We used a capacitive technique to determine the radial clearance between the piston and cylinder of a gas piston gauge. This method determines the effective area of a piston gauge pressure standard, independent of calibration against another piston gauge or manometer, as long as the diameter of the piston is dimensionally measured. It also allows an independent determination of piston gauge dis...

A liquid piston concept is proposed to improve the efficiency of gas compression and expansion. Because a liquid can conform to an irregular chamber volume, the surface area to volume ratio in the gas chamber can be maximized using a liquid piston. This creates near-isothermal operation, which minimizes energy lost to heat generation. A liquid piston eliminates gas leakage and replaces sliding ...

We consider a heavy piston in an infinite cylinder surrounded by ideal gases on both sides. The piston moves under elastic collisions with gas atoms. We assume here that the gases always exert equal pressures on the piston, hence the piston remains at the so called mechanical equilibrium. However, the temperatures and densities of the gases may differ across the piston. In that case some earlie...

Pumps are often used in both industrial applications and mobile hydraulic machinery. In variable displacement pumps, the flow rate is dictated by the system requirements. The electro-hydraulic pump is a new integrated product, which comprise the combination of a pump and motor as a unit replacing the traditional connection with a shaft coupling. The pump is actuated without a rotating shaft uti...

By theoretically analyzing dynamic behavior of the crankshaft, the rolling piston and the blade inrolling-piston rotary compressors, constraint forces and sliding speed at each pair of movable machine elements were obtained, and unbalanced inertia forces and compressor vibrations were evaluated. It was concluded that theoretical results have a goodagreement with experimental ones. Moreover, it ...

This scientific commentary refers to “Key questions for the evaluation of anti-amyloid immunotherapies Alzheimer”s disease', by Liu et al. (https://doi.org/10.1093/braincomms/fcad175)

plants available. For this reason we have found that Teflon provides the most effective decompression because of its pliability. If compression by the implant is the proposed cause of recurrence, why is the recurrence rate so low? Drs. Ryu and Yamamoto propose an interesting alternative technique for performing microvascular decompression by coapting the vascular loop to the dura with the use o...

In this work, a generalized expression of the photoacoustic ~PA! effect in a multilayer material is derived. This expression takes thermal and optical properties and geometry of a multilayer structure, as well as the thermal contact resistances between layers into consideration. In addition, a composite piston model consisting of a thermal piston and a mechanical piston of the PA effect is deve...

In preparing of thermoluminescent dosimeters (TLD) it is common to use as agglutinator the polytetrafluoroethylene (PTFE), called Teflon. In this paper the physical, morphological and dosimetric characteristics of Teflon were evaluated aiming its application in thermoluminescent dosimetry. The differential thermal analysis (DTA) and thermogravimetry (TG) results showed that the Teflon glass tra...