Electron Transfer and Proton Transfer in Supramolecular Systems

本论文共分五章。 第一章为绪论，介绍光诱导电子转移(PhotoinducedElectronTransfer，PET)对于认识生物动态过程的重要意义及该领域中已取得的一些令人激动的研究成果，包括(1)氢键在调节长距离电子转移过程的功能性作用；(2)α-螺旋肽偶极产生的内电场对电子转移速率常数的影响；(3)简介了一些复杂的生物模拟体系，利用PET作为能源趋动合成ATP；(4)质子偶合电子转移(PCET)的理论模型及发展趋势。主要评述PET理论和实验工作的新进展，探讨当前的发展动向，并提出论文设想。 第二章主要研究基于氢键的PCET荧光传感，分两节。如何将PCET从反应机理发展为分析学科荧光检...This dissertation consists of five chapters. In Chapter One, highlights of new findings in electron transfer studies, in which elegant synthetic model systems were used to address important fundamental questions, were briefly described. The main examples include: (1) efficient long distance electron transfer mediated by hydrogen bonds; (2) the influence of internal electric fields on the rate ...学位：理学博士院系专业：化学化工学院化学系_分析化学学号：B19992500

Dual Fluorescence from Aqueous 1-Naphthylamine Solutions of High pH ——Excited-State Acidic Dissociation of Naphthylamine

Dual fluorescence at ca. 447 nm and 545 nm w as observed from the aqueous 12naph thylam ine (NA ) solutions at pH h igher than 1316. Sim ilar dual fluorescence was also found w ith sodium12naph thylam inoacetate (NAA ) , but not w ith N , N 2disubstituted 12am inonaph thalenes such as sodium 12 naph thylam inodiacetate (NADA ) and 12dimethylam inonaph thalene (DMAN ). No change in absorption spectra of NA and NAA w as observed in th is pH region. It w as p roposed that the dual fluorescence ob2 served w ith NA and NAA w as due to the excited state dissociation of the p rimary and secondary am ines at h igh pH. F rom the dual fluorescence intensity ratio pH titration curve, the pK 3 ’ a s of NA and NAA w ere estimated to be betw een 14 and 15 w h ich aremuch low er than the ground state pK a. The novel app roatch is such a simp le, convenient and frequent analysis technique that it can bew idely used in detecting the sub2stitutional derivatives of am inonaph thalene.教育部优秀年轻教师基金(批准号 :教人司 2 0 0 0 -11);国家自然科学基金(批准号 :29975023)

Dual fluorescence from aqueous 1-naphthylamine solutions of high pH - Excited-state acidic dissociation of naphthylamine

Dual fluorescence at ca. 447 nm and 545 nm was observed from the aqueous 1-naphthylamine (NA) solutions at pH higher than 13.6. Similar dual fluorescence was also found with sodium 1-naphthylaminoacetate(NAA), but not with N, N-disubstituted 1-aminonaphthalenes such as sodium 1-naphthylaminodiacetate (NADA) and 1-dimethylaminonaphthalene (DMAN). No change in absorption spectra of NA and NAA was observed in this pH region. It was proposed that the dual fluorescence observed with NA and NAA was due to the excited state dissociation of the primary and secondary amines at high pH. From the dual fluorescence intensity ratio pH titration curve, the pK(a)(.)'s of NA and NAA were estimated to be between 14 and 15 which are much lower than the ground state pK(a). The novel approach is such a simple, convenient and frequent analysis technique that it can be widely used in detecting the substitutional derivatives of aminonaphthalene

高铝粉煤灰铝硅化合物在稀碱溶液中的浸出行为

研究了循环流化床锅炉高铝粉煤灰中铝和硅在NaOH稀溶液中的浸出行为,在对高铝粉煤灰的组成、物相等物化性质研究的基础上,考察了碱浓度、反应温度和反应时间等工艺参数对粉煤灰中铝硅反应性能的影响.结果表明,粉煤灰为大小不一的不规则颗粒,疏松多孔,具有较高的反应活性;在温和条件下,碱溶液中铝硅溶出规律存在较大差异,在95℃、碱浓度为150g/L、反应90min时二者差异最大,SiO2溶出率可达23.15%,而Al2O3的溶出率仅为1.68%,粉煤灰的铝硅比可由0.78提高到0.99

高铝粉煤灰铝硅化合物在稀碱溶液中的浸出行为

研究了循环流化床锅炉高铝粉煤灰中铝和硅在NaOH稀溶液中的浸出行为,在对高铝粉煤灰的组成、物相等物化性质研究的基础上,考察了碱浓度、反应温度和反应时间等工艺参数对粉煤灰中铝硅反应性能的影响.结果表明,粉煤灰为大小不一的不规则颗粒,疏松多孔,具有较高的反应活性;在温和条件下,碱溶液中铝硅溶出规律存在较大差异,在95℃、碱浓度为150g/L、反应90min时二者差异最大,SiO2溶出率可达23.15%,而Al2O3的溶出率仅为1.68%,粉煤灰的铝硅比可由0.78提高到0.99

高铝粉煤灰在碱介质中的脱硅反应动力学研究

以循环流化床高铝粉煤灰为研究对象,研究了粉煤灰在低温中等浓度氢氧化钠溶液中的脱硅反应动力学。研究结果表明,粉煤灰碱溶脱硅反应过程符合液-固多相反应的内扩散控制模型,表观反应级数为0.015,反应表观活化能为14.80 kJ/mol

高铝粉煤灰铝硅化合物在稀碱溶液中的浸出行为

研究了循环流化床锅炉高铝粉煤灰中铝和硅在NaOH稀溶液中的浸出行为,在对高铝粉煤灰的组成、物相等物化性质研究的基础上,考察了碱浓度、反应温度和反应时间等工艺参数对粉煤灰中铝硅反应性能的影响.结果表明,粉煤灰为大小不一的不规则颗粒,疏松多孔,具有较高的反应活性;在温和条件下,碱溶液中铝硅溶出规律存在较大差异,在95℃、碱浓度为150g/L、反应90min时二者差异最大,SiO2溶出率可达23.15%,而Al2O3的溶出率仅为1.68%,粉煤灰的铝硅比可由0.78提高到0.99

Intramolecular Charge Transfer and Electron Transfer in N-(1-Naphthyl)aminoacetic Acid in Aqueous Solution

pH titration of the fluorescence of N-(1-naphthyl)aminoacetic acid(NAA) was performed in aqueous solution over pH range of 1 5â 12 5. Despite no shift in the fluorescence maximum wavelength, the titration curve showed an Ω-shaped profile with increasing pH with two inflection points at pH 4 1 and pH 11 5, respectively. These values correspond to the excited-state pK *_a î ±s of carboxylic group and ammonium cation, respectively, which are both higher than those of the corresponding ground-state pK_as of 2.64 and 11.83,of which the former changes more.The substantial weakening of the proton dissociation of carboxy lic group in the excited state should be indicative of the decrease in the inductive +I-effect of the ammonium cationat the B-position due to the excited-state intramolecular charge transfer from naphthalene moiety to ammonium.The latter was also confirmed by the slight increase inthe exited-statepK*a2. The fact that the increase inpK*a1is larger than that in pK*a2 suggests that the effect of the intramolecular charge transfer on the involved moiety be weaker than that on are motemoiety in the samespecies.This could be taken into consideration for designing means of tuning the structures and properties of peptide andp roteinvia photo-excitation.It was identified that the NAAzwitterion(â ¡)was the emissivespecies.The fluorescence quenching at high pH was assumed to be due to the photoinduced intramolecular electron transfer between carboxy late anion and the excited naphthalene moiety.The present caserep resents an example in which both in -tramolecular charge transfer and electron transfer occur to shape the pH titration profile.教育部优秀青年教师基金;留学回国人员基金;德国洪堡基金

Dual Flrorescence of Anilino Substituted Benzanilides in Non-polar Solvent Cyclohexane——Direct Spectroscopic Evidence for the Excited-state Charge Transfer

The f luo rescence spect ra in cyclohexane of a series of benzan ilides (BA s) with different p a ra2sub st ituen t s at the an ilino mo iety revealed that BA s em it ted dual f luo rescence, w ith one no rm al w eak em ission at ca. 330 nm and an abno rm ally long2w avelength em ission ranging f rom 460 to 550 nm. The long2w avelength em ission w as found st rongly dependen t of the elect ron donat ing capacity of the sub st ituen t at the an ilino mo iety and a st ronger elect ron donat ing sub st ituen t led to a red2sh if t in the em ission. The energies of the long2w avelength em ission of the BA s w ere co rrelated to the ox ida2t ion po ten t ials of the dono rs, EDöD + , and a n ice linear co rrelat ion w as found w ith a slope of + 0166, w h ich clearly po in ted to the charge t ran sfer character of the em issive state fo r the long2w avelength e2 m ission and the h igh decoup ling ex ten t of the charges in the CT state. Th is is the f irst repo rt that show s the direct evidence fo r the CT natu re. The resu lt sm igh t be of sign if icance in understanding the photophysics of pep t ide and p ro tein and in designing novel fluorescent chemosensors.国家自然科学基金 (批准号 :2 9975 0 2 32 0 175 0 2 0 );教育部优秀青年教师奖励计划 (2 0 0 1年 );德国大众基金 (批准号 :I/770 72 )资助

Intramolecular charge transfer and electron transfer in N-(1-naphthyl) aminoacetic acid in aqueous solution

pH titration of the fluorescence of N-(1-naphthyl)aminoacetic acid(NAA) was performed in aqueous solution over pH range of 1.5-12.5. Despite no shift in the fluorescence maximum wavelength, the titration curve showed an Omega -shaped profile with increasing pH with two inflection points at pH 4.1 and pH 11.5, respectively. These values correspond to the excited-state pK(a)*'s of carboxylic group and ammonium cation, respectively, which are both higher than those of the corresponding ground-state PKa' s of 2.64 and 11.83, of which the former changes more. The substantial weakening of the proton dissociation of carboxylic group in the excited state should be indicative of the decrease in the inductive + I-effect of the ammonium cation at the beta -position due to the excited-state intramolecular charge transfer from naphthalene moiety to ammonium. The latter was also confirmed by the slight increase in the exited-state pK(a2)*. The fact that the increase in pK(s1)* is larger than that in pK(a2)* suggests that the effect of the intramolecular charge transfer on the involved moiety be weaker than that on a remote moiety in the same species. This could be taken into consideration for designing means of tuning the structures and properties of peptide and protein via photo-excitation, It was identified that the NAA zwitterion( Il) was the emissive species. The fluorescence quenching at high pH was assumed to be due to the photo-induced intramolecular electron transfer between carboxylate anion and the excited naphthalene moiety. The present cask represents an example in which both intramolecular charge transfer and electron transfer occur to shape the pH titration profile