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1.
首次合成了镧(La)、镨(Pr)、钕(Nd)、钐(Sm)、钆(Gd)的果糖-高氯酸固体配合物以及La,Pr,Nd,Sm,Gd和Eu(铕)的硼酸-果糖配合物.利用化学分析,IR,1HNMR,UV和热谱等物理化学手段对这两系列共11个配合物的组成和成键情况进行了表征,并对它们的某些物理化学性质进行了研究.结果表明:稀土-果糖-高氯酸配合物的组成为:RE3(C6H11O6)5(OH)2(ClO4)23H2O(RE=La,Pr,Nd,Sm,Gd);稀土-果糖-硼酸配合物的组成为:RE(C6H12O8B)2Cl2CH3OH,(RE=La,Pr,Nd,Sm,Eu,Gd).  相似文献   

2.
稀土氯化物与咪唑配合物的热分解研究   总被引:5,自引:0,他引:5  
采用TG-DTG,在不同气氛(O2气氛、N2气氛)、不同升温速率条件下,对五种氯化稀土咪唑配合物RE(C3H4N2)nCl3·0.5CH3OH·2HCl·mH2O(RE=La,Nd,Sm,n=2;RE=Gd,Y,n=2.5)的热失重行为进行了研究,推测了各配合物的热分解过程;应用Kissinger公式计算了配合物中咪唑分解的表观活化能,并用DSC对氯化稀土(La,Nd)咪唑配合物进行了分析  相似文献   

3.
采用半微量相平衡方法研究了LaCl3·3H2O-B15C5-CH3CN三元体系在25℃时的溶解度,测定了各饱和溶液的折光率。该体系在25℃生成一种化学计量的三元配合物:LaCl3·B15C5·3H2O-CH3CN。经分离、洗涤制得了固态配合物,分别在80%H2SO4与98%H2SO4干燥器中干燥王恒重,经化学分析确定配合物的组成为:LaCl3·B15C5·3H2O与LaCl3·B15C5。用IR,DTG,TG,DSC以及x-射线衍射分析研究了配合物的组成与性质。  相似文献   

4.
合成了含有Cl-桥联配体的两个新的双核配合物:Cu2(ampy)2Cl4·1/2C2H5OH(ampy=α-氨基吡啶)和Cu2[N,N’bis(ampy)-bzac(H2O)]Cl4·C2H5OH(bzac=苯甲酰丙酮).通过元素分析、IR、ESR和室温磁化率表征,测定了这两个配合物的变温磁化率(4~300K),其数值用最小二乘法与从自旋Hamiltonian算符导出的磁化率理论曲线拟合很好;求得了交换积分,对于配合物Cu2(ampy)2Cl4·1/2C2H5OH,J=-4.76Cm-2;对于Cu2[N,N’bis(ampy)-bzac(H2O)]Cl4·C2H5OH,J=-4.72cm-2,表明两个配合物中Cu(Ⅱ)-Cu(Ⅱ)核间有反铁磁相互作用.  相似文献   

5.
通过2价Sm(C9H7)2与I2,(C6H5CO2)2,[(C2H5)2NCS2]2作用,研究了在四氢呋喃溶液中Sm(C9H7)2断裂I-I,O-O,S-S键的反应,得到了3个新的、对空气和湿气敏感的3价稀土金属有机配合物。产物经元素分析、红外光谱、质谱等鉴定,推测其组成结构分别为(C9H7)2SmI(THF)(A)、[(C9H7)2Sm((C6H5CO2)]2(B),{(C9H7)2Sm[(C2  相似文献   

6.
合成了稀土土离子(La^3+,Nd^3+,Eu^3+,Gd^3+,Tb^3+,Er^3+)与吡啶乙酸内盐(C5H5N^+CH2CO^-2,pyb)及,2,2‘-联吡啶的三元配合物。通过元素分析,红外光谱等测试手术,确定配合物的组成为RE2(bpy)5(pyb)4(ClO4)6.5H2O。测定了Eu^3+配合物的晶体结构,属三斜晶系。  相似文献   

7.
本文合成了一系列烷基芳基不对称亚砜R1-C6H4-SO-R2(R1=CH3,C(CH3)3;R2=C2H5,C4H9,C6H13,CH2CH(C2H5)C4H9),并且以之为配体(L)和硝酸铀酰反应,制备了一系列硝酸铀酰配合物UO2L2(NO3)2,通过元素分析、摩尔电导、红外光谱,研究了配合物的组成、结构和性质,并测定了配合物[UO2(TBSO)2(NO3)2]的晶体结构。  相似文献   

8.
以2-甲基烯丙基氯化镁与无水稀土氯化物低温下反应,得到含镁2-甲基烯丙基稀土配合物(Ln(C4H7)2(Mg2Cl5(THF)4)。该配合物与环戊二烯或吡咯进行配体取代反应,分别得到两个系列的含环戊二烯基(C5H5)或吡咯基(C4H4N)的异核混配型稀土烯丙基配合物(Ln2(C5H5)3(C4H7)Mg3Cl8(THF)6,Ln2(C4H4N)3(C4H7)Mg3Cl8(THF)6(THF)6(L  相似文献   

9.
合成了稀土离子(La3+,Nd3+,Eu3+,Gd3+,Tb3+,Er3+)与吡啶乙酸内盐(C5H5N+CH2CO2-,pyb)及2,2′-联吡啶(bpy)的三元配合物.通过元素分析、红外光谱等测试手段,确定配合物的组成为RE2(bpy)5(pyb)4(ClO4)6·5H2O.测定了Eu3+配合物的晶体结构,属三斜晶系.通过f-f超灵敏跃迁光谱及荧光光谱讨论了配合物化学键的离子性特点.  相似文献   

10.
报道了8种2-[(取代苯胺基)羰基]苯甲酸与Sm(Ⅲ)配合物Sm(P)3.3H2O[其中P=2-(COO)C6H4CONHC6H5-nXn,X=H,2-Cl,4Br,2-CH3,3-NO2,2-OCH3,2,4-二氯,3-OH,n=1,2]的合成,并用元素分析、红外光谱、电子反射光谱、热重分析进行了表征。结果证明了配位是通过羰酸羟基原子和酰胺羰基氧原子进行的,含3分子配位水。  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.
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   

13.
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   

14.
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   

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.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

17.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

18.
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   

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

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