LED常规光电参数有哪些？
参考答案：
LED常规光电参数有：正向电压，反向电流，发光强度，色温，光通量，发光角度，亮度，照度，光效峰值波长，主波长等
For a moment nothing happened Then _____ all shouting together.
A．voices had come
B．came voices
C．voices would come
D．did voices come
症见头痛而胀，甚则头痛如裂，发热恶风，口渴欲饮，面红目赤，便秘溲黄，舌红苔黄，脉浮数，首选方为
A．川芎茶调散
B．羌活胜湿汤
C．芎芷石膏汤
D．天麻钩藤汤
E．桑菊饮
