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1.
胶束增敏荧光光度法测定苯甲酸雌二醇的研究   总被引:1,自引:0,他引:1  
本文报道了高灵敏度荧光增效法测定苯甲酸雌二醇(EB)的新方法。在表面活性剂溴化十六烷基三甲铵(CTMAB)存在下,测定下限为4.0×10-9mol·L-1,线性范围为4.2×10-9~3.8×10-6mol·L-1。本法应用于样品中苯甲酸雌二醇的测定,结果满意。  相似文献   

2.
研究了新荧光试剂3 ,5 - 二溴水杨醛缩4 - 氨基安替比林( 简称:3 ,5 - DBSAAP) 与铜的荧光猝灭反应体系的最适宜的条件。3 ,5 - DBSAAP 发射强的荧光,λex/em = 393nm/510nm 。在pH9 .0 的NH3 - NH4Cl 缓冲介质中,Cu( Ⅱ) 与3 ,5 - DBSAAP在室温反应使其荧光猝灭。据此建立了铜的分析方法,线性范围为1 .6 ×10 - 5 mol/L~1 .2 ×10 - 7 mol/L。用于测定人发中的铜,结果满意。  相似文献   

3.
锌—水杨基荧光酮—CTMAB体系荧光特性的研究及应用…   总被引:1,自引:0,他引:1  
研究了锌-水杨基荧光酮(SAF)-溴化十六烷基三甲胺(CTMAB)体系的荧光特性。实验结果表明,在pH9.75 ̄10.35的H3PO4-HAc-H3BO3缓冲介质中,产生荧光熄灭程度最大的激发波长为λex=524nm,荧光波长为λem=549nm。当锌含量0 ̄2.4μg/25ml范围内,荧光熄灭程度与浓度呈线性关系,藉以测定微量锌。方法简便,快速,稳定性高,可应用于食品及环境水样中微量锌的测定。  相似文献   

4.
研究了锌-水杨基荧光酮(SAF)-溴化十六烷基三甲胺(CTMAB)体系的荧光特性.实验结果表明,在pH9.75~10.35的H3PO4-HAc-H3BO3缓冲介质中,产生荧光熄灭程度最大的激发波长为λex=524nm,荧光波长为λem=549nm.当锌含量0~2.4μg/25ml范围内,荧光熄灭程度与浓度呈线性关系,藉以测定微量锌.方法简便,快速,稳定性高,可应用于食品及环境水样中微量锌的测定.  相似文献   

5.
测试了1×10-5mol/L5,5-二苯基-2,2-联唑(POOP)、反-1,2-双[2-(5-苯基唑基)]乙烯(POEOP)、4,4-双[2-(5-苯基唑基)]-1,1-联苯(POBOP)在含不同浓度卤代烃的1,4-二氧六环溶液中的荧光量子产率,讨论了荧光猝灭机理,计算出CH3I、PhI、PhBr对POEOP、POOP、POBOP的荧光猝灭速率常数.研究发现,卤代烃分子越小,卤原子核电荷数越高,其猝灭荧光能力越强  相似文献   

6.
研究了阳离子表面活性剂CTAB在临界胶束浓度(CMC) 前对1 - 芘丁酸(PBA) 和1 - 萘乙酸(NAA) 荧光光谱的影响, 观测到PBA和NAA激基缔合物的发光. 实验证明: CMC前CTAB 能够诱导PBA, NAA激基缔合物的形成. 这一结果为设计阴离子表面活性剂的荧光检测新方法提供了理论基础.  相似文献   

7.
TmxY1—xAl3(BO3)4晶体生长和光谱特性   总被引:1,自引:1,他引:0  
用K2Mo3O10-B2O3作助熔剂,采用缓慢降温自发成核的方法,生长了稀土四硼酸盐晶体TmxY1-xAl3(BO3)4(简称TYAB),晶体尺寸为8×6×5mm3.对所获得晶体进行X射线结构分析,表明TYAB晶体属三方晶系,晶胞参数a=9.237,c=7.192.测定了该晶体室温下的红外光谱、反射光谱、激发光谱及荧光光谱,当用261nm波长激发时,可产生345nm(3P0→3H4)蓝紫色及450nm(1D2→3H4)蓝绿色的荧光发射  相似文献   

8.
利用荧光光谱和透析平衡法研究了腺嘌呤、单磷酸腺苷(AMP)、三磷酸腺苷(ATP)与天花粉蛋白之间的相互作用。荧光光谱揭示腺嘌呤与天花粉蛋白结合后对其荧光强度影响较小,但使蛋白的荧光峰位红移,而AMP和ATP只引起蛋白荧光强度下降而不改变峰位。AMP,ATP引起的荧光强度下降包含着快慢两个过程。透析平衡法测得AMP,ATP与天花粉蛋白相互作用的结合常数分别为1.2×10 ̄(-1)mol/L和4.5×10 ̄(-5)mol/L,二者自由能之差为-2.26kJ/mol。  相似文献   

9.
研究了在阳离子表面活性剂溴化十六烷基三甲铵(CTMAB)存在下,钛与邻苯二酚紫(PV)显色反应的条件,结果表明,在PH=3.2的苯甲酸氢钾-盐酸缓冲溶液中,Ti(Ⅳ)与PV和CTMAB按照1:2:3的摩尔经形成绿色三元配合物,其最大吸收波长位于730nm,摩尔吸光系数为7.4×10^4L.mol^-1,钛在0.08-0.4μg/mL范围内符合比尔定律,检测限达0.02μg/mL.方法用于普碳钢和低  相似文献   

10.
研究了在混合表面剂CTMAB和OP存在下,9-(3,5-二溴)水杨基荧光酮吸光光度法测定微量锌的最佳显色条件及应用,试验结果表明,在PH9.80-10.40的硼硼-NaOH缓冲介质中,在CTMAB、OP存在下,Zn(Ⅱ)与DBSF形成下1:4配合物,表观摩尔吸光系数ε=1.3×10^5L·mol^-1·cmT^-1,配合物在常温下能稳2h,Zn(Ⅱ)量在0-8μg/25ml范围内符合比耳定律,用本  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.
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   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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