discolouring

Some oil had seeped out, discolouring the grass.

有些油渗出来了，把草地染得变了颜色。

the postage certificates which are contaminated, incomplete or illegible due to fading or discolouring, and stamp patterns cut from stamped envelopes, stamped postcards and stamped aerogrammes shall not be used.

污染，残缺或者褪色，变色，难以辨认的；从邮资信封，邮资明信片，邮资邮简上剪下的邮票图案。

The pipes were beginning to rust, discolouring the water.

管子开始生锈，水都变颜色了。

according to the discolouring between potassium persulfate and light green sf with the anti-catalytic effect of alcohol, a new catalytic spectrophotometry method for the determination of alcohol had been established.

基于乙醇对过硫酸钾与亮绿间的氧化褪色反应的负催化作用，建立了一种定量乙醇的新方法。

dice the apples and toss with a little lemon juice to prevent discolouring.

将苹果切片，和上少许柠檬汁防变色，沥干。

t trace selenium(ⅳ) can catalyze the discolouring oxidization of methylene blue by potassium bromate in nitric acid medium.

在硝酸介质中，硒（Ⅳ）能催化溴酸钾氧化亚甲蓝使之褪色。

technology of preventing copper and its alloys from discolouring

国外铜和铜合金防变色工艺

prevention from discolouring and drying of tsuga

铁杉的防变色及干燥