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1.
蜂蜜中多种有机磷农药残留的液相色谱串联质谱检测   总被引:1,自引:0,他引:1  
针对敌百虫、敌敌畏和蝇毒磷为常用的防治蜜蜂天敌或虫害的有机磷农药杀虫剂,易在蜂蜜中产生残留,建立了蜂蜜中敌百虫、敌敌畏和蝇毒磷残留的液相色谱串联质谱(LC-MS/MS)同时测定方法。蜂蜜样品经乙酸乙酯提取、浓缩,用甲醇溶解残渣,液相色谱(LC)分离,电喷雾(ESI)-MS/MS多反应监测(MRM)模式检测,外标基体曲线定量。3种有机磷农药在20~500μg/L范围内线性响应良好,相关系数均大于0.994;获得的检出限均为0.1μg/kg,定量限均为4μg/kg。在加标浓度为10~40μg/kg范围内,平均回收率为78.5%~96.8%,相对标准偏差为9.1%~13.1%。  相似文献   

2.
三唑磷和乙酰甲胺磷对海洋桡足类的急性毒性研究   总被引:3,自引:0,他引:3  
研究了三唑磷和乙酰甲胺磷两种常用有机磷农药对婆罗异剑水蚤和日本虎斑猛水蚤的急性毒性,报道了相关的24hLC50和48hLC50数据.其中三唑磷对婆罗异剑水蚤和日本虎斑猛水蚤的48hLC50分别为6.844μg/L和16.26μg/L,而乙酰甲胺磷对婆罗异剑水蚤和日本虎斑猛水蚤的48hLC50分别为216.3 mg/L和76.54 mg/L.结果表明:对两种桡足类而言,三唑磷的毒性大于乙酰甲胺磷;桡足类对有机磷农药的耐受性具有种的特异性.据此提出使用农药的相关建议,指出应该严格控制三唑磷的使用,为近岸海区环境的质量评价和污染防治提供参考依据,并为监测有机磷农药污染环境提供了参考资料.  相似文献   

3.
建立了一种改良的QuEChERS前处理结合气相色谱-三重四极杆串联质谱(GC-MS/MS),快速便捷同时检测西红花中9种有机磷农药残留的方法.样品用1%乙酸-乙腈溶液提取,经改良QuEChERS法净化,以GC-MS/MS采取多反应离子监测模式检测,基质校准曲线外标法定量.在2.0~100.0μg/kg浓度范围内,9种有机磷农药线性关系良好,相关系数(r~2)均大于0.999;检出限为0.5~1.3μg/kg,定量限为2.0~3.2μg/kg.平均加标回收率为73.2%~103.9%,相对标准偏差为0.64%~6.1%(n=6).本方法快速方便、准确度和灵敏度良好,适用于西红花中有机磷农药多残留的检测.  相似文献   

4.
提出环境水样中有机磷农药残留的固相萃取-液相色谱分析方法.水样用0.22μm水系膜过滤两次,C18固相萃取小柱分离富集,用乙腈洗脱目标物,洗脱液直接进行液相色谱分析.结果显示,工作曲线范围分别为甲基对硫磷2.0~80μg/L、杀螟硫磷3.0~80μg/L、对硫磷3.0~100μg/L、辛硫磷5.0~100μg/L、检测限(LOD)分别为甲基对硫磷0.11μg/L、杀螟硫磷0.52μg/L、对硫磷0.45μg/L、辛硫磷0.85μg/L.加标回收率在84.2%~102.2%范围内.该方法操作简单、快速、低成本、高回收率、富集效果好,适合于环境水样中有机磷农药残留的分析检测.  相似文献   

5.
目的利用便携式流动注射化学发光仪和紫外降解装置,检测蔬菜中残留的有机磷农药。方法过硫酸钾在紫外光的催化下能将有机磷降解为无机磷,无机磷在酸性条件下可以和钒酸盐、钼酸盐反应生成具有氧化性的磷钼钒杂多酸,可直接氧化鲁米诺产生强而稳定的化学发光信号;根据发光强度与磷的浓度在一定范围内呈线性关系,从而实现有机磷农药的定量测定。结果测定磷的检出限为1.0×10-10g/mL,线性范围为1.0×10-9~3.0×10-6g/mL,对浓度为2.0×10-7g/mL的磷平行测定11次,相对标准偏差为2.1%;当青菜中有机磷农药的添加浓度为1.00 mg/kg和2.00 mg/kg时,方法回收率在89.5%~113.5%之间。结论此方法简便快捷、准确可靠,实现了检测仪器的自动化和微型化,为市售蔬菜中有机磷农药残留的现场检测奠定了基础。  相似文献   

6.
椭圆背角无齿蚌对重金属元素的积累作用   总被引:9,自引:0,他引:9  
 检测了滇池水饲养1a的椭圆背角无齿蚌(Anodonta woodiana elliptica)体内重金属等元素含量,结果显示椭圆背角无齿蚌体内锌含量为7.08×102mg/kg,铅为35.68mg/kg,铜为9.04mg/kg,铁为4.74×103mg/kg,砷为62.09mg/kg,磷为4.44×104mg/kg.与滇池水中锌0.0205μg/L,铅0.412μg/L,铜3.198μg/L相比较,表明椭圆背角无齿蚌对锌、铅、铜有很强的富集能力.  相似文献   

7.
金银花等3种中药材中有机磷农药残留量的测定   总被引:2,自引:0,他引:2  
对中药材金银花中11种有机磷农药残留量的气相色谱方法进行了研究.样品中的农药采用乙腈-水系统提取,经氮吹浓缩,选用火焰光度检测器(FPD)和DA-5毛细管柱,采用程序升温,气相色谱法检测.方法的最低检出浓度为1.0×10-3~6.0×10-3μg/mL,仪器精密度为1.4%~4.7%;方法精密度为1.2%~6.0%;加样回收率为88.0%~104.6%,RSD值为2.6%~8.9%.用该方法对金银花、泽泻和川芎中有机磷农药残留量进行了测定,结果表明,3种中药材均不同程度地受到有机磷农药的污染,依照《欧洲药典》7.0版农药残留最大限量规定,金银花不合格率为60%,泽泻不合格率为40%,川芎不合格率为10%.  相似文献   

8.
建立了苹果中有机磷农药残留多组分同时定量分析的离子液体分散液液微萃取-高效液相色谱分析(IL-DLLME-HPLC)方法.以[C_6MIM][PF_6]离子液体为萃取剂,甲醇为分散剂,对样品体积、萃取温度和萃取时间等萃取条件进行优化.结果显示,苹果样品中哒嗪硫磷、对硫磷、倍硫磷和伏杀硫磷4种有机磷在20~2 000μg/kg范围内线性关系良好,检出限为5.7~8.4μg/kg,加标回收率在85.3%~101.1%范围内,富集倍数为246~273.该方法回收率和富集倍数高,适用于苹果中有机磷农药残留的多组分同时分析.  相似文献   

9.
在邕江南宁段和南宁城市内河的西明江、可利江、心圩江、朝阳溪、大桥冲、水塘江、竹排冲设置采样点,分别在枯水期和丰水期采集水样,用固相萃取-气相色谱/脉冲火焰光度检测器检测三乙基偶磷硫酯、硫磷嗪、致螟磷、甲拌磷、乐果、乙拌磷、甲基对硫磷、对硫磷和氨磺磷9种有机磷农药的含量,分析水体中有机磷农药组成及污染状况。结果共检出甲拌磷、乐果、乙拌磷、对硫磷、甲基对硫磷和氨磺磷6种有机磷农药。邕江南宁段仅在丰水期检出乐果和氨磺磷2种有机磷农药,含量0.03~0.04μg/L。南宁城市内河枯水期检出甲拌磷、乐果、乙拌磷、对硫磷4种有机磷农药,总含量0.09~6.82μg/L,含量最高的是朝阳溪的样品;丰水期检出乐果、乙拌磷、甲基对硫磷、氨磺磷4种有机磷农药,总含量0.08~6.60μg/L,含量最高的是大桥冲的样品。  相似文献   

10.
通过比较不同的提取剂和吸附剂对水产品的净化效果和对质谱基线的影响,建立一种有效的水产品中有机磷农药多残留的气相色谱-三重四极杆串联质谱(GC-MS/MS)方法。用正己烷对样品进行提取处理,采用N-丙基二乙胺(PSA)和硅胶柱进行固相萃取,用GC-MS/MS多反应离子监测(MRM)模式测定。结果表明,在5~200μg·L-1范围内,28种有机磷农药的峰面积与对应的质量浓度间呈良好的线性关系,相关系数R20.996 8,方法的定量限(S/N=10)为0.2~7.9μg·kg-1,在大黄鱼中各农药的回收率为67%~99%之间,相对标准偏差(RSD)在5.3%~13.6%(n=6)之间,在南美白对虾中各农药的回收率为73%~106%之间,相对标准偏差(RSD)在4.6%~12.8%(n=6)之间。该方法较为灵敏、准确、简便,可用于检测水产品的有机磷农药残留情况。  相似文献   

11.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

12.
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   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to  相似文献   

15.
Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications (up to 574.8 km/ h test speeds or 380 km/h commercial speeds) in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.  相似文献   

16.
17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.  相似文献   

19.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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