A residual gas volume measuring device to accurately measuring volume of residual gas while preventing deterioration in a pump that pressurizes an airtight container. This device includes a second pipe 50 through which an airtight container filled with a basic carbon dioxide absorbing liquid and a second reservoir retaining pressurization water in communication with each other, a section closer to the airtight container filled with the carbon dioxide absorbing liquid, and a section closer to the second reservoir which is filled with the pressurization water; and a pump provided in the section of the second pipe filled with pressurization water. Before residual gas is introduced into the airtight container, the pump sends the pressurization water in the second pipe toward the second reservoir, and after the residual gas is introduced into the airtight container, the pump sends the pressurization water in the second pipe toward the airtight container.

A method for surface characterization of a porous solid or powder sample using flowing gas includes a controller that controls mass flow of a carrier gas and an adsorptive gas to form a mixture having a target concentration of the adsorptive gas over the sample, determining adsorptive gas concentration based on signals from a detector disposed downstream of the sample, automatically repeating the controlling and determining steps for a plurality of different target concentrations, and generating an isotherm for the sample based on the adsorptive gas concentration for the plurality of different target concentrations. The method may include immersing the sample in liquid nitrogen to cool the sample for all, or at least a portion of each of the different target concentrations. The target concentrations may vary from less than 5% to greater than 95%, and may vary in a stepwise manner.

A method for surface characterization of a porous solid or powder sample using flowing gas includes a controller that controls mass flow of a carrier gas and an adsorptive gas to form a mixture having a target concentration of the adsorptive gas over the sample, determining adsorptive gas concentration based on signals from a detector disposed downstream of the sample, automatically repeating the controlling and determining steps for a plurality of different target concentrations, and generating an isotherm for the sample based on the adsorptive gas concentration for the plurality of different target concentrations. The method may include immersing the sample in liquid nitrogen to cool the sample for all, or at least a portion of each of the different target concentrations. The target concentrations may vary from less than 5% to greater than 95%, and may vary in a stepwise manner.

A method and apparatus for determining content of adsorbed gas in a deep shale, and a server, wherein experimental tests are combined with molecular dynamics models. Firstly, tests are performed on a core sample of a target area at various temperatures in a first-class pressure environment with low pressure to obtain shale gas adsorption data of the core sample; next, a first shale molecule dynamics model of the core sample is established, and a fitting adjustment is performed on the first shale molecule dynamics model using the shale gas adsorption data to obtain a second shale molecule dynamics model. Further, the second shale molecular dynamics model is used to obtain, by analogue simulation, shale gas adsorption data of the core sample corresponding to the various temperatures in a second-class pressure environment with high pressure, so as to obtain an accurate and comprehensive adsorption characteristic curve in a full pressure range.

A method and apparatus for determining content of adsorbed gas in a deep shale, and a server, wherein experimental tests are combined with molecular dynamics models. Firstly, tests are performed on a core sample of a target area at various temperatures in a first-class pressure environment with low pressure to obtain shale gas adsorption data of the core sample; next, a first shale molecule dynamics model of the core sample is established, and a fitting adjustment is performed on the first shale molecule dynamics model using the shale gas adsorption data to obtain a second shale molecule dynamics model. Further, the second shale molecular dynamics model is used to obtain, by analogue simulation, shale gas adsorption data of the core sample corresponding to the various temperatures in a second-class pressure environment with high pressure, so as to obtain an accurate and comprehensive adsorption characteristic curve in a full pressure range.

Apparatus, such as a portable oxygen concentrator (100) or other device communicating therewith, may be configured, such as with a processor(s), to estimate a remaining capacity of a sieve bed of the concentrator. Such apparatus may be configured to access a parameter of a measured pressure-time characteristic of the sieve bed for a phase of a pressure swing adsorption cycle of the oxygen concentrator. The apparatus may be configured to access function(s) of the parameter of the pressure-time characteristic and operational characteristic(s) of the sieve bed. The apparatus may be configured to estimate the remaining capacity by applying the function(s) to the parameter of the measured pressure-time characteristic. Such an estimate may then serve as a basis for providing notification, such as on a display or by electronic messaging, to inform of remaining life of the sieve bed, or otherwise promote timely replacement of a depleting component.

This disclosure is directed to systems and methods for assessing quality characteristics of food items based on analyzing volatiles outgassed by them. The quality characteristics can include presence of infection, ripeness stage, flavor, taste, and smell. Determining quality characteristics can be advantageous to make supply chain modifications that optimize on quality and reduce food-based waste. A tube having a sorbent material can be placed in an environment containing the food items. Volatiles outgassed by the food items can collect on the sorbent material. A computing system can receive the volatiles presence and concentration data and can apply a machine learning model to the data to determine quality characteristics of the food items. The model can be trained using human observations of quality characteristics, historic supply chain information, and processed volatiles data associated with other food items, wherein the other food items are a same type as the food items.

This disclosure is directed to systems and methods for assessing quality characteristics of food items based on analyzing volatiles outgassed by them. The quality characteristics can include presence of infection, ripeness stage, flavor, taste, and smell. Determining quality characteristics can be advantageous to make supply chain modifications that optimize on quality and reduce food-based waste. A tube having a sorbent material can be placed in an environment containing the food items. Volatiles outgassed by the food items can collect on the sorbent material. A computing system can receive the volatiles presence and concentration data and can apply a machine learning model to the data to determine quality characteristics of the food items. The model can be trained using human observations of quality characteristics, historic supply chain information, and processed volatiles data associated with other food items, wherein the other food items are a same type as the food items.

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.