We report an experimental measurement of the acoustic signal emitted from an individual suspended carbon nanotube (CNT) approximate 2 μm in length, 1 nm in diameter, and 10(-21) kg in mass. This system represents the smallest thermoacoustic system studied to date. By applying an AC voltage of 1.4 V at 8 kHz to the suspended CNT, we are able to detect the acoustic signal using a commercial micro...

How to deal with and use of electricity efficiently from the thermoacoustic power generation system, including the rectifier, inverter, storage, are another question faced with. The reason was analyzed based on thermal acoustic instability and the oscillation amplitude difference. The idea was put forward how to solve thermoacoustic wave instability or oscillatory amplitude difference. If power...

Scanning thermoacoustic tomography was explored in the microwave region of the electromagnetic spectrum. Short microwave pulses were used to induce acoustic waves by thermoelastic expansion in biological tissues. Cross sections of tissue samples were imaged by a linear scan of the samples while a focused ultrasonic transducer detected the time-resolved thermoacoustic signals. Based on the micro...

We have developed a novel carbon nanotube-based contrast agent for both thermoacoustic and photoacoustic tomography. In comparison to deionized water, single-walled carbon nanotubes exhibited more than twofold signal enhancement for thermoacoustic tomography at 3 GHz. In comparison to blood, they exhibited more than sixfold signal enhancement for photoacoustic tomography at 1064 nm wavelength. ...

A fast thermoacoustic computed tomography system with a multielement linear transducer array was developed to image biological tissues with circular scanning. The spatial resolution of the imaging system and the spectra of the thermoacoustic signals were analyzed. A modified integration backprojection algorithm using velocity potential was employed to recover the direct energy deposition distri...

Thermoacoustic heat engines (TAEs) are potentially advantageous drivers for thermoacoustic refrigerators (TARs). Connecting TAEs to TARs means that waste heat can effectively be utilized to provide cooling, and increase overall efficiency. However, this is currently a niche technology. Improvements can be made through a better understanding of the interactions of relevant design parameters. Thi...

The endogenous contrast in thermoacoustic imaging is due to the water and ionic content in tissue. This results in poor tissue specificity between high water content tissues. As a result, exogenous contrast agents have been employed to improve tissue specificity and also increase the SNR. An investigation into the sources of contrast produced by several exogenous contrast agents is described. T...

Microwave-induced thermoacoustic tomography was explored to image biological tissue. Short microwave pulses irradiated tissue to generate acoustic waves by thermoelastic expansion. The microwave-induced thermoacoustic waves were detected with a focused ultrasonic transducer. Each time-domain signal from the ultrasonic transducer represented a one-dimensional image along the acoustic axis of the...

This paper presents a cost-effective method to increase the COP and utility of a domestic refrigerator using R-134a refrigerant. A cabin was installed on the top of a domestic refrigerator with condenser coils of refrigerator serving as heating coils inside the cabin. Known quantity of water was heated by the condenser coils (due to convection currents) thereby increasing the overall COP of the...