Joint Expert Speciation System (JESS) is a package of computer software and data
developed collaboratively at
Murdoch University
Murdoch University is a public university in Perth, Western Australia, with campuses also in Singapore and Dubai. It began operations as the state's second university on 25 July 1973, and accepted its first undergraduate students in 1975. Its n ...
and elsewhere by researchers interested in the
chemical thermodynamics
Chemical thermodynamics is the study of the interrelation of heat and work with chemical reactions or with physical changes of state within the confines of the laws of thermodynamics. Chemical thermodynamics involves not only laboratory measurement ...
of water solutions with important applications in industry, biochemistry, medicine and the environment. Using information from the chemical literature, stored in databases for numerous chemical properties, JESS achieves coherence between frequently conflicting sources by automatic methods.
JESS places a strong emphasis on the concept of
chemical speciation (''i.e''. the identity and relative abundance of different chemical entities which may be present), which can be predicted from known
stability constants of metal-ligand complexes. Characteristic quantities for water solutions such as
solubilities,
equilibrium constant
The equilibrium constant of a chemical reaction is the value of its reaction quotient at chemical equilibrium, a state approached by a dynamic chemical system after sufficient time has elapsed at which its composition has no measurable tendency ...
s,
activity coefficient
In thermodynamics, an activity coefficient is a factor used to account for deviation of a mixture of chemical substances from ideal behaviour. In an ideal mixture, the microscopic interactions between each pair of chemical species are the same (or ...
s,
heat capacities and densities can be calculated from changes in the chemical speciation.
Recent examples of practical problems that can be investigated by JESS include
kidney stone
Kidney stone disease, also known as nephrolithiasis or urolithiasis, is a crystallopathy where a solid piece of material (kidney stone) develops in the urinary tract. Kidney stones typically form in the kidney and leave the body in the urine s ...
s (mineral precipitation and dissolution in the kidney) and
Wilson’s disease (copper physiology in the human eye).
At the core of the software package is a thermodynamic database called the ‘JESS Parent Database’ (JPD). JPD now comprises over 80,000 chemical reactions for which some 280,000 equilibrium constants and other thermodynamic parameters have been recorded from the chemical literature. Over 70,000 distinct chemical species are involved. The whole contents of this database in a set of associated PDF documents, which have been specifically prepared for free, widespread scientific dissemination, are available at the Zenodo repository.
References
External links
* {{official, http://jess.murdoch.edu.au/jess_home.htm
Chemistry software