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1.
采用微波技术,分别以N-烷基-2,3,3-三甲基-4,5-苯并吲哚六氟合磷酸盐与二甲氨基苯甲醛或3-吲哚甲醛为原料,在哌啶的催化下快速合成了4种苯并吲哚半菁染料H1~H4和4种苯并吲哚二次甲基菁染料F1~F4,并采用UV-Vis,1H NMR,IR,元素分析确证了产物的结构.研究了染料在不同溶剂中的吸收光谱性质,结果显示:两类染料在质子性溶剂中随着溶剂极性的增加最大吸收波长出现蓝移;而在非质子性溶剂中随着溶剂极性的减小最大吸收波长发生红移.同时,研究了染料H3和F2在生理条件下与鲑鱼精DNA、牛血清白蛋白、溶菌酶、淀粉酶和糜蛋白酶的相互作用,发现染料H3的荧光强度随着DNA浓度的增加而增强.  相似文献   

2.
新型水溶性荧光标示剂吲哚方酸菁染料的合成及光谱性能   总被引:1,自引:0,他引:1  
用方酸与不同的N烷基取代吲哚啉季铵盐缩合制备了一系列对称的水溶性方酸菁染料. 通过核磁共振氢谱和质谱对合成的染料结构进行了表征, 研究了它们在不同溶剂中的吸收和发射光谱. 结果表明, 随着溶剂极性的增大, 染料的吸收光谱发生蓝移, 表现为负向溶剂化效应, 在极性溶剂中的荧光量子产率比在水中的大. 考察了N位取代基对染料水溶液光稳定性的影响, 结果表明在吲哚环N原子上引入较大的苄基有助于提高光稳定性, 且随着苄基上取代基吸电子能力的增强, 染料的光稳定性增强.  相似文献   

3.
基于卤族元素对荧光素荧光性能的影响作用,采用甲磺酸为催化剂,分别以4-卤代(氟、氯、溴)间苯二酚为原料通过Friedel-Crafts酰化/环化脱水反应合成了2',7'-二卤代荧光素(DFF、DCF、DBF)。分析了不同卤族元素取代对荧光素的紫外-可见吸收和荧光发射光谱的影响,结果表明,与荧光素光谱相比,氟原子和氯原子取代对增强荧光发射强度效果明显,溴原子的引入降低荧光发射强度。考察了荧光染料浓度对其荧光强度的影响,结果发现,三种卤代荧光染料的浓度在1×10-5mol/L时均具有最大荧光发射强度。研究了染料的溶剂效应,发现荧光光谱随溶剂类型而变化,在极性溶剂中染料的荧光强度高、荧光发射波长较长,此外,在极性质子溶剂中斯托克斯位移比极性非质子溶剂中的大。  相似文献   

4.
基于卤族元素对荧光素荧光性能的影响作用,采用甲磺酸为催化剂,分别以4-卤代(氟、氯、溴)间苯二酚为原料通过Friedel-Crafts酰化/环化脱水反应合成了2',7'-二卤代荧光素(DFF、DCF、DBF)。分析了不同卤族元素取代对荧光素的紫外-可见吸收和荧光发射光谱的影响,结果表明,与荧光素光谱相比,氟原子和氯原子取代对增强荧光发射强度效果明显,溴原子的引入降低荧光发射强度。考察了荧光染料浓度对其荧光强度的影响,结果发现,三种卤代荧光染料的浓度在1×10-5mol/L时均具有最大荧光发射强度。研究了染料的溶剂效应,发现荧光光谱随溶剂类型而变化,在极性溶剂中染料的荧光强度高、荧光发射波长较长,此外,在极性质子溶剂中斯托克斯位移比极性非质子溶剂中的大。  相似文献   

5.
对4-氧-2,2,6,6-四甲基哌啶-1-氧自由基在26种不同溶剂中的顺磁共振谱进行了测定,发现超精细分裂常数AN随溶剂极性的增加而上升,而g值却呈现微小的下降趋势。AN与ReichardtET、KosowerZ值之间有线性关系,而与ε、μ却不呈现线性关系。由于ET、Z为模型反应的溶剂微观极性效应参数,而ε、μ为非模型反应的溶剂宏观极性效应参数,所以AN可以作为一种新的非模型反应的溶剂微观极性效应参数。  相似文献   

6.
本文研究了五个吡喃鎓方酸菁染料的溶剂效应,发现最大吸收峰波数υ与函数f(n,ε)存在较好的线性关系,而Bayliss函数项(n2-1)/(2n2+1)决定了吸收光谱的位移变化Δυ,同时还分析了氢键相互作用对理论函数模型的误差.根据染料的聚集动力学证实了染料在正丙醇/水(4:21,体积比)体系中确有二聚体的产生,并发现了两组不同的聚集特性.此外,使用APCIMS质谱技术证实Dye3二氯甲烷浓溶液中也产生了二聚体.  相似文献   

7.
总结了非平衡溶剂化新理论和在量子化学软件Q-Chem中基于含时密度泛函理论(TD-DFT)实现溶剂效应下计算电子吸收和发射光谱的数值解方法.采用该方法计算了染料敏化太阳能电池(DSSCs)中三苯胺型有机染料■在真空和乙腈溶剂中的电子结构与光谱性质,研究发现,π共轭桥上碳碳双键的个数和溶剂效应会促进光电转换.  相似文献   

8.
李群  彭必先 《有机化学》1995,15(3):275-279
将(未)确定的1-(3'-磺酸丙基)2,3,3-三甲基吲哚啉内盐与原乙酸三乙酯在吡啶或酸酐中回流合成了五个氮原子上带有磺酸丙基的取代吲哚碳菁染料. 这些染料和杂环氮原子上带有烷基取代的吲哚碳菁相比, 它们具有较高的熔点, 在极性溶剂中具有较高的溶解度. 这些染料的最大吸收值在540~580nm之间, 并具有较高的消光系数(1~2×10^5L·mol·cm^-^1) .  相似文献   

9.
翟媛萍  杨辉 《化学学报》2007,65(13):1253-1257
通过计算呫吨染料与二苯基碘钅翁盐反应的电子转移参数, 发现荧光黄与二苯基碘钅翁盐反应的热力学驱动力最大, 证明了实现光敏化方式是电子转移反应. 通过对引发体系吸收光谱的研究, 考察了不同价键结构、溶剂效应及引发剂浓度对引发体系吸收光谱的影响, 证实了与C-6位酚氧离子相结合的离子种类很大程度上决定了染料敏化体系的吸收峰强度及峰形状, 溶剂极性增大, 吸收光谱红移; 溶剂极性减小, 其吸收光谱蓝移. 在非极性溶剂中, 引发剂浓度越高, 其解离度越大, 引发剂更多地以自由离子形式存在.  相似文献   

10.
以4-溴-1,8-萘酐为原料,合成脂溶性4-[2-(二甲氨基)乙氧基]-N-十八烷基-1,8-萘酰亚胺。对其进行了1H NMR和IR表征。考察了荧光染料在DMF、乙腈、丙酮、乙酸乙酯和乙醚5种溶剂中的荧光光谱和吸收光谱,发现由于溶剂效应,随溶剂极性由小到大,荧光光谱和吸收光谱的最大峰值波长逐渐红移。考察了不同金属离子和pH对荧光染料荧光光谱的影响,结果表明荧光强度随Fe3+、Zn2+、Co2+浓度增大而逐渐增强,Fe3+的影响最为显著;当pH<7时,荧光强度随着pH的降低逐渐增强;进一步考察了Fe3+、Zn2+、Co2+对吸收光谱的影响,结果发现吸收光谱均蓝移。分析认为荧光染料的光致电子转移被阻碍,实验结果表明,合成的新型荧光染料可用于溶液中金属离子和pH的检测。  相似文献   

11.
This study investigates the effects of irradiation with artificial solar light on the resistance to aging of ethylene-norbornene (EN) copolymer with different solvent dyes and commercial stabilizers. The mechanical properties of the samples were measured before and after ageing using tensile tests. FTIR spectroscopy was used to evaluate the carbonyl index as a measure of photooxidation after irradiation. It was found that the carbonyl index of the samples depended on the type of additive in the composite. Secondary ion mass spectrometry (TOF-SIMS) was used to analyze the chemical composition of the sample surfaces. The degree of oxidative aging was evaluated by measuring the intensities of secondary CxHyOz+ type ions. Samples containing anthraquinone solvent dyes, such as Solvent Blue 97 or Solvent Green 28, showed the most significant improvements in durability in an aging test. Some of the applied solvent dyes showed much greater ability than the studied stabilizers to protect EN films exposed to the full solar spectrum.  相似文献   

12.
Two novel water‐soluble indocyanine dyes were synthesized. Their chemical structures were confirmed by 1H NMR, IR, MS and UV‐vis techniques. The absorptions of the prepared dyes in different solvents were measured. Two dyes exhibited negative solvatochromism, with a blue shift of the absorption and an emission maximum in (bovine serum albumin) protonic solvent relative to non protonic solvent. The fluorescence properties of the dyes in both free state and BSA were investigated. Significant enhancement of the fluorescence intensity for the Dye2 was observed in the presence of BSA. Dye2 could be proposed as fluorescent dyes for BSA detection in aqueous solution.  相似文献   

13.
Absorption and emission spectra of three azo sulfonamide dyes with various molecular structures have been studied in different solvents. The solute photo-physical behavior depends strongly on the solvent-solute interactions and solvent microenvironment. In order to understand the effect of intermolecular interactions on spectral behaviors of these dyes in different solvents and to conceive nature and extent of solvent-solute interactions the spectral variations were analyzed by the linear solvation energy relationships concept. In addition, by means of solvatochromic method the dipole moments of these dyes, in ground and excited states, were investigated.  相似文献   

14.
The solvatochromic properties of the free base and the protonated 5,10,15,20-tetrakis(4-trimethyl-ammonio-phenyl)-porphine tetratosylate (TTMAPP) were studied in pure water, methanol, ethanol, 2-propanol, and their corresponding aqueous mixtures. The correlation of the empirical solvent polarity scale (E T) values of TTMAPP with composition of the solvents were analyzed by the solvent exchange model of Bosch and Roses to clarify the preferential solvation of the probe dyes in the binary mixed solvents. The solvation shell composition effects in preferential solvation of the solute dyes were investigated in terms of both solvent–solvent and solute–solvent interactions and also the local mole fraction of each solvent composition was calculated in the cybotactic region of the probe. The effective mole fraction variation may provide significant physicochemical insights in the microscopic and molecular level of interactions between TTMAPP species and the solvent components and, therefore, can be used to interpret the solvent effect on kinetics and thermodynamics of TTMAPP.  相似文献   

15.
本文通过观察3种咪碳菁类染料在溶液中的聚集行为,从动力学角度分析了影响J 聚集形成的主要因素.  相似文献   

16.
Designed experiments based on a simplex mixture design were employed to explore the effects of three solvent components (water, formic acid, and aqueous acetic acid), extraction time, and extraction temperature for the automated microextraction of basic (cationic) dyes from acrylic fibers. Extractions were conducted by an automated liquid handling system, and dye extraction was evaluated using a UV/visible microplate reader. Highest extraction efficiency for two subclasses of basic dyes (methine and azo) from acrylic fibers was achieved with an extraction solvent containing 88% formic acid/12% water. Cationic dyes were analyzed by capillary electrophoresis using a 45 mM ammonium acetate buffer in acetonitrile–water at pH 4.7. The utility of microextraction combined with capillary electrophoresis–mass spectrometry for analysis of extracts from trace fibers was demonstrated by the detection and characterization of three basic dyes extracted from a 2-mm length of single acrylic fiber.  相似文献   

17.
3-Hydroxychromones (3HC), exhibit dual emissions highly sensitive to solvent properties due to excited state intramolecular proton transfer (ESIPT). Therefore, 3HCs find wide applications as fluorescence probes in biological systems. Here, it is particularly important to understand the fluorescence behaviour of 3HCs in polar environments. Herein, we studied 3-hydroxyflavone, 2-(2-furyl)-3-hydroxychromone and 2-(2-benzofuryl)-3-hydroxychromone in high polarity solvents characterized by different H-bond donor abilities, donor concentrations and acceptor abilities. Our results show that the dual emissions of the dyes are insensitive to solvent basicity but strongly depend on the two other parameters. Moreover, furyl-and benzofuryl-substituted dyes were significantly more sensitive than the 3-hydroxyflavone to H-bond donor ability, while all three dyes showed roughly equivalent high sensitivity to H-bond donor concentration. These results can be explained by different mechanisms. Thus, the sensitivity of all three dyes to increasing concentrations of H-bond donors probably results from increase in the population of solvated dye with disrupted intramolecular H-bonds. Meantime, the sensitivity to H-bond donor ability of the solvent, observed mainly with furyl and benzofuryl dyes, is probably related to the strength of the H-bonds between the solvent and the 4-carbonyl group of the dye with intact intramolecular H-bonds. The present results provide new insights for further applications of 3HC derivatives as environment-sensitive probes and labels of biological molecules.  相似文献   

18.
The steady-state spectral properties (absorption and emission) of three structurally similar Coumarin dyes, C151, C500, and C35 were investigated in 13 different solvents. A Kamlet-Taft (KT) analysis of the spectral peak frequencies reveals that, in addition to polarity, hydrogen bonding between the carbonyl oxygen and a protic solvent in the excited state imparts maximum stabilization for C151 and minimum for C35, while that for C500 lies in between. The spectral properties of the three dyes in two solvents, chloroform and THF, which have similar polarity in the KT scale but have only hydrogen-bond donor (chloroform) and hydrogen-bond acceptor (THF) properties, are seen to be sensitive to the substitution pattern at the 7-amino position. In addition, a slow emission spectral relaxation is observed for C151 and C500 having a time constant of approximately 500 ps in chloroform. For C35 this was too fast to be detected by the time resolution of our setup. The exact reason for this slow spectral relaxation in chloroform is unclear at present, and further studies are needed to understand clearly the structural effects on the hydrogen bonding dynamics of these dyes.  相似文献   

19.
Abstract

The chromatographic characteristics of 42 dyes belonging to different groups have been studied on metal salt-impregnated plates. A suitable separation scheme for the dyes studied and suitable adsorbent system as well as solvent system have been developed.  相似文献   

20.
Chow A  Branagh W  Chance J 《Talanta》1990,37(4):407-412
The sorption of fifty-nine organic dyes, indicators and stains by polyester and polyether-type polyurethane foams was investigated by use of aqueous solutions and powdered foam material. Comparisons were made with sorption from 50% methanol solutions for some dyes and also with solvent extractions done with diethyl ether or ethyl acetate for several dyes. The R(f) values for the dyes run on cellulose TLC plates in water or a mixed solvent mobile phase were compared to the distribution coefficients with polyurethane foam. The relationship between the structure of the test substances and their sorption is discussed.  相似文献   

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