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601.
野外调查研究结果表明,安丘-莒县断裂莒县盆地段是一条晚第四纪以来强烈活动的断层.根据断层走向、活动时代及活动性质的变化,可分为两段.董家坡-武家曲坊段和武家曲坊-太湖段,总长度约30km.从滑动速率的分布来看,董家坡-武家曲坊段全新世早期右旋水平滑动速率为1.83mm/a,垂直滑动速率大约为0.37mm/a;全新世晚期右旋水平滑动速率为0.86mm/a,垂直滑动速率大约为0.17mm/a.武家曲坊-太湖段晚更新世早期断裂右旋水平滑动速率为2.78mm/a,垂直滑动速率为0.65mm/a.全新世晚期右旋水平滑动速率为1.37mm/a.垂直滑动速率为0.18mm/a.上述资料表明,安丘~莒县断裂带盆地段的断裂活动无论是时间上还是空间上都有差异,晚更新世以来断裂的活动性有减弱的趋势,全新世时期断裂的活动北段比南段强.  相似文献   
602.
1IntroductionSincethe1970s,theCFCsandHalonsemitedbyhumanhavebeenwidelythoughtassubstanceswhichmaycauseozonedepletioninstrato...  相似文献   
603.
In order to provide further references for studing on the causes of Kaschin-Beck discase (KBD) and measuring for its prevention and treatment from a macroscopic view, we analyzed the natural growth and declineof KBD and the effects of selenium and humic acid on its occurrence from an epidemiologic angle. In this article through a retrospective survey on the spots of disease areas by comparison between a change in water sources and that without. It was proved that a change in water sources was an effective measure for the prevention of KBD occurrence, and the pathogenic factor of KBD was one (or several kinds) of organic compounds or active radicals related to water.  相似文献   
604.
The reaction mechanism of 3-chlorophenol with OH, H in aqueous solution was studied by transient technology.The 3-chlorophenol aqueous solutions have been saturated with air or N2 previously.Under alkaline condition,the reaction of OH radical with 3-chlorophenol produces 3-chlorinated phenoxyl radical ,with the absorption peaks at 400 nm and 417nm.Under neutral condition,the reaction of OH radical with 3-chlorophenol produces OH-adduct with the maximal absorption at about 340 nm.And in acid solution,the reaction of H with 3-chlorophenol produces H-adduct with the maximal absorption at about 320nm.3-chlorophenol is compared with 4-and 2-chlorophenols from the free radical pathways.The results show that the positions of chlorine on the aromatic ring strongly influence the dehalogenation and degradation process.  相似文献   
605.
StudyonthecementitiousnesofasbestostailingsLuZhongyuan,HuoJichuan,LiaoQilong,XiongYimouSouthwestInstituteofTechnology,Mia...  相似文献   
606.
利用氧化铝-改性硅胶联柱分离测定水中多氯联苯   总被引:3,自引:0,他引:3  
储少岗  杨春  徐晓白 《环境化学》1994,13(6):555-560
本文介绍一种多氯联苯(PCBs)与农药的分离和气相色谱分析PCBs新方法.富集浓缩后的样品首先经浓硫酸酸洗.排除大多数干扰PCBs测定的有机化合物,然后利用氧化铝-硅胶(Ag~+)联柱实现了PCBs和干扰其测定的农药的完全分离,应用毛细管气相色谱分析测试了水样中多氯联苯多种同系物、同分异构体的含量.其方法的回收率在79—88%之间.  相似文献   
607.
How and where to improve water quality within an agricultural watershed requires data at a spatial scale that corresponds with individual management decision units on an agricultural operation. This is particularly true in the context of water quality regulations, such as Total Maximum Daily Loads (TMDLs), that identify agriculture as one source of non-point source pollution through larger tributary watershed scale and above and below water quality investigations. We have conducted a systems approach study of 10 coastal dairies and ranches to document fecal coliform concentration and loading to surface waters at the management decision unit scale. Water quality samples were collected on a storm event basis from loading units that included: manure management systems; gutters; storm drains; pastures; and corrals and lots. In addition, in-stream samples were collected above and below the dairy facilities and from a control watershed, managed for light grazing and without a dairy facility or human residence and corresponding septic system. Samples were analyzed for fecal coliform concentration by membrane filtration. Instantaneous discharge was measured for each collected sample. Storm runoff was also calculated using the curve number method (SCS, 1985). Results for a representative dairy as well as the entire 10 dairy data set are presented. Fecal coliform concentrations demonstrate high variability both within and between loading units. Fecal coliform concentrations for pastures range from 206 to 2,288,888 cfu/100 ml and for lots from 1,933 to 166,105,000 cfu/100 ml. Mean concentrations for pastures and lots are 121,298 (SE=62,222) and 3,155,584 (SE=1,902,713) cfu/100 ml, respectively. Fecal coliform load from units of concentrated animals and manure are significantly more than units such as pastures while storm flow amounts were significantly less. Compared with results from earlier tributary scale studies in the watershed, this systems approach has generatedwater quality data that is beneficial for management decisions because of its scale and representation of current management activities. These results are facilitating on-farm changes through the cooperative efforts of dairy managers, regulatory agency staff, and sources of technical and financial assistance.  相似文献   
608.
侯喜福 《干旱环境监测》1992,6(2):114-115,121
就当前建设项目对大气环境影响的环境质量评价中存在的问题,进行了论述,指出五个较突出的问题,以求改进,保证评价报告书的质量.  相似文献   
609.
以顾桥煤矿坚硬顶板综采工作面工程地质条件为背景,运用理论分析、数值模拟和现场实测手段,分析了开采速度对工作面覆岩运动、围岩破坏、应力分布和液压支架承载特性的影响。研究结果表明:1个周期来压内工作面落煤引起的岩梁刚性回转下沉量是一定的,工作面作业循环时间引起的岩梁蠕变下沉量与岩梁刚性回转下沉量呈正比,加快工作面推进速度仅减少围岩体蠕变引起的岩梁下沉部分。工作面开采速度增加,覆岩塑性区发育范围减小,煤壁应力集中位置变浅、应力集中系数变小。工作面快速推进时,液压支架承载多为2次増阻和3次増阻,支架工作阻力较小;缓慢推进时,液压支架承载多为1次急增阻,载荷近似呈线性增长,支架工作阻力较大。  相似文献   
610.
本文介绍了低压离于色谱法测定水样(井水、湖水、矿泉水、自来水)和酸雨中氟、氯、硝酸根、硫酸根离子的方法.欲测阴离子在阴离子交换柱上被分离,同时用1.2mol·l~(-1)N_2CO_3溶液作流动相,流速为 1.6ml·min~(-1).各离子的流分用电导检测.进样量为50μl时F~-,Cl~-,NO_3~-,SO_4~(2-)的最低检出限(2倍噪音比)分别为10,20,250,500ng·ml~(-1).  相似文献   
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