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$$
  \frac{\mathrm{d}^2 \mathbf{r}_i}{\mathrm{d} t^2}=
  \frac{\mathrm{d} \mathbf{v}_i}{\mathrm{d} t}
  =\mathbf{F}_{i}=\sum_{i\neq j}(\mathbf{F}_{ij}^{C}+\mathbf{F}_{ij}^{D}+\mathbf{F}_{ij}^{R}),
$$

$$
  C_v\frac{\mathrm{d} T_i}{\mathrm{d} t}= q_{i} = \sum_{i\neq j}(q_{ij}^{C}+q_{ij}^{V}+q_{ij}^{R}),
$$

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