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1.
基于室温下考马斯亮蓝可发射强而稳定的荧光,Mn2 能灵敏催化过氧化氢氧化考马斯亮蓝使体系的荧光增强,据此建立了Tween-80增敏过氧化氢氧化考马斯亮蓝催化荧光法测定痕量锰的新方法.其线性范围为0.01-2.00(ng/mL),工作曲线的回归方程为△F=2.306 100.6 C Mn2 (ng/mL),相关系数r=0.9989,检出限为7.5×10-12g/mL.本法成功用于自来水和江水中痕量锰(II)的测定.同时探讨了催化过氧化氢氧化考马斯亮蓝离子缔合物荧光反应机理.  相似文献   

2.
本文研究了锰(II)催化高碘酸钾氧化二苯胺磺酸钠和苯胺盐酸盐显色的新指示反应及其动力学条件,建立了动力学光度法测定痕量锰(II)的新方法,反应在醋酸-醋酸钠缓冲溶液中进行,并以邻菲罗啉和草酸钠作为活化剂,本法测锰(II)的灵敏度为4.6×10^-10g/ml,线性范围是0.5-2.4ng/ml,并对铝合金,纯铝和天然水样中的痕量锰进行了测定,获得满意的结果。  相似文献   

3.
本文研究了在NH3·H2O-NH4Cl介质中锰催化过氧化氢氧化苋菜红的褪色反应及其动力学条件,建立了测定痕量锰的新方法.该方法的检出限为5.6×10-4μg/mLMn,线性范围为0~1.8μg/25mL Mn,用于测定井水中痕量Mn,获得满意结果.  相似文献   

4.
研究了在pH9.7的介质中,利用Mn(2+)催化过氧化氢氧化水杨醛显色的指示反应,用萃取平衡控制反应时间及反应程度,通过测量500nm下水相的吸光度,建立了萃取催化光度法测定痕量锰的新方法方法的线性范围为0.020-0.20μg/ml,检出限为0.010μg/ml用于水样中痕量锰的测定,结果满意。  相似文献   

5.
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   

6.
实验研究发现:在pH=4.74的NaAc-HAc缓冲溶液介质中以氨三乙酸(NTA)作活化剂,Mn(Ⅱ)可以强烈地催化高碘酸钾氧化三溴偶氮氯膦褪色的反应。通过实验确定该反应体系的最佳条件,测定催化动力学参数及催化反应的表观活化能Ea′=37.73kJ/mol,表观速率常数为k′=8.85×10-4s-1,探讨了反应机理,确立反应的速率方程()lgA0A=K?Δt?CMn(∏),由此建立一个测定痕量锰的新方法。本方法的检测限是2.3×10-9g/mL,测定范围为2.3~10.0ng/mL。该法具有较好的选择性,用于枸杞、茶叶、环境水体试样中痕量锰的测定,结果令人满意  相似文献   

7.
在pH11.50的Na_2HPO_4-NaOH介质中,Mn(Ⅱ)能催化KIO_4氧化镁试剂。据此建立了催化动力学光度法测定痕量锰的新方法。方法的线性范围为0.1-1.0μg/25ml,灵敏度为4.0×10~(-9) g/ml。将方法用于铝合金及环境水样中锰的测定,结果满意。  相似文献   

8.
研究了在盐酸介质中,利用铁催化过氧化氢氧化溴百里酚蓝和罗丹明B褪色的指示反应及动力学条件,建立了催化动力学光度法测定痕量铁的新方法.该反应的最大吸收峰波长位于436 nm和600 nm处,线性范围为0.02~1.0μg/25mL,检出限为4.14×10-11g/L.本方法灵敏度高,体系稳定,具有较好的选择性,用于大米中痕量铁的测定.获得的结果较为满意.  相似文献   

9.
文章研究在硫酸介质中,利用铜催化过氧化氢氧化甲基橙和亮绿褪色的反应体系.探讨该褪色指示反应的最佳实验条件,在此基础上建立高灵敏度测定痕量铜的动力学分析新方法.通过对该反应催化体系和非催化体系吸光度的测定,确定该体系的最大吸收峰位于波长510 nm和640 nm处.工作曲线的线性范围:0.100~2.00μg/25mL.检出限:3.64×10-9g/mL,相对标准偏差:1.2%.本方法体系稳定,灵敏度高,选择性好,用于亳州道地药材中痕量铜的测定,结果较为满意.  相似文献   

10.
双波长双指示剂催化动力学光度法测定痕量亚硝酸根   总被引:1,自引:0,他引:1  
在磷酸介质中,利用亚硝酸根催化溴酸钾氧化亮绿和甲基橙褪色的指示反应,建立催化光度法测定痕量亚硝酸根的新方法.该反应的最大吸收峰在500 nm和640 nm处,线性范围1-11μg/25 mL,其检出限为2.82 × 10-10g/L,相对标准偏差0.05%.本方法灵敏度高,体系稳定,具有较好的选择性,用于自来水中痕量亚硝酸根的测定,结果较为满意.  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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