VOA标准英语2015--研究人员表示新的纳米粒子可能取代化学农药

Researchers: New Nanoparticles May Replace Chemicals in Pesticides¹ 研究人员表示新的纳米粒子可能取代化学农药

Using pesticides to battle harmful bacteria that attack fruit and vegetables has its downside, releasing harmful chemicals onto the crops and into the environment. Scientists at the North Carolina State University say they may be able to replace those chemicals with a new type of eco-friendly nanoparticles.

Large farms use various chemicals to fight fungi² and bacteria that attack crops, and others such as e. coli that are harmful to humans.

Among the most potent³ elements of modern pesticides - and even some antibiotics⁴ - are silver-based nanoparticles, which attach to microbes and destroy them. But as those nanoparticles degrade, they release the silver from their metallic⁵ core, which may be harmful.

“The effects are not, potentially maybe not so good for environment or human ingestion, so the problem is how do you potentially remove that danger from engineered nanomaterials,” said Orlin Velev, a professor of chemical and biomolecular engineering.

Velev and Ph.D. student Alexander Richter discovered that silver-based nanoparticles can be replaced with non-harmful nanoparticles based on an organic polymer called lignin, naturally found in most plants.

Such nanoparticles, designated as EbNPs, also carry highly active silver ions that attach to and kill bacteria, but their core is biodegradable and not harmful to the environment.

“By doing so, we could actually make the nanoparticles keep their functionality but make them degradable while also reducing the amount of the silver core in the nanoparticle system,” Richter said.

Based on their research, Velev and Richter founded a start-up company that will continue developing the method for industrial-grade production.

“We believe that this can lead to a new generation of agricultural treatment products, that they're going to be more efficient, that they're going to use less chemicals, and that they're going to be more friendly toward the environment,” Velev said.

They say their biodegradable nanoparticles could also be used in consumer products such as disinfectants and personal hygiene⁶ items.

1 pesticides   

n.杀虫剂( pesticide的名词复数 )；除害药物

参考例句：

• vegetables grown without the use of pesticides 未用杀虫剂种植的蔬菜
• There is a lot of concern over the amount of herbicides and pesticides used in farming. 人们对农业上灭草剂和杀虫剂的用量非常担忧。 来自《简明英汉词典》

2 fungi   

n.真菌，霉菌

参考例句：

• Students practice to apply the study of genetics to multicellular plants and fungi.学生们练习把基因学应用到多细胞植物和真菌中。
• The lawn was covered with fungi.草地上到处都是蘑菇。

3 potent   

adj.强有力的，有权势的；有效力的

参考例句：

• The medicine had a potent effect on your disease.这药物对你的病疗效很大。
• We must account of his potent influence.我们必须考虑他的强有力的影响。

4 antibiotics   

n.（用作复数）抗生素；（用作单数）抗生物质的研究；抗生素，抗菌素( antibiotic的名词复数 )

参考例句：

• the discovery of antibiotics in the 20th century 20世纪抗生素的发现
• The doctor gave me a prescription for antibiotics. 医生给我开了抗生素。

5 metallic   

adj.金属的；金属制的；含金属的；产金属的；像金属的

参考例句：

• A sharp metallic note coming from the outside frightened me.外面传来尖锐铿锵的声音吓了我一跳。
• He picked up a metallic ring last night.昨夜他捡了一个金属戒指。

6 hygiene   

n.健康法，卫生学 （a.hygienic）

参考例句：

• Their course of study includes elementary hygiene and medical theory.他们的课程包括基础卫生学和医疗知识。
• He's going to give us a lecture on public hygiene.他要给我们作关于公共卫生方面的报告。