Attribution analyses of reference evapotranspiration changes in China incorporating surface resistance change response to elevated CO2

It is difficult to monitor lightning damage to carbon fibre-reinforced polymers (CFRPs) online. This work experimentally investigates the changes associated with the electrical resistance of CFRPs subjected to lightning strikes. Two kinds of simulated lightning currents with different amplitudes in the range of 10–80 kA were injected into the CFRP samples. By measuring and comparing the changes in the struck-side (front) surface resistance, the surface resistance of the side opposite to the struck-side (back) and the oblique resistance of each sample before and after the lightning strike, it was observed that inflection points exist in the curve of the resistance change rate. The resistance decreases with increasing peak currents before the inflection point and increases when the peak current goes beyond the inflection point. The change rate of the front surface resistance is more sensitive to the lightning damage than are those of the back surface resistance and the oblique resistance. Different simulated lightning currents have approximately the same action integrals at the inflection points of resistance change rate. The characteristics indicate that resistance change detection could be a possible method for the online monitoring of CFRP lightning damage.

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Printed soft angular/torque sensors using carbon black-silicone composite

Sensor Review ◽

10.1108/sr-11-2018-0290 ◽

2019 ◽

Vol 39 (4) ◽

pp. 598-603 ◽

Cited By ~ 2

Author(s):

Muyang Li ◽

Mahtab Assadian ◽

Maziar Ramezani ◽

Kean C. Aw

Keyword(s):

Carbon Black ◽

Sensing Element ◽

Element Analysis ◽

Angular Rotation ◽

Output Resistance ◽

Resistance Change ◽

Turning Angle ◽

Content Type ◽

Extrusion Printing ◽

Change Response

Purpose This paper aims to propose the need for soft and flexible sensors that actually measure the turning angle and torque of a joint. Conventional rigid angular/torque sensors have compatibility issues in wearable applications due to its bulkiness, non-compliance and high rigidity. Design/methodology/approach The sensing element of the sensor is based on carbon black (CB)/Ecoflex composite, deposited via extrusion printing technique. A simple finite element analysis was used to explain the non-linearity and non-symmetricity behaviours of the sensor. Findings This prototype can measure the angular rotation up to ±180° and a maximum torque value of 0.6 Nm. The geometry of the printed CB/Ecoflex composite as piezoresistive trace has a significant effect on the output (resistance change) response. Originality/value This research explored an extrusion printing techniques that allow customization to construct a soft piezoresistive strain sensor, which can be used as an angular/torque sensor.

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