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1.
辣根过氧化物酶(HRP)催化H2O2氧化四甲基联苯胺(TMB)生成大分子聚合物并产生强烈的共振光散射,由此建立了操作简单快速、高灵敏度测定HRP的新方法. 探讨了酸度、TMB浓度、H2O2浓度、温度等对散射信号的影响. 在最佳实验条件下测定HRP的线性范围为1×10-7~1×10-6 g/L,最低检出限1.8×10-8 g/L.  相似文献   

2.
本文设计一种芯片三电极系统,以金盘电极为工作电极,金片电极为辅助电极,Ag/ AgCl电极为参比电极,以邻联茴香胺(ODA)和邻苯二胺(OPD)两种常见的底物体系建立了检测辣 根过氧化物酶(HRP)的方法。HRP能够催化H2O2氧化ODA和OPD,其氧化产物在芯片金电极上分 别于-0.23 V和-0.50 V(vs.Ag/AgCl)处产生一个灵敏的还原峰,峰电流随HRP浓度增加而增大。对 于 ODA-H2O2体系,测定游离 HRP 的范围是 5.0×10-7~1.0×10-5 g/mL,检出限为 1.0×10-7 g/mL (3σ)。对于 OPD-H2O2体系,测定游离 HRP 的线性范围是 1.0×10-8~1.0×10-4 g/mL,检出限为 1.0×10-9 g/mL(3σ)。  相似文献   

3.
提出了以二苯胺为底物的伏安酶联免疫分析新体系测定辣根过氧化物酶 (HRP)的方法 .通过线性扫描二阶导数极谱法测定 HRP催化 H2 O2 氧化二苯胺的产物 ,从而间接的测定 HRP的浓度 ,进而用于酶联免疫分析 .在 p H=8.5的 Britten-Robinson(BR)缓冲溶液中 ,二苯胺的氧化产物可以在 -0 .53V(vs.SCE)左右处产生一个灵敏的极谱还原峰 .在选定的最佳条件下 ,应用此峰测定 HRP的检测限可达 1 .0× 1 0 - 9g/m L,测定 HRP的线性范围是 4 .0× 1 0 - 9~ 2 .0× 1 0 - 7g/m L.另外 ,还推导了酶催化反应和电极还原反应方程式  相似文献   

4.
研究了铜(Ⅱ)催化H2O2氧化7-(5-羧基-1,3,4-三氮唑偶氮)-偶氮氯膦(CTACPA)的褪色反应,褪色反应程度与铜(Ⅱ)量在一定范围内呈线性关系,建立了测定痕量铜(Ⅱ)的催化动力学光度法.在pH 4.0的HAc-NaAc缓冲溶液中,褪色体系的最大吸收波长535 nm,铜(Ⅱ)的质量浓度在(0.004 ~0.2)μg/mL范围内符合线性关系.回归方程为△A=3.026 0ρ-7.24×10-3(ρ:μg/mL),相关系数r=0.999 4,检出限为2.90×10-10 g/mL.方法不经分离直接测定头发和河水中的痕量铜,测定结果与AAS法的测定值相符.  相似文献   

5.
流动注射化学发光法测定痕量钒(Ⅴ)   总被引:1,自引:0,他引:1  
基于在硫酸介质中钒(Ⅴ)与磷钼酸形成具有更强氧化性的磷钼钒杂多酸(HPA),而磷钼钒杂多酸可直接氧化碱性鲁米诺产生强的化学发光,并结合流动注射分析技术,建立了一种测定痕量钒的新方法.其线性范围为5 0×10-9~1 0×10-5g/mL,方法的检出限为1 0×10-9g/mL.测定2 0×10-7g/mL的钒,11次连续测定的相对标准偏差为2.2%.方法已用于水样中痕量钒的测定.  相似文献   

6.
研究了催化动力学褪色光度法测定痕量铜(Ⅱ)的新体系,反应介质为NH3·H2O-NH4Cl缓冲溶液(pH=10.0),催化体系为痕量Cu(Ⅱ)催化H2O2氧化茜素的褪色反应.考察了反应体系的适宜条件、动力学性质及28种干扰离子的影响,建立了一种催化动力学光度法测定痕量铜的新指示反应.本法的线性范围为0~1.2×10-7 g/mL,其灵敏度远远高于普通光度法,检出极限为1.76×10-10g/mL,可应用于农产品和蒙药中铜的测定,相对标准偏差为1.1%~3.2%.  相似文献   

7.
高效液相色谱化学发光法测定淫羊藿甙   总被引:1,自引:0,他引:1  
在碱性条件下,研究了淫羊藿甙与Co(Ⅱ)形成的1∶1配合物催化鲁米诺-H2O2体系产生化学发光.在此基础上建立了反相高效液相色谱(RP-HPLC)分离柱后化学发光检测淫羊藿甙的新方法,并成功应用于安神补脑液中淫羊藿甙的测定.方法在0.5~20μg/mL范围内与化学发光强度呈良好的线性关系,相关系数为0.9986,检出限为2×10-7g/mL(3σ).对2×10-6g/mL淫羊藿甙平行测定11次,其相对标准偏差为4.5%.  相似文献   

8.
酶解-水扬酸盐光度法测定牛奶中的尿素   总被引:9,自引:1,他引:8  
提出一种测定牛奶中尿素的新方法 ,以刀豆粉提取液作脲酶催化尿素水解产生氨 ,氨由水扬酸盐光度法测定 .本法中有色化合物的最大吸收波长 70 0nm ,表观摩尔吸光系数ε 70 0 =1.3×10 4 mol-1.L .cm - 1,线性范围 0~ 0 .8μgN/mL ,,检出限 1.1× 10 -6gN/L  相似文献   

9.
在pH 4.8的HAc-NaAc缓冲溶液介质中,利用痕量铬(Ⅵ)催化H2O2氧化次甲基蓝和罗丹明B褪色的指示反应,通过测量在555 nm和665 nm下催化体系和非催化体系吸光度的变化,建立双波长双指示剂催化动力学光度分析测定痕量铬(Ⅵ)的新方法.方法的线性范围为0.025~1.40μg/25mL,检出限为5.2 × 10-10g/mL.该法简单、灵敏度高、选择性好,用于废水中痕量铬(Ⅵ)的测定,结果满意.  相似文献   

10.
催化动力学光度法测定痕量铜   总被引:2,自引:0,他引:2  
在弱酸性介质中,痕量铜可强烈地催化过氧化氢氧化灿烂绿的褪色反应,从而建立了测定痕量铜的催化动力学光度分析新方法.在最佳实验条件下,本法的检出限为8.6×10-9g/mL,线性范围为(0.0-0.2) μg/mL, 用于实际水样中痕量铜的测定,结果令人满意.  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 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.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
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   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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.
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   

19.
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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