C岩体的铁镍磁铁矿和镍、镁、钛、铬四种磁铁矿相互间的关系

The ferroan-trevorite reported in this paper occurs in serpentinite massif, Sonthwestern China. 3.4--8.8 per cent of nickel, but no titanium, were detected by microprobe analysis in different grains. The reflectivity of ferroan-trevorite is 20.2---20.9 (590nm), microhardness Ht=541-610 kg/mm^2 (load 50g),α0 =8.38A. Titanium magnetite from L-Intrusive, Southwestern China, and from other intrusives of the world, may contain considerable amounts of chromium and magnesium,but no nickel, if any, has been found.     

1987年9月23日昆明日偏食在波长10.6厘米的观测

1987年9月23日日环食,在昆明看到的是偏食。本文对云南天文台10.6厘米观测资料进行了处理,得出了活动区、暗条、日珥、谱斑上空射电源流量、二维角径大小、高度和亮温度。谱斑上空晕的辐射标度N~2L=6.3～6.9×10~(28)电子数~2/厘米~5。     

三波段太阳射电快速记录系统时间同步装置简介

本文主要介绍时间同步装置的构成、实现方法及其软件设计。     

三波段太阳射电高时间分辨率同步观测系统简介

本文主要介绍同步观测系统的总体结构,软件系统的主要特征,硬件功能及试观测结果。     

Improved water table dynamics in MODFLOW

The standard formulation of a block-centered finite-difference model, such as MODFLOW, uses the center of the cell as the location of a cell node. Simulations of a dynamic water table can be improved if the node of a cell containing the water table is located at the water table rather than at the center of the cell. The LPF package of MOD-FLOW-2000 was changed to position a cell's node at the water table in convertible cells with a water table. Improved accuracy in the upper regions of an unconfined aquifer is demonstrated for pumping from a partially penetrating well. The change introduces a nonlinearity into the solution of the flow equations that results in slightly slower convergence of the flow solution, 7% slower in the presented demonstration. Accuracy of simulations is improved where vertical flow is dominated by a moving water table, but not when a large water table gradient dominates over the water table movement.     

地质体三维可视化建模的技术方法研究

地质体三维可视化模型具有形象、直观、动态、准确、信息丰富等特点,在指导地质找矿和矿山开发等方面具有很大的优势及实用价值。文章对地质体三维可视化建模的整个技术方法流程作了总结性阐述,并分析其技术关键,同时还进一步探讨了模型的分类及其应用。     

双Packer系统在鄂尔多斯盆地地下水勘查中的应用

双Packer系统在鄂尔多斯盆地地下水勘查中的应用,为在该盆地开展深层地下水水化学同位素的研究,提供了一个有效的工具。了解该系统的工作原理、应用条件和在鄂尔多斯盆地地下水勘查中的具体应用,对在我国水文界普及该技术具有重要意义。     

Effects of 12 years' operation of a sewage treatment plant on trace metal occurrence within a Mediterranean commercial sponge (Spongia officinalis, Demospongiae)

The present field study uses Spongia officinalis for assessing trace metals occurrence in time and space within Mediterranean rocky communities. Nine sites were selected in the Marseille area for studying spatial trends in 12 metal concentrations. Long term changes in 8 metal concentrations were assessed at sites that had been sampled before and 12 years after the opening of a treatment plant. Spongia officinalis highly concentrated all the trace metal surveyed excepted Hg and Cd. The overall contamination level registered provided a classification of the study sites which is congruent with that given by other studies on pollutant accumulation in neighbouring sandy-bottoms or benthic assemblages. Among the metals studied, Fe, Pb, Cr are those that best highlighted a pollution gradient. In the present study, only Cd concentration did not vary in space. Except for Ni, all pollutant concentrations clearly decreased between 1984 and 1999. This very impressive decrease in heavy metal concentrations within the Marseille area represents an indisputable evidence of the improvement of the seawater quality resulting from 12 years' operation of the Marseille sewage plant. Moreover, the significant decrease also recorded in the reference population at Port-Cros might reflect an overall improvement in the seawater quality of the NW Mediterranean.