“cofactor”的概念、定义、翻译、参考文献-科学参考

cofactor

Mathematics

Let A be the square matrix [a_ij]. The cofactor, A_ij, of the entry a_ij is equal to (−1)^i + j times the determinant of the matrix obtained by deleting the i-th row and j-th column of A. If A is the 3×3 matrix shown, the factor (−1)^i + j has the effect of introducing a + or-sign according to the pattern on the right:

$A = [\begin{matrix} a_{11} & a_{12} & a_{13} \\ a_{21} & a_{22} & a_{23} \\ a_{31} & a_{32} & a_{33} \end{matrix}] [\begin{matrix} + & - & + \\ - & + & - \\ + & - & + \end{matrix}] .$

So, for example,

$A_{12} = - | \begin{matrix} a_{21} & a_{23} \\ a_{31} & a_{33} \end{matrix} |, A_{31} = + | \begin{matrix} a_{12} & a_{13} \\ a_{22} & a_{23} \end{matrix} | .$

See adjoint (of a matrix)

Statistics

See matrix.

Chemistry

A nonprotein component essential for the normal catalytic activity of an enzyme. Cofactors may be organic molecules (coenzymes) or inorganic ions. They may activate the enzyme by altering its shape or they may actually participate in the chemical reaction.

Biology

A nonprotein component essential for the normal catalytic activity of an enzyme. Cofactors may be organic molecules (coenzymes) or inorganic ions. They may activate the enzyme by altering its shape or they may actually participate in the chemical reaction.

单词	cofactor
释义	cofactor Mathematics Let A be the square matrix [a_ij]. The cofactor, A_ij, of the entry a_ij is equal to (−1)^i + j times the determinant of the matrix obtained by deleting the i-th row and j-th column of A. If A is the 3×3 matrix shown, the factor (−1)^i + j has the effect of introducing a + or-sign according to the pattern on the right: $A = [\begin{matrix} a_{11} & a_{12} & a_{13} \\ a_{21} & a_{22} & a_{23} \\ a_{31} & a_{32} & a_{33} \end{matrix}] [\begin{matrix} + & - & + \\ - & + & - \\ + & - & + \end{matrix}] .$ So, for example, $A_{12} = - \| \begin{matrix} a_{21} & a_{23} \\ a_{31} & a_{33} \end{matrix} \|, A_{31} = + \| \begin{matrix} a_{12} & a_{13} \\ a_{22} & a_{23} \end{matrix} \| .$ See adjoint (of a matrix) Statistics See matrix. Chemistry A nonprotein component essential for the normal catalytic activity of an enzyme. Cofactors may be organic molecules (coenzymes) or inorganic ions. They may activate the enzyme by altering its shape or they may actually participate in the chemical reaction. Biology A nonprotein component essential for the normal catalytic activity of an enzyme. Cofactors may be organic molecules (coenzymes) or inorganic ions. They may activate the enzyme by altering its shape or they may actually participate in the chemical reaction.
随便看	deep-sea geomorphology deep-sea trench deep shaft process deep-sky object Deep Space deep space Deep Space 1 Deep Space Climate Observatory deep-space communications complex deep-space mission system Deep Space Network deep-space network deep-space station deep structure deep/surface structure Deep Thought deep ultraviolet exposure Deep Underground Neutrino Experiment deep weathering deep Web deer Deerparkian de-ethanizer de-extinction de facto/de jure