2-4-二苯基恶唑衍生物

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(70) / 评论(0) 分类 探索与发现2012年

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(71) / 评论(0) 分类 探索与发现2012年

An ass and an ox,fastened to the same yoke,were draging a waggon.While the ox was pulling with all his might he he broke a horn.The ass swore that he had got no help whatever from his weak companion.Exerting himself in the labour,the ox b

发表于:2019-01-09 / 阅读(149) / 评论(0) 分类 趣味英语

Azaz Residents Pick Up After Aerial Bombings The residents of Azaz clean up and mourn after Wednesday's deadly bombing by Syrian government warplanes. Azaz had been peaceful in recent months, although forces of the rebel Free Syrian Army have had to

发表于:2019-01-13 / 阅读(103) / 评论(0) 分类 VOA标准英语2012年(八月)

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(77) / 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(84) / 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(72) / 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(75) / 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(91) / 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(66) / 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(64) / 评论(0) 分类 探索与发现2012年

The female retires to consider her verdict. Its hard not to feel deflated when even your best isnt good enough. The sun influences the lives in the ocean just as it does on land. Its richest parts are those where waves and currents bring fertilizing

发表于:2019-01-23 / 阅读(98) / 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(182) / 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(64) / 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(97) / 评论(0) 分类 探索与发现2012年

This is in Africa rarely seen, a lush water world. Some creatures are completely at home here. These are lechwe, antelope with hooves that splay widely enabling them to move at speed through the water. For others, the change is far less welcome. Babo

发表于:2019-01-23 / 阅读(50) / 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(60) / 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(66) / 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(73) / 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(60) / 评论(0) 分类 探索与发现2012年
学英语单词
aculus albopurpurascus
administrative precedent
akses
angle beam contact unit
apparant focus
as-cast finish
Asterias Seamount
autotellers
Bacillus coli similis
baseless rumor
battery of coke-oven
beam with both ends built-in
bulimy
canonical form of a linear hypothesis
canonically bounded
cephus
comminuted fracture of head of humerus
compensated scale barometer
correlated random variables
defective interfering particle
Des Plaines
digital channel
discipline-based
drain flash tank
durity
edging station
exoculate
fat-tailed sheep
fattypuff
formal tea
formaldehyde odour
haori
haploidentical donor
hard-to-burn-refuse
health promoting school
hierarchy objective
Hydraulic Tools
hydrothermal
hydroxylamine-o-sulfonic acid
individual lead
insurance for the transportation of imported and exported goods
isoepitaxial growth
Lawen-Roth syndrome
light condition
lighter-than-air aircraft
local transport
ludibry
Mahamaya
memory board
methandienone
method for capillary blood pressure
methyl hespreidin
micrococcus paludosa
microcontacts
multigroup neutron diffusion equation
myocardin
non-quoted
norerythrosuamine
nutritional edema syndrome
ocosingo
page address
palaeo astrobiology
pampuro
passive adaption
per diem
perchess
pomodoro
PPHK
precision analysis
prescribed supervision
printer's devil
rate of treatment of passenger's comment
Riemann(ian) manifold
ring mouse
roughing pass
SDH
seafarers education service
sen changer
Shangani R.
simultaneous assignment
sowme
sphenotics
street-sign
strongmindedness
surface-piercing foil
synthetic energetics
take a roundabout course
Tarkovsky
tofo
trans-condyloid
turbine driven auxiliary unit
turbulent dissipation
uranium silicide
Uwet
Volhynia
well-cared-for
work angle
wu hua t?ng
yenning
zelinski
Zinnia multiflora
zonal profile