(valence 的过去时) n. 原子价
[化] 化合价; 原子价
past tense of valence
n. (biology) a relative capacity to unite or react or interact as with antigens or a biological substrate
n. (chemistry) a property of atoms or radicals; their combining power given in terms of the number of hydrogen atoms (or the equivalent)

By Sonja Pace London 30 April 2007 Five British men have been sentenced to life in prison for their involvement in an al-Qaida inspired plot to carry out bomb attacks across Britain. VOA's Sonja Pace reports from London on the outcome of the trial th

发表于:2018-12-08 / 阅读(328) / 评论(0) 分类 2007年VOA标准英语(四月)

WHO: Balanced Approach for New Bird Flu Virus Strain In 2011, scientists discovered they had created a highly contagious and deadly form of H5N1 commonly called avian or bird flu. When the discovery was announced, debate erupted over whether the rese

发表于:2018-12-08 / 阅读(282) / 评论(0) 分类 VOA标准英语2011年(十二月)

AA: I'm Avi Arditti with Rosanne Skirble, and this week on WORDMASTER: reduced forms in spoken American English. RS: We're talking about forms like whaddaya -- meaning what do you, as in whaddaya say? Whaddaya Say? is also the title of a popular teac

发表于:2018-12-30 / 阅读(227) / 评论(0) 分类 词汇大师(Wordmaster)

A: I was wondering if someone in your office could help me with a question I have about my payment. B: I would be happy to answer any questions you might have. A: My paycheck seems to be smaller than the one I received last week. B: What about income

发表于:2018-12-30 / 阅读(266) / 评论(0) 分类 失业英语对话

A: I have a question about my payment and need someone to help me. B: Yes, I would be happy to answer a question about payment. What do you need help with? A: I cant figure out why my paycheck this week is smaller than last weeks. B: Did you generate

发表于:2018-12-30 / 阅读(249) / 评论(0) 分类 失业英语对话

A: Is there someone I can talk to about a payment question? B: Yes, we can handle that here. How can I help you? A: My paycheck that just arrived is less than last weeks check. B: Did you work at all during the last pay period? A: Yes, actually, I di

发表于:2018-12-30 / 阅读(249) / 评论(0) 分类 失业英语对话

The old man drove to Burger-Burger. He was 82 years old. It was late at night. It was 11:30 p.m. He was hungry. He wanted something to eat. He went to the drive-through. He ordered a Double Double Burger-Burger. He ordered large fries. He ordered a l

发表于:2019-01-02 / 阅读(222) / 评论(0) 分类 简单慢速英语阅读

Who and whom have to be two of the most difficult words in English. Luckily, we've already spent two articles on the ins and outs. Unfortunately, though, some people are still confused. They may even find themselves agreeing with William Safire, who

发表于:2019-01-02 / 阅读(304) / 评论(0) 分类 英语语法 Grammar Girl

Grammar Girl here. It was almost exactly a year ago when I did the first show about who versus whom. In that show I only covered the simple cases, and lately I've been getting questions that made me think I should delve deeper into the topic. So toda

发表于:2019-01-02 / 阅读(445) / 评论(0) 分类 英语语法 Grammar Girl

By Meredith Buel Washington 18 April 2007 A closely divided U.S. Supreme Court has upheld a ban on a controversial abortion procedure. VOA correspondent Meredith Buel has details from Washington. Pro-abortion demonstrators in front of the US Supreme

发表于:2019-01-12 / 阅读(292) / 评论(0) 分类 2007年VOA标准英语(四月)

By Nico Colombant Abuja 20 April 2007 Violence and delays are marking the hours before Saturday's (today's) presidential vote in Nigeria. Militant leaders in the oil-rich but restive south are vowing to disrupt the process. VOA's Nico Colombant repor

发表于:2019-01-12 / 阅读(230) / 评论(0) 分类 2007年VOA标准英语(四月)

By Nancy-Amelia Collins Jakarta 22 November 2006 An Indonesian militant has received a life sentence for harboring a top terrorist, and another man was sentenced to six years in jail for his links with terrorists. Subur Sugiarto, center, is escorted

发表于:2019-01-12 / 阅读(313) / 评论(0) 分类 2006年VOA标准英语(十一月)

The Asian Development Bank says Asia needs to balance its growth to prevent damage from future crises like the global economic slow-down. The bank has pledged to increase funds to strengthen growth. The Asian Development Bank is holding its annual m

发表于:2019-02-02 / 阅读(229) / 评论(0) 分类 VOA标准英语2009年(五月)

By Lisa Schlein Geneva 03 October 2006 Unidentified children of farm laborers, who faces eviction, inside their home near Messina, South Africa, in February 2005 A new report says the practice of forced evictions is increasing dramatically in Africa

发表于:2019-02-02 / 阅读(299) / 评论(0) 分类 2006年VOA标准英语(十月)

Oscar: How are you adjusting to being a single parent? Penny: It hasnt been easy, but Paul and I are trying to be as civil as possible. We worked out joint custody so that Mina will get quality time with both of us. Still, its been an adjustment for

发表于:2019-02-07 / 阅读(231) / 评论(0) 分类 地道美语播客
学英语单词
activate user
Acuformis Prevot
alla breve
alteration of trim
anterior horn of spinal cord
armor-
azed
Bacterium aeruginosum
barrelages
behind the bars
bench-scale testing
Benioff extensometer
binocular bandaging
boom dog
British North Borneo
Bunkeflo
Callas, Maria (Meneghini)
chertiest
cisconfiguration
co-evolved
code test
come to ... sense
common form
concentric transmission line
conspire together
counterspectrometer
Craigdarroch
crispy critters
cutting of components
cyclopelta obscura
dandruff
Daphnis
death of a salesman
depictures
dilucidly
disfavourite
disintegration constant
dual character of labo(u)r
Dunnet Head
ectostylids
electronic eavesdropping
elegant crested tinamou
ellert
emissarium condylicum
ensts
epistemonical
esker
externally specified index operation
family-photo
femble
friction gearing
genus Phalaenopsis
Georgiyevka
grafites
guillotine shutter
H and V contour correction
hawkin
hepatitis cs
hexarch
incorroborated
indicating lamp
ingrossing
intermediate text block
Kaifenheim
leptura taranan
littin
loxophthalmus
married operation
mcs (megacycles per second)
naval
Neualbenreuth
noiselessnesses
non-toxic aldehydes
optical soundtrack
orage
outs-of-the-way
overapproximates
overglance
pentangles
phosphoribosyltransferases
plongeur
poniard
prep
propidene
pump set
residual amplitude section
Russian dolls
samoensis
satellite planning data
scrape by
short-stop baths
slide gate
smothering arrangement
soundborad
stagiras
surface electrolytic marking machine
tue-sat
turn over sth
Vinh Tuy
vitaminD1