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论述抗日战争三阶段概况,中国战场的作用和贡献,以及抗战胜利的原因和意义。

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临床上描述的组织受照量是指:()

A. 照射量
B. 吸收剂量
C. 百分深度剂量
D. 射线能量

一·二八事变,(福建事变,皖南事变)

下面的短文有15处空白,请根据短文内容为每处空白白确定1个最佳选项。 It sounds all wrong-drilling holes in a piece of wood to make it more resistant to knock. But it works because the energy from the blow gets distributed throughout the wood rather than focusing on one weak spot. The discovery should lead to more effective and lighter packaging materials. Carpenters have known (51) centuries that some woods are tougher than others. Hickory(山核桃木), for example, was turned into axe handles and cartwheel spokes (车轮辐条) because it can absorb shocks without breaking. White oak (橡木), for example, is much more easily damaged, (52) it is almost as dense. Julian Vincent at Bathe University and his team were convinced the wood’s internal structure could explain the differences. Many trees have tubular(管状的) vessels that run (53) the trunk and carry water to the leaves. In oak they are large, and arranged in narrow bands, but in hickory they are smaller, and more evenly distributed. The researchers (54) this layout might distribute a blow’s energy throughout the wood, soaking up a bigger hit. To test the idea, they drilled holes 0.65 millimeters across into a block of spruce(云杉), a wood with (55) vessels, and found that (56) withstood a harder knock. (57) when there were more than about 30 holes per square centimeter did the wood’s performance drop off. A uniform substance doesn’t cope well with knocks because only a small proportion of the material is actually (58) . All the energy from the blow goes towards breaking the material in one or two places, but often the pieces left (59) are pristine(未经破坏的). "But instead of the energy being concentrated in one place, the holes provide many weak spots that all absorb energy as they break", says Vincent, "You are controlling the places (60) the wood breaks, and it can then absorb more (61) , more safely". The researchers believe the principle could be applied to any material- (62) example, to manufacture lighter and more protective packaging. That could (63) be used in car bumpers (保险杠), crash barriers and armor for military vehicles, says Ulrike Wegst, (64) the Max Plank Institute for Mental Research in Stuttgart. But she emphasizes that you’d (65) to design the substance with the direction of force in mind. "The direction of loading is crucial", she says.

A. effected
B. beaten
C. slapped
D. affected

阅读下列材料 材料一: 没收一切私人的或团体的——豪绅、地主、祠堂、庙宇、会社、富农——田地、山林、池塘、房屋,归苏维埃政府公有,分配给无地、少地的农民及其他需要的贫农使用。 ——引自中共1930年《苏维埃土地法》 材料二: 1931年2月,毛泽东按中央决定指示各级政府发一布告:“说明过去分好了的田,(实行抽多补少,抽肥补瘦),即算分定,得田的人,即由他管所分得的田,这田由他私有,别人不得侵犯。…‘租借买卖,由他自主;田中生产,除交土地税于政府外,均归农民所有。”——转引自胡绳主编《中国共产党的七十年》 材料三: 一方面要规定地主应该普遍地减租减息,不得抗不实行。另一方面,又要规定农民有交租交息的义务.不得抗不交纳。——引自中共中央1942年《关于抗日根据地土地问题》 材料四: 一切地主的土地及公地,由乡村农会接收,连同乡村其他一切土地,按乡村全部人口,不分男女老幼,统一平均分配……并归个人所有……承认其自由经营、买卖及在特定条件下出租的权利。 ——引自1947年《中国土地法大纲》 请回答: 材料四与材料一、二之间有什么联系说明了什么

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