This paper introduces the structure,preparation and properties of melamine,and analyses the toxicity and harm of melamine to human and animal.

Views of energy is a core concept in middle school chemistry Study.Construction of studentspviews of energy may help them to form the mode of thinking about the motion of electrons, and to understand the methods of thinking about matter and its changes in view of energy. The strategies for teacher to construct studentspviews of energy are proposed:(1)understand particles have heat energy through learning matter is composed of tiny particles,(2)form the mode of thinking about the motion of e-lectrons in view of energy through learning atomic structure,(3)develop understanding of electrons with high energy be not stable through learning elements and compounds,(4)strengthen understanding of mat-ter changes accompanied by energy changes through accumulating the phenomena of chemical reactions,(5)understand matter changes are accompanied by energy changes through learning conception and theory of chemical bond,(6)understand the theory of effective collision through discussion about the conditions affecting reaction rate,(7)further understand conservation of energy through thermochemistry learning,(8) use concept map to help construct views of energy.