【简答题】某制糖厂以甘蔗为原料制糖,同时得到大量的甘蔗渣,对甘蔗渣进行综合利用,不仅可以提高经济效益,而且还能防止环境污染。此厂对产生的大量甘蔗渣按下图所示转化进行综合利用。其中B是A水解的最终产物;C的化学式为C 3 H 6 O 3 ,一定条件下2个C分子间脱去2个水分子可生成一种六元环状化合物;D可使溴水褪色;H的三聚合物I也是一种六元环状化合物。(图中部分反应条件及产物没有列出) (1)写出下列物质的...
【简答题】According to the passage, what do the enclosures of the 17th and 18th centuries mean?
【单选题】What is becoming essential in the course of economic globalization according to the author?
A.
Hiring qualified technical and management personnel.
B.
Increasing understanding of people of other cultures.
C.
Constantly updating knowledge and equipment.
D.
Expanding domestic and international markets.
【判断题】塑料中加入填充剂(又称填料)的目的仅仅是为了降低成本。
【简答题】(10分)分子中只含有2个碳原子的某烃A是其同系物中含碳量最高的物质; 1mol A与1mol HCl加成可得到B;1mol A与1mol H2加成可得到C,并能继续发生如下列图表所示的转变: 据此回答下列问题 (1)写出实验室制取A的反应方程式 ___ _ ____________ ___ ____ ; (2)以B为原料经过加聚反应所得的合成树脂的结构简式为_ _ ___...
【单选题】According to the 4th paragraph, what interests the author is that some politicians fail to ______.
A.
perceive the value of humor.
B.
gain a correct sense of values.
C.
distinguish comedy from tragedy.
D.
realize dangers of hypocrisy.
【单选题】What was the population of London at the beginning of the 19th century according to the conversation?
B.
More than eight million.
C.
Less than eight million.