题干

 涂在手上的酒精比涂在手上的水干得快,壶中的水比壶中的食用油干得快…小明猜想:液体蒸发的快慢可能与液体的种类有关.

(1)为此,小明用一根两端开口的直玻璃管、塑料板、电子手表、笔、温度相同的水、大豆油和酒精设计了如下实验方案:

A.在玻璃管上端附近化一标记线,并将下端竖直插入水中,直到管内水面到达标记线

B.用手指堵住玻璃管上端管口,将玻璃管从水中取出

C.将玻璃管移到塑料板上方,放开手指,让水滴滴在塑料板上并开始计时,

D.用同样的方法先后取出大豆油和酒精滴在塑料板上并计时;

E.记录液滴变干所用的时间t,得出结论.

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同类题2

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    人愉快时面呈笑容,哀痛时放出悲声,这种内心情感也能在中国书法里表现出来,别的民族写字还没有能达到这种境地的。唐代韩愈说张旭善草书,“有动于心,必于草书焉发之”,“观于物,见……天地事物之变,可喜可愕,一寓于书”。张旭的书法不但抒写自己的情感,也表现出自然界各种变动的形象,但这些形象是通过他的情感所体会的,因而能形成情景交融的意境。

    汉字的起始是象形的,书法家可以用字的结构来表达物象的结构和生气勃勃的动作,使写的字成为一种表现生命的艺术。元代赵子昂写“子”字时,先习画鸟飞之形,从中吸取对生命形象的构思,使“子”字有着鸟飞形象的暗示,成为一个表现生命的单位。书法家要想使字表现生命,就要用他所具有的方法和工具在字里表现出生命体的骨、筋、肉、血的感觉来。许慎说:“书者,如也。”书的任务是如,写出来的字要“如”我们心中对于物象的把握和理解。但这里并不是完全像绘画那样直接模示客观形体,而是通过较抽象的点、线、笔画来表现的。

    中国人写的字,能够成为艺术品,使用毛笔是另一个重要原因。毛笔铺毫抽锋,极富弹性,所以巨细收纵,变化无穷,这是欧洲人用管笔、钢笔、铅笔及油画笔所不能比的。正是这个特殊的工具使中国人的书法有可能成为一种世界独特的艺术。中国书法用笔有中锋、侧锋,方笔、圆笔,轻重、疾徐等各种区别,皆是运用单纯的点画而成其变化,来表现丰富的内心情感和世界诸形相;就像音乐运用少数的乐音,依据和声、节奏与旋律的规律,构成千万乐曲一样。唐朝张彦远在《历代名画记》里说张芝学习草书之法,“一笔而成,气脉通连,隔行不断”。石涛《画语录》也说,“人能以一画具体而微,意明笔透”,“一画之法立而万物著矣”。但这里所说的一笔、一画,并不真是一条不断的线纹,而是如郭若虚所言,“自始及终,连绵相属,气脉不断”。中国书画家正是运用这一笔的点画,构成万千的艺术形象,创造中国特有的书画艺术。

    中国书法从一笔入手,但一笔不能摄万象,须要变动而成八法,才能尽笔画的“势”,以反映物象里的“势”。这“永字八法”由“永”字的笔画而来,为侧(点)、勒(横)、努(直竖)、超(钩)、策(提)、掠(长撇)、啄(短撇)、磔(捺)。这些笔画,悬腕中锋,运全身之力以赴之,笔迹落纸,反映着生命的运动,显示着力量。点,不称点而称为侧,是说它的“势”,左顾右瞰,欹侧不平。卫夫人说“点如高峰坠石,磕磕然实如崩也",一点之力真是石破天惊。横画称为“勒”,是说它的势,牵缰勒马,跃然纸上。书法的“美”就是势、是力、是虎虎有生气的节奏,它倾向于壮美。

    字由点画连贯穿插而成,点画的空白处也是字的组成部分,和笔画具同等的艺术价值。所以大书法家邓石如曾说书法要“计白当黑”,无笔墨处也是妙境!虚实相生,才完成一个艺术品。中国书法艺术里这种空间美,在篆、隶、真、草、飞白里有不同的表现,尚待我们钻研。

(摘编自宗白华《中国书法里的美学思想》)

同类题3

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    It's rare that you see the words “shyness” and “leader” in the same sentence. After all, the common viewpoint is that those outgoing and sociable guys make great public speakers and excellent networkers and that those shy people are not. A survey conducted by USA Today referred to 65 percent of executives who believed shyness to be a barrier to leadership. Interestingly, the same article stresses that roughly 40 percent of leaders actually are quite shy—they're just better at adapting themselves to situational demands. Bill Gates, Warren Buffet and Charles Schwab are just a few “innies”.

    Unlike their outgoing counterparts who are more sensitive to rewards and risk-taking, shy people take a cautious approach to chance. Rather than the flashy chit-chat that defines social gathering, shy people listen attentively to what others say and absorb it before they speak. They're not thinking about what to say while the other person is still talking, but rather listening so they can learn what to say. Along the same lines, shy people share a common love of learning. They are intrinsically (内在地) motivated and therefore seek content regardless of achieving an outside standard.

    Being shy can also bring other benefits. Remember being in school and hearing the same kids contribute, until shy little Johnny, who almost never said a word, cut in? Then what happened? Everyone turned around to look with great respect at little Johnny actually talking. This is how shy people made good use of their power of presence: they “own” the moment by speaking calmly and purposefully, which translate to a positive image.

    Shyness is often related to modesty. Not to say that limelight-seekers aren't modest, but shy people tend to have an accurate sense of their abilities and achievements. As a result, they are able to acknowledge mistakes, imperfections, knowledge gaps and limitations.  Since shy people have a lower sensitivity to outside rewards than outgoing ones, they're more comfortable working with little information and sticking to their inner desires. Shy people are also more likely to insist on finding solutions that aren't primarily apparent. Don't believe me? Maybe you'll believe Albert Einstein, who once said, “It's not that I'm so smart, it's that I stay with problems longer.” Obviously, finding certainty where uncertainty is typically popular is a huge plus for any successful person.

    The myth that shy people are less effective leaders than their outgoing fellows is just a misunderstanding. Make wise use of your personality strengths to lead your business no matter what side of the range you fall on.