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根据偶氮苯顺反异构定量公式ln[(A_0-A_(eq))/(A_t-A_(eq))]=k_tt和ln[(A_(eq)-A_0)/(A_(eq)-A_t)]=k_c(k_H)t,利用UVVis光谱研究系列D-π-A型偶氮苯衍生物在溶液中反-顺光异构反应速率常数、光回复异构反应速率常数、热回复异构反应速率常数和异构转化率。结果表明,系列偶氮苯衍生物光异构和热回复异构反应的速率常数数量级范围分别为10~(-3)~10~(-2)s~(-1)、10~(-5)~10~(-1)s~(-1),除化合物3',5'-二溴-3-甲基-4-羟基偶氮苯和3',5'-二溴-3,5-二甲氧基-4-羟基偶氮苯外,其他化合物的异构转化率很高,有作为光控开关材料的应用前景。 相似文献
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[目的]为将光药理学方法应用于农药学研究。[方法]在阿维菌素B1a分子的C5-OH引入光致异构基团偶氮苯。[结果]合成了3个偶氮苯-阿维菌素衍生物,测试了光物理化学性质和生物活性。这些衍生物光致异构反应的转化率为42%~47%,具有良好的抗疲劳性和热稳定性。化合物3a对蚊幼虫和黏虫、3c对蚊幼虫的活性较好,但光照前后活性差异较小。[结论]偶氮苯-阿维菌素衍生物的顺反异构变化可以被光可逆控制,具有成为新型光控活性分子的潜能。 相似文献
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以对硝基苯胺、亚硝酸钠、2,5-二甲基苯酚和正溴丁烷为原料,采用重氮-偶合反应方法,合成了一种含偶氮基团的非线性生色团有机分子:1-正-丁氧基-2,5-二甲基-4-(4'-硝基苯基偶氮)苯.分别用FTIR、UV-vis和XRD对其化学结构和性能进行了分析和表征.红外光谱图中2 930、2 860 cm-1处出现的-C4H9特征吸收峰和紫外光谱中400 nm左右出现的峰是-N=N-特征吸收峰,表明1-正-丁氧基-2,5-二甲基-4-(4'-硝基苯基偶氮)苯已成功合成.X射线衍射测试结果表明1-正-丁氧基-2,5-二甲基-4-(4'-硝基苯基偶氮)苯为液晶分子.该生色团分子的成功合成为研究高性能聚合物光折变材料体系提供了良好助剂. 相似文献
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1-正-丁氧基-2,5-二甲基-4-(4′-硝基苯基偶氮)苯的合成及表征 总被引:1,自引:1,他引:0
以对硝基苯胺、亚硝酸钠、2,5-二甲基苯酚和正溴丁烷为原料,采用重氮-偶合反应方法,合成了一种含偶氮基团的非线性生色团有机分子:1-正-丁氧基-2,5-二甲基-4-(4′-硝基苯基偶氮)苯。分别用FTIR、UV-vis和XRD对其化学结构和性能进行了分析和表征。红外光谱图中2 930、2 860 cm-1处出现的—C4H9特征吸收峰和紫外光谱中400 nm左右出现的峰是—N N—特征吸收峰,表明1-正-丁氧基-2,5-二甲基-4-(4′-硝基苯基偶氮)苯已成功合成。X射线衍射测试结果表明1-正-丁氧基-2,5-二甲基-4-(4′-硝基苯基偶氮)苯为液晶分子。该生色团分子的成功合成为研究高性能聚合物光折变材料体系提供了良好助剂。 相似文献
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间(对)甲酰基偶氮氯膦的合成及其与稀土元素显色反应的研究 总被引:4,自引:0,他引:4
变色酸双偶氮衍生物是一类重要的显色剂,常用于稀土、碱土和铀钍的测定。自偶氮胂M和偶氮硝羧合成以后,不对称变色酸双偶氮衍生物的研究与应用发展很快。1974年,我们合成了甲酰基、乙酰基、丙酰基偶氮羧等不对称变色酸双偶氮衍生物。实验证明,甲酰基、乙酰基和丙酰基是有效的功能团。本文介绍将甲酰基引进偶氮氯膦类试剂以后所得到的间(对)甲酰基偶氮氯膦Ⅰ对甲酰基偶氮氯膦 2-(4-氯-2-膦酸基苯偶氮)-7-(4-甲酰基苯偶氮)-1,8-二羟基萘-3,6-二磺酸Ⅱ间甲酰基偶氮氯膦 2-(4-氯-2-膦酸基苯偶氮)-7-(3-甲酰基苯偶氮)-1,8-二羟基-3,6-二磺酸 相似文献
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2,3,5,6-四氯-4-甲基苯腈是一种新型的杀菌剂,可用于合成液晶材料、药物、染料和其他工业制品,有巨大的市场发展前景。2,3,5,6-四氯-4-甲基苯腈是带有吸电子基的甲苯衍生物,可以由对甲基苯腈经过氯化而合成。经过反复实践研究出了一条反应条件温和,易于实现工业化生产的工艺路线。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
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醋酸纤维素取代基分布与性质的关系 总被引:9,自引:0,他引:9
分析了以吡啶为溶剂的醋酸纤维素的13C-NMR核磁共振谱,得出了三种不同位置羟基的取代度。结合X—射线和DSC分析,初步说明具有相同取代度但未经水解和经过水解的醋酸纤维素(CA) 性质上的差异是由于三个羟基上的取代度分布不同及消晶程度差异所致。 相似文献
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1 INTRODUCTIONBecause of importance of equations of state (EOS)in science and industry,hundreds forms of EOS havebeen presented since latter 19th century.It seems impossible to develop a general equation covering vari-ous kinds of EOS.But for cubic EOS,several generalequations have been reported already. Martin presented the first general equation whichis following p=RT/V-α(T)/(υ β)(υ γ) δ(T)/υ(υ β)(υ γ) (1) Kumar et a1.presented an equation called the most general form of a density-cubic or, alterna tively,volume-cubic mathematical equation,the form of which is as follows 相似文献