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问题 问答题 简答题

简述电泳槽不能用自来水的原因。

答案

参考答案：

1、自来水中离子过多，阻碍电泳过程的顺利进行，离子过多造成电导率过大，电流过大，形成电击穿，导致涂膜破裂。

2、若电泳前用自来水洗，则自来水中的其它离子或杂质会附着在磷化膜表面，降低磷化效果。

单项选择题

若水利工程建设项目初步设计静态总投资超过已批准的可行性研究报告估算的静态总投资达15%，则需（）。

A.调整可行性研究估算

B.重新编制可行性研究报告并按原程序报批

C.提出专题分析报告

D.重新编制初步设计
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单项选择题

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.

10（）

A.meets

B.presents

C.offers

D.makes
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