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  2. Hi, I have a problem to show all the points in a pH-Eh diagram. I made the GSS file with the chemistry information of the samples (I attached the file). With the Act2 program I made the diagram (Eh vs pH of mercury species), and load the points using Scatter data option (I attached the Act2 file). In the diagram only two samples are graphed in the diagram, and the total of samples are 6. I do not know what is happen. Maybe it is a very easy solution, but I do not see how to show all the samples. Thanks in advance for the support. Regards, AGUA.gss Mercury_REVE.ac2
  3. Great, thank you so much for your help! The model is now running perfectly!
  4. Hello Jia, I cannot believe that there is no way to retrieve the total concentration of all species being formed from a single redox species. But I cannot see any way to get this result in gtplot either. Also in Tedit I don't see product species grouped into their respective oxidation state. In the present (very special) case the total element concentration gives indeed the correct answer. But this doesn't offer a general solution to the problem, e. g. for those cases, where you have two oxidation states of one basis species in comparable concentration. Thank you for the replay anyway. Helge
  5. Hello Alex, I took a quick look at your script and noticed that you have set a really high rate constant for kinetic calcite relative to all the other minerals in your system. To investigate error, I shortened the run time on your simulation to 1 day and looked at mineral dissolution rates during the simulation. Because of the high rate constant for calcite, you have high reaction rates adjacent to zero rates, in a moving front as the model progresses. To see this, plot the x-position on the x-axis and dissolution rate of calcite on the y-axis. Since the rate constant for calcite is many orders of magnitude higher than other minerals, it might be better to consider calcite using the equilibrium approach. If you want to continue using a kinetic rate law for calcite precipitation/dissolution, you should reconsider the rate constant that you are using. I also noticed that you have set a nucleus density for tridymite, kaolinite, and illite. This is only necessary if the mineral you are setting up a kinetic rate law for does not exist in the system. In your case, you do not need them. Hope this helps, Jia Wang
  6. I was wondering if I could get some help with one of my models. I am recreating a soil profile with various minerals and measuring the rate of carbon consumption. The model works and runs perfectly until I add "Kinetic Calcite" into my reactants and then the simulation only gets a minute in before coming up with the message "Newton-Raphson didn't converge after 999 iterations, max residual = 4.27e-07, Xi = 0.0031 / Newton failed at node 0". I was wondering if one of your team could get a better understanding about why I run into this problem. I have attached my input file below. Weathering Soil Test Broken.x1t
  7. Earlier
  8. Hello Helge, If you had decoupled NpO2+ and set it as a basis species entry with no other oxidation states for your model, then you can use the command "report concentration original fluid" to get the total concentration of that component in the fluid. If you are running a redox equilibrium model, where NpO2+ species concentration is calculated, then you would need to retrieve the concentrations of aqueous species with the desired oxidation state (e.g. Np(V)) and sum them in python. Hope this helps, Jia Wang
  9. Hi Polly, I took a quick look at the PhreeqC approach to modeling surface complexation and it seems like the debye lengths input is used in the Donnan approach to calculate the composition of the diffuse layer. GWB does not use the Donnan approach. The program automatically assigns composition to the diffused layer. The surface complexation model ensures that reactions in the surface datasets are honored in the calculation. For any given calculation, you can fix the surface potential in a two layer model in a calculation. If you do that with a surface potential value retrieved from the PhreeqC model, then you might get similar results from both models. Though, I would not recommend doing that as other inputs required between the two models may vary. I would recommend running a full two layer model without setting a constant potential. Best regards, Jia Wang
  10. I am trying to write the log10 total molality of Np(V) to file using python. The present line looks like this: fobj_ResultFile.write(Testcase + '\t' + '1180' + '\t' + 'log10(conc_oxidationstate(NpO2<+>))' + '\t'+ str(math.log10(myGWB.results('concentration "NpO2+"', 'molal')[0])) + '\n') A normal export for a single species looks like this fobj_ResultFile.write(Testcase + '\t' + '1181' + '\t' + 'log10(conc_solute(Ca[NpO2(OH)2]<+>))' + '\t'+ str(math.log10(myGWB.results('concentration aqueous "Ca[NpO2(OH)2]+"', 'molal')[0])) + '\n') My opinion was that by omitting the "aqueous" behind "concentration" would cause GWB to export the total molality of the given oxidationstate, as defined by the redox species (NpO2+ in this case). Instead, what I observe, is that the concentration of the species NpO2+ is exported. What I would like to have is the total sum of all Np(V)-species in solution. Any ideas appreciated. Helge
  11. Ah, OK. This is what I was looking for. I understand what it is doing now. It is not really a visualization of charge balance showing the major species, just which basis cations and anions make up the solution. That makes sense. I'm not sure what I was thinking with the ionic strength for these charts. Thanks Again for your help. Spencer
  12. Hi Spencer, The bar chart expresses the bulk composition of the fluid in electrical equivalents and does not account for speciation. You can use SpecE8 to calculate the distribution of mass for each component and plot these results in an XY plot as electrical equivalents. The calculated results can be exported and be plotted externally. Please also note that the axis on the bar chart does not represent ionic strength of the fluid. If you want to check if mass balance is honored, you should use molality as the unit. If you add up the concentration of individual species, you will arrive at the bulk composition of that component. Best regards, Jia Wang
  13. Hello Alex, The GWB does not currently include a model for solid solutions. Olivine is a solid solution series with two endmembers, forsterite and fayalite, which are both included in thermo.tdat. You can however add intermediate members with discrete composition to the database if you like. You would need to include the equilibrium constants associated with the mineral reaction. Please don’t post multiple topics about the same question. We hope you enjoy using the GWB. Best regards, Jia Wang
  14. Hello Jen, You can run GWB on a Mac by using a Windows emulator such as Parallels. Another option is to set up dual boot configuration using a program such as Boot Camp. You can find more information here. Best regards, Jia Wang
  15. Hi again Dan, It did the trick; thank you very much!!! We had previously changed the working directory, as well as the directory in which we are building the library, but we had no success. I followed the steps you provided (the screenshot was very helpful) and it's working now. Thanks, Melika
  16. Hi Melika, Yes the screenshot was very useful, thank you for that. I think the main issue is the fact that you are building the DLL in the GWB folder; I ran into many odd issues when attempting to do that as well. I would start by first cleaning up the FeRB files from the GWB folder. To do this you can just manually delete all the FeRB files ( FeRB.cpp FeRB.exp FeRB.dll FeRB.lib etc ) in the c:\program files\gwb folder. While most of these files don't matter, it is vital you delete the FeRB.dll file. Then instead of building directly in c:\program files\gwb I would put all the files from your first post into a folder without any weird Windows restrictions/behavior e.g. create a FeRB folder on the desktop and put all the files there. You can then build the DLL mostly the same way, but you will need some extra flags. You can also build the DLL in a single step instead of compiling and linking separately: cl FeRB.cpp "c:\program files\gwb\x1t.lib" /I"c:\program files\gwb\src" /link /dll /out:FeRB.dll Assuming that succeeds then you can run X1t and properly set the working folder with: "c:\program files\gwb\x1t" FeRB.x1t -cd Here is a screenshot from my machine with using the same Visual Studio versions with GWB14.0.1 Hopefully this helps get you going. -Dan
  17. Hi Dan, I've attached a screenshot of the commands we use to generate the library (not sure if the screenshot is useful to help us figure out the problem). We're using x64 Narrative tools command prompt as you can see in the attached. The two licenses of GWB are installed on separate laptops, so each time we want to run the script, we create a new library on the laptop we're using. We always use "run as administrator" for command prompt and x1t as well. The attached library is created with GWB14 and results in X1t crashing upon running the script. Thanks, Melika FeRB.dll FeRB.exp FeRB.lib FeRB.obj
  18. Does GWB have a substitute mineral for Olivine as it does not appear directly under 'Minerals'?
  19. Dear Jiang Wang, I would like to know the relationship of input parameters of DDL (dielectric double layer) of SCM (surface complex model) betwen Phreeqc and GWB. As shown in the arrachment (File nmae: Phreeqc DDL model input parameters), only Debye length is needed to input. However, if the constant capacitance is slected in the sorbing surface of GWB, I don't know the relationship between Debye length (default value: 1.0E-08 m, for ionic strength=0.001) and capacitance. The potential data can be obtained from Phreeqc output (Phreeqc output_potential) and if the data was input in the GWB, the Kd values were almost the same between GWB and Phreeqc. I am curious about it and your response will be highly appreciated. Polly Tsai
  20. I just downloaded the GWB for students, to give it a try on my Mac, and the window which opened contained many lines of script which began with this: MZêˇˇ∏@»∫¥ Õ!∏LÕ!This program cannot be run in DOS mode. $1∞D9u—*ju—*ju—*j∂fiujw—*ju—+j”—*j∂fiwjd—*j!Új—*j≤◊,jt—*jRichu—*jPEL¨f∫R‡ ^*˝1p@jMQÄît¥P걆òPàp∏.textÙ\^ `.rdataTpb@@.dataòêv@¿.ndata∞†Ä¿.rsrcê±P≤|@@UãÏÉÏ\É} t+É} FãEu ÉHã ®ëBâHPˇuˇu ˇuˇ$r@ÈBSVã5∞ëBçE§WPˇuˇ(r@ÉeÙâE çE‰Pˇuˇ,r@ã}ÉeãLp@ÈÄ∂FR∂VVØUËãœ+MËØ¡¬âMô˜ˇ3“ä∂FQØ¡∂NUØMË¡ã ô˜ˇ∂VTØUËä»∂FPØE¬ô˜ˇ¡·∂¿ »çEÙPâM¯ˇTp@ÉEâEPçE‰Pˇu ˇ0r@ˇuˇ”ÉEË9}ËåwˇˇˇÉ~Xˇteˇv4ˇDp@Ö¿âEtUã} jW«E‰«Eˡ@p@ˇvXWˇHp@ˇuã5<p@Wˇ÷âE çE‰h Pjˇh†ÅBWˇ4r@ˇu Any idea if the program can be run on a Mac, and how I can download/launch it so it will work? Thanks
  21. Hello Jason, I took a quick look at your input files and here are a few suggestions. For alkalinity concentration, you should use meq_acid/l for the unit and not meq/l for HCO3-. This will change your calculation by quite a bit. I also noticed in the basis pane that 1 free kg of H2O is designated but your problem describes a 100 ml sample with a density of 1.01 g/cm3. I would suggest setting the amount of free solvent at 0.1 kg so your calculation is performed at or very close to your sample volume. Another suggestion is to change the value of "reactant times" in the Reactants pane to something like 0.0001. It looks like you created a 10 kg solution of your 36% HCl acid. You won't need to titrate all of it if you are only expecting to see the change you want with a small amount added. Reactants times factors the total amount of your reactant that you are adding to your fluid. You can also turn off precipitation in your React simulation by going to Config --> Option and uncheck precipitation. Unless you are expecting minerals to precipitate during your titration, it might be worth considering turning it off so that mineral precipitation is not a factor in your calculation. I think with these changes, you will get much closer to the field measured volume and mass of HCl added. You can view your result in Gtplot by choosing your x-axis variable as "mass reacted total" under the variable type "Reactant properties" and your y-axis variable as the pH under the variable type "Chemical parameters". For more information on plot configuration, please see section 6.2 XY Plot configuration in the Reaction Modeling User guide. Hope this helps, Jia Wang
  22. Thanks. If I do as you said for the example of sulfate, I get the following for by-component equivalents with the bar graph (169.7 meq/kg for SO4--): Step Xi H2O Al+++ Ca++ Cd++ F- Fe++ H+ K+ Mg++ Mn++ O2(aq) SO4-- SiO2(aq) Zn++ meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg 0 0 0 12.01042 24.50093 0.012581 0.22226 23.2105 16.23034 0.163255 29.09023 67.92366 0 169.7019 0 5.106747 and the following for Total Sulfate Species (91.05 meq/kg) using the xy plot export procedures and selecting only SO4-- species (Total 91.05 meq/kg). Sulfate Species: Rxn progress Al(SO4)2- AlSO4+ CaSO4 Cd(SO4)2-- CdSO4(aq) Fe(SO4)2- FeHSO4++ FeSO4 FeSO4+ H2S(aq) H2SO4 HS- HSO4- KSO4- MgSO4 MnSO4 S-- S2-- S3-- S4-- S5-- S6-- SO4-- ZnSO4 meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg meq/kg 0 1.42095 1.629153 0 0.002644 0 1.338236 0.035607 0 6.387276 0 0 8.57E-82 4.508028 0.01168 0 0 1.58E-92 9.45E-148 1.41E-203 7.52E-257 0 0 75.71746 0 So, it appears there is a mismatch, unless I'm still missing something about how these plots are representing the data?
  23. Hello Spencer, Like I said above, the concentration you enter for Fe++ in the GSS spreadsheet is considered as Fe++ when you are plotting from GSS. So that's why I suggested you adding Fe++ and Fe+++ separately. I don't think the graph is showing twice the ionic strength. If you add the individual species of that component, then you should arrive at the same concentration as shown in the plot. For example, if you summed all the sulfate species concentration and covert to meq/kg, then you should get the same value as seen plotted from the GSS spreadsheet. There should be a section below in your SpecE8 output file that shows you the total component concentration for that species (e.g. SO4--). The bar graph type plot does not plot individual species concentration, only component concentration. You can however retrieve each aqueous species concentration in units of eq/kg and make the plot separately in excel or python. To retrieve those values, you can plot your SpecE8 calculation results in Gtplot (in your SpecE8 window go to Results and click on plot results). An XY plot should pop up, if not, you can go to Plot on the menu bar up to and select XY plot. Double click on the center of the plot to bring up the plot configuration. You can configure one of the axis to show the variable type "species concentrations" and change the units to meq/kg (or eq/kg). Click ok or apply. Then go to the Edit --> copy as --> spreadsheet and paste your result into excel to view. You can manipulate this numerical result externally to plot as you wish. Hope this helps, Jia
  24. Hi Melika, What are you using to compile the dll? Could you provide either the visual studio project file or the commands used to compile the dll? Also be aware that when you compile a dll that the dll in general will only work with the specific version of GWB that it was compiled against. It may sometimes work with other versions of GWB, but you will usually need to recompile. Thanks, Dan
  25. 36% HCL + Chemwaste V1 23JUNE2020.reaReact_output_36% HCL + Chemwaste 23JUNE2020.txt36% HCL only V1 23JUNE2020.reaReact_output_36% HCL Only V1 23JUNE2020.txt Jia, Water Analysis for Geochem workbench.xlsx I have attached the files, but I think an explanation on what I am trying to do might be relevant to make sure I am on the right track. In the field, I took 100 mL of the sample in the attached water analysis and added .269 mL or .3186 Grams of 36% HCL to reduce the pH from 11.5 to 7.038 the specific gravity of 36% HCL is 1.18. What I am trying to do is as follows: 1) replicate this in the simulator. when I do a pH vs volume of 36% hcl graph, it should show me a pH of 7 when I add .269 mL or .3186 Grams of 36% HCL 2) if I show a pH range from 0 to 14, it would accurately simulate the amount of 36% HCL that would need to be added in order to achieve that pH Let me know how the file looks and what I need to do in order to get the desired results. I really appreciate your time helping me with this
  26. Hello Jia, thanks for your reply. yes, of course I am connected to the internet. I will try the offline activation - see how it goes. Cheers, Lisa
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