题干

下列化学方程式中,不能用H++OH=H2O表示的是(   )

A:2NaOH+H2SO4═Na2SO4+2H2O

B:Ba(OH)2+2HCl═BaCl2+2H2O

C:KOH+HCl═KCl+H2O

D:Cu(OH)2+2HNO3═Cu(NO32+2H2O

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D

同类题4

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                                                                                      汉字书写发展为书法艺术的成因

      在我们固有的观念中,汉字与书法艺术是绝对不能割裂的。“书法是书写汉字的艺术”。世界上存在着数百个国家和民族,它们大都有自己的语言和文字,但它们的文字书写没有成为一门艺术。而独有汉字在其衍变过程中成了艺术,或在汉字产生之初便具有某种艺术性。一些学者以“书画同源”说阐释汉字成为艺术的起因及性质,如刘纲纪《书法美学简论》、金学智《书法美学谈》等。由于文字起源于象形,并且由于“文字的点画书写能够造成各种同现实生活中的形体(或动态)有类似之处的形体”(刘纲纪语),所以文字书写成了能够描写现实生活的形象艺术。这种以为书法一定反映现实生活的观念,显然只是套用了一般的艺术原理。更多的人认为汉字成为艺术是由于汉字的结构这一事实,并由此认定书法是一门抽象艺术。汉字结构的繁简、点画的错落造就了许多美的因素,这是其成为艺术的一个先决条件。没有汉字结构的复杂性,其单纯的书写成为艺术似乎是不可想象的。

从“六书”造字原则看,我们似难以确信汉字产生的过程即是书法艺术产生的过程。“六书”即象形、指事、形声、会意、转注、假借。其中象形、指事、形声、会意为造字方法,转注、假借为用字方法。四种造字方法的目的并非在于审美,而均在于实用。即使如象形,是根据物质形状描绘简化而成,其简化的过程多少含有某些抽象的因素,然其目的仍是致用为上。由此可见,汉字在一开始并无明显成为书法艺术的迹象。

我们似应再作如下的假设:如果说,作为书法艺术主要表现工具的毛笔至今仍没有发明,今天所说的书法是否能在历史上作为一种艺术而存在呢?也许人们会说,今天见到的许多历代名作并不全由毛笔表现,那些墓志砖铭、摩崖刻石、甲骨卜辞、青铜铭文等等,或由刀刻,或以模铸,而它们的艺术水平仿佛不在毛笔书法之下。但应当指出,这些非毛笔书写类的书法,在它们制作之前已经汲取了毛笔书法的意味(笔意),人们在刻或铸时潜意识地将笔意考虑在文字的运笔中,大多数碑刻则为毛笔书丹后刻石的,这是毛笔使用后给人们在书写时带来某种审美意义上的超越。比较一下笔画尖细的甲骨卜辞与血肉丰美的青铜器铭文,可以悟得毛笔等书写工具的使用对文字书写成为艺术的促进作用。

由此可以断定,汉字书写成为书法艺术的成因,除了先天的汉字特质外,毛笔等工具的使用是一个重要因素,它是文字书写发展为艺术的催化剂。而使毛笔等工具的功能发挥到极致的,则是中国文化思想的渗入。古代大师们在挥运毛笔时感悟到了某种表达其审美理想的可能,这使文字书写跃过单纯的美而成为一门独立而蕴含极深的艺术。

同类题5

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    When I was a little kid, one of my favorite things to do was going to the zoo. I have recently heard that there are debates as to whether elephants should live in zoos or should they wander around free. My position is that elephants should live in zoos for people to see.

    Many experts say that elephants have a good life living in zoos. There are 78 zoos that exhibit elephants. Most zoos are taking the necessary steps to make living conditions better for the elephants. They are doing things such as replacing hard floors with sand or dirt. This makes it easier for them to wander around. Zoos are also expanding their elephant house to give the large animals more room to go around.

    Zoos also protect endangered species. According to the World Wildlife Fund, in 2014 the total population of African elephants was around 700,000, and the Asian elephant population was around 32,000. The Asian elephants are on a path to dying out. Without zoos, they all are likely to disappear within our lifetime. The National Zoo plans to spend millions of dollars on a new Asian elephant habitat. That way, they can start their own group if the Asian elephants are gone.

    There are people who want zoos to empty all of their elephant displays. If they decide to do so, it would take the chance to see elephants up close away from people. That could change the public's favorable opinion of elephants. National Zoo director John Berry says that allowing visitors to experience the elephants up close encourages people to care about endangered species.  During one of my visits to the zoo, it was a very hot day. I was sweating a lot. Big Ben, the largest elephant on display, walked up to me and gently squirted(喷) my face with water from his trunk. Everyone was amazed at what he did. That was a very nice thing for Big Ben to do. I am sure that elephants are the nicest animals on earth. I wish all zoos would keep their elephant displays open to the public. I want all my friends to be able to experience what I did with Big Ben.

    I feel zoos should follow all the necessary steps to keep elephants in zoos. I would raise money at my school if I thought it would help to keep elephants in zoos.