在同晶异质代换作用中，黏土矿物中的Si4+被Al3+取代，晶体中产生了剩余正电荷，使晶层带正电。
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大多数植物都不能在pH值低于3.5和高于9.0的环境下生长。
A. 对
B. 错
土壤保肥供肥能力影响最大的一种吸收方式是生物吸收作用。
A. 对
B. 错
________ got into the room, _________ the telephone rang.
A. He hardly; then
B. Hardly had he; when
C. He had not; than
D. Not had he; when
— I don’t think I can walk any further.— _________.Let’s stop here for a rest.
A. Neither can I
B. Neither do I
C. I didn’t think so
D. I think so
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