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1.
以对苯二甲醛和4,4’-二氨基偶氮苯衍生物为原料合成得到了3种含偶氮基聚席夫碱化合物,并利用红外光谱、紫外-可见吸收光谱及荧光光谱进行了表征.结果表明,取代基为-OH时聚合物最大紫外吸收波长λmax最大,荧光光谱显示3种聚合物荧光性都比较弱.采用不含偶氮基的类似结构的聚席夫碱化合物作对照,表明偶氮基团的引入减弱了聚合物的荧光性.  相似文献   

2.
以2-羟基-1-萘醛和4-氨基安替比林为原料,在一定条件下反应,得到一种席夫碱化合物,利用红外光谱、核磁共振氢谱等对其结构进行确认,并用红外光谱和差示扫描量热分析对其热致变色性能进行研究.结果表明此席夫碱的可逆热色性是由于烯醇式和顺式酮两种构型的互变导致的.  相似文献   

3.
5-(4''-磺胺苯基偶氮)水杨醛席夫碱的合成及其热色性研究   总被引:5,自引:0,他引:5  
以乙酰苯胺,水杨醛,胺类为原料,经氯磺化,氨解,重氮化,偶联和缩合反应,合成了9种新的偶氮磺胺类席夫碱化合物,利用红外光谱,核磁共振氢谱和元素分析等对其结构进行了确认,并对其热致变色性能作了实步研究。  相似文献   

4.
从盐酸氨基脲出发,经与水杨醛缩合,再与氯化铜配合等步骤,生成了席夫碱的配合物.目标化合物经IR、远红外光谱以及元素分析确证了分子结构,并通过差示量热扫描分析(DSC)测定了其变色的温度范围.升温时,在50~110 ℃有变色峰出现;降温时,在45~85 ℃出现变色峰.与目测法结果相符,证明该化合物是一新型可逆热致变色配合物.  相似文献   

5.
从盐酸氨基脲出发,经与水杨醛缩合,再与氯化铜配合等步骤,生成了席夫碱的配合物。目标化合物经IR、远红外光谱以及元素分析确证了分子结构,并通过差示量热扫描分析(DSC)测定了其变色的温度范围。升温时,在50~110℃有变色峰出现;降温时,在45~85℃出现变色峰。与目测法结果相符,证明该化合物是一新型可逆热致变色配合物。  相似文献   

6.
合成了两种新型噻唑类双席夫碱,5-噻唑醛缩乙二胺双席夫碱(A)和5-噻唑醛缩1,2-环己二胺双席夫碱(B),通过紫外-可见光谱、红外光谱、1 H-NMR共振谱、元素分析对其进行了结构表征.培养得到了5-噻唑醛缩1,2-环己二胺晶体,经X-射线衍射测定,该化合物属单斜晶系,空间群为P2(1)/n,晶胞参数a=11.091(6),b=17.821(10),5.492(9),β=92.97(6)°,V=305 8(3)3,Z=8.  相似文献   

7.
一个含有端基双键的席夫碱型液晶化合物的合成与表征   总被引:6,自引:0,他引:6  
合成了一个带有端烯基席夫碱液晶化合物,通过元素分析,红外光谱,紫外光谱等进行了表征。该化合物的液晶性通过带热台的偏光显微镜进行了表征,初步证明其织态结构为破扇状形态、属于近晶型结构。  相似文献   

8.
设计合成了1个低代枝状多偶氮化合物,并对其可逆光致异构性质进行了研究。目标化合物在紫外/目光的驱动下能进行顺反构型的可逆转变,预防其能实现分子水平上的“开”和“关”过程。  相似文献   

9.
新型偶氮卟啉荧光化合物的合成、表征及光谱性质   总被引:1,自引:0,他引:1  
以对氨基苹甲醛和苯酚(或蔡酚)为原料通过重氮化和偶合反应合成偶氟醛,偶氮醛与吡咯反应得到2种新型偶氮卟啉——四对(4-羟基偶氮苯基)苯基卟啉(3)和四对(2-羟基偶氮萘基)苯基卟啉(4).通过核磁氢谱、红外和质谱对其结构进行了表征,研究了紫外和荧光光谱性质,并与无取代的四苯基卟啉的光谱性质进行了比较.新化合物紫外吸收有红移现象,且能在红光区发射荧光.化合物4的荧光光谱有较大红移,且在851nm处发现荧光发射峰.  相似文献   

10.
一种水溶性偶氮聚电解质的合成及光响应性   总被引:7,自引:0,他引:7  
为合成水溶性含偶氮基团的聚电解质 ,利用重氮化偶合反应 ,将羧基引入偶氮化合物中 ,合成了一种新型的水溶性偶氮化合物。用 1 H- NMR,IR和 UV- Vis证实了其结构。该化合物聚合后得到的聚电解质水溶液随着 p H值的变化 ,在紫外可见光谱图上的吸收强度和峰位置都发生显著地变化 ,表现出 p H值敏感性。该聚电解质同时具有良好的光响应性和自组装性。拓宽了含偶氮基团聚合物的应用范围  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.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  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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