The article presents a simultaneous determination method for three kinds of water-soluble dyes: acid red, acid brown and acid black by solving simultaneous equations using a UV-VIS spectrophotometer.

介绍了利用解联立方程组的方法，在紫外可见分光光度计上实现了对酸性红、酸性棕和酸性黑的混合染料中三种成分浓度的同时测定。

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Since 2007, frequent acid rain showers caused by activity at the volcano killed or damaged much of the vegetation to the southwest of the summit, leaving the area brown and orange.

2007年以来由于火山的活动，频繁降下的酸雨破坏了山顶西南部大片植被，并致其死亡，因此在照片上呈现棕色和橘色。

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It mainly grows on yellow soils, acid purplish soils and parts of yellow brown soils.

主要生长在黄壤和酸性紫色土上，黄棕壤上与有分布。

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The stage announcer famously warned people to steer clear of the brown acid.

NPR: Havens, 1st Woodstock Singer, Dies Of Heart Attack

Hands shoot up and the testimonials begin: Antioxidant-loaded XanGo calms acid reflux, cures migraines, chases away brown spots on the skin of someone's mother.

FORBES: Drinking The XanGo