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1.
微量铝的富集分离方法研究   总被引:5,自引:0,他引:5  
本文提供了一种新的快速富集分离测定水中微量铝的方法,该法简便、快速、灵敏度高,检测限为2.0×10-9g/L.用于天然水中微量铝的测定取得满意结果。  相似文献   

2.
研究了用离子交换树脂相比色法测定微量钼的最佳条件。用此法测定了呼和浩特地区自来水和马奶酒中钼的含量,相对标准偏差分别为2.5%和3.1%,结果满意。  相似文献   

3.
关于用二甲酚橙测定铝曾有若干报导,但用于实际工作不多。鉴于二甲酚橙与铝反应的灵敏度较高,稳定性好,且可用EDTA掩蔽部分干扰元素,因此可改进其选择性。我们试图用甲基异丁酮——钽试剂一次萃取分离钢中的铁、钒、钼、钨、钛、铌锆等干扰元素,并用EDTA掩蔽部分干扰元素,以二甲酚橙测定钢中的微量铝,经过实践证明,用二甲酚橙测定钢中的微量铝亦可获良好的结果。  相似文献   

4.
在pH2.1的硫酸-2.96×10-6mol/L桑色素-0.172mol/L氯酸钾底液中,钼在-0.43V(SCE)有一灵敏的极谱催化波,可用于测定微量钼.线性范围1.04×10-9~2.50×10-8mol/L,检出限1.88×10-10mol/L. 极谱催化波法直接应用于三氧化钨光谱标样中微量相的测定,方法简便,准确可靠。  相似文献   

5.
采用微波消化测定动物组织中微量的铝。先用硝酸高压溶解,然后用石墨炉原子吸收测定。方法的检出限0.91ng/ml,线性范围0—1000ng/ml,其回收率为95.1%-104.7%.该方法简化了对动物组织中铝测定的消化,精密度高,检出限低。  相似文献   

6.
研究了荧光光度法测定微量钼的新方法.在0.04~0.24mol.L^-1的盐酸介质中,邻氟苯基荧光酮(O-FPF),溴化十六烷基三甲铵(CTMAB)和钼M0(Ⅵ)形成无荧光的三元配合物,从而导致体系的荧光熄灭,在激发波长λcm=365nm和发射波长λcm=529nm时,钼含量在0-3.0μg/25mL范围内,荧光熄灭值△F和钼浓度成正比.方法灵敏度高,检出限为2.0μg/L.用于水样中微量钼的测定,结果满意.  相似文献   

7.
探讨砷钼杂多酸的生成条件及用罗丹明6G─砷钼杂多酸分光光度法测定无机盐中微量砷的测定条件.  相似文献   

8.
中药甘草,陈皮及复方中微量钼的分析   总被引:3,自引:0,他引:3  
本工作作用谱催化法进行了中草药甘草、陈皮和一剂含13种单味药的治肺癌复方中微量钼的分析,结果表明,分析方法适合;煎剂中药物总浸出率约40%,钼的浸出率随机物而异,陈皮达54%,方剂为20%;方剂中钼含量甚高。  相似文献   

9.
研究了Cl-P204萃淋树脂分离高含量钼溶液中微量铼的性能和条件,建立了一种在高钼低铼下,树脂柱分离硫脲显色分光光度法测定微量铼的方法。  相似文献   

10.
本文研究了在混合显色剂(PF+PAN)的胶束体系中,利用掩蔽系数同时测定中草药中钼和铜的光度分析法.实验表明:在混合体系中,钼量在0~10μg,铜量在0~50μg的范围内符合比耳定律,ε′Mo=92×104,ε′Cu=15×104.该法用于中草药样品的分析,结果令人满意,回收率可达92%~111%.  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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