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1.
本文测定了Cu(Ⅱ)的三个四氮杂环十四烷二烯配合物CuL1Br2.2H2O,CuL2Br2.2H2O和CuL3.Br2.2H2O(L1代表5,4-二甲基-7,12-二苯基--1,4,8,11-四氮杂环十四烷-4,14-二烯;L2代表5,14-二甲基-7,12-二对氯苯基-1,4,8,11-四氮杂环十四烷-4,14-二烯;L3代表5,14-二甲基-7,12=-二甲氧苯基-1,4,8,11-四氮杂环十  相似文献   

2.
从(-)-α-蒎烯氧化制得的(+)-2-羟基蒎-3-酮[(+)-1],经还原得到的顺-(-)-和反-(-)-蒎烷-2,3-二醇[(-)-2和(-)-3];(+)-1与Grignard试剂反应制得的顾-3β-烃基蒎烷-2,3-二醇,烃基为甲基[(-)-4)、苯基[(+)-5]和苄基[(-)-6];以及自(+)-α-蒎烯制得的(-)-1的(-)N-(β-羟乙基)酮亚胺[(-)-7]。用2~7修饰LiAlH_4制成手性试剂LiAlH_2(?)P~*,并使之还原苯乙酮。从得到的产物α-苯乙醇的e. e. %值差别归纳出了有关这一类手性试剂的3个在结构上的要点。  相似文献   

3.
综合利用硅胶柱层析、Sephadex LH-20凝胶柱色谱、制备高效液相色谱等多种方法对红花栝楼种子进行分离纯化,运用现代波谱技术对得到的化合物进行结构鉴定,从中分离得到4个化合物,分别鉴定为7,24-二氧代-10α-葫芦烷-5,25-二烯-3β-醇(1)、葫芦烷-5,25-二烯-3β,24-二醇(2)、(反式)-11-甲氧基-11-氧代十一烷-2-烯酸(3)和(12S,13S,Z)-12-羟基十八烷基-9-烯-13-内酯(4).其中化合物1、2为新化合物,3为新的天然产物,4是首次从栝楼属植物中分离得到.  相似文献   

4.
以异丙醇为溶剂,异丙醇钠和二硫化碳反应生成异丙基黄原酸钠1,1未经纯化,向反应瓶中直接加入二氯乙酸四甲酯,制得2,2-双-(异丙基黄原酸基)乙酸甲酯2.2经过浓硫酸催化,得1,3,4,6-四硫杂戊搭烯-2,5-二酮3。整个过程操作简便,产率较高,是制备1,3,4,6-四硫杂戊搭烯3的简便方法。  相似文献   

5.
采用3-二甲氨基丙胺和间苯二甲酰氯为原料,合成二(3-二甲氨基丙基)间苯二甲酰胺,再分别与溴代正十二烷、溴代正十四烷和溴代正十六烷反应制得3种含酰胺键的Gemini阳离子表面活性剂(C12-N-C12、C14-N-C14、C16-N-C16).采用IR、1 H-NMR、元素分析表征了其结构.测定其临界胶束浓度(CMC)分别为5.96×10-4、1.03×10-4、6.25×10-5 mol·L-1;表面张力(γCMC)分别为40.83、38.76、38.08 mN·m-1;Krafft点分别为0、0、12℃,并研究了其乳化性、泡沫性质.  相似文献   

6.
采用合成时环境友好,在四氢呋喃中溶解性良好的二甲基苯酚钾作助引发剂,正丁基锂为引发剂、二甲苯为溶剂兼作链转移剂、2G为极性调节剂对二烯烃阴离子调聚进行了研究。考察了不同D-ROK/n—BuLi对聚合物的特性粘度、分子量、分子量分布及微观结构的影响关系。制得的液体聚丁烯和聚异戊二烯可用作绿色涂料的原料。  相似文献   

7.
酞菁铁—表面活性剂薄膜修饰电极及其催化性能   总被引:1,自引:0,他引:1  
将酞菁铁(FePc)掺入阳离子表面活性剂双十二烷基二甲基溴化铵(DDAB)的氧仿溶液,并涂布于热解石墨电极表面,待氯仿挥发后即制得FePc-DDAB薄膜电极,循环伏安实验表明,在KBr溶液中该薄膜电极有2对还原氧化峰,第1对峰的Epcl=-0.64V,Epal=-0.29V(vs.SCE)第2对峰的Epc2=-1.04V,Epa2=-0.94V着重探讨了第2对峰的电化学行为,估计了该体系的电化学参  相似文献   

8.
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   

9.
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   

10.
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   

11.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

12.
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   

13.
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   

14.
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   

15.
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   

16.
17.
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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