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1.
合成制备了2,6-二甲基-N-庚烷基吗啉及其盐酸盐客体分子,利用1H NMR考察了对称四甲基六元瓜环、七元瓜环以及八元瓜环与2,6-二甲基-N-庚烷基吗啉及盐酸盐的相互作用,结果表明上述瓜环均能与2,6-二甲基-N-庚烷基吗啉及其盐酸盐发生相互作用,并选择性包结烷基部分,形成主客体包结配合物。  相似文献   

2.
部分甲基取代瓜环合成技术的改进与分离的研究   总被引:1,自引:0,他引:1  
瓜环(cucurbit[n]uril)是继冠醚(crown ether)、环糊精(cyclodetrin)和杯芳烃(calixarene)之后备受瞩目的一类新型笼状大环主体分子化合物,它在主客体化学、自组装超分子化学等领域展现良好的应用前景.然而,瓜环的溶解度小、分离纯化难限制了它的进一步研究与应用.本文研究了以苷脲二聚体和甲基苷脲二醚合成部分甲基取代瓜环(n=5,6,7)的技术(即合成二甲基取代五元(DiMe-Q[5])、对四甲基取代六元瓜环(TMe-Q[6])、二甲基取代七元瓜环(DiMe-Q[7])的混合物);并研究了色谱分离部分甲基取代瓜环的方法,经1HNMR表征证明,用色谱分离的方法可分离得到纯度较高的DiMe-Q[5]、TMe-Q[6])和DiMe-Q[7]).  相似文献   

3.
本文用X射线单晶衍射方法研究六元瓜环与2-氨基甲基吡啶的相互作用及其结构特征。从主客体包结配合物的晶体结构,可以看出2-氨基甲基吡啶的吡啶环进入了瓜环空腔,形成1∶1包结配合物,表明2-氨基甲基吡啶与对六元瓜环有明显地相互作用。  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.
利用1H NMR技术和紫外-可见吸收光谱法考察了七元瓜环(Q[7])及对称四甲基六元瓜环(TMeQ[6])与甲基黄的分子包结作用,以及体系pH值对主客体作用的影响.结果表明,在体系pH约为1的条件下, Q[7]、TMeQ[6]与甲基黄均有明显的主客体相互作用,形成了1∶1的包结配合物,包结常数KQ[7]-g为3.54×106 L·mol-1,KTMeQ[6]-g为2.50×106 L·mol-1.测试了上述客体与不同瓜环作用体系的线性范围和检出限.  相似文献   

6.
以氯化镍与2-氨基甲基吡啶反应合成了配合物二氯化二(2-氨基甲基吡啶)(二水)合镍([Ni(2-ampy)2·(H2O)2]·Cl2).利用IR光谱、X-射线单晶衍射技术对其结构进行表征.通过荧光光谱研究了配合物与六、七、八元瓜环的相互作用.结果表明六、七、八元瓜环与配合物形成包结比为1:1的配合物.稳定常数为103数量级.  相似文献   

7.
用X射线单晶衍射方法研究六元瓜环和八元瓜环与苯胺盐酸盐的相互作用及其结构特征。从主客体包结配合物的晶体结构,可以看出苯胺的苯环进入了六元瓜环空腔,形成1:1包结配合物,两分子苯胺以相反的方向平行地进入八元瓜环空腔,形成了2:1包结配合物;表明苯胺与两种瓜环有不同的作用模式。  相似文献   

8.
利用1H NMR、质谱和紫外吸收光谱法考察了主体对称四甲基六元瓜环(TMeQ[6])与客体4-二甲胺基吡啶(DP)、N-丁基-4-二甲胺基吡啶碘化物(C4DP+)的自组装模式。结果表明,TMeQ[6]包结DP的吡啶环部分,而与C4DP+自组装时,则优先包结烷基链部分形成1∶1的类轮烷结构。  相似文献   

9.
利用^1H NMR技术、等温滴定量热(ITC)法和紫外吸收光谱等手段,研究了瓜环与二甲基苯甲酰亚甲基溴锍盐的相互作用.结果表明:Q[7]与二甲基苯甲酰亚甲基溴锍盐相互作用时,将其苯环包进Q[7]内腔内,形成1∶1的包结物.而Q[8]将两个二甲基苯甲酰亚甲基溴锍盐的两个苯环包进其内腔内形成1∶2的包结物.进一步通过热分析发现,包结物形成后,能够增强瓜环和二甲基苯甲酰亚甲基溴锍盐的热稳定性.  相似文献   

10.
利用^1H NMR技术,考察了新近合成的改性瓜环——对称四甲基六元瓜环(TmeQ[6])与5,5’-二甲基-2,2’-联毗啶(55’)、N-卞基-3-羟基吡啶(f9)、2-苯基-咪唑[4,5-f],10-邻菲咯啉(SCI)以及N,N’-二卞基-4,4’联吡啶(fx)等一系列有机化合物为客体的相互作用,解析、推测和归纳了这些作用产物的结构特征。  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 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   

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 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.
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   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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