An elongated apparatus that measures soil water tension is disclosed, having a hydrogel chamber for receiving a plurality of macro-sized hydrogel particles through its open side and a sealed inner wall, the hydrogel held in the hydrogel chamber by a durable, hydrophilic, and porous window secured to the open side of the hydrogel chamber. The window, when the apparatus is received in soil, transmits moisture between the soil and the hydrogel chamber, causing variable pressure within the hydrogel chamber that can be converted to a measurement of soil water tension on the opposite side of the window. This pressure produces various mechanical effects, measurable by various types of sensors within the elongated probe. A method for measuring soil water tension at multiple depths within a soil profile is also disclosed.

An elongated apparatus that measures soil water tension is disclosed, having a hydrogel chamber for receiving a plurality of macro-sized hydrogel particles through its open side and a sealed inner wall, the hydrogel held in the hydrogel chamber by a durable, hydrophilic, and porous window secured to the open side of the hydrogel chamber. The window, when the apparatus is received in soil, transmits moisture between the soil and the hydrogel chamber, causing variable pressure within the hydrogel chamber that can be converted to a measurement of soil water tension on the opposite side of the window. This pressure produces various mechanical effects, measurable by various types of sensors within the elongated probe. A method for measuring soil water tension at multiple depths within a soil profile is also disclosed.

In an example a pressure probe includes a tube having an output end, an internal passage, an axial run and pressure orifices axially aligned along a downstream side of the axial run. According to an aspect an upstream side of the axial run opposite from the downstream side of the axial run does not have a pressure orifice.

In an example a pressure probe includes a tube having an output end, an internal passage, an axial run and pressure orifices axially aligned along a downstream side of the axial run. According to an aspect an upstream side of the axial run opposite from the downstream side of the axial run does not have a pressure orifice.

Jet fuels' thermal oxidation characteristics are evaluated via the Standard Test Method for Thermal Stability of Aviation Turbine Fuels. This test method mimics the thermal stress conditions encountered by jet fuel in operation and is often carried out by laboratory devices, known as rigs. The rigs include a test section having a sleeve and a heater tube arranged therein. A pair of bus bars secure the test section to the rig and apply a current to the heater tube. The applied current heats the heater tube and subjects the sample jet fuels that are flowing in the volume between the sleeve and heater tube to high temperatures, which may produce thermal oxidation deposits on the heater tube. Heater tubes are difficult to install, however, and a gauge may be used to ensure accurate placement of the heater tube within the sleeve. In addition, the fuel sample must be prepared via an aeration process, and systems are disclosed for automating the aeration process such that the sample is prepared precisely according to the test standard. Moreover, the rig includes a pump system that moves the fuel sample through the test section, and a pump system is provided in a double syringe arrangement that optimizes fuel flow through the test section without fluctuation. Finally, the rigs include cooling systems for cooling the bus bars and maintaining an appropriate thermal profile within the heater tube, and cooling systems may be provided that independently control the temperature of each bus bar.

Jet fuels' thermal oxidation characteristics are evaluated via the Standard Test Method for Thermal Stability of Aviation Turbine Fuels. This test method mimics the thermal stress conditions encountered by jet fuel in operation and is often carried out by laboratory devices, known as rigs. The rigs include a test section having a sleeve and a heater tube arranged therein. A pair of bus bars secure the test section to the rig and apply a current to the heater tube. The applied current heats the heater tube and subjects the sample jet fuels that are flowing in the volume between the sleeve and heater tube to high temperatures, which may produce thermal oxidation deposits on the heater tube. Heater tubes are difficult to install, however, and a gauge may be used to ensure accurate placement of the heater tube within the sleeve. In addition, the fuel sample must be prepared via an aeration process, and systems are disclosed for automating the aeration process such that the sample is prepared precisely according to the test standard. Moreover, the rig includes a pump system that moves the fuel sample through the test section, and a pump system is provided in a double syringe arrangement that optimizes fuel flow through the test section without fluctuation. Finally, the rigs include cooling systems for cooling the bus bars and maintaining an appropriate thermal profile within the heater tube, and cooling systems may be provided that independently control the temperature of each bus bar.

The present disclosure provide a method and apparatus for pressure-pulse decay performed on whole cylindrical samples whose entire outer surface areas are eligible to receive the pulse. Using the methods and apparatus of the present disclosure, not only is the experimental time dramatically shortened, it also allows for simultaneous determination of local permeabilities parallel and perpendicular to their native bedding planes. Currently, there is no permeability-measurement technique to capable of doing so from a single sample from a single test.

The present disclosure provide a method and apparatus for pressure-pulse decay performed on whole cylindrical samples whose entire outer surface areas are eligible to receive the pulse. Using the methods and apparatus of the present disclosure, not only is the experimental time dramatically shortened, it also allows for simultaneous determination of local permeabilities parallel and perpendicular to their native bedding planes. Currently, there is no permeability-measurement technique to capable of doing so from a single sample from a single test.

A heat cover for a particulate matter sensor includes an aluminum foil external layer and an internal layer made from a composition including SiO.sub.2 of between 52-60%, CaO of between 16-25%, and Al.sub.2O.sub.2 of between 12-16%. The heat cover is formed as a sleeve structure and includes an open end for receiving the particulate matter sensor.

A heat cover for a particulate matter sensor includes an aluminum foil external layer and an internal layer made from a composition including SiO.sub.2 of between 52-60%, CaO of between 16-25%, and Al.sub.2O.sub.2 of between 12-16%. The heat cover is formed as a sleeve structure and includes an open end for receiving the particulate matter sensor.