APS夹紧装置的驱动方式为()。A.液压推动式 B.电动式 C.气动式

题型:单项选择题

问题:

APS夹紧装置的驱动方式为()。

A.液压推动式

B.电动式

C.气动式

考点:干法熄焦工干法熄焦工题库
题型:单项选择题

《素问,六元正纪大论》:“民病寒热”。王冰注:“寒热,虐也。”此条的注释方法是()

A.定义法

B.对释法

C.比较法

D.描述法

题型:单项选择题
根据短文内容,从下框A~F选项中选出能概括每段主题的最佳选项,并在答题卡上将该选项涂黑。选项中有一项为多余项。
A.How do we get the names for the days?
B.The origin of division of the times.
C.How did men invent the week?
D.The Jews names the seven days.
E.How did the Egyptians and the Romans name the days?
F.Reason for no names of the days.
1._____________
Do you know how the days of the week get their names? There was a time in the early history of man when the days had no names! The reason was quite simple:men had not invented the week.
2. _____________
In those days, the only division of times was the month, and there were too many days in the month for each of them to have a separate name. But when men began to build cities, they wanted to have a special day on which to trade, a market day. Sometimes these market days were fixed at every tenth day, sometimes every seventh or every fifth day. The Babylonians decided that it should be every seventh day. On this day they didn't work, but met for trade and religious festivals.
3. _____________
The Jews followed their example, but kept every seventh day for religious purposes. In this way the week came into existence. It was the space between market days. The Jews gave each of the seven days a name, but it was really a number after the Sabbath day(which was Saturday). For example, Wednesday was called the fourth day (four days after Saturday).
4. _____________
When the Egyptians adopted the seven­day week, they named the days after five planets, the sun, and the moon. The Romans used the Egyptian names of their days of the week: the day of the sun, of the moon, of the planet Mars(火星), of Mercury(水星), of Jupiter(木星), of Venus(金星), and of Saturn(土星).
5. _____________
We get our names for the days not from the Romans but from the Anglo­Saxons, who called most of the days after their own gods, which were roughly the same as the gods of the Romans. The day of the sun became Sunnandaeg, or Sunday. The day of the moon was called Monandaeg, or Monday. The day of the Mars became the day of Tiw, who was their god of war. This became Tiwesday, or Tuesday. Instead of Mercury's name, that of the god Woden was given to Wednesday. The Roman day of Jupiter, the thunderer, became the day of the thunder god Thor, and this became Thursday. The next day was named for Frigg, the wife of their god Odin, and so we have Friday. The day of Saturn became Saeterndaeg, a translation from the Roman, the Saturday.
题型:单项选择题

如图所示,用半径为R=0.4m的电动滚轮在长薄铁板上表面压轧一道浅槽,滚轮转动的角速度恒为ω=5rad/s,薄铁板的长为L=2.8m、质量为m=10kg,滚轮与铁板、铁板与工作台面间的动摩擦因数分别为μ1=0.3和μ2=0.1,铁板从一端放入工作台的滚轮下,工作时滚轮对铁板产生恒定的竖直向下的压力,其大小为F=100N,在滚轮的摩擦作用下铁板由静止向前运动并被压轧出一浅槽,g取10m/s2

小题1:通过分析计算,说明铁板将如何运动;

小题2:加工一块铁板需要多少时间;

小题3:加工一块铁板电动机要多消耗多少电能。

题型:单项选择题

根据图一和图二,请回答下列问题。(每空1分 共5分)

①嫁接包括两种方式,图一所指的方式是             ,图二所指的方式是              

②两种嫁接方式的不同在于接穗不同,图一是用          做接穗,图二是用          做接穗。

③嫁接时应当使接穗和砧木的            紧密结合,以确保接穗成活。

题型:单项选择题

人工线(仿真线)就是大容量的电容。

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