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211.
煤层瓦斯压力测定中的钻孔注浆新技术研究   总被引:2,自引:1,他引:1  
为简化复杂地质条件下测定煤层瓦斯压力的工序并提高高压注浆的成功率和可靠性,以达到准确、快速测量瓦斯压力的效果,基于胶囊注水封孔器的原理和特性及高压注浆的现场情况,提出了一种新型的注浆方法。通过钻孔注浆模型的建立和数值分析、模拟,发现新式注浆工艺可满足10 MPa的注浆压力,能有效封堵钻孔中的裂隙。现场对比实验证明新式注浆方法较传统注浆方法减少了工序,提高了安全性和可操作性,节省时间约35 h。新型注浆方法在复杂地质条件下可提高测压工作整体的效率。  相似文献   
212.
《Environmental Hazards》2013,12(3):210-223
Traditional knowledge of disasters has been found to save lives. On remote islands where telecommunications to the mainland are unreliable, unless there are always working batteries in the radio, signs from the environment may be the only warning of an oncoming cyclone. But this knowledge is in danger of being lost, as it is an oral history not well documented, and younger people increasingly rely on technology. This article presents the results of fieldwork on remote islands in Fiji and Tonga in the South Pacific, documenting natural warning signs on islands in two different countries. The results show that there are numerous known signs, with remarkable similarities and consistencies between the two islands. This provides evidence that not only is traditional knowledge of warning signs for cyclones alive and well, the consistency in the signs suggests support for this knowledge as being just as important as western scientific knowledge. The integration of traditional knowledge and western scientific knowledge into a comprehensive warning system may help to overcome some of the limitations of the existing system and the reasons why warnings are sometimes ignored.  相似文献   
213.
王有清 《交通环保》2001,22(5):29-30
简述了中国城市生活污水和港口除尘水源的概况。分析了港口开发利用城市生活污除尘的一些相关标准和技术问题。提出了应用化学助剂处理城市生活污水的技术路线。  相似文献   
214.
The steadily increasing world market prices for fossil fuels in the past years have significantly increased interest in the development of indigenous sources of energy in the Pacific islands. As an import substitution strategy, many Pacific island Governments are looking into the use of local biomass resources to replace traditionally imported fuels such as petrol and diesel by biofuels. An overview of biofuel activities is given, with experiences and key achievements in Fiji, Samoa, Vanuatu, Solomon Islands, Papua New Guinea, Kiribati and Marshall Islands with regard to efforts to develop alternative fuels. There are strong linkages between developments in the various Pacific island countries and lessons to be learned from experiences and policies implemented among Governments in the Pacific region. The paper concludes that there is a need for standardization, quality control and testing facilities for biofuels in the region. Governments need to investigate further the level of support that is required to make biofuel operations viable and maximize macroeconomic and environmental benefits.  相似文献   
215.
目的研究AHБ,CuAl/NiC和NiCrAl/NiC三种可磨耗涂层的抗腐蚀性能。方法对三种涂层试样进行盐雾试验、湿热试验和浸泡试验,并结合电化学测试分析不同涂层试样的抗腐蚀性能。结果 545 h的盐雾试验后,AHБ涂层的表面出现了一处微裂纹,CuAl/NiC涂层表明出现了涂层剥落现象,NiCrAl/NiC涂层的表面状况相对最好;三种涂层试样经过10个循环的湿热试验后均未见明显的腐蚀现象;经过15 d的浸泡试验后,NiCrAl/NiC涂层的表面状况相对较好,而AHБ涂层和CuAl/NiC涂层的表面状况相对较差;电化学测试结果也表明NiCrAl/NiC涂层的防护性能相对最好。结论 NiCrAl/NiC涂层的抗腐蚀性能相对较高,而AHБ涂层和CuAl/NiC涂层的抗腐蚀性能相对较低。  相似文献   
216.
An intensive and persistent regional ozone pollution event occurred over eastern China from 25 June to 5 July 2017.73 out of 96 selected cities,most located in the Beijing-TianjinHebei and the surrounding area(BTHS),suffered severe ozone pollution.A north-south contrast ozone distribution,with higher ozone(199±33 μg/m~3) in the BTHS and lower ozone(118±25 μg/m~3) in the Yangtze River Delta(YRD),was found to be dominated by the position of the West Pacific Subtropical High(WPSH) and mid-high latitude wave activities.In the BTHS,the positive anomalies of geopotential height at 500 hPa and temperature at the surface indicated favorable meteorological conditions for local ozone formation.Prevailing northwesterly winds in the mid-high troposphere and warm advection induced by weak southerly winds in the low troposphere resulted in low-moderate relative humidity(RH),less total cloud cover(TGC),strong solar radiation and high temperatures.Moreover,southerly winds prevailing over the BTHS aggravated the pollution due to regional transportation of O_3 and its precursors.On one hand,the deep sinking motion and inversion layer suppressed the dispersion of pollutants.On the other hand,O_3-rich air in the upper layer was maintained at night due to temperature inversion,which facilitated O_3 vertical transport to the surface in the next-day morning due to elevated convection.Generally,temperature,UV radiation,and RH showed good correlations with O_3 in the BTHS,with rates of 8.51(μg/m~3)/℃(within the temperature range of 20-38℃),59.54(μg/m~3)/(MJ/m~2)and-1.93 μg/m~3)/%,respectively.  相似文献   
217.
利用1995~2001年7~11月表温数据和生产统计数据,采用GIS软件Marine Explorer 4.0和统计软件SPSS 11.0分析了东太平洋金枪鱼延绳钓大眼金枪鱼钓获率与海水表温之间的关系.结果显示:7月份,81.55%的钓获率分布在表温21~27 ℃范围内;8月份,93.08%的钓获率分布在表温19~28 ℃;9月份,93.06%的钓获率分布在表温18~28 ℃;10月份,76.79%钓获率分布在表温21~27℃;11月份,88.89%钓获率分布在表温21~28 ℃.同时,利用K-S检验可知,以上分析出来的海水表温(SST)范围基本上可以作为各月份形成渔场的适宜指标之一.  相似文献   
218.
太平洋上空硫酸盐的分布和来源   总被引:3,自引:2,他引:3  
我国首次南极考察(1984年11月—1985年3月)在太平洋和南极半岛周围海域收集了31个海洋气溶胶样品。采用离子色谱法分析气溶胶中硫酸盐、火焰原子吸收法分析钠离子,结果表明,太平洋海洋气溶胶中非海盐源硫酸盐含量自北纬向南纬明显降低。在北太平洋主要是由于陆源污染源的硫酸盐在风系作用下经长距离传输而进入海洋上空;而在南太平洋,特别是南极半岛海域大气中非海盐源硫酸盐,可能主要来自海洋生物活动的产物。利用通量计算模式,估算了南极半岛海域生物源输入大气的硫通量为0.065gS/m~2·a。  相似文献   
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