A study on the flux,speciation, and budget of mercury in controlled experimental ecosystems

The lowest addition of mercury (0.1 ug Hg 1⁻¹) was used in CEEs for research on mercury flux, speciation and budget. The removal behavior of mercury by phytoplankton in water columns of CEEs can be described by first order kinetic equations for total and particulate mercury in the CEE spiked by mercury. The removal rate of mercury in water columns depends on the size and productivity of phytoplanton in a water column to which mercuric ions were added. A 4.4 day half-life time and a 2.8 day half-life time for total and particulate mercury respectively was obtained in diatom bloom. During microflagellate bloom a 30 day total mercury half-life time was estimated with increase of particulate mercury in the water column. The 0.010 ug Hg cm⁻²y⁻¹ mercury flux rate that was attained in the control bag agreed with the values from field measurements in Saanich Inlet where the bags were launched. The proportion of total mercury to dissolved and particulate mercury depended also on the size, productivity, and concentration of mercury in a water column. A more or less constant distribution of mercury species in the control bag was observed as follows: dissolved Hg 0.73, particulate Hg 0.27, inorganic Hg 0.42, dissolved organic Hg 0.31. After spiking with mercury, the particulate mercury rose rapidly and reached to over 70% of the total mercury. The concentration factor of mercury by phytoplankton in the CEEs in the order of 10⁵ was consistent with the results from field measurements in Saanich Inlet. The mercury recovery from the water column, sediment, water with sediment, and the CEE bag walls was only 52.3% of total mercury spiked in the CEE. The losses of mercury by vaporization into the ambient air and diffusion through the wall of the enclosure should be considered. This paper was published in Chinese inOcean. Limn. Sinica,17(4):307–317, 1986.     

宇宙常数Λ≠0的平面引力波

本文讨论了宇宙常数Λ≠0时的平面引力波问题。在弱场近似下,得到了平面引力波传播方程及色散方程。通过对Kretschmann曲率标量的讨论发现,不同于Λ=0时h_(μv)仅有横场这一众所周知的结果,Λ<0时不存在一个坐标系,使h_(μv)的标量场、纵场、混合场分量全为零。最后讨论引力波辐射,结论是与Λ=0时无偶极辐射这一结果不同,Λ<0时,混合场的辐射有偶极辐射。     

地形对南北低空气流重力惯性波稳定度的影响

在南北向低空急流下,通过简单二层模式讨论地形起伏对重力惯性波的影响,研究指出:(1)存在一个对重力惯性波稳定度无影响的函数和不产生不稳定重力惯性波地形函数;(2)地形起伏越大,不稳定重力惯性波越强;(3)无论南风或北风基流,都是南坡比北坡更有利于产生不稳定重力惯性波。最后,通过实例计算表明,动力分析结果与实况有较好的一致性。     

新的γ射线脉冲星PSR1055－52的COS－B证认

本文利用ＣＯＳ－Ｂ卫星观测资料对ＣＧＲＯ卫星新近发现的一颗γ射线脉冲星进行了守时性分析，得到了显著的周期结构。这个结果对ＰＳＲ１０５５－５２是一颗γ射线脉冲星提供了新的、独立的证认，本文对普遍公认的六颗γ射线脉冲星也作了比较和讨论。     

Towfish orientation and position estimation

The towfish location and orientation problems that arise in using side-scan sonar to detect objects on the sea bottom are treated separately. Data which locate the towfish relative to the ship are usually deteriorated by multipath receptions and other effects. In order to overcome this serious degradation in the location measurements, a modified Kalman filter is proposed. An estimate of the state transition matrix for this filter is derived, and a means of switching between two Kalman gains is suggested. The feasibility of the proposed filter is justified by a case study. Improved estimates of towfish pitch and heading measurements are obtained by a separate system employing model identification and subsequent Kalman filtering. Application of these methods to data from similar towed side-scan sonar systems should yield significant gains in object location accuracy     

一种无线数据传输接口及控制装置

本文介绍一种无线数据传接口及控制装置。装置中采用计算机软件实现串—并、并—串变换及频率调制、其硬件成本低廉,工作可靠,可用于速率为50、300、600或1200bps的数传通信。     

The environmental quality of the sewage discharge area of Qingdao Cove—A cladistic analysis

This study on the environmental quality of the Qingdao Cove intertidal zone sewage discharge area is based on data obtained from the December of 1989 and 1990 macrobenthos investigations there, and uses pollution indicator species and computer aided cladistic analysis to divide the area into a polluted area and a semipolluted area. The study showed the environmental quality in 1990 improved over that in 1989. Project supported by the National Natural Science Fonndation of China     

Gamma—Ray Bursts：Afterglows and Central Engines

Gamma-ray bursts (GRBs) are the most intense transient gamma-ray events in the sky; this, together with the strong evidence (the isotropic and inhomogeneous distribution of GRBs detected by BASTE) that they are located at cosmological distances, makes them the most energetic events ever known. For example, the observed radiation energies of some GRBs are equivalent to the total convertion into radiation of the mass energy of more than one solar mass. This is thousand times stronger than the energy of a supernova explosion. Some unconventional energy mechanism and extremely high conversion efficiency for these mysterious events are required. The discovery of host galaxies and association with supernovae at cosmoligical distances by the recently launched satellite of BeppoSAX and ground based radio and optical telescopes in GRB afterglow provides further support to the cosmological origin of GRBs and put strong constraints on their central engine. It is the aim of this article to review the possible central engines, energy mechanisms, dynamical and spectral evolution of GRBs, especially focusing on the afterglows in multi-wavebands.     

Research on regional comprehensive development in developed regions —The case of Shanghai-Nanjing-Hangzhou area

The developed regions are faced with the problems of regional comprehensive development, and the research on regional comprehensive development has become a trend in the world. To optimize regional industrial structure and to select and determine scientifically the spatial development strategy of regional industries are the central themes to be solved for the research on regional comprehensive development in the developed regions. This paper proposed the basis for optimizing regional industrial structure, and the main factors of selecting and determining the regional leading industries. Based on this, the paper puts forward the leading industries and the spatial development strategy in Shanghai-Nanjing-Hangzhou area in the future ten or more years. Combined with the situation of Shanghai-Nanjing-Hangzhou area, the paper also discusses some problems of locating superior developing axis to benefit the rational distribution of regional productive forces.