[ Eq(Derivative(x1, t), (1*k28*x37*k22 + (-1)*k39*x3*x1*k22 + 1*k64*x23*k22)/k22),
  Eq(Derivative(x2, t), ((-1)*(k46*x23*x2 + (-k47*x37))*k22 + (-1)*(k48*x2*x9 + (-k49*x31))*k22 + 1*Piecewise(((k18 + (-x2))*1/k19, Gt(t, k17)), (0, True))*k22)/k22),
  Eq(Derivative(x3, t), (1*k38*x4*k22 + (-1)*k39*x3*x1*k22)/k22),
  Eq(Derivative(x4, t), (1*k28*x37*k22 + (-1)*k38*x4*k22 + (-1)*(k57*x4*x19 + (-k58*x25))*k22 + 1*k64*x23*k22)/k22),
  Eq(Derivative(x5, t), (1*k31*(x31 + x37)*k22 + (-1)*k59*x5*k22)/k22),
  Eq(Derivative(x6, t), (1*(k36*x7*x24 + (-k37*x6))*k22 + (-1)*k65*x6*k22)/k22),
  Eq(Derivative(x7, t), ((-1)*(k36*x7*x24 + (-k37*x6))*k22 + (-1)*(Piecewise((1000, Gt(t, 1000)), (0, True))*x7*x26 + (-Piecewise((30000, Gt(t, 1000)), (0, True))*x27))*k22 + 1*k65*x6*k22)/k22),
  Eq(Derivative(x8, t), 0),
  Eq(Derivative(x9, t), ((-1)*(k25*x16*x9 + (-k26*x17))*k22 + (-1)*(k34*x9*x10 + (-k35*x23))*k22 + (-1)*(k44*x13*(x37 + x9 + x31) + (-k45*x30))*k22 + (-1)*(k48*x2*x9 + (-k49*x31))*k22 + 1*k64*x23*k22)/k22),
  Eq(Derivative(x10, t), ((-1)*(k29*x10*x31 + (-k30*x37))*k22 + (-1)*(k34*x9*x10 + (-k35*x23))*k22 + 1*k39*x3*x1*k22)/k22),
  Eq(Derivative(x11, t), (1*(k32*x14*x24 + (-k33*x11))*k22 + (-1)*(k50*x11 + (-k51*x12*x13))*k22)/k22),
  Eq(Derivative(x12, t), 1*(k50*x11 + (-k51*x12*x13))*k22/k22),
  Eq(Derivative(x13, t), (1*(k50*x11 + (-k51*x12*x13))*k22 + (-1)*(k52*x13*x20 + (-k53*x21))*k22 + (-1)*(k60*x32*x13 + (-k61*x15))*k22 + 1*k63*x15*k22)/k22),
  Eq(Derivative(x14, t), ((-1)*(k32*x14*x24 + (-k33*x11))*k22 + 1*(k54*x22*x24 + (-k55*x14))*k22)/k22),
  Eq(Derivative(x15, t), (1*(k60*x32*x13 + (-k61*x15))*k22 + (-1)*k63*x15*k22)/k22),
  Eq(Derivative(x16, t), ((-1)*(k25*x16*x9 + (-k26*x17))*k22 + 1*Piecewise(((k14 + (-x16))*1/k15, Gt(t, k13)), (0, True))*k22)/k22),
  Eq(Derivative(x17, t), 1*(k25*x16*x9 + (-k26*x17))*k22/k22),
  Eq(Derivative(x18, t), 0/k22),
  Eq(Derivative(x19, t), ((-1)*(k40*x19*x28 + (-k41*x29))*k22 + (-1)*(k57*x4*x19 + (-k58*x25))*k22)/k22),
  Eq(Derivative(x20, t), (-1)*(k52*x13*x20 + (-k53*x21))*k22/k22),
  Eq(Derivative(x21, t), 1*(k52*x13*x20 + (-k53*x21))*k22/k22),
  Eq(Derivative(x22, t), (-1)*(k54*x22*x24 + (-k55*x14))*k22/k22),
  Eq(Derivative(x23, t), (1*(k34*x9*x10 + (-k35*x23))*k22 + (-1)*(k46*x23*x2 + (-k47*x37))*k22 + (-1)*k64*x23*k22)/k22),
  Eq(Derivative(x24, t), (1*k1*x25*k66*1/(k24 + k66)*k22 + 1*k27*(Piecewise((1, And(Gt(t, k3), Lt(t, k4))), (0, True)) + Piecewise((x18, And(Gt(t, k5), Lt(t, k6))), (0, True)))*x36*k22 + (-1)*(k32*x14*x24 + (-k33*x11))*k22 + (-1)*(k36*x7*x24 + (-k37*x6))*k22 + (-1)*(k54*x22*x24 + (-k55*x14))*k22 + 1*k8*x29*k66*1/(k56 + k66)*k22)/k22),
  Eq(Derivative(x25, t), 1*(k57*x4*x19 + (-k58*x25))*k22/k22),
  Eq(Derivative(x26, t), (-1)*(Piecewise((1000, Gt(t, 1000)), (0, True))*x7*x26 + (-Piecewise((30000, Gt(t, 1000)), (0, True))*x27))*k22/k22),
  Eq(Derivative(x27, t), 1*(Piecewise((1000, Gt(t, 1000)), (0, True))*x7*x26 + (-Piecewise((30000, Gt(t, 1000)), (0, True))*x27))*k22/k22),
  Eq(Derivative(x28, t), (-1)*(k40*x19*x28 + (-k41*x29))*k22/k22),
  Eq(Derivative(x29, t), 1*(k40*x19*x28 + (-k41*x29))*k22/k22),
  Eq(Derivative(x30, t), 1*(k44*x13*(x37 + x9 + x31) + (-k45*x30))*k22/k22),
  Eq(Derivative(x31, t), (1*k28*x37*k22 + (-1)*(k29*x10*x31 + (-k30*x37))*k22 + (-1)*k31*(x31 + x37)*k22 + 1*(k48*x2*x9 + (-k49*x31))*k22 + 1*k59*x5*k22)/k22),
  Eq(Derivative(x32, t), ((-1)*(k60*x32*x13 + (-k61*x15))*k22 + 1*k62*x35*k22)/k22),
  Eq(Derivative(x33, t), ((-1)*(k42*x34*x33 + (-k43*x35))*k22 + 1*k63*x15*k22)/k22),
  Eq(Derivative(x34, t), ((-1)*(k42*x34*x33 + (-k43*x35))*k22 + 1*k62*x35*k22)/k22),
  Eq(Derivative(x35, t), (1*(k42*x34*x33 + (-k43*x35))*k22 + (-1)*k62*x35*k22)/k22),
  Eq(Derivative(x36, t), (-1)*k27*(Piecewise((1, And(Gt(t, k3), Lt(t, k4))), (0, True)) + Piecewise((x18, And(Gt(t, k5), Lt(t, k6))), (0, True)))*x36*k22/k22),
  Eq(Derivative(x37, t), ((-1)*k28*x37*k22 + 1*(k29*x10*x31 + (-k30*x37))*k22 + 1*(k46*x23*x2 + (-k47*x37))*k22)/k22) ]