Overall considerations for instrument design

Even when a laboratory is concerned initially with a single type of measurement, it is inevitable that additional capabilities are soon required. In order to prepare for a broad range of kinetic and equilibrium studies, it is best to plan from the beginning for a full set of instruments and these instruments should, ideally, be designed to  

2 Design strategy derived from the performance goals 

Not all the performance goals listed above are equally important in every measurement some of the goals are even contradictory, so that compromises are necessary. Design simplicity and safety considerations require that compressed gases should be avoided. A modular approach, such as the following, makes it possible to meet most of the goals simultaneously. 

Use a common, semiportable unit to generate and measure pressures and to deliver them to different pressure chambers by a hydrostatic connection. For reliability, use oil for the hydraulic fluid in this unit. 

Confine any liquid-sample solution in a small, interchangeable cell, which should be optimized for each different procedure. Use some type of moving piston or deformable membrane in this cell, so that the pressure is balanced inside and out. 

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