In[]:=
kli=30;k2i=0.3;kT=4;d=8.7;n=30;d=2;K=2;
​
In[]:=
k1=(k1i)Exp[-a*F[t]/(kT)];
In[]:=
k2=(k2i)Exp[(1-a)*F[t]/(kT)];
In[]:=
ode1={A'[t]==-(k1)A[t]+(n-A[t])(k2)}
Out[]=

′
A
[t]0.3
1
4
(1-a)F[t]

(30-A[t])-30
-
1
4
aF[t]

A[t]
In[]:=
ode2={F'[t]==(A[t]k1-(n-A[t])k2)d*K}
Out[]=

′
F
[t]4-0.3
1
4
(1-a)F[t]

(30-A[t])+30
-
1
4
aF[t]

A[t]
​
In[]:=
sol=ParametricNDSolve[{ode1,ode2,A[0]==15,F[0]==3},{F[t],A[t]},{t,0,0.1},{a}]
Out[]=
F[t]ParametricFunction
Expression: F[t]
Parameters: {a}
,A[t]ParametricFunction
Expression: A[t]
Parameters: {a}

In[]:=
Manipulate[ParametricPlot[Evaluate[{A[a][t],F[a][t]}/.sol],{t,0,0.1}],{a,0,10}]
Out[]=
​
a
-1.0
-0.5
0.5
1.0
-1.0
-0.5
0.5
1.0