The purpose of this effort is to investigate whether large acoustic pressure waves can be transmitted inside beverage containers to enable pasteurization. Acoustic waves are known to induce large nonlinear compressive forces and shock waves in fluids, suggesting that compression waves may be capable of damaging bacteria inside beverage containers without appreciably increasingly the temperature or altering the freshness and flavor of the beverage contents. Although a combined process such as thermosonication (e.g., sonication with heating) is likely more efficient, it is instructive to compute the acoustic pressure field distribution inside the beverage container. The COMSOL simulations used two and three-dimensional models of beverage containers placed in a water bath to compute the acoustic pressure field. A limitation of these COMSOL models is that they cannot determine the bacterial lysis efficiency, rather the models provide an indirect metric of bacterial lysis based on the magnitude of the pressure field and its distribution.
Paldia, Robynne L.; Qia, Zhimin Q.; Misaa, Shikhar M.; Lua, Juanjuan L.; Suna, Xing S.; Phuaha, Xin L.; Branch, Darren W.; Siddiqui, Aleem M.; Wanga, Haiyan W.
Epitaxial lithium niobate (LNO) thin films are an attractive material for devices across a broad range of fields, including optics, acoustics, and electronics. These applications demand high-quality thin films without in-plane growth domains to reduce the optical/acoustical losses and optimize efficiency. Twin-free single-domain-like growth has been achieved previously, but it requires specific growth conditions that might be hard to replicate. In this work, a versatile nanocomposite-seeded approach is demonstrated as an effective approach to grow single-domain epitaxial lithium niobate thin films. Films are grown through a pulsed laser deposition method and growth conditions are optimized to achieve high-quality epitaxial film. A comprehensive microstructure characterization is performed and optical properties are measured. A piezoelectric acoustic resonator device is developed to demonstrate the future potential of the nanocomposite-seeded approach for high-quality LNO growth for radio frequency (RF) applications.
IFCS-ISAF 2020 - Joint Conference of the IEEE International Frequency Control Symposium and IEEE International Symposium on Applications of Ferroelectrics, Proceedings
A true series resonance oscillator has been developed for use with a wide-range of 1-port resonance-based sensors and devices. The oscillator effectively removes the shunt capacitance Co, allowing the true series resonance to be monitored, providing the optimum sensitivity across a wide range of frequencies (i.e. kilohertz to gigahertz), shunt capacitances, and quality factors (Q) for the first time. It is well-known that non-zero shunt capacitance alters the impedance by shifting the location of the impedance minimum and the zero-phase crossing while causing significant impedance distortion. We have developed an active shunt capacitance cancelling oscillator (ASSCO) that removes any shunt capacitance across the resonator by supplying the circuit an equal 'dummy' capacitance using a cancelling current. The oscillator does not require automatic gain control (AGC) and the resonator can be grounded to reduce parasitic contributions.
Miniature ultrasonic lysis for biological sample preparation is a promising technique for efficient and rapid extraction of nucleic acids and proteins from a wide variety of biological sources. Acoustic methods achieve rapid, unbiased, and efficacious disruption of cellular membranes while avoiding the use of harsh chemicals and enzymes, which interfere with detection assays. In this work, a miniature acoustic nucleic acid extraction system is presented. Using a miniature bulk acoustic wave (BAW) transducer array based on 36° Y-cut lithium niobate, acoustic waves were coupled into disposable laminate-based microfluidic cartridges. To verify the lysing effectiveness, the amount of liberated ATP and the cell viability were measured and compared to untreated samples. The relationship between input power, energy dose, flow-rate, and lysing efficiency were determined. DNA was purified on-chip using three approaches implemented in the cartridges: a silica-based sol-gel silica-bead filled microchannel, nucleic acid binding magnetic beads, and Nafion-coated electrodes. Using E. coli, the lysing dose defined as ATP released per joule was 2.2× greater, releasing 6.1× more ATP for the miniature BAW array compared to a bench-top acoustic lysis system. An electric field-based nucleic acid purification approach using Nafion films yielded an extraction efficiency of 69.2% in 10 min for 50 μL samples.
Branch, Darren W.; Smith, Gennifer T.; Vreeland, Erika C.; Blakemore, Robert; Alland, David
We have developed a miniature ultrasonic lysing system for the rapid release and extraction of Mycobacterium Tuberculosis (MTB) DNA. The prototype consists of two key sections, a disposable plastic manifold that hold sputum slides and a plastic cartridge with five fluidic DNA extraction channels. The MTB vaccine Bacillus Calmette-Guérin (BCG) was used as a simulant for MTB for all the lysing studies. The slide manifold houses up to five individual sputum slides and is processed by a computer to fill and load the cartridges with sputum suspensions from each slide. The plastic cartridge was developed to facilitate acoustic coupling through the bottom interface such that MTB/BCG can be lysed remotely. The disposable cartridge eliminated cross contamination problems and additional cleaning time. Due to the high power density, only 66 mW was required to lyse microliter BCG samples at the same level as the positive control (i.e. boiling for 30 minutes at 95 °C).
Eliminating spurious modes in Aluminum Nitride (AlN) microresonators improves their insertion loss and quality factor by reducing acoustic energy leakage. Spurious modes that result from transverse wave propagation, termed fine-frequency modes, leak energy and propagate in the electrical busing and appear near the fundamental resonance. Although these modes can be predicted using three-dimensional (3D) finite element methods (FEM) for devices with very short acoustic length (e.g. 1 acoustic wavelength), 3D FEM is very slow and memory intensive when compared to a two-dimensional (2D) simulation. A fast 2D coupling-of-modes (COM) model was developed to predict, identify and implement strategies to suppress the fine-frequency modes.
Bioweapons and emerging infectious diseases pose growing threats to our national security. Both natural disease outbreak and outbreaks due to a bioterrorist attack are a challenge to detect, taking days after the outbreak to identify since most outbreaks are only recognized through reportable diseases by health departments and reports of unusual diseases by clinicians. In recent decades, arthropod-borne viruses (arboviruses) have emerged as some of the most significant threats to human health. They emerge, often unexpectedly, from cryptic transmission foci causing localized outbreaks that can rapidly spread to multiple continents due to increased human travel and trade. Currently, diagnosis of acute infections requires amplification of viral nucleic acids, which can be costly, highly specific, technically challenging and time consuming. No diagnostic devices suitable for use at the bedside or in an outbreak setting currently exist. The original goals of this project were to 1) develop two highly sensitive and specific diagnostic assays for detecting RNA from a wide range of arboviruses; one based on an electrochemical approach and the other a fluorescent based assay and 2) develop prototype microfluidic diagnostic platforms for preclinical and field testing that utilize the assays developed in goal 1. We generated and characterized suitable primers for West Nile Virus RNA detection. Both optical and electrochemical transduction technologies were developed for DNA-RNA hybridization detection and were implemented in microfluidic diagnostic sensing platforms that were developed in this project.
This report describes X-cut lithium niobates (LiNbO3) utilization for voltage sensing by monitoring the acoustic wave propagation changes through LiNbO3 resulting from applied voltage. Direct current (DC), alternating current (AC) and pulsed voltage signals were applied to the crystal. Voltage induced shift in acoustic wave propagation time scaled quadratically for DC and AC voltages and linearly for pulsed voltages. The measured values ranged from 10 - 273 ps and 189 ps 2 ns for DC and non-DC voltages, respectively. Data suggests LiNbO3 has a frequency sensitive response to voltage. If voltage source error is eliminated through physical modeling from the uncertainty budget, the sensors U95 estimated combined uncertainty could decrease to ~0.025% for DC, AC, and pulsed voltage measurements.