The purity of DBC-chlorophosphonazo was checked by chromatography and a single blue band was obtained for the pure product.

用层析法检验DBC-偶氮氯膦，纯产品只有一个单一的蓝色斑点。

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But nobody woke up and things stayed violet, all except for a single blue Jay who hadn't changed color and stayed the brightest blue.

但是没有人从梦中醒来，万物依然是紫色。只有一只冠蓝鸦没有变色，仍旧是最鲜艳的蓝色。

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A single pale blue flower grows up from each joint on a long stalk.

一根长梗的每个节上都长出了一朵淡蓝色的花。

《柯林斯英汉双解大词典》

There have been commercial hurdles: Gale has so far nailed not a single blue-chip tenant.

FORBES: Scratch Builders

David Miliband: No, I haven't got a single blue-print for the country.

BBC: Politics Show, Sunday 23 October 2005

It's palm-sized with a single blue LED light indicating a connection, but honestly you don't ever need to look at it: it doesn't need line-of-sight to your handset because it uses a wireless protocol called WiFi Display, which means you can happily leave it dangling out of the way behind your TV.

ENGADGET: AllShare Cast wireless streaming dongle for Samsung Galaxy S III -- hands-on (video)