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1.
建立了树脂动态分离-氢化物发生-原子荧光光谱法测定中成药中痕量As(Ⅲ)和As(Ⅴ)的分析方法.研究了盐酸浸提和树脂分离的最佳条件,探讨了仪器的工作条件、试剂浓度及不同增感剂对砷原子荧光强度的影响.成功地对5种中成药中的砷进行了形态分离及分析.方法检出限为84.9 ng/L,RSD为1.41 %.回收率为90.8%~110.2%.  相似文献   

2.
砷形态分析方法   总被引:3,自引:0,他引:3  
建立了水环境中的4种砷形态亚砷酸(As(Ⅲ))、砷酸(AS(V))、一甲基砷酸(MMA)、二甲基砷酸(DMA)的形态分析方法.在pH 6.0磷酸盐作流动相、梯度洗脱条件下,4种砷形态在IC-Anion-PW阴离子交换色谱上获得了分离.以20g/L的KzS2 08溶液作氧化荆,紫外催化氧化消解,可使有机砷完全转化为无机态的As(V).并在10%的盐酸栽流、20g/LKBH4+5g/LKOH溶液为还原剂的条件下,实现了氢化发生原子荧光检测.将所建立的方法用于地下水样品的测定,4种形态砷系物在O~20mg/L的质量浓度范围内都表现出良好的线性关系.各检出限均保持在约0.1/g/L水平,回收率控制在95%~110%以内,相对标准偏差≤3%.  相似文献   

3.
用氢化物发生-原子荧光光谱法测定城市污水中总砷,确定了试验的最佳测定条件。结果表明砷的测定线性范围为5~50ng/mL,回收率100%~103%,测定6条标准曲线的剩余标准差为1.3,检出限为0.26ng/mL,该方法可用于测定其它不同水体中的总砷。  相似文献   

4.
珠江广州河段底泥中砷的形态分析   总被引:1,自引:0,他引:1  
对底泥中4种结合态的几种形态砷(As(Ⅲ)、As(Ⅴ)、甲基胂酸盐和二甲基胂酸盐)的测定表明,底泥中砷的污染严重,平均为41.7ppm.酸溶解态、碱溶解态和残渣态含砷量分别占72.4%、8.8%和18.9%,水溶态含砷量为全砷量的千分之几(ppb级).各结合态中都以无机砷为主,As(Ⅲ)占多数,占总砷量1/2以上;有机砷占总砷量1/2左右,以二甲基胂酸盐为主.  相似文献   

5.
6-氨基青霉烷酸终产品中,苯乙酸的质量百分比必须低于0.1%,使得二者很难同时进行定量检测.文章建立了6-氨基青霉烷酸中苯乙酸杂质的直接检测方法.将已知浓度的苯乙酸标准品溶液在检测前加入到样品溶液中,采用Hypersil ODS-2 C18色谱柱(100 mm×4.6 mm,5μm),以比例为99∶1的磷酸盐缓冲溶液和乙腈的混合液作为流动相,220 nm为检测波长、1.0 mL/min的流量和25℃的柱温下进行检测.终产品中6氨基青霉烷酸与苯乙酸可完全分离,其中苯乙酸标准溶液在0.3022~3.022×10-3 mg/mL浓度范围内线性良好,线性系数R>0.999 8,检出限为15.26 ng/mL,回收率大于85%,该方法精密度为0.82%(n=6),符合国家标准.  相似文献   

6.
以2'-(4-甲基-2-噻吩亚甲基)-3,5-二羟基苯甲酰腙镍(MTHBM-Ni) 配合物作荧光探针,用荧光光度法测定了氧氟沙星(OFLX)片中OFLX的含量.实验结果表明,当底液中MTHBM-Ni的加入量为0.8 mL时,OFLX的检出限为0.16 ng/mL,线性范围为(0.003 3~9.45)μg/mL.方法用于OFLX片剂中OFLX的测定,RSD 1.4%(n=6),平均回收率为95.70%.  相似文献   

7.
合成了试剂α-(4-氨基安替比林偶氮)-β-萘酚(AAP-NP),研究了试剂的光度性质.实验表明,pH在1.5~3.0范围内,铁(Ⅲ)与AAP-NP形成1∶2配合物,其最大吸收波长为300 nm,表观摩尔吸光系数ε=6.72×10-4L.mol-1.cm-1,铁含量在0~11/25μg/mL范围内与吸光度呈良好的线性关系,线性回归系数r=0.999 9,方法检出限为1.6 ng/mL.将该方法用于茶叶、木耳、缸豆和水中微量铁(Ⅲ)的测定,结果满意.  相似文献   

8.
石墨炉原子吸收法测定黄芪甘草和广藿香中的铅   总被引:2,自引:0,他引:2  
用硝酸-高氯酸混合酸(4∶1)消化黄芪、甘草和广藿香,用石墨炉原子吸收光谱法测定黄芪、甘草和广藿香中的铅.在选定实验条件下,线性范围为0 ng/mL~20 ng/mL检出限为0.113 ng/mL,回收率为98.2%~100.9%,相对标准偏差为0.2%.  相似文献   

9.
为采用阳极溶出伏安法(ASV)测定不同形态的砷(As),优化了pH值、沉积电位、沉积时间和支持电解质等影响因素.结果表明:该体系在1~100μg/L峰电流与As(Ⅲ)的浓度呈现良好的线性关系,相关系数为0.998,检出限为37.5 ng/L,8次重复测定10μg/L As(Ⅲ)RSD为1.27%.该方法可通过还原As(V)为更有电活性的As(Ⅲ)来实现As(V)的测定,可用于检测自来水样品中超痕量As(Ⅲ)和As(V),测定结果与电感耦合等离子质谱结果相一致,实现了不同形态砷的测定.  相似文献   

10.
建立了同时从沉积物中提取亚砷酸盐As(Ⅲ)、砷酸盐As(Ⅴ)、一甲基砷酸(MMA)和二甲基砷酸(DMA)4种砷形态的提取方法以及HPLC-ICP-MS联用测定沉积物中4种砷形态化合物的检测方法.探讨了磷酸、抗坏血酸、水浴时间等前处理条件,以及C8色谱柱和Hamilton PRP-X100色谱柱的色谱分离条件,由此建立了沉积物中砷形态的检测方法.结果表明,在95 ℃条件下水浴60 min,提取剂选择0.3 mol/L磷酸和0.5mol/L抗坏血酸的混合溶液,4种砷形态化合物加标回收率在70%-110%之间,相对标准偏差(RSD)小于6%.选用Hamilton PRP-X100(5 μm×15 cm)色谱柱进行4种砷形态的分离,以15 mmol/L磷酸氢二铵溶液(用甲酸调节pH=6.0)为流动相,在7 min内同时分析检测4种砷形态化合物,As(Ⅲ)、DMA、MMA和As(Ⅴ)的检出限依次为0.22、0.60、0.28和0.78 μg/L.该方法实现了对沉积物中常见的不同形态砷的同时分析,具有灵敏度高、精密度好的特点.  相似文献   

11.
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   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
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   

14.
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   

15.
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   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
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   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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