The invention relates to user located production of a mixture of substances (3). Stored (S1) in a computer database (1) is assignment information (52) relating to a plurality of storage assemblies (51), each storage assembly comprising a plurality of storage elements, each storage element having stored a substance of a particular type, the assignment information (52) providing for each storage element an assignment of a property of the respective storage element to the substance stored in the respective storage element. Determined is first assignment information (52) of a first storage assembly (51) being arranged in a user located production device (2). Provided is a mixture definition (3) defining the mixture of substances. Determined is production information based on the first assignment information (52) and based on the mixture definition (3), the production information including a definition of a subset of storage elements of the first storage assembly (51), the production information enabling the production of the mixture of substances (3) with the user located production device (2).

A reaction method with a homogeneous-phase supercritical fluid includes introducing a first fluid into a mixing chamber. A mass is less than or equal to that can be absorbed by the molecular sieve component, totally absorbing the first fluid by the molecular sieve component. A second fluid is introduced into the mixing chamber with a mass being greater than that can be absorbed by the molecular sieve component. A temperature and a pressure in the mixing chamber are adjusted to a critical temperature and a critical pressure of the second fluid, respectively, releasing the first fluid in supercritical phase from the molecular sieve component into the mixing chamber, followed by homogeneously mixing with the second fluid in supercritical phase in the mixing chamber to obtain a homogeneous-phase mixing fluid. The homogeneous-phase mixing fluid is then introduced into a reaction chamber connected to the mixing chamber.

Systems and methods are described for dissolving ammonia gas in deionized water. The system includes a deionized water source and a gas mixing device including a first inlet for receiving ammonia gas, a second inlet for receiving a transfer gas, and a mixed gas outlet for outputting a gas mixture comprising the ammonia gas and the transfer gas. The system includes a contactor that receives the deionized water and the gas mixture and generates deionized water having ammonia gas dissolved therein. The system includes a sensor in fluid communication with at least one inlet of the contactor for measuring a flow rate of the deionized water, and a controller in communication with the sensor. The controller sets a flow rate of the ammonia gas based on the flow rate of the deionized water measured by the sensor, and a predetermined conductivity set point.