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排序方式: 共有1046条查询结果,搜索用时 78 毫秒
941.
利用计算机技术编制多媒体环境质量报告书 总被引:1,自引:0,他引:1
利用计算机技术编制多媒体声像环境质量报告书,具有三维图像、全程多媒体自动播放坐标图动态显示、生动活泼、声图并貌的特点。 相似文献
942.
Six air issues are currently on science and policy agendas in Canadaand elsewhere. These are climate change, stratospheric ozone depletion(increased UV-B radiation), acidic deposition, SMOG (increasedground-level ozone), suspended particulate matter, and hazardous airpollutants. Atmospheric scientists and decision makers have largelyaddressed these issues individually resulting in single-issue policies. However, it is now recognized that these issues are inter-related, andthey may interact to cause negative as well as some beneficial effects,not only on the state of the atmosphere but also on societal andecological systems. This paper illustrates through several examples theatmospheric dysfunction caused by the linkages among the six airissues. It also points to potentially conflicting policies arising from thesingle-issue approach, and it emphasizes the need for better integrationof air issues. The linkages are summarized qualitatively in Table I. 相似文献
943.
利用遥感数据处理软件SNAP中基于神经网络技术的C2RCC算法,对2019年5月9日南黄海“哨兵3号”卫星OLCI影像数据进行了叶绿素a及总悬浮物浓度反演,将其与5月间江苏省海洋环境监测预报中心的海水表层叶绿素a和悬浮物实测数据进行了比较分析。结果表明,叶绿素a的遥感反演尚未能达到业务化应用,总悬浮物遥感反演结果的空间分布与实测值的一致性相对较好。但在星地同日或相差一天监测的南通海域,遥感反演叶绿素a浓度的空间分布趋势以及总悬浮物遥感反演结果与海面实测结果的一致性较好,可达到一定的业务化应用效果。 相似文献
944.
In a field study 78 water samples were analysed employingFluorocult Brilla Broth (BB) and its performance was comparedwith standard MPN procedure. Out of 78 water samples analysed 56(71.7%) samples yielded positive reactions in BB whereas, 50(64.1%) samples were positive by standard fecal coliform test.A comparative study of fluorogenic and chromogenic mediacontaining substrate -D glucuronide for specificdetection of environmental isolates of 313 thermotolerant E.coli has been undertaken. Five fluorogenic media wereused: Fluorocult MacConkey agar (MCA), Fluorocult ECD agar(ECD), Fluorocult VRB agar (VRB), Fluorocult E. coli0157:H7 agar (ECH7) and Fluorocult Brilla Broth (BB) andChromogenic Chromocult agar (CCA). BB and CCA were found to behighly specific and sensitive media to detect E. coli asall E. coli yielded positive reaction on them. On ECH7 andECD agar 67.5 and 64.9 of E. coli isolates gave positivereaction, respectively. Low sensitivity was observed in case ofMCA and VRB agar in detecting E. coli. The performance ofBB appears to be better when compared with standard MPNprocedure employing MacConkey broth/Brilliant green bile brothin detecting E. coli in drinking water. 相似文献
945.
影响悬浮物测定的因素主要有:样品采集、取样量及测定条件。悬浮物样品采集要注意采样位置和采样深度应合理设定;应单独定容采样,并全部用于分析测试,测定悬浮物的取样量最佳含量为10-100mg;选择适合的滤料与过滤洗涤,以及烘干温度与时间、称量。 相似文献
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948.
移动床生物膜工艺特点、研究现状及发展 总被引:27,自引:0,他引:27
悬浮载体生物膜工艺(MBBR)又称悬浮填料移动工艺,是在20世纪90年代中期得到开发和应用的,它吸收了传统的活性污泥法和生物膜法两者的优点而成为一种高效的污水处理方法。在国外,悬浮载体移动膜工艺已进入使用阶段。我国在悬浮载体移动膜工艺上基本还处于研究阶段。对这一工艺的特点、研究现状及方向作了介绍。 相似文献
949.
Feng Peng David L. Johnson Steven W. Effler 《Journal of the American Water Resources Association》2002,38(5):1453-1465
ABSTRACT: The technique of i ndividual p article a nalysis conducted by s canning electron microscopy interfaced with a utomated X ‐ray microanalysis (IPA/SAX) was used to characterize suspended particulate matter in New York City's drinking water reservoirs and their tributaries. The study covered a two year period and involved analyses of more than 300 samples. The particle cross sectional area per unit volume (PAV), or area concentration, was measured to account for the observed turbidity, a representation of light scattering property of the studied medium. A simple linear model with a nearly zero intercept was able to explain more than 85 percent of the variation in the measured turbidity. Moreover, the particle assemblage was categorized into generic particle types with distinctive geochemical or geological origins. Thus, PAV compositions in terms of particle types could be apportioned into turbidity components based on the model. Inorganic tripton, dominated by aluminosilicate (clay) and silicate of nonbiological nature, was found to be the major turbidity causing constituent in most cases. With the exception of one reservoir where organic detritus was significant, the predicted inorganic particle turbidity agreed with the measured turbidity within experimental error. 相似文献
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