Dimensions:
X - temperature (T) in K
Y - fNO3 (NO3/Anions(aq). fNO3=[NO3-]/Anions(aq) (ueq/ueq); Anions(aq) =  2*SO42- + NO3- + Cl-
Z - RH in 0.6~1
Vgood: X*Y*Z;
	non-ideality correction factor (cni) at corresponding grid

How to use the code: 
(1)choose the version of cni you'd like to get. Availabel versions include:
	ISR_molality: molality-based pH definition, calculated from  ISORROPIA model
	AIM_molality: molality-based pH definition, calculated from  E-AIM IV model
	AIM_activity: activity-based pH definition, calculated from  E-AIM IV model
(2)define the time series of T, RH and fNO3, and then run the code to get cni.

e.g., let:
	ver='ISR_molality';
	T=[271;298];RH=[0.7;0.8];fNO3=[0.3;0.5];
Then run:
	cni=get_cni(ver,T,RH,fNO3)
you should get:
	cni=[0.5026;0.8626];
