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1.
用脂肪醇与环氯丙烷在碱性条件下合成了季铵盐型阳离子表面活性剂.所得产品用X-射线单晶衍射法测定了晶体结构.该化合物采用双分子层结构,整个化合物由交叉的线性烷基链、季胺阳离子和溴离子组成.用偏光显微镜、差示扫描量热(DSC)技术研究了其液晶行为,证明该化合物为近晶相热致液晶.  相似文献   

2.
利用溶剂热法合成2种有机杂化硫代锑酸盐化合物[Co(en)3](Hen)SbS4(1)和[Ni(en)3]2Sb2S5(2)(en=乙二胺),它们的结构经IR、元素分析和单晶x-射线衍射表征。1是由孤立四面体[SbS4]3-阴离子、质子化有机胺[Hen]+和配阳离子[Co(en)3]2+组成,而2是由孤立二聚阴离子[Sb2S5]4-和配阳离子[Ni(en)3]2+组成.  相似文献   

3.
合成了二维异核配位聚合物{[Ag2Fe(SCN)6](C5H6N)(H2O)}∞(化学式:C11H8Ag2FeN7OS6),并对其结构进行了X射线表征.单晶衍射结果表明,该配合物属三斜晶系,空间群P1,晶包参数a=0 76285(4)nm,b=0 84576(4)nm,c=0 91531(3)nm,α=99 953(2)°,β=99 821(2)°,γ=95 479(2)°,V=0 56836(4)nm3,Z=1.八面体配位的Fe(Ⅲ)中心通过六个1,1,3 μ3 SCN-和周围的三个Ag2S2环连接成二维的阴离子网状骨架结构,质子化的吡啶以阳离子的形式和水分子一起存在于晶体结构中.  相似文献   

4.
以Dawson型多金属氧酸盐和异烟酸为原料,合成了一种新的超分子化合物(C6NO2H6)6[α-P2W18O62]·10H2O.通过元素分析、红外光谱、热重分析和X射线单晶衍射确定了该化合物的组成和结构.结构解析表明:该化合物是通过[α-P2W18O62]6-多氧阴离子和质子化的异烟酸阳离子之间的静电引力与广泛的氢键相互作用形成3D超分子结构.同时也进行了电化学及紫外光谱研究.  相似文献   

5.
合成了含有十钒酸阴离子的超分子化合物[ Na(DB18C6)(H20)2]3V10O28[CH3OH].[H3O]3并通过X射线衍射分析、IR光谱及元素分析对其结构进行了表征.单晶X射线衍射分析表明化合物属于单斜晶系,P21/m空间群,a=15.5520(16) nm,b=18.7581( 19)nm,c=16.3619(18) nm,β=109.0390(10),V=4512.1(8)nm3,Z=2,F(000)=2380,R1=0.0606,wR2=0.1312.化合物的晶体结构单元由一个无质子化的十钒酸根多阴离子、一个甲醇分子、3个[ Na( DB18C6)(H2O)2]+和3个H3O+阳离子组成,并且彼此之间通过静电力和氢键形成稳定的三维结构.  相似文献   

6.
以磺胺醋酰药物为阴离子,合成7种离子液体,以1H NMR和IR确证其结构;低温差示扫描量热(DSC)测定熔点或玻璃化转变温度,结果较相应钠盐有较大程度降低;离子液体对大肠杆菌和金黄色葡萄球菌的抑菌性比较发现,大肠杆菌敏感度强于金黄色葡萄球菌,并且此类离子液体抑菌性主要由季铵阳离子种类决定,吡啶离子液体的抑菌力强于甲基咪唑,长链离子液体优于短链离子液体.  相似文献   

7.
以Dawson型多金属氧酸盐和异烟酸为原料,合成了一种新的超分子化合物(C6NO2H6)6[α-P2W18O62].10H2O.通过元素分析、红外光谱、热重分析和X射线单晶衍射确定了该化合物的组成和结构.结构解析表明:该化合物是通过[α-P2W18O62]6-多氧阴离子和质子化的异烟酸阳离子之间的静电引力与广泛的氢键相互作用形成3D超分子结构.同时也进行了电化学及紫外光谱研究.  相似文献   

8.
用脂肪醇与环氯丙烷在碱性条件下合成了季铵盐型阳离子表面活性剂。所得产品用X-射线单晶衍射法测定了晶体结构。该化合物采用双分子层结构,整个化合物由交叉的线性烷基链、季胺阳离子和溴离子组成。用偏光显微镜、差示扫描量热(DSC)技术研究了其液晶行为,证明该化合物为近晶相热致液晶。  相似文献   

9.
通过碘化铋与丝氨酸锂盐间的室温固-固反应合成了纳米丝氨酸铋(Ⅲ)配合物:(C3H6O3N)2Bi( μ-I)2Bi[(C3H6O3N)I]·H2O.经元素分析、X-射线粉末衍射(XRD)、远红外光谱和差热-热重分析(TG-DTA)等进行表征,确定了配合物的组成和结构.同时对XRD衍射数据进行指标化,确定配合物的晶系和晶胞参数:丝氨酸铋配合物的晶体结构属于正交晶系,其晶胞参数为a=0.796 7 nm,b=1.9875 nm,c=2.2034 nm.  相似文献   

10.
通过碘化铋与丝氨酸锂盐间的室温固-固反应合成了纳米丝氨酸铋(Ⅲ)配合物:(C3H6O3N)2Bi(μ-I)2Bi[(C3H6O3N)I].H2O.经元素分析、X-射线粉末衍射(XRD)、远红外光谱和差热-热重分析(TG-DTA)等进行表征,确定了配合物的组成和结构.同时对XRD衍射数据进行指标化,确定配合物的晶系和晶胞参数:丝氨酸铋配合物的晶体结构属于正交晶系,其晶胞参数为a=0.796 7nm,b=1.987 5nm,c=2.203 4nm.  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.
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   

14.
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   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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.
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   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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