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1.
简要介绍了在水中矿物油的测定过程中,无水硫酸钠铺垫厚度对石油醚萃取液脱水过滤速度及水样测定结果的影响,得出了水样污染越重,石油醚萃取液中含的水份越多,无水硫酸钠铺垫厚度应适当加厚,但测定结果仍满足环境监测要求的结论。  相似文献   

2.
在叶绿素a的测定过程中,萃取时间长短对测定结果产生影响,得出了萃取时间5小时可满足叶绿素a测定要求的结论。  相似文献   

3.
牟文  孙卫平 《四川环境》1997,16(2):18-20
本文对氨电极测定空气中氨的方法进行了研究,确定了最佳分析条件。分析方法的精密度,其平均变异系数为47%;平均回收率为998%,测定结果与纳氏试剂比色法无显著性差异,该方法适用于空气中氨的测定。  相似文献   

4.
对原子荧光光度法测定土壤中总汞含量的不确定度进行了评定。按GB/T22105.1—2008,对土壤样品进行检测,建立数学模型,系统分析和量化不确定度各分量,求得其扩展不确定度。分析结果表明,影响土壤中总汞测定的不确定度主要来源于试样的重复测定,而样品稀释和样品称重产生的不确定度很小。其中,在试样的重复测定所产生的不确定度因素中,又以最小二乘法拟合标准曲线所产生的不确定度最大,样品多次重复测试过程中随机误差次之,而仪器校准和标准物质所产生的不确定度较以上小很多。  相似文献   

5.
程远琼 《四川环境》2003,22(5):28-29
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   

6.
陈英 《四川环境》2023,(5):199-202
为提高土壤中镉含量测定的准确度,采用石墨炉原子吸收分光光度法测定土壤中的镉含量,对整个实验过程进行了不确定度评定。结果表明不确定度主要来源于样品水分测定、样品的制备、绘制工作曲线及样品测定重复性四大过程,工作曲线的绘制引入的不确定度最大,其次为样品的重复性测定,可通过低倍数稀释标准样品、增大标准样品的取样量、设备延长清洗时间、仪器充分预热稳定运行等方式提高实验准确度。研究可为准确评价土壤中镉含量检测结果提供参考,为标准更新提供理论依据。  相似文献   

7.
示波极谱测定空气中甲醛含量的方法及其应用   总被引:6,自引:0,他引:6  
本文研究了用示波极谱测定室内空气中甲醛含量的方法,其结果为:本法测定甲醛的检测下限为34μg/L,加标回收率为875~1100%,变异系数为425~863%,该法灵敏度高,甲醛含量与极谱峰高的线性关系好,是一种可靠的测定室内空气中甲醛含量的方法。同时还研究了缓冲液的pH值及吸收液放置时间对甲醛测定结果的影响,并将该法应用于评价空气净化器去除室内空气中甲醛的效果。  相似文献   

8.
MBR中污泥脱氢酶活性测定方法的改进   总被引:3,自引:0,他引:3  
以MBR中活性污泥为材料,以硫化钠为还原剂,丙酮为萃取剂,对传统TTC-脱氢酶活性测定法进行了改进,解决了标准曲线制作繁琐和稳定性差的缺点,并对测定中诸多影响因素进行了比较分析,确定了最佳实验条件。  相似文献   

9.
大口径毛细管气相色谱法测定大气中的苯系物,采用活性炭吸附,二硫化碳解析,30m×0.53mm×0.88μmHP-1型大口径毛细管分离测定,苯的最低检出限为0.18ng。该方法分离效果好,灵敏度高,是测定大气中苯系物的理想方法。  相似文献   

10.
袁静  张益民  易强 《四川环境》2004,23(4):50-50,53
4-AAP萃取分光光度法测定挥发酚方法中,当挥发酚浓度超出校准曲线范围时,一般将水样稀释后重新分析测定。本文采用氯仿稀释萃取液测定吸光度,通过公式换算求得挥发酚浓度,试验表明,该方法准确可靠,操作简便快捷。  相似文献   

11.
本文提出了应用模糊积分进行大气环境质量综合评价的具体方法和步骤,并用这一方法进行大气环境质量评价,取得了令人满意的结果。该方法的优点是简便实用,评价结果可靠。  相似文献   

12.
This study primarily assesses rainwater supply and demand for Taipei City elementary school to develop a method to derive the rainwater reuse system. This work will help planners build water reuse systems for the sites, and facilitate the water demand of school. This study also analyzes rainfall records from fifteen weather stations in Taipei City to evaluate the rainfall changes in the region's morphology, and measures the rainfall supply in the sub-district of Taipei. The effect of water demand factors is also analyzed with linear regressions applied to estimate the change in monthly water demand for Taipei elementary schools. This work assumes that 35% of total water demand can replaced with rainwater. This work creates an active model for comparisons of each Taipei elementary site rainwater supply trend, demand drift, and maximum rainwater use percentage based on the rainwater reuse system. The efficacy of implementing rainwater reuse in Taipei is identified.  相似文献   

13.
ABSTRACT: Historically, dissolved-oxygen (DO) data have been collected in the same manner as other water-quality constituents, typically at infrequent intervals as a grab sample or an instantaneous meter reading. Recent years have seen an increase in continuous water-quality monitoring with electronic dataloggers. This new technique requires new approaches in the statistical analysis of the continuous record. This paper presents an application of frequency-duration analysis to the continuous DO records of a cold and a warm water stream in rural southwestern Wisconsin. This method offers a quick, concise way to summarize large time-series data bases in an easily interpretable manner. Even though the two streams had similar mean DO concentrations, frequency-duration analyses showed distinct differences in their DO-concentration regime. This type of analysis also may be useful in relating DO concentrations to biological effects and in predicting low DO occurrences.  相似文献   

14.
桑蚕蛹资源及其综合开发前景   总被引:5,自引:0,他引:5  
我国有桑蚕蛹资源50万t/a,干蛹蛋白质高达48.98%.氨基酸种类齐全,8种必需氨基酸占41%。目前大部分蚕蛹仅作为饲料使用,高蛋白资源的浪费极大。蚕蛹可开发20多种保健食品、纺织、轻化工产品.综合开发经济效益高.具有广阔的开发前景。  相似文献   

15.
This paper presents a spatially explicit bioeconomic analysis of species conservation in agricultural areas. Wild species in fragmented agricultural landscapes are best approached as metapopulations consisting of a finite number of local populations. Economic analysis of species conservation in fragmented habitat needs to deal with metapopulation theory and its theoretical implications. This paper presents a spatially explicit bioeconomic model consisting of a straightforward economic land use model and an applied metapopulation model. This paper demonstrates that multiple equilibria and multiple local optima in metapopulations might lead to nonconvexities in the production possibilities set of agricultural profits and species conservation.  相似文献   

16.
Typhoon Morakot triggered flooding and mudslides in various areas and devastated Aboriginal villages located near areas under construction by the Water Diversion Project in Kaohsiung County. This paper examines the controversy surrounding Typhoon Morakot in Taiwan from the perspective of disaster governance. This study provides competing perspectives regarding who was responsible for causing the disaster. Post-disaster reconstruction initiatives by the government tend to adopt a technical approach to risk, and do not incorporate the complex social and cultural dimensions of vulnerability and sustainability. This perspective reflects misrecognition problems, and the lack of empowerment and participation in governance by residents, as well as their exclusion in decision making. Aboriginal civic groups have various methods of interacting with local residents to alleviate the suffering of survivors, promoting tribal culture and building resilient communities. This continuing development of social interactions and new forms of engagement will effectuate transformation and contribute to broader reflections on the Morakot disaster and social capability and building resilience.  相似文献   

17.
This paper explains how the well-accepted concept of improved stakeholder participation during mineral policy development leads to a national mineral policy that accommodates the diverging views and interests that allows wide acceptance of decisions, enhancing the success of implementation and, ultimately, national benefits. This process is based on lessons learnt during the South African experience and has been successfully applied in the development of the Namibian and Malawian national minerals policies. An effective policy in the SADC will engineer the delicate balance between poverty reduction and an internationally competitive minerals sector. This balance enhances the possibility of long-term economic growth and development in the SADC region. The overriding advantage of this strategy is that it generates ‘home-grown’ policy instruments and implementation of mineral law with which stakeholders can identify. This process presents a new challenge to traditional policy formulation strategies in emerging economies and the bottom-up approach, linked to wide political support, allows the potential realisation of national objectives.  相似文献   

18.
对中国环境管理干部学院的动物伦理教育进行了总结,提出动物伦理教育是大学生思想政治教育的一个重要方面的观点,指出动物伦理教育不仅事关动物,而且关系到大学生人格的培养。  相似文献   

19.
上世纪九十年代开始,LIMS系统在我国第三方实验室得到应用.实验室由此改进了管理模式,提高了工作效率,减少了管理成本.但是多方面制约因素使其成熟度和先进性与国外类似系统存在较大差距.本文从LIMS的功能、信号采集、实施全过程质量管理和延伸服务能力四个方面,简要介绍目前国内第三方实验室应用现状和存在的问题,初步分析今后L...  相似文献   

20.
This paper presents potential energy savings by installing high-efficiency motors instead of existing ones and their impact on greenhouse gases emissions reductions. This research study of the energy efficiency of electric motors has been performed in a typical thermal power plant. In the literature, the focus has been mainly on separate and away electric motors from operating facilities. The important advantage of this paper over other studies is that it uses the actual motors’ efficiency in the evaluation. The gains both in terms of electrical energy savings and in terms of financial economy by using high-efficiency motors have been discussed. As a result, the energy saving can be expected as 12.6% at the operating rate. This excellent result also reduces greenhouse gas emission by 1,423 tons every year. The analysis of the data provided an overview on energy losses often generated by the degradation and rewinding of electrical motors. This study represents very encouraging results that will help energy managers of industrial plants to become more involved in energy efficiency strategies.  相似文献   

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