以金元素为主要成分的贵金属合金是() A.Au-Pt-Pd类合金 B.Au-Pd

题型:单项选择题 B型题

问题:

以金元素为主要成分的贵金属合金是()

A.Au-Pt-Pd类合金

B.Au-Pd-Ag类合金

C.Pd-Ag类合金

D.Pd-Cu类合金

E.Ti类合金

考点:口腔五官科主治医师口腔医学基础知识口腔医学主治医师基础知识模拟试题(一)
题型:单项选择题 B型题
已知cosα<0,那么α角终边的位置在(  )
A.第二象限或第三象限
B.第三象限或第四象限
C.第二象限或第三象限或x轴负半轴
D.第三象限或第四象限或y轴负半轴
题型:单项选择题 B型题
小明比小丽大,己知小明x岁,小丽y岁,8年后小明比小丽多(  )岁.
A.8B.x-yC.x-y+8
题型:单项选择题 B型题

阅读理解

     LOS ANGELES-Once in a blue moon there is one on New Year's Eve.Revelers (狂欢者) ringing in

2010 will be treated to a socalled blue moon.According to popular definition, a blue moon is the second

full moon in a month.But don't expect it to be blue-the name has nothing to do with the color of our

closest space neighbor.

     A full moon occurred on Dec.2,2009.It will appear again on Thursday in time for the New Year's

countdown.

     "If you're in Times Square, you'll see the full moon right above you.It's going to be that brilliant, " said

Jack Horkheimer, director of the Miami Space Transit Planetarium and host of a weekly astronomy TV

show.

      The New Year's Eve blue moon will be visible in the United States, Canada, Europe, South America

and Africa.For partygoers in Australia and Asia, the full moon does not show up until New Year's Day,

making January a blue moon month for them.

     However, the eastern hemisphere can celebrate with a partial lunar eclipse (月偏蚀) on New Year's

Eve when part of the moon enters the Earth's shadow.The eclipse will not be visible in the Americas.

      A full moon occurs every 29.5 days, and most years have 12 ones.On average, an extra full moon in

a month-a blue moon-occurs every 2.5 years.The last time there was a blue moon was in May 2007.

New Year's Eve blue moons are rarer, occurring every 19 years.The last time was in 1990.

     Blue moons have no astronomical significance, said Greg  Laughlin, an astronomer at the University

of California, Santa Cruz."' Blue moon' is just a name in the same sense as 'a hunter's moon'  or 'a

harvest moon', "  Laughlin said in  an email.

     The popular definition of blue moon came about after a writer for, Sky & Telescope magazine in

1946 misinterpreted (误解) the Maine Farmer's Almanac (历书) and labeled a blue moon as the

second full moon in a month.In fact, the almanac defined a blue moon as the third full moon in a season

with four full moons, not the usual three.Though Sky & Telescope corrected the mistake decades later,

the definition caught_on.

1. According to the popular definition, "a blue moon" means________.

A. the second full moon in a month

B. a moon which looks blue

C. a partial lunar eclipse

D. the second full moon in a year

2. In Japan, people can see a blue moon in________.

A. December,2009  

B. January,2010

C. May,2010  

D. July,2011

3. The next New Year's Eve blue moon is most likely to appear in________.

A. 2013  

B. 2018  

C. 2026  

D. 2028

4. The underlined phrase "caught on" means________.

A. understood  

B. got rare

C. became popular  

D. was out of date

5. Which of the following is the best title?

A. Blue moons have no astronomical value

B. Rare New Year's Eve "blue moon" to ring in 2010

C. Rare New Year's Day "blue moon" to celebrate New Year

D. A blue moon comes again

题型:单项选择题 B型题

药材呈圆柱形或略呈纺锤形,顶端有较短的芦头的药材为

A.三七
B.党参
C.天花粉
D.黄芩
E.桔梗

题型:单项选择题 B型题

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