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91.
为了解重庆市九龙坡区城区和城郊大气污染物浓度特征,分析了城区和城郊国控空气站点2014年3月~2015年2月典型污染物的浓度变化。结果表明,除O_3表现出夏高冬低的季节变化趋势外,其它污染物均表现出冬高夏低的季节变化趋势。PM_(2.5)污染最严重,城区和郊区日均值超标率分别为31.4%和33.4%。城区和城郊的PM_(2.5)浓度之间没有显著性差异(p0.05),城郊O_3浓度显著高于城区(p0.01),NO_2、SO_2、CO和PM_(10)则是城区显著高于城郊(p0.01)。  相似文献   
92.
小流域综合治理新设计研究——猪沼果模式   总被引:3,自引:0,他引:3  
近年来,小流域综合治理的主旨思想改变了,其工作重心在于巩固和发展治理开发的成果,提升综合治理的科技含量,增加治理带来的经济效益。于是将小流域的治理与生产联系起来成为了当前科研人员的研究方向。文章对目前部分地区大力推广的"猪-沼-果"模式在小流域治理方面的概念、发展及综合效益等方面做了一些综述。总的来说,猪沼果模式能够增加农村的能源,增加农民收入,并保护绿植,促进小流域治理。  相似文献   
93.
环境污染易引起大豆种植区域出现过敏原P34蛋白基因变异情况,当前蛋白基因检测方法不能满足检测需求,提出基于探针引物的大豆过敏原P34蛋白基因荧光PCR定量检测技术,针对大豆过敏原特异性基因P34蛋白基因序列进行设计;通过DNA提取、浓度测定,荧光定量PCR检测,实现大豆过敏原P34蛋白基因检测。实验结果表明,所提方法能够准确检测出包括环境污染区域在内的大豆食品过敏原P34蛋白基因成分,具有很好的应用前景,满足市场监督检测的需要。  相似文献   
94.
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   
95.
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   
96.
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   
97.
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   
98.
基于B-P神经网络的环境质量评价方法   总被引:3,自引:0,他引:3  
提出可将环境质量评价的无论是定量指标还是定性参数转化成"二进制"的"1"或"0",进而将这种二进制数引入B-P网络.通过实例探讨,这种新的B-P网络既适用于定量指标的水质参数又适用于定性指标的水质参数.  相似文献   
99.
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   
100.
Although it makes up only a few per cent. of total gaseous mercury (TGM) in the atmosphere, the fraction of oxidised (divalent) mercury plays a major role in the biogeochemical cycle of mercury due to its high affinity for water and surfaces. Quantitative knowledge of this fraction present in mixing ratios in the parts-per-10(15) (ppq) range is currently very scarce. This work is based on approximately 220 data for divalent gaseous mercury (DGM) collected during 1995-99 in ambient air. Over the course of the measurements, the sampling and analytical methods were modified and improved. This is described here in detail and includes transition from wet leaching and reduction procedures to thermo-reductive desorption, the use of annular as well as tubular denuders and adoption of an automated sampling system. The concentration of DGM exhibited a strong seasonal behaviour in contrast to atomic gaseous mercury, with low values in winter and maximum values in summer. The DGM/TGM ratios were frequently found to be below the detection limit (< or = 1%) and in the range 1-5%. A trend of diurnal DGM patterns was observed and implies photolytically induced sources. Scavenging of DGM during rain events was also noticed.  相似文献   
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