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1.
应用相转移催化法合成了11个新的N,N-1,4-羰基苯氧乙酰基-N′,N′-二芳氧基乙酰基二肼.  相似文献   

2.
由二苯并-18冠-6与二元酸反应制得的冠醚酮酸1用黄鸣龙法还原成冠醚烷酸2,2经酰氯化生成4′,4″(5″)-双(氯甲酰基亚烷基)二苯并-18-冠-6(3),再将3与4′,5′-二氨基二苯并-18-冠-6缩合,制得新的筒状大五三环穴醚4a和4b。  相似文献   

3.
相转移催化法合成1,4-苯二氧基二乙酸及其衍生物   总被引:1,自引:0,他引:1  
合成了1,4-苯二氧基二乙酸及其衍生物─—1,4-苯二氧基二乙酸、1,4-苯二氧基二乙酰氯、1,4-苯二氧基二乙酸二苯酚酯、1,4-苯二氧基二乙酰二苯胺、N,N-1,4-苯二氧基二乙酰基-N',N'-二苯氧基乙酰基二肼,合成反应采用了相转移催化技术,提高了产率,预计合成的化合物是一类新型的具有双活性中心的植物生长调节剂.  相似文献   

4.
报道了一种未见报道的、新的双核配体N,N,N′,N′-四(1′-苯并三氮唑乙基)-2,7-二甲胺基-8-羟基喹啉含铜二氧合物的合成和表征,配合物的光谱和气相色谱测试结果表明这类三元络的中,二氧是以过氧桥基离子桥连两CU(Ⅱ)核,氧合物中量的比为Cu(Ⅰ):O2=1:1。  相似文献   

5.
盘花垂头菊倍半萜和酚类化合物结构的研究   总被引:4,自引:2,他引:4  
从盘花垂头菊全草分离出10个化合物,经IR,^1HNMR,^13CNMR,DEPT,FABMS,EIMS等光谱方法分别鉴定为:1β,8-二当归酰氧基-2β-乙酰氧基-3β-羟基-4α-氯-10,11-环氧-没药-7(14)-烯(1);化合物1的异构体(2),对羟基甲酸,2-(2′-正十九酰基)-苯乙基酯(3a);对羟基苯甲酸,2-(2′-正二十一酰基)-苯乙基酯(3b);对羟基苯甲醛(4);对羟基苯乙酮(5);苯甲酸(6);4-羟基-3,5-二甲氧基苯甲醛(又称丁香醛)(7);7-甲氧基-6-羟基香豆素(又称异东莨菪素)(8);乌苏酸(9),其中1,2,3a和3b是新化合物,其它化合物(4-9)是首次从该属植物中分到的。  相似文献   

6.
新型偶氮苯的质谱特征与非线性光学性质   总被引:11,自引:1,他引:11  
合成了偶氮苯染料-4-硝基4′-二(N,N′-羟乙基)氨基偶氮苯及其3个衍生物.染料分子的质谱行为与分子内电荷转移态有关,存在优势的M+1碎片峰.染料分子的二阶非线性光学系数与其偶极矩的复合量用溶剂化变色法测得为≥290×10-30D·esu-1  相似文献   

7.
以氢氧化钠为缩合剂,2,2’-二(邻-羟基苯氧基)丙烷分别与N-对甲苯基二乙醇胺二对甲苯磺酸酯,N-对甲苯磺酸基二乙醇胺二对甲苯磺酸酯反应生成二苯型」16「环系氮杂冠醚化合物.2。在过量苯酚存在下,用40%氢溴酸去对甲苯磺酸基得到相应的亚胺型氮杂冠醚.2,2‘-二(邻-羟基苯氧基)乙醚分别与及N-苯基二乙醇胺二对甲苯碘酸酯缩合得到二苯型「18」环系氮杂冠醚化合物。  相似文献   

8.
基于紫外光谱、红外光谱、荧光光谱和计算机模拟技术研究了β-环糊精对4,4′-二羟基二苯乙烷的包结行为.结果表明,4,4′-二羟基二苯乙烷经包结后其紫外吸收有所增加,吸收峰红移了2~3 nm;红外特征峰被β-环糊精不同程度掩盖且特征吸收峰不同程度地发生一定的偏移;荧光强度随β-环糊精浓度的增大而逐渐增强;β-环糊精与4,4′-二羟基二苯乙烷形成稳定的1∶1包结物,包结常数为7.82×103L.mol-1;PM3优化后包结物的构型为4,4′-二羟基二苯乙烷分子部分进入β-环糊精空腔,模拟包结物的稳定化能为-59.13 kJ.mol-1.  相似文献   

9.
通过酰氯与胺的作用合成了配体N,N,N′,N′-四〔2-(2-吡啶基)乙基〕(o,m,p)苯二甲酰胺。该配体和铜(Ⅱ)配合,合成了三种新配合物,并以红外光谱、电子光谱、摩尔电导率、元素分析及核磁共振谱进行了表征。  相似文献   

10.
利用Higashi芳香聚酯直接缩聚法的原理,采用分步投料溶液共聚合的方法,以N,N′-己二撑-1,6-双苯偏三酸酰亚胺二酸(IA6)、对羟基苯甲酸(p-HBA)和4,4′-二羟基二苯酮(DHBP)为单体原料,合成了一类聚酯酰亚胺三元共聚物。采用核磁共振(NMR)分析了共聚物的化学结构及组成,并用差热分析(DSC)、偏光显微镜(PLM)、广角X射线衍射(WAXD)对聚合物在熔融过程中的相转变及其液晶特性进行了研究。结果表明,由合适的单体组成比合成的共聚物在升温过程中呈现明显的向列型热致液晶特性,在降温过程中则未观察到液晶的相转变。各种分析手段的结果表明,DSC和WAXD的测试结果与在偏光显微镜下观察到的共聚物在熔融过程中所呈现的相转变行为相吻合。  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.
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.
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   

18.
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   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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