Copolymers mPEG-PCL were prepared and grafted onto polyethylenimine (PEI) to synthesize copolymers mPEG-PCL-g-PEI with low cytotoxicity. The mPEG-PCL-g-PEI coul
The eigenvalue problems of the buckling loads and natural frequencies of a braced beam on an elastic foundation are investigated.The exact solutions for the eig