concave GRE

A concave mirror would project a real inverted image of the silverpoint onto the panel, which van Eyck would trace.

镜把颠倒实像投射到木板，于是范艾克便可以在板画。

Dicyano 9,10 dihydro 9,10 ethenoanthracene(4) was synthesized by addition reation of acetylenedinitrile and anthracene. Concave tetrazaporphyrin has been obtained from the four molecules of 4.

乙炔二氰与蒽环加成反应合成了11,12-二氰-9,10-二氢-9,10-亚乙烯基蒽(4),4分4自身加成聚合制备了一种全新型四氮杂口卜啉结构化合物。

As a practical example, an astigmation corrected scanning flat holographio concave grating (SFHCG) is designed and some results of the numerical and optical experiments are given.

给出一消像散SFHCG设计实例和用这块光栅所做实验结果。