让直径比孔穴小的分子通过而将大的分子留在外面,故又称“分子筛”。“分子筛”在表面

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问题:

让直径比孔穴小的分子通过而将大的分子留在外面,故又称“分子筛”。“分子筛”在表面化学中有重要作用,是重要的催化剂和催化剂载体。以高岭土(主要成分:Al2Si2O7·2H2O)、石灰石、海水为原料生产“分子筛”的工艺流程如下:

回答下列问题

(1)操作a的作用是                       ,副产品A是     

(2)气体通入滤液中发生反应的离子方程式为                            

(3)NaOH和不溶物在适当温度下发生的化学反应方程式为                    

                                     

(4)高岭土主要成分的化学式可表示为Al2O3·2SiO2·2H2O,则分子筛的化学式也可表示为          

考点:碳单质及化合物单质硅硅酸盐硅酸(原硅酸)
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上市公司非公开发行证券申请文件须包含发行人最近( )的财务报告和审计报告及最近1期的财务报告。

A.五年
B.三年
C.两年
D.一年

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自然界中的水是通过多种路线实现其循环和相变的,下列各项关于水循环的说法中正确的一项是( )。

A.太阳辐射和重力作用是形成水循环的内因
B.降水、蒸发和径流是水循环过程的三个最主要环节
C.海洋和陆地之间水的往复运动过程,被称为水的小循环
D.地球上有75%水存在于海洋中,其余部分则存在于陆地上、大气和生物体中

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结合材料5~14的内容,针对产能过剩问题,你有什么好的思路或建议请站在政府职能部门工作人员的角度,谈一谈你的观点。 要求:观点明确,合理可行,条理清晰,字数不超过500字。

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Starting with his review of Skinner’s Verbal Behavior, Noam Chomsky had led the psycholinguists who argue that man has developed an innate (天生的) capacity for dealing with the linguistic universals common to all languages. Experience and learning then provide only information about the (1) instances of those universal aspects of language which are needed to communicate with other people within a particular language (2) .

This linguistic approach (3) the view that language is built upon learned associations between words. What is learned is not strings of words per se (本身), but (4) rules that enable a speaker to (5) an infinite variety of novel sentences. (6) single words are learned as concepts: they do not stand in a one-to-one (7) with the particular thing signified, but (8) all members of a general class.

This view of the innate aspect of language learning is at first not readily (9) into existing psychological frameworks and (10) a challenge that has stimulated much thought and new research directions. Chomsky argues that a precondition for language development is the existence of certain principles "intrinsic (原有的) to the mind" that provide invariant structures (11) perceiving, learning and thinking. Language (12) all of these processes; thus its study (13) our theories of knowledge in general.

Basic to this model of language is the notion that a child’s learning of language is a kind of theory (14) . It’s thought to be accomplished (15) explicit instruction, (16) of intelligence level, at an early age when he is not capable of other complex (17) or motor achievements, and with relatively little reliable data to go on. (18) , the child constructs a theory of an ideal language which has broad (19) power. Chomsky argues that all children could not develop the same basic theory (20) it not for the innate existence of properties of mental organization which limit the possible properties of languages.

2()

A.region

B.district

C.vicinity

D.community

题型:填空题

可导致病理性语颤增强的疾病是()

A.阻塞性肺不张

B.大量胸腔积液

C.支气管哮喘发作

D.胸膜增厚粘连

E.肺结核空洞

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