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21.
室内培养底栖端足类日本大螯蜚饵料研究 总被引:1,自引:0,他引:1
本文在实验条件下探讨了5种饵料对海洋底栖端足类日本大螯蜚的培养效果。实验指标为存活率,生长速度,日增长率和发育状况。结果表明,青岛大扁藻与新月菱形藻1:1混合液的培养效果最佳,合成饲料是较好的补充饵料,螺旋藻粉不宜作为日本大螯蜚的培养饵料。动物性饵料培养效果不如植物性饵料,但对日本大螯蜚的早期快速成长具有一定的促进作用。 相似文献
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本文以呼市发电厂废水、粉尘和灰场污染治理为例,研究制定发电厂粉煤灰综合治理与回收利用技术方案、旧灰场的生态工程建设和冲灰水的回收利用方案,通过污染物治理,废水的利用率达到85%,粉煤灰处理后的产草量和年利用率为98%,灰场的植被覆盖度达到97%,通过治理使发电厂的污染物排放量减少,废弃物资源得以利用,灰场变成环境优美的生态旅游区,为我国电厂的治理工作提供一个切实可行的科学依据。 相似文献
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本文对如何正确使用TH-880Ⅲ型微电脑烟尘平行采样仪进行了探讨,提出了实际测试过程中应注意的一些关键问题,以及一些常见故障的排除方法。 相似文献
26.
Tarhule Aondover Woo Ming-ko 《Mitigation and Adaptation Strategies for Global Change》2002,7(3):215-237
Domestic and agro-economic activities in the semi-arid region of Nigeria rely exclusively on rainfall, streamflow and groundwater in deep and alluvial (fadama) aquifers. Such water supply systems are subject to considerable seasonal and inter-annual variability. However, a combination of the various sources may mitigate the effects of water scarcity. This study describes the dynamics of the water sources for a village in northeastern Nigeria as an example that demonstrates the linkages between rainfall, streamflow and groundwater. Such linkages are important for developing strategies to mitigate the effects of climatic variation. Long-term records of rainfall were not available at the site so that the short-term data was interpreted in the context of the long-term climatic experience of the region. The stratigraphic profile of the aquifer was developed from resistivity methods, to supplement information obtained from well level hydrographs. Field observations and analysis of the data reveal that the beginning of the rainy season is a precarious period because none of the water sources are reliable. Rainfall infiltration recharges the shallow aquifers while lateral water flux from the floodwater-saturated fadama also contributes to water level rises in the deep wells. A study of the water level changes in response to deepening of the wells suggests that the wells are fed by an assortment of water-bearing lenses, separated by layers of low transmissivity. One major finding of this study is that there exists a close association between the wells in this riparian community and the recharge processes within the fadama. Upstream diversion, abstraction or impoundment could therefore undermine the viability of aquifer exploitation by the communities in the riparian zone. Analysis of the interactions among the various sources of water leads to the identification of several potential adaptation strategies for confronting the problem of water scarcity. 相似文献
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Edmonds Jae Wise Marshall Pitcher Hugh Richels Richard Wigley Tom MacCracken Chris 《Mitigation and Adaptation Strategies for Global Change》1997,1(4):311-339
We report results from the application of an integrated assessment model, MiniCAM 1.0. The model is employed to explore the full range of climate change implications of the successful development of cost effective, advanced, energy technologies. These technologies are shown to have a profound effect on the future magnitude and rate of anthropogenic climate change. We find that the introduction of assumptions developed by a group of ‘bottom-up’ modelers for the LEESS scenarios into a ‘top-down’ model, the Edmonds-Reilly-Barns Model, leads to ‘top down’ emissions trajectories similar to those of the LEESS. The cumulative effect of advanced energy technologies is to reduce annual emissions from fossil fuel use to levels which stabilize atmospheric concentrations below 550 ppmv. While all energy technologies play roles, the introduction of advanced biomass energy production technology is particularly important. The consideration of all greenhouse related anthropogenic emissions, and in particular sulfur dioxide, is found to be important. We find that the consideration of sulfur dioxide emissions coupled to rapid reductions in carbon dioxide emissions leads to higher global mean temperatures prior to 2050 than in the reference case. This result is due to the short-term cooling impact of sulfate aerosols, which dominates the long-term warming impact of CO2 and CH4 in the years prior to 2050. We also show that damage calculations which use only mean global temperature and income may be underestimating damages by up to a factor of five. Disaggregating income reduces this to a factor of two, still a major error. Finally, the role of the discount rate is shown to be extraordinarily important to technology preference. 相似文献
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介绍了在2个监测点,用直接法测定大气中的非甲烷烃。测定方法的检出限可达0.0065mg/m^3,在线性范围0-10mg/m^3时,线性相关系数为0.9995,相对标准焦虑差为2.8%。结果表明,由于大气逆温层、工业排放源、汽车排气对非甲烷烃的浓度变化产生影响,其日变化曲线呈双峰形。 相似文献
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CharacteristicsofphosphoruschemistryanditsgeographicaldistributionintheHaiheRivervalley,NorthChinaJiangGaoming;HuangYinxiao;L... 相似文献
30.
炼油装置运行周期评估技术通过统计、分析装置故障数据,计算特定时间段装置的可靠性,进而获得装置可靠性随时间的变化规律和装置可靠性最差设备排序。介绍了该技术在某常减压装置的应用,应用结果表明,该评估技术为科学确定炼油装置运行周期提供了决策依据。 相似文献