二苯胺重氮盐在乙醇中的光、热分解动力学

二苯胺-4-重氮盐与甲醛的缩聚产物-重氮树脂是制备阴图PS版最重要的感光剂,用它制备阴图PS版已有很多专利^[1-7],但二苯胺重氮盐(包括有类似结构的咔唑重氮盐)光、热分解,文献上还未见有报导。     

四溴化碳-二苯胺成像体系光化学反应的研究

研究了CBr₄-二苯胺(DPA)自由基光敏体系的光化学过程。在250-400nm区,CBr₄的光分解速度随波长的增加而下降。分别用CBr₄、DPA及CBr₄-DPA电荷转移复合物吸收光谱最大值对应的光254、284及333nm辐照CBr₄-DPA体系,发现333nm光辐照有最大的反应速度,证明此体系光激发阶段,CBr₄-DPA生成的基态电荷转移复合物是主要的光敏物质。     

分光光度法测定焦化废水中的吲哚

二苯胺磺酸钠在酸性溶液中遇到NaNO2时,氧化为二苯联苯胺磺酸紫。由于该氧化物不稳定,分解产物再与NO-2发生重氮化反应,加入吲哚后偶合成红色化合物。该化合物最大吸收波长为525nm;摩尔吸光系数为0.57×104L·mol-1·cm-1;线性范围0.053～24mg/L。该化合物至少稳定1h,焦化废水中存在的其它物质不干扰吲哚测定,样品的回收率为98.8%～102%。     

A highly efficient antioxidant based on boron and a Schiff base bridged phenolic diphenylamine: synthesis,crystal structure and thermal and antioxidant properties

Antioxidants can effectively protect vegetable‐oil‐based lubricants against oxidative degradation and prolong their service life. A novel compound, (E)‐4‐({3,5‐di‐tert‐butyl‐2‐[(diphenylboranyl)oxy]benzylidene}amino)‐N‐phenylaniline (BSPD) or {2‐[(4‐anilinophenyl)iminomethyl‐κN]‐4,6‐di‐tert‐butylphenolato‐κO}diphenylboron, C₃₉H₄₁BN₂O, was synthesized by a one‐pot reaction of the Schiff base bridged phenolic diphenylamine 2,4‐di‐tert‐butyl‐6‐{N‐[4‐(phenylamino)phenyl]carboximidoyl}phenol (SPD) with phenylboronic acid. The corresponding single‐crystal X‐ray study revealed that the B atom in BSPD has a typical tetrahedral geometry, and the N,O‐chelated six‐membered ring adopts a chair conformation. According to thermogravimetric analysis, the 5% weight‐loss temperature of BSPD increases to 328 °C and the 95% weight‐loss temperature is up to 414 °C. More importantly, the antioxidant capability of BSPD in vegetable oil is much better than that of commercial antioxidants [diphenylamine (DPA) and 2,6‐di‐tert‐butyl‐4‐methylphenol (BHT)] and unmodified SPD.     

Electropolymerized Diphenylamine on Functionalized Multiwalled Carbon Nanotube Composite Film and Its Application to Develop a Multifunctional Biosensor

Diphenylamine (DPA) monomers have been electropolymerized on the amino‐functionalized multiwalled carbon nanotube (AFCNT) composite film modified glassy carbon electrode (GCE) by cyclic voltammetry (CV). The surface morphology of PDPA‐AFCNT was studied using field‐emission scanning electron microscopy (FE‐SEM). The interfacial electron transfer phenomenon at the modified electrode was studied using electrochemical impedance spectroscopy (EIS). The PDPA‐AFCNT/GCE represented a multifunctional sensor and showed good electrocatalytic behavior towards the oxidation of catechol and the reduction of hydrogen peroxide. Rotating‐disk electrode technique was applied to detect catechol with a sensitivity of 1360 µA mM^?1 cm^?2 and a detection limit of 0.01 mM. Amperometric determination of hydrogen peroxide at the PDPA‐AFCNT film modified electrode results in a linear range from 10 to 800 µM, a sensitivity of 487.1 µA mM^?1 cm^?2 and detection limit of 1 µM. These results show that the nano‐composite film modified electrode can be utilized to develop a multifunctional sensor.     

A Comparison of Four Frequently Used Assays for Quantitative Determination of DNA

Abstract

Four frequently used DNA determination methods are compared:the diphenylamine colorimetric assay and three fluorescent stain methods, i.e. diaminobenzoic acid diaminophenylindole and bisimidazole (Hoechst 33258). Interference with these assays by thirty-five substances, on different DNA preparations, are examined. The classical diphenylamine method is found to be the most reliable of all, closely. followed by diaminobenzoic acid staining. The remaining two methods, although very sensitive, perform rather poorly.     

邻偶氮萘醌磺酸基为负离子的二苯胺—4—重氮盐：———甲醛树脂的制备与性质

二苯胺－４－重氮盐与邻偶氮萘醌磺酸酯均具有很高的光敏性，分别是阴图型和阳图型预涂感光印刷版（ＰＳ版）的感光剂，用它们制备阴图型和阳图型ＰＳ版已有很多专利报道．重氮基与邻偶氮萘醌基的光分解分属两种类型，前者的中间体为自由基或正离子［１，２］，后者为碳卡...     

PHOTOPHYSICS STUDIES OF ORGANIC COMPOUNDS——NANOSECOND LASER PHOTOLYSIS AND TRANSIENT ABSORPTION SPECTRA STUDIES OF PYRENE-AROMATIC AMINES

Nanosecond time-resolved transient absorption spectra of pyrene-triphenylamine, pyrenediphenylamine, pyrene-N, N-dibenzylaniline systems in various solvents have been investigated. In nonpolar solvent, pyrene-triphenylamine exciplex and pyrene-N, N-dibenzylaniline exciplex were observed directly. In acetonitrile, the pyrene anion radical, triphenylamine and diphenylamine cation radicals were detected. On the basis of the present experimental facts, the mechanism of fluorescence quenching processes of pyrene in polar and nonpolar solvents has been established.     

二苯胺重氮树脂在不同溶剂中的分解动力学

非银盐感光材料不但可以用于成像过程 ,而且还在印刷油墨、光敏抗蚀、涂料、粘合剂等方面得到应用。二苯胺重氮树脂是阴图 PS版最重要的感光剂 [1] ,关于它的应用已有许多报道 [2～ 7]和专利 [8,9]。作为一种预图感光版 ,要求感光性能好 ,储存期在一年以上。重氮化合物一般都亲水并存在暗反应 (即热反应 ) ,用它制成的 PS版易受温度和湿度的影响。二苯胺重氮盐在乙醇中的光、热分解文献已有报道 [10 ] ,但作为感光材料的二苯胺重氮树脂在水、乙醇 -水、甲醇 -水溶剂中的光、热分解动力学研究尚无报道。本文用分光光度法对二苯胺重氮树脂在…