极坐标系

by Jason Marshall Theres been a lot of talk about 2D versus 3D in the television and movie industries lately. But what exactly does one, two, and three-dimensionality really meanboth in the everyday world and in math? Well, prepare to have your curio

发表于:2018-12-07 / 阅读(188) / 评论(0) 分类 数学英语

A new study has found that the Arctic's iconic polar bears are finding it harder to hunt for food due to melting sea ice caused by climate change, putting the species at a growing risk of extinction. Researchers from the United States Geological Surv

发表于:2018-12-24 / 阅读(213) / 评论(0) 分类 2018CRI中国国际广播电台

When the Arctic Ocean freezes over in the autumn, polar bears set off in search of their favorite meals: fatty ringed seals and bearded seals. By the summer, the sea ice begins to melt and break apart. Deprived of access to the tasty seals, polar bea

发表于:2018-12-24 / 阅读(209) / 评论(0) 分类 2016年Scientific American(十)月

Climate Change Fires Up Polar Bear Treadmill 气候变化害苦了北极熊 Polar Bears spend most of their time roaming the sea ice in search of seals. And seals spend most of their time underneath that ice, avoiding the top predator. But climate ch

发表于:2018-12-24 / 阅读(256) / 评论(0) 分类 2017年Scientific American(八)月

Seventy-nine degrees north latitude is near the top, at the cold edge of the world. In the winter, when temperatures plunge below freezing, there is complete darkness at noon. During summer, the sun shines at midnight, there is no place to hide. Dang

发表于:2018-12-30 / 阅读(347) / 评论(0) 分类 国家地理2007年

She worries a lot. She worries about polar bears. They are big, white bears. They live in the north. They need snow. They need ice. They need cold weather. There is too much pollution. Pollution heats up the Earth. Heat melts the ice. The ice is the

发表于:2018-12-31 / 阅读(293) / 评论(0) 分类 儿童英语小故事

By Paul Sisco Washington 16 May 2008 The United States Government, Wednesday [May 14] officially added polar bears to the list of threatened animals under the Endangered Species Act. Bush administration scientists decided the species is at risk of be

发表于:2019-01-13 / 阅读(167) / 评论(0) 分类 VOA标准英语2008年(五月)

New Movie Boosts Campaign to Save Polar Bears Polar bears are in trouble. Scientists say only 20,000 remain, and their long term survival could be at risk. The new IMAX movie, To the Arctic, is narrated by actress Meryl Streep. The movie tells the st

发表于:2019-01-13 / 阅读(210) / 评论(0) 分类 VOA标准英语2012年(五月)

New Texas Institute Coordinates Space Medicine Research Since the human space flight adventure began more than 50 years ago, scientists have learned a lot about things like the effects of weightlessness on bones and muscles, and the danger of increas

发表于:2019-01-13 / 阅读(240) / 评论(0) 分类 VOA标准英语2012年(四月)

Polar Scientist Charts Melting Caused by Climate Change Michael Gooseff follows water to the end of the earth. The Pennsylvania State University hydrologist works in remote regions of the Arctic and Antarctic, where ice and frozen ground are thawing.

发表于:2019-01-14 / 阅读(153) / 评论(0) 分类 VOA标准英语2011年(八月)

BBC Learning English Weekender Polar Explorer Amber: Hello, I'm Amber, and youre listening to bbclearningenglish.com. In Weekender today, we listen to an interview with explorer, Rosie Stancer. In March, Rosie sets off on her latest expedition walki

发表于:2019-01-16 / 阅读(250) / 评论(0) 分类 Weekender

STOCKHOLM, May 8 (Xinhua) -- The 2012 Swedish Polar Music Prize was awarded to the American singer-songwriter Paul Simon and the Chinese American cellist Yo-Yo Ma, the prize committee said in a statement on Tuesday. For five decades, Paul Simon has b

发表于:2019-02-09 / 阅读(229) / 评论(0) 分类 英语新闻

Voice 1 Thank you for joining us for todays Spotlight. Im Rebekah Schipper. Voice 2 And Im Joshua Leo. Spotlight uses a special English method of broadcasting. It is easier for people to understand, no matter where in the world they live. Voice 1 Sib

发表于:2019-02-14 / 阅读(184) / 评论(0) 分类 环球英语 Spotlight

The dogsled skimmed silently over the frozentundra. The seal hunter ran alongside it. Sometimeshe cracked his whip against the ice. The snowdrifts looked like giant white sculptures asthe sun slipped behind the frozen hills. Then a fullorange moon ro

发表于:2019-02-17 / 阅读(189) / 评论(0) 分类 汪培珽儿童英文分级书单《神奇树屋》

The dogs were barking wildly at two smallcreatures playing in the moonlight. Polar bear babies! cried Annie. One roly-poly cub leaped onto the other. Then theyboth rolled through the snow. Hi, little bears! Annie called. The cubs jumped up and shook

发表于:2019-02-17 / 阅读(176) / 评论(0) 分类 汪培珽儿童英文分级书单《神奇树屋》

The cubs whimpered louder. They want to go to her, but they're afraid of theice, whispered Jack. Annie petted the cubs. Don't be afraid, she told them. You'll get back toyour mother.The big polar bear growled. She paced back andforth, sniffing the ai

发表于:2019-02-17 / 阅读(164) / 评论(0) 分类 汪培珽儿童英文分级书单《神奇树屋》

Jack, you can get up now, said Annie. Jack opened his eyes. Annie was standing over him. She still had her mask on. We're on safe ground, she said. Jack felt as if he'd been dreaming. He lookedaround. They had reached the tundra at the edge ofthe fro

发表于:2019-02-17 / 阅读(190) / 评论(0) 分类 汪培珽儿童英文分级书单《神奇树屋》

Now only the moon shone on the snow. Jack looked around for the polar bear. She was gone. Where'd she go? asked Annie. I don't know, said Jack. He looked over thetundra. There was no sign of the giant bear or hercubs. Maybe she's not interested in sc

发表于:2019-02-17 / 阅读(185) / 评论(0) 分类 汪培珽儿童英文分级书单《神奇树屋》

BEIJING, June 21 (Xinhua) -- China will launch a new icebreaker for use during an upcoming 2013 polar expedition, a senior oceanic official said on Tuesday. Both the new icebreaker and Xuelong (Snow Dragon), an icebreaker that operated in Antarctica,

发表于:2019-02-18 / 阅读(240) / 评论(0) 分类 英语新闻

Voice 1 Hello, Im Marina Santee. Voice 2 And Im Ruby Jones. Welcome to Spotlight. This programme uses a special English method of broadcasting. It is easier for people to understand, no matter where in the world they live. Voice 1 A tall man stands s

发表于:2019-02-21 / 阅读(215) / 评论(0) 分类 环球英语 Spotlight
学英语单词
a spent force
advanced-level
affective dementia
alarm burglar
Alfred Tennyson
Arbitration Appraisal
ball-thrombus
ballasting device
bartolomeu
baym
bellowstype
benzyl salicylate
big shows
big-eared bats
borough-town
Bükkzsérc
cholecysts
clandinin
coarsegold
conical refining engine
conjunctival secretion
create from raw material
cyclic file
detachable bulkhead
dolph-chebyshev weighting
draw plough
EBIC
element of credit
embitterment
epigenetic mineral
excretory tube
extramuscular
extrinsicate
fictiveness
first order integral-differential equation
flight/navigation instruments
fracture toughness property
Gallium-67
Gambier, C.
geise
good agricultural practice
gudgeon bolt
horaga albimacula triumphalis
horizon transmission
house of sunshine
improvement factor
in bonis habere
Indian robin
indication magnet
International Association of Geodesy
intersensorial
irene curie
Kaldo converter
keep one's own advice
Kyzylkum Desert
lobe receptacle
magmani
materials reradiate
melting stage
metar
Mildred L.
missiness
mortise and tenon joint milling cutter
multi expansion
non-modifiable
Novell Authorized Education Center
num-lock key
O.B.E.
Odissi
offsprings
over-severe
palolos
pertusaria tetrathalamia
phonaesthemic
polycyclic aromatic hydrocarbon
power to promulgate law
power-driven vehicle
pulse width coding
rear gate side post
regrounds
rellies
rembrandthuiss
reobserve
ring-bone
roll sleeve joint
saisies
self programmed electronic equation delineator
sit on something
spek-
steam coals
stevely
stink bomb
swerver
tetraskele
thalictricavine
threephase short-circuit
tingitamine
veals
wcb
weaver's warp
work performance
yoshigi