不属于CT机调试内容的是： A．X线输出量调试 B．探测器信号输出 C．检查床

2002年诺贝尔物理学奖中的一项，是奖励美国科学家贾科尼和日本科学家小柴晶俊发现了宇宙X射线源．X射线是一种高频电磁波，若X射线在真空中的波长为λ，以h表示普朗克常量，c表示真空的光速，以E和m分别表示X射线每个光子的能量和质量，则（　　） A．E=，m=0 B．E=，m= C．E=，m=0 D．E=，m=

铁、铝、铜是日常生活中使用最广泛的金属。

（1）上述三种金属中，人类最早大规模冶炼和使用的是____

（2）常温下一些金属的物理性质数据如下：

金属单质	铜	铝	锌	铁	铅
导电性（以银的导电性为100作标准）	99	61	27	17	7.9
密度/(g·cm-3)	8.92	2.70	7.14	7.86	11.3
熔点/℃	1083	660	419	1535	328
硬度（以金刚石的硬度为10作标准）	2.5~3	2~2.9	2.5	4~5	1.5

分析上述数据，碎石用的大锤常用铁制而不用铝制，原因是_____________________。

（3）金属铝与氧化铁在高温条件下能发生置换反应，其化学方程式为                                      。

（4）炼铁的原理是利用一氧化碳与氧化铁反应。在实验室里，可用下图所示装置进行实验：实验中玻璃管内的粉末由红色变为         色，该反应的化学方程式为                                            。

    

Every hour spent in watching TV, DVDs and videos as an adult reduces lifespan by almost 22 minutes, a study suggests. And viewing TV for an average of six hours a day can cut short your life by five years.

The research shows that a sedentary（久坐的） lifestyle is as bad for health as smoking and obesity, because of the dangers caused by inactivity and the greater opportunities it offers for unhealthy eating.

The researchers set out to calculate the overall risk to lifespan from watching television. Their research involved more than 11,000 people over the age of 25.

Writing in the British Journal of Sports Medicine, they concluded. "TV viewing time may be connected with a loss of life, which is similar to other major chronic disease risk factors such as physical inactivity and obesity."

The researchers, from the University of Queensland, used information from the Australian Diabetes, Obesity and Lifestyle Study, together with population and death rate data.

But they said: "Although we used Australian data, the effects in other industrialized and developing countries are likely to be similar, considering the large amounts of time spent watching TV and similarities in disease patterns." In the United Kingdom, the average amount of time spent watching TV is four hours a day, compared with five hours in the United States.

Earlier this year, a separate study suggested the risk of developing diabetes and heart disease, or dying early, rises by as much as 20 percent after just two hours a day in front of the box.

England's Chief Medical Officer, Sally Davies, said: "Physical activity offers huge benefits and these studies back what we already know - that a sedentary lifestyle carries additional risks. We hope these studies will help more people realize that there are many ways to get exercise."

小题1:We can learn from the passage that       .

A．whether you watch TV or not has nothing to do with how long you will live

B．if an adult watches TV for six hours every day, he will probably die five years earlier

C．physical inactivity and obesity won't shorten your life

D．a sedentary lifestyle offers huge benefits.小题2:The passage implies that _______.

A．The longer one watches TV every day, the shorter he lives.

B．The conclusion of the study is unbelievable because it's based on Australian data.

C．Watching TV does greater harm to health than smoking and obesity

D．Watching TV harms children as much as adults.小题3:What do we know from the last three paragraphs?

A．People in the United Kingdom watch TV longer than those in the United States.

B．That a sedentary lifestyle carries additional risks isn't supported by other studies.

C．Watching TV for two hours a day will increase the risk of illnesses or dying early by 20%.

D．Australian data is much different from that of other countries.小题4:The passage is intended to _______.

A．inform the readers of a research on watching TV

B．tell the readers large amounts of people often watch TV

C．tell the readers watching TV is also a good way to relax

D．warn the readers of the harm of watching TV and hope that they do sports

血气分析标本的采集和保存不正确的是

A．肝素抗凝
B．隔绝空气
C．立即分析
D．采集动脉血和静脉血均可
E．采血后将血液混匀

采用汇兑结算时，汇入银行对于向收款人发出取款通知，经过（）无法交付的汇款，应主动办理退汇。

A.10天

B.15天

C.1个月

D.2个月