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1.
以簇合物[Mo3O2(CH3COO)6(H2O)3]Br2·2H2O和联苯二胺为原料,在乙醇溶剂中通过置换反应合成出新的三角三核钼簇合物,经紫外光谱分析、红外光谱分析、核磁共振谱分析、元素分析确定该簇合物的组成为[Mo3O2(CH3COO)6(H2O)(NHC6H4C6H4NH2·2H+)2]Br4·10H2O,并确定了该簇合物的结构.  相似文献   

2.
在 p H≈ 6.5及稀土盐 Gd Cl3 · 6H2 O或 Ce( NO3 ) 3 · 6H2 O的存在下 ,Na2 WO4· 2 H2 O与Na As O2 及 Co( NO3 ) 2 · 6H2 O反应 ,得到了夹层型杂多钨酸盐 N( CH3 ) 4 Na6[Na3 {Co( H2 O) }2 WO( H2 O) ( As W9O3 3 ) 2 ]· 35 H2 O单晶 ,用 X射线单晶衍射法及元素分析确定了其结构 ,晶胞参数为 :a=1 .395 ( 1 8) nm,b=1 .90 ( 2 ) nm,c=2 .2 9( 3) nm,α=1 0 2 .3( 4 )°,β=94.7( 3)°,γ=1 0 5 .3( 3)°,V=5 .65 6( 1 2 5 ) nm3 ,Z=2 ,空间群 Pī,R1=0 .0 60 0 ,w R2 =0 .1 2 0 7( I>2σ)。[Na3 {Co( H2 O) }2 WO( H2 O) ( As W9O3 3 ) 2 ]7-具有 C2 v对称性 ,Co2 +的配位数均为 5 .对题示化合物进行了 IR,UV- Vis表征 ,讨论了其形成条件  相似文献   

3.
利用酯基锡与缺位Keggin结构阴离子SiW9O10-34反应,合成了6种新的杂多阴离子有机金属配合物M4H3[(R'OOCCHR"CH2Sn)3(SiW9O37)]·xH2O(M=K+,(CH3)4N+;R'=CH3,CH3CH2;R"=H,CH3;x=6~12).通过元素分析、IR光谱、1H NMR、紫外电子光谱、循环伏安和TGA-DSC热分析等测试手段对标题配合物进行了表征和性质研究,确定该系列化合物为α-Keggin型三取代酯基锡杂多配合物.  相似文献   

4.
无机-有机杂化钼磷、钒钼磷多酸化合物的合成与结构   总被引:12,自引:5,他引:7  
通过对V2 O5 ,Na2 MoO4·2H2 O ,HF ,Ni(NO3) 2 ·6H2 O ,H3PO4和吡啶体系水热反应的研究 ,合成并表征了无机 -有机杂多酸化合物 [C5 H6 N] 3[C5 H5 N][PMo12 O40 ] ( 1 ) ,[C5 H6 N] 4[PVMo11O40 ] ( 2 )和 [C5 H6 N] 4[HPV2 Mo10 O40 ] ( 3 ) .化合物( 1 )属单斜晶系 ,C/ 2c空间群 ,a =2 .1 867( 6)nm ,b =1 .3 978( 4)nm ,c =1 .663 3( 3 )nm ,β =1 0 5.73 ( 1 0 )°,V =4 .893nm3,R =0 .0 60 4 ,Z =4 ;化合物 ( 2 )属单斜晶系 ,C/ 2c空间群 ,a =2 .1 858( 4)nm ,b =1 .3 971 ( 3 )nm ,c =1 .663 5( 3 )nm ,β =1 0 5.83 ( 3 )°,V =4 .8873 ( 1 7)nm3,Z =4 ,R =0 .0 4 63 ;化合物 ( 3 )属单斜晶系 ,P2 1n空间群 ,a =1 .1 1 2 2 ( 2 )nm ,b =1 .94 1 2 ( 3 )nm ,c=1 .2 4 84 ( 3 )nm ,β =99.89( 3 )°,V =2 .6565( 9)nm3,Z =2 ,R =0 .0 690 .  相似文献   

5.
利用酯基锡与缺位Keggin结构阴离子SiW9O10-34反应,合成了6种新的杂多阴离子有机金属配合物M4H3[(R′OOCCHR″CH2Sn)3(SiW9O37)]·xH2O(M=K+,(CH3)4N+;R′=CH3,CH3CH2;R″=H,CH3;x=6~12).通过元素分析、IR光谱、1HNMR、紫外电子光谱、循环伏安和TGA-DSC热分析等测试手段对标题配合物进行了表征和性质研究,确定该系列化合物为α-Keggin型三取代酯基锡杂多配合物.  相似文献   

6.
介绍了稀土金属离子YⅢ 与一系列氨基多羧酸类配体形成配合物的合成及分子结构和晶体结构 ,并讨论了这些配合物的配位规律及形成原因 .发现具有 0 .10 4nm离子半径和d0 电子结构的稀土金属YⅢ离子一般情况下与氨基多羧酸类配体形成九配位结构的配合物 ,如K3 [YⅢ(nta) 2 (H2 O) ]·6H2 O(nta =氨三乙酸 ) ,Na[YⅢ(edta) (H2 O) 3 ]·5H2 O(edta =乙二胺四乙酸 ) ,K2 [YⅢ(dtpa) (H2 O) ]·7H2 O(dtpa =二乙三胺五乙酸 ) ,K4[YⅢ2 (Httha) 2 ]·14H2 O(ttha =三乙四胺六乙酸 )和 (NH4) 2 [YⅢ(NH4ttha) ]·5H2 O等 ,但与具有一定刚性的环己烷环的cydta(=反式 1,2 环己二胺四乙酸 )配体却形成了八配位NH4[YⅢ(cydta)(H2 O) 2 ]·4 .5H2 O配合物 .另外 (NH4) 2 [YⅢ(NH4ttha) ]·5H2 O配合物中具有可用于修饰的未配位的自由羧酸基 ( CH2 COO-) .  相似文献   

7.
多金属氧酸盐纳米粒子修饰电极的制备及电催化研究   总被引:10,自引:11,他引:10  
通过溶胶 -凝胶技术首次将有机 -无机杂化的多金属氧酸盐纳米粒子 [(CH3) 4 N] 6 P2 Mo18O6 2 ·9H2 O修饰在蜡浸石墨电极的表面 ,并研究了该纳米粒子修饰电极的电化学行为和电催化行为 .不仅探索了一种更好的多金属氧酸盐修饰剂 ,而且为研究其他纳米粒子的电化学行为提供了一种简单而实用的方法 .  相似文献   

8.
通过NiSO4·6H2O与4,4'-联吡啶在H2O-CH3OH混合溶液中反应,制备了配位聚合物[Ni(4,4′-bpy)(H2O)4]·(SO42-)·(CH3OH)·(H2O),并使用X射线单晶衍射技术对其结构进行了表征.此配合物含有三种分别沿[100]、[010]、[110]方向排列的无限长链,并通过其配位水分子与位于层间位置的SO42-形成氢键而连接成为超分子结构.  相似文献   

9.
以TritonX-100/n-C10H21OH/H2O体系W/O微乳液为基础,分别以K8[Ce(Ⅳ)W10O33]·32H2O和Ba(NO3)2水溶液代替组分水制备W/O微乳液.然后将两种微乳液混和,得到淡黄色沉淀的Ba4[Ce(Ⅳ)W10O32]·24H2O纳米粒子.经电镜分析所得Ba4[Ce(Ⅳ)W10O33]·24H2O纳米粒子为粒径6 nm的圆球状颗粒.并用TG-DTA和Raman对该化合物进行了袁征.  相似文献   

10.
由CoCl2 ·6H2 O与KSCN和六次甲基四胺 (HMTA)反应得到超分子化合物 [Co(NCS) 2 ·(H2 O) 2 ·(HMTA) 2 ][Co(NCS) 2 ·(H2 O) 4]·(H2 O) 2 ,并测定了其晶体结构 .该化合物由 [Co(NCS) 2 ·(H2 O) 2 ·(HMTA) 2 ]、[Co(NCS) 2 ·(H2 O) 4]和H2 O三部分组成 ,每一个HMTA配体中仅有一个N原子与Co配位 ,剩余的三个N原子分别与 [Co(NCS) 2 ·(H2 O) 4]中的水及结晶H2 O分子之间形成氢键 .[Co(NCS) 2 ·(H2 O) 2 ·(HMTA) 2 ]和 [Co(NCS) 2 ·(H2 O) 4]之间通过NHO氢键连接成无限延伸的线性长链 ,链与链之间、链与结晶水之间通过不同形式的氢键构成三维结构的超分子  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.
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   

14.
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   

15.
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   

16.
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   

17.
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   

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.
The non-orthogonal localized molecular orbital(NOLMO)is the most localized representation of electronic degrees of freedom.As such,NOLMOs are thus potentially the most efficient for linear scaling calculations of electronic structures for large systems.However,direct ab initio calculations with NOLMO have not been fully implemented and widely used,partly because of the slow convergence issue in the optimization of NOLMO.We devel-  相似文献   

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