问题 问答题

冷拉后的钢筋有哪些优点为什么说冷拉钢筋通过时效后才能充分体现冷拉的优点

答案

参考答案:冷拉后的钢筋在力学性能上可提高钢筋的强度约20%~25%,但塑性未明显变坏。通过冷拉还可增加原有钢筋的长度3%~8%,同时解决钢筋的除锈和调直问题。
冷拉后的钢筋,经过一定的时间后,才能使钢筋中的晶体被渗碳体分布在晶体滑动面上,进一步起到阻碍晶体滑动的强化作用,从而能提高钢材强度。这就是冷拉后的钢筋通过时效后提高强度的内在原因。

阅读理解

阅读理解。

    Studies have shown it takes a doctor about 18 seconds to stop a patient after he begins talking. 

    It was Sunday. I had one last patient to see. I came close to her room in a hurry and stood at the doorway.

She was an older woman, sitting at the edge of the bed, trying to put socks on her swollen(肿大的) feet. I

spoke quickly to the nurse, saw her chart saying she was in stable(稳定的) condition. I was almost in the

clear. 

   She asked if I could help put on her socks. Instead, I began a long speech that went something like this:

" How are you feeling? Your blood sugar and blood pressure (血压)were high but they're better today. The

nurse said you can't wait to see your son who's visiting you today. It's nice to have a family visit from far

away. I'm sure you really look forward to seeing him. "

    She stopped me with a serious voice. " Sit down, doctor. This is my story, not your story. "

    I was surprised and ashamed. I sat down. I helped her with the socks. She began to tell me that her only

son lived around the corner from her, but she had not seen him in five years. She believed that the pressure of

this caused greatly to her health problems. After hearing her story and putting on her socks, I asked if there

was anything else I could do for her. She shook her head and smiled. All she wanted me to do was to listen.

     Listening to someone's story costs less than expensive diagnostic(诊断的) testing but is key to healing

(痊愈).

     I often thought of what that woman taught me the importance of stopping, sitting down and truly listening.

And, not long after, unexpectedly, I became the patient, with a diagnosis of sclerosis(硬化症) at age 31. Now,

 20 years later, I sit all the time in a wheelchair.

     For as long as I could, I continued to see patients from my chair, but I had to give up my job when my

hands were influenced. I still teach medical students and other health care professionals, but now from the view

of doctor and patient.

    I tell them I believe in the power( 力量) of listening. I tell them I know firsthand that huge healing takes place within me when someone stops, sits down and listens to my story.  

1. What does"I was almost in the clear" mean?

A. I thought everything was clear.

B. I was about to finish my work.

C. I almost made myself understood.

D. I was very quickly out of her sight.

2. From the 4th paragraph, we can infer the woman ___from the way she said.

A. showed her anger and impatience

B. refused to listen to the doctor

C. liked giving orders to people

D. could not wait to break in

3. What is the best title of the passage?

A. Listening-a Powerful Medicine

B. An Unforgettable Experience

C. A Lesson Given by a Patient

D. Care—a Key to Treatment .

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