Bone mass density; Elderly people; Osteoporosis.

骨密度；老年人；骨质疏松。

The gravity field out of the earth depends on the interior mass density distribution of the earth.

地球外部重力场是由地球内部物质分布决定的。

The strength of the particles are high, the mass density is increased more apparently compare to other method of granulation.

颗粒强度高，堆积比重的提高较其它造粒方式都更为显著。

Hence, the rest-mass of the neutrino being non-vanishing would influence greatly the mass density and further the evolution of the universe.

因此，中微子是否具有静止质量，将极大地影响着宇宙中的质量密度，从而影响着宇宙演化的进程。

The dynamic mass density can even be negative for the locally resonant sonic materials, as demonstrated both experimentally and theoretically.

实验和理论显示，对于局域共振声学材料而言，动态质量密度甚至还会变成是负的。