题目内容
听力原文：M: Did you watch undersea Discover), last night？
W: No, I missed it. Did you？
M: Yeah, it was pretty good...It was about barnacles.
W: Hmm.
M: You know how they stick themselves to stuff in the ocean ... like rocks or boats？
W: Uh—huh.
M: Well, they do that when they're young, and then they stay in the same place forever.
W: It figures. Have you ever tried removing one of those things. Last summer I tried to scrape some off a pier...I had to give up after a while. You'd think they wouldn't be able to stick like that undcrwater.
M: That's one. reason scientists are-trying to figure out what their glue's made of. It's one of the strongest adhesive in nature, and it's a natural protein, so it probably wouldn't be harmful like some synthetic glues.
W: Really？
M: Yes. these biomedical researchers were talking about its possible uses. Orthopedists could use it for mending broken bones; or it could be used in dentistry.
W: I wish I'd seen that.
(23)
查看答案
搜索结果不匹配？点我反馈
更多问题
A．She runs a farm.B．She studies English.C．She teaches meteorology.D．She leads wilderne
某市区一固定资产项目的施工现场图示如下，请根据图示回答以下问题：
因生活区尚未建成，可以将施工人员暂时安排在()居住。
A．They eat protein.B．They never move from one location.C．They cause erosion of rocks.D
If you live in a large city, you are quite familiar with some of the problems of noise, but, because of some of its harmful effects, you may not be aware of the extent of its influence on human behavior. Although everyone more or less knows what noise is, i. e., it is sounds that one would rather not hear, it is perhaps best to define it more precisely for scientific purposes. One such definition is that noise is sounds that are unrelated to the task at band. Thus stimuli (刺激物)that at one time might be considered relevant will at another time to be considered noise, depending on what one is doing at the moment. In recent years there has been a great deal of interest in the effects on human behavior, and concepts such as "noise pollution" have arisen, together with movements to reduce noise.
Exposure to loud noises can definitely produce a partial or complete loss of hearing, depending on the intensity, duration, and frequency composition of the noise. Many jobs present noise hazards (危险), such as working in factories and around jet aircraft, driving farm tractors, and working in music halls where rock bands are playing. In general, continuous exposure to sounds of over 80 decibels can be considered dangerous. Decibel values correspond to various sounds. Sounds above 85 decibels may, if exposure is for a sufficient period of time, produce significant hearing loss. Noise can have unexpected harmful effects on performance of certain kinds of tasks, for instance, if one is performing a watch keeping task that requires vigilance (注意), in which he is responsible for detecting weak signals of some kind (e. g. , watching a radar screen for the appearance of aircraft).
Communicating with other people is unfavorably affected by noise. If you have ridden in the rear of a jet transport, you have noticed that it was difficult to carry on a conversation at first, and that, eventually you adjusted the loudness of your speech to compensate for the effect. The problem is noise.
Noise differs from sound in that ______.
微信支付 
支付宝支付