using product mean and sign tests, both of which suggested significant predictive power in the reconstructions (p < 0.05). Reduction of error (RE) and coefficient of efficiency (CE) measures were both positive, indicating the reconstruction contained useful climate information. Cool periods often coincided with reduced solar activity and/or periods of increased volcanic activity. Differences between this reconstruction and others encompassing a broader geographic scale highlight the importance of developing local reconstructions of climate variability, particularly when used in conjunction with ecological data sets that describe the occurrence of fires or insect epidemics. Mixed and divergent climate-response relationships were evident in the whitebark pine chronologies and suggest subalpine larch may be a more useful species than whitebark pine to target for the development of temperature reconstructions in this region. 相似文献
540.
Recent field work in Lower Cretaceous successions of the Agadir-Essaouira region, western High Atlas, Morocco, have resulted in 489 belemnite guards collected bed-by-bed from the lower Valanginian – upper Hauterivian interval. These findings are described and discussed in their biostratigraphic, taxonomic, palaeoecologic and palaeobiogeographic context. The most common belemnite genera, Hibolithes, Vaunagites?, and Duvalia, are of Meditteranean affinities and closely related to Spanish, French, and Bulgarian faunas. Less common taxa include Pseudoduvalia and Berriasibelus. The genus Pseudobelus, however, common in southeastern France and southern Spain, is rare in the Moroccan sections. The palaeoecological interpretation of these observations result in the recognition of three belemnite assemblages, characterizing different marine settings: 1) A Hibolithes - Duvalia assemblage which is typical for inner to middle shelf settings. These are relatively shallow marine environments with a high input of siliciclastics. 2) A Duvalia - Hibolithes assemblage of the outer shelf setting. Duvalia spp. is the most common genus, Hibolithes spp. is less common, while Berriasibelus spp. and Pseudobelus spp. are rare. 3) A Duvalia - Pseudobelus assemblage of hemi-pelagic preference. Duvalia is most common, next is Pseudobelus. 相似文献