太古宙和元古宙时期的地壳演化—从地壳地震学获得的证据

通过分析整个世界太古宇和元古宇地区的地震波速模型，发现太古宇地区的厚度为３５ｋｍ左右（碰撞带边缘除外），而元古宇地壳的厚度则显然要大得多，大致为４５ｋｍ，并且在其基底有一较厚的高速层（＞７ｋｍ／ｓ）．我们认为有两种模式可以解释这些差异。第一种模型把这种差异归因于上地幔成分的改变。太古宇地幔中的温度较高，因而导致了科马提熔岩的喷发，结果使得岩石圈过分贫化而不能产生大量的玄武质熔体。元古宇地是在富地幔     

中深中温热液脉系中胶太的金和二氧化硅

中深中温热液金－石英脉的一些结构特征，利用非晶质硅胶（胶体）的早期沉淀来解释可能量合理，这种硅胶随后会结晶成石英。非晶质硅胶可产于在粘滑断裂期间流体压力大大下降的脆性－韧性剪切带中。由于存在有利用的动力学条件，这一过程使热液与非晶质ＳｉＯ２快速达到过饱和，结果是发生非晶质ＳｉＯ２沉淀而不是石英沉淀。降压作用通常也导致流体发生不混溶和可溶金配合物不稳定。但是，胶态ＳｉＯ２的存在却能使交粒稳定，从而使     

在EVGSAU进行在二氧化碳泡沫现场验证试验：IIIC油藏特征描述及注泡…

本文论述了国外９０年代作为坦克动力的大功率高速柴油机的发展现状及其采用的新技术和新结构，预测了其未来的发展趋势，并根据我国国情和对发展趋势的预测，提出了发展我国军车动力应采取的战略措施。     

Persistent organic pollutants (POPs) in a small, herbivorous, arctic marine zooplankton (Calanus hyperboreus): trends from April to July and the influence of lipids and trophic transfer

Samples of Calanus hyperboreus, a herbivorous copepod, were collected (n = 20) between April and July 1998, and water samples (n = 6) were collected in May 1998, in the Northwater Polynya (NOW) to examine persistent organic pollutants (POPs) in a high Arctic marine zooplankton. Lipid content (dry weight) doubled, water content (r2 = 0.88) and delta15N (r2 = 0.54) significantly decreased, and delta13C significantly increased (r2 = 0.30) in the C. hyperboreus over the collection period allowing an examination of the role of these variables in POP dynamics in this small pelagic zooplankton. The rank and concentrations of POP groups in C. hyperboreus over the entire sampling was sum of PCB (30.1 +/- 4.03 ng/g, dry weight) > sum of HCH (11.8 +/- 3.23) > sum of DDT (4.74 +/- 0.74), sum of CHLOR (4.44 +/- 1.0) > sum of CIBz (2.42 +/- 0.18), although these rankings varied considerably over the summer. The alpha- and gamma-HCH and lower chlorinated PCB congeners were the most common POPs in C. hyperboreus. The relationship between bioconcentration factor (BCF) and octanol-water partition coefficient (Kow) observed for the C. hyperboreus was linear and near 1:1 (slope = 0.72) for POPs with a log Kow between 3 and 6 but curvilinear when hydrophobic POPs (log Kow > 6) were included. Concentrations of sum of HCH. Sum of CHLOR and sum of CIBz increased over the sampling period, but no change in sum of PCB or sum of DDT was observed. After removing the effects of time, the variables lipid content, water content, delta15N and delta13C did not describe POP concentrations in C. hyperboreus. These results suggest that hydrophobic POP (log Kow = 3.86.0) concentrations in zooplankton are likely to reflect water concentrations and that POPs do not biomagnify in C. hyperboreus or likely in other small, herbivorous zooplankton.     

一种三维数字高程数据压缩过程

减少数据量将为减少计算机数据储存空间和数据处理时间提供许多便利。本文描述了一种三维数字高程数据压缩过程，文章首先简要地概述了数字地形数据获取的某些方法，与实际试验一起，详细描述了这种新的 过程，提供了本文所建议的算法与目前备择算法的比较研究结果。