PHYSICAL MODEL FOR SMALL SCALE SANDWAVES MIGRATION IN NORTH GULF OF SOUTH CHINA SEA

The aim of this paper is to investigate the mechanism of small scale sand-wave migration. According to the environmental characteristic of the north gulf of South China Sea, a quasi-3D mechanics model has been built for simulating the small scale sand wave migration. The calculation results are shown to be consistent with the observed data in the trough of sand ridge. Considering the effect of environmental actions and sand wave features, we develop an effective formula to predict sand-wave migration. It is indicated that the physical models should be used to predict the migration of the small scale sand-wave, which is rarely dominated by wave activity.

What triggers the transition of palaeoenvironmental patterns in China；the Tibetan Plateau uplift or the Paratethys Sea retreat?

IEECAS SKLLQG

Sea surface temperature reconstruction for the middle Okinawa Trough during the last glacial-interglacial cycle using C-37 unsaturated alkenones

IEECAS SKLLQG

Study on bioactivity of extracts from marine sponges in Chinese Sea

The bioactivity screening of fractions from two inter-tidal sponges collected from the north of China Yellow Sea and one sponge collected from the South Chinese Sea was reported in this study. In sponge Hymeniacidon perleve there were 9 fractions out of 15 from CHCl3 extract with anti Staphylococcus aureus activity, 9 fractions out of 19 from BuOH extract with anti Escherichia coli activity, and three fractions from CHCl3 extract which had moderate to strong activity in inhibiting Bacillus subtilis, Candida albicans, and Aspergilus niger. The fractions of Reniochalina sp. showed bioactivity against bacteria and fungi. The fractions of Acanthella acuta Schmidt showed bioactivity against S. aureus and fungi. One compound from H. perleve obtained by the bioactively directing isolation was tested for bioactivity against the human hepatoma cell line Qgy7701 (IC50 10.1 mug/ml), Burkitt's lymphoma cell line Raji (IC50 9.76 mug/ml) and chronic myelogenous leukemia K562 (IC50 1.90 mug/ml). (C) 2003 Elsevier B.V. All rights reserved.