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1.
将KMnO4于200~1000℃范围内的不同温度下恒定温分解,制得K4Mn7O16.nH2O(n≈3),KMn8O16等不溶性锰酸盐,实验证明,这些锰酸盐对铁离子均有吸附作用,其中吸附量最大的吸附剂是在550℃下制备的KMn8O16在吸附除铁过程中存在着离子交换作用。  相似文献   

2.
文中从H2O2、KMnO4、NaClO三种氧化试剂,氧化条件的对比研究,提出酸性条件下KMnO4氧化玉米淀粉也是制备涂料成膜物质的可取途径之一  相似文献   

3.
藉高锰酸钾氧化双乙酰的化学发光反应测定抗坏血酸   总被引:2,自引:0,他引:2  
在KMnO2-双乙酰化学发光体系中加入抗坏血酸,KMnO4氧化抗坏血酸后产生的Mn^2+能够催化KMnO4与双乙酰的双化学发光反应。  相似文献   

4.
硫脲的化学发光分析研究   总被引:2,自引:0,他引:2       下载免费PDF全文
分别考察了钌( Ⅱ) - 联吡啶和硫脲在KMnO4 , Ce(SO4)2, KBrO3 , K2S2 O8 , I2 , KIO4 存在下的化学发光反应情况. 发现只有KMnO4 能氧化硫脲和钌( Ⅱ) - 联吡啶而发光. 考察了6 种表面活性剂对该体系的增敏效果( 吐温- 20 , 吐温- 40 , 吐温- 80 , 十六烷基三甲基溴化铵, 溴代十六烷吡啶, 十二烷基苯磺酸钠) . 发现十二烷基苯磺酸钠增敏效果最好. 体系的化学发光强度与硫脲的浓度在0-18~18μmol/L范围内呈良好的线性关系, 方法的检出限为0-18μmol/L.  相似文献   

5.
对高锰酸钾测定双氧水含量的分析方法的研究和改进   总被引:1,自引:0,他引:1  
研究KMnO4和双氧水在酸性条件下的自催化反应动力学,以及反应的诱导期与两种反应物浓度的关系,提出在各种浓度和KMnO4分析H2O2含量靠自身催化的分析方法,后的方法,适用浓度范围宽,反应速度快,滴定分析误差小。  相似文献   

6.
溶胶——凝胶法合成隐钾锰矿型MnO2   总被引:2,自引:0,他引:2  
用富马酸做还原剂,还原先导化合物KMnO4的淀粉产法制备了纯隐钾锰矿型MnO2。煅烧干凝胶的温度必须在500℃以下,最好是450℃,煅烧时间2h以上。  相似文献   

7.
文中从H2O2,KMnO4,NaClO三种氧化试剂,氧化条件的对比研究,提出酸性条件下KMnO4氧化玉米淀粉也是制备涂料成膜物质可取途径之一。  相似文献   

8.
用MnO4-/MnO412-间接电氧化体系对黄县油页岩的氧化条件及产物进行了研究。实验结果表明此过程可在室温下进行,并大大节省了KMnO4的消耗。氧化产物中的水溶酸主要由C6~C28的饱和脂肪族二元酸和C8~C31的饱和脂肪族一元酸组成。氧化过程中固体燃料残渣的FT-IR分析表明,油页岩有机质的脂肪族结构优先被氧化。  相似文献   

9.
文献「1」发现在强酸性条件下,KMnO4与H2O2反应体系中,KMnO4的褪色速度随H2O2初始浓度的增高而变慢,本文在综合考虑体系中各类复杂反应的基础上,从理论上对这一现象进下步加以研究,氦事求得由褪色速度表征的在对应动力关联方程,并对结果加以讨论。  相似文献   

10.
用MnO^-4/MnO^2-4间接电氧化体系对黄县油页岩的氧化条件及产物进行了研究。实验结果表明此过程可在室温下进行,并大大节省了KMnO4的消耗。氧化产物中的水溶酸主要由C6~C28的饱和脂肪族二元酸和C8~C31的饱和脂肪族一元酸组成。氧化过程中固体燃料残渣的FT-IR分析表明,油页岩有机质的脂肪族结构优先被氧化。  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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