音标:[aisəu'ɔlifain] ;
n. 异烯烃;异构烯烃,异烯

A hundred years ago, there are one and a half billion people on earth. Now, over six billion crowd our fragile planet. But even so, there are still places barely touched by humanity. This series will take you to the last wildernesses and show you the

发表于:2018-12-03 / 阅读(133) / 评论(0) 分类 探索与发现2012年

The UN refugee agency says it is worried about the security of people living in isolated villages near the former conflict zones of Georgia. It says some 2,300 people from villages in the buffer zone between the Georgian town of Gori and the breakaw

发表于:2018-12-16 / 阅读(180) / 评论(0) 分类 VOA标准英语2008年(八月)

The penguins stay when all other creatures have fled because each guards a treasurea single egg rested on the top of its feet and kept warm beneath the downy bulge of its stomach. There is no food and no water for them. And they will not see the sun

发表于:2018-12-27 / 阅读(137) / 评论(0) 分类 探索与发现2012年

By Carol Pearson Washington, DC 29 May 2006 watch Autism Gene report Researchers at the University of Texas Southwestern have been able to genetically change mice so their behavior is similar to some people with autism. The researchers hope their di

发表于:2019-01-13 / 阅读(219) / 评论(0) 分类 2006年VOA标准英语(五月)

RACHEL MARTIN, HOST: There was a gathering here in Washington, D.C. last week that had nothing to do with the inauguration or with politics. It was an occasion for matchmaking, although not a romantic kind. Here, farmers got set up with chefs in an e

发表于:2019-01-16 / 阅读(197) / 评论(0) 分类 2017年NPR美国国家公共电台1月

They are constantly on the move. New-born calves have to be up and running the day they are born. But the vast herds do not travel alone. Wolves. Packs of them, eight to ten strong, shadow the migration. And they are hungry. Its the newly born calves

发表于:2019-01-23 / 阅读(157) / 评论(0) 分类 探索与发现2012年

But they are hungry and eager to reach their mother whos delayed feeding them on this special day. Now she lures them with the promise of milk, the only food the cubs have known since they were born, deaf and blind beneath the snow some two months ag

发表于:2019-01-23 / 阅读(156) / 评论(0) 分类 探索与发现2012年

Day 10. And the mother has let her cubs a mile from the den. Its time to put them to the test. Theyve grown enormously in confidence, but they dont have their mothers sense of urgency. At last it seems that they are ready for their journey. And they

发表于:2019-01-23 / 阅读(139) / 评论(0) 分类 探索与发现2012年

Midsummer on the tundra and the sun does not set. At these altitudes, the suns rays are glancing and not enough of their energy reaches the ground to enable trees to grow. Youll need to travel five hundred miles south from here before that is possibl

发表于:2019-01-23 / 阅读(135) / 评论(0) 分类 探索与发现2012年

As we travel south, so the suns influence grows stronger. And at 50 degrees of latitude, a radical transformation begins. Summers here are long enough for broadleaf trees to replace conifers. Broadleaves are easier to eat and digest, so now animals c

发表于:2019-01-23 / 阅读(154) / 评论(0) 分类 探索与发现2012年

The advance of the seasons brings constant change. As the suns influence diminishes in the north, so the deciduous forests of America begin to shut down, losing their leaves in preparation for the dark, cold months ahead. One season hands over to ano

发表于:2019-01-23 / 阅读(142) / 评论(0) 分类 探索与发现2012年

The character of the forest changes as we descend, becoming ever darker and damper, favoring different kinds of animals and plants. Less than two percent of the sunlight reaches the floor. But even here there is extraordinary variety. In the Great Is

发表于:2019-01-23 / 阅读(130) / 评论(0) 分类 探索与发现2012年

The strike of a great white shark lasts a mere second. Slowing it down forty times reveals the technique and immense strength of this massive predator. If surprise fails, there will be a chase. The shark is faster on a straight course, but it cant tu

发表于:2019-01-23 / 阅读(250) / 评论(0) 分类 探索与发现2012年

The sun beating down on tropical waters powers the weather systems of the globe. Moisture evaporates from the warming ocean and rises to create great storms. The winds generated out at sea sweep inland across the continents. As they travel across the

发表于:2019-01-23 / 阅读(147) / 评论(0) 分类 探索与发现2012年

Deer are frequent casulties of the harsh winter. And these leopards are not above scavenging from a corpse. African leopards could never survive here. But the Russian cats have thick fur to shied them from the cold. There are only 40 Amur leopards le

发表于:2019-01-23 / 阅读(167) / 评论(0) 分类 探索与发现2012年

Their secret is teamwork. Impala are their favourite prey. They start to hunt and the pack splits up. An aerial viewpoint gives a new insight into their strategy. As the dogs approach their prey, they peel off to take up separate positions around the

发表于:2019-01-23 / 阅读(141) / 评论(0) 分类 探索与发现2012年

The dogs know their prey must come out or drown. Now its a waiting game. The rest of the pack are calling. Theyve made a kill in the forest and this is an invitation to join in the meal. The impala is in luck. A pack this size kills once a day and ev

发表于:2019-01-23 / 阅读(148) / 评论(0) 分类 探索与发现2012年

All across southern Africa, all animals are journeying for the same reason. Buffalo join the great track. Nowhere else on Earth are so many animals on the move for the same urgent purpose. They are all heading for the swamps of the Okavango, a vast i

发表于:2019-01-23 / 阅读(159) / 评论(0) 分类 探索与发现2012年

At the peak of the dry season in the Kalahari, water arrives in the Okavango. It fell as rain a thousand miles away in the highlands of Angola and has taken nearly five months to reach here. The water drives out insects from the parched ground which

发表于:2019-01-23 / 阅读(131) / 评论(0) 分类 探索与发现2012年

By Melinda Smith Baltimore, Maryland 05 September 2006 watch report Celiac Disease For thousands of years, human beings have suffered from a genetic disorder that has received attention only in the last few decades. The disorder is called celiac dis

发表于:2019-01-26 / 阅读(276) / 评论(0) 分类 2006年VOA标准英语(九月)
学英语单词
aggregate cooling
air ventilator
alkyl mercuric chloride
Allium eusperma
Bar Cochba
bean-flickers
biological hazard potential
bistre
bromohyperhirdrosis
cheiropodaligia
chrysanthemum multicaule desf.
Code of Dangerous Goods
colour forme
concentration of river network
Dahlak
Didymocarpus sinoprimulinus
directional quantization
driven snow
earth reflection
easing gear
electron device
emulsion sintering method of spinning
Eriolaena glabrescens
eriometer
esophageal pressure sensor
European-style option
evirating
Fluvin
freezing machine
fringed filter
fuzzy switching function
gerades
get too big for one's breeches
grade of timber
hand interrupter
hypoadlbuminemia
Irkunii
isophthaloyl
Java platform
jokanaans
kicking arse
Ladies' Aid (Society)
Leifsons flagella staining
ligamentous injury of knee joint
light-blues
Liskantin
lorentzian gas
loutherbourg
lubbe
lucens
lusb
malice in law
maximum rate of back pressure
midian
Millennium Bridge
misdesign
moderationism
necydalis mizunumai
Newtonian shear viscosity
nondiscerning
office boy
Open System Interconnection Reference Model
operational standard cost
orthant probabilities
overwatcher
pancreath-
passeboard
Perranporth
pressure on foundation
primary cell wall
razgrads
relamping
relative spacing
remote reading tachometer
Rivamonte
seawant
selvedge hem
sending key
set right
set-reset i/o parameter
shape-shiftings
six score
smolderers
snakemeat
sound proof door
Stevenson, Robert Louis
the kiss of death
Totness
transmigrable
transplantable tumor
trial ship
trioxygenated
tropicamide
two aqueous phase extraction
uprima
voting trust certificate
watering pots
well-dried
well-tanned
world environment
wyry