下列关于β-折叠片层结构的叙述，正确的是（）。A.β-折叠常呈左手螺旋 B.β-折叠

发布时间：2017-05-19 18:42 │ 来源：www.tikuol.com

题型：单项选择题

问题：

下列关于β-折叠片层结构的叙述，正确的是（）。

A.β-折叠常呈左手螺旋

B.β-折叠只在两条不同的肽链间形成

C.β-折叠主要靠链间的氢键来稳定

D.β-折叠主要靠链间的疏水作用来稳定

E.β-折叠主要靠链内的氢键来稳定

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题型：单项选择题

阅读理解。

     Years ago,I lived in a building in a large city. The building next door was only a few feet away from
mine. There was a woman who lived there and whom I had never met, yet I could see her sitting by her
window each afternoon, sewing (缝纫) and reading.
     After several months had gone by, I began to notice that her window was dirty. Everything was
unclear through the dirty window. I would say to myself, "Why doesn't that woman clean her window?
It really looks terrible."
     One bright morning I decided to clean my flat,including cleaning the window.
     Late in the afternoon after I finished the cleaning, I sat down by the window with a cup of coffee for
a rest. What a surprise! The woman sitting by her window was clearly seen. Her window was clean!
    Then it dawned on me. I had been criticizing (批评) her dirty window,but all the time I was watching
hers through my own dirty window.
     That was quite an important lesson for me. How often had I looked at and criticized others through
the dirty window of my heart, through my own shortcomings (缺点)?
     From then on, whenever I want to judge someone, I ask myself first, "Am I looking at him through
my own dirty window?" Then I try to clean the window of my own world so that I can see others' world
more clearly.

1．The writer couldn't see anything early through the window because ______.

[ ]

A．the woman's window was dirty
B．his window was dirty
C．the woman lived far away
D．he was near-sighted (近视的)

2．After the writer finished the cleaning he was surprised to find that ______.

[ ]

A．the woman was sitting by her window
B．the woman's window was still dirty
C．the woman was cleaning her window
D．the woman's window was clean

3．The underlined part "it dawned on me" probably means "______".

[ ]

A．I began to understand it
B．it cheered me up
C．I could see myself through the window
D．it made me sad

4．Which of the following is TRUE according to the passage?

[ ]

A．Both the woman and the writer lived in a small town.
B．The writer often cleaned the window.
C．Both the woman and the writer worked as cleaners.
D．The writer never met the woman.

5．From the passage we can learn that ______.

[ ]

A．one shouldn't criticize others very often
B．one should often keep his windows clean
C．one should judge himself before he judges others
D．one should look at others through his dirty window

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题型：单项选择题

单杠杆式气动差压变送器量程调整范围比双杠杆差压变送器的量程调整范围（）。

A、大

B、小

C、差不多

D、无法确定

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汽车发动机工作时，缸体的温度很高，为确保发动机正常工作，需对缸体进行冷却．一般使用水来充当冷却剂，主要有如下考虑：①成本低廉、取材方便；②水的______比较大，在同等条件下吸热比较多，冷却效果好；③水在沸腾时，吸收热量，温度______，能确保缸体的温度不致升得过高．

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题型：单项选择题

采用（）方式来控制铜套厚度。

A、刮削

B、磨削

C、铣削

D、镗削

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题型：单项选择题

荷塘公司从月色公司购买真皮沙发2套，价款为2万元，双方签订合同，约定如发生纠纷可向北京仲裁委员会申请仲裁。交付后，荷塘公司发现该沙发并非真皮制成，便向仲裁委员会申请仲裁，请求退货。
请回答下列81～85题。

如果在仲裁中，月色公司提出沙发不是真皮是因为皮革公司提供的原料有假，则该皮革公司在仲裁程序中的身份是：( )。

A．证人

B．第三人

C．鉴定人

D．被申请人

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