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71.
建立了超声提取-气相色谱质谱法测定大气PM2.5中32种正构烷烃方法,经离子温度优化、前处理比较、空白滤膜考察等获得了最佳的实验条件。研究发现,高、中、低3种浓度标准曲线的相关系数均在0.995以上,3种浓度的空白样品加标回收率分别为72.2%~117.8%、73.5%~104.4%、73.8%~109.5%,精密度均小于10%,实际样品加标回收率为75.7%~108.9%。当采样体积为24 m3时,各目标化合物的方法检出限为0.046~2.6 ng/m~3;经正构烷烃浓度范围为0.17~64.3 ng/m~3的1月及浓度范围为0.53~7.67 ng/m~3的6月的实际样品验证,该方法的检出限和测量范围也可较好的满足实际样品的测定。  相似文献   
72.
鄯善采油厂油田回注水水质劣化原因及对策   总被引:1,自引:0,他引:1  
鄯善采油厂4 000 m3/d污水处理站于2000年11月投运,采用"水力旋流 聚结斜管除油 两级精细过滤"的处理方式.注水水质变化表现为来水经净化处理后水质有较大改善,但从清水罐到注入井段水质又存在变坏的问题,为此提出鄯善采油厂回注水水质稳定技术研究.通过对处理系统和注水系统全程的水质各个指标的监测,保证注水水质的稳定.分析了造成水质不稳定的因素,对水质劣化的机理进行了阐述,并提出相应的水质稳定措施.  相似文献   
73.
Extracellular polymeric substances(EPS) produced by microorganisms represent biological macromolecules with unfathomable potentials and they are required to be explored further for their potential application as a bioflocculant in various wastewater sludge treatment. Although several studies already exist on biosynthetic pathways of different classical biopolymers like alginate and xanthan, no dedicated studies are available for EPS in sludge. This review highlights the EPS composition, functionality, and biodegradability for its potential use as a carbon source for production of other metabolites. Furthermore, the effect of various extraction methods(physical and chemical) on compositional, structural, physical and functional properties of microbial EPS has been addressed. The vital knowledge of the effect of extraction method on various important attributes of EPS can help to choose the suitable extraction method depending upon the intended use of EPS. The possible use of different molecular biological techniques for enhanced production of desired EPS was summarized.  相似文献   
74.
Solution 31P nuclear magnetic resonance spectroscopy (31P-NMR) is a useful method to analyze organic phosphorus (Po), but a general procedure for the analysis method is lacking. The authors used solution 31P-NMR, which was found to be an effective method for analysis of Po in Haihe River sediment, to analyze the Po in the surface sediment in Eastern China at the regional scale, and found that the NaOH-ethylenediaminetetraacetic acid (EDTA) extraction rate was affected by environmental factors. At the regional scale, the extraction rate showed a positive relationship with loss on ignition, when the extraction rate was lower than 60%. The extraction rate had no relationship with the loss on ignition when the extraction rate was higher than 60%. The extraction rate showed a negative relationship with pH, which means that the extraction rate was higher in acidic sediment and lower in alkaline sediment. The ratio of TC/TN (the ratio of total carbon to total nitrogen) was considered to represent the origin of organic matter in the sediment. The extraction rate was high when the TC/TN ratio was lower than 20, meanwhile the extraction rate decreased as the TC/TN ratio increased. The results show that the origin of organic matter in sediment significantly affects the NaOH-EDTA extraction rate. This study will give theoretical support for building an effective and general solution 31P-NMR analysis method.  相似文献   
75.
荧光法测定水中微量油有关萃取条件的讨论   总被引:2,自引:0,他引:2  
荧光法测定水中微量油有关萃取条件的讨论张丹丹(南通市环境科学研究所)DISCUSSIONONTHEEXTRACTIONCONDITIONSOFMEASURINGMINOROILINTHEWATREBYFLUORESENCEMETHOD¥ZhangDa...  相似文献   
76.
选用HLB固相萃取小柱进行富集,用二氯甲烷进行洗脱,优化了固相萃取过程,建立了固相萃取-气相色谱质谱法测定地表水中7种藻致嗅味物质的方法,浓度在0.004~0.1 mg/L范围内线性关系良好,具有较高的灵敏度和精密度,方法检出限为1×10-6~2×10-6mg/L,加标回收率为85.9%~108.6%,适用于地表水中嗅味物质的检测。  相似文献   
77.
对红外分光光度法测定水质石油类和动植物油中萃取设备和脱水方法进行改进,用采样-自动萃取联体装置来萃取样品,提高该方法操作规范化程度,解决了沙芯漏斗难清洗及交叉污染的问题;提高了样品前处理自动化程度,减少待测物质损失,提高方法精密度和准确度;减轻分析人员劳动强度,提高了工作效率;最大程度减少萃取过程四氯化碳对分析人员的毒害,能更好适应当今日益繁重的监测任务。  相似文献   
78.
紫外线吸收剂废水属于典型高浓度有机酸性高盐废水,难以生物降解,首先分析了紫外线吸收剂废水国内外处理现状,然后介绍江苏省某紫外线吸收剂企业废水处理工程的工艺参数、调试过程和运行效果,并对相关问题进行了分析,最后进行了总结。工程设计处理能力为240 m3/d,采用蒸发析盐和萃取分质处理并结合生化工艺,出水水质指标达到并高于化工园区废水接管标准。该处理工艺的成功运行对于同行业废水治理具有一定参考价值。  相似文献   
79.
采用索氏提取、超声波萃取方法与高效液相色谱技术相结合对扎龙底泥中邻苯二甲酸二丁酯(DBP)和邻苯二甲酸(2-乙基己基)酯(DEHP)进行测定。  相似文献   
80.
A 1-dodecanethiol-based phase-transfer protocol is developed for the extraction of noble metal ions from aqueous solution to a hydrocarbon phase, which calls for first mixing the aqueous metal ion solution with an ethanolic solution of 1-dodecanethiol, and then extracting the coordination compounds formed between noble metal ions and 1-dodecanethiol into a non-polar organic solvent. A number of characterization techniques, including inductively coupled plasma atomic emission spectroscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis demonstrate that this protocol could be applied to extract a wide variety of noble metal ions from water to dichloromethane with an efficiency of > 96%, and has high selectivity for the separation of the noble metal ions from other transition metals. It is therefore an attractive alternative for the extraction of noble metals from water, soil, or waste printed circuit boards.  相似文献   
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