题干

在卢瑟福的α粒子散射实验中,有极少数α粒子发生大角度偏转,其原因是(   )

A:原子的正电荷和绝大部分质量集中在一个很小的核上

B:正电荷在原子中是均匀分布的

C:原子中存在着带负电的电子

D:原子只能处于一系列不连续的能量状态中

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答案(点此获取答案解析)

A

同类题2

阅读材料,完成下列要求。

材料:唐宋之际,乡村自治组织进一步发展,中央政府愈来愈多地借助他们来稳固统治。唐宋推行的科举考试制造了一个拥有特权却居于乡间的士绅阶层。宋代以后,在大举将地方神明纳入国家祀典的同时,随着识字率的激增和文化的相对普及,中央的秩序、教化逐步延伸到基层。吕大钧首创“吕氏乡约”,后由王守仁发扬光大;朱熹等理学家则开始将宗族制度庶民化。迨至明后期,里甲制度崩坏,就由乡约、保甲承担了村落治安职能。清代的里甲、保甲、乡地、宗族、包税人则承担催征赋税的职能,基层自治功能被明清时期勃兴的宗族等各种社会组织分担。

    鸦片战争后,在内乱外患的打击下,农村社会的权力组织趋向解体。进入20世纪,清王朝推行新政,传统的乡里制度、保甲制度被乡镇地方自治所取代。1909年清政府颁行的《城镇乡地方自治章程》列举了乡镇“自治事务”,包括:学务、卫生、道路工事、农工商事务、善举(救贫事业、育婴等)、公共事业、筹集款项等。这既减轻了朝廷负担,又赢得士绅的支持。然而真正重要的国家赋税、行政、司法、警政等核心权力,仍严格把控在朝廷手中,绝对不允许乡镇自治机构插手。晚清时期,士绅通过参与地方自治活动,涉足工商实业、新式教育以及各种文化政治事业,重新设计自我角色,谋求自己的位置。他们中间有许多人开始接受民主思想,开始向资产阶级阵营靠拢。

——摘编自蒋楠《历史视野下的中国乡村治理》等

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同类题3

任务型阅读

    Most of us lead a busy life.____We think, “If I reached my goal, then I would be happy”, or “If I could get a better job, then I would enjoy life.” But why not enjoy life right now?

    Firstly, take time to notice and appreciate the beauty in your own surroundings.____ “There is a great big world of wonder and beauty around us!” And as Brodersen explains, “Look for the beauty of the sunrise and of a friend's smile that brightens your day. Open your eyes to see the beauty you might not normally see. Doing so helps to cheer you up.”

    Secondly, taking time to experience some simple pleasures also can bring joy to your heart and ease your stress. Take me for example.____One universal simple pleasure is finding things that make you laugh. Make time to laugh every day.

    Thirdly, don't take your family and friends for granted. Rich, rewarding relationships add greatly to the enjoyment of life. When you think of someone, why not call, e-mail or write them?____As Wayne Lawton explains, “Invest time in relationships. Remove the attitude, what's in it for me? Happiness is found in putting other's interests, desires and concerns ahead of our own whenever possible. Selfishness is a dead-end street.”____

A. Be aware of beauty in nature.

B. So please treasure relationship.

C. You don't need to travel far to find beauty.

D. Driven by the “urgent”, we forget to enjoy life.

E. In my spare time, I enjoy collecting stamps and reading novels.

F. A short e-mail or phone call can make a world of difference to someone.

G. I delight in simple things like my favorite tea drink, a bubble bath or family photos.