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1.
以间苯二甲酸为原料,经酯化、氨解、关环和取代四步反应合成了1,3-二(2-甲氧酰甲硫基-1,3,4-噻二唑)-苯,进一步与乙二醇、1,3-丙二醇和1,6-己二醇通过酯交换反应合成了含有1,3,4-噻二唑与苯共轭结构的聚酯(P1~P3).采用IR、1 H NMR及MS对中间体和聚酯的结构进行表征.利用GPC测得聚酯P1~P3的Mw分别为11 352、15 350、14 957g/mol,PDI分别为1.96、2.24、2.18.聚酯能溶解于DMF、DMSO、DMAC和NMP等溶剂.TG-DTA测得P1~P3的5%失重温度分别为257.89、260.88、267.01℃.化合物4和聚酯P1~P3均在361~368nm范围内发射紫光.测试结果表明,所合成聚酯具有良好的溶解性、热稳定性及荧光性能.  相似文献   

2.
以间苯二甲酸为原料,经多步反应合成了两种新型烷氧基偶氮苯-喹啉化合物5-[8-(丁氧基)喹啉-5-偶氮]-1,3-苯二甲酸二乙酯(5a)和5-[8-(辛氧基)喹啉-5-偶氮]-1,3-苯二甲酸二乙酯(5b),通过IR、UV-Vis、1 H NMR和MS等对其结构和性能进行了表征.利用吸收光谱和发射光谱研究了目标化合物的反-顺异构化和发光性能.目标化合物5a和5b(2.0×10-5 mol/L的DMF溶液),在365nm紫外光照射下,400nm处的偶氮苯-喹啉结构K带π-π*跃迁吸收峰及267nm处芳香环的B带π-π*跃迁吸收峰逐渐减弱,光照6min后达到光稳态.目标化合物5a和5b(2.0×10-5 mol/L的DMF溶液)均以311nm光激发,分别在420,418nm处发射蓝紫色荧光.  相似文献   

3.
以间苯二甲酸为原料,经过多步合成了1种含偶氮苯和1,3,4-噁二唑基团化合物5-[4-(十六烷氧基)苯基偶氮-]1,3-苯基-二-(1,3,4-噁二唑硫基)乙酸甲酯(8),利用IR、UV-vis、1 H NMR对其结构进行表征.该化合物四氢呋喃溶液紫外光谱中,偶氮苯结构K带的最大吸收波长为360nm,摩尔吸光系数ε为27 476L.mol-1.cm-1.在365nm紫外光照射下,偶氮苯基团发生反-顺异构化,照射5min后达到光稳态,光稳态时偶氮苯基团光致反顺异构化速率常数kp为1.338 9min-1,反式异构体转化效率R为80.95%,顺式异构体比例Y为84.99%,光稳态时偶氮苯K带最大吸收波长由360nm蓝移至326nm,将其置于暗室中,35h后恢复到光照前状态.  相似文献   

4.
以间苯二甲酸为原料,经多步反应合成了1种新型烷氧基偶氮苯-喹啉化合物(E)5-[8-(十六烷氧基)喹啉-5-偶氮]-1,3-苯二甲酸二乙酯,通过IR、UV-Vis和1 H NMR对其结构进行了表征.利用吸收光谱和发射光谱研究了目标化合物的反-顺异构化和发光性能.目标化合物(2.0×10^-5 mol/L的DMF溶液)在365nm紫外光照射下,398nm处的偶氮苯-喹啉结构K带π-π*跃迁吸收峰及267nm处芳香环的B带π-π*跃迁吸收峰逐渐减弱,光照7min后达到光稳态.目标化合物(2.0×10^-5 mol/L的DMF溶液)以312nm光激发下,在418nm处发射蓝紫色荧光.  相似文献   

5.
利用1,3-二(2',4'-二羧酸苯基)苯、2,2'-联吡啶和氧化镉在水热条件下反应制备了一种新型超分子化合物{Cd(H2dtca)(bipy)}[H2dtca=1,3-二(2',4'-二羧酸苯基)苯,bipy=2,2'-联吡啶].通过X-射线单晶衍射测定了化合物的晶体结构,并利用元素分析、红外光谱等技术对其进行表征.结构研究发现该晶体属于单斜晶系P21/n空间群,a=1.604 06(7)nm,b=1.037 30(4)nm,c=1.720 97(7)nm;β=101.803 0(10)°;Z=4,wR1=0.034 2,wR2=0.079 5.晶体结构分析表明2个镉在1个1,3-二(2',4'-二羧酸苯基)苯的连接下形成了一个双核结构,再在氢键作用下,形成3维超分子结构.此外,还研究了配合物的固态荧光性质.  相似文献   

6.
合成了一个新的配合物{[Cd(mip)(1,3-Bip)·H2O]}n(H2mip=5-甲基间苯二甲酸;1,3-Bip=1,3二(咪唑)-丙烷),并测定了其晶体结构,X衍射结构分析表明:该化合物的化学式为C18H18CdN4O5,该晶体属单斜晶系,P2(1)/n空间群,晶胞参数:a=1.028 1(3)nm,b=1.142 2(4)nm,c=1.728 2(6)nm,α=90°,β=104.390(4)°,γ=90°,V=1.965 9(11)nm3,Z=4,Dc=1.631g/cm3,最终偏差因子R1=0.050 1,wR2=0.104 7(Iσ(I)),F(000)=968,中心金属Cd(II)离子与来自3个5-甲基间苯二甲酸根的4个氧原子以及两个1,3二-(咪唑)-丙烷的两个氮原子配位,形成六配位的变形八面体构型.  相似文献   

7.
5,6-二(2-甲氧基苯胺基)-2,3-吡啶二酮的合成和晶体结构   总被引:1,自引:1,他引:0  
在无溶剂条件下,由3-羟基-2(1H)-吡啶酮与2-甲氧基苯胺在NaIO3作用下合成了5,6-二(2-甲氧基苯胺基)-2,3-吡啶二酮,其结构经1HNMR表征.采用X-射线单晶衍射仪测定了产物的晶体结构,晶体结构属单斜晶系,空间群P21/n,晶胞参数为:a=1.1655(2)nm,b=0.72080(10)nm,c=2.0326(4)nm,α=90°,β=92.17(3)°,γ=90°,V=1.7063(5)nm3,Z=4,F(000)=736,Mr=351.36,Dc=1.368g/cm3,μ=0.098mm-1,R1=0.0587,wR2=0.1365.  相似文献   

8.
以间苯二甲酸为原料,经多步反应合成了1种新型烷氧基偶氮苯化合物5-[4-(十六烷氧基)苯基偶氮]-1,3-笨二甲酸二乙醋.用FT-IR,UV-vis、1 H NMR对其结构进行了表征.该化合物(3.24×10-5 mol·L-1四氢呋喃溶液)紫外光谱K带的最大吸收波长为353 nm,摩尔吸光系数ε为23 950 L·mol-1·cm-1.在365 nm紫外光照射下,该化合物发生反-顺异构化,光照8 min后达到光稳态,K带最大吸收波长蓝移至311 nm,将其置于暗室中,40 h后恢复到光照前状态.光稳态时偶氮发色团反-顺异构化转化效率R为86.19%,顺式异构体的比例Y为90.5%.  相似文献   

9.
在稀盐酸的存在下,以亚硝酸正丁酯为重氮化试剂,合成出4,4’-二偶氮苯重氮氨基苯、1,3-二-(4-硝基苯)-三氮烯、安替比林重氮氨基苯及1-(4-安替比林)-3-(4-硝基苯)-三氮烯.该重氮化反应效果好,合成产品的纯度高,产率也较高.  相似文献   

10.
以苯胺为原料通过偶联反应合成了4,4′-二乙炔基偶氮苯,并通过1H NMR对各步合成产物结构进行了分析.1H NMR结果表明:4,4′-二乙炔基偶氮苯合成产率达到85%.产物的紫外光谱显示:在波长243 nm处出现苯环π-π*吸收;350 nm处显示了偶氮苯发色团的反式特征吸收峰;420 nm左右出现偶氮苯顺式特征吸收峰.不同照射时间下的紫外光谱图表明,4,4-二乙炔基偶氮苯氯仿溶液在365 nm紫外光照射下会发生顺-反异构现象.  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.
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   

19.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

20.
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   

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