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61.
Dr. R. Siksna 《Pure and Applied Geophysics》1955,31(1):9-20
Zusammenfassung Konstruktionseinzelheiten eines photoelektrischen Kernzählers werden beschrieben. Die Bedienung des Zählers ist elektrifiziert und erfolgt durch elektromagnetische Ventile. Besondere Befeuchter werden benutzt. Ein Ansatz für visuelle Beobachtung der Nebelbildungserscheinungen in dem Absorptionsrohr ist eingeführt. Für Aussiebung der geladenen Kerne ist ein Kondensator angebaut, der in einfacher Weise in einen Grossionenzähler umgewandelt werden kann. Mit einer Kamera als Zusatzteil kann der Zähler in einen kombinierten photoelektrischen und photographischen Kondensationskernzähler umgewandelt werden.
Summary Details of the construction of a photo-electric nucleus counter are described. The operation of the counter is electrified and is carried out by electromagnetic valves. Special humidifiers are used. Visual observation of the fog formation phenomena in the absorption tube is introduced. A condenser for sifting the charged nuclei is built in, which in a simple way can be converted into a counter for large ions. As an accessory a camera is provided so that the counter can be used as a combined photo-electric and photographic condensation nuclei counter.相似文献
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Dr. M. Treuil J. Varet M. Billhot F. Barberi 《Contributions to Mineralogy and Petrology》1971,30(1):84-94
NI, Cu and Zn were measured polarographically in 34 samples of volcanic rocks from the chain of Erta'Ale, Ethiopia. In this chain all rock types from picritic basalts to alkaline and peralkaline rhyolites can be found. The series is marked by a considerable iron enrichment in the intermediate stages. The distribution of Ni, Cu and Zn in the series emphasizes the efficiency of the crystal-field theory in accounting for the behaviour of the elements during magmatic fractionation. Nickel shows a regular variation throughout the trend. The variation of copper is similar to that of iron, but the relative rates of enrichment and depletion show that they are not necessarily associated with the same mineral phases. The behaviour of Zn is rather irregular. 相似文献
65.
Dr. Djuro Radinović 《Meteorology and Atmospheric Physics》1965,14(3):279-299
Summary Changes occurring in the thermal structure of air masses in the Alps area and the West Mediterranean region, during cyclonic developments in the Gulf of Genoa, have been considered. The effect of the height and the form of the mountain ranges as well as that of the nonadiabatic processes, on the deformation of the thickness pattern, have been discussed. These factors have been further taken into consideration for a modification of the equations used inEstoque's method for the baroclinic model, and a new method has been developed for forecasting cyclogenesis in regions bounded by mountain ranges.
With 5 Figures 相似文献
Zusasmmenfassung Es werden die Änderungen der thermischen Struktur der Luftmassen im Alpengebiet und im westlichen Mittelmeerraum bei der Entwicklung von Zyklonen im Golf von Genua aufgezeigt und die Einflüsse von Höhe und Form der Gebirgszüge sowie von nichtadiabatischen Vorgängen auf die Deformation der relativen Topographie besprochen. Diese Faktoren werden auch zur Modifikation der in der Methode vonEstoque für ein baroklines Modell verwendeten Gleichungen in Betracht gezogen und damit wird eine neue Methode zur Vorhersage der Zyklogenese unter dem Einfluß von Gebirgszügen entwickelt.
Résumé On expose dans ce mémoire à quelles modifications la structure thermique des masses d'air est soumise dans la région des Alpes et dans le bassin occidental de la Méditerranée lors du développement de dépressions sur le Golfe de Gênes. On y discute en outre l'influence de la hauteur et de la forme des chaînes de montagnes ainsi que celle des processus non-adiabatiques sur des déformations de la topographie relative. Tous ces éléments sont pris en considération pour leur adapter les équations utilisées dans le modèle baroclined'Estoque. Par là, on accède à une nouvelle méthode de prévision de la cyclogénèse, méthode qui tient compte de l'influence des chaînes de montagnes.
With 5 Figures 相似文献
66.
Dr. R. R. Thaman 《GeoJournal》1988,16(2):211-227
Although modernization has undoubtedly brought about significant improvements in and access to modern health services and
has lowered the previously high incidence of some infectious diseases and perinatal deaths, there is increasingly widespread
evidence that some old and some new, often very serious health and nutritional problems still exist in all parts of the often
“Edenized” Pacific islands. Although “development” has occurred, both infectious and non-communicable degenerative diseases,
perinatal mortality, and nuclear pollution still constitute major health problems, and food systems, nutritional status, and
nutrition-linked health seem to have deteriorated. 相似文献
67.
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Brian Stewart Hoyle Dr. 《GeoJournal》1986,12(3):233-242
The significant role of transport in the development of less-developed countries is widely accepted, but the critical importance of seaports is often under-appreciated. Evidence from the Indian Ocean ports of Kenya and Tanzania is used in this paper to illustrate and support the argument that efficient port operation is an essential contributory factor in the development process. 相似文献
69.
Assoc. Prof. Dr. X. -Q. Yang Dr. Q. Xie Prof. Y. -Q. Ni Dr. S. -S. Huang 《Meteorology and Atmospheric Physics》1996,61(3-4):153-186
Summary A coupled ocean-atmosphere anomaly model has been developed for simulating ENSO cycle and its mechanism-study in this paper. After a long model run, the coupled model is successful in demonstrating ENSO-like irregular interannual variability and corresponding horizontal spatial structures. Based on the simulated results, the dynamics and the thermodynamics of the model ENSO cycle have been investigated, and in particular the negative feedback mechanisms that act to oppose instability of air-sea interaction, inducing termination of warm and cold events, have been examined. A detailed analysis of the oceanic wave dynamical properties and heat budget of the SST changes in a representative cycle suggest that the negative feedback mechanism to check the unstable growth of a warm event obviously differs from that of a cold event. The mechanism that induces decay and termination of a cold event is closely related to the negative, delayed feedback effect produced by the oceanic dynamical wave reflection at the western boundary. However, independent of the wave reflection effect, the negative feedback mechanism by which the coupled system returns from a warm event is associated with a slowly eastward-propagating coupling mode. Accompanied with the strong unstable development of the equatorial positive SST anomaly, the anomalous upwelling of cold water generated off the equator and the nonlinear anomalous meridional advection generated in the equator west of instability area jointly restrain the instability and finally plunge the system from a mature warm phase into a weak cold phase. A comparison between the results from the present model and the previous works is also discussed in this paper.With 16 Figures 相似文献
70.