19 Matching Annotations
1. Mar 2021
2. www.scienceintheclassroom.org www.scienceintheclassroom.org
1. triaxial accelerometer

A sensor that provides simultaneous measurements in three (x, y, and z) orthogonal directions. It analyzes vibrations caused by movement to infer orientation and acceleration of the device.

2. quasi-static tension

Quasi-static indicates that the acceleration effect on load measuring devices is insignificant, because it is moving extremely slowly.

3. elastomeric

A term describing the viscoelastic quality of a polymer. Materials that are elastomeric have weak intermolecular forces, low Young's modulus, and high failure strain.

4. self-healability

Chemically engineered materials have been integrated into the electronics that allow the device to self-repair even after multiple breaks.

This device utilizes a material called polyimine that repairs itself through bond exchange reactions.

5. reconfigurability

The ability to rearrange it's elements.

In this case, the device can be reconfigured to serve different purposes.

6. dynamic mechanical analyzer

A device used to study and characterize materials. A sinusoidal stress is applied to the material and the strain is measured. It is most effectively used to measure the viscoelastic behavior of polymers.

7. hyperelastic

Describes an ideally elastic material which the stress-strain relationship is derived from a strain energy density function. The stress does not vary linearly with strain, so it's flexibility is very high.

8. Poisson’s ratio

A measurement of the deformation in a material in a perpendicular direction to the applied force.

9. depolymerization

The process of converting a polymer into a monomer or monomers.

This process is triggered by an increase in thermal energy in the system that cannot be used (entropy).

10. Young’s modulus

In essence, this is a measurement of how stiff a material is.

It can be equated as E = stress / strain.

11. failure strain

A measure of how much a material can be elongated (strained) before it fails (breaks).

A measure of ~4% means it can be stretched to be about 4% longer before it breaks.

12. FEA

A method of numerically solving differential equations for mathematical modeling.

The problem is broken into smaller, finite elements that can be expressed as algebraic equations. These equations can then be assembled into a larger system of equations that models the entire problem.

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3. Feb 2021
4. www.scienceintheclassroom.org www.scienceintheclassroom.org
1. biocompatibility

The property of a material to be compatible with living tissue. Materials that trigger a toxic or immune response when exposed to the body are NOT biocompatible.

2. FTIR

One of the most common methods of spectroscopy. The sample is exposed to infrared light and data is collected to determine how much light is absorbed or released by the sample.

To convert the raw data into an actual spectrum, a Fourier transform must be performed.

3. thermoset polyimine matrix

Thermoset: applying heat to harden or cure the material. This creates the matrix encapsulating the device.

Thanks to the healing ability of the polyimine and the liquid nature of the eutectic LM circuitry, bonds can be reformed and reshaped throughout the device.

4. dynamic covalent

Upon thermosetting, dynamic covalent bonds are formed between the atoms that can readily assemble and disassemble. This gives the polyimines their unique healing ability.

5. ECG sensor

An electrocardiogram sensor records the pathway of electrical impulses throughout the heart. This data can be used to monitor the heart's condition and response to physical exertion.

6. transimination

A reaction that converts an -imine compound into smaller monomers/oligomers. The researchers discovered this reaction to be useful for separating the chip components and LM from the matrix by solubilizing the these monomers/oligomers in methanol.

7. eutectic LM

Eutectic: a mixture of substances that melts and solidifies totally at the same temperature, which is lower than the melting points of the individual constituents.

Eutectic LM: A mixture of liquid metals.