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141.
To develop photo-tunable chromatography, several azobenzene derivatives were immobilized or modified on silica gels or incorporated into polymers. The supports prepared were used as stationary phases in semi-micro HPLC, and the photo-dependence of their retention evaluated. On these stationary phases, the retention measured with 2-propanol in hexane was increased by UV irradiation; in contrast, the retention was decreased when methanol was used as mobile phase. It was assumed that the polarity of the stationary phase increases when the molecular structure of the azobenzene moieties changes from the trans to the cis form. On irradiation of the column with visible light after UV irradiation and with methanol as mobile phase, the change of retention proved to be reversible. However, this reverse change was less dramatic than the initial change. Such retention behavior is attributable to photo-isomerization of the azobenzene moieties. These findings will be exploited in our development of new photo-tunable stationary phases and new photo-controlled separation systems. 相似文献
142.
Mine Yurtsever Belkis Ustamehmetoglu A. Sezai Sarac A. Mannschreck 《International journal of quantum chemistry》1999,75(2):111-117
Fully optimized semiempirical quantum‐chemical calculations of photochromic spiropyrans are presented. The vertical ionization potentials are calculated and their variation with substitutions are correlated to experimental oxidation potentials. The effects of the substitutions are studied and the partial charges on indoline and pyran components generated by HOMO are found to be responsible for the variations. The deactivating groups on the indoline ring system and deactivating groups on the pyran system increase the ionization potential and, consecutively, the oxidation potential. ©1999 John Wiley & Sons, Inc. Int J Quant Chem 75: 111–117, 1999 相似文献
143.
利用光致变色材料的灰度分阶特性可以实现多阶光存储。以傅里叶光学和光致变色记录符的可叠加性为基础,采用霍普金斯标量衍射理论的经典归-化坐标,对光致变色多阶光存储中的光学串扰进行了理论建模和数值分析。作为后续电通道补偿设计的前提。数值计算结果表明:相邻记录符与盘基信号的交叉串扰项是光学串扰的主要成分,且随着中心距的增加,相邻记录符引起的串扰迅速降低;当无寻道误差时,邻道记录符引起的串扰可以忽略;高阶记录符引起串扰要明显高于低阶的串扰。且影响多阶存储的可分阶性;实验结果很好地验证了所建立的模型的合理性。 相似文献
144.
145.
早在1978年,光致变色研究的先驱者Heller教授就提出光致变色反应可用于光信息存储和光记录材料,十年之后诺贝尔化学奖获得者Lehn教授又提出了光子器件,光致变色分子和体系的设计与合成为研制不同种类的光子器件提供了物质基础和可能性[1].具有光致变色特性的有序分子膜的制备及光学物理性质研究更吸引着众多的科学家进入这一研究领域[2~4]. 相似文献
146.
Investigation on photochromism of 1,2-bis(1,4-dimethyl-2-phenyl)perfluorocyclopentene 总被引:1,自引:1,他引:0
LIU Xuedong TONG Qingxiao SHI Ming & ZHANG Fushi Key Lab of Organic Optoelectronics & Molecular Engineering of Ministry of Education Department of Chemistry Tsinghua University Beijing China 《中国科学B辑(英文版)》2006,49(6):517-521
The photochromic diarylethene, 1,2-bis(1,4-dimethyl-2-phenyl)perfluorocyclopentene has been synthesized and its single crystal can be obtained in hexane at -4℃. The structure of diphenylperluorocyclopentene bearing C2/c space group and monoclinic crystal system is very different from that of dithienylperfluorocyclopentene derivatives bearing Pī space group and triclinic crystal system by X-ray crystallographic analysis. The compound undergoes the phototchromic reaction in solution but no optical activity in single crystal. In addition, its optimum conformation in solvent is also discussed. 相似文献
147.
Carboxylated Photoswitchable Diarylethenes for Biolabeling and Super‐Resolution RESOLFT Microscopy 下载免费PDF全文
Dr. Benoît Roubinet Dr. Mariano L. Bossi Dipl.‐Biophys. Philipp Alt Dr. Marcel Leutenegger Dr. Heydar Shojaei M. Sc. Sebastian Schnorrenberg Dr. Shamil Nizamov Prof. Dr. Masahiro Irie Dr. Vladimir N. Belov Prof. Dr. Stefan W. Hell 《Angewandte Chemie (International ed. in English)》2016,55(49):15429-15433
Reversibly photoswitchable 1,2‐bis(2‐ethyl‐6‐phenyl‐1‐benzothiophene‐1,1‐dioxide‐3‐yl)perfluorocyclopentenes (EBT) having fluorescent “closed” forms were decorated with four or eight carboxylic groups and attached to antibodies. Low aggregation, efficient photoswitching in aqueous buffers, specific staining of cellular structures, and good photophysical properties were demonstrated. Alternating light pulses of UV and blue light induce numerous reversible photochemical transformations between two stables states with distinct structures. Using relatively low light intensities, EBTs were applied in biology‐related super‐resolution microscopy based on the reversible saturable (switchable) optical linear fluorescence transitions (RESOLFT) and demonstrated optical resolution of 75 nm. 相似文献
148.
WANG YaZhuo WU Jia MA DeWang & DING Ji ong Key Laboratory of Molecular Engineering of Polymers of Ministry of Education 《中国科学B辑(英文版)》2011,(2)
Bacteriorhodopsin (BR) is a photochromic membrane protein isolated from a strain of halobacteria.Embedment of BR into a polymeric matrix enables the application of the photoactive protein as an optical material.In this work,a chemically crosslinked BR/gelatin film was prepared.The cross-linked film was found to be highly stable even under extreme alkaline or detergent circumstance while BR maintained its bioactivity.The treatments of base and detergents also led to dramatic prolongation of the lifetime of M... 相似文献
149.
具有可逆颜色变化和适当变色寿命的光致变色材料对于无墨水和可擦除打印技术十分重要。我们将1,4,5,8-萘四羧酸二酐与甲硫氨酸结合,设计了一种基于 1,4,5,8-萘二酰胺(NDI)的桥联有机配体(H2ncm),并以 Zn2+和 H2ncm为原料,通过溶剂热反应合成了2种配位聚合物。化合物[Zn(ncm)(H2O)4]·2DMF (1)包含1个Zn2+、1个ncm2-配体、4个配位水分子和2个DMF分子。Zn2+处于八面体的配位环境中,并通过 ncm2-配体连接形成链状结构。化合物[Zn2(ncm)2(H2O)4] (2)包含 2个 Zn2+、2个 ncm2-配体和4个配位水分子。2个Zn2+原子通过2个羧基桥联形成双核结构,并进一步通过ncm2-配体连接形成二维层结构。2显示出从黄色到深棕色的光致变色现象。这种光诱导产生的颜色可以稳定至少3周,但在70 ℃加热时在5 min内即可恢复本来的颜色。我们证明了这种光致变色是源于光照射下NDI·自由基的产生。 相似文献
150.