您要查找的是不是：
- chemical weed killers 化学除莠剂
- chemical weed killer 化学除草剂
- Tell people why it is harmful to use insecticides and weed killers. （一）告诉人们使用杀虫剂，除草剂等化学药品是如何有害。
- The grass on the lawn grows wildly, we must use some weed killer. 这片草地的草长得太杂了，我看要用些除草剂了。
- Tell people why it is harmful to use insecticides and weed killers . （一）告诉人们使用杀虫剂，除草剂等化学药品是如何有害。
- You need a selective weed killer that won't damage your garden flowers. 你需要一种精选的除草剂，不会伤害你花园的花。
- Modern weed killers are put in two categories, selective (affecting specific plant species) and nonselective (affecting plants generally). 现代的除草剂可分为两类:选择性的（仅对特定的植物有效）及非选择性的（作用及于各种植物）。
- A colorless,sweet-smelling,mobile liquid,C4H3OCHO,made from corncobs and used in the synthesis of furan,as a solvent for nitrocellulose,and as a fungicide and weed killer. 糠醛，一种用于合成呋喃的由玉米棒芯制成的无色、发甜味的流性液体，C4H3OCHO，可作纤维素溶剂、灭真菌剂及除草剂。
- Integrating this technology with chemical weed control,the practice suited to mechanization,and saved energy with improved yield. 该技术与化学调控和化学除草技术相配套,适于机械化作业,达到节能高产的目的。
- A colorless, sweet-smelling, mobile liquid, C4H3OCHO, made from corncobs and used in the synthesis of furan, as a solvent for nitrocellulose, and as a fungicide and weed killer. 糠醛一种用于合成呋喃的由玉米棒芯制成的无色、发甜味的流性液体，C4H3OCHO，可作纤维素溶剂、灭真菌剂及除草剂
- Now, a growing number of weeds are developing resistance to the world's most popular weed killer. 现在，数量日益增长的一些杂草下大对世界上最受欢迎的除草剂产生抗体。
- For instance, those who grow herbicide-tolerant soybeans typically avoid the most noxious weed killer, turning instead to glyphosate herbicides, which are less toxic and degrade more quickly. 例如，农人要是种植了耐除草剂的大豆，就会避免使用最毒的杀草剂，而改用毒性弱、分解快的苷磷除草剂。
- Three pyridine class weed killer 均三氮苯类除草剂
- (4-chloro-2-methylphenoxy)acetic acid(weed killer) 4-氯-2-甲基苯氧基乙酸
- 2-methyl-4-chlorophenoxyacetic acid(weed killer) 2-甲基-4-氯苯氧乙酸
- a colorless salt (NaClO3) used as a weed killer and an antiseptic 一种无色的盐（NaClO），用作除草剂和防腐杀菌剂
- A reactor is a container for chemical reaction. 反应器是进行化学反应的容器。
- The chemical symbol for copper is "Cu". 铜的化学符号是Cu。
- We are doing a chemical experiment. 我们正在做化学实验。
- a colorless salt (NaClO3) used as a weed killer and an antiseptic. 一种无色的盐（NaClO），用作除草剂和防腐杀菌剂。
