经济发展从“又快又好”迈向“又好又快”，最为关键的是 A．依靠科技进步，转变经济

诊断单纯疱疹脑炎最可靠的依据是()

A．脑电图

B．脑组织活检

C．头MRI

D．对CSF标本进行聚合酶链反应

E．血常规

1 mol气态钠离子和1 mol气态氯离子结合生成1 mol氯化钠晶体释放出的热量为氯化钠晶体的晶格能。下列热化学方程式中，能直接表示出氯化钠晶体的晶格能的是 [ ]

A.Na(g)-e^- = Na⁺(g) △H

B.Na(s)+2Cl₂(g) = NaCl(s) △H

C.1/2Cl₂( g) = Cl(g) △H

D.Na⁺(g) +Cl^-(g) = NaCl(s) △H

阅读理解。

     WASHINGTON--Chinese Vice-President Xi Jinping arrived at Andrews Air Force Base in

Washington,February 13,2012．Vice-President Xi Jinping said he would explore important

problems in an active and practical manner with his America hosts on Monday during his five-day

official trip here after arriving at Andrews Air Force Base in the afternoon．

     In a written statement given upon his arrival,Xi said as the international situation experiences

complex and complete changes,China and the United States have more extensive common

interests and shoulder more important common responsibilities on the present world stage.

     The purpose of the current visit is to "carry out the important consensus reached by President

Hu with President Obama during his visit to the United States in January last year and to advance

the building of the China-US cooperative partnership based on mutual respect and mutual benefit",

said Xi.

     According to Xi,bilateral(双边的)relations have moved forward in spite of some twists and turns

during the past several decades．

      "This has brought enormous benefits to our two countries and two peoples,and has had a positive,

far-reaching impact on peace,stability and the prosperity of the Asia-Pacific region and the world at

large"．

     Xi said that"whether we can seize opportunities,tackle challenges and build a cooperative partnership

at the new historical starting point matters to the future of our two countries and the world as a whole．"

     Xi said he looks forward to engaging in extensive dialogue and exchanges with Americans from

various sectors to enhance cooperation and strengthen friendship．

      Xi is scheduled to meet US senior government officials,including Henry Kissinger,Brent Scowcroft,

Zbigniew Brzezinski,Madeleine Albright and Henry Paulson this evening to listen to their advice on

China-US ties．

     Meetings between Xi and US Vice-President Biden and President Obama are scheduled on Tuesday.

1．The passage mainly tells us        .

A．Xi's five-day official trip                    

B．China-US cooperative partnership

C．Xi is set to discuss important bilateral problems

D．China and the US have more common interests

2．It can be inferred from the second paragraph that      ．

A．the current world stage remains peaceful  

B．China and US should build the cooperative partnership

C．Xi himself wrote a statement about his arrival    

D．China and the US have the equal rights

3．The underlined word"consensus"in Paragraph 3 means      ．

A．agreement    

B．opinion    

C．partnership

D．benefit

4．According to the passage,bilateral relations between China and US have experienced        ．

A．enormous dialogues  

B．extensive exchanges  

C．many challenges

D．various hardships

5．What is Xi's attitude towards the visit?

A．Respectful．    

B．Optimistic．    

C．Approving．

D．Expectant．

某公司拟实施某项技术改造项目，预计需要新投资5000万元，拆除旧厂房设备将损失300万元，若这些厂房设备的残值为40万元，则该项目的总投资为（）万元

A．4660 

B．4760 

C．5260 

D．5340

在萃取分离中，只要分配比大，萃取效率就高。( )