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1.
常压微波技术萃取土壤中有机氯农药   总被引:7,自引:3,他引:7  
汪雨  张玲金 《岩矿测试》2006,25(1):15-18
利用常压微波萃取技术提取土壤样品,经佛罗里硅土柱净化后用气相色谱检测(电子捕获检测器)其中13种有机氯农药。试验了丙酮/正己烷混合溶液的提取条件,考察了提取时间、提取温度和提取功率对提取效率的影响,并与索氏提取及超声波提取进行比较。在优化的萃取条件下,常压微波萃取20min重复测定的平均回收率为84.26%-105.2%,相对标准偏差(RSD,n=5)为0.52%-18.6%。方法的检出限为0.033—0.853ng/g。  相似文献   

2.
目的:探讨紫外分光光度法测定秋水仙碱中毒血清,为临床秋水仙碱中毒提供诊疗依据。方法取0.5 mL 血清加提取液(三氯甲烷∶甲醇=95∶5)4.0 mL。充分震荡萃取,高速离心,取有机层于另一试管中氮气吹干,取0.2 mL 甲醇溶解残渣,混匀,取50 mL 做紫外扫描。结果血清中秋水仙碱最大吸收峰(351±1)nm,浓度在5.0~40μg/mL 范围内呈线性,回归方程Y =0.0502X +0.0013,其相关系数为0.9995,回收率为83.8%~102.8%,相对标准差为3.3%~4.8%。日内、日间相对标准差分别为3.22%~4.74%和3.45%~4.66%,最低检出浓度为1.0μg/mL。结论该方法操作简便,分析快速,结果准确,为临床诊断秋水仙碱中毒提供了一个简便准确的检测方法。  相似文献   

3.
C18固相膜萃取-气相色谱法测定饮用水中12种有机氯农药   总被引:13,自引:10,他引:13  
利用C18固相萃取膜提取水样,气相色谱法(电子捕获检测器)测定饮用水中12种有机氯农药。对洗脱液、水样pH值、萃取压力等条件进行了优化选择,并与液-液萃取做了比较。结果表明,与液-液萃取相比,固相膜萃取具有操作简单、富集倍数高、节省溶剂和耗时短等优点,是萃取水中有机氯农药的有效方法。12种有机氯农药的回收率为85.97%~127.7%,相对标准偏差(RSD,n=5)为4.74%~12.2%,方法检出限为0.014~0.047μg/L。  相似文献   

4.
研究了聚乙二醇-2000水溶液在硫酸铵存在下分为液-液两相的条件和二溴羧基偶氮氯膦与Pd(Ⅱ)反应生成的配合物在该萃取体系两相间的分配行为,实现了Pd(Ⅱ)的定量萃取分离。在此基础上建立了非有机溶剂液-液萃取分光光度法测定微量Pd(Ⅱ)的新方法。该方法的检出限为0.03mg/L,线性范围为0.09~2.0mg/L,在最佳实验条件下,萃取率达94%。方法用于铂钯二次精矿和人工合成样品中微量钯的测定,相对标准偏差(RSD,n=5)≤2.4%,加标回收率为96%-103%。  相似文献   

5.
研究了碘化钾-甲基异丁基甲酮(KI—MIBK)萃取-火焰原子吸收分光光度法连续测定地球化学样品中痕量银、镉和铊的主要条件。通过对火焰原子吸收分光光度计气路控制系统及雾化器的改进,较大地改善了萃取-火焰原子吸收分光光度法测定银、镉和铊的稳定性和灵敏度。选择萃取酸度为1.2mol/L HCl、水相和有机相体积配比为3:1~4:1,方法精密度(RSD,n=12)为Ag4.5%~9.6%、Cd1.5%~7.9%、T14.5%~5.4%,检出限(3s)为Ag0.004μg/g、Cd0.007μg/g、T10.011μg/g,符合多目标地球化学调查样品测试及质量监控要求。用国家一级标准物质和密码组合标准物质进行验证,测试结果令人满意。  相似文献   

6.
木质素分解产物酚类化合物是指示海洋环境中陆源有机碳来源的重要生物标志物,因此,开发检测海洋沉积物中木质素分解产物酚类化合物的简便方法,对研究海洋有机碳的来源及生物地球化学循环过程具有重要意义。本文采用固相萃取(SPE)和超高效液相色谱-飞行时间质谱技术(UHPLC-TOF/MS),建立了一种同步测定海洋沉积物中木质素分解产物酚类化合物(11种)的方法。首先对海洋沉积物样品进行氧化铜氧化碱分解和SPE净化处理,再采用填料粒径为1.8μm的反相C18柱进行分离,电喷雾TOF/MS全扫描模式检测,内标法定量。结果表明:沉积物中木质素的11种主要分解产物酚类化合物在20min内分离良好;方法具有良好的精密度(相对标准偏差RSD均小于9.0%),在线性范围内相关系数(R2)均不小于0.9989,加标回收率在86.8%~93.2%之间。应用该方法对莱州湾表层沉积物中木质素分解产物酚类化合物进行测定,12个表层沉积物样品中11种目标化合物的检出率均为100%;相关诊断比值:肉桂基酚系列单体总量与香草基酚系列单体总量的比值C/V在0.18~0.81之间,均值为0.38;丁香基酚系列单体总量与香草基酚系...  相似文献   

7.
水杨基荧光酮-石蜡相分光光度法测定植物中痕量锗   总被引:1,自引:0,他引:1  
陶慧林 《岩矿测试》2006,25(2):140-142
介绍了以锗-水杨基荧光酮-石蜡为体系,石蜡相分光光度法测定植物中的锗,探讨了该方法的最佳实验条件。结果表明,在HCl介质中,锗与水杨基荧光酮形成的络合物被萃取至蜡相后,于506 nm处有最大吸收,其εmax=2.3×105L·mol-1·cm-1,锗含量在0-0.40 mg/L 符合比尔定律,精密度(RSD,n=8)为2.7%-4.3%,回收率为96%-110%。方法应用于植物中锗的测定,结果满意。  相似文献   

8.
气相色谱法测定水中丙烯酰胺   总被引:2,自引:0,他引:2       下载免费PDF全文
张宗祥  杨文武  陈军 《江苏地质》2009,33(2):196-198
采用溴化衍生-气相色谱法测定水中的丙烯酰胺,方法检测限为0.02μg/L,平均加标回收率为99.1%~104.5%,相对标准偏差为0.8%~2.6%,方法实用准确。  相似文献   

9.
对磷矿石中P2O5、Al2O3,caO、MgO、Fe2O3、Cd测定方法进行研究,确定试验最佳条件。元素回收率95.3%~105.4%,相对标准偏差(n=12)为2.53%-5.80%,检出限为0.5×10^-6-7.86×10^-6。经几种国家标准物质及矿石样品分析验证,结果满意。  相似文献   

10.
为了初步掌握中国主要城市地下水挥发性卤代烃污染状况和特征,在中国69个城市开展了地下水挥发性卤代烃污染检测与特征研究,采集地下水样品791组,采样井均为工农业生产和生活饮用水水井;依据USEPA8260B检测方法,采用气相色谱/质谱联用分析仪器(P&T—GC/MS),分析和测试了氯仿、四氯化碳、1,1,1-三氯乙烷、三氯乙烯、四氯乙烯和二氯甲烷等15种挥发性卤代烃的质量浓度。结果表明:在791组地下水样品中,有406组样品至少有一种挥发性卤代烃组分被检出,检出率为51.33%;各组分中,氯仿的检出率最高,为20.35%,其他组分的检出率为0.25%~5.06%;氯乙烯在所有样品中均未检出;有13组样品的单项组分超标,超标率为1.64%;超标率由高到低分别为四氯化碳(0.76%)、氯仿(0.25%)、1,2-二氯乙烷(0.25%)、三氯乙烯(0.13%)、1,1,2-三氯乙烷(0.13%)、1,2-二氯丙烷(0.13oA);超标井均为非供水水源地水井。检测与研究结果表明:中国主要城市地下水挥发性卤代烃污染物检出率较高,检测的69个城市中719/6的城市至少有一种挥发性卤代烃被检出,且潜水的检出率高于承压水,但总体超标率较低。  相似文献   

11.
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.  相似文献   

12.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.  相似文献   

13.
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.  相似文献   

14.
Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ1 roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003).  相似文献   

15.
正The Kuqa depression deposited thick rock salt,which has a lower density than surrounding rocks.When salt bodies form a certain scale,obvious negative gravity anomalies can be detected in the surface.Therefore,gravitational method can quickly obtain the shape,plane distribution of deep-seated salt bodies and overall tectonic morphology of the basin.  相似文献   

16.
正1 Introduction The Pingluoba brine,which characterized as high concentration with sodium,potassium,boron,lithium,and rubidium,possess great development value.The main composition of the brine can be summarized to the  相似文献   

17.
正1 Introduction In the present paper,MgCl2·6H2O,FeCl3·6H2O,and CeCl3·6H2O were used as raw materials in the precipitationhydrothermal method to synthesize MgF eC e hydrotalcite.The effects of the Fe:Ce molar ratio on the composition,crystal structure,and thermal stability of hydrotalcite are examined.Energy-dispersive X-ray spectroscopy(EDS),X-  相似文献   

18.
正1 Introduction Crystallization is one of important unit operations in the chemical production process,which requires not only the crystal product with high purity and yield,but also the available particle size of the crystal products to ensure product quality.Crystallization process is affected by  相似文献   

19.
正Dear Authors and Readers:First of all,on behalf of the new Editorial Board,I would like to express our sincere appreciation for your continuing support of our journal.This journal,founded in 1922,is the oldest geological journal in China.As the flagship journal of the Geological Society of China,it has become more and more influential in earth sciences in China and beyond.The journal is now indexed by SCI,CA and more than 20 other databases,with an impact  相似文献   

20.
正20141283 Bai Daoyuan(Hunan Institute of Geological Survey,Changsha 410016,China);Zhong Xiang Nature,Origin and Tectonic Setting of Jinzhou Basin in the South Segment of Xuefeng Orogen(Geology in China,ISSN1000-3657,CN11-1167/P,40(4),2013,p.1079-1091,10 illus.,47 refs.)Key words:foreland basins,strike-slip faults,Hunan Province  相似文献   

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