外照射放射治疗用同位素的重要特性是() A.放射性比活度较高,r射线能量较高 B.放

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问题:

外照射放射治疗用同位素的重要特性是()

A.放射性比活度较高,r射线能量较高

B.放射性比火毒较低,半衰期较长

C.空气比释动能吕交大,半衰期较短

D.空气比释动能率较小,r射线能量较高

E.半衰期较长,r射线能量较低

考点:LA医师(放射治疗X刀伽马刀)LA物理师(伽马刀物理师)LA物理师(伽马刀物理师)题库
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等静压成型

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阅读理解。

      It was a winter morning, just a couple of weeks before Christmas 2005. While most people were warming

up their cars, Trevor, my husband, had to get up early to ride his bike four kilometers away from home to

work. On arrival, he parked his bike outside the back door as he usually does. After putting in 10 hours of

labor, he returned to find his bike gone.

      The bike, a black Kona 18 speed, was our only transport. Trevor used it to get to work, putting in 60-hour

weeks to support his young family. And the bike was also used to get groceries (食品杂货), saving us from

having to walk along long distances from where we live.

      I was so sad that someone would steal our bike that I wrote to the newspaper and told them our story.

Shortly after that, several people in our area offered to help. One wonderful stranger even bought a bike, then

called my husband to pick it up. Once again my husband had a way to get to and from his job. It really is an

honor that a complete stranger would go out of their way for someone they have never met before.

      People say that a smile can be passed from one person to another, but acts of kindness from strangers are

even more so. This experience has had a spreading effect in our lives because it strengthened our faith in

humanity (人性) as a whole. And it has influenced us to be more mindful of ways we, too, can share with

others. No matter how big or how small, an act of kindness shows that someone cares. And the results can

be everlasting.

1. Why was the bike so important to the couple? [ ]

A. They used it for work and daily life.

B. It was their only possession (财产).

C. It was a nice Kona 18 speed.

D. The man's job was bike racing.

2. We can infer from the passage that _____. [ ]

A. the couple worked 60 hours a week

B. people were busy before Christmas

C. the stranger brought over the bike

D. life was hard for the young family

3. What do the couple learn from their experience?[ ]

A. Strangers are usually of little help.

B. One should take care of their bike.

C. News reports make people famous.

D. An act of kindness can mean a lot.

4. From this story,we can see humanity is _____. [ ]

A. selfish

B. commercial

C. kind

D. cold-hearted

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新安装水轮发电机组应做哪些检查和试验?

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车载网络系统优点()

A.提高整车控制集成度

B.减少车身电器线束

C.提高信号传递精度

D.维修方便

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药品生产企业、经营企业、医疗机构在药品购销中账外暗中给予或收受回扣或其他利益的,药品生产企业、经营企业或者其代理人给予使用其药品的医疗机构负责人、药品采购人员、医师等有关人员以财物或其他利益的,由工商行政管理部门处以罚款的数额为

A.货值金额五至十倍的罚款
B.十万元以上二十万元以下的罚款
C.三十万元以上的罚款
D.一万元以上二十万元以下的罚款
E.收受贿赂的十倍罚款

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