[化] 氟化氢铵

This is Scientific American's 60-Second Science. I'm Karen Hopkin. This will just take a minute. Beauty is only skin deep. And the beauty of shiny white teeth is even less deep. Because a new study shows that fluoride forms a thinner protective shiel

发表于:2018-12-02 / 阅读(125) / 评论(0) 分类 Scientific American(十二)月

The composition of the sun lies in this bar code. 这个条码说明了太阳的组成 All the thin lines are caused by tiny amounts of complex elements 这些细细的线条,都是微量复杂元素造成的 metals like iron and magnesium. 好比说

发表于:2018-12-07 / 阅读(127) / 评论(0) 分类 太阳科普

07 牙病的预防与治疗 DATE=2-27-01 TITLE=SCIENCE IN THE NEWS #2113 - (1)Dental Health BYLINE=Nancy Steinbach VOICE ONE: This is Sarah Long. VOICE TWO: And this is Bob Doughty with Science in the

发表于:2018-12-07 / 阅读(92) / 评论(0) 分类 科技之光

Broadcast: February 14, 2003 By George Grow This is the VOA Special English Environment Report. President Bush has offered a plan to speed development of technology that uses hydrogen as fuel. His goa

发表于:2018-12-07 / 阅读(127) / 评论(0) 分类 VOA2003(上)-科技导航

In business, Optus has called for Telstra's proposals on its participation in the national broadband network to be blocked. Optus' chief executive Paul O'Sullivan says Telstra's current plan for the separation of its retail and wholesale arms wholesa

发表于:2018-12-11 / 阅读(107) / 评论(0) 分类 澳洲ABC新闻快递2011年

I am speaking not as a Briton, not as a European, not as a member of a western democracy, but as a human being, a member of the species Man, whose continued existence is in doubt. The world is full of conflicts: Jews and Arabs; Indians and Pakistanis

发表于:2018-12-12 / 阅读(94) / 评论(0) 分类 英语演讲

Is it necessary to have cavities in the baby teeth repaired? 乳牙蛀成了洞还有必要补上吗? If the baby teeth are going to fall out, I don't think that it matters if they become decayed. 如果乳牙是要脱落的,我想蛀了也没有关

发表于:2018-12-27 / 阅读(124) / 评论(0) 分类 口腔临床英语对话

This is Scientific Americans 60-Second Science. I am Cynthia Graber. This will just take a minute. Solar panels typically convert sunlight into electricity or heat. But photosynthetic vegetation converts sunlight into chemical energy. Now M.I.T.s Dan

发表于:2019-01-04 / 阅读(107) / 评论(0) 分类 Scientific American(八)月

A cluster of villages in China's Guizhou province has been plagued by an outbreak of disease that damages teeth and bones. Now, a new study by Chinese and American researchers puts the blame on polluted coal burned in home fireplaces. In small quanti

发表于:2019-01-14 / 阅读(104) / 评论(0) 分类 VOA标准英语2010年(十)月

Ah yes.The ol' fluoride rinse at the dentist. Not pleasant. But hey, good for your teeth, right? 没错,这是牙医洗牙用的含氟漱口水。确实够闹心的。但毕竟对你的牙齿有益不是吗? Well now materials scientists have been

发表于:2019-01-20 / 阅读(92) / 评论(0) 分类 2018年科学美国人1月

NEW YORK Plug in your car, then unplug, and drive away. More and more consumers are doing just that. At the 2014 New York Auto Show many automakers unveiled electric or hybrid vehicle to address the growing global appetite for environment-friendly ca

发表于:2019-01-30 / 阅读(97) / 评论(0) 分类 英语新闻

AGRICULTURE REPORT – March 12, 2002: Carbon Dioxide and Crops By George Grow This is the VOA Special English AGRICULTURE REPORT. Increasing levels of carbon dioxide gas in Earth’s atmosphere have

发表于:2019-01-30 / 阅读(122) / 评论(0) 分类 农业与发展

SCIENCE IN THE NEWS - November 26, 2002: Dental Health By Nancy Steinbach VOICE ONE: This is Steve Ember. VOICE TWO: And this is Bob Doughty with Science in the News, a VOA Special English program abo

发表于:2019-01-30 / 阅读(105) / 评论(0) 分类 科技之光

今天我们要学的词是 fluoride. Fluoride 氟化物。The U.S. government is lowering the recommended amount of fluoride added to drinking water for the first time in more than 50 years. 美国政府50多年来首次降低饮用水建议添加的氟

发表于:2019-02-02 / 阅读(99) / 评论(0) 分类 英语单词荟萃

SEOUL/WASHINGTONThe U.N. Security Council said Wednesday that it was working to craft new sanctions against North Korea after its latest nuclear test, while the United States and other world powers voiced skepticism about Pyongyang's claim that the u

发表于:2019-02-04 / 阅读(57) / 评论(0) 分类 英语新闻

Questions 12-20 The elements other than hydrogen and helium exist In such small quantities that it is accurate to say that the universe somewhat more than 25 percent helium by weight and somewhat less than 25 percent hydrogen. Astronomers have measur

发表于:2019-02-05 / 阅读(120) / 评论(0) 分类 托福英语

PREFIX 1.a-:of;on;intensive;negative,not,without;ad-;ab-. 2.ab-:away from,off. 3. ad-:to;at;for. 4. aer(o)- :relating to air . 5.al-:all. 6.ambi-:on both sides,around. 7.amphi-:on both sides,around. 8.an-:negative,not,without. 9.ana-:upon,up,on. 10.a

发表于:2019-02-06 / 阅读(136) / 评论(0) 分类 雅思英语

December 30, 1954 I am speaking not as a Briton, not as a European, not as a member of a western democracy, but as a human being, a member of the species Man, whose continued existence is in doubt. The world is full of conflicts: Jews and Arabs; Indi

发表于:2019-02-09 / 阅读(140) / 评论(0) 分类 英语美文

9月16日是墨西哥馆日,墨西哥馆五颜六色的风筝森林吸引了不少人的眼球,你知道小小的风筝里有什么大学问吗?其实风筝也有很多种分类哦,一起来看看吧。 说到kite这个单词,这也许是我们

发表于:2019-02-18 / 阅读(145) / 评论(0) 分类 英语口语

North Korea conducted a 'successful' hydrogen bomb test, Pyongyang has confirmed. The thermonuclear weapon triggered a massive 5.1 magnitude earthquake when it exploded at 10am local time on Wednesday. 平壤方面已经证实,朝鲜成功的进行了

发表于:2019-02-18 / 阅读(79) / 评论(0) 分类 英语新闻
学英语单词
acosmeryx castanea
acridioxanthin
alopecuroides
anoestrus
backdoors
bi-unique
Boynton Beach
British Colony
bulk station
burstiness
canaliculi caroticotympanici
choking winding
chromogen green
circle scanner
circular-pitch
combined linear system
constant-mean
continuous span
cylindrical lapping
decorrelation time
dendrobranchiates
derestricts
economic criteria
employment
escalon
external toothing
fake-process color
family of deformations
ferrite magnetostrictive vibrator
flock and rag dyeing plant
foramadinocillin
ganglionnodosum
gradation in size
Gredos, Sa.de
heavy medium separation
historical data device
hurtlings
hydraulic dynamometor
imbibitions
indirect wave
interstitial fluid colloid osmotic pressure
Jodairol
John Cage
Lakists
lentula
lexical hierarchy
liquid bomb
lising
Machead
magnetic conveyer
mean profile
metasedimentary rock
muscular plugging
Mydriacyl
myxo-enchondroma
NAVBIOLAB
nda
noncrystalline solid
nonlaundry
one another
optomyometer
order condition for identification
ormondroyds
parallel and decentralized manner
parietal block block
parvifagarine
passivation potential
peristalsis
personalises
pische
programed logic
radiation source substrate
radio channel jammer
range oneself
rated instrument limit primary current
ratio of slenderness
redundancy encoding
reference divider
related transaction
relative dormant period
roller jaw
run of press
saliotite
shrink back from
single-particle orbit
sodium oxacilin
stand out from the crowd
takes a note of
ternary polymerization
Teufen
that's it in a nutshell
three-layer structure
two-way vioce-frequency transmission path
udvardy
unmuscular
vcd
velvetbreasts
virtualstation
yellow peach
zero real growth budget
zero-guy
zetta-grams