时间:2019-01-14 作者:英语课 分类:VOA标准英语2015年(八月)


英语课

Researchers: New Nanoparticles May Replace Chemicals in Pesticides 1 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 fungi 2 and bacteria that attack crops, and others such as e. coli that are harmful to humans.


Among the most potent 3 elements of modern pesticides - and even some antibiotics 4 - are silver-based nanoparticles, which attach to microbes and destroy them. But as those nanoparticles degrade, they release the silver from their metallic 5 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 hygiene 6 items.



n.杀虫剂( pesticide的名词复数 );除害药物
  • 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》
n.真菌,霉菌
  • 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。
adj.强有力的,有权势的;有效力的
  • 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。
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 )
  • 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。
adj.金属的;金属制的;含金属的;产金属的;像金属的
  • 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。
n.健康法,卫生学 (a.hygienic)
  • 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。
学英语单词
acquired hydromyelia
agreed service time
amicable consultation
amour propres
an anus
as safe as houses
atactic agraphia
atchievements
bouake
brush mark
carry the war into the enemy's country
carybdeids
contents retrieval
continuous vulcanization
Corydalis petrophila
counterindicate
crystal mic
curateships
cyclopaedias
determinant of a matrix
dipropyl sulfate
direct loading
domestic affairs
domestic arbitral
drak
dreames
drownin'
dyce
electricweld
embryonal rhabdosarcomas
erythrosines
faces-off
fertile assembly
film equipment
flowing pressure
fluidtight
folded thrust
formule
germ free milk
Greek alphabet
heteromatic chemistry
hyperfluid
inferior leaf
inspection of rat evidence
insurmountably
karbovanets
kiss good - bye
lead-screw driving
Leutenberg
light weight hide
Listerizing
livening up
lound
maritime distress manoeuvring
maternal relative
Maya-Maya
mayo
military neutrality
monolithic boundary layer capacitor
mtg.
multivariate
mutator gene (demerec 1937)
mylohyoid artery
negroids
nodules tabac
oceanic front
operating readiness
outplacements
p-over port
palaestina
pallasites
petal dress
photoelectric peak
phytogenetical
polke
prepicked
print-forms
products incorporated CD
professional indemnity
Pseudosphaeriales
Puccinia dianthi-japonici
Rawmarsh
reading instruction
retrenchment
roller pusher
sculping
sequential construct
South Hd.
speed change control
standard color chart
Staurastrum
stiffening
subscriber's drop line
thanom
Thiruvananthapuram
trienynol
tuminensis
ulcerative lymphangitis
uneagerly
veggiedogs
wind tunnel
X-ray emission analysis