High-pressure intermittent

Nonoperative Nonpharmacological Intervention High-Pressure Intermittent Compression... 

In 2001, van Bemmelen and colleagues (90) published their longterm data using a high-pressure intermittent compression device for limb... 

Van Bemmelen PS, Gitlitz DB, Faruqi RM, et al. Limb salvage using high-pressure intermittent compression arterial assist device in cases unsuitable for surgical revascularization. Arch Surg 2001 136 1280-1285. 

The question of relative rates of seal leakage and permeation (cf. points 1 and 3) has been considered by MERE. For the sealing of HPHT (5000 psi, ca. 345 bar, or 34.5 MPa 100°C) fluids with chevron seal-stack systems used at the bottom of oil wells in intermittently dynamic conditions, high-pressure permeation and seal-leakage tests using the equipment outlined in Section 23.3.1.2 have been conducted it has been shown that methane gas permeation rate was only ca. 1 % of the rate... 

Plain-orifice atomizers are widely used for injecting liquids into a flow stream of air or gas. The injection may occur in a co-flow, a contra-flow, or a cross-flow stream. The best known application of plain-orifice atomizers is perhaps diesel injectors. This type of injectors is designed to provide a pulsed or intermittent supply of fuel to the combustion zone for each power stroke of the piston. As the air in the combustion zone is compressed by the piston to a high pressure, a very high pressure (83-103 MPa) is required to allow the fuel to penetrate into the combustion zone and disintegrate into a well-atomized spray. 

Other problems with pneumatic intensifier pumps include the fact that access to the high pressure seals for inspection and maintenance is usually quite restricted, by nature of their design. Because of the way they operate, the flow they produce is inherently highly pulsatile in nature and they also tend to be extremely noisy in use. For these reasons, pumps of this type are not used in general analytical HPLC. However, pneumatic intensifier pumps have found a niche in the packing of HPLC columns, where the intermittent nature of the function and their ability to deliver very high pressures compensate somewhat for their shortcomings in the analytical field. 

Bio-oils have so far mainly been in the focus as an alternative fuel for internal combustion engines. The fuel obtained from fast pyrolysis, however, displays properties which do not lend themselves easily to this application. Intermittent combustion under high pressure in an reciprocating machine appears more demanding than continuous combustion under lower pressure in the combustion chamber of a gas turbine. This is the working assumption for the studies repotted below. 

P9. Penrod, K. E., Effect of intermittent nitrogen exposures on tolerance to oxygen at high pressures. Am. J. Physiol. 186, 149-151 (1956). 

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