强力场

Broadcast: Apr 04, 2003 Iraqi President Saddam Hussein appeared on state television Friday, calling on Iraqis to be strong to defeat coalition forces. Mr. Hussein 's speech came a short while after an

发表于:2019-01-03 / 阅读(90) / 评论(0) 分类 VOA2003(上)-国际时讯

By Cindy Saine Washington 04 October 2007 The U.S. Congressional Human Rights Caucus held a hearing Thursday on the joint African Union-United Nations peacekeeping force to be deployed to Sudan's Darfur region. Several members of Congress and a numbe

发表于:2019-01-16 / 阅读(86) / 评论(0) 分类 2007年VOA常速英语(十月)

Radiation causes damage at the most fundamental level. It mutates the blueprint of life, DNA. Earth's magnetosphere is our crucial defense. It's so fundamental to our evolution and continued existence that the race is on to understand why it's changi

发表于:2019-01-22 / 阅读(72) / 评论(0) 分类 自然百科2011年

Earth's magnetic field has reversed thousands of times since its formation 4.5 billion years ago. And scientists now believe that the next reversal is imminent. The race is on to predicting exactly when it will occur. In 2010, the European Space Agen

发表于:2019-01-22 / 阅读(55) / 评论(0) 分类 自然百科2011年

As the reversal approaches, the decay of our magnetic field will continue and cosmic radiation will get increasingly close to the Earth's surface. As the reversal approaches, the decay of our magnetic field will continue and cosmic radiation will get

发表于:2019-01-22 / 阅读(77) / 评论(0) 分类 自然百科2011年

During its magnetic cycle, the Sun undergoes periodic changes in activity. Every 11 years, it enters solar maximum. This 11 years cycle of solar activity has peaks where theres lots of solar storms. And right now where the sun is taking a little napp

发表于:2019-01-22 / 阅读(115) / 评论(0) 分类 自然百科2011年

Six years later, they come to believe these light flashes are the results of high energy, heavy cosmic rays penetrating the spacecraft and the crew members' eyes. These/ protons or electrons, just very, very high energy, ripped / part of atoms, sprin

发表于:2019-01-22 / 阅读(88) / 评论(0) 分类 自然百科2011年

Glatsmire's model shows that the magnetic poles swap places spontaneously due to / complex processes within the core. We were used to the idea that a compass points somewhere near the North Pole and hence we can use it for navigation, but there are p

发表于:2019-01-22 / 阅读(75) / 评论(0) 分类 自然百科2011年

By analyzing thousands of lava samples, geophysicists discover/ that the Earth's magnetic field has reversed over 18,000 times in the last 20 million years. On either side of these reversals is a long period of dramatically reduced field strength. Du

发表于:2019-01-22 / 阅读(72) / 评论(0) 分类 自然百科2011年

We drive them about 20 miles away to the North, and release them, and we track them as they try to fly back home. We drive them about 20 miles away to the North, and release them, and we track them as they try to fly back home. Hes up, OK. Holland wa

发表于:2019-01-22 / 阅读(84) / 评论(0) 分类 自然百科2011年

By analyzing different samples of lava, Herrero / Bervera has built up a picture of how the filed has changed since long before humans were around. They are actually the recorders of the Earth's magnetic field in hundreds of years, thousands of years

发表于:2019-01-22 / 阅读(83) / 评论(0) 分类 自然百科2011年

If we could flip a switch and just turn off the Earth's magnetic field, it will take about 15,000 years to disappear, based on the rate of decay of the field that we've seen over the last 150 years. It's currently decaying at a rate that would see an

发表于:2019-01-22 / 阅读(76) / 评论(0) 分类 自然百科2011年

In polar regions where the magnetic field is / weakest, auroras glow in the sky. These dazzling displays of colored lights form when solar particles slam into gases in our atmosphere causing them to glow. The stronger the solar wind, the more dramati

发表于:2019-01-22 / 阅读(87) / 评论(0) 分类 自然百科2011年

Scientists believe that the South Atlantic Anomaly, is a sign of a global decline in the magnetic field. Evidence of this comes from a surprising source. Dr. Mimi Hill uses pottery to uncover the secrets of earth's magnetic past. Ancient pots tell us

发表于:2019-01-22 / 阅读(82) / 评论(0) 分类 自然百科2011年

It's clear from the fact that the Martian crust is strongly magnetized, that there must have been a magnetic field on Mars in the past, that the only way we know to magnetize rocks is for them to form in the presence of magnetic field. Why did Mars l

发表于:2019-01-22 / 阅读(75) / 评论(0) 分类 自然百科2011年

The loss of the magnetic field has a catastrophic impact on the planet's evolution. Mars becomes the red planet we see today. If earths magnetic protection continues to fade, would it suffer the same fate? If it vanishes completely, the planet might

发表于:2019-01-22 / 阅读(92) / 评论(0) 分类 自然百科2011年

Easily confused by this idea, there has a big thawed iron inner core, so that I think it's just the bar magnet, just permanent magnet frozen in nad, and that's where causes all the magnetic field. But it's too hot inside the Earth, that can't happen

发表于:2019-01-22 / 阅读(82) / 评论(0) 分类 自然百科2011年

As the vast sphere reaches / maximum speed, something incredible happens. Huge lines of magnetism arc in and out of the model core. Well, we can't see the magnetic field coming out of the experiment, we can measure them, we can put many different mag

发表于:2019-01-22 / 阅读(83) / 评论(0) 分类 自然百科2011年

Larry Newitt from the Geological Survey of Canada charts the movement of the magnetic North Pole as it wanders the icy reaches of northern Canada. To determine where the magnetic pole / is, we can't rely on one single observation. What I try to do is

发表于:2019-01-22 / 阅读(86) / 评论(0) 分类 自然百科2011年

Blockson's computer model reveals that at the South Atlantic Anomaly, the magnetic field isn't just weaker than anywhere else on the planet. It's actually reversed polarity. There is a patch on the core in the South Atlantic where things are not poin

发表于:2019-01-22 / 阅读(86) / 评论(0) 分类 自然百科2011年
学英语单词
.art
acoustic theory
adad
algebraic norm
Allemande Left
approximation of laws
ardouous
asymmetric karyotype(stebbins1950)
Atka mackerel
balloon former
Bang test
bar primary
bayesian inference network
be at someone
best bowers
bimetallic plate
Bobrovo-Dvorskoye
bridge failure
bronchotomies
budgetary control report
cairnie
chromic chloropentammine dichloride
cramr
crumbler
curve of field distribution
dendrocytes
digital voltage code
dippy
directing control to background job
e. h. harrimen
embryo fisheries
enamel layer
energy agriculture
error burst
evaporation to dryness
full-powers
gas force open type
Gibberella saubinetii toxins
going-over
gris-
Grönskåra
hemaocnia
hexalite
HFT (hot functional test)
Hjarbæk
hohlweck
insect-flower syndrome
isoagglutinin
jankowiak
jejunocolostomies
kid-gloves policy
lawn chair
letin
Limaciopsis
linen yarn
lochioschesis
make a man out of
malach
maximum grinding depth
medial crural cutaneous branches
metravigor
milhem
mravinsky
Muskovie
mvmt
naturally occurring radionuclide
nineteenpence
Nodi lymphatici vesicales laterales
non defense expenditure
offshore swap
OLH
oropharynges
P-anisidine value
Paurometabala
phacelia tanacaete-folia benth.
plexus venosus seminalis
polymacon
present sth at
promotion money
Pseudovincaleukoblastinediol
purples
QARNNS
reblocked
reducing twin elbow
relocation package
salmonburger
screen format
secule
slow-decline
software test
strain gauge scanner recorder
superinsulators
Tarini's fascia
tax-gatherers
threatened abortion
Tokko
Trichlorisobutylicus
typhlostomy
universalis
unredressed
valerolactone
wet damage accident