问题 选择题

下列说法或做法正确的是(  )

A.可燃物达到着火点时一定都可发生燃烧

B.燃烧、缓慢氧化、爆炸等一定都是氧化反应

C.室内燃气大量泄漏时应立即立即打开换气扇通风

D.室内起火烟雾较浓,逃离时用湿毛巾捂住口鼻并尽量贴近地面

答案

A、可燃物燃烧必须与氧气接触、温度达到着火点,故错误;

B、物质在空气中发生燃烧、缓慢氧化、爆炸的共同点是都是与氧发生的氧化反应,并且会都放出热量,故错误;

C、室内燃气属于可燃性气体,与氧气接触,遇明火有爆炸的危险,故错误;

D、火灾时产生大量的有毒气体,一氧化碳,一氧化氮,这些气体比空气的密度小,所以会大量产生在上层空气中,所以人应尽量下蹲或者一匍匐前进;用湿毛巾捂住鼻子,可以有效的过滤空气中的有毒气体进入人体的呼吸系统,所以用湿毛巾捂住口鼻,并尽量贴近地面逃离,是自救的安全有效方法,故正确.

故选D.

填空题
单项选择题

Are you one of those who always fear whenever a dog is approaching If you are, you have got phobia ( a very p feeling of being afraid of something ). Of all human fears, phobias may be the most uncontrollable. They are most often caused by a particular situation or object. In general, pho- bias can mainly be divided into three varieties. To begin with, agoraphobia is a fear of staying in strange surroundings, for example, an unfamiliar place, or an open area. Social phobia refers to the anxiety people show when they have to stay or perform on social events, for instance, speaking in front of the class. Lastly, there are a wide range of specific phobias. People suffering from this kind of phobia are terrified of specific objects or creatures, such as spiders, perhaps to your surprise, clowns. Besides, there are about six hundred and fifty phobias listed by psychologists (心理学家) as yet.
Faced with their phobias, many people choose to do nothing but just escape the situations or objects they fear. Psychologists, however, warn that if not treated properly, this kind of anxiety will get worse, so that it may disturb the sleep pattern, cause physical symptoms, and finally affect their daily activities. As for treatment, clinical research has discovered that medicine for anxiety is not successful in curing phobias. However, the anxiety disorders can be efficiently treated through cognitive behavioral therapy (认知行为疗法) , through which patients are led to inspect the connections between their own fear and the situation or object, and then actively choose the acceptable treatments. Also, other treatments proved effective in reducing phobias are meditation, listening to calming music, and so on.

Which of the following statements about phobias is correct

A.Actors call help people to cure their phobias.

B.Phobias can be divided into six hundred and fifty types.

C.Those suffering from phobias may not sleep well or work normally.

D.Cognitive behavioral therapy demands little participation from patients.