But constructionism itself, it also has some defects, the curriculum implementer should know this clearly.同时,建构主义自身也有不足之处, 课程的实施者对此要有清醒的认识.Characteristic defects are of two main types; regression and syneresis.特征缺陷主要有两类:...
The functionalization principle and processing methods of PVC functional materials were introduced.介绍了PVC功能材料的功能化原理和加工方法.Methods: The medicine materials is decoction distill and concentrate with liquid.方法: 药材共水煎煮提取、浓缩,制成...
But, of the vertebrates, unpredictable Nature selected only snakes ( and one lizard ).但是, 在脊椎动物中, 神秘莫测的大自然只选择了蛇 ( 和一种蜥蜴 ).Environmental hormone is a kind of external chemical substance which incretion of human beings and...