A microelectromechanical system for thermomechanical testing of nanostructures

2013 ◽  
Vol 103 (26) ◽  
pp. 263114 ◽  
Author(s):  
Tzu-Hsuan Chang ◽  
Yong Zhu
Keyword(s):  
Microelectromechanical System ◽  
Thermomechanical Testing

Modifiers for Rigid Polyvinylchloride Compositions of Building Purpose

2020 ◽  
Vol 787 (12) ◽  
pp. 34-39
Author(s):  
L.A. Abdrakhmanova ◽  
◽  
K.R. Khuziakhmetova ◽  
R.K. Nizamov ◽  
V.G. Khozin ◽  
...  
Keyword(s):  
Phase Interface ◽  
Thermomechanical Analysis ◽  
Favorable Effect ◽  
Heterogeneous Structure ◽  
Electron Microscopic ◽  
Wear And Tear ◽  
Thermomechanical Testing ◽  
Building Purpose ◽  
Microscopy Data ◽  
Butadiene Styrene

A comparison of small doses (up to 0.7 mass part) of impact strength modifiers of foreign and domestic production in polyvinylchloride-based compositions is given. Domestic acrylicnitrile- butadiene styrene modifiers (ABS) were used. The developed shock-resistant polyvinylchloride compositions in the presence of ABS elastifier have high melt fluidity, which has a beneficial effect on the recyclability. Changes in supramolecular structure were estimated from thermomechanical testing and electron microscopy data for both unfilled and filled PVC samples. Thermomechanical analysis showed that the presence of ABS modifier had a favorable effect on the technological properties of PVC-based samples. Electron-microscopic images indicate that in unfilled PVC samples, the heterogeneous PVC structure is expressed in the presence of ABS copolymer in comparison with foreign acrylic modifiers. When the compositions are filled with micro-heterogeneous structure in dispersion medium, the filler-polymer is formed by chalk particles, while ABS elasticifier is at the phase interface. Due to the peculiarities of the structure ABS has a higher degree of “fixation” on the surface of the chalk particles in comparison with the basic compositions containing acrylic modifiers, which with increasing chalk concentration leads to lower wear and tear on the top of the forming equipment.

scholarly journals A Novel 3D Printed Hollow Microneedle Microelectromechanical System for Controlled, Personalised Transdermal Drug Delivery

2020 ◽  
pp. 101815
Author(s):  
Sophia N. Economidou ◽  
Md. Jasim Uddin ◽  
Manuel J. Marques ◽  
Dennis Douroumis ◽  
Wan Ting Sow ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Transdermal Drug Delivery ◽  
Microelectromechanical System ◽  
Hollow Microneedle ◽  
3D Printed

scholarly journals Integrating Resonator to Enhance Magnetometer Microelectromechanical System Implementation with ASIC Compatible CMOS 0.18 μm Process

Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 635
Author(s):  
Chih-Hsuan Lin ◽  
Chao-Hung Song ◽  
Kuei-Ann Wen
Keyword(s):  
Resonant Frequency ◽  
Tuning Range ◽  
Dynamic Range ◽  
Ambient Pressure ◽  
Readout Circuit ◽  
Microelectromechanical System ◽  
Correlated Double Sampling ◽  
Driving Current ◽  
Mems Oscillator ◽  
Oscillation Characteristics

In this study, a multi-function microelectromechanical system (MEMS) was integrated with a MEMS oscillator, using the resonant frequency oscillation characteristics of the oscillator to provide the Lorentz current of the magnetometer to enhance a large dynamic range of reading, which eliminates the off-chip clock and current generator. The resonant frequency can be adjusted by adjusting the bias voltage of the oscillator to further adjust the sensitivity of the magnetometer. With the mechanical Q value characteristic, a great dynamic range can be achieved. In addition, using the readout circuit of the nested chopper and correlated double-sampling (CDS) to reduce the noise and achieve a smaller resolution, the calibration circuit compensates for errors caused by the manufacturing process. The frequency of the tuning range of the proposed structure is 17,720–19,924 Hz, and the tuning range of the measurement result is 110,620.36 ppm. The sensitivities of the x-, y-, and z-axes of the magnetometer with driving current of 2 mA are 218.3, 74.33, and 7.5 μV/μT for ambient pressure of 760 torr. The resolutions of the x-, y-, and z-axes of the magnetometer with driving current of 2 mA are 3.302, 9.69, and 96 nT/√Hz for ambient pressure of 760 torr.

scholarly journals Application of the MEMS Accelerometer as the Position Sensor in Linear Electrohydraulic Drive

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1479 ◽  
Author(s):  
Dominik Rybarczyk
Keyword(s):  
High Price ◽  
Second Phase ◽  
Position Sensor ◽  
Microelectromechanical System ◽  
Mems Accelerometer ◽  
Drive Control ◽  
Electrohydraulic Drive ◽  
Preliminary Research ◽  
Two Phases ◽  
Correction Phase

Various distance sensors are used as measuring elements for positioning linear electrohydraulic drives. The most common are magnetostrictive transducers or linear variable differential transformer (LVDT) sensors mounted inside the cylinder. The displacement of the actuator’s piston rod is proportional to the change in the value of the current or voltage at the output from the sensor. They are characterized by relatively low measurement noise. The disadvantage of presented sensors is the need to mount them inside the cylinders and the high price. The article presents preliminary research on the replacement of following sensors and the use of a microelectromechanical system (MEMS) accelerometer as a measuring element in the electrohydraulic drive control system. The control consisted of two phases: at first, the signal from the acceleration sensor was analyzed during the actuator movement, based on the value determined from the simplified model implemented on the controller. In the range of motion in which the dynamics were the lowest, the signal was integrated and the obtained value was used in the second phase of motion. In the correction phase, a new set point was determined. Conducting the research required building a dedicated research stand. The author conducted the simulation and experimental research.

Microactuator based on electroplated permanent magnets and flexible polydimethyl siloxane diaphragm

2008 ◽  
Vol 222 (3) ◽  
pp. 517-524 ◽  
Author(s):  
Y Su ◽  
H Wang ◽  
W Chen
Keyword(s):  
Permanent Magnets ◽  
Magnetic Energy ◽  
Optical Switch ◽  
Geometrical Parameters ◽  
Maximum Deflection ◽  
Polydimethyl Siloxane ◽  
Flexible Membrane ◽  
Microelectromechanical System ◽  
Planar Coil ◽  
A Current

The design, fabrication, and testing of a novel bidirectional magnetic microactuator were presented in the paper. The microactuator is composed of an integrated planar coil and a flexible polydimethyl siloxane (PDMS) diaphragm with embedded CoNiMnP-based permanent magnet arrays. There is a 7 × 7 array of magnets in a unit. The PDMS diaphragm is 2 mm × mm × 40 μm and the magnet post is 50 × 50 × 20 μm. Computer simulation was applied to verify the geometrical parameters. Electroplating under external magnetic field is carried out to improve the magnetic properties of the electroplated magnet, including coercivity, remanence and magnetic energy, and so on. The measured maximum coercivity, remanence and maximum magnetic energy were 2623 Oe (208.73 kA/m), 0.2 T (2000 G), and 10.15 kJ/m3 with the magnetic post, respectively. Moreover, and the deflection of the PDMS membrane is proportional to the exciting current. In a case of 0.35 A current, the maximum deflection of the membrane is 45 μm. Adjusting the electroplating mould results in the variation of the electroplated structure, thus the calibration of the microactuator. Due to the biomedical compatibility and simplicity of the fabrication, the flexible membrane-based microactuator is potential to be used as micropump and optical switch, the microelectromechanical system applications.

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