问题 问答题 简答题

滑动轴承有哪些主要特点?

答案

参考答案:

滑动轴承的主要优点是:工作可靠,寿命长,运转平稳,噪声小,轴承承载能力大。其中液体摩擦滑动轴承适合高速大功率设备,而非液体摩擦滑动轴承结构简单,价格低,在要求低的设备中应用广泛。

滑动轴承的主要缺点是:液体摩擦滑动轴承的设计、制造和润滑要求高,结构复杂,价格高;非液体摩擦滑动轴承的摩擦损失大,磨损严重,易产生磨损和胶合失效。

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                                         Easy Ways to Keep Your Brain Sharp

    Everyone is forgetful, but as we age, we start to feel like our brains are slowing down a bit-and that

can be a very annoying thing.   1    Read on for some techniques worth trying.

    1.    2  

    People who regularly made plans and looked forward to upcoming events had a 50 percent reduced

chance of Alzheimer's disease (老年性痴呆症), according to a recent study.   3    Something as simple

as setting a goal to have a weekly coffee date with a friend will do. There's evidence that people who

have a purpose in life or who are working on long or short-term goals appear to do better. In other

words, keep your brain looking forward.

    2. Go for a walk.

    Mildly raised glucose(葡萄糖)levels can harm the area of the brain that helps you form memories

and physical activity can help get blood glucose down to normal levels. In fact, exercise produces

chemicals that are good for your brain.      4      

     3. Learn something new.

    Take a Spanish class online, join a drawing club, or learn to play cards. A study found that mental

stimulation limits the weakening effects of aging on memory and the mind. But the best thing for your

brain is when you learn something new and are physically active at the same time.    5   Or you can just

go dancing with your friends.

A. Focus on the future.

B. This can be especially harmful to the aged.

C. It should be something like learning gardening.

D. So take a few minutes each day to do some reading.

E. But don't worry if our schedule isn't filled with life-changing events.

F. Luckily, research shows there is a lot you can do to avoid those moments.

G. In other words, when you take care of your body, you take care of your brain.

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