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当前解决安全生产已成为油田工作的重中之重,随着GIS行业的快速发展,先进的二三维联合展示手段、基于位置的资源管理分析等特有技术已经开始在实际应急中发挥作用。本文将从几个方面介绍SuperMap二三维一体化GIS技术在油田设备安全应急的几个领域中的应用,包括设备安全预警、应急资源可视化管理、二三维动态安全预警、三维安全应急预案模拟等,将GIS分析算法、三维粒子特效、三维动画特效融入到我们的安防系统中,达到既实用又逼真的效果。 相似文献
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We studied the effects of mercury (Hg2+) on antioxidant and digestive enzyme activities in terms of LC50 value and on hepatopancreas histostructures of juvenile Chinese mitten crabs Eriocheir sinensis in 40-day exposure to various concentrations of Hg2+ (0, 0.01, 0.05, 0.10, 0.20, and 0.30 mg/L). The results show that the activities of superoxide dismutase (SOD), glutathione
peroxidase (GPX) and catalase (CAT) significantly increased in the concentrations of 0.01 and 0.05 mg/L, while that of enzyme
decreased in 0.10, 0.20 and 0.30 mg/L treatments. Meanwhile, Hg2+ disrupted the histostructures of the hepatopancreas, causing decreases in activities of pepsin, tryptase, amylase, and cellulose,
which are synthesized in the hepatopancreas. Moreover, as the Hg2+ concentration increased, the survival rate of the crabs decreased, worst at 56.57% in 0.30 mg/L. Therefore, although crabs
are able to tolerate low levels of mercury pollution, high levels lead to cellular injury and tissue damage in hepatopancreas,
which then loses some of its vital physiological functions such as absorption, storage, and secretion. 相似文献
25.
Studies in the coastal area of Bohai Bay,China,from July 2006 to October 2007,suggest that the method of meiofaunal biomass estimation affected the meiofaunal analysis.Conventional estimation methods that use a unique mean individual weight value for nematodes to calculate total biomass may cause deviation of the results.A modified estimation method,named the Subsection Count Method (SCM),was also used to calculate meiofaunal biomass.This entails only a slight increase in workload but generates results of g... 相似文献
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Studies in the coastal area of Bohai Bay, China, from July 2006 to October 2007, suggest that the method of meiofaunal biomass
estimation affected the meiofaunal analysis. Conventional estimation methods that use a unique mean individual weight value
for nematodes to calculate total biomass may cause deviation of the results. A modified estimation method, named the Subsection
Count Method (SCM), was also used to calculate meiofaunal biomass. This entails only a slight increase in workload but generates
results of greater accuracy. Results gained using each of these two methods were compared in the present study. The results
show that the conventional method generally estimates a meiofaunal biomass. The difference between the two estimation methods
was highly significant (P<0.01) for the spring and winter cruises. Furthermore, the estimation method for meiofaunal biomass affected the analysis
of horizontal distribution and correlation with environmental factors. These findings highlight the importance of estimation
methods for meiofaunal biomass and will hopefully stimulate further investigation and discussion of the topic. 相似文献
27.
Samples of fog water collected in the area of Guangzhou during February, March and April of
2005 are used in this work to study the chemical composition of fog water in polluting fog there. Three
typical episodes of polluting fog are analyzed in terms of ionic concentration and their possible sources. It
is found that the concentration of various ions in fog water is much higher than those in rainwater. Fog not
only blocks visual range but contains liquid particles that result in high degree of pollution and are very
harmful to human health. SO4= is the anion with the highest concentration in fog water, followed by NO3-.For the cation, Ca++ and NH4+ are the highest in concentration. It is then known that rainwater is more
acidic than fog water, indicating that ionic concentration of fog water is much higher than that of rainwater,
but there are much more buffering materials in fog water, like NH4+ and Ca++. There is significant
enrichment of Ca++, SO4=, and Mg++ in fog water. In the Guangzhou area, fog water from polluting fog is
mainly influenced continental environment and human activity. The episodes of serious fog pollution
during the time have immediate relationships with the presence of abundant water vapor and large amount
of polluting aerosol particles. 相似文献
28.
广州地区春季污染雾的化学特征分析 总被引：4，自引：0，他引：4
使用2005年2～3月在广州地区采集的雾水样品资料,分析了广州地区污染雾雾水的化学组分;对3次典型污染雾过程雾水的离子浓度及其可能的来源进行了分析。广州地区的污染雾雾水中的诸离子浓度远高于雨水中的值,因而,雾不但造成视程障碍,而且是高浓度污染的液态颗粒物,对人体健康十分有害。在雾水中浓度最高的阴离子是SO4=, 其次是NO3-;在阳离子中Ca++、NH4+的浓度最高。雨水比雾水更酸,说明虽然雾水中的离子浓度较雨水高得多,但大量的离子成分中存在更多的缓冲物质,比如说NH4+和Ca++。雾水中的Ca++、SO4=、Mg++有明显的富集现象,广州地区的污染雾雾水主要受大陆环境和人类活动的影响。这期间广州地区出现严重污染雾与水汽充足和大量气溶胶污染粒子的存在直接有关。 相似文献
29.
溧阳——介休——五原北西向地震条带,是唐山地震后华北地区地震活动最为活跃的地带。通过研究发生在这条带上强震的震源机制,破裂过程,震源参数及迁移特点,发现这条带上的较强地震具有以下特点: 1.ML5.0级地震的破裂面走向均为北西向,与条带的总体走向基本一致。反映这些地震具有沿破裂面方向迁移的特点。 2.强震是从中间向北西及南东两个条带的延伸方向交替扩展迁移的,并且强度有逐个增大的趋势。而1980年3月9日在条带上平遥地区发生ML=5.7级地震后,再不具备上述迁移,震级增大的特点。 3.截止现在,均以中强震释放能量。其中多数的主压应力P轴与华北地区统一的主压应力方位基本一致,但仍有几个强震与华北地区总体走向明显不同,说明局部条件的影响在这个带上有时可以起主导作用。 相似文献
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