PSI Website Information: If you see this message, then either your browser doesn't support Javascript or Javascript is disabled. You might want to enable it for this site?

GEM Software (GEMS) Home

GEM Software Home

GEM-Selektor v.3

GEMS3K Codes

GEMSFITS Codes

Terms & Licenses

GEMS Default TDB

TSolMod Library

Publications

GEMS News Ticker

Example & Test Projects

Links & Contributions

Get GEM Software
(in construction)

LES PSI Homepage

Updated:
06.11.2024

GEM-Selektor News Ticker

06 November 2024:

New Release A new version of GEMS-Selektor v3.9.7 was released for Windows 10/11 and Linux,and MacOS version is now available for downloading from the GEM-Selektor web page. The version contains several bugfixes and improvments:

* fix for calculation of ReacDC record properties at Tr and Pr other than 25 C 1 bar
* fix water standard properties as in CODATA89/NEA, conversion from steam table
* fix for assignment of water properties for LVS model above critical T
* GEMS-227: Fixed 'gems' application not responding when a lot of systems to update.
* GEMS-227: Skip copy not connected db files when creating gems project by template
* GEMS-226: Added buttons 'Select all' and 'Clear Selection' on the basis configuration of a new Modelling Project.
* GEMS-224: Bugfixed: avoid old records selections in case of 'clearing all' mode for reacdc records
* GEMS-215: Bugfixed: the folder Library/Gems3/ is created without the projects/ subfolder.

27 June 2023:

Attention (hotfix)! There were user reports that the latest GEM-Selektor v.3.9.6 package for Windows 10/11, when installed in a user directory for the first time, fails to start. Beginning from today, the installer for Windows is replaced by a newer installer containing a hot-fixed package expected to start normally in any case. The previous installer (from 20 May 2023) is still available for those who do not want to de- and re-install GEMS396 and would rather use the workaround now added to the Installation instructions (pdf) file, section 1.1A. We strongly recommend all GEMS for Windows users to update to this hotfix release. Similar issues with MacOS and Linux installations of GEM-Selektor have been found, and the installers replaced with hot-fixed ones.

20 May 2023:

GEM-Selektor version 3.9.6 hotfix (rev. 7f2d47b.9a8c970) code package is now available for downloading from the GEM-Selektor web page, replacing the installers of v.3.9.6 released on 10.May 2023. With this hotfix, all the output from the new logging of GEMS operation will be written into a "/logs" subfolder in the user's work folder, for instance, "C:\Users\<username>\Library\Gems3\logs" (where the user can easily check the logs). This update also fixes the temporary issue with MacOS installation mentioned below: now GEM-Selektor can be launched as usual, by clicking in Finder on "gems3.app" or by clicking on the "GEMS3" icon in the Dock. We strongly recommend all users to update to this hotfix release, also those who have already used the installer from 10.May 2023.

10 May 2023:

GEM-Selektor version 3.9.6 (rev. 78a6759.f9bc3d0) code package, built using Qt5.15 or Qt6.2 LTS, is now available for downloading from the GEM-Selektor web page. This is a bugfix interim release, with several reported bugs corrected such as uncaught math errors, memory leaks or crashes due to the use of new functionality such as the export to GEMS3K files with ThermoFun local JSON database and the new logging system using spdlog. This update is recommended for all users, especially on Linux where we use now a convenient AppImage bundle format. Note that on MacOS, temporarily the GEM-Selektor v.3.9.6 can only be started from terminal or from Finder by diving into gems3.app Contents => MacOS => clicking on gems3 executable file; this issue will hopefully be fixed until the next release.

20 June 2022:

GEM-Selektor version 3.9.5 (rev. 9f3dc56.6dae7a9) code package, built using Qt6.2 LTS, is now available for downloading from the GEM-Selektor web page. This is a bugfix release, with several reported bugs corrected such as: deviations of Pitzer activity coefficients of aqueous species (tested against the salt solubility data and PHREEQC calculations in the same system); crash when opening a project with some ReacDC records containing "empty" (not recalculated inconsistent) data, e.g. in ClaySorMo and ClaySorIll projects (hint: replace these test projects in your Library/GEMS3/projects copying them from gems3-app Resources/projects); default number of displayed digits 8 sometimes caused ugly rendering such as 1.2600001, and was changed to 7 in "Preferences" to avoid such artifacts. This bugfix update is recommended for all users, especially those working with brines and applying the Pitzer activity model.

14 April 2022:

GEM-Selektor version 3.9.4 (rev. 58a7959.1e0be4a) code package, built using Qt6.2 LTS, is now available for downloading from the GEM-Selektor web page. This is a bugfix release, with several reported bugs corrected such as wrong calculations of standard enthalpies of aqueous species from DComp data in MTParm and RTParm (this also affected export of enthalpies into GEMS3K I/O files). This recommended update is a "must do" for all users working with enthalpies and heat effects e.g. in process or reactive transport simulations.

23 December 2021:

GEM-Selektor version 3.9.3 (rev. 65db334.18b094c) code package, built using Qt6.2 LTS, is now available for downloading from the GEM-Selektor web page. This is a bugfix release, also adding more functionality to GEM2MT simulations: now the modification of nodes at a time step in the middle of the simulation works if this modification is coded in the control script. More memory leaks were removed; better handling of math exceptions also implemented. Initial configuration files of GEM-Selektor are now provided in JSON format for better compatibility. The graphics in runtime mode of Process simulations has been improved. Minor fixes are reflected in commit messages in the source code repository. An upgrade to this version of GEM-Selektor surely makes sense.

05 November 2021:

GEM-Selektor version 3.9.2 (rev. 96323c0.8986188) code package, built using Qt6.2 LTS, is now available for downloading from the GEM-Selektor web page. This bugfix release has several important issues fixed. GEM2MT simulations of box-flux 'B' type dynamic reactive transport now run correctly, including mobile groups of solid/liquid phases, various types of first-order fluxes and sinks, etc. The large definitions of SIT aqueous phase are now automatically compressed upon creation of a new modelling project including the list of interaction parameter comments, and re-compressed when cloning the project into an extended one. Some "yes/no" dialogs were extended into "yes/no/yes-to-all/no-to-all" style. The GtDemo wizard was re-arranged for early selection of records to sample in a way consistent with previously improved ReacDC and Phase wizards. The GEMS3K module was enhanced with much more extensive handling of math exceptions, warnings and error messages. GEMS3K can now read/write files in JSON and exchange data in memory as JSON strings. GEM-Selektor can export GEMS3K files in JSON format and backup/restore all types of database records in JSON files (this is more reliable than old customary text format for backup/restore). Numerous minor fixes and improvements are reflected in source code repository commit messages. In view of all this, an upgrade to this version of GEM-Selektor is highly recommended.

17 June 2021:

GEM-Selektor version 3.9.0 (rev. e7e92e0.8bcdafa) code package is now available for downloading from the GEM-Selektor web page. This version contains many bugfixes and significant changes in the user interface. The comment lines for the SysEq record are now visible and editable completely in both Recipe Dialog and in the main system widget, to encourage users better document their work. The ReacDC wizard and Phase wizard underwent radical changes to become more logical: the selection of chemical species (dependent components) involved into a reaction or a phase occurs now at the beginning of the wizard configuration process, not after it, as before. This also allows to add better consistency checks among various dimensions and modes, which was not possible before (new checks will be added into the next release). In addition, this is the first release using the Qt6.1 framework - a major upgrade from the Qt5 framework maintained during almost 9 years. Help pages were also extended/corrected to a significant extent. The look and feel on high-resolution monitors up to 4k was improved, especially in Windows, even more. The installers, both off-line and on-line, are built using the Qt Installer Framework (QtIFW) version 4. The upgrade to this version is highly recommended.

07 December 2020:

GEM-Selektor version 3.8.0 (rev. 50e150b5.2888e2a) code package is now available for downloading from the GEM-Selektor web page. This release contains important bugfixes, including one in the GEM2MT calculations and another in the implementation of automatic compression of interaction parameters table in sublattice (multi-site) Berman and CEF solid solution models upon removal of some end members. The plot in the GraphDialog can now be copied on right-mouse click as image to clipboard or saved into an image file. The look and feel on high-resolution monitors up to 4k was improved, especially in Windows. Attention! Starting from v.3.8.0, we distribute online installers for Windows and MacOS that are built in Qt Installer Framework. These installers automatically download and install GEM-Selektor and optionally GEMS3K and (coming soon) GEMSFITS codes. In Windows10, the code packages by default install into the user folder (C:\Users\<you>\GEMS3) in order to avoid problems for non-admin users; the user's modelling projects are now located in the user folder (C:\Users\<you>\Library\Gems3\projects\) as well. In MacOS, default locations of the program (/Users/<you>/GEMS3/Gems3.app) and the users projects (/Users/<you>/GEMS3/Library/Gems3/projects/) are now similar to those in Windows10. This location is safe to persist even after the GEMS codes will be upgraded or completely removed using C:\Users\<you>\GEMS3\MaintenanceTool.exe (in MacOS: /Users/<you>/GEMS3/maintenancetool.app). We highly recommend to upgrade your GEM-Selektor installation to this version (previous installations will not be affected).

25 March 2020:

GEM-Selektor version 3.7.0 (rev. 50e150b5.2888e2a) code package is now available for downloading from the GEM-Selektor web page. This release contains a significant improvement of GEMS3K numerical stability and faster convergence (the Pa_DK tolerance needs to be set 0.5 to 1 orders higher than before, e.g. to 1e-5 instead of 1e-6). Another improvement is the implementation of automatic compression of interaction parameters table in sublattice (multi-site) Berman and CEF solid solution models upon removal of some end members due to narrower list of Independent Components in modelling project or in the system. There were also improvements in documentation and wizard scripts for 'R' - type processes (SFTR- Single Flow-Through Reactor) mode. We highly recommend to upgrade your GEM-Selektor installation to this version.

29 October 2019:

GEM-Selektor version 3.6.0 (rev. b17fbf5.7940cbb) code package is now available for downloading from the GEM-Selektor web page. Starting from this release, the source code of GEM-Selektor GUI part is distributed under the GPL v.3 license because of replacing the graphics dialog module with its implementation based on QtCharts. The GEMS3K numerical code part is distributed under the LGPL v.3 license, as before. This release also contains some relevant bugfixes in the GEM2MT module (random-walk algorithm) and in the calculation of CEF sublattice solid solution models. The default database now contains some thermodynamic data and phase definitions for the ClaySor sorption models for illite and montmorillonite, described in detail in NAB 18-027 (2019) report.

19 May 2019:

GEM-Selektor version 3.5.0 (rev. 80423ef.707e5ad) code package is now available for downloading from the GEM-Selektor web page. This is a moderate improvement release, featuring simple reactive transport simulation tools (GEM2MT module, Process simulations in R mode) in a revised, much better documented and ready to use shape. Explore the respective wizards to create in minutes some stepwise flow-through reactor leaching or flushing simulations (Process R mode), then switch to GEM2MT module with a sequential reactor chain (S mode), box-flux chain (F mode) and generic box-flux scheme with internal sources/sinks (B mode), as well as 1-D advection-dispersion (A mode) or advection-diffusion (W mode) models. All these modes are well suited for studying water-rock (or water-cement) interactions at different levels of complexity. This release also contains bugfixes in GEMS3K and GEM-Selektor improving the runtime performance.

07 January 2019:

GEM-Selektor version 3.4.5 (rev. dcffc63.39b782e) code package is now available for downloading from the GEM-Selektor web page. This is a bugfix release, fixing issues with the reciprocal terms used in addition to Berman sublattice solid solution model, and with the new conveniences in the GraphDialog (added tooltips and "what's this").

14 December 2018:

GEM-Selektor version 3.4.4 (rev. 0c19d8d.4abd759) code package is now available for downloading from the GEM-Selektor web page. This bugfix release is also the first truly 64 bit version for Windows, built with the Qt 5.12 toolkit and MinGW73_64 compiler suite. It runs on Windows7, 8, 10; Macos 10.12 - 10.14; on (k)ubuntu linux 16.04, 18.04). Improvements include highlighting plot curves and symbols in the Graphics Dialog by clicking on their legend names. This can save a lot of time when there are many plots and one needs to identify them quickly.

21 November 2018:

GEM-Selektor version 3.4.3 (rev. 597a65a.4abd759) code package is now available for downloading from the GEM-Selektor web page. This is a bugfix release built with the Qt 5.11.2 toolkit (runs on Windows7, 8, 10; on Mac OS X 10.11 - 10.14; on (k)ubuntu linux 16.04, 18.04). Many bugfixes done; added help and documentation about CEF and MBW sublattice solid solution models implementations. The GEM-Selektor code v.3.4.3 can also be cloned from its public Git repository here and built as described in the Overview there (this could make sense for users of linux other than (k)ubuntu).The corresponding open-source standalone GEMS3K code v.3.4.3 can also be cloned from its public git repository here.

24 July 2018:

GEM-Selektor version 3.4.2 (rev. aee0d15.a86951d) code package is now available for downloading from the GEM-Selektor web page. This is a bugfix release built with the Qt 5.11 toolkit (runs on Windows7, 8, 10; on Mac OS X 10.11 - 10.13; on (k)ubuntu linux 16.04, 18.04). Many bugfixes done, improvements include ClaySor sorption model and Vinograd MBW solid solution model implementations.

07 April 2017:

GEM-Selektor version 3.3.5 (rev. ee754fe.a73e674) code package is now available for downloading from the GEM-Selektor web page. This is a bugfix release built with the Qt 5.7 (runs on Windows7, 8, 10; on Mac OS X 10.11, 10.12; on (k)ubuntu linux 16.04). Bugfixes and improvements include more robust kinetics simulations and (fixed) 1-D reactive transport (advection-dispersion) simulations with finite-differences method. The corresponding GEMS3K code v.3.3.5 (rev. a73e674) can be cloned from its Bitbucked git repository, https://bitbucket.org/gems4/gems3k.

17 October 2016:

GEM-Selektor version 3.3.4 (rev. 3cecb08.8df0cc1) code package is now available for downloading from the GEM-Selektor web page. This is a bugfix release built with the Qt 5.7 (runs on Windows 7, 8, 10; on Mac OS X 10.11; on (k)ubuntu linux 16.04). Bugfixes and improvements include memory leaks; refreshed Flowline test project; and corrected output of thermodynamic properties of liquid water and water vapor around saturated water vapor curve at Psat in systems where both aqueous phase and gas phase are present. The corresponding GEMS3K code v.3.3.4 (rev. 8df0cc1) can be cloned from its Bitbucked git repository, https://bitbucket.org/gems4/gems3k.

18 January 2016:

The open-source GEMS3K code under LGPL3 (v.3.3, compatible with GEM-Selektor v.3.3.3) can now be found in a mirror Git repository on Bitbucket, URL: https://bitbucket.org/gems4/gems3k. Easier to get than ever before!

09 December 2015:

MINES 2015 v.1 is a thermodynamics database prepared for modeling magmatic-hydrothermal ore forming processes by Prof. Alex Gysi (Colorado School of Mines, USA). It is now available for downloading from the MINES TDB web page. Please see also the GEMS Contributors page. A welcomed extension of our geography and coverage of modelling topics, applications and tutorials!

13 April 2015:

The GEM-Selektor version 3.3.3 (rev. 2646.1036) code and database package now becomes available for downloading from the GEM-Selektor web page. This is a next sub-version release built with the Qt version 5.4.1 (runs also on Mac OS X 10.9, 10.10). GEM-Selektor v.3.3.3 was in internal development for over two years; it contains important extensions of the Phase record format and data structure, as well as the Phase remake wizard, made in order to accommodate more flexible mixing models (TSolMod), built-in mineral-water reaction kinetics (TKinMet), and a new implementation of sorption and surface complexation models (TSorpMod; work still in progress). Some test projects were also improved or updated. In the DB.default database, all Phase records were converted into the new extended format, and the default PSI/Nagra thermodynamic database was updated to status 12/07 (see https://www.psi.ch/en/les/software-and-database).

For backward compatibility, all modelling projects created in GEM-Selektor v.3.2.x or earlier, will open and work normally in GEM-Selektor v.3.3.x; accordingly, GEMS3K I/O files exported from GEM-Selektor v.3.2.x are readable and will work in coupled codes and examples using GEMS3K v.3.3.x. A prerequisite of this is that no Phase record is created or remade in such a project having the "old" record format.

Immediate extension of old modeling projects in GEM-Selektor v.3.3.x with newly created Phase records, remaking existing Phase records, or via Project remake/extension wizard is possible. Before doing that, the user needs only once to open the project; switch to Database Mode; open the Phase window; and remake one-by-one all Phase records available in the project (saving each record back after remake). This will ensure that new or modified phases with extended structure and functionality will work correctly. Note that if some Phase records remain in the "old" format (i.e. not remade) then this will lead to errors or crashes during calculations of equilibria in systems from this project.

It is essential that ALL Phase records go once through the Phase remake wizard! Even opening and closing a modeling project once in the GEM-Selektor v.3.3.x will render this project unusable in earlier versions of GEM-Selektor (3.2.x or less). For these reasons, if you have used GEM-Selektor v.3.2.x or earlier, we recommend not to upgrade it, but to install GEM-Selektor v.3.3.x to a new location in your PC, check it, and then copy your old modelling projects into the work project directory of the new version (usually like \MyGEMS33\Library\Gems3\projects).

23 April 2014:

GEM-Selektor version 3.2.3 (rev. 2554.952) code package becomes available for downloading from the GEM-Selektor web page. This is a bugfix release built with the Qt version 5.2.1 (runs also on Mac OS X 10.9).

14 March 2014:

GEM-Selektor version 3.2.2 (rev. 2530.930) code package becomes available for downloading from the GEM-Selektor web page. This is a bugfix release built with the Qt version 5.2.1 (runs also on Mac OS X 10.9). To take advantage of the improved GraphicsDialog, the plots in old projects (created with GEM-Selektor 3 before rev. 2370) need to be customized once and saved in the respective Process, GtDemo or RTparm database records.

06 November 2013:

GEM-Selektor version 3.2.1 (rev. 2482.890) code package becomes available for downloading from the GEM-Selektor web page. There were minor corrections in the updated PSI-Nagra 12/07 default thermodynamic database. A small but useful Phase Information wizard was added to help the user better navigate between Dependent Components and Phases in pages displaying the setup of chemical system. Changes also include several bugfixes, help pages database extensions, and executable files built using Qt version 5.1.1. To take advantage of the improved GraphicsDialog, the plots in old projects (created before release of GEMS 3.2 rev. 2370) need to be customized once.

30 April 2013:

GEM-Selektor version 3.2.0 (rev. 2370.830) code package becomes available for downloading from the GEM-Selektor web page. The default Nagra-PSI thermodynamic database is replaced with the updated PSI-Nagra 12/07 thermodynamic database. The old GraphicsDialog is replaced with new GraphicsDialog that uses the Qwt library and is capable of producing good-quality plots with several absicssas, which can be saved into files both in bitmap (.png, .jpg, ...) and vector (.svg, .pdf, .ps) formats. Latest changes also include bugfixes, further extended help pages database, and executable files built using Qt version 5. To take advantage of the improved GraphicsDialog, the plots in old projects will need once to be customized.

20 December 2012:

GEM-Selektor version 3.1 (GEMS3.1) rev. 2292.780 code package is available for downloading from the GEM-Selektor web page. Latest changes include numerous bugfixes, much improved and extended help pages database, and refurbished Elements Wizard with a new dialog that lets the user to select built-in thermodynamic database(s), subdatabase(s), and independent components to be used in creating or expanding modeling projects. This was done in preparation for the forthcoming release of updated built-in PSI-Nagra chemical thermodynamic database.

30 September 2012:

GEM-Selektor version 3.0 (GEMS3.0) is here!. After 3 years of intensive development and testing, the GEMS3 code is ready for web distribution (for Windows XP/7/8; Mac OS X; and Linux desktop PC paltforms). Major new features of GEMS3 include: the efficient and robust GEMS3K numerical kernel with excellent mass balance precision, the same as in the standalone GEMS3K code; the TSolMod class library with >20 non-ideal mixing phase models; the multi-document-frame GUI based on Qt4.8 toolkit; new Remake wizards and System Recipe wizard; versatile Qt4-based Help system with full search functionality and revised contents including the Tutorial; the enhanced Graph Dialog; many efficiency improvements and bugfixes. Please, check the GEM-Selektor web page for details and downloads.

24 October 2011:

UPGRADE TO VERSION 3.0 in preparation. After a 2-years period of intensive development and testing within the internal GEMS Wiki community, the GEMS3 code becomes mature enough for web distribution (for Windows XP/7; Mac OS X; and KDE-based Linux paltforms). Major new features of GEMS3 include: the efficient and robust GEMS3K numerical kernel with excellent mass balance precision, the same as in the standalone GEMS3K code; the TSolMod class library of >20 multicomponent phase models; the GUI based on Qt4.7; new Remake wizards and System Recipe wizard; versatile Qt4-based Help window with full search functionality; the revised run-time context-sensitive help database including the Tutorial; the enhanced Graph Dialog; many small efficiency improvements and bugfixes. Please, see the Status Page for details, and check the main GEMS web page for the launch date.

05 November 2009:

BUGFIXED INTERIM RELEASE (build 1453) of GEMS-PSI version 2.3.1 rc9 for download for Win32 XP/Vista. Please see
bugfix_log file for details. Installers for Linuxes and MacOS X coming soon!

28 August 2009:

INTERIM RELEASE of GEMS-PSI version 2.3.1 rc9 is now available for download for Win32 XP/Vista. This release contains numerous improvements in the GEM IPM2 solver, and will be the last one before a major upgrade to version 3 based on Qt4 GUI. Currently, GEMS version 3 is under extensive testing. We hope to release it as beta-version as soon as it will be fully functional.

09 February 2009:

INTERIM RELEASE of GEMS-PSI version 2.3.0 rc8 is now available for download for Win32 XP/Vista; Linux 32/64 rpm, Linux32 deb, and Intel Mac OS X 10.5 platforms. In this version of GEM-Selektor, a number of mixing models for condensed phases was added, in particular, Pitzer (HMW) model for aqueous activity coefficients. Treatment of metastability constraints for reproducing mineral dissolution/precipitation kinetics has been improved. Error diagnostics in the GEM IPM kernel has been made more thorough and strict to provide more information. Smart initial approximation mode was implemented to accelerate calculations.

25 July 2008:

BUGFIX RELEASE of GEMS-PSI version 2.2.4 rc7 is now available for download for Win32 XP/Vista; Linux 32/64 rpm, and Intel Mac OS X 10.5 platforms. In this version of GEM-Selektor, a mismatch in representation of output activities and activity coefficients has been fixed. This mismatch is potentially important for calculation of equilibria involving concentrated aqueous solutions. A test project (suggested by B.Lothenbach) is provided here; using this project with this and any older version of GEM-Selektor for comparisons, you will be able to see the magnitude of bias corrected by the present bugfix. In old projects where the ionic strength is less than 0.5 m, the bias is usually small and hardly visible on the Process or GtDemo plots. The detailed description of the mismatch and how it has been corrected is provided in the (updated) file Activity-Coeffs.pdf.

19 May 2008:

BUGFIX RELEASE of GEMS-PSI version 2.2.3 rc6 is now available for download for Win32 XP; Linux 32/64 rpm, and Intel Mac OS X 10.5 platforms. In this version of GEM-Selektor, a few small annoying bugs were fixed, and some documentation extensions made (in particular, for using Pronsprep algorithms in ReacDC module). More example Process scripts (written by Th.Wagner) for sequential reactors mode were added as well.

This version of GEMS-PSI, for the first time, is provided as a .deb package for the Kubuntu 8 "Hardy Heron" 32-bit linux with KDE-3. We hope that this development will further expand the GEM-Selektor user community to Southern Hemisphere.

31 March 2008:

INTERIM RELEASE of GEMS-PSI version 2.2.3 rc5 is now available for download for Win32 XP; Linux 32/64 rpm, as well as for Intel Mac OS X 10.4 and 10.5 platforms. In this version of GEM-Selektor, the "Smart Initial Approximation" (SIA) mode has been further improved and tested. There were also numerous changes in the GEMIPM2 kernel code aimed at better reproducibility of results in automatic initial aproximation. Three methods of temperature/pressure extrapolation for aqueous complexes and non-polar dissolved species were built-in (contributed by Dr. Th. Wagner, ETHZ), documentation pending.

13 February 2008:

INTERIM RELEASE of GEMS-PSI version 2.2.2 rc4 is now available for download for Win32; Linux 32/64 rpm platforms; installers for Apple G4/G5 and Apple Intel PCs are coming soon. This is the first released version of GEM-Selektor where a "Smart Initial Approximation" (SIA) mode can be used e.g. in Process Simulators. Depending on the system size, this accelerates calculations 5 times and more compared with version 2.2.1, or 10 to 60 times compared with versions 2.2.0 rc0 or earlier. The optional SIA mode needs an interim period of extensive testing.

07 January 2008:

MAINTENANCE RELEASE of GEMS-PSI version 2.2.1 rc3 is now available for download for Win32; Linux 32/64 rpm platforms, as well as; (after 2 years break) for Apple G4/G5 PCs. We also provide for the first time the installation bundle for Apple Intel PCs (for now, Mac OS X 10.4 only). The variant for Mac OS X 10.5 may be expected in the near future.

07 November 2007:

NEW RELEASE! GEMS-PSI version 2.2.0 rc2 code is now available on our new web page (https://gems.web.psi.ch) for download for Win32 and Linux rpm platforms. This version uses the performance-optimized GEM IPM-2 numerical engine which runs 2 to 30 times faster than that in previous versions. It also incorporates important bugfixes, some of which result in improved quality and precision of calculated phase assemblage and speciation. We highly recommend upgrading to the latest GEMS version!

03 August 2007:

COMING SOON! New release of GEM-Selektor code - version 2.2.0 release candidate - will be available for download for Win32 and Linux rpm platforms. This version uses the performance-optimized GEM IPM-2 numerical engine which runs 2 to 30 times faster than that in previous versions.

From version 2.2.1 on, the GEM solver will also be available as a standalone batch program GEMIPM2K which can be coupled with an existing or a new fluid-mass-transport, reaction path, or sensitivity analysis code, including those running on high-performance computers and clusters.

A major extension in version 2.2.0 is related to built-in implementations of models of non-ideal mixing in multi-component solid, liquid solutions and fluids (see List of Changes). Numerous bugfixes (see List of Corrections) result in unmatched stablilty of the program and in a better convergence than it was possible before.

31 August 2006:

New release of GEM-Selektor code - version 2.1.2 (release candidate 3) - is now available for download (for Win32 and Linux 32/64 platforms). This version contains an upgraded GEM IPM-2 numerical engine that uses the JAMA C++ TNT numerical algebra package; due to this, GEMS runs faster and stabler as previously, and converges better. For bugfixes, see List of Corrections; for extensions, see List of Changes. The online Screenshot tutorial has been revised and extended with sections on surface complexation modeling, including setup of MUSIC-type GEM SCMs.

31 October 2005:

COMING SOON! After 13 months of development, a major new release of GEM-Selektor code - version 2.1.0 (release candidate 0) - will be available for download within next days. This version contains many bugfixes (several important ones, see List of Corrections) and extensions (see List of Changes) including new CD-MUSIC implementation of surface complexation models with more precise surface activity coefficient terms replacing the older SAT (surface activity terms).

07 September 2004:

GEM-Selektor v. 2.0.1-rc7 (release candidate 7) now replaces the release candidate 6.

This bugfix release is available for for Win32, Linux and Mac OS X. It fixes a problem with database file compression function (see List of Corrections for details).

03 August 2004:

GEM-Selektor v. 2.0.1-rc6 (release candidate 6) is now available for downloading for Win32, Linux and Mac OS X !

This is the first release available for all three major computing platforms. It contains many improvements in the graphical user's interface (see List of Changes for details).

30 June 2004:

GEM-Selektor v. 2.0.0-rc5 (release candidate 5) is now available for downloading! Contains bugfixes of low-to medium importance (see List of Corrections and List of Changes for details).

31 October 2003:

GEM-Selektor v. 2.0.0-rc4 (release candidate 4) is now available for downloading! It is the first release that comes as a real installer for Win32 (creates shortcuts, registry entries, etc.) and can be deinstalled in a standard way.

25 September 2003:

GEM-Selektor v. 2.0.0-rc3 (release candidate 3) is now available for downloading! See List of Changes for details.

Check the Screenshot online tutorial - now strongly extended to aqueous partitioning equilibria involving solid solutions and surface complexation.

18 August 2003:

GEM-Selektor v. 2.0.0-rc2 (release candidate 2) is now available for downloading! See List of Changes for details.

02 April 2003:

GEM-Selektor v. 2.0.0-rc1 (release candidate 1) is now available for downloading! See List of Changes for details.

31 March 2003:

The "complementary" part of the Default chemical thermodynamic database is now extended with ca. 570 organic aqueous species imported from the Slop98.dat database (http://epsc.wustl.edu/geopig).

14 March 2003:

The on-line Screenshot Tutorial is now extended to show how to model irreversible mass transfer using Process Simulators and how to plot various results of such simulations using GtDemo data samplers.

13 March 2003:

The GEMS package download page now explains what to do if you experience problems with downloading GEM-Selektor installation files.

Last updated: 06.11.2024