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

题型:选择题

问题:

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=

考点:X射线α、β、γ射线
题型:选择题

均称体型正常人肝叩诊相对浊音界,哪项是错误的( )

A.右锁骨中线第5肋间
B.右锁骨中线上下径为9~11cm
C.右腋中线第8肋间
D.右肩胛线第10肋骨水平
E.肝绝对浊音界比相对浊音界低1~2肋间

题型:选择题

腹部触诊时应从主诉_______区域开始,最后检查_______部位。肠鸣音活跃、响亮、气过水声伴腹痛提示_______,肠鸣音消失为_______表现。

题型:选择题

随着蒸汽初参数的提高,厂用电率也降低.

题型:选择题

Government officials reported three new cases of mad cow, bringing the total so far this year to 99. Last year, France recorded just 31 cases of the mad cow disease. The rising numbers are in part (1) a new testing program that focuses on cows that are most (2) . That program has (3) 39 cases. But still 60 new cases were identified in the usual way, (4) were found in 1999. Many scientists (5) that this year, five years after safety precautions were (6) , the number of cases would be (7) .

The rise in cases has (8) some scientists to question whether the disease can be transmitted in ways not yet understood. Scientists are still (9) the disease, first recognized in cows in 1986.

It appears that it is not caused by a bacteria, virus or fungus, but (10) infectious particles called prion, perhaps (11) a virus or other agent. The disease kills cells in the brain, (12) it spongy and full of holes.

France has taken more steps to (13) safety than most European countries, (14) refusing to take English beef (15) the European Union. But some scientists believe that France has not been (16) in imposing the ban on feed that (17) animal pans.

Some French officials hope that the sudden interest in mad cow disease will mean that French consumers will become educated about it, thereby recognizing that French beef is actually (18) controlled. Every cow is given a passport at birth, and extensive information about its parentage and (19) it was raised must be (20) to any slaughterhouse. When a diseased animal is found, the entire herd is destroyed.

10()

A. stems from

B. developed in

C. grew out of

D. generated from

题型:选择题

螺纹锁紧式换热器有如下几个突出优点()。

A、密封可靠

B、拆装方便

C、金属用量少

D、结构紧凑.占地面积小

更多题库