Free rider psychology

(free-)radical copolymerization

(Pb)lead-free

．OH free radical

“free lunch” policy

·OH free radical

100m free style

1150mm free standing last-stage steel blades

18 Ni Co-free maraging steel

18Ni Co-free maraging steel

1-Diphenyl-2-picrylhydrazyl DPPH free radical

2-D free shear turbulent flows

2-torsion-free

3D Element-free Galerkin Method

3-D element-free Galerkin method (EFGM)

3-D free curved surface

3-D free shear layer

3D free surface

3D NC Manufacture for Free-form Surface

3-free