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181.
182.
183.
Josef Kabeláč 《Studia Geophysica et Geodaetica》1970,14(3):336-339
Zusammenfassung Es wird eine neue Bedingung, Gl. (6), angeführt, die von den bereits ausgeglichenen, z. B. durch den Stundenwinkel t und die
Deklination δ definierten Richtungen der Seiten des Raumnetzes erfüllt werden muss. Zur Demonstration dieser Bedingung wird
ein Modell des Raumnetzes in der Form eines Tetraeders benutzt (Abb. 1).
Address: Karlovo nám. 13, Praha 2. 相似文献
Address: Karlovo nám. 13, Praha 2. 相似文献
184.
Milan Rieder Miroslav Huka Dagmar Kučerová Luděk Minařík Jiří Obermajer Pavel Povondra 《Contributions to Mineralogy and Petrology》1970,27(2):131-158
Compositions of natural lithium-iron micas are approximated best by the sidero-phyllite-polylithionite join. These micas contain little or no magnesium and manganese. Their octahedral sheets contain close to two trivalent cations (mainly aluminum) in small crystallographic sites and a variable quantity of lithium and R+2 (mainly iron) in large sites. Octahedral vacancies are situated mostly in large sites. Lithium and R+2 approach a 44 replacement relationship in micas with octahedral occupancy close to six. Lithium and fluorine show a good positive correlation (small excess of fluorine over lithium), which indicates a crystallochemical association between them. There is a less distinct positive correlation between lithium and R+4.Based on simplifications, a calculation shows that about two-thirds of octahedral vacancies are caused by substitutions within the octahedral sheet, one-third, by tetrahedral substitutions. Different methods of calculating the crystallochemical formula yield slightly different numbers of octahedral vacancies, but do not affect the mica's position in plots of physical parameters against composition. If a crystallochemical formula is calculated from analysis of a mica contaminated with quartz, topaz, or feldspar, the apparent number of octahedral vacancies increases; such a formula exhibits unusual behavior in composition plots. 相似文献
185.
Summary The core waves recorded at four seismograph stations in Central Europe were investigated with the aim to find the most suitable set of travel-time curves and a fitting model of the core structure. Another travel-time curve was constructed by means of time differences between the core phases. The differences in the features of the travel-time curves were studied using records of shallow, intermediate and deep shocks from the same focal region (Tonga). 相似文献
186.
Vladimír Kropáček Miroslav Krs Reviewer F. Janák 《Studia Geophysica et Geodaetica》1971,15(2):161-172
Summary The paper deals with the magnetic properties of the natural minerals haematite, ilmenite and pyrrhotite. The natural remanent magnetization Jn, the volume susceptibility , the specific magnetization of saturation so, the Curie temperature , the A.C. demagnetization of natural remanent magnetization, the thermal demagnetization Jn, the temperature dependence of the specific magnetization of saturation, and several other parameters were determined for the individual sets of minerals. Since natural minerals can and do contain various heterogeneous and isomorphic admixtures, their magnetic properties may change depending on the content and type of these admixtures. Therefore, all the investigations of the magnetic properties described in this paper were carried out with extensive sets of minerals, representing various Czechoslovak and world localities. A number of interesting results were obtained from the executed experiments, e.g., the different stability of the natural remanent magnetization of haematite with respect to A.C. demagnetization, the presence and type of heterogeneous inclusions in ilmenite, the phase changes connected with the -transition in natural pyrrhotites, etc. The types of distributions of the investigated values of the magnetic properties were also determined. 相似文献
187.
Summary As regards the concept of complete weight p with which an observed quantity (e.g., the direction of theA–G net) should enter the net adjustment, according to Eq.(1), apart from the fundamental weight p
0
), determined by the number of repetitions, it should also contain the time parameter pt according to Eq.(11), where c>1 is a constant, and t is the number of days of observation, and also the refraction factor pr according to Eqs(17, 18), where q is the structural weight of the direction. The condition for being able to determine pr with the directions is observation by means of the three-directional vertex method[2], because it is not possible to localize lateral refraction by angular methods. The theory of complete weight is in favour of observations with a high fundamental weight p
0
which automatically yield higher values of t, and also of pt. The introduction of the complete weight into the experimental directional net in Fig. 2 caused the mean value of the uneliminated refraction error to decrease from 0.24 to 0.12, the mean square error of the adjusted direction being 0.17. The value of the constant c was investigated and the method of determining the parameter pr was derived also for lengths measured electro-optically. Mention is made of the effect of complete weights on the length adjustment of a net in[6]. 相似文献
188.
Zusammenfassung Es wird ein einfaches Modell des zykolnalen Wirbels vorgeschlagen und die Beziehung zwischen seiner Intensität, der Form der Stromlinien und der Deformation der frontalen Grenzoberfläche in seiner Nähe diskutiert. Die Arbeit verfolgt das Ziel, die Kriterien der sogenannten dynamischen Klassifikation der aus den meteorologischen Satelliten photographierten Bewölkung zu finden. 相似文献
189.
Josef Bochníček Jaroslav Šubrt Reviewer M. Hvoždara Reviewer J. Podlešák 《Studia Geophysica et Geodaetica》1971,15(1):76-85
Zusammenfassung Es wird eine Methode für experimentelle Untersuchung der Frequenzkennlinien von Induktionsvariometern mit Aufnahmeschleifen nichttraditioneller Ausmasse beschrieben. Die Grundlage des beschriebenen Verfahrens bildet eine genaue Bestimmung jenes Teils des magnetischen Kraftflusses, der durch die Aufnahmeschleife durchgeht. 相似文献
190.