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
adjuvanticity
after-cultivation
airphoto transfer
alpine glaciation
amphisapropel
ampullae quininae et ureae hydrochloridi
angiport
antifreeze substance
arch-thief
argies
assembly coding
automatic-batch column dryer
background noise of wind tunnel
blank bond
blanket jam
bretcock
canvas table
caserne
centipeds
cerinous
cesium tetraoxide
chloro-stannate
counter immunoelectrophoresis
counter-ideologies
cryopanel array
cutting room
Cystophora cristata
derisking
drawing vehicle
Ellwangen Berge
epidemic strain
Europistan
excercise therapy for amputees
excess credit
fair warning
godowns
grunters
hongkongia songi
Hubbard.
hyparchic gene
IAPSO
informal application
intensity fluctuation spectroscopy
internal normalization
inverter
jahn teller effect
jainer
k/l ratio
Karacorman
Kirk Sound
Komis
Lachlan
lafeu
laryngomalacia
let fall a remark
level of interpenetration
libtardation
lot-acceptance sampling
lunar mansion
madreperla lustre
mains-frequency synchronous motor
methoxycinnamate
NCA-Snase
Nhanduqué, R.
nitrex
North Palisade Mountain
nothing to
on the periphery
on-site reprocessing
one piece frame press
optical fiber communications
pectorophony
plastic corpuscle
Platanthera stenoglossa
polyazulene
reverse osmosis device
robe-de-chambre
rose pinks
scaled pulse
shambhala
simulatneous draw texturing machine
soil buffer action
specialdelivery
squeeze-
supermans
suprascapular region
sweet ferns
tachylytic
tackifying ability
thingama-bob
tomorrers
track drainage
transliteration
Turyn's sign
vat-free
Victoria violet
vision acuity
volatile metal
weighing house
wymore
ZPO