中滑板丝杠与()部分由前螺母、螺钉、中滑板、后螺母、丝杠和楔块组成。 A.齿轮 B.

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问题:

中滑板丝杠与()部分由前螺母、螺钉、中滑板、后螺母、丝杠和楔块组成。

A.齿轮

B.挂轮

C.螺母

D.机床

考点:数控车工考试高级数控车工高级数控车工题库
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如图所示,在匀强电场中分布着A、B、C三点,且BC=20cm.当把一个电荷量q=10-5C的正电荷从A点沿AB线移到B点时,电场力做功为零.从B点移到C点时,电场力做功为-

3
×10-3J,则电场的方向为______,场强的大小为______.

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下列试剂的保存不正确的是

A.漂白粉必须密封保存

B.新制的氯水用棕色瓶保存

C.液溴用一层水封盖再密封保存

D.固体碘放在棕色细口瓶中

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Research on animal intelligence always makes me wonder just how smart humans are. (91) the fruitfly experiments described in Carl Zimmer’s piece in the Science Times on Tuesday. Fruit flies who were taught to be smarter than the average fruit fly (92) to live shorter lives. This suggests that (93) bulbs burn longer, that there is an (94) in not being too terrifically bright.
Intelligence, it (95) , is a high-priced option. It takes more upkeep, burns more fuel and is slow (96) the starting line because it depends on learning—a gradual (97) —instead of instinct. Plenty of other species are able to learn, and one of the things they’ve apparently learned is when to (98) .
Is there an adaptive value to (99) intelligence That’s the question behind this new research. I like it. Instead of casting a wistful glance (100) at all the species we’ve left in the dust I.Q. wise, it implicitly asks what the real (101) of our own intelligence might be. This is (102) the mind of every animal I’ve ever met.
Research on animal intelligence also makes me wonder what experiments animals would (103) on humans if they had the chance. Every cat with an owner, (104) , is running a small-scale study in operant conditioning, we believe that (105) animals ran the labs, they would test us to (106) the limits of our patience, our faithfulness, our memory for terrain. They would try to decide what intelligence in humans is really (107) , not merely how much of it there is. (108) , they would hope to study a (109) question. Are humans actually aware of the world they live in (110) the results are inconclusive.

A.deliver

B.carry

C.perform

D.apply

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男,60岁。因胃溃疡合并多次大出血,行胃大部分切除术。

该患者术后5天出现黑便,最可能的原因是()

A.继发性溃疡

B.吻合口出血

C.术后胃内残余血

D.小弯侧关闭止血不确切

E.吻合口部分黏膜坏死脱落

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祛风湿药分几类各类药的主要作用是什么

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