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1.
研究了牛血红蛋白(Hemoglobin,Hb)作为过氧化物模拟酶催化过氧化氢氧化偶氮胂Ⅲ(Arsenazo Ⅲ)褪色反应的催化特性和反应条件.结果表明:该催化反应体系在pH 4.0的HAc-NaAc缓冲溶液中、最大吸收波长536 nm处,褪色程度ΔA与H2O2的浓度之间具有线性关系,从而建立了测定H2O2的新方法.该方法的线性范围为1.03×10-5~2.58×10-4 mol·L-1,表观摩尔吸光系数为2.46×103 L·mol-1·cm-1.该方法用于消毒水中过氧化氢的测定,加标回收率为95.6%~106.1%.  相似文献   

2.
化学发光微流动注射芯片检测雨水中的过氧化氢   总被引:1,自引:0,他引:1  
基于在聚甲基丙烯酸甲酯(PMMA)材料上利用激光雕刻微流动注射通道和控制时间进样的模式,并将分离系统(离子交换树脂)引入到微流动注射系统中,结合luminol Co2 H2O2化学发光体系,建立了化学发光微流动注射芯片在线测定过氧化氢的方法.结果表明,采用该方法测定H2O2的线性范围为1×10-4~2×10-7mol/L,检出限为9 5×10-8mol/L,相对标准偏差RSD=2 9%(c=1×10-5mol/L,n=11).与常规的流动注射化学发光分析法相比,该芯片具有简单、操作方便、灵敏度高、分析速度快、尤其是耗样量少等特点,已应用于雨水中过氧化氢的测定.  相似文献   

3.
建立一种测定蔬菜水果中过氧化氢酶活性的新方法.在过氧化氢中加入过氧化氢酶分解部分过氧化氢,剩余的过氧化氢在酸性条件下与二价铁离子反应,产生的羟自由基与水杨酸反应生成紫色物质,该紫色物质最大吸收波长为510 nm,通过测定该物质含量来计算过氧化氢酶活性.结果表明:最佳反应条件为1m L p H=1的硫酸、4 m L硫酸亚铁溶液(1×10-3mol/L)、1m L过氧化氢溶液(0.003%)、2 m L水杨酸溶液(1×10-2mol/L),在40℃下反应10 min为最佳反应条件.测定的五种蔬菜水果中过氧化氢酶活性:土豆的过氧化氢酶的活性为4.96(μg/min);黄瓜的过氧化氢酶的活性为1.05(μg/min).  相似文献   

4.
茜素红褪色法测定血红蛋白   总被引:1,自引:1,他引:0  
在碱性介质中,H2O2产生的羟自由基可以氧化茜素红使之褪色,而过氧化物模拟酶--血红蛋白能够加速茜素红的褪色程度.基于血红蛋白对H2O2氧化茜素红体系的催化作用,建立了一种方便、快捷、灵敏的测定血红蛋白的催化动力学新方法.探讨了测定血红蛋白的最佳条件和干扰情况.该方法测定的线性范围为1.5×10-9~5.0×10-8mol/L,方法的检出限为6.0×10-10 mol/L,表观摩尔吸光系数为3.4×106 L·mol-1 ·cm-1 .该方法已成功地应用于动物血液中血红蛋白含量的测定,结果满意.  相似文献   

5.
将L-半胱氨酸电聚合于金电极表面,通过静电作用和共价结合,吸附带负电荷的纳米金(nano-Au),最后再利用纳米金吸附固定过氧化物酶(HRP),制备了一种新型层层自组装的电流型过氧化氢(H2O2)传感器.采用交流阻抗和计时电流法对该传感器的性能进行了详细研究.实验表明,该传感器增加了酶的吸附量,响应快、稳定性好,对H2O2表现出良好的响应特性.在0.1 mol/L PBS(pH值6.5)缓冲溶液中,电位为0.3 V的实验条件下,该传感器对H2O2检测范围为3.5×10-6~5.9×10-3 mol/L,检测下限为9.6×10-7 mol/L(S/N=3).  相似文献   

6.
本文报道以褐藻酸钙-过氧化物酶为固定相测定过氧化氢化学发光光导纤维探头.在pH10.2,10-3mol/l鲁米诺溶液中,过氧化氢在5×10-7- 1×10-3mol/l之间成线性关系.方法检出限为 3.2× 10-7mol/l H2O2.  相似文献   

7.
基于对乙酰氨基酚对鲁米诺-过氧化氢-辣根过氧化物酶(luminol-H2O2-HRP)体系的增强作用,建立了静态注射化学发光测定痕量对乙酰氨基酚的新方法,并对体系pH值、发光底物浓度等条件进行优化.通过对比不同混合溶液的紫外吸收光谱以及化学发光光谱,对该体系可能的发光机理进行了初步的探讨.结果发现,对乙酰氨基酚在4.0×10-4~7.5×10-3mol/L浓度范围内其增强发光值的对数与浓度呈良好的线性关系.对3.2×10-3mol/L的对乙酰氨基酚进行10次平行测定,其相对标准偏差为1.68%(n=10);检测限为1.6×10-4mol/L;回收率为95.0%~103.0%.对乙酰氨基酚的加入改变了luminol-H2O2-HRP体系中激发态的产生速率,从而使发光信号增强.  相似文献   

8.
制备了醋酸纤维素(CA)/普鲁士蓝(PB)复合膜修饰玻碳电极(CA/PB/GCE),用于过氧化氢(H2O2)检测.该修饰电极在中性缓冲液中对H2O2表现出良好的催化响应.0.05mol/L的PBS缓冲液中(pH7.0,0.1mol/LKCl作为支持电解质),在-0.2V的恒定电势下,使用该修饰电极采用时间电流法测定不同浓度的H2O2,在1.0×10-5~2.5×10-4mol/L的浓度范围内,响应电流和H2O2浓度间呈现出良好的线性关系,线性相关系数0.9994,检出限达2.2×10-6mol/L(信噪比为3),灵敏度为190mA·L·cm-2·mol-1.此外,该电极还表现出良好的操作稳定性.  相似文献   

9.
痕量间苯二酚的B-Z振荡反应动力学测定   总被引:1,自引:0,他引:1  
研究了在封闭体系中B Z振荡反应测定间苯二酚的条件 ,建立了测定痕量间苯二酚的新方法 .当 [KBrO3]=0 2 5mol/L ,[CH2 (COOH) 2 ]=0 5mol/L ,[Ce(SO4 ) 2 ]=0 0 4mol/L ,[H2 SO4 ]=0 8mol/L时 ,间苯二酚在 6 5×10 - 7mol/L~ 1 0× 10 - 5mol/L范围内 ,浓度与振幅改变值ΔA呈线性关系 ,检出限为 6 0× 10 - 7mol/L .用于废水中间苯二酚的测定 ,回收率为 99% .  相似文献   

10.
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   

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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