点彗台

2010年6月下旬至2010年7月上旬仅发现并命名了3颗彗星。 6月23日,美国宇航局喷气推进实验室的A．Maintzer报告美国广角红外巡天探测卫星（WISE）于2010年6月15日发现一颗新彗星,     

磁场重联实验室模拟进展

磁场重联是空间等离子体和实验室等离子体中的常见现象,被认为是太阳耀斑和磁层亚暴的重要机制。实验室磁场重联的模拟研究已经有二十余年的历史,并且取得了一系列重要的结果。对几个主要的磁场重联实验装置进行了介绍,给出了各个装置的等离子体参数以及产生重联的方法,回顾了实验室研究中和太阳射电密切相关的几个问题。另外,以中国科技大学的线性磁化等离子体装置为基础,建立了国内首个磁场重联的实验装置,研制了实验中需要的诊断工具,并开展了初步的磁场重联实验。     

综合协调时与地方协调时之差

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综合协调时与地方协调时之差

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国际原子时和本地原子时之差

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综合协调时与地方协调时之差

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国际原子时和本地原子时之差

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综合原子时与地方原子时之差

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Rainfall effect on wind waves and the turbulence beneath air-sea interface

Rainfall effects on wind waves and turbulence are investigated through the laboratory experiments in a large wind-wave tank. It is found that the wind waves are damped as a whole at low wind speeds, but are enhanced at high wind speeds. This dual effect of rain on the wind waves increases with the increase of rain rate, while the influence of rainfall-area length is not observable. At the low wind speed, the corresponding turbulence in terms of the turbulent kinetic energy （TKE） dissipation rate is significantly enhanced by rain- fall as the waves are damped severely. At the high wind speed, the augment of the TKE dissipation rate is suppressed while the wind waves are enhanced simultaneously. In the field, however, rainfall usually hin- ders the development of waves. In order to explain this contradiction of rainfall effect on waves, a possibility about energy transfer from turbulence to waves in case of the spectral peak of waves overlapping the inertial subrange of turbulence is assumed. It can be applied to interpret the damping phenomenon of gas trans- fer velocity in the laboratory experiments, and the variation of the TKE dissipation rates near sea surface compared with the law of wall.     

Metallogenic mechanisms of super-large Cu and Au deposits in the Dexing region and simulating experiments

Based on the results of previous studies and under the direction of the theory of “ore deposit genesis”, the authors made use of high temperature and high pressure experimental facilities and conditions at the Tectono-geochemistry Research Room under the State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, and put the focus on the multi-source of tectonically controlling ore-forming materials, the characteristics of multi-stage and multi-episode hydrothermal activities and mineralization and the characteristics of multi-genesis and multi-ore deposition so as to shed light on the metallogenic mechanisms of super-large Cu and Au deposits. In addition simulating experiments were made on multi-stage and multi-episode tectonic activities and rock and ore deformation, multi-stage and multi-episode tectonic activities and mobilization and migration of ore-forming materials, and multi-stage and multi-episode tectonic activities and superimposition and enrichment of ore-forming materials. The experimental results showed that under the action of multi-stage and multi-episode tectonic stress the deformation and fragmentation of not only rocks and ores have been intensified, and but also the ore-forming materials originally disbursed in the rocks and ores have been mobilized and migrated and superimposed and enriched. The experimental results also provided the scientific experimental data and grounds for deep-going research on the rules of metallogenesis and geneses of super-large ore deposits in the Dexing region, Jiangxi Province.