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1.
路俊杰  候伟东 《科技资讯》2012,(12):137-137
在经济高速发展的今天,环境污染问题越来越严重,人们的环保意识也在不断的增强,有机物对环境带来的污染尤其受到关注。固相微萃取法本身具有快捷、方便、价廉以及灵敏等优势,是一种样品前进行处理的新技术,而且已经被广泛地用到了对环境监测之中。文章介绍了环境监测中固相微萃取法的含义,分析了固相微萃取法在土壤环境监测、水源环境监测以及大气环境监测中的应用。  相似文献   

2.
赵璐  左志芳 《科技信息》2012,(36):138-138
本文介绍了中药千年健的主要化学成分及水蒸气蒸馏法、固相微萃取法、临界CO2萃取法和微波辅助溶剂萃取法等多种方法在千年健提取加工中的应用,并对千年健的应用前景进行了展望。  相似文献   

3.
采用固相微萃取法(SPME)和同时蒸馏萃取法(SDE)提取牛角瓜中挥发性成分,联合气质联用技术进行分析.结果表明,利用两种提取方法从牛角瓜中共鉴别出163个化合物,其中固相微萃取法鉴定了81个化合物,而同时蒸馏萃取法鉴定了82个化合物,共有的化合物为30个.  相似文献   

4.
查阅近些年国内外公开发表的文献,简述了我国茶叶生产上常用农药情况,比较了国内外茶叶农药残留最大限量标准,综述了茶叶中农药残留的主要检测技术,重点对固相微萃取法、液相微萃取法、分散固相萃取法等样品前处理技术,以及气相色谱法、液相色谱法、质谱法、免疫分析法等检测技术在茶叶农药残留分析中的应用及特点进行了总结,并对其发展方向进行了展望,以期为今后开展茶叶中农药残留的分析研究提供参考。  相似文献   

5.
室内空气中酞酸酯类物质分析的研究   总被引:1,自引:0,他引:1  
以固相微萃取(SPME)方法为前处理和分离手段采集室内空气中的酞酸酯类物质,进而在GC/MS上对其进行分析测定。通过对SPME中使用的极性与非极性纤维萃取头的萃取效果进行对比.确立了该类室内空气中酞酸酯类物质的分离和分析方法.并且比较了不同环境中室内各种邻苯二甲酸酯类的相对浓度大小。实验发现.与用传统的有机溶剂吸收空气中的化合物的方法相比.该方法可以检测出低浓度邻苯二甲酸二(2-乙基己基)酯(DEHP).并且简化了实验过程.减少了干扰及有机溶液的使用量.并可以测定出浓度较低的酞酸酯类物质。  相似文献   

6.
顶空固相微萃取法测定饮用水中的氯仿、四氯化碳   总被引:2,自引:0,他引:2  
采用顶空固相微萃取(HSPNE)测定饮用水中的氯仿,四氯化碳,具有快速,简便,分离效果好,重现性好的实验结果,能达到国家标准方法的要求,结果表明顶空固相微萃取在饮用水分析中具有很好的应用前景。  相似文献   

7.
利用固相微萃取-气相色谱质谱法(SPME-GC/MS)分析室内空气中和不同材质的新家具释放出的挥发性有机物。优化的固相微萃取试验条件:选用65μm PDMS/DVB萃取纤维吸附样品挥发出的有机物,空气样品吸附时间为6h,家具样品吸附时间为20min,解析时间为5min,解析温度为250℃。对置入4种不同板材制成的家具前后的室内空气样品进行分析,发现4种板材制成的家具均给室内空气引入了新的挥发性有机物,芳香烃和萜烯类物质是实木颗粒板家具引入的的主要有机物,苯乙烯是中密度板家具引入的主要有机物,萜烯类和醇类化合物是大芯板和实木板家具引入的主要有机物。该方法可以快速、准确地分析室内空气中的挥发性有机物,为室内空气质量检测提供新的有效手段。  相似文献   

8.
硅藻土固相萃取在毒物分析中的应用   总被引:1,自引:0,他引:1  
硅藻土固相萃取的特点是操作简便快速,提取率高,提取液干净,多数文献以此认为该法比液液萃取、亲脂性材料或混合型材料固相萃取法优越;少数文献的比较结果是亲脂性材料或混合型材料固相萃取法优越。已报道的用硅藻土固相萃取法提取的毒物种类很多,包括杀虫剂、杀菌剂、除草剂、各类药物及对人畜有毒的其他有机化合物等。  相似文献   

9.
本文介绍了固相微萃取-气相色谱法测定水中苯、甲苯、乙苯和二甲苯的含量作为教学实验及其实验方法、内容和步骤,并讨论了该实验在教学实践中的可行性和必要性、存在的优点以及预期的教学效果。  相似文献   

10.
采用顶空固相微萃取-气相色谱-质谱联用法(HS-SPME-GC-MS)分离鉴定藿香正气丸中的挥发性成分,通过筛选固相微萃取纤维,优化固相微萃取操作条件,并采用GC-MS对解析物进行分离鉴定.共鉴定出73种组分,主要为烃类倍半萜类化合物.其中,广藿香醇含量最高,为17.6%.结果表明,本实验方法适用于藿香正气丸中挥发性成分的快速分析.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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