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61.
从FRP加固金属结构设计研究、界面性能研究、工艺研究、耐久性研究等4个方面回顾了FRP加固金属结构技术的发展历程。探讨了FRP加固技术的优势,总结了现阶段FRP修复技术取得的成就和现阶段发展存在的不足。最后,对未来FRP修复技术的发展做了总结。可以预见,随着高性能FRP的不断研制成功以及研究的深入,FRP修复技术必将得到更广泛的应用。  相似文献   
62.
Recently, the New Morris Method has been presented as an effective sensitivity analysis tool for mathematical models. The New Morris Method estimates the sensitivity of an output parameter to a given set of input parameters (first-order effects) and the extent these parameters interact with each other (second-order effects). This method requires the specification of two parameters (runs and resolution) that control the sampling of the output parameter to determine its sensitivity to various inputs. The criteria for these parameters have been set on the analysis of a well-behaved analytical function (see Cropp and Braddock, Reliab. Eng. Syst. Saf. 78:77–83, 2002), which may not be applicable to other physical models that describe complex processes. This paper will investigate the appropriateness of the criteria from (Cropp and Braddock, 2002) and hence the effectiveness of the New Morris Method to determine the sensitivity behaviour of two hydrologic models: the Soil Erosion and Deposition System and Griffith University Representation of Urban Hydrology. In the first case, this paper will separately analyse the sensitivity of an output parameter on a set of input parameters (first- and second-order effects) for each model and discuss the physical meaning of these sensitivities. This will be followed by an investigation into the sampling criteria by exploring the convergence of the sensitivity behaviour for each model as the sampling of the parameter space is increased. By comparing these trends to the convergence behaviour from Cropp and Braddock (2002), we will determine how well the New Morris Method estimates the sensitivity for each model and whether the sampling criteria are appropriate for these models. It will be shown that the New Morris Method can provide additional insight into the functioning of these models, and that, under a different metric, the sensitivity behaviour of these models does converge confirming the sampling criteria set by Cropp and Braddock.  相似文献   
63.
以国家标准分析方法为依据 ,结合企业实际 ,具体阐述了六价铬、铜、镍的半定量分析方法 ,该方法具有测试准、投入少、易掌握、速度快等特点 ,对电镀废水处理设施的调试测定以及企业日常监测管理具有实际指导意义  相似文献   
64.
安徽省淮河流域水污染分析与环境目标可达性探讨   总被引:3,自引:0,他引:3  
介绍了安徽省淮河流域水污染的历史与现状,分析了淮河流域水污染的特点,对实现《淮河流域水污染防治“十五”计划》的可能性进行了探讨。  相似文献   
65.
研制了一种测定水中Mg2 + 的测试管 ,测定范围为 0 .5mg/L~ 2 .0mg/L。该测试管适用于现场应急监测 ,具有快速、简便、抗干扰能力强和价格低廉等特点  相似文献   
66.
本文报道了以7碘8羟基喹啉5磺酸作荧光增强剂的Zn、Al激光时间分辨荧光测定方法。方法检出限分别为25μg/L和10μg/L。用牛肝粉标准品(NBS1577a)进行了验证  相似文献   
67.
The global cycles of man-produced pollutants entering the natural environment are reflected in changes of pollutant cycles, even in background regions.The system of mathematical balance simulation models of inorganic pollutant distribution and circulation (some heavy metals and pesticides included in the priority list for integrated background monitoring) has been developed for the Lake Baikal drainage basin. The system consists of the following units: (1) inventory and classification of regional sources of pollutants entering the atmosphere, natural waters and soils; (2) computation of the global atmospheric transfer and depositions; (3) regional spreading with atmospheric fluxes and deposition onto the underlying surfaces; (4) transport with waterflows feeding Lake Baikal; (5) transport with the lake currents and balance in the lake.The models developed have enabled improvement of existing programmes and systems of observations, in particular to substantiate the large-scale snow sampling and analysis network, and to develop the programme of integrated surveys of the state of Lake Baikal. Since 1981 these actions have been included in the operational network observations within the Lake Baikal Monitoring System.  相似文献   
68.
近年来宁夏对沙尘天气的监测及对沙漠化防治对策   总被引:1,自引:0,他引:1  
宁夏在全区范围内建立沙尘暴监测网络,开展对沙尘天气的应急监测。宁夏作为沙源区和沙尘过往的主要通道,2002年全区共监测沙尘天气12次,沙尘粒径多分布在大于2 1μm。为防治沙漠化,宁夏积极寻求国际间合作,采取退耕还林还草、划管封育、禁牧、把握人工降雨时机等一系列措施,加大对沙漠化的防治力度。  相似文献   
69.
GC- M S法测定蔬菜和水果中八氯二丙醚   总被引:4,自引:0,他引:4       下载免费PDF全文
建立了固相萃取-GC-MS法测定蔬菜和水果中八氯二丙醚残留的方法,样品采用乙腈均质提取,固相萃取柱净化,正己烷定容.优化了试验条件,选择了定性与定量离子,方法线性良好,最低检出限为0.004 7 mg/kg,加标量为0.10 mg/L~1.00 mg/L时,回收率为87.0%~96.0%,RSD<4.0%.  相似文献   
70.
A novel approach to the problem of estimating climate impact on social systems is suggested. This approach is based on a risk concept, where the notion of critical events is introduced and the probability of such events is estimated. The estimation considers both the inherent stochasticity of climatic processes and the artificial stochasticity of climate predictions due to scientific uncertainties. The method is worked out in some detail for the regional problem of crop production and the risks associated with global climate change, and illustrated by a case study (Kursk region of the FSU). In order to get local climatic characteristics (weather), a so-called statistical weather generator is used. One interesting finding is that the 3% risk level remains constant up to 1.0–1.1°C rise of mean seasonal temperature, if the variance does not change. On the other hand, the risk grows rapidly with increasing variance (even if the mean temperature rises very slowly). The risk approach is able to separate two problems: (i) assessment of global change impact, and (ii) decision making. The main task for the scientific community is to provide the politicians with different options; the choice of admissible (from the social point of view) critical events and the corresponding risk levels is the business of decision makers.  相似文献   
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