Low-pressure-sensitive baroreceptor fibers recorded from rabbit carotid sinus nerves.

Low-pressure-sensitive composites using multi-walled carbon nanotubes as a conductive filler and poly(dimethylsiloxane) as a polymer matrix have been fabricated, and their electrical and piezoresistive properties have been studied. A large aspect ratio of the MWCNTs was used to achieve good electrical properties of the composite, which led to a significant decrease in the percolation threshold and an increase in the electrical conductivity for very low MWCNT loadings. The piezoresistive properties of the composites at < 1.2 MPa were studied, which showed that the resistance–pressure sensitivity of the composites could be modulated by varying the MWCNT loading in the PDMS matrix.

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Effect of Oxygen Mole Fraction on Static Properties of Pressure-Sensitive Paint

Sensors ◽

10.3390/s21041062 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1062

Author(s):

Tomohiro Okudera ◽

Takayuki Nagata ◽

Miku Kasai ◽

Yuji Saito ◽

Taku Nonomura ◽

...

Keyword(s):

Partial Pressure ◽

Mole Fraction ◽

Ambient Pressure ◽

Low Pressure ◽

Pressure Sensitive Paint ◽

Partial Pressure Of Oxygen ◽

Static Properties ◽

Pressure Sensitive ◽

High Partial Pressure ◽

Oxygen Mole Fraction

The effects of the oxygen mole fraction on the static properties of pressure-sensitive paint (PSP) were investigated. Sample coupon tests using a calibration chamber were conducted for poly(hexafluoroisopropyl methacrylate)-based PSP (PHFIPM-PSP), polymer/ceramic PSP (PC-PSP), and anodized aluminum PSP (AA-PSP). The oxygen mole fraction was set to 0.1–100%, and the ambient pressure (Pref) was set to 0.5–140 kPa. Localized Stern–Volmer coefficient Blocal increased and then decreased with increasing oxygen mole fraction. Although Blocal depends on both ambient pressure and the oxygen mole fraction, its effect can be characterized as a function of the partial pressure of oxygen. For AA-PSP and PHFIPM-PSP, which are low-pressure- and relatively low-pressure-type PSPs, respectively, Blocal peaks at PO2ref<12 kPa. In contrast, for PC-PSP, which is an atmospheric-pressure-type PSP in the investigated range, Blocal does not have a peak. Blocal has a peak at a relatively high partial pressure of oxygen due to the oxygen permeability of the polymer used in the binder. The peak of SPR, which is the emission intensity change with respect to normalized pressure fluctuation, appears at a lower partial pressure of oxygen than that of Blocal. This is because the intensity of PSP becomes quite low at a high partial pressure of oxygen even if Blocal is high. Hence, the optimal oxygen mole fraction depends on the type of PSP and the ambient pressure range of the experiment. This optimal value can be found on the basis of the partial pressure of oxygen.

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Research of pressure sensitive paint using lifetime based method for low pressure flow field

The Proceedings of the Fluids engineering conference ◽

10.1299/jsmefed.2016.1307 ◽

2016 ◽

Vol 2016 (0) ◽

pp. 1307

Author(s):

Kil-Ju MOON

Keyword(s):

Flow Field ◽

Low Pressure ◽

Pressure Sensitive Paint ◽

Pressure Flow ◽

Pressure Sensitive

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Effects of Electrical Discharges in Low Pressure Gases on the Morphology of Polyethylene Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052730 ◽

1974 ◽

Vol 32 ◽

pp. 544-545

Author(s):

L.H. Bolz ◽

D.H. Reneker

Keyword(s):

Power Distribution ◽

Electrical Discharge ◽

Dielectric Breakdown ◽

Ionic Species ◽

Low Pressure ◽

Polymer Surfaces ◽

Electrical Discharges ◽

Adhesive Bonds ◽

Power Distribution Lines ◽

Modification Of The Surface

The attack, on the surface of a polymer, by the atomic, molecular and ionic species that are created in a low pressure electrical discharge in a gas is interesting because: 1) significant interior morphological features may be revealed, 2) dielectric breakdown of polymeric insulation on high voltage power distribution lines involves the attack on the polymer of such species created in a corona discharge, 3) adhesive bonds formed between polymer surfaces subjected to such SDecies are much stronger than bonds between untreated surfaces, 4) the chemical modification of the surface creates a reactive surface to which a thin layer of another polymer may be bonded by glow discharge polymerization.

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Field ion microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104236 ◽

1988 ◽

Vol 46 ◽

pp. 434-435

Author(s):

Gert Ehrlich

Keyword(s):

Low Temperature ◽

Sample Surface ◽

Low Pressure ◽

Radius Of Curvature ◽

Field Ion Microscopy ◽

Phosphor Screen ◽

Ion Microscopy ◽

Field Ion Microscope

The field ion microscope, devised by Erwin Muller in the 1950's, was the first instrument to depict the structure of surfaces in atomic detail. An FIM image of a (111) plane of tungsten (Fig.l) is typical of what can be done by this microscope: for this small plane, every atom, at a separation of 4.48Å from its neighbors in the plane, is revealed. The image of the plane is highly enlarged, as it is projected on a phosphor screen with a radius of curvature more than a million times that of the sample. Müller achieved the resolution necessary to reveal individual atoms by imaging with ions, accommodated to the object at a low temperature. The ions are created at the sample surface by ionization of an inert image gas (usually helium), present at a low pressure (< 1 mTorr). at fields on the order of 4V/Å.

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