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1.
盐酸胺碘酮等三种含碘药物的光化学—化学发光法测定   总被引:3,自引:1,他引:3  
应用碘离子-鲁米诺体系的光化学-化学发光法测定盐酸胺碘酮、胆影葡胺和泛影葡胺三种含碘有机药物,方法简单、快速,I^-离子含量在2×10^-5~4×10^-4mol/L范围内与化学发光强度呈良好线性关系。三种药物样品测定的相对标准偏差均小于5%,回收率为94.94%-99.94%。  相似文献   

2.
痕量铁的化学发光法测定   总被引:1,自引:0,他引:1  
基于痕量Fe(3+)离子对溶解氧在碱性介质中氧化鲁米诺的反应具有催化作用,提出一种测定药物和饮用水中铁的化学发光法。铜试剂可作为增敏剂和Cu ̄(2+)离子的掩蔽剂.Fe ̄(3+)离子的含量在1.0~10.0ng·ml ̄(-1)内与化学发光强度成正比关系。本方法简便易行,检测限为1.4×10 ̄(-10)g·ml ̄(-1),相对标准偏差为1.6%和2.8%,回收率为94.0%和96.5%。  相似文献   

3.
钾铵离子选择电极的研制及其在土壤肥料分析中的应用   总被引:3,自引:0,他引:3  
以亚戊基双(4'-苯并15-冠-5)为中性载体,制得对K ̄+、具有相近响应的PVC膜离子选择性电极。Nernst线性响应范围1×10 ̄(-1)~8×10 ̄(-5)mol/L;响应斜率为53mV/PM;对Li ̄+、Na ̄+、Ca ̄(2+)、Mg ̄(2+)、Ba ̄(2+)的选择性系数分别为6×10 ̄(-5),5×10 ̄(-3),3×10 ̄(-4),4×10 ̄(-4),8×10 ̄(-4)。用本电极可快速测出土壤肥料中速效氮、钾的含量。  相似文献   

4.
研究5-Br-PADN与铁(Ⅲ)的显色反应,在pH9.0~9.4范围内,当有10%SDS存在时,铁(Ⅲ)与5-Br-PADN形成1:4的稳定配合物。λ_(max)为534nm,ε为5.13×10 ̄4L·mol ̄(-1)·cm ̄(-1),铁(Ⅲ)浓度在0~12.5×10 ̄(-4)g/L范围内符合Beer定律,用双峰双波长法测定茶叶中痕量铁(Ⅲ),结果满意。  相似文献   

5.
研究了文题体系的萃取机理。结果表明,初浓度为1.130×10 ̄(-2)mol/L的β-萘磺酸与初浓度范围为(1.451~4.135)×10 ̄(-2)mol/L的三辛胺在达到萃取平衡后,以1:1摩尔比缔合成胺盐萃合物;反应平衡常数K=5.00kL/mol;反应焓变。对β-萘磺酸之类的有机芳族磺酸来说,三辛胺是一种高效萃取剂。  相似文献   

6.
本文报道了亚硝酸根离子可以对Ce(Ⅳ)-罗丹明B化学发光体系产生抑制作用的实验事实,建立了测定痕量亚硝酸根离子的化学发光新方法.检出限为1.4×10-8mol/L;线性范围为1.0×10-7~4.0×10-5mol/L.用于实际水样中亚硝酸根离子的测定,结果满意.  相似文献   

7.
离子选择电极法测定蔗糖中Cu^2+含量的研究   总被引:2,自引:0,他引:2  
采用离子选择电极法测定蔗糖中铜的含量。方法简便、快速准确。标准曲线线性范围1.00×10^-6 ̄1.00×10^-4mol/L,平均回收率101.5%,RSD=2.4%(N=4)。  相似文献   

8.
羟基铬交联蒙脱土的制备及物化性能的研究   总被引:4,自引:0,他引:4  
本文以钠型蒙脱土(Na-Mt)为原料,以羟基铬聚合阳离子为交联剂制备出羟基铬交联蒙脱土(Cr-Mt)并对其物化性能进行研究。结果表明Cr-Mt的物化性能优于Na-Mt,d_(001)值1.6~1.9nm,比表面积80~190m ̄2·g ̄(-1),1.8~5.0nm的孔约占半数以上,表面总酸量为6.1×10 ̄(-4)~6.5×10 ̄(-4)mol·g ̄(-1)、阳离子交换量在9.0×10 ̄(-3)~42×10 ̄(-3)mol/100g样,但其热稳定性有待进一步提问。  相似文献   

9.
利用I ̄-、SCN ̄-都对Ce(Ⅳ)与As(Ⅲ)的氧化还原反应具有催化作用的特点,动力学荧光法测定I ̄-、SCN ̄-含量。又利用SCN ̄-时上述氧化还原反应的催化活性在一定条件下会失去的特点,选择性测定I ̄-,进尔计算出SCN ̄-的含量,测定I ̄-、SCN ̄-的线性范围分别为6.0×10 ̄(-4)~6.0×10 ̄(-3)、6.9×10 ̄(-2)~1.4mg/L.水样回收率分别为85%~110%和88%~117%。  相似文献   

10.
本文研究了邻菲罗啉氮氧化物-铜(Ⅱ)-过氧化氢化学发光体系的最佳反应条件,拟定了新的化学发光测定痕量铜的方法。本方法检出限为7.9×10 ̄(-9)mol/L,线性响应的浓度范围为1.6×10 ̄(-8)~1.6×10 ̄(-6)mol/L。考察了共存离子的干扰情况,用于铜精矿、茶叶及发样中铜的测定获得满意结果。本文还探讨了该体系化学发光的可能机理。  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.
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   

14.
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   

15.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

16.
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   

17.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

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