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141.
G. S. Ripp A. G. Doroshkevich M. V. Badmatsyrenov N. S. Karmanov 《Geochemistry International》2007,45(6):538-545
The composition and nature of high-Cr minerals in lithic clasts from the carbonatites of the Veseloe occurrence, northern Transbaikalia, were considered. In order to determine their source, the Cr-bearing phases were compared with chromite, magnetite, and rutile from ultrabasic rocks, mantle xenoliths, and eclogites. It was suggested that the xenoclasts studied were formed at great depths, whereas the carbonatites were directly derived from the mantle rather than formed by the crustal differentiation of a silicate-carbonate melt. 相似文献
142.
James M. Stroh 《Contributions to Mineralogy and Petrology》1976,54(3):173-188
The addition of Fe and Cr to the simple system MgO-SiO2-Al2O3 markedly affects the activities of phases involved in the equilibrium
\textMg\text2 \textSiO\text4 \text + MgAl\text2 \textSiO\text6 \text = MgAl\text2 \textO\text4 \text + Mg\text2 \textSi\text2 \textO\text6 \textOlivine + Opx\textsolid solution \text = Spinel + Opx\textsolid solution \begin{gathered} {\text{Mg}}_{\text{2}} {\text{SiO}}_{\text{4}} {\text{ + MgAl}}_{\text{2}} {\text{SiO}}_{\text{6}} {\text{ = MgAl}}_{\text{2}} {\text{O}}_{\text{4}} {\text{ + Mg}}_{\text{2}} {\text{Si}}_{\text{2}} {\text{O}}_{\text{6}} \hfill \\ {\text{Olivine + Opx}}_{{\text{solid solution}}} {\text{ = Spinel + Opx}}_{{\text{solid solution}}} \hfill \\ \end{gathered} 相似文献
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147.
The transition 111 ? 110 at 4.829 GHz of formaldehyde (H2CO) was the first one showing the anomalous absorption, i.e., the absorption against the cosmic microwave background. Anomalous absorption is an unusual phenomena. Structure of H2CC is very similar to that of H2CO and H2CS. Both H2CO and H2CS have already been identified in a number of cosmic objects. Though H2CC is not yet identified in the cosmic objects, we propose that H2CC may be identified in cool cosmic objects through its transition 111 ? 110 at 4.85 GHz in anomalous absorption. 相似文献
148.
Manufactured and tested in his work is a photoelectric device that makes it possible to automatically determine the relative angular position of the beam of a miniature torsion balance, angular readings being discretized with various time step values and stored in a computer. Measurements were taken with this device that captured the occurrence of the partial solar eclipse on September 11, 2007, and confirmed the fact, established previously through visual observation, that the position of torsion balance beams changed at the instant an eclipse took place. 相似文献
149.
The area of sea subjected to heated effluent discharged from the power station at Piombino is very suitable for the study of problems connected with thermal pollution of the nearshore environment. Construction of the power station is planned to go ahead by successive operational stages, producing correspondingly increased amounts of heat discharged into the marine environment. At present it produces 640 MW and discharges 190 Mcal s?1 into the sea.This paper studies the benthic communities after the power station had been operating for about 1 yr. Comparison of these data with those about subsequent operational stages will presumably allow to establish to what extent the environment can receive, without damage, increasing amounts of heat. 相似文献
150.
An analysis is made of the results from all repeated gravity measurements of the Fennoscandian land uplift gravity line 63°. The line is, thereby, divided into two separate parts: one part west of the land uplift maximum, and the other part east of the land uplift maximum. A statistically significant change of gravity is found both for the western part and the eastern one. Both parts give a relation between gravity change and land uplift of about ?0.22μgal/mm. 相似文献
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