A system and method for surface characterization of a porous solid or powder sample using flowing gas include mass flow controllers configured to deliver a controllable mass flow of a carrier gas and adsorptive gas to vary concentration of the adsorptive gas flowing through at least one measurement channel containing a sample cell. A concentration detector downstream of the sample cell provides a signal indicative of the adsorptive gas concentration to a controller that determines the amount of adsorptive gas adsorbed and/or desorbed to characterize the surface area, pore volume, pore volume distribution, etc. of the sample material. The detector may include a housing, heat exchanger, thermal conductivity detector, and a temperature regulator.

A system and method for surface characterization of a porous solid or powder sample using flowing gas include mass flow controllers configured to deliver a controllable mass flow of a carrier gas and adsorptive gas to vary concentration of the adsorptive gas flowing through at least one measurement channel containing a sample cell. A concentration detector downstream of the sample cell provides a signal indicative of the adsorptive gas concentration to a controller that determines the amount of adsorptive gas adsorbed and/or desorbed to characterize the surface area, pore volume, pore volume distribution, etc. of the sample material. The detector may include a housing, heat exchanger, thermal conductivity detector, and a temperature regulator.

Embodiments of the invention include a biosensor, such as an implantable biosensor, that includes a sensor material sensitive to at least one analyte in a pressure measurement chamber coupled to a pressure sensor. In embodiments of the invention, a pressure prevailing in the pressure measurement chamber may be determined by the pressure sensor. The sensor material is coupled in the pressure measurement chamber to a compensation material, which includes a relationship between a temperature and a volume of the pressure. The relationship is opposite to a temperature-dependent change in pressure or volume of the sensor material and at least partially compensates for a cross-sensitivity-induced change in volume of the sensor material.

Embodiments of the invention include a biosensor, such as an implantable biosensor, that includes a sensor material sensitive to at least one analyte in a pressure measurement chamber coupled to a pressure sensor. In embodiments of the invention, a pressure prevailing in the pressure measurement chamber may be determined by the pressure sensor. The sensor material is coupled in the pressure measurement chamber to a compensation material, which includes a relationship between a temperature and a volume of the pressure. The relationship is opposite to a temperature-dependent change in pressure or volume of the sensor material and at least partially compensates for a cross-sensitivity-induced change in volume of the sensor material.

A method and system for adsorbed phase activity coefficients for mixed-gas adsorption includes: providing one or more processors, a memory communicably coupled to the one or more processors and an input/output device communicably coupled to the one or more processors; calculating a first gas activity coefficient ?.sub.1 for a first gas using the one or more processors and a first equation; calculating a second gas activity coefficient y.sub.2 for a second gas using the one or more processors and a second equation based on a bulk mole fraction of the first gas; providing the first gas activity coefficient y.sub.1 for the first gas and the second gas activity coefficient y.sub.2 for the second gas to the input/output device; and using the first gas activity coefficient y.sub.1 for the first gas and the second gas activity coefficient y.sub.2 for the second gas in the gas adsorption system.

A method and system for adsorbed phase activity coefficients for mixed-gas adsorption includes: providing one or more processors, a memory communicably coupled to the one or more processors and an input/output device communicably coupled to the one or more processors; calculating a first gas activity coefficient ?.sub.1 for a first gas using the one or more processors and a first equation; calculating a second gas activity coefficient y.sub.2 for a second gas using the one or more processors and a second equation based on a bulk mole fraction of the first gas; providing the first gas activity coefficient y.sub.1 for the first gas and the second gas activity coefficient y.sub.2 for the second gas to the input/output device; and using the first gas activity coefficient y.sub.1 for the first gas and the second gas activity coefficient y.sub.2 for the second gas in the gas adsorption system.

A container for determining the quantity of CO.sub.2 absorbed and/or expelled by a sample of matter over time, including: a bottom compartment designed to receive a sample of matter, a top compartment receiving element for trapping CO.sub.2, positioned in line with and communicating with the bottom compartment, and having an exhaust opening enabling gas to escape from the top compartment after it passes through the receiving element for trapping CO.sub.2, a separation element, disposed between the bottom compartment and the top compartment, configured to enable gas to pass from the bottom compartment to the top compartment.

A method of characterizing free volume of a rock sample includes test operations that measure pressure decay data from stepwise pressurization of the rock sample with a test gas. An initial free volume of the rock sample is calculated as a function of the pressure decay data. An initial maximum storage capacity of the rock sample is derived as a function of the initial free volume of the rock sample. A volume of test gas adsorbed as a liquid is calculated based on the maximum storage capacity of the rock sample. An updated free volume of the rock sample is calculated based on the initial free volume and the volume of the test gas adsorbed as a liquid. An updated maximum storage capacity of the rock sample is derived as a function of the updated free volume. Calculations of the volume of test gas adsorbed as a liquid, the updated free volume and the updated maximum capacity of the rock sample can be repeated until the updated maximum storage capacity and the updated free volume converge respectively to give the maximum storage capacity and free volume of the rock sample.

A method of characterizing free volume of a rock sample includes test operations that measure pressure decay data from stepwise pressurization of the rock sample with a test gas. An initial free volume of the rock sample is calculated as a function of the pressure decay data. An initial maximum storage capacity of the rock sample is derived as a function of the initial free volume of the rock sample. A volume of test gas adsorbed as a liquid is calculated based on the maximum storage capacity of the rock sample. An updated free volume of the rock sample is calculated based on the initial free volume and the volume of the test gas adsorbed as a liquid. An updated maximum storage capacity of the rock sample is derived as a function of the updated free volume. Calculations of the volume of test gas adsorbed as a liquid, the updated free volume and the updated maximum capacity of the rock sample can be repeated until the updated maximum storage capacity and the updated free volume converge respectively to give the maximum storage capacity and free volume of the rock sample.

In an aspect a method is disclosed comprising drawing air into a robotic vapor device, exposing the drawn air to a sensor to detect one or more constituents in the drawn air, determining first measurement data for the one or more constituents of the drawn air via the sensor, transmitting the first measurement data to a computing device via a network, receiving second measurement data from the computing device via the network, determining one or more vaporizable materials to vaporize based on the first measurement data and the second measurement data, and dispensing a vapor comprised of the one or more vaporizable materials.