时间:2019-02-23 作者:英语课 分类:英语时差8,16


英语课

 A long wait, on this Moment of Science.   You might have heard the old adage 1 that glass is a liquid, and if you go over to Europe and look at the stained glass windows in the cathedrals, you'll find them thicker on the bottom than the top because they are gradually spilling out. Is this true?


Before we answer that one, let's take a second to think about what a cool image that is. Maybe if you lived for centuries instead of years, you could sit around and watch glass pour the way we watch molasses ooze 2 out of a jar.
Well, sometimes little factoids like this get passed around that may or may not be accurate. So, to set the record straight, glass is indeed a very slow-moving liquid -- yep! -- given the standard definition of a liquid, which is something that takes the shape of its container. If you could wait a really, really long time, you might be able to watch a seemingly-solid piece of glass do this.
But it would take a lot more than a few centuries. In fact, a recent study by Edgar Zanotto in the American Journal of Physics showed that the amount of time you'd have to wait to see glass change its shape with the naked eye would be longer than the age of the universe! Those cathedral windows are probably thicker in some places just because of the crude methods used to form them.
So, yes, technically 3 glass is a liquid, but no, you can't ever see it move. Unless you have a few billion years to kill.  

n.格言,古训
  • But the old adage that men grow into office has not proved true in my experience.但是,根据我的经验,人们所谓的工作岗位造就人材这句古话并不正确。
  • Her experience lends credence to the adage " We live and learn!"她的经验印证了一句格言: 活到老,学到老!
n.软泥,渗出物;vi.渗出,泄漏;vt.慢慢渗出,流露
  • Soon layer of oceanic ooze began to accumulate above the old hard layer.不久后海洋软泥层开始在老的硬地层上堆积。
  • Drip or ooze systems are common for pot watering.滴灌和渗灌系统一般也用于盆栽灌水。
adv.专门地,技术上地
  • Technically it is the most advanced equipment ever.从技术上说,这是最先进的设备。
  • The tomato is technically a fruit,although it is eaten as a vegetable.严格地说,西红柿是一种水果,尽管它是当作蔬菜吃的。
学英语单词
-central
a curtain raiser
acetylgitaloxin
Ambocythere
annual audit
avantgardes
away from keyboard
Bourdon's test
burnettizes
Bénévent-l'Abbaye
cataract surgery
checker supporting column
cicatricial alopecia
Consultation Shipping Group
data country code
data technique
debt problem
decoratifs
design low flow year
dipropyl maleate
directional current metre
DNase
end - of - life care
Favier explosives
fluid cast
form of title block
green markets
hard a-weather
histoleucocyte
hospital administrator
hypothalamic syndrome
ideal perfect-crystal
indefinite chill roll
intake flow velocity
intermits
investigator-initiated
iron-dust disease
JRCERT
kristall
Lampedusa
Littlebourne
los inocente
maintenance time limit
majorizer
Mamedkala
Monarda citriodora
multicomponent polymerization
NatCen
negating
non-stationary thermal conductivity
nonpecuniary
notice clause
NSC-69856
oversubsidize
paper low indicator
pitch in
post industrial society
pre-chemical
primary boiling
prod-contact magnetization
Prometheus-type
quantity factor
quantity purchased
Rathcoole
re-emphasised
recaldes
red flour beetle
remarkable theorem
retroperitoneallymphocele
rivalships
salt temperature
sea-water battery
sediment runoff
semi-structured? interview
service office
session level field
shunt inductor
skip mackerel
slash off
solar X-ray burst
South American leishmaniasis
sph(a)eroid
surface infection
swivel wheel head
take a whack at
talinum calycinums
Tapping Chucks
teeth-chattering
tetrapodomorph
the West Coast
tihuanaco
transverse sinus of pericardium
triaxial compressive strength
undistempered
Urner Alpen
venae sacralis media
vital energy
were of little value
wodanium
wood gas
wound-up company
Yellala Falls