时间:2019-01-03 作者:英语课 分类:2018年VOA慢速英语(四)月


英语课

Daylight Turns Thin Plastic Barrier into Germ-Killing Material


Daylight-powered germ-killing equipment may someday help protect health workers from deadly microorganisms like Ebola virus disease.


That is a finding from a study published in the journal Science Advances.


Study organizers say they have developed membranes that produce very small amounts of hydrogen peroxide when they are left in sunlight.


Membranes are thin structures that can serve as barriers. They let some things pass through, but other things are blocked. Hydrogen peroxide, a liquid sold in drug stores, works as a disinfectant.


Nearly 500 health workers died in 2014 when Ebola spread through parts of West Africa. Caregivers wear full-body protective suits when they come into contact with patients with infectious diseases. But the process of removing the suits is a time when infection can spread if the surface is covered with microorganisms.


"If there's any live bacteria or virus on the surface, it's still transmissible and could cause infection," said Gang Sun of the University of California, Davis. He is one of the researchers that worked to develop membranes that could cover the outside of protective equipment.


When the chemical molecules on the surface of these membranes are put in sunlight, they react with oxygen in the air to produce small amounts of hydrogen peroxide.


Gang Sun explains that the process creates less hydrogen peroxide than what you would use to remove dirt on clothing, for example. But it is still enough to kill organisms.


Rohan Tikekar is a food scientist with the University of Maryland. He described the development as “quite novel,” or new and different. Tikekar was not involved with the recent study.


He said others have developed materials that produce disinfecting chemicals. But most only work under high-energy ultraviolet (UV) light, and not usual daylight.


The new membrane also works in the dark for at least an hour or two because of chemical properties that can recharge its germ-killing powers. Tikekar called that an important improvement.


Gang Sun said the new membranes could be used for things other than protective gear for health workers. They could also be added to packaging for fruits and vegetables to keep foods fresher and reduce the risk of contamination.


Some versions of the material use natural chemicals. Sun says that one of the next steps is to make it safe to eat.


I'm Jonathan Evans.


Words in This Story


germ – n. an organism known to cause disease


journal – n. a publication, such as a magazine or newspaper


packaging – n. material used to contain something


transmissible – adj. able to be spread to other people


approach – n. a method; a way of doing things


novel – adj. new or unusual


contamination - n. the process of polluting; the act of harming something



学英语单词
17-oxycorticosteroid
additional sum
aecidia
aedoeomyco-dermatitis
aeroembolisms
altitude heading reference system
altizide
amberlike
ambitionists
amentaceous
atmospheric diving suits
atrophie blanche
attached shadow
beckinghams
Bedarrides
bharats
Big Muddy L.
bisabol myrrh
Bratley
buffer mark
build-up area
candidate solution
cut searching method
Cyclobalanopsis subhinoidea
ddh
De-Kastri, Zaliv
densua
dispersive number
distributed operation system
Donec alv. sol. fuerit
dual-wide
DVh
endonasl
engrossing
event pulse
fan-mail
filled with
follow the lead of sb
footballization
fusarium vasinfectum
Girondist
GM_pronouns-reflexive-myself-themselves-etc
greyisher
haire
heavy element radioactive material electromagnetic separator
hump bridge
inexertions
intermittent cavitaion
intrinsic loss
jejunal dumping
kickingly
kurchees
life testing
mackintoshed
mean linear velocity of carrier gas
Minzolum
monitor switch
multiantibiotic
natural increase
Nauclea Korth
nonprotons
nutrient allowance
paramilitary-style
partial discharge range
petasitolone
pillowbook
plastic flow range
pneumalock
poor move
proton aurora
rack-jobbing
rbg
reciprocation pump with unidirectional pistons
reducing atmosphere
Rinópolis
rook rifles
Santa Elena, I.
Saporoshje
scantling draft
secondary rating adjustment
session object
setback buttress
sollys
solstitial tide
step gear weel
steprocket
stockaded
strohmeyer
stroke display
sub-zero weather
surfled
synthetic response matrix
Sālang, Kōtal-e
triliteralism
unclassable
verschuur
violet blue
vitelline duct fistula
Wilson willow
yerker
you are my heart
Zarnestra