Setting values for Smax1 and Smax2 under different combinations of iPsi1 and iPsi2 in the two-kinetic sites model

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ZhangZ
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Setting values for Smax1 and Smax2 under different combinations of iPsi1 and iPsi2 in the two-kinetic sites model

Post by ZhangZ » Thu Sep 07, 2023 11:30 pm

Dear Jirka,
Based on my reading of the previous posts in the forum, I have two questions about setting values for Smax1 and Smax2 under different combinations of iPsi1 and iPsi2 in the two-kinetic sites model. I think this involved the setting in the codes. Hope you can answer that.

Because in my applications, I tested different situations as follows,
Model 1: when iPsi1=4 and iPsi2=1, then Smax1=Beta and Smax2=Smax.
Model 2: when iPsi1=5 and iPsi2=0, then Smax1=Beta and Smax2=Smax.
Model 3: when iPsi1=4 and iPsi2=0, then Smax1=Beta and Smax2=0.
Model 4: when iPsi1=1 and iPsi2=0, then Smax1=0 and Smax2=Smax.
Model 5: when iPsi1=0 and iPsi2=0, then Smax1=0 and Smax2=0.


My two questions are as follows,
(1) When iPsi1=4 and iPsi2=1, then Smax1=Beta and Smax2=Smax. This is correct according to the previous posts.
But if iPsi1=1 and iPsi2=4, what will be the values of Smax1 and Smax2?
I think the conclusion can also be applied to my listed Models 2 and 3.

(2) In one post (https://www.pc-progress.com/forum/viewt ... ite#p10309), you answered as “When iPsi1=5 and iPsi2=1 (as in Grazia's examples), site 1 both time-dependent (Smax=Smax2) and depth-dependent (beta=Smax1) blocking, site 2 will be time-dependent blocking (Smax2).”

As for my understanding, due to the limitation of the codes, both Site 1 and Site 2 share the same function of time-dependent blocking (Smax2=Smax). Right?

But in another post (https://www.pc-progress.com/forum/viewt ... ite#p13624), you answered as “If you use iPsi1=5, i.e., you have both Langmuirian and depth blocking on Sites1, you cannot have any blocking on Sites2.”

These two previous answers seem contradictory.


Thanks,
Zengyu
Last edited by ZhangZ on Sun Sep 10, 2023 2:43 am, edited 1 time in total.

Jirka
Posts: 6244
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Re: Setting values for Smax1 and Smax2 under different combinations of iPsi1 and iPsi2 in the two-kinetic sites model

Post by Jirka » Fri Sep 08, 2023 2:10 am

Ad 1.
Model 1: when iPsi1=4 and iPsi2=1, then Smax1=Beta and Smax2=Smax.
when iPsi1=1 and iPsi2=4, then Smax1=Smax and Smax2= Beta.

Ad 2.
Model 2: when iPsi1=5, then Smax1=Beta and Smax2=Smax.
When you use iPsi1=5, Smax2 is used for Smax in the first blocking function. Then you should either not use the second attachment at all, and if you use it, then its blocking function will automatically be set to iPsi2= 1, since Smax2 is nonzero, and will be used as Smax in the second function as well.

J.

ZhangZ
Posts: 3
Joined: Fri Aug 04, 2023 7:48 am
Location: China

Re: Setting values for Smax1 and Smax2 under different combinations of iPsi1 and iPsi2 in the two-kinetic sites model

Post by ZhangZ » Fri Sep 08, 2023 6:28 am

Jirka wrote:
Fri Sep 08, 2023 2:10 am
Ad 1.
Model 1: when iPsi1=4 and iPsi2=1, then Smax1=Beta and Smax2=Smax.
when iPsi1=1 and iPsi2=4, then Smax1=Smax and Smax2= Beta.

Ad 2.
Model 2: when iPsi1=5, then Smax1=Beta and Smax2=Smax.
When you use iPsi1=5, Smax2 is used for Smax in the first blocking function. Then you should either not use the second attachment at all, and if you use it, then its blocking function will automatically be set to iPsi2= 1, since Smax2 is nonzero, and will be used as Smax in the second function as well.

J.

Dear Jirka,
Thanks for your quick and concise reply.
Following your Answer 1, I have a further question. If I reverse the setting in Model 2, will the following be correct?

When iPsi1=0 and iPsi2=5, then Smax1=Smax and Smax2=Beta.
When iPsi1=1 and iPsi2=5, then Smax1=Smax and Smax2=Beta.


Thank you,
Zengyu

Jirka
Posts: 6244
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Re: Setting values for Smax1 and Smax2 under different combinations of iPsi1 and iPsi2 in the two-kinetic sites model

Post by Jirka » Fri Sep 08, 2023 5:40 pm

I should note that HYDRUS is not meant to support the iPsi=5 model (see the technical manual and help).

Anyway, you cannot assign this model to the second attachment sites. There, it is not supported at all.
J.

ZhangZ
Posts: 3
Joined: Fri Aug 04, 2023 7:48 am
Location: China

Re: Setting values for Smax1 and Smax2 under different combinations of iPsi1 and iPsi2 in the two-kinetic sites model

Post by ZhangZ » Sun Sep 10, 2023 11:38 pm

Jirka wrote:
Fri Sep 08, 2023 5:40 pm
I should note that HYDRUS is not meant to support the iPsi=5 model (see the technical manual and help).

Anyway, you cannot assign this model to the second attachment sites. There, it is not supported at all.
J.
Dear Jirka,
Thank you very much. I understand clearly now.

Zengyu

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