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问题 单项选择题

在消声降噪工程中，以下措施不能提高阻性消声器低频段的消声效果（）。

A.适当增加消声片的厚度

B.增加气流通道面积

C.适当提高多孔吸声材料的填充密度

D.在吸声层后面留一定深度的空气层

答案

参考答案：B

解析：增加消声片的厚度，提高多孔吸声材料的填充密度以及在吸声层后面留一定深度的空气层都是提高阻性消声器低频段的消声效果的措施。

阅读理解
阅读理解。
     Some 30 million Americans suffer from insomnia. Here, our expert panel provides you with four different
solutions for getting some rest:
Neil B. Kavey, MD,
Director, Sleep
Disorders Center,
New York Presby-
terian Hospital
The sleep specialist. Try behavior changes
and proper use of medication. At night, keep
away from bright light. In the morning, open
the shades and go out for a walk, to tell your
brain, "This is, the beginning of the day."
You can try OTC sleep aids, but if you suffer
for more than three weeks, see a doctor.
Drugs are safe when used properly, and better
than the consequences of not sleeping.
Cerald Lemole,
MD Associate
Medical Director,
Christiana Care
Center for Heart
and Vascular Heal-
th, Wilmington,
Delaware.
The alternative source. Stress often plays a
role in insomnia, so try to change your reaction
to it. Don't exercise or eat at the end of the day,
and avoid or limit caffeine, alcohol and nicotine.
Enjoying a warm bath can help. Also, try taking
l,000 mg of calcium (钙) (it may calm your
muscles and nerves, helping you sleep ).
Lisa Derosimo,
MD, Owner, The
Weight and
Wellness Center,
Jupiter, Florida
The nutritionist. Go to bed and get up at the same
time daily. Keep your room dark and quiet, and
remove distractions (no working in bed). Have a
cup of herbal (草药) tea, such as chamomile (甘菊),
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and low-fat protein feel better and sleep better.
Sandra McLanah-
an, MD, Medical
Director, Integral
Health Center, Buckingham,
Virginia
The mind/body pro. Lying in bed, starting from your
legs and moving up to your head, tense your muscles
one at a time, then release. Your body will feel more
relaxed, like a rubber band after it's been stretched.
And try alternate-nostril (鼻孔交换的) breathing. Exhale
(呼气) through one nostril, using your fingers to close
the opposite nostril. Breathe in and out; then switch
back and forth.
1. What does the underlined word"insomnia" in the second paragraph mean?
A. Late stay.
B. Sleeplessness.
C. Tiredness.
D. Breath trouble.
2. Who thinks medicine is an important factor in keeping a good sleep?
A. Kavey
B. Lemole.
C. Derosimo.
D. McLanahan.
3. According to Lisa Derosimo, what results in a good sleep?
A. Having a balanced diet.
B. Keeping your sleeping-room bright.
C. Taking enough medicine.
D. Having some fish in the evening.
4. From the passage we can infer that altemate-nostril breathing is a good way to _____.
A. breath deeply
B. build your body
C. exercise your nose
D. relax yourself
5. Gerald Lemole and Sandra McLanahan share the idea about the way of _____ to have a good sleep.
A. diet
B. relaxation
C. medicine
D. taking calcium
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选择题

2008年1月8日，中 * * 、国务院在北京隆重举行国家科学技术奖励大会，中 * * * * 、国家 * * 、中央军委 * * 胡 * * 向获得2007年度国家最高科学技术奖的中国科学院院士___________颁奖。[ ]

A．吴征镒  闵恩泽 

B．钱学深  闵思泽 

C．吴征镒  袁隆平 

D．钱学深  袁隆平
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