Abstract: A method of determining pore size of a porous material. The method includes saturating the porous material with a conducting liquid. Measuring, with an electro-acoustic device, a phase of the seismo-electric or electro-seismic signal at a single frequency or multiple frequencies. Calculating an average pore size from the measured phase of the seismo-electric or electro-seismic signal at single frequency using a theory that takes into account the hydrodynamic relaxation of the conducting liquid inside of the pores of the porous material. Calculating pore size distribution from the similar measurement conducted at multiple frequencies using the same theory.

Abstract: For use in a sorption analysis system, a method compensating for measuring error due to the time-dependent evaporation of liquid coolant and the resulting change in the level of the coolant and temperature increase around the stem of the sample cell, during a gas sorption analysis of a sample in the sample cell. This error compensation does not inhibit coolant evaporation and is without recourse to mechanical means or other physical contrivances for causing the system to act as if the coolant were not evaporating. This method employs fixed and time-dependent data, including: changing coolant level and sample cell stem temperature changes, both of which can be obtained off-line, cold zone volume changes, and volumes of adsorptive gas transferred into the sample cell, to generate progressive error correction; whereby, system output is being corrected throughout the duration of the sorption analysis.

Abstract: A vacuum pump system for creating a high vacuum (below 10−7 TORR) especially useful for vacuum volumetric measurements such as are performed using a gas sorption analyzer on a particulate sample to determine particulate surface area and porosity using a dry, non-lubricant oil-free vacuum pumping system that includes a turbomolecular drag pump having its high vacuum side connected to a vessel that contains the particulate sample to be analyzed, and in series with a dry, oil-free diaphragm pump whose inlet or vacuum side is connected to the high pressure exhaust side of the turbomolecular drag pump thereby eliminating any possibility of oil vapor contamination of the sample since the turbomolecular drag pump and the diaphragm pump use essentially no oil as lubricants.

Abstract: A high pressure mercury porosimeter for continuous pore volume distribution measurements that simultaneously receives two or more test sample penetrometers, each containing a powder or porous solid sample to be tested. Two or more individual tests can be simultaneously performed per high pressure cycle in a single porosimeter. Only one access port is required to access 2 or more penetrometers greatly increasing sampling throughput, reducing multiple test time requirements without significant equipment cost increase.

Abstract: An adsorption and desorption analyzer for performing analyses on samples comprises a manifold for selectively storing one or two gases or vapors having different critical temperatures, at least two cells constructed and arranged to store a sample for analysis, a supply line having an isolation valve connecting each cell to the manifold, an absolute pressure transducer for monitoring the pressure in the manifold, vacuum means, a microprocessor for controlling the operation of the isolation valves and the application of gas or vapor or vacuum to the manifold and a coupling line having a differential pressure transducer having a smaller range than the range of the absolute pressure transducer, enables an operator to determine data points for characteristics of the samples under study more precisely and more rapidly than is possible using an analyzer having an identical absolute pressure transducer for each cell to determine the characteristics of the samples stored in the cells.

Abstract: An automatic adsorption and desorption analyzer for independently performing analyses on a plurality of powder samples includes a manifold connected through a plurality of independently operated valves to a corresponding plurality of sample cells. A pressure transducer measures the manifold pressure and a plurality of pressure transducers are respectively coupled to the sample cells to independently measure the pressure at each of the sample cells. The system measures the volume of gas adsorbed (desorbed) by each of the samples that is required to establish specified equilibrium pressures at the sample cells, thereby to provide pressure-volume points which can be used to prepare adsorption (or desorption) isotherms, BET curves, and other information concerning the properties of the samples.