排序方式: 共有3条查询结果,搜索用时 15 毫秒
1
1.
Uda M Sassa S Taniguchi K Nomura S Yoshimura S Kondo J Iskander N Zaghloul B 《Die Naturwissenschaften》2000,87(6):260-263
Some of the pigments painted on the Funerary Stele of Amenemhat (ca. 2000 B.C.) exhibited at the Egyptian Museum, Cairo and
on the walls of the Tomb of Userhat (ca. 1450 B.C.), a rock-cut tomb in Thebes, Egypt, were investigated in situ using both
a convenient home-made hand-held type of X-ray diffractometer and a commercial X-ray fluorescence spectrometer in a complementary
way under touch-free conditions. CaCO3 · 3MgCO3 (huntite) was found in the white-painted parts of these two ancient monuments. An arsenic (As)-bearing phase was detected
in the yellow-painted parts of the latter monument. The occurrence of huntite in Egypt has not been reported previously.
Received: 8 October 1999 / Accepted in revised form: 10 March 2000 相似文献
2.
To examine the growth-selective survival in early life stages of jack mackerel from the East China Sea, we compared growth rates of young fish collected from the surface layer in April with those of survivors collected from the near-bottom layer in May?CJune. We performed this analysis from 3?year classes with different levels of relative abundance: low in 2005, intermediate in 2008 and high in 2009. Growth rates during the larval stage of the original population were slower than the survivors in all survey years, indicating that faster-growing individuals in the surface layer had a higher probability of survival to the near-bottom habitat than slower-growing individuals. Selection intensity, defined as differences in growth rates between the two groups, was higher in year classes with a lower abundance. Hence, growth rates during the early life stages of jack mackerel are considered to be a critical determinant of successful survival to the demersal habitat. 相似文献
3.
We examined larval mesopelagic fish assemblages, their distribution, and seasonal occurrence patterns in the Kuroshio–Oyashio
transition region of the western North Pacific where complex hydrographic structures are observed due to the confluence of
the Kuroshio Extension and Oyashio current. Larvae of the dominant families Myctophidae, Gonostomatidae, Bathylagidae, Sternoptychidae,
and Phosichthyidae were represented by 31 species or types belonging to 24 genera. Based on species composition analysis using
the Morishita–Horn similarity index, five assemblages were recognized: Oyashio, Spring Transition, Summer Transition, Kuroshio,
and Slope Water assemblages. The distribution patterns of these assemblages corresponded closely with hydrographic structures
such as position of the Oyashio and Kuroshio Extension fronts, warm core rings and streamers. Spring Transition (April) and
Summer Transition (July–October) assemblages were the most important larval assemblages in the transition region. Larval abundances
were low during late autumn and winter. The Spring Transition and Summer Transition assemblages were composed of subtropical,
transitional, subarctic, and slope-water species, suggesting the importance of the transition region as nursery grounds of
mesopelagic fishes of various origins from subarctic to subtropical waters. Larval fish transport by the Kuroshio, Oyashio,
and Tsugaru Warm currents into the transition region is discussed. 相似文献
1