石墨烯是由碳原子构成的单层片状结构的新材料(结构示意图如下),可由石墨剥离而成,

题型:选择题

问题:

石墨烯是由碳原子构成的单层片状结构的新材料(结构示意图如下),可由石墨剥离而成,具有极好的应用前景。下列说法正确的是

[ ]

A.石墨烯与石墨互为同位素

B.0.12g石墨烯中含有6.02×1022个碳原子

C.石墨烯是一种有机化合物

D.石墨烯中的碳原子间以共价键结合

考点:同位素碳单质及化合物共价键
题型:选择题

下列地理事物不在亚洲的是(  )

A.北半球的“寒极”

B.世界“雨极”

C.世界最长的山脉

D.世界最深的淡水湖

题型:选择题

China launched its fifth Beidou orbiter into space on Sunday morning, moving it one step closer to its goal of building a navigation(导航) and positioning satellite network.

The Beidou, or Compass, system is being built to rival the US-developed GPS, the European Union's Galileo and Russia's Global Navigation Satellite System. It can allow travelers, drivers and military officials to know their locations.

The fifth orbiter was launched on top of a Long March 3A carrier rocket at 5:30 am on Sunday from Xichang of Southwest China's Sichuan province.

It is the third Compass satellite launched this year, following launches on Jan 17 and June 2.

The short interval of less than two months since the last launch demonstrated that "the country is stepping into a busy period of launching the Compass satellites", an unnamed official in charge of the project said last month.

The first two orbiters were launched in 2007 and 2009 respectively.

Sun Jiadong, the Beidou program's chief designer, said on June 21 in a TV interview that China would launch 13 to 15 Beidou navigation satellites into orbit by 2012 to form a network that provides regional service covering the neighboring areas.

And in about 10 years, the network would be expanded to include more than 30 satellites covering the globe, he said.

The system is a crucial part of the country's space infrastructure for providing navigation and positioning services in transportation, meteorology, petroleum prospecting, forest fire monitoring, disaster forecasting, telecommunications and public security.

In addition, a global positioning system is crucial to any country's national security and defense, said Ran Chengqi, an official in charge of the program, referring to the fact that the US initially built its GPS system for military purposes.

It is unimaginable for China to go without such a system, he said.

Earlier reports cited(引用) Song Xiaojun, a Beijing-based military expert, as saying that 90 percent of the world's current weapons systems need a global positioning system.

小题1:This news report was probably released           .

A.in January, 2010

B.in June, 2010

C.in July, 2010

D.in August, 2010小题2:The Compass System is expected to finally cover     in the future.

A.China

B.China and its neigh boring areas

C.Asia, Europe and Oceania

D.the earth小题3:At the very beginning, the GPS system was built to help      .

A.military officers to judge their locations

B.travelers to know their locations

C.drivers to reach their destinations easily

D.hunters to find wild animals smoothly

题型:选择题

优先股票不同于普通股票,它有(  )的特征。

A.股息率固定

B. 股息分派优先

C. 剩余资产分配优先

D.一般无表决权

题型:选择题

躯体运动区主要位于()。

A.中央后回和中央旁小叶的后部

B.中央后回和中央旁小叶的前部

C.中央前回和中央旁小叶的后部

D.中央前回和中央旁小叶的前部

E.中央前回和中央旁小叶的后部

题型:选择题

外阴基底细胞癌()

A.来源于宫颈黏膜柱状黏液细胞,分泌大量黏液,细胞异型,极性消失

B.镜下表皮增厚以棘细胞层和基底细胞为主

C.由成纤维细胞增生而成,镜下见波浪状或相互盘绕的胶质囊和成纤维细胞

D.镜下见肿瘤组织自表皮基底层长出,细胞成堆伸向间质,有黏液变性

E.镜下见平滑肌细胞增生,细胞排列紊乱,核异型,核分裂象大于5个/HP

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