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Michael P

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  • Birthday 02/21/1980

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  1. Hi, Thanks for you taking a look. I have a dataset that I'd like to really crank down on for mineral saturation indices. But when I highlight several samples in GSS and run SpecE8, none of them converge. With the resultant SpecE8 window that opens I can change/fiddle with Al3+ by setting it to kaolinite mineral phase at a nominal concentration (saw you do that in a youtube video). This actually works to produce a 'converging' result and I see the suite of minerals and their respeicve SI. 1) I don't know that it is ideal to force Al to a certain mineral phase. These are pore waters from forested volcanic soils, but still... 2) I only see how to make this change in the SINGLE SAMPLE that pops up in SPecE8. There does not seem to be a pre-emptive handling of this Al-preference before the launch from GSS. And so by this 'method' I would have to change/fiddle with Al for each of my 300+ samples. 3) Is there another culprit that might be a better solution to my non-convergence? I would attach a pic of my GSS line headers... to see if you would omit or change anything. Thank you!
  2. Hello, Is there any indication of which database was drawn from when looking at an output file? Thanks! Michael
  3. Thank you Brian. Log K's are unavailable, but definitely good to know adding one will help with balancing. Best, Michael
  4. Also, You asked if I could load it into other programs. The answer is no- not within GSS, where I've worked extensively with SpecE8 in the past. Thank you.
  5. Brian, Thanks for the quick reply! Release 10.0.2 (Build 6257) 32-bit This forum says 'You aren't permitted to upload this kind of file'. It's a .tdat file... Please advise. Thanks, Michael
  6. Hi Brian, Thanks for your reply. However, after reading it and the suggested post about loading the proper dataset, it still is not showing up. Here is what I just did: 1) Closed all instances/programs of GWB. 2) Opened the thermo database editor and confirmed a- my added basaltic glass was there (yes), and b- that the mineral count says 635 not 634 of the previous iteration (yes) 3) Closed the thermo editor 4) Opened RXN 5) File >>open>>thermo data... --> chose the one I just confirmed to be correct in step#2, but when I do, the temporary dialogue box says 634 minerals and so, my basalt is not on the list of minerals So I don't think it's a operating system preferences thing, since it's clear by going to the saved dataset that the database amendment 'sticks'. And yes, thank you, I do save under an obviously edited name to know which one I'm using, and to not mess up the default dataset. Any additional thoughts on loading my dataset into RXN and having it use the one that is clearly showing as correct on the thermo-editor side? Thank you, Michael
  7. Hello, I'm trying to add to the thermo.dat database a basaltic glass so that I might balance its dissolution with CO2 consumption. In the database editor everything seems fine up until I try to 'save.' Save-as works fine, but just using 'save' doesn't proceed- I get some sort of permissions error. Fine- I can save-as once I'm certain of my changes with a new name. It won't even let me save-as then replace an existing name, btw. When in RXN, I chose the new and improved database with my basaltic glass included. (Which I've just checked by opening only the database editor) But the temporary dialogue box clearly shows the mineral count, and it's 1 less than I expect. Lo- when I try to choose the mineral I just added- it isn't there! Have you experienced any permissions issues when saving databases? Or databases not opening properly within RXN? I've tried shutting down the software and even restarting the computer. Still not recognizing my database amendment from inside RXN. Thank you! M
  8. Hello, We are interested in modeling the precipitation (SI values) of birnessite from Mn^2+ that is released to solution by dissolution of primary Mn(II)-bearing silicates. In our system, this Mn(II) reacts with dissolved O2 to form birnessite. However, when we model birnessite precipitation, aqueous species include manganate(VI). The birnessite precipitation reaction in thermo.dat is the disproportionation reaction: Mn8O19H10 + 4H+ = 5Mn^2+ + 3MnO4^2- + 7H2O Therefore, we are wondering if there is another way to model the precipitation of birnessite from Mn2+ solutions that do not require the disproportionation reaction. Or is there another way to otherwise suppress the unlikely manganate(VI) aqueous species for our system. No doubt a new equation would require a new set of LogK values... [e.g, Mn7O13(5H2O which balances using only Mn^2+, H+, and H20 might be a better fit for our system] Pyrolusite (another Mn-oxide) also has a similar disproportionation reaction in the database. Further, in our soil solution system, we have a pH range 8-9.5 and Temp 15-35 C so we need Log K values at 0, 25 and 60. I used the van't Hoff approximation to calculate Log K at 60 for birnessite for the default database. Then, for SpecE8 to give birnessite results, we had to peg O2 concentrations at some value (1ppm for instance). In other words: no oxygen GSS entry = no birnessite. Why is that? Thoughts? Thanks in advance for your insight. Michael
  9. Brian, Thanks for the reply. The new interface looks great, and I look forward to using it. I added the old fashioned way a couple months back... As a follow up, I'd like to ask two things: When adding mineral phases to the database, is it critical to then adjust the mineral phase total in the header section for each addition? e.g. 624 to start, 625 for one addition. Is this total something GWB/SpecE8 ignores during operations? On Slide 10 of the tutorial, a box denotes that info located in this section is optional. Is it pointing only to the mineral "type" entry? Or are molar volume and mole weight also optional for a given entry? (In double checking one of my entries, I noticed my m.w. was off by a few hundredths g) Best, Michael
  10. Hello, I'm double checking my database alterations, and I seem to recall a video on Youtube that highlighted the steps really well. Is that video still available? Thanks, Michael
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