4- Tert-butyl-1-(4'-dimethylaminobenzylideneamino)pyridinium perchlorate (BDPP) is a novel dye showing unusual properties, viz. (i) it gives a yellow-green fluorescence which quenched on heating and in solution, and (ii) by heating at 180° or by simple squeezing, it is transformed into orange, non-fluorescent crystals (i.e. it is piezochromic). Surprisingly, among other 1- (benzylideneamino) pyridinium salts, BDPP was the only dye revealing the above properties.

中文翻译：

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4-叔丁基-1-（4'-二甲基氨基-亚苄基氨基）高氯酸吡啶鎓（BDPP）：一种新型荧光染料

4-叔丁基-1-（4'-二甲基氨基亚苄基氨基）高氯酸吡啶鎓（BDPP）是一种新颖的染料，显示出不同寻常的特性，即。（i）发出黄绿色荧光，该荧光在加热和在溶液中淬灭，和（ii）通过在180°加热或通过简单挤压将其转变为橙色的非荧光晶体（即为压致变色的）。令人惊讶地，在其他1-（亚苄基氨基）吡啶鎓盐中，BDPP是唯一显示出上述性质的染料。