{ diff(x1, t) = ((-1)*x5*x1^2/(x1^2 + k6^2) + 1*(1 - k18)*(k7 + (1 - x3)*k1*x2^2/(x2^2 + k9^2)*x1^2/(x1^2 + k13^2))*x9 + 1*x6*(k10 + k11^8/(x9^8 + k11^8)) + (-1)*x4*x1^2/(x1^2 + k14^2) + (-1)*k21*x1^4/(x1^4 + k19^4) + 1*k20*x8/(x8 + 1/100))/k23,
  diff(x2, t) = (1*k8*x1 + (-1)*k3*x2)/k23,
  diff(x3, t) = (1*k4*x1^4/(x1^4 + k16^4)*(1 - x3) + (-1)*k5*x3)/k23,
  diff(x4, t) = (1*k22*k17*k15*x1^4/((k22 - 1)*(1/20)^4 + x1^4) + (-1)*x4*k17)/k23,
  diff(x5, t) = (1*1/k22*k2*k17*((k22 - 1)*2^4 + x9^4)/x9^4 + (-1)*x5*k17)/k23,
  diff(x6, t) = (1*1/(k22*k22)*k12*k17*((k22 - 1)*2^2 + x9^2)/x9^2*((k22 - 1)*(1/20)^2 + x1^2)/x1^2 + (-1)*x6*k17)/k23,
  diff(x7, t) = 0/k24,
  diff(x8, t) = (1*k21*x1^4/(x1^4 + k19^4) + 1*k18*(k7 + (1 - x3)*k1*x2^2/(x2^2 + k9^2)*x1^2/(x1^2 + k13^2))*x9 + (-1)*k20*x8/(x8 + 1/100))/k25,
  diff(x9, t) = (1*x5*x1^2/(x1^2 + k6^2) + (-1)*(1 - k18)*(k7 + (1 - x3)*k1*x2^2/(x2^2 + k9^2)*x1^2/(x1^2 + k13^2))*x9 + (-1)*k18*(k7 + (1 - x3)*k1*x2^2/(x2^2 + k9^2)*x1^2/(x1^2 + k13^2))*x9)/k26 }