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111.
V. Kupčik 《Mineralogy and Petrology》1984,32(4):259-269
Zusammenfassung Die Kristallstruktur des zuerst vonPaar, Chen undMeixner beschriebenen neuen Minerals wurde an der Originalprobe bestimmt. Für die prinzipielle Lösung der Struktur war eine Kombination von direkten und Pattersonmethoden erforderlich. Anhand von 2774 kristallographisch unabhängigen Röntgenreflexen (davon 1828 beobachtet) wurde die Struktur bis zu einem gewichtetenR-Wert von 10.7% isotrop verfeinert. Das Mineral ist orthorhombisch, RaumgruppePnma mit den Gitterkonstantena
0=54.76Å,b
0=4.030 Å,c
0=22.74 Å undZ=4. Die Kristallstruktur ist durch galenitähnliche Bereiche, deren [110] Richtung parallel zurb
0-Achse verläuft, gekennzeichnet. Die gegenseitige Anordnung dieser Bereiche ist teils kobellit-, teils cosalitähnlich. Die galenitähnlichen Bereiche sind vorwiegend wismuthhaltig (Koordination 3+2+1), während die Ph-Atome in einer trigonal-prismatischen Koordination mit 2 zusätzlichen Schwefelatomen vorwiegend als Bindeglieder dazwischen liegen.
Mit 3 Abbildungen
Herrn Professor Dr.Josef Zemann zum 60. Geburtstag gewidmet. 相似文献
The crystal structure of eclarite, (Cu,Fe)Pb9Bi12S28
Summary The crystal structure of the new mineral eclarite, first described byPaar, Chen andMeixner was determined using the original material. It was necessary to apply a combination of direct and Patterson methods. The structure was refined for 2774 independent reflections (1828 observed) with isotropic temperature factors to a weightedR-value of 10.7%. Eclarite crystallizes in the orthorhombic space groupPnma with lattice parametersa 0=54.76 Å,b 0=4.030 Å,c 0=22.75 Å,Z=4. The structure is characterized by galena-like building units with [110] (galena) parallel to theb-axis. These units are linked to each other partly as in kobellite, partly as in cosalite structures. Bi prefers to occupy the metal positions in the galena-like units, coordinated by 3+2+1S, whereas Pb occupies preferably the positions coordinated trigonal prismatic with two additional S. The latter groups serve to connect the galena-like units.
Mit 3 Abbildungen
Herrn Professor Dr.Josef Zemann zum 60. Geburtstag gewidmet. 相似文献
112.
A statistically relevant correlation between the reaction rate coefficient, k
OH, for the OH radical reaction with 161 organic compounds in the gas phase at 300 K, and the corresponding vertical ionisation energies E
i,v, reveals two classes of compounds: aromatics where –log(k
OH/cm3s-1)3/2E
i,v(eV)–2 and aliphatics where –log(k
OH/cm3s-1)4/5E
i,v(eV)+3. The prediction of the rate coefficient, k
OH, for the reaction of OH with organic molecules from the above equations has a probability of about 90%. Assuming a global diurnal mean of the OH radical concentration of 5×105 cm3, the upper limit of the tropospheric half-life of organic compounds and their persistence can be estimated. 相似文献
113.
114.
The paper considers a puff diffusion in its inertial stage when particle separation obeys the laws of the inertial subrange and depends only on eddy energy dissipation rate . The can be determined in the surface layer by the turbulent kinetic energy equation. Similarity equations connect with diffusion measure .A simple analytical model has been deduced to estimate pollutants diffusion during calms. 相似文献
115.
Summary An attempt is made to show possible ways of predicting radio wave absorption in the midlatitude lower ionosphere using relations between absorption and the intensity of solar ionizing radiation and/or common solar activity indices, and between absorption and f0F2.
aa mu nuau nu a¶rt;u ¶rt;um u u a mu ¶rt; nu u umum uuu uu (uu uu u¶rt;au amumu) u ¶rt; nu u f0F2.相似文献
116.
Summary The data on geopotential heights and temperatures at 7 pressure levels between 1000-10 hPa above Berlin(52.5 °N, 13.4 °E) are analysed for the winters of 1963–1973. No demonstrable effect of the interplanetary magnetic field sector boundary crossing (IMF SBC) is found in the lower and middle stratosphere, but there is a demonstrable effect in the middle troposphere at the 500 hPa level. This effect is less important than the IMF SBC effect in the tropospheric vorticity area index and seems to be of a different type.
auum ¶rt;a nnmua m u mnam a 7 nm ¶rt;au ¶rt; 1000-10 a a¶rt; u(52,5 °.., 13,4 °.¶rt;.) ¶rt; u 1963–1973. ua ¶rt;aam m nu mau nam aum n( ) ¶rt;a amu u u ¶rt; mam, ma m a¶rt; ¶rt; mn a 500 a. mm m a, m u¶rt; na¶rt;u aumu am, u am m ¶rt; muna.相似文献
117.
Summary The dependence of Pn-wave velocities on the heat flow, temperature at the crustmantle boundary and the thickness of the Earth's crust in Europe was investigated in relation to the problem of lateral inhomogeneities in the upper mantle. A map was constructed of the distribution of Pn-wave velocities on the territory of Europe. The relations these investigations yielded, were compared with the results of laboratory experiments and all the results are discussed from the physical point of view. The conclusion drawn is that that temperature and pressure effect provide a sufficient explanation of the observed regional changes of Pn-wave velocities for the European continent.
auum ¶rt;auu mu n¶rt; ¶rt; nmu uua (Pn) u mn nm, mnam a nmu amuu u m a mumuu n a u¶rt;aa u numa ¶rt;¶rt;m amuu. mumuu n a maa a uu m Pn- a nmu uua. u¶rt;u umam ¶rt;a mama aam u¶rt;au uuu m n¶rt; amuu u u ¶rt;au u mnam mmmm mama n¶rt;aa am. ¶rt;a ¶rt;, m ua uu m Pn- a n mum ¶rt;mam um uuu mnam u ¶rt;au a nmu uua.相似文献
118.
Summary The magnetic susceptibility of quartz single crystals is diamagnetic (–14×10
–6
in SI units) and exhibits only very small anisotropy (mostly less than 1%); thus the susceptibility of the quartz matrix in quartzite can be regarded as virtually isotropic. Owing to the influence of the negative and isotropic susceptibility of the quartz matrix, the degree of anisotropy of quartzite, as inferred from model calculations, is higher than that of the ferrimagnetic fraction. This influence is very strong if the mean susceptibility of quartzite is in the vicinity of zero.
uma aa m ¶rt;uaaumu (nuuum–14 × 10 –6 um ) u a aumnuu ( 1%). m aum, m nuuum a a auma m m numa namuu umn. amamu ¶rt;uau ¶rt;m, m n nuu uu muam u umn nuuumu a a mn aumnmu auma , mn aumnmu aum auu. m uu au m¶rt;a, ¶rt;a ¶rt;a nuuum ua .相似文献
119.
Anomalous induction across Europe 总被引:1,自引:0,他引:1
Summary Using real induction vector data, collected at 958 European observation sites, together with our data from the Bohemian Massif and the West Carpathians, we have generated a contour map of the transfer function TF1 (corresponding to transfer function A in Wiese's relation). Only the zero contour is retained and shown on the map. It clearly marks the main anomalous induction zones, related to internal structural inhomogeneities, across Europe. 相似文献
120.
Summary The total ozone response to strong major geomagnetic storms (Ap≥60) in winter along the 50° N latitudinal circle is studied. The results add to the recent results of Laštovička et al. (1992)
obtained for European middle latitudes (∼50°N) and to the results of Mlch (1994). A significant response of total ozone is
only observed in winter under high solar activity/E-phase of QBO conditions (E-max) and seems to be caused by geomagnetic
storm-induced changes of atmospheric dynamics. There are two sectors along latitude 50°N, which are sensitive to forcing by
geomagnetic storms both in total ozone and the troposphere — north-eastern Atlantic-European and eastern Siberia-Aleutian
sectors. The total ozone response under E-max conditions manifests itself mainly as a large decrease in the longitudinal variation
of ozone after the storm, which means an increase of ozone in Europe. The observed effects in total ozone consist in redistribution,
not production or loss of ozone. 相似文献