题干

下列装置能够组成原电池并发原电池反应的是(    )       

A:     

B:     

C:     

D:

上一题 下一题 0.0难度 选择题 更新时间:2020-04-09 11:47:58

答案(点此获取答案解析)

C

同类题2

阅读下面文章,完成下列小题。

阡陌交通的现代立交桥

       “有人之处必有水,有水之处必有桥。”早在千年之前,就已传颂的这句话,让我们明白了桥的重要。从《水经注》中的旅人桥,又到闻名世界的赵州桥,以及永定河上的卢沟桥,他们都是我国古代劳动人民智慧和心血的结晶。

       而今天,已经不再是那个“之乎者也”的时代了,随着科技的飞速发展,“有人之处必有水”已经不一定了,高新科技使人能在任何地方居住。“有水之处必有桥”已经不再受用了。水下可修通道;而无水之处,一座座雄伟的立交桥拔地而起。

       我国的城市几乎都有着立交桥,它像一座城市的皮带,连接着每个地方。随着城市人口的急剧增加和各式车辆的日益增多,平面相交的路口相当拥挤,所以各大城市就兴建了许多立交桥,用空间分隔的方法消除交叉路口人流、车流的冲突。有了立交桥,城市交通开始走向了立体。

       立交桥的形式多样,因为鉴于它陆地入口、出口的设计空间大,自然也就显得与一般桥更不同了。

       海尔立交桥是立交桥中的佼佼者,他是继杭州路立交桥、流亭立交桥、海信立交桥之后的又一大型立交桥。它起海尔路,北至合肥路,南至同安路,全长1 657米。其中跨线主桥全长312米,以东372米,以西560米。主线为双向八车道。海尔路因为它在原27米行道的基础上改为31米行道,总宽为44米。立交桥采用全苜蓿叶形。从空中俯视,它宛如比翼齐飞的一对蝴蝶,正在青岛这朵花上休息。它是青岛市最为亮丽的一道风景!

       近几十年来,有了立交桥,城市环线和高速公路网的连接畅通无阻。它使交通不再繁忙,它是我们城市必不可少的朋友,也是我们伟大祖国走向繁荣富强的见证!

同类题3

根据短文理解,选择正确答案。

Do you like spicy food?

    What's your opinion on spicy food? Some people cannot handle even the smallest amount of chili-red pepper-in their dinner while others can't get enough of it.

    Scientists have long been puzzled by why some people love chili while others loathe it. Plenty of research has been done on the subject, dating as far back as the 1970s. Previous results showed that a love of chili is related to childhood experiences, and cultural influences affect our taste buds too. But the latest study has found that a person's love of spicy food may be linked to his or her personality more than anything else, CBC News reported.

    'We have always assumed that liking drives intake-we eat what we like and we like what we eat. But no one has actually directly bothered to connect these personality traits with intake of chili peppers,' said Professor John Hayes from Pennsylvania State University, who led the study.

    But before you look at the study, you should first know that “spicy” is not a taste, unlike sour, sweet, bitter and salty. It is, in fact, a burning sensation that you feel on the surface of your tongue. This got scientists thinking that maybe a love of spicy food is brought about by people's longing for thrill, something they usually get from watching action movies or riding a roller coaster.

    In the study, 97 participants, both male and female, were asked to fill out questionnaires about certain traits of their personality, for example, whether they like new experiences or tend to avoid risks. They were then given a glass of water with capsaicin, the plant chemical that makes a chili burn, mixed into it.

    By comparing the answers to the questionnaire and what participants said they felt about the spicy water, researchers found that those who tended to enjoy action movies or take risks were about six times more likely to enjoy the spicy water.

    Interestingly, we used to believe that the reason some people can withstand spicy food is that their tongues have become less sensitive to it. However, this latest study has found otherwise. “It's not that it doesn't burn as badly, it's that you actually learn to like the burn,” Hayes explained.