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441.
442.
Remnants of the Last Interglacial shoreline occur at Middle Lagoon on the far south coast of New South Wales. Relict beach sediments can be traced to a height of at least +4.8 m and are indicative of a former mean sea level of about +3 m. Thermoluminescence (TL) ages of 126 ± 13 ka and 114 ± 15 ka were determined for beach and aeolian facies respectively. Sands in the lower part of an exposure on the adjacent Gillards Beach gave TL ages of 108 ± 13 ka, but sands in the upper part of that exposure gave an age of 19.9 ± 3.5 ka. This chronological evidence of a stratigraphic unconformity in what was initially taken as pedogenic differentiation at Gillards Beach is supported by contrasting electron traps and colour centres in crystal lattices of quartz grains in these two samples. No tectonic displacement is apparent. This site provides the first evidence of the Last Interglacial sea level for 1000 km along the coast between Gippsland and Newcastle. 相似文献
443.
G. V. Triantaphyllidis T. J. Abatzopoulos R. M. Sandaltzopoulos G. Stamou C. D. Kastritsis 《International Journal of Salt Lake Research》1993,2(1):59-68
Cysts of two parthenogeneticArtemia strains from the Kalloni and Polychnitos saltworks on Lesbos Island were evaluated for their potential use in aquaculture.
The characterizations performed were: cyst and naupliar biometrics, cyst hatching characteristics, and fatty acid profile
of instar-I nauplii. Deactivation of diapause after treatment with H2O2 and/or decapsulation were applied in order to improve cyst hatchability. The evaluation revealed that the strains studied
exhibit acceptable hatching characteristics for parthenogeneticArtemia and that the fatty acid profile of the Kalloni strain is excellent for use in culturing marine fishes and crustaceans. Statistical
analyses on cyst and naupliar biometrics showed that the two populations characterized are almost identical and very similar
to other Greek parthenogenetic strains. 相似文献
444.
The development and first tests of a novel method for the direct, sensitive, selective, and fast detection of gaseous nitric acid in air are described. The detection method is based on the laser-photolysis fragment-fluorescence (LPFF) method using 193 nm (ArF) laser light. The photolysis process yielding OH fluorescence has been thoroughly investigated. Up to now, the method has been found to be practically free of interferences. The mixing ratio for nitric acid is measured on-line with a detection limit of about 0.1 ppbv for an accumulation time of the signal of 10–15 min. A number of tests and field measurements were performed to demonstrate the feasibility and limits of the described detection method. 相似文献
445.
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The warm pool in the Indian Ocean 总被引:2,自引:0,他引:2
The structure of the warm pool (region with temperature greater than 28°C) in the equatorial Indian Ocean is examined and
compared with its counterpart in the Pacific Ocean using the climatology of Levitus. Though the Pacific warm pool is larger
and warmer, a peculiarity of the pool in the Indian Ocean is its seasonal variation. The surface area of the pool changes
from 24 × 106 km2 in April to 8 × 106 km2 in September due to interaction with the southwest monsoon. The annual cycles of sea surface temperature at locations covered
by the pool during at least a part of the year show the following modes: (i) a cycle with no significant variation (observed
in the western equatorial Pacific and central and eastern equatorial Indian Ocean), (ii) a single maximum/minimum (northern
and southern part of the Pacific warm pool and the south Indian Ocean), (iii) two maxima/minima (Arabian Sea, western equatorial
Indian Ocean and southern Bay of Bengal), and (iv) a rapid rise, a steady phase and a rapid fall (northern Bay of Bengal). 相似文献
447.
吉林省南部下元古界集安群地质特征与沉积期古环境分析 总被引:5,自引:0,他引:5
根据集安群地质特征,岩石化学,稳定同位素特征分析认为:蚂蚁河组沉积期古环境为强氧化泻湖相;荒岔沟组沉积期为强还原的泻湖相、大东岔组沉积期为开阔正常浅海潮坪相。集安群从发生发展到结束古环境演化规律是:构造上,由优地槽向冒地槽演化,气候上由炎热向温湿演化;古地理环境从有障壁的局限海变为无障壁的开阔海;从咸化海向正常海,从泻湖相向潮坪相转化。 相似文献
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