Thermal annealing effects on synthetic melanin

被引：6

作者：

Gonçalves, PJ ^{[1
]}

Brunello, CA ^{[1
]}

Graeff, CFO ^{[1
]}

机构：

[1] USP, DFM, FFCLRP, Ribeirao Preto, Brazil

来源：

MOLECULAR CRYSTALS AND LIQUID CRYSTALS | 2002年 / 374卷

关键词：

melanin; ESR; water; thermal annealing;

D O I：

10.1080/713738300

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The influence of adsorbed moisture on the ESR signal of the free radical in synthetic melanin is investigated. Water is found to correspond to 10% to 20% of melanin mass in the as synthesized state. Water removal is responsible for an increase in spin density induced by extended heating at temperatures above 60 degreesC. This enhanced spin concentration is stable at room temperature but can be quenched by rehydratation. A systematic study on the time dependence of the spin enhancement is presented along with a macroscopic model based on rate equations.

引用

页码：39 / 44

页数：6