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1.
理论研究是做好实验的基础。只有从理论给予说明,才能充分发挥主观能动作用,以有效地排除实验中的异常现象,从而获得理想的实验结果。本文从实验方法、操作技巧等方面剖析了砷测定方法的机理。  相似文献   

2.
分析了地表水中总磷监测过程中的质量控制方法,着重讨论了空白实验,检测限的计算校准曲线的回归与检验,标准品的测定,空白实验的质量控制图等。  相似文献   

3.
空气中二氧化硫的测定对实验室测定条件比较敏感。通过实验表明显色时间、显色温度、PRA纯度、蒸馏水质量等实验条件均对其校准曲线的斜率和空白值有影响,所以在实验分析过程中,必须严格把握操作条件,严格遵循操作步骤。  相似文献   

4.
实验室里几种废弃物的危害及处理   总被引:6,自引:0,他引:6  
本文就实验室废弃物收集,以及氰化物,汞,砷,苯等污染物对实验人员的危害和实验室如何处理这些废弃物作了论述,对维护实验人员健康,防止环境污染有积极意义。  相似文献   

5.
用改进的凯氏法测定生物样品和水样中总氮方法的探讨   总被引:3,自引:0,他引:3  
对凯氏法测定生物环境样品中总氮的测定方法进行了研究和改进,以简易装置代替凯氏消解装置,省略了蒸馏步骤。避免了称量时易造成的样品损失及蒸馏过程的氨氮损失。经过实际样品的测定,并与原测定方法进行了对比实验,证明改进后的测定方法具有准确度高,精密度好,实验装置及步骤简便易行的特点。缩短了实验周期,提高了氮的回收率。同时,用改进后的方法对水样进行了测定,也取得了良好效果。  相似文献   

6.
本文对挥发酚实验用水进行探索及改进.直接采用蒸馏水代替无酚水为实验用水。应用于质控考核工作中,取得较理想的显著效果。结果表明.精密度、准确度都符合分析要求,并能降低成本,省时、省电、提高工效,可广泛应用于环境监测工作中,具有普遍实用价值。  相似文献   

7.
正交实验能在多因素下分清各因素在实验中的主次作用并找出较好的运行方案.它运用数学上的方差分析,简便而科学,具有普遍的意义.本文用正交实验对挥发酚测定中影响空白值大小因素进行简单处理,供从事水质分析的同仁参考,对水环境监测的实际工作也有一定的指导意义.  相似文献   

8.
研究了用无水乙醇代替N-N二甲基甲酰胺,比较了2种试剂对测定的影响,并就实验条件对测定的影响作了进一步分析,提出了此法的最佳实验条件。  相似文献   

9.
紫外分光光度法测定水中总氮影响条件的实验研究   总被引:1,自引:0,他引:1  
碱性过硫酸钾氧化-紫外分光光度法测定水中总氮时,实验的准确性受到很多条件的影响。本文分别从试剂的选择、试剂的配制、消解的温度与时间、实验用水、比色管的选用及清洁度等方面进行研究,从而保证实验的准确性与可靠性。  相似文献   

10.
双硫腙比色法测定锌实验条件的改进祁成华,郑新秀,严香文(新疆昌吉州环境监测站831100)双硫腙比色法测定锌适用于测定天然水和轻度污染的地表水,但该法易受实验室环境的干扰,空白试验值高.曲线的相关性较差。通过对实验条件的改进.大幅度降低空白测定值,提...  相似文献   

11.
介绍了用 GC/MS仪对水中微量有机污染物进行分离定性、定量的实验方法 ,并通过对实验结果的分析 ,阐述了高锰酸盐复合药剂 (PPC)对巢湖水中有机污染物的去除效率。文中表明 :GC/MS方法可检测的有机物范围很宽 ,它适用于可被 C18小柱从水中有效吸附 ,对气相色谱有足够的热稳定性和挥发性的有机化合物的分析。同时 ,由实验结果得到 :高锰酸盐复合药剂对巢湖水中有机污染物有较好的去除效果。  相似文献   

12.
13.
A sensitive and accurate analytical method based on dispersive liquid-liquid microextraction was developed for the simultaneous determination of selected pesticides, hormones, and endocrine disruptors by GC-MS. The optimum conditions of the extraction procedure were determined using an experimental design of factors significantly affecting the extraction output. Analysis of variance (ANOVA) was used to evaluate the main effects of experimental factors and their interactions. The limit of detection values determined for the analytes under optimum experimental conditions were found to be between 0.30–2.0 ng/mL. The linear calibration plot of analytes span across a wide concentration range and low %RSD values from replicate measurements indicated good precision of the developed method. Spiked recovery tests were also performed on municipal wastewater, well water, lake water, sea water, and tap water matrices to determine the method’s accuracy and applicability to water samples. The recovery results obtained were satisfactory for all water samples.  相似文献   

14.
凤眼莲死亡对湖泊水质的持续性影响分析   总被引:12,自引:0,他引:12  
凤眼莲是优良的污水净化植物,凤眼莲死亡后残体对水质的影响制约了其应用.在凤眼莲衰亡后,调查研究凤眼莲死亡对自然水体水质的影响,结果表明,在凤眼莲的衰亡期,其对富营养化水体的透明度、CODMn、TN、TP、NH4 -N等指标仍然具有改善作用;在后续影响期(次年春季),在有凤眼莲死亡腐烂的水体中,除了水体TN浓度呈现增加趋势外,其他主要水质指标的浓度变化均不明显.  相似文献   

15.
洪湖水质空间特异性及主导因子分析   总被引:8,自引:6,他引:2  
运用聚类分析和主成分分析方法对洪湖湿地12个采样点的理化特性进行分析。聚类分析表明,根据各采样点水质组分的相似性将洪湖大致分为3个空间区域,各空间区域正好分属于核心区、实验区、河口区,各区域间特征差异显著。对各区域水质的主成分分析表明,洪湖不同空间区域水质信息差异很大。第1组核心区主要体现富营养化信息;第2组实验区主要体现总氮、氧化还原电位、浊度信息;第3组河口区主要体现溶解氧及亚硝酸盐氮等污染物信息。揭示了洪湖水质现状及其成因,为洪湖水资源合理利用及生态保护提供基础数据。同时,运用地统计学方法为生态环境研究提供新的思路与方法。  相似文献   

16.
Occurrence of halogenated disinfection by-products (DBPs) (trihalomethanes –THMs– and haloacetic acids –HAAs–) in the waters of two utilities in Quebec City (Canada) was investigated using two approaches: experimental chlorination studies and full-scale sampling within distribution systems. Experimental studies were designed to reproduce treatment plant and distribution system conditions (chlorine dose, water temperature, pH and water residence time). Differences in halogenated DBPs in the two distribution systems under study were significant and comparable to those observed in experimental laboratory studies. For the waters of both utilities, chlorination studies better reproduced the occurrence of halogenated DBPs in points of the distribution system located near the treatment plant (low residence time of water) than in other points. Multivariate regression models for THMs, HAAs and their species were developed using the data from experimental studies in order to predict halogenated DBP levels measured in the distribution system. Models were all statistically significant, but showed low ability to predict full-scale halogenated DBPs, particularly in points located at distribution system extremities. Specifically, experimental chlorination-based models are not able to simulate the decrease of HAA levels. Results of this research suggest that the use of experimental data to predict halogenated DBP levels in full-scale distribution systems – for operational, regulatory and epidemiological purposes – must be done with caution.  相似文献   

17.
叙述了用荧光光谱法鉴别污油油种的实验条件和方法,根据可疑船舶舱底水污油和江面溢油的“油指纹”荧光光谱图,提供确定排污油船只的依据。  相似文献   

18.
19.
An immense volume of tailings and tailings water is accumulating in tailings ponds located on mine leases in the oil sands area of Alberta, Canada. Oil sands mining companies have proposed to use tailings- and tailings water-amended lakes and wetlands as part of their mine remediation plans. Polycyclic aromatic hydrocarbons (PAHs) are substances of concern in oil sands tailings and tailings water. In this study, we determined concentrations of PAHs in sediments, insect larvae and adult insects collected in or adjacent to three groups of wetlands: experimental wetlands to which tailings or tailings water had been purposely added, oil sands wetlands that were located on the mine leases but which had not been experimentally manipulated and reference wetlands located near the mine leases. Alkylated PAHs dominated the PAH profile in all types of samples in the three categories of wetlands. Median and maximum PAH concentrations, especially alkylated PAH concentrations, tended to be higher in sediments and insect larvae in experimental wetlands than in the other types of wetlands. Such was not the case for adult insects, which contained higher than expected levels of PAHs in the three types of ponds. Overlap in PAH concentrations in larvae among pond types suggests that any increase in PAH levels resulting from the addition of tailings and tailings water to wetlands would be modest. Biota-sediment accumulation factors were higher for alkylated PAHs than for their parent counterparts and were lower in experimental wetlands than in oil sands and reference wetlands. Research is needed to examine factors that affect the bioavailability of PAHs in oil sands tailings- or tailings water-amended wetlands.  相似文献   

20.
水中硫化氢的溶解规律   总被引:2,自引:0,他引:2  
对气体在水中的溶解机制进行了分析,并结合实验数据导出了硫化氢在水中溶解度的预测公式,该预测公式准确度较高,其平均绝对误差及平均相对误差分别为0.026g/L和0.062%.  相似文献   

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