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问题 问答题

太阳光或火光能给我们带来温暖，那么不发光的物体能给我们带来温暖吗？    

请同学们先听一下几位同学的讨论。    

小明：我觉得不能，因为物体不发光，只能给我们带来温暖。    

小华：我感觉能，小明的观点不对，因为在冬天，我们的教室里的暖气片没有发光，但是能给我们带来温暖。    

小宇：我也同意小华的观点，可是这个不发光的暖气片为什么能给我们带来温暖呢？

请同学们再阅读教材上的“红外线”，你一定会帮助小宇解决问题，同时总结一下红外线的作用有哪些？

答案

物体温度升高，它辐射的红外线会大大增强，利用这一特点可以用来诊病或制成红外线夜视仪；热作用强是红外线的主要特性，即各种物体在吸收了红外线后温度要升高，利用这一特点可用于红外线加热物品，例如利用红外线来烘烤、取暖、理疗等；红外线的穿透能力强，利用这一特点可以来遥控、红外遥感，还可用在地球勘测、监控灾害、天气预报、军事方面等。

单项选择题 A1/A2型题

高纤维膳食不适用于（）。

A.高血压

B.糖尿病

C.食管静脉曲张

D.乳腺癌

E.功能性便秘
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单项选择题

Phyllis Wheatley is regarded as America’’s first black poet. She was born in Senegal, Africa, about 1753 and brought to America aboard a slave ship at about the age of seven. John and Susannah Wheatley bought her for three pounds at a slave auction in Boston in 1761 to be a personal servant of Mrs. Wheatley. The family had three other slaves, and all were treated with respect. Phyllis was soon accepted as one of the family, which included being raised and educated with the Wheatley’’s twin 15-year-old children, Mary and Nathaniel. At that time, most females, even from better families, could not read and write, but Mary was probably one of the best educated young women in Boston. Mary wanted to become a teacher, and in fact, it was Mary who decided to take charge of Phyllis’’s education. Phyllis soon displayed her remarkable talents. At the age of twelve she was reading the Greek and Latin classics and passages from the Bible. And eventually, Mrs. Wheatley decided Phyllis should become a Christian.At the age of thirteen Phyllis wrote her first poem. She became a Boston sensation after she wrote a poem on the death of the evangelical preacher George Whitfield in 1770. It became common practice in Boston to have "Mrs. Wheatley’’s Phyllis" read poetry in polite society. Mary married in 1771, and Phyllis later moved to the country because of poor health, as a teacher and caretaker to a farmer’’s three children. Mary had tried to interest publishers in Phyllis’’s poems but once they heard she was a Negro they weren’’t interested.Then in 1773 Phyllis went with Nathaniel, who was now a businessman, to London. It was thought that a sea voyage might improve her health. Thirty-nine of her poems were published in London as Poems on Various Subjects, Religious and Moral. It was the first book published by a black American. In 1775 Phyllis wrote a poem extolling the accomplishments of George Washington and sent it to him. He responded by praising her talents and inviting her to visit his headquarters. After both of her benefactors died in 1777, and Mary died in 1778, Phyllis was freed as a slave. She married in 1778, moved away from Boston, and had three children. But after the unhappy marriage, she moved back to Boston, and died in poverty at the age of thirty.

The word "respect" in Paragraph 1 is closest in meaning to________.

A．consideration

B．disregard

C．punishment

D．behavior
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