BTP-4Cl-12 (CAS number 2447642-41-1), also known as Y7-BO or BO-4Cl, belongs to the highly efficient non-fullerene acceptor Y6 family. The only difference between BTP-4Cl-12 and Y7 is that BTP-4Cl-12 has larger butyloctyl alkyl chains that are attached to the pyrrole rings ...
第五章机械振动 任一物理量在某一定值附近往复变化均称为振动.任一物理量在某一定值附近往复变化均称为振动.振动机械振动物体围绕一固定位置往复运动.物体围绕一固定位置往复运动.运动形式:直线、平面和空间振动.运动形式:直线、平面和空间振动.例如一切发声体、心脏、海浪起伏、例如一切发声体、心脏、海浪起伏、地震...