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11.
地震灾情短信编码的初步研究   总被引:1,自引:0,他引:1  
为了充分发挥地震灾情短信的信息负载功能,更全面地获取震后灾情信息,在对现有地震灾情短信代码介绍和分析的基础上,探讨了基于地震灾情现象的短信代码的设计原则和方法。确定了采用线分类法对地震灾情现象进行分类分级,并制定了分类分级的判断标志,然后,根据分类分级结果采用层次编码方式进行了短信代码的编制,设计了应用于不同对象的专业人员代码和公众代码。最后,阐述了如何使用这些地震灾情短信代码进行灾情上报及其对于地震应急工作的意义。  相似文献   
12.
Photo-production of dissolved inorganic carbon (DIC) from chromophoric dissolved organic matter (CDOM) is an important transformation process in marine carbon cycle, but little is known about this process in Chinese coastal systems. This study investigated an estuarine water sample and a coastal seawater sample from the subtropical waters in southeast of China. Water samples were exposed to natural sunlight and the absorption and fluorescence of CDOM as well as the DIC concentration were measured in the summer of 2009. The estuarine water had higher CDOM level, molecular weight and proportion of humic-like fluorescent components than the seawater that exhibited abundant tryptophan-like fluorescent component. After a 3-day irradiation, the CDOM level decreased by 45% in the estuarine water and 20% in the seawater, accompanied with a decrease in the molecular weight and aromaticity of DOM which was inferred from an increase in the absorption spectral slope parameter. The photo-degradation rates of all the five fluorescent components were also notable, in particular two humic-like components (C4 and C5) were removed by 78% and 69% in the estuarine water and by 69% and 56% in the seawater. The estuarine water had a higher photo-production rate of DIC than the seawater (4.4 vs. 2.5 μupmol/(L.day)), in part due to its higher CDOM abundance. The differences in CDOM compositions between the two types of waters might be responsible for the higher susceptibility of the estuarine water to photo-degradation and hence could also affect the photo-production process of DIC.  相似文献   
13.
本文选取金华、衢州、温州、丽水、宁波、杭州六个城市开展PM2.5手工重量法监测,通过比较不同城市不同季节PM2.5质量浓度,研究浙江省PM2.5浓度的分布特征,以期为其空气质量预报、大气污染治理防治等工作提供技术支持。  相似文献   
14.
由于长期超采地下水,导致滹沱河冲洪积平原地下水位持续下降,水质恶化,为缓解滹沱河超采区水资源矛盾,2018年开始实施了河道回补工程,回补水源为黄壁庄水库水和“南水北调”水.为了研究回补后地下水化学效应变化,应用水文地球化学、水文学和统计学等理论方法,开展了现场动态监测、地下水化学检测工作.结果表明:①实施滹沱河补水后地下水位上升显著,滹沱河沿线地下水位平均回升5.83 m;2019年较2015年滹沱河超采区地下水位平均回升5.93 m,地下水漏斗形状发生改变,地下水向漏斗中心汇集已不明显.②滹沱河多年受上游高硫酸盐水源补给的影响,滹沱河沿岸分布HCO3·SO4-Ca·Mg型地下水,并在HCO3·SO4-Ca·Mg型水两侧形成了条带状的HCO3·SO4·Cl-Ca·Mg型水.与2015年相比,2019年HCO3-Ca·Mg型水的面积减少了20.6%,HCO3·SO4·Cl-Ca·Mg型水和HCO3·SO4-Ca·Mg型水的面积增加了13.6%.③河道补给有效缓解了地下水环境恶化,区域地下水中硫酸盐平均含量基本持平,氯化物浓度、TDS(溶解性总固体)浓度、总硬度呈下降趋势;受上游黄壁庄水库补水影响,滹沱河沿岸附近地下水中硫酸盐的浓度升高,高浓度的硫酸盐主要分布在滹沱河、石津灌渠及黄壁庄水库副坝附近,随着补水的不断推进,水位持续回升,在水动力作用下,其有向下游扩散的趋势.研究显示,科学合理地选择补水水源与回补方式是减缓该地区地下水硫酸盐污染及保持地下水可持续利用的有效方式.   相似文献   
15.
厚层橡胶支座稳定的竖向性能有利于实现竖向隔震(振),为量化材性及尺寸变异性对厚层铅芯橡胶支座(TLRB)竖向性能的影响,设计了基于概率密度演化理论(PDEM)的分析框架。建立数值模型并试验验证,以三类平面尺寸的支座为对象,考虑第一形状系数(S1)、第二形状系数(S2)影响,采用GF 偏差选点策略进行竖向刚度的敏感性分析,结合我国现行规范的误差规定,基于PDEM 开展不确定性分析。结果表明:S1是影响竖向性能敏感性的关键因素,而S2的影响可忽略,基于敏感性结果提出了支座生产质量控制的关键参数;S1是影响竖向性能不确定性的关键因素,支座非线性压缩过程会加剧竖向性能的不确定性,基于不确定性分析结果拟合了参数变异性与竖向刚度置信区间的定量经验关系;支座平面尺寸效应对敏感性及不确定性分析结果的影响较小。研究结论可为TLRB的加工制造过程与竖向隔震(振)可靠性评估提供参考。  相似文献   
16.
选取金华、衢州、温州、丽水、宁波、杭州6个城市开展PM2.5手工标准方法和自动监测法比对实验,并用相关性和相对偏差两个指标对比对结果进行分析和评价。结果表明:(1)2013年6个采样城市采集的PM2.5手工和自动监测值均具有较好的相关性(相关系数均在0.95以上),截距均在-0.010~0.010mg/m3,但斜率相差较大(衢州和丽水在0.90以上;金华、温州和杭州在0.85~0.90;宁波在0.80以下)。(2)2013年6个城市采集的PM2.5手工和自动监测值的相对偏差为-34.2%~36.5%;PM2.5手工和自动监测值相对偏差在±15%范围内的数据占总数据量的82.6%;负偏差数据占总数据量的80.0%。(3)PM2.5手工标准方法和自动监测法的比对差异与地域、季节和PM2.5浓度等条件有关。总体上,不同地区PM2.5手工与自动监测值相对偏差绝对值(︱RD︱)年平均值为衢州丽水金华宁波温州杭州;春季PM2.5手工与自动监测值︱RD︱平均值高于夏季,秋季高于冬季;各采样城市PM2.5手工和自动监测值︱RD︱平均值在高质量浓度(PM2.5手工监测值(ρ1)0.150mg/m3)下最小,中质量浓度(0.050≤ρ1≤0.150mg/m3)下最大,低质量浓度(ρ10.050mg/m3)下介于两者之间。  相似文献   
17.
针对现有空气质量预报系统存在预报精度低、人工经验辅助、适用范围单一等问题,利用深度学习方法在分析数据内在特征方面表现出的优异性能,结合多源数据融合技术,设计了基于深度学习的空气质量预报系统实现方案.通过对多源数据集的实时制作更新、分析空气质量演变的时空特性、定义和拟合深度学习模型并部署于服务器等关键技术的研究,最终实现...  相似文献   
18.
A plasmid transfer-mediated bioaugmentation method for the enhancement of dichlorodiphenyltrichloroethane (DDT) degradation in soil was developed using the catabolic plasmid pDOD from Sphingobacterium sp. D-6. The pDOD plasmid could be transferred to soil bacteria, such as members of Cellulomonas, to form DDT degraders and thus accelerate DDT degradation. The transfer efficiency of pDOD was affected by the donor, temperature, moisture, and soil type. Approximately 50.7% of the DDT in the contaminated field was removed 210 days after the application of Escherichia coli TG I (pDOD-gfp). The results suggested that seeding pDOD into soil is an effective bioaugmentation method for enhancing the degradation of DDT.  相似文献   
19.
中国是煤炭消耗的第一大国,同时又是有机废物生物质贮存量第一大国。本文叙述了全球生物质能的历史定位,生物质能的主要评价指标,生物质的能源转换技术和生物质能可供给量模型分析与预测实例,以及我国有机废物类生物质能源化利用途径,并探讨了有机废物的能源利用与废物污染防治相结合的生物质能源发展道路。  相似文献   
20.
The composition of dissolved organic matter (DOM) is an important determinant for its biogeochemical role in the aquatic environments. Therefore, it is crucial to determine the effects of changing land use on the DOM composition in the river watershed. Water samples were collected from the outlets of 15 sub-watersheds in the subtropical Jiulong River (southeast China) for fluorescence measurements and parallel factor analysis. Two humic-like (C1 and C2) and one protein-like (C3) fluorescent components were identified. Overall, DOM in the Jiulong River watershed was dominated by humic-like materials, probably due to the fact that 69% of the watershed is covered with forest. The 15 sub-watersheds were grouped into four clusters based on the proportion of each fluorescent component in the total fluorescence, suggesting that the DOM composition could be very different among sub-watersheds. There was a strong negative correlation between C2 and C3%. C1% correlated with the water body fraction, likely associated with the aquatic production of C1. C3% correlated positively with the residential area fraction, likely indicating the influence of anthropogenic activities. These results are useful for assessing the effects of land use/land cover changes on the composition and hence biogeochemical roles of DOM in aquatic environments.  相似文献   
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