新型的自动标定器

介绍了一种新型的自动标定装置,阐述了簧板标定器的基本工作原理及其自动控制系统,该装置结构简单,可方便地组合成人工和自动标定器。给出了簧板标定器的初步测试结果,表明簧板标定器完全满足形变仪器的要求。     

SS-Y型短基线伸缩仪及其标定装置

介绍了SS Y型短基线伸缩仪总体设计思想、整体结构和主要部件的工作原理及台站试验情况。试验结果表明 ,由于使用含铌特种因瓦棒 (为基线 )和高灵敏度的换能器、精密超微量标定平台以及有效的操作系统 ,在缩短基线的条件下 ,保持了高精度与高稳定性 ,在NS分量不大于 6m、EW分量不大于 10m的基线上 ,能记录到清晰的应变固体潮汐 ,其观测精度优于现有台站的观测水平 ,并彻底地解决了石英管炸裂、汞泄漏污染现象 ,同时 ,智能化记录控制器提高了自动化程度。     

SS-YD型断层观测伸缩仪

介绍了SS YD型断层观测伸缩仪的系统组成及其基本原理。该系统实行现场自动采集和自动储存并由“数据交换器”进行数据调用和回放 ,具备交直流电源自动转换及有效的避雷装置 ,实现了无人值守。仪器所得观测数据稳定 ,并记录到清晰的应变固体潮汐与台湾“9.2 1”大地震 0 .5 μm的同震阶跃     

The effect of the Jessica grounding on Galápagos reef fish communities adjacent to the wreck site

The grounding of the oil tanker Jessica off San Cristóbal Island, Galápagos, resulted in generally elevated rather than depressed densities of fishes adjacent to the wreck site 15 weeks post spill. Species richness of fishes declined along transects out from the wreck; however, patterns were inconsistent for different depth strata, with the most clearly defined decline evident for the intermediate 5-7 m depth stratum. Fish species attracted to the immediate wreck site, most notably the surgeonfish Prionurus laticlavius, the damselfish Microspathodon dorsalis and the angelfish Holacanthus passer, were considered to be responding either to the heterogeneity provided by the wreck structure or elevated densities of macroalgae. The fish community at the wreck site lay outside the range of variation for other sites investigated in the region; however, contrary to predictions of grounding impacts, the fish assemblage immediately adjacent to the wreckage showed greater faunal similarity to reference sites than did fish assemblage at 60-90 m distance from the grounding.     

Comparing bleaching and mortality responses of hard corals between southern Kenya and the Great Barrier Reef, Australia

We compared the bleaching and mortality response (BMI) of 19 common scleractinian corals to an anomalous warm-water event in 1998 to determine the degree of variation between depths, sites, and regions. Mombasa corals experienced a greater temperature anomaly than those on the Great Barrier Reef (GBR) sites and this was reflected in the greater BMI response of most taxa. Comparing coral taxa in different sites at the same depth produced high correlation coefficients in the bleaching response in Kenya at 2 m (r=0.86) and GBR at 6 m depth sites (r=0.80) but less in the GBR for shallow 2 m sites (r=0.49). The pattern of taxa susceptibility was remarkably consistent between the regions. Coral taxa explained 52% of the variation in the response of colonies to bleaching between these two regions (Kenya BMI=0.90 GBR BMI+26; F(1,19) - 18.3; p < 0.001; r2 = 0.52). Stylophora and Pocillopora were consistently susceptible while Cyphastrea, Goniopora Galaxea and Pavona were resistant in both regions. Three taxa behaved differently between the two regions; Acropora, and branching Porites were both moderately affected on the GBR but were highly affected in Kenya while the opposite was true for Pavona. These results suggest that a colonies response to bleaching is phylogenetically constrained, emphasizing the importance of features of the host's physiology or morphology in determining the response to thermal stress.     

A study of C3HD in cold interstellar clouds

We have detected the 1(10)-1(01) transition of C3HD at 19.418 GHz at twelve positions in cold, dark clouds and resolved the D hyperfine components in two sources (L1498 and TMC-1C) well enough to derive values for the D quadrupole coupling constants. Simultaneous observations of C3H2 in each source yield relative integrated line intensities in the range 0.10-0.18, from which we derive relative [C3HD]/[C3H2] abundances in the range 0.05-0.15. These are among the highest deuteration ratios yet observed. Within the limits of the observational and modeling uncertainties it is possible to explain the derived [C3HD]/[C3H2] ratios by ion-molecule chemistry if [e-] approximately 3 x 10(-7).