Low-Cost Ultrasonic Frequency Inverter Using Single SCR

In this work, we excited as-spun wet films of PEDOT:PSS by ultrasonic vibration with varying frequency and power. This is a low-cost and facile technique for tailoring the structural and surface characteristics of solution-processed thin films and coatings. We deposited the coatings on both rigid and flexible substrates and performed various characterization techniques, such as atomic force microscopy (AFM), scanning electronic microscopy (SEM), X-ray photoelectron spectroscopy (XPS), attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), transmittance, electrical conductivity, and contact angle measurements, to understand how the ultrasonic vibration affects the coating properties. We found that as a result of ultrasonic vibration, PEDOT:PSS sheet conductivity increases up to five-fold, contact angle of water on PEDOT:PSS increases up to three-fold, and PEDOT:PSS roughness on glass substrates substantially decreases. Our results affirm that ultrasonic vibration can favor phase separation of PEDOT and PSS and rearrangement of PEDOT-rich charge transferring grains. In addition to providing a systematic study on the effect of ultrasonic frequency and power on the film properties, this work also proves that the ultrasonic vibration is a novel method to manipulate and tailor a wide range of properties of solution-processed thin films, such as compactness, chain length and arrangement of polymer molecules, conductivity, and surface wettability. This ultrasonication method can serve organic, printed and flexible electronics.

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SYNTHESIZING A WELL-ALIGNED CARBON NANOTUBE FOREST WITH HIGH QUALITY VIA THE NEBULIZED SPRAY PYROLYSIS METHOD BY OPTIMIZING ULTRASONIC FREQUENCY

NANO ◽

10.1142/s1793292011002640 ◽

2011 ◽

Vol 06 (04) ◽

pp. 343-348 ◽

Cited By ~ 4

Author(s):

ZHI YANG ◽

HUAGUI NIE ◽

XUEMEI ZHOU ◽

ZHEN YAO ◽

SHAOMING HUANG ◽

...

Keyword(s):

Spray Pyrolysis ◽

Large Scale ◽

Low Cost ◽

Spray Pyrolysis Method ◽

Ultrasonic Frequency ◽

High Quality ◽

Graphitization Degree ◽

Aligned Carbon Nanotubes ◽

Nebulized Spray Pyrolysis ◽

Process Method

Nebulized spray pyrolysis (NSP) offers ease of scaling into an industrial scale process method for large-scale CNT synthesis. In the method, ultrasonic frequency plays an important role in the formation of well-aligned carbon nanotubes (CNTs). In this work, we obtain well-aligned CNTs with high quality by optimizing ultrasonic frequency via the NSP method. SEM, TEM and HRTEM results show that the aligned CNTs obtained under an ultrasonic frequency of 1.8 MHz have good alignment, uniform nanotube length (~200 μm), high density and no trace of other carbon nanoparticles. The Raman spectra result further confirms that the aligned CNTs have a high graphitization degree. Furthermore, we find that ultrasonic frequency is an important factor in determining the nanotube diameter. The higher the ultrasonic frequency, the smaller the nanotube diameter. This rule may be very helpful in the preparation of large-scale well-aligned CNTs with high quality and diameter-controlled at low cost.

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Analysis and Implementation of a Low-cost High Frequency Inverter for Driving a Nonlinear Load

International Journal of Control and Automation ◽

10.14257/ijca.2015.8.2.19 ◽

2015 ◽

Vol 8 (2) ◽

pp. 187-196

Author(s):

Gang-Youl Jeong

Keyword(s):

High Frequency ◽

Low Cost ◽

Nonlinear Load ◽

Frequency Inverter

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Non-Destructive Evaluation Device for Monitoring Fluid Viscosity

Sensors ◽

10.3390/s20061657 ◽

2020 ◽

Vol 20 (6) ◽

pp. 1657

Author(s):

Ahmed Abdulkareem ◽

Ugur Erturun ◽

Karla Mossi

Keyword(s):

Wave Propagation ◽

Phase Shift ◽

Low Cost ◽

Response Analysis ◽

Ultrasonic Frequency ◽

Fluid Viscosity ◽

New Device ◽

Fluid Properties ◽

Harmonic Response Analysis ◽

Non Destructive

There is an increasing need for non-destructive, low-cost devices for real-time fluid viscosity monitoring. Therefore, in this study, a method based on structural health monitoring is adapted for monitoring fluid properties. A device is built such that an inexpensive and disposable viscosity probe be possible. The design incorporates a sensor/actuator pair using a piezoelectric material layered with copper/brass and capable of monitoring viscosity changes in low volume liquids (e.g., vacutainer vial). Experiments performed with the new device show a definite pattern of wave propagation in viscous solutions. A numerical model is built to investigate the wave propagation in the fluid. For experimental measurements, the sensor part of the device detects the generated pressure wave in fluid (e.g., air, water, glycerin) by the actuator part. The phase shift between the actuator and the sensor signals is then recorded and plotted for different concentrations of glycerin and water at room temperature. The results of this study show a direct correlation between the phase shift and varying viscosity in the ultrasonic frequency range from 6 to 9 MHz. The numerical simulation, performed utilizing acoustic modal and harmonic response analysis, results also demonstrate the same trend as the experimental results: a phase shift increases with the viscosity of the fluid.

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Decomposition of the metastable beta titanium alloy Ti-15-3

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075117 ◽

1983 ◽

Vol 41 ◽

pp. 264-265

Author(s):

Y. L. Chen ◽

S. Fujlshiro

Keyword(s):

Low Cost ◽

High Strength ◽

Alpha Phase ◽

Thick Sheet ◽

Omega Phase ◽

Beta Titanium Alloy ◽

Beta Titanium ◽

Beta Matrix ◽

Metastable Beta ◽

Very High

Metastable beta titanium alloys have been known to have numerous advantages such as cold formability, high strength, good fracture resistance, deep hardenability, and cost effectiveness. Very high strength is obtainable by precipitation of the hexagonal alpha phase in a bcc beta matrix in these alloys. Precipitation hardening in the metastable beta alloys may also result from the formation of transition phases such as omega phase. Ti-15-3 (Ti-15V- 3Cr-3Al-3Sn) has been developed recently by TIMET and USAF for low cost sheet metal applications. The purpose of the present study was to examine the aging characteristics in this alloy.The composition of the as-received material is: 14.7 V, 3.14 Cr, 3.05 Al, 2.26 Sn, and 0.145 Fe. The beta transus temperature as determined by optical metallographic method was about 770°C. Specimen coupons were prepared from a mill-annealed 1.2 mm thick sheet, and solution treated at 827°C for 2 hr in argon, then water quenched. Aging was also done in argon at temperatures ranging from 316 to 616°C for various times.

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Chromic Acid Etching of Polyethylene

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070801 ◽

1973 ◽

Vol 31 ◽

pp. 72-73

Author(s):

J. D. Muzzy ◽

R. D. Hester ◽

J. L. Hubbard

Keyword(s):

Chromic Acid ◽

Low Cost ◽

Acid Etching ◽

Crystalline Morphology ◽

Bulk Specimen ◽

Morphological Studies ◽

Perfect Form ◽

Molecular Length ◽

Lamellar Texture ◽

Cost Studies

Polyethylene is one of the most important plastics produced today because of its good physical properties, ease of fabrication and low cost. Studies to improve the properties of polyethylene are leading to an understanding of its crystalline morphology. Polyethylene crystallized by evaporation from dilute solutions consists of thin crystals called lamellae. The polyethylene molecules are parallel to the thickness of the lamellae and are folded since the thickness of the lamellae is much less than the molecular length. This lamellar texture persists in less perfect form in polyethylene crystallized from the melt.Morphological studies of melt crystallized polyethylene have been limited due to the difficulty of isolating the microstructure from the bulk specimen without destroying or deforming it.

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