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111.
Regions of possible motions are established for dynamical systems possessing time-independent Hamiltonians or for systems which are reducible to that form by means of integrals of the motion using only extended point transformations. The method is applied to the problem of three bodies in a plane and surfaces of zero velocity are found. The governing parameters are the energy, angular momentum and the masses of the participating bodies. The analytical and geometrical properties of these surfaces provide qualitative results for given constants of the motion.  相似文献   
112.
In this paper we report on the MEM power spectrum analysis of brightness temperature fluctuations observed at 2.8 GHz during the total solar eclipse of 16 February 1980. The observed periodicities range from 3.5 min to 64 min. These periodicities may arise due to spatial and/or temporal variations in the solar radio emission. The observed periodicities imply presence of scale sizes ranging from 70,000 to 600,000 km assuming that the brightness fluctuations arise because of spatial variation only. On the other hand, if these fluctuations are due to temporal variation, the observed periodicities correspond well to predicted modes of solar global oscillations.  相似文献   
113.
114.
Glutathione S-transferase activity was measured in the hepatic cytosol front Dissostichus mawsoni and Pagothenia borchgrevinki. Activity measures with 1-chloro-2,4-dinitrobenzene as substrate were 11·2 and 16·7 μmol/min/g tissue respectively. Little or no activity was detected when p-nitrobenzyl chloride or 3,4-dichloro-1-nitrobenzene were used as substrate. The hepatic glutathione S-transferases from D. mawsoni were partially purified using gel filtration and chromatofocusing. Three peaks of activity were resolved. The major isozyme (158-fold purification) eluting at pH7·1 appeared to be catalytically a homodimer. The isozyme was highly inhibited by triphenyltin chloride (IC50 = 0·1 μ) while inhibition constants for Cibicron Blue 3GA, bromosulphophalein and hematin were 1·1, 20 and 34 μ respectively.  相似文献   
115.
The crystal structure of ilinskite, NaCu5O2(SeO3)2Cl3, a rare copper selenite chloride from volcanic fumaroles of the Great fissure Tolbachik eruption (Kamchatka peninsula, Russia), has been solved by direct methods and refined to R 1?=?0.044 on the basis of 2720 unique observed reflections. The mineral is orthorhombic, Pnma, a?=?17.769(7), b?=?6.448(3), c?=?10.522(4) Å, V?=?1205.6(8) Å3, Z?=?4. The The CuOmCln coordination polyhedra share edges to form tetramers that have 'additional' O1 and O2 atoms as centers. The O1Cu4 and O2Cu4 tetrahedra share common Cu atoms to form [O2Cu5]6+ sheets. The SeO3 groups and Cl atoms are adjacent to the [O2Cu5]6+ sheets to form complex layers parallel to (100). The Na+ cations are located in between the layers. A review of mixed-ligand CuOmCln coordination polyhedra in minerals and inorganic compounds is given. There are in total 26 stereochemically different mixed-ligand Cu-O-Cl coordinations.  相似文献   
116.
117.
Recent years have been marked by progress in studying the structure of natural X-ray amorphous substances, anthraxolites included, by scanning electron and atomic power microscopy. Integration of the available data on molecular and supramolecular structure of higher anthraxolites from Karelia, Novaya Zemlya, and the Urals allowed elaboration of new classification criteria for solid bitumen, namely, degree of structure perfection and micromineral composition. This approach will help to eliminate disadvantages of traditional investigation of solid bitumen.  相似文献   
118.
Five representative cumulative samples of basal flows were chemically analysed. Normative composition (CIPW),DI, FI, MI, SI, f (norms) and ‘S’ indices have been calculated therefrom. It is concluded that the Linga flows are tholeiitic in nature with slightly more FeO, MgO and Al2O3 than most tholeiitic basalts. They represent eariy-middle stage basalts with DI less than 30. Thef-norms put these flows in the pyroxene field indicating an early fractionation of pyroxenes causing relative iron enrichment. Textural evidences, also, support a late fractionation of feldspar with overlapping periods of crystallisation of pyroxene and feldspar. The similarity in composition of the lower flows is more apparent than true. The trend of differentiation is characteristically tholeiitic. Oxygen and vapour fugacity may have been responsible for a shift in the general trend of differentiation. Explosive eruption of the magma, which was well mixed and which cooled rapidly, is borne by the features exhibited by these flows.  相似文献   
119.
We have determined the production yields for radionuclides in Al2O3, SiO2, S, Ar, K2SO4, CaCO3, Fe, Ni and Cu targets, which were irradiated with slow negative muons at the Paul Scherrer Institute in Villigen (Switzerland). The fluences of the stopped negative muons were determined by measuring the muonic X-rays. The concentrations of the long-lived and short-lived radionuclides were measured with accelerator mass spectrometry (AMS) and γ-spectroscopy, respectively. Special emphasis was put on the radionuclides 10Be, 14C and 26Al produced in quartz targets, 26Al in Al2O3 and S targets, 36Cl in K2SO4 and CaCO3 targets, and 53Mn in Fe2O3 targets. These targets were selected because they are also the naturally occurring target minerals for cosmic ray interactions in typical rocks. We also present results of calculations for depth-dependent production rates of radionuclides produced after cosmic ray μ capture, as well as cosmic ray-induced production rates of geologically relevant radionuclides produced by the nucleonic component, by μ capture, by fast muons and by neutron capture.  相似文献   
120.
Zusammenfassung Am Südostrand des Münsterländer Kreidebeckens fließen alle größeren Wasserläufe im Bereich der Turonkalke nach NNE oder NE, obwohl das allgemeine Gelände- und Schichtengefälle nach NNW gerichtet ist. Die Ursachen für diese Abweichung sind im Mechanismus der Felserosion zu suchen, der im wesentlichen durch die Eigentümlichkeiten der Karstgerinne und durch die Gesteinszerklüftung bestimmt wird. Bei den Detailuntersuchungen geben sich komplexe Beziehungen zwischen Fließrichtung und Kluftrichtungen zu erkennen.Besonders bedeutend für die Entstehung der NNE gerichteten Täler sind die 170°- und 30°-streichenden Klüfte.
On the south-east border of the Cretaceous basin of Munster, Westfalia, the current directions of streams in the area of Turon-limestone go to NNE or NE, although the main dipping of land surface as well as bedding planes points towards NNW. This divergence is caused by the mechanism of rock erosion, which is determined by peculiarities of subterranean stream channels and joints in limestone. The investigations show complex relations between flow direction and direction of joints.The 170°- and 30°-striking joints are significant of the origin of the NNE direction of the valleys.

Résumé Dans le Turonien au bord sud-est du bassin Crétacé de Münster (Westphalie) toutes les rivières coulent en direction nord-nord-est ou nord-est, quoique la surface morphologique générale et les couches soient penchées en direction nord-nord-ouest. Cette divergence est expliquée par le mécanisme de l'érosion qui dépend principalement des fentes et du caractère des ruisseaux karstiques. Pendant ces études on a pu observer des relations complexes entre la direction des courants et la direction des fentes.Les fentes en direction nord-nord-est (30°) et sud-sud-est (170°) ont considérablement influencé l'origine des vallées.

- - , -. . . , NNE, , 170° 30°.


Herrn Professor Dr.Roland Brinkmann zum 70. Geburtstag gewidmet.  相似文献   
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