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1.
研究了用1-苯基-3-甲基-4-二氯乙酰基吡唑酮-5(PMDCP)和2,2′-联吡啶(Dipy)的氯仿溶液协同萃取钢(Ⅲ)、镨(Ⅲ)、钕(Ⅲ)、钆(Ⅲ)、钇(Ⅲ)、镝(Ⅲ)、镱(Ⅲ)和镥(Ⅲ)。用斜率法和固态协萃合物的元素分析确定了镧协萃合物的组成为La(PMDCP)_3·Dipy。计算了其半萃取pH值以及303K时的协萃常数,考查了固态协萃合物的红外、紫外吸收光谱以及热稳定性。  相似文献   

2.
钛-镁体系烯烃聚合催化剂中钛离子状态的EPR研究   总被引:1,自引:0,他引:1  
利用EPR法研究了MgCl_2-n-BuOH-SiCl_4-TiCl_4/Al(i-Bu)_3体系催化剂中钛离子的状态,发现催化剂体系中存在(Ⅰ)、(Ⅱ)、(Ⅲ)和(Ⅳ)四种类型的Ti~(3 )离子的顺磁物类,其EPR信号分别为g=1.99,g_Δ=1.97,g_Δ=1.95和g_Δ=1.88,前三者为处于不同畸变配体场中的非烷基化Ti~(3 )离子,在烯烃聚合中不起活性中心作用.带有Cl空配位的烷基化Ti~(3 )离子是活性的物类,但其中只有少部分呈弧立状态的(Ⅳ)型离子对EPR有贡献,大部分可能通过氯桥键合,在MgCl_2表面上形成聚集体或TiCl_3分散粒子而成为EPR无声的物类.  相似文献   

3.
应用位置灵敏探测和飞行时间技术,测量了Cq (q=1,2,3)离子与Ar原子碰撞反应中的转移电离截面与单电子俘获截面之比,并与DuBois的Heq (q=1,2)与Ar的实验结果进行比较.同时在玻尔的过垒模型基础上,给出进一步的定性解释。  相似文献   

4.
本文利用X射线单晶衍射方法测定了六元瓜环(Q[6])和对称四甲基取代六元瓜环(TMeQ[6])与钆(Ⅲ)离子形成的配合物的结构。结果表明,Q[6]-Gd(Ⅲ)离子和TMeQ[6]-Gd(Ⅲ)离子都形成1∶2的配合物,配合物通过氢键网络形成超分子链。  相似文献   

5.
偕胺肟合汞(Ⅱ)纤维对硫酸根离子吸附性能的研究   总被引:1,自引:0,他引:1  
以含偕胺肟基团的螯合纤维为原料,经Hg(NO3)2溶液化学处理,制得偕胺肟合汞(Ⅱ)纤维,研究了时间、温度、pH值和离子浓度等因素对偕胺肟合汞(Ⅱ)纤维吸附硫酸根离子性能的影响.并采用红外光谱仪和扫描电子显微镜对样品进行了表征.实验结果表明,偕胺肟合汞(Ⅱ)纤维对硫酸根离子具有较好的吸附能力,在反应时间为60min,温度为30℃,pH=4,硫酸根离子浓度为0.05mol/L时,最高吸附量可达1.740mmol/g,其吸附行为符合Langmuir等温吸附模型.  相似文献   

6.
对于无机物的定量结构与性质相关性 (QSPR)研究的实例不多[1].本文根据辛厚文等人的键参数拓扑指数[2 ]提出离子特征拓扑指数 (It) ,用于镧系元素 (Ln)的 3价离子 (Ln3 )的 1 0种性质 (Pi)相关性研究 ,取得了令人满意的线性相关性 ,其中 8种性质的相关系数在 0 .99以上 .1 离子特征拓扑指数It辛厚文等人的键参数拓扑指数 (H11) [2 ]为 :H11={Σi[(1 Δi)PiQi] - 1} 2 (1 )式中“Σ”是对分子图中所有边 (键 )求和 ;Pi、Qi 为i边的两顶点 (原子 )的支化度 ;Δi 是i边两顶点原子的键参数之差 .对于某元素的离…  相似文献   

7.
研究了基于水杨醛缩碳酰胺合铜(Ⅱ)[Cu(Ⅱ)-SAU]、水杨醛缩碳酰胺合镍(Ⅱ)[Ni(Ⅱ)-SAU]的金属配合物为中性载体的阴离子选择性电极.实验结果表明:以水杨醛缩碳酰胺合铜(Ⅱ)[Cu(Ⅱ)-SAU]为中性载体的离子选择性电极对水杨酸根离子(Sal-)具有良好的电位响应特性,且呈现反Hofmeister行为,其选择性序列从大到小为:Sal-,ClO4-,I-,SCN-,NO2-,NO3-,Br-,SO24-,SO23-,Cl-.在pH=4·0的磷酸盐缓冲体系中该电极具有最佳的电位响应,在1·0×10-1~9·6×10-6mol/L浓度范围内呈近能斯特响应,斜率为-51·4mV/dec(25℃),检测下限为8·1×10-6mol/L.采用交流阻抗研究了电极的响应机理,并将电极用于样品分析,结果比较满意.  相似文献   

8.
本文研究了Fe(Ⅲ)、Zn(Ⅱ)、Ag(Ⅰ)的邻菲罗啉配离子与四苯硼酸根生成三元离子缔合配合物沉淀的pH条件,实验验证了金属—邻菲罗啉配离子与四苯硼酸根的缔合比。用系数比率法测定了Fe(Ⅲ)、Fe(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)、Cu(Ⅱ)、Zn(Ⅱ)、Cd(Ⅱ)、Ag(Ⅰ)的邻菲罗啉—四苯硼酸根三元配合物沉淀的溶度积Ksp,并对有关缔合性质进行了探讨。  相似文献   

9.
一、引言 前曾报导,硫酸和盐酸中的Mn(Ⅱ)能加速UO_2~(2 )和U(Ⅳ)在阳树脂中的扩散,Cu(Ⅱ)一氯合离子能改善UO_2~(2 )氯合阴离子的色谱峰,为系统研究金属络合阴离子的加速作用,本文以4NHCl为介质,分别加入Zn(Ⅱ),In(Ⅲ)Co(Ⅱ)和Cr(Ⅲ)为流洗剂以流洗U(Ⅵ),得出了某些规律性的结果。  相似文献   

10.
以N,N-二乙胺基和N-乙基咔唑为端基电子给体基团,利用4-溴-2-羟基苯乙酮分别与4-(N,N-二乙胺基)苯甲醛和N-乙基咔唑-3-醛缩合得到2种新型溴查尔酮衍生物氰离子探针(化合物Ⅰ和Ⅱ);利用核磁共振光谱仪对其鉴定,用紫外可见分光光度计和荧光光谱仪研究探针的光物理性质及其与氰离子的识别性质,并对其键合机理进行分析。结果表明:实验合成了氰离子探针,且对氰离子表现出明显的吸收和荧光光谱响应,原蓝光波段吸收峰降低,在乙腈中的荧光检测限分别是0.103μmol/L(Ⅰ)和0.002μmol/L(Ⅱ),吸收检测限分别为1.04μmol/L(Ⅰ)和0.12μmol/L(Ⅱ),化合物Ⅱ可以实现在水合环境中对氰离子的识别,其检测限为5.5μmol/L。键合机理分析表明,2种化合物与氰离子之间发生了典型的迈克尔反应。  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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