下列因素中会使荧光效率下降的因素是() A.激发光强度下降 B.溶剂极性变大 C.温

题型:单项选择题 A1型题

问题:

下列因素中会使荧光效率下降的因素是()

A.激发光强度下降

B.溶剂极性变大

C.温度下降

D.溶剂中含有卤素离子

考点:广西公共卫生住院医师规范化培训卫生化学卫生化学题库
题型:单项选择题 A1型题

(12分)某研究性学习小组的同学用芭乐做成水果电池,并设计了 一个如图所示的电路来测定该水果电池的电动势和内电阻。实验中记录下电阻箱的电阻值和对应电流计示数,将数据填在如下的表格中。已知电流计内阻为Rg=500Ω

     

①甲、乙两同学利用图象法处理实验数据。甲同学作出的图象如图A所示,乙同学作出的图象如图B所示,你认为哪个同学作的图象对本问题的研究更科学_______(填“A”或“B”),其理由是:______。

②利用你认为科学的图象,得出该水果电池的电 动势为______V,内阻为______Ω。

③完成实验后,该研究性学习小组的同学初步得出了水果作为 电池不 实用的物理原因是______。

题型:单项选择题 A1型题

My name is Ralph and I am 42 years old. I work in a factory that I enjoy very much. On May 27, 1999, I was working on an automatic machine. While working my hand was pulled into the machine and my middle finger on my right hand was ripped off. I had surgery to replace what was left of the finger and now I have a finger that is almost as long as my index finger.

Over the years I have been very blessed for a full and healthy life. Most of all, blessed for having my wife. We have grown together and grown in our faith. Life is going to go on with or without my finger. I was not going to let this take over my life and I pushed to go back to work and got light duty.

This was where my lesson began. When I returned to work, I started getting comments and some teasing from people asking me if it was worth losing my finger over a pack of cigarettes. Someone started a rumor that I had dropped a pack of cigarettes and reached down to pick them up and that is how I lost my finger. This is not true. This rumor hurt more than losing my finger in that machine. Everyone was called in to a meeting to resolve this matter and get the story straight. I had to share my lesson.

We can ruin a person’s life by just a few bad words. There is an old saying that I will never forget: “Words and water are easily poured, but impossible to recover.” So please remember to watch what you say.

小题1:According to the author, his index finger on his right hand is almost as long as ________.

A.his middle finger on his right hand

B.his middle finger on his left hand

C.his thumb on his right hand

D.his thumb on his left hand小题2:From the second paragraph, we know that the author ________.

A.was not happy with a short finger

B.had a good relationship with his wife

C.didn’t want to work any more in the factory

D.wanted to find an important job小题3:The rumour about the author is that he lost his finger ________.

A.when he was picking up a pack of cigarettes that had fallen into the machine

B.because he was not careful and smoked when running the machine

C.because he was too sleepy to operate the machine properly

D.when he was reaching down to fix something wrong in the machine小题4:Which of the following can match the underlined sentence in the last paragraph?

A.Nothing is really beautiful but truth.

B.Bad words are meaningless.

C.Lies having short legs can do harm.

D.Words cut deeper than swords.

题型:单项选择题 A1型题

肺囊性纤维化

A.多发生于左下叶支气管
B.好发部位位于上叶尖后段或下叶背段
C.可见段支气管近端的扩张
D.常伴鼻窦炎及内脏转位
E.血清内可含有抑制支气管柱状上皮细胞纤毛活动的物质

题型:单项选择题 A1型题

当大学生选修某门课程时,面临课程有趣喜欢,但又讨厌作业报告太多的心理冲突时,是属于多重趋避冲突。

题型:单项选择题 A1型题

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