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1.
在0.10 mol·L~(-1) KH_2PO_4(pH 5.80)溶液中,用单扫示波极谱法可以得到一个灵敏的凯林甙(KHE)导数极谱波,其峰电位为-1.17V(SCE).峰电流与KHE的浓度在0.02~1.0μmol·L~(-1)范围内有线性关系.检测限为0.01μmol·L~(-1).用循环伏安法和常规脉冲极谱法等方法研究了极谱波的性质,测得还原电子数为2,吸附粒子为KHE中性分子,测得KHE在汞电极上的饱和吸附量为9.30×10~(-11)mol·Cm~(-2),每个KHE分子所占电极面积为1.79 nm~2,并提出了电极反应机理.  相似文献   

2.
研究了镉(Ⅱ)-铜铁试剂络合物的伏安行为,在0.15mol·L~(-1)NH_4Ac(pH6.7)、0.5 mmol·L~(-1)Cup溶液中,用单扫示波极谱得到一灵敏的Cd(Ⅱ)-Cup络合吸附波。峰电位E_P=-0.69 V(vs.SCE),峰电流与镉(Ⅱ)浓度在0.01~1.5μmol·L~(-1)范围内成正比,检出限为5.0mol·L~(-1)。用等摩尔系列法测得络合物的络合比为1:2,表观稳定常数为6.1×10~(11)。用线性扫描和循环伏安法、常规脉冲极谱等手段研究络合物电极反应机理。实验表明,该体系为可逆吸附波。  相似文献   

3.
在NaOH底液中,芬太尼(FT)在汞电极上有一灵敏的导数还原峰,峰电位为-1.45 V (vs.SCE).导数峰电流与FT浓度在1.0~20μmol·L~(-1)范围内成正比,最低检测限为0.5μmol·L~(-1).应用该方法测定了FT药物样品,结果满意.对FT在汞电极上的电化学行为特别是其吸附性进行了探讨.  相似文献   

4.
头孢氨苄(CEX)本身不具电活性,经NaOH溶液中加热降解后,在0.1mol·L~(-1)NaOH中得一灵敏的示波极谱还原峰,峰电位为-0.82 V(vs.SCE),峰电流与CEX浓度在0.1~1.5 μmol·L~(-1)范围内成线性关系,检出限为0.05μmol·L~(-1),相关系数为0.9999.用线性扫描与循环伏安法、脉冲极谱和恒电位电解法等研究体系的电化学行为.实验表明,体系属准可逆吸附.  相似文献   

5.
在混合磷酸盐溶液中,那可丁在汞电极上有一还原峰,其导数峰电位(SCE)E_(pc)=-1.75V.表面活性剂N(C_2H_5)_4Br对该峰有增敏作用.在单扫示波极谱上,峰电流与那可丁在0.06~1.0μmol·L~(-1)范围内成正比,最低检测限是0.04μmol·L~(-1).循环伏安法和常规脉冲极谱法等实验表明那可丁的还原属于反应物弱吸附的不可逆过程,还原电子数为2,吸附型体为中性分子.在此基础上提出了电极反应机理.  相似文献   

6.
考察了在NH_3-NH_4Cl底液中,那碎因的示波极谱行为。在pH 9.5的NH_3-NH_4Cl底液中该体系有一灵敏的导数极谱波,峰电位E=-1.51V(vs.SCE),峰电流i_p与那碎因浓度在0.10~7.0 μmol·L~(-1)范围内成正比,检测限为0.02 μmol·L~(-1)。用多种电化学方法确定那碎因在汞电极上的还原是属于反应物弱吸附的不可逆过程,吸附型体为中性分子,测得其在汞电极上的饱和吸附量Γ=0.781×10~(-10)mol·cm~(-2),电子转移数n=2,不可逆过程电子转移系数=0.56,扩散系数D=7.59×10~(-6)cm~2·s~(-1),电极反应速率常数k=8.32μm·s~(-1),并提出了电极反应机理。  相似文献   

7.
用单扫示波极谱仪,使钴(Ⅱ)在醋酸钠-醋酸-6-Br-BTAMB-硫酸羟胺底液中于-0.67V产生一灵敏的催化波,钴(Ⅱ)浓度在1.67×10~(-9)~1.67×10~(-7)mol·L~(-1)范围内与催化波峰高成良好的线性关系,检出限达6×10~(-10)mol·L~(-1).研究了催化波的形成条件及性质.测定了分子筛、生物制品及人发等样品中钴的含量.  相似文献   

8.
用单扫示波极谱法研究了2,4-二羟基二苯甲酮在不同浓度H2SO4介质中的极谱行为。实验表明,在0.2mol·L-1的H2SO4介质中其二阶导数峰电位为-1.01V(vs.SCE),峰电流与其浓度在2.5×10-8mol·L-1~1.0×10-6mol·L-1范围内有线性关系,线性方程为ip″(nA·s-2)=116.3+4.559×108c(mol·L-1),(r=0.9985)。循环伏安研究表明,该极谱波为吸附波。  相似文献   

9.
用线性扫描极谱法研究了雷公藤内酯酮在不同缓冲体系和氧化剂作用下的极谱催化波。实验表明,在pH=5.20的B-R缓冲溶液、0.1mol·L-1KCl和4.0×10-3mol·L-1H2O2体系中,雷公藤内酯酮极谱催化波的一阶导数峰电位为-0.97V(vs.SCE);一阶导数峰电流与浓度在1.3×10-8mol·L-1~1.3×10-7mol·L-1范围内有较好的线性关系,相关系数为0.9912。初步讨论了电极反应机理。  相似文献   

10.
邻菲罗啉的电化学性质研究   总被引:1,自引:0,他引:1  
0.5 mol·L-1的一氯乙酸和0.1 g·L-1的十二烷基磺酸钠溶液中,邻菲啰啉有一灵敏极谱峰,其峰电位是-0.75 V(vs.SCE).峰电流与邻菲啰啉的浓度在4.0×10-7~3.8×10-5mol·L-1范围内呈线性关系(r=0.998 5),检测下限为2.0×10-7mol·L-1.利用线性扫描极谱法和循环伏安法研究了邻菲啰啉的电化学性质.  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.
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   

18.
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   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
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