“铁丝在氧气中燃烧”实验现象之一是“火星四射”其成因是铁丝不纯,混有与金刚石组成

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问题:

“铁丝在氧气中燃烧”实验现象之一是“火星四射”其成因是铁丝不纯,混有与金刚石组成元素相同的一种单质,燃烧时,在熔化的物质内形成很多气泡,气泡炸裂时引起“火星四射”。请写出不纯铁丝在纯氧中燃烧发生的两个化学方程式:_____________________、_____________________。

考点:化学反应方程式的书写
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在距地面足够高的O1点以水平速度v0抛出小球A,经过一段时间,在O1正下方的某点O2又以速度2v0与小球A同向抛出另一小球B,A恰好在空中的M点被B球击中,已知O1M与水平方向的夹角为45°,重力加速度为g。求O1、O2两点之间的高度差。

题型:填空题

. ---_______ skirt do you like best?   

--- The blue one.[ ]

A. Whose  

B. What colour    

C. Which      

D. who's

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在“俗民既不能生生而务”中,“生生”之义为()

A.生养生命

B.使生命生长

C.珍惜生命

D.使生命存活

题型:填空题

For many people today, reading is no longer relaxation. To keep up their work they must read letters, reports, trade publications, interoffice communications, not to mention newspapers and magazines: a never ending flood of words. In (1) a job or advancing in one, the ability to read and comprehend (2) can mean the difference between success and failure. Yet the unfortunate fact is that most of us are (3) readers. Most of us develop poor reading (4) at an early age, and never get over them. The main deficiency (5) in the actual stuff of language itself—words. Taken individually, words have (6) meaning until they are strung together into phrases, sentences and paragraphs. (7) , however, the untrained reader does not read groups of words. He laboriously reads one word at a time, often regressing to (8) words or passages. Regression, the tendency to look back over (9) you have just read, is a common bad habit in reading. Another habit which (10) down the speed of reading is vocalization—sounding each word either orally or mentally as (11) reads.
To overcome these bad habits, some reading clinics use a device called an (12) , which moves a bar(or curtain) down the page at a predetermined speed. The bar is set at a slightly faster rate (13) the reader finds comfortable, in order to "stretch" him. The accelerator forces the reader to read fast, (14) word by word reading, regression and subvocalization practically impossible. At first (15) is sacrificed for speed. But when you learn to read ideas and concepts, you will not only read faster, (16) your comprehension will improve. Many people have found (17) reading skill drastically improved after some training. (18) Charlie Au, a business manager, for instance. His reading rate was a reasonably good 172words a minute (19) the training; now it is an excellent 1,378 words a minute. He is delighted that how he can (20) a lot more reading material in a short period of time.

A.lies
B.combines
C.touches
D.involves

题型:填空题

阳水()

A.肿多由上而下,继及全身

B.病性为虚中夹实,以虚为主

C.水肿按之陷下不起,甚至按之如泥

D.单纯治以通腑

E.不必节制房事

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