chemical 四级考研

Semimetallic chemical element, chemical symbol B, atomic number 5.

半金属学元素，学符号B，原子序数5。

Dyes come from plants or from chemicals.

染料是从植物或学物中得来。

The behavio(u)r of the chemicals was unexpected.

这些学变是出人意料。

These chemicals are practically insoluble in water.

这些学物几乎不溶于水。

Chemically treated hair can become dry and brittle.

经过学处理头发会变得焦脆。

Hydrogen combines chemically with oxygen to form water.

氢和氧合成为水。

Chemicals are used to keep the insects down.

学用于阻止昆虫滋生。

Have you studied the composition of the chemicals?

你研究过这种成分了吗?

As chemical reagent and corrodent of integrated plate.

作学试剂和集成电路电镀板消蚀剂。

The same water was reused after chemical treatment.

原来水经过学处理之后再度使用。

The chemical fertilizer should be well dug in.

学肥料应该均匀地混入土壤中。

What are the chemical reaction characteristics of tropane alkaloids?

氢溴酸东莨菪碱鉴别原理是什么？

Choice having introduced the hammerhead and cleading chemical composition.

介绍了锤头和衬板学成分选择。

To study chemical constituents of hypogeal part from Limonium bicolor.

研究二色补血草地下部分学成分。

Chemical modification including oxygenation, esterify, graft copolymerization and so on.

学性主要有氧、交联、酯和接枝共聚。

The chemical must be salted out and allowed to dry.

必须把这种学物加盐分离出来并让它变干。

We put chemicals in test tubes in our chemistry class.

我们上学课时把学放进试管里。

Certain chemicals can induce undesirable changes in the nervous system.

有些学物能在神经系统中引起不良变。

Chemical analysis of the lymphocele fluid allows differentiation from a urinoma.

由于压迫到肾脏，大淋巴管瘤往往造成血清肌酐上升。

The microorgan-isms employed include mainly chemical conversion bacteria,phototropic bacteria and alga.

学转细菌、向光性细菌和藻类。