按体积比2∶3混合的N2与CO2 112.8 g在标准状况下体积为( ) A.2

题型:选择题

问题:

按体积比2∶3混合的N2与CO2 112.8 g在标准状况下体积为(    )

A.22.4 L

B.44.8 L

C.67.2 L

D.89.6 L

考点:物质的量
题型:选择题

软交换系统中继网关主要针对传统的()网中的媒体流的汇接接入。

A.帧中继

B.ADSL用户

C.PSTN/ISDN

D.以太网用户

题型:选择题

阅读理解

     We often think of future. We often wonder what the world will be like in a hundred years' time.

      Think of space,  perhaps a permanent (永久的) station on the moon will have been set up. Perhaps

people will be able to visit the moon as tourists. Cheap rockets for space travel will have been developed, permitting long journeys throughout the solar system(太阳系). When that time comes, people will be

taking holidays in space and visiting other planets. Creat progress will have been made in medicine, too.

Perhaps a cure will have been discovered for the most terrible of all diseases-cancer. Pollution is a

problem we must solve. In a hundred years' time it will have been controlled.

     All the world will have been developed-even Antarctica. There will be large cities in Antarctica. We

already have supersonic (超音速的)  flight,  but in a hundred years' time we will have supersonic land

travel as well.

     We will have used up most of the earth's land tobuild our cities, so floating cities will have been built.

The Japanese already have plans for cities of this kind.And there will be cities under the sea. The first of

these will have been completed.       .

1. We will have developed _    in a hundred years' time, permitting long journeys all over the solar

    system.   

A. cheap rockets for space travel

B. a plane

C. a spaceship

D. a satellite

2. Man will also have supersonic land travel         .  

A. in a year

B. about half a century later

C.in the year 2050

D. about a century later

3. The last paragraph mainly talks about _         .   

A. we'll make good use of space on the earth

B. cities under the sea

C. Japan will first build floating cities

D. earth's land is in danger

题型:选择题

下列哪项不是深静脉插管引起感染的原因

A.插管时无菌操作不严格

B.经常经导管输注药物

C.营养液配制后低温环境保存超过24小时才经插管输注

D.插管后局部处理不妥

E.营养液配制过程在普通治疗室进行

题型:选择题

下面哪一项不属于DBS3900基站的监控系统()。

A、EMUA

B、PMU(APM30)

C、IBBS

D、DCDU-03

题型:选择题

全面检验是指压力容器停机时的检验,其检验周期分为:安全状况等级为1,2级的,一般每8年至少一次;安全状况等级为3级的,一般2~4年一次;安全状况等级为4级的,其检验周期可由使用单位自行确定。()

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