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1.
测定环境空气中微量氟的方法一般采用滤膜法,但此法工作量大,针对这种情况,本文作两点改进:一是将采集的两张滤膜同时测定;二是将测定过程中的搅拌时间缩短,这样不影响测定结果的准确性,而且降低了工作量。 相似文献
2.
针对四川石油天然气工业环境统计中存在的非稳定污染源监测数据的统计价值不高,统计调查方法单一,个别统计指标计算未使用国家统一标准等现状,从环境监测站改组入手,改革统计调查方法,建立以必要的周期性普查为基础,以经常性的抽样调查为主体,同时辅之以全面统计报表,重点调查和科学推算综合运用的统计调查方法体系。 相似文献
3.
4.
本文介绍采用德国进口的LB9100D监测系统对80m烟囟排放的α放射性气溶胶浓度进行连续、自动监测。并与国产FJ-367,FH-463A装置进行了对比则量,两套装置的测量结果符合得较好。 相似文献
5.
气象卫星遥感在干旱监测中的应用 总被引:23,自引:1,他引:23
本文根据NOAA极轨气象卫星AVHRR资料计算生成植被指数相对距平图用于旱情监测,并在江苏省1994年特大干旱中进行了应用服务 相似文献
6.
基于C/S与B/S混合模式的大气污染监测系统设计 总被引:1,自引:0,他引:1
以C/S与B/S混合模式为基础的大气监测系统、既能充分发挥网络资源的便捷化,实现企业监测数据与管理系统的快速链接,又充分利用C/S模式的安全性能,以保证系统的安全性。因而此系统是当前的一种较新型的,功能较为强大的网络监测系统。 相似文献
7.
A data analysis of three major Korean cities was conducted to assess roadside inhalable particulate matter 10 μm or smaller
in aerodynamic diameter (PM10), including temporal and meteorological variations, over a recent period of 4 to 6 years. The yearly roadside PM10 concentrations presented a well-defined increasing trend or no trend depending on the roadside monitoring station. Most mean
values exceeded or approximated the Korean standard of 70 μg/m3 per year for PM10. A representative roadside diurnal trend was characterized by a distinct morning maximum. In most cases, the Sunday roadside
concentrations were similar to or somewhat lower than the weekday concentrations, and the PM10 concentrations presented a well-defined seasonal variation, with the maximum concentration in March. The monthly maximum
concentrations observed in March were most likely attributable to Asian dust storms. In two metropolitan cities (Seoul and
Busan), the frequency of days with roadside PM10 concentrations exceeding the standard of 150μg/m3 per 24 h was much lower for the roadside monitoring stations than for the residential monitoring station, whereas in the
third city (Daegu), this result was reversed. Interestingly, the average maximum concentrations observed for the roadside
sites in Seoul and Busan during March were higher than those for the residential sites, suggesting that the roadside concentrations
responded more to the dust storms than the residential areas. The relationship between the pollutant concentrations and five
important meteorological parameters (solar radiation, wind speed, air temperature, relative humidity, and precipitation) showed
that the number and type of meteorological variables included in the equations varied according to the monitoring station
or season. Finally, the current results confirmed that attention should be given to the PM10 exposure of residents living near roadways. 相似文献
8.
DENNIS D. COX LAWRENCE H. COX KATHERINE B. ENSOR 《Environmental and Ecological Statistics》1997,4(3):219-233
In this paper we summarize research issues for spatial environmental sampling stemming from a NISS/USEPA workshop held on 21-22 September 1994 at Chapel Hill, NC. 相似文献
9.
10.
Comprehensive temperature monitoring in an in-vessel forced-aeration static-bed composting process 总被引:6,自引:0,他引:6
Masafumi Tateda Le Duc Trung Nguyen Viet Hung Michihiko Ike Masanori Fujita 《Journal of Material Cycles and Waste Management》2002,4(1):62-69
Comprehensive temperature monitoring was done in an in-vessel forced-aeration static-bed composting process using sewage sludge.
The three layers that divided the compost pile horizontally showed different temperature distributions. The temperature of
the top layer appeared not to be influenced by the ambient temperature. The temperature of the center area of the top layer
was taken to be the representative temperature for evaluating composting start-up performance. The temperature of the bottom
layer was strongly influenced by the ambient temperature, and the temperature of the center area of the bottom layer was taken
to be the representative temperature for pathogen control as it was the minimum temperature in the reactor. Composting start-up
performance was influenced by several factors when the ambient temperature was either below or above 20°C. When the ambient
temperature was below 20°C, the time taken to reach 65°C (T
65) was influenced by the temperature of inflowing air, but when the temperature was higher than 20°C, it was influenced by
the ratio of sewage sludge to seed compost (F/S). T
65 was least when F/S was 1–2.
Received: January 9, 2001 / Accepted: October 10, 2001 相似文献