begin{table}
    caption{Transitions between different powder groups}
    label{tab:transition}
    centering
    rule{textwidth}{heavyrulewidth}
    vspace{-baselineskip}
    begin{subequations}
    begin{flalign}
    &textbf{Transition}
    &textbf{Equation}
    nonumber
    &&\
    hline
    &textbf{C/A}
    & log(d_p) &= 4.014 - 0.725 log( rho_s - rho_g)       label{eq:transitionCA}
    && text{cite{B1992A}}\
    &textbf{A/B}
    &log(d_p) &= 5.958 - 1.17 log( rho_s - rho_g) label{eq:transitionAB}
    &&\
    &textbf{B/D}
    &
    log(d_p) &= 5.425 - 0.807 log( rho_s - rho_g) label{eq:transitionBD}
    &&
    end{flalign}
    end{subequations}
    rule{textwidth}{heavyrulewidth}
    end{table}

documentclass{article}
usepackage{amsmath}
usepackage{booktabs, tabularx}
newcolumntype{N}{>{refstepcounter{equation}(theequation)}r}

usepackage{lipsum}

begin{document}
    begin{table}
    caption{Transitions between different powder groups}
    label{tab:transition}
    centering
begin{subequations}
    begin{tabularx}{linewidth}{>{bfseries}c
                                 >{raggedlefthsize=0.7hsize $}X<{=$}@{}
                                 >{hsize=1.3hsize $;}X<{$}
                                 N @{;}l}
    toprule
Transition  &   multicolumn{2}{c}{textbf{Equation}} &   multicolumn{2}{c}{}                  \
    midrule
C/A & log(d_p) & 4.014 - 0.725 log(rho_s - rho_g) & label{eq:transitionCA} & cite{B1992A} \
A/B & log(d_p) & 5.958 - 1.17  log(rho_s - rho_g) & label{eq:transitionAB} & cite{B1992A} \
B/D & log(d_p) & 5.425 - 0.807 log(rho_s - rho_g) & label{eq:transitionBD} & cite{B1992A} \
    bottomrule
    end{tabularx}
end{subequations}
    vskip-baselineskip
    end{table}
see equations eqref{eq:transitionCA}, eqref{eq:transitionAB} and eqref{eq:transitionBD}.
lipsum*[11]
end{document}