Liquid-gauging systems for estimating amounts of liquid within collapsible bladders. In some embodiments, a liquid-gauging system of this disclosure includes one or more liquid-gauging sensors that each output a signal relating to an amount of liquid within a corresponding collapsible bladder. In some embodiments, each liquid-gauging sensor comprises a variable capacitor having capacitor plates located so that the spacing between the capacitor plates changes with changing amounts of liquid within the collapsible bladder. In some embodiments, each liquid-gauging sensor comprises a pressure sensor for measuring forces, such as gravitational forces, that change with changing amounts of liquid within the collapsible bladder. In some embodiments, a liquid-gauging system is configured for an aircraft or other moving vehicle and includes one or more additional sensors to adjust the estimating process to account for changes in attitude of the vehicle during use. Corresponding methods, liquid-storage systems, and collapsible bladders are also disclosed.

A liquid product distribution network includes a liquid product distribution monitoring and reporting apparatus for operation in association with a tap handle flow monitoring and reporting apparatus. The liquid product distribution monitoring and reporting apparatus includes a radio transmitter device and sensing circuitry for sensing and communicating physical properties associating with the keg. A tap handle flow monitoring and reporting apparatus senses flow of a liquid through a tap includes a tap handle radio transmitter device for fitting within and protected by a tap handle and a low-energy consumption tap handle radio/processing module. A mobile communications device with geographic position sensing device and/or said tap handle flow monitoring and reporting apparatus passively and without user interaction within the liquid product distribution network, without using network uplink/gateway circuit devices for sensing and reporting fluid storage, flow, and financial operations relating to the distribution of said liquid product throughout the liquid product distribution network.

A liquid product distribution network includes a liquid product distribution monitoring and reporting apparatus for operation in association with a tap handle flow monitoring and reporting apparatus. The liquid product distribution monitoring and reporting apparatus includes a radio transmitter device and sensing circuitry for sensing and communicating physical properties associating with the keg. A tap handle flow monitoring and reporting apparatus senses flow of a liquid through a tap includes a tap handle radio transmitter device for fitting within and protected by a tap handle and a low-energy consumption tap handle radio/processing module. A mobile communications device with geographic position sensing device and/or said tap handle flow monitoring and reporting apparatus passively and without user interaction within the liquid product distribution network, without using network uplink/gateway circuit devices for sensing and reporting fluid storage, flow, and financial operations relating to the distribution of said liquid product throughout the liquid product distribution network.

Described is a method for determining a dwell volume of a liquid chromatography system and a liquid chromatography system that can determined the system dwell volume. The method includes mixing a flow of a first solvent with a flow of a second solvent to form a solvent mixture. The flows of the first and second solvents are decreased and increased, respectively, to generate a gradient composition. A system pressure of the liquid chromatography system is measured to determine a pressure trace defined as the measured system pressure as a function of time. The dwell volume of the system is determined from a time delay determined between the gradient composition at the mixing location and the pressure trace. The method can be performed with a liquid chromatography system having a chromatographic column or a flow restrictor used in place of the chromatographic column.

Described is a method for determining a dwell volume of a liquid chromatography system and a liquid chromatography system that can determined the system dwell volume. The method includes mixing a flow of a first solvent with a flow of a second solvent to form a solvent mixture. The flows of the first and second solvents are decreased and increased, respectively, to generate a gradient composition. A system pressure of the liquid chromatography system is measured to determine a pressure trace defined as the measured system pressure as a function of time. The dwell volume of the system is determined from a time delay determined between the gradient composition at the mixing location and the pressure trace. The method can be performed with a liquid chromatography system having a chromatographic column or a flow restrictor used in place of the chromatographic column.

A therapeutic gas source and cart and methods thereof for use with a therapeutic gas delivery system is disclosed. The therapeutic gas source may include a cylinder operable to contain a therapeutic gas that includes a body and a gas source valve body. In some examples, the gas source valve body has a valve and a coupling member.

A therapeutic gas source and cart and methods thereof for use with a therapeutic gas delivery system is disclosed. The therapeutic gas source may include a cylinder operable to contain a therapeutic gas that includes a body and a gas source valve body. In some examples, the gas source valve body has a valve and a coupling member.

A fluid device comprising a body with a membrane extending in a mean plane and showing an inner face and an outer face; a strain gauge arranged on the outer face of the membrane for measuring a deformation of the membrane when a fluid pressure is applied on the inner face thereof; wherein a bore is formed in the body, extending along an axis parallel to the mean plane of the membrane and delimiting a passage for the fluid under pressure, in fluid connection with the inner face of the membrane.

A system for precision liquid delivery includes a gas reservoir having a known volume. The system has a tightly load-coupled pneumatic driver (a “TLCP driver”) that is configured to receive input power to cause the TLCP driver to move gas into the gas reservoir to produce a gas drive pressure. A valve is configured to couple the gas reservoir with a fluid reservoir having an unknown volume. The valve is further configured to selectively isolate or pneumatically couple pressures in the gas reservoir and the fluid reservoir. A gas-fluid interface couples pressure in the fluid reservoir to pressure in a fluid path. The fluid path is configured so that the fluid drive pressure driving the liquid in the fluid path is substantially the same as the fluid reservoir pressure. The system also has a pressure sensor configured to detect pressure in the gas reservoir and/or the fluid reservoir.

A capacitive sensor including an electrically conductive material, and a single electrode applied with positive potential, wherein the distance between the single electrode and the electrically conductive material determines the spherical radius for a proximity sensing range.