试题与答案

为了区别化妆品中的颗粒与菌落,可在每100ml营养琼脂中加入1ml、0.5%的A.T

题型:单项选择题

题目:

为了区别化妆品中的颗粒与菌落,可在每100ml营养琼脂中加入1ml、0.5%的

A.TTC溶液
B.EDTA
C.氢氧化钾
D.枸橼酸钠
E.磷酸氢钾

答案:

参考答案:A

解析:化妆品一般由多种物质混合而成,在进行细菌测定前虽然经过处理,但有时还会存在极难溶解的颗粒,颗粒易与细菌菌落相混,影响计数的准确性。可在营养琼脂中,加入氯化三苯四氮唑(TTC),培养后如系化妆品的颗粒,不见变化,如为细菌,则生成红色菌落。

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题型:单项选择题

Although there are many skillful Braille readers, thousands of other blind people find it difficult to learn that system. They are thereby shut (1) from the world of books and newspapers, having to (2) on friends to read aloud to them.

A young scientist named Raymond Kurzweil has now designed a computer which is a major (3) in providing aid to the (4) .His machine, Cyclops, has a camera that (5) any page, interprets the print into sounds, and then delivers them orally in a robot-like (6) through a speaker. By pressing the appropriate buttons (7) Cyclops’s keyboard, a blind person can "read" any (8) document in the English language.

This remarkable invention represents a tremendous (9) forward in the education of the handicapped. At present, Cyclops costs $ 50,000. (10) , Mr. Kurzweil and his associates are preparing a smaller (11) improved version that will sell (12) less than half that price. Within a few years, Kurzweil (13) the price range will be low enough for every school and library to (14) one. Michael Hingson, Director of the National Federation for the Blind, hopes that (15) will be able to buy home (16) of Cyclops for the price of a good television set.

Mr. Hingson’s organization purchased five machines and is now testing them in Maryland, Colorado, Iowa, California, and New York. Blind people have been (17) in those tests, making lots of (18) suggestions to the engineers who helped to produce Cyclops.

"This is the first time that blind people have ever done individual studies (19) a product was put on the market," Hingson said. "Most manufacturers believed that having the blind help the blind was like telling disabled people to teach other disabled people. In that (20) , the manufacturers have been the blind ones.

1()

A.up

B.down

C.in

D.off

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