吸声系数,声吸收率

When Pablo Panda Sandoval made history with 3 home runs in game one of the world series his head was probably buzzing. But when batters in chilly Detroit had the ball not quite right in the next couple of the nets, it will be their hands that buzzing

发表于:2018-12-24 / 阅读(183) / 评论(0) 分类 Scientific American(十)月

This is Scientific American's 60-second Science. I'm Steve Mirsky. Got a minute? Can you name those notes? Probably not. Perhaps one in ten thousand speakers of European languages has perfect pitch - the ability to recognize a note without having hea

发表于:2018-12-24 / 阅读(218) / 评论(0) 分类 Scientific American(五)月

This is Scientific American's 60-second Science. I'm Karen Hopkin. If you ever got picked on in the schoolyard, you might have wished for some sort of superpower, like unbeatable speed or maybe just the ability to completely disappear. Now scientists

发表于:2018-12-24 / 阅读(203) / 评论(0) 分类 Scientific American(五)月

Scientists analyzed around 2,500 of those calls, and found that the second part (sound) is nearly identical in pitch every time from each whale: 16 hertz, or four octaves below middle C. And the slight variations in frequency that do exist are only a

发表于:2019-01-02 / 阅读(213) / 评论(0) 分类 60秒科学

Hybrid cars are good for the environment. But scientists say that they might be bad for pedestrians. Because hybrids are so quiet, it can be hard for walkers to hear them until its too late. Listen to this. [quiet car sound] Thats a Toyota Prius mov

发表于:2019-01-02 / 阅读(241) / 评论(0) 分类 60秒科学

Can you name those notes? Probably notperhaps one in 10,000 speakers of European languages has perfect pitch, the ability to recognize a note without having heard any reference note first. But theres a much better chance you could successfully name

发表于:2019-01-02 / 阅读(236) / 评论(0) 分类 60秒科学

If you ever got picked on in the schoolyard, you might have wished for some sort of superpower: like unbeatable speed or maybe just the ability to completely disappear. Now scientists at the College of Wooster in Ohio say that you might have had a s

发表于:2019-01-02 / 阅读(276) / 评论(0) 分类 60秒科学

This is Scientific American's 60-Second Science. I'm Karen Hopkin. This will just take a minute. Every year, scores of manatees are killed by boats in Floridas waters. Their plight is an ecological concern. And everyone from marine biologists to Marg

发表于:2019-01-08 / 阅读(218) / 评论(0) 分类 Scientific American(十一)月

This is Scientific American's 60-second Science. I'm Karen Hopkin. This will just take a minute. Hybrid cars are good for the environment, but scientists say that they might be bad for pedestrians. Because hybrids are so quiet that can be hard for wa

发表于:2019-01-08 / 阅读(207) / 评论(0) 分类 Scientific American(五)月

We humans are pretty good at communicating with sounds other than words. But how much of this is hard-wired, and how much do we pick up from others? To find out, researchers recorded the nonverbal sounds of people born deaf, as they responded to a ra

发表于:2019-01-08 / 阅读(282) / 评论(0) 分类 Scientific American(十一)月

Blue whales off the California coast make calls that, sped up 10 times, sound like (sound of two-part call). The original is a wall-rattling frequency too low for us to hear. Scientists analyzed around 2,500 of those calls, and found that the second

发表于:2019-01-08 / 阅读(193) / 评论(0) 分类 Scientific American(八)月

Country Music Ladies Put Men in Their Place American country music lyrics often describe women as they might appear in mens dreams. This is especially true of songs by many male artists. But the songs by Maddie Marlow and Tae Dye are different. The t

发表于:2019-01-12 / 阅读(220) / 评论(0) 分类 2015年VOA慢速英语(九)月

Boston Symphony Makes Music in Mountains When Serge Koussevitzy, the Russian-born conductor of the Boston Symphony Orchestra, opened Tanglewood in 1937, he chose an all-Beethoven program, including the Pastorale Symphony. When conductor Christoph von

发表于:2019-01-13 / 阅读(176) / 评论(0) 分类 VOA标准英语2012年(七月)

By Alisha Ryu Nairobi 18 November 2009 A U.S.-flagged container ship which was hijacked by Somali pirates seven months ago has been attacked again off the coast of Somalia. Pirates were unsuccessful in their second attempt to hijack the Maersk Alaba

发表于:2019-01-14 / 阅读(219) / 评论(0) 分类 VOA标准英语2009年(十一月)

The Tiangong-2 space lab, though adopting the structure of Tiangong-1 without too many changes in appearance, has been designed to function much stronger than its predecessor. Zhu Congpeng, chief designer of the lab, says they've focused on a variety

发表于:2019-01-19 / 阅读(213) / 评论(0) 分类 2016CRI中国国际广播电台

通知与确认 Acknowledgments Confirmations 通知对方接到来信Acknowledging receipt of letters1. Dear Mr/Ms,Thank you for your letter No. A-3 of 6th May, offeringus 6 UI-4 Viewdatas. We have passed it on to ourTechnical Department for their c

发表于:2019-02-06 / 阅读(243) / 评论(0) 分类 实用英语
学英语单词
-som
a little knowledge is a dangerous thing
active aurora
admitting
advertation
advertising space
air-cored betatron
angular calibration constants
Arteria plantaris profundas
basal keel
baser
better same order bias estimator
bidirectional translocation
boarding-card
border-brim
Bromodifluoroethane
category method
charge-weight ratio
chief sperm
chow hound
Claude Elwood Shannon
closed escort
cocartesian square
code manager
community of assets
computing estimated tax
conjugate filter
corporate takeover
Dalitz pair
Dendrobium clavatum
diffuse threshold decoder
DR (data receiver)
dynamic allotropy
EP (end of program)
fall out of favor
faulty design
FCAF
ferromagnetic oxide parts
fluidness
foreclosure property
frustrated total reflection filter
function generation technique
gnaphalium involucratum simplex
good growing weather
grid-work
hail-fellow
haloeremion
heavy lift system
humblete
hyperpn(o)ea
hypocalcemic
illaqueation
immersionism
inboarding
intelligent fuzzy network
internal shipment
Landmann's tyberculin
leucotaxin
loopfuls
Lysimachia perfoliata
macrofiction
main crosscut
market breadth
merchandise note
metabolas
Mikadoism
ms-doss
national economic stability
Newquay Bay
niperyt
non-directional navigation beacon system
nuclear fusion reacotr
off.the
oils of vitriol
okene
optically thin medium
overclads
parabenzene
pavot
renove
residual swelling
roperia tesselata
rosa chinenses
Satsuma-hantō
shading-pole type relay
spark-gap adjustment
spondyloarthropathy
super thermostatic oil bath
synedrion
syntactic semantics
tengerite-(Y)
thermoelectric power coefficient
turfage
twin-hearth furnace
typhoon damage
umbelick
uncentered biaxial interference figure
vapor compressing distillation plant
Veronica arvensis
vertical escape exit
W3
wiredrew