Thermoplastic polyurethane flexible capacitive proximity sensor reinforced by CNTs for applications in the creative industries

AbstractWearable sensing platforms have been rapidly advanced over recent years, thanks to numerous achievements in a variety of sensor fabrication techniques. However, the development of a flexible proximity sensor that can perform in a large range of object mobility remains a challenge. Here, a polymer-based sensor that utilizes a nanostructure composite as the sensing element has been presented for forthcoming usage in healthcare and automotive applications. Thermoplastic Polyurethane (TPU)/Carbon Nanotubes (CNTs) composites are capable of detecting presence of an external object in a wide range of distance. The proximity sensor exhibits an unprecedented detection distance of 120 mm with a resolution of 0.3%/mm. The architecture and manufacturing procedures of TPU/CNTs sensor are straightforward and performance of the proximity sensor shows robustness to reproducibility as well as excellent electrical and mechanical flexibility under different bending radii and over hundreds of bending cycles with variation of 4.7% and 4.2%, respectively. Tunneling and fringing effects are addressed as the sensing mechanism to explain significant capacitance changes. Percolation threshold analysis of different TPU/CNT contents indicated that nanocomposites having 2 wt% carbon nanotubes are exhibiting excellent sensing capabilities to achieve maximum detection accuracy and least noise among others. Fringing capacitance effect of the structure has been systematically analyzed by ANSYS Maxwell (Ansoft) simulation, as the experiments precisely supports the sensitivity trend in simulation. Our results introduce a new mainstream platform to realize an ultrasensitive perception of objects, presenting a promising prototype for application in wearable proximity sensors for motion analysis and artificial electronic skin.

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The Multifunctional Composite on the Base of Carbon Nanotubes Network and its Use as a Passive Antenna and Gas Sensing Element

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.605.322 ◽

2014 ◽

Vol 605 ◽

pp. 322-325

Author(s):

Robert Olejnik ◽

Jiri Matyas ◽

Petr Slobodian ◽

Karel Vlcek

Keyword(s):

Carbon Nanotubes ◽

Gas Sensing ◽

Aqueous Suspension ◽

Multiwall Carbon Nanotubes ◽

Sensing Element ◽

Vapor Detection ◽

Filtration Method ◽

Wide Range ◽

Passive Antenna ◽

Nonpolar Organic

Carbon nanotubes in the form of entangled network can be used as a multifunctional composite material for a wide range of using. A new and perspective usage is a passive antenna and gas sensing element. The antenna works well at 1.284 GHz. The local reflection minimum is 11.48 dB. The reflection coefficient r=0.2667. The transmission power in this frequency is 93%. Multiwall carbon nanotubes (MWCNT) network Buckypaper was made by the vacuum filtration method of MWCNT aqueous suspension. The sensitivity of multi-wall carbon nanotube (MWCNT) networks of randomly entangled pure and HNO3 oxidized nanotubes to polar and nonpolar organic vapors (ethanol, heptane), has been investigated by resistance measurements. The results demonstrate that the network electrical resistance increases when exposed to organic solvent vapors, and a reversible reaction is observed when the sample is removed from the vapors. The investigated MWCNT networks could be potentially used as sensing elements for sensitive and selective organic vapor detection.

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Analysis of organic removal rates in the aerated submerged fixed film process

Water Science & Technology ◽

10.2166/wst.1998.0809 ◽

1998 ◽

Vol 38 (8-9) ◽

pp. 213-221 ◽

Cited By ~ 3

Author(s):

Mohamed F. Hamoda ◽

Ibrahim A. Al-Ghusain

Keyword(s):

Pilot Plant ◽

Removal Rate ◽

Domestic Wastewater ◽

Removal Rates ◽

Hydraulic Loading ◽

Organic Removal ◽

Wide Range ◽

Fixed Film ◽

Cod Removal Rate ◽

And Performance

Performance data from a pilot-plant employing the four-stage aerated submerged fixed film (ASFF) process treating domestic wastewater were analyzed to examine the organic removal rates. The process has shown high BOD removal efficiencies (> 90%) over a wide range of hydraulic loading rates (0.04 to 0.68 m3/m2·d). It could also cope with high hydraulic and organic loadings with minimal loss in efficiency due to the large amount of immobilized biomass attained. The organic (BOD and COD) removal rate was influenced by the hydraulic loadings applied, but organic removal rates of up to 104 kg BOD/ m2·d were obtained at a hydraulic loading rate of 0.68 m3/m2·d. A Semi-empirical model for the bio-oxidation of organics in the ASFF process has been formulated and rate constants were calculated based on statistical analysis of pilot-plant data. The relationships obtained are very useful for analyzing the design and performance of the ASFF process and a variety of attached growth processes.

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A New Method for Dispersing Pristine Carbon Nanotubes Using Regularly Arranged S-Layer Proteins

Nanomaterials ◽

10.3390/nano11051346 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1346

Author(s):

Andreas Breitwieser ◽

Uwe B. Sleytr ◽

Dietmar Pum

Keyword(s):

Carbon Nanotubes ◽

Covalent Modification ◽

Silica Layer ◽

Medical Sciences ◽

Lysinibacillus Sphaericus ◽

Wide Range ◽

Catalytic Sites ◽

Multi Walled Carbon Nanotubes ◽

Pristine Mwnts ◽

Walled Carbon Nanotubes

Homogeneous and stable dispersions of functionalized carbon nanotubes (CNTs) in aqueous solutions are imperative for a wide range of applications, especially in life and medical sciences. Various covalent and non-covalent approaches were published to separate the bundles into individual tubes. In this context, this work demonstrates the non-covalent modification and dispersion of pristine multi-walled carbon nanotubes (MWNTs) using two S-layer proteins, namely, SbpA from Lysinibacillus sphaericus CCM2177 and SbsB from Geobacillus stearothermophilus PV72/p2. Both the S-layer proteins coated the MWNTs completely. Furthermore, it was shown that SbpA can form caps at the ends of MWNTs. Reassembly experiments involving a mixture of both S-layer proteins in the same solution showed that the MWNTs were primarily coated with SbsB, whereas SbpA formed self-assembled layers. The dispersibility of the pristine nanotubes coated with SbpA was determined by zeta potential measurements (−24.4 +/− 0.6 mV, pH = 7). Finally, the SbpA-coated MWNTs were silicified with tetramethoxysilane (TMOS) using a mild biogenic approach. As expected, the thickness of the silica layer could be controlled by the reaction time and was 6.3 +/− 1.25 nm after 5 min and 25.0 +/− 5.9 nm after 15 min. Since S-layer proteins have already demonstrated their capability to bind (bio)molecules in dense packing or to act as catalytic sites in biomineralization processes, the successful coating of pristine MWNTs has great potential in the development of new materials, such as biosensor architectures.

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Road Characteristics Detection Based on Joint Convolutional Neural Networks with Adaptive Squares

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi10060377 ◽

2021 ◽

Vol 10 (6) ◽

pp. 377

Author(s):

Chiao-Ling Kuo ◽

Ming-Hua Tsai

Keyword(s):

Neural Networks ◽

Convolutional Neural Networks ◽

Autonomous Vehicles ◽

Detection Accuracy ◽

Geospatial Information ◽

Combination Rules ◽

And Performance ◽

Road Characteristics ◽

Machine Readable ◽

Background Image

The importance of road characteristics has been highlighted, as road characteristics are fundamental structures established to support many transportation-relevant services. However, there is still huge room for improvement in terms of types and performance of road characteristics detection. With the advantage of geographically tiled maps with high update rates, remarkable accessibility, and increasing availability, this paper proposes a novel simple deep-learning-based approach, namely joint convolutional neural networks (CNNs) adopting adaptive squares with combination rules to detect road characteristics from roadmap tiles. The proposed joint CNNs are responsible for the foreground and background image classification and various types of road characteristics classification from previous foreground images, raising detection accuracy. The adaptive squares with combination rules help efficiently focus road characteristics, augmenting the ability to detect them and provide optimal detection results. Five types of road characteristics—crossroads, T-junctions, Y-junctions, corners, and curves—are exploited, and experimental results demonstrate successful outcomes with outstanding performance in reality. The information of exploited road characteristics with location and type is, thus, converted from human-readable to machine-readable, the results will benefit many applications like feature point reminders, road condition reports, or alert detection for users, drivers, and even autonomous vehicles. We believe this approach will also enable a new path for object detection and geospatial information extraction from valuable map tiles.

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Fabrication and Compressive Behavior of a Micro-Lattice Composite by High Resolution DLP Stereolithography

Polymers ◽

10.3390/polym13050785 ◽

2021 ◽

Vol 13 (5) ◽

pp. 785

Author(s):

Chow Shing Shin ◽

Yu Chia Chang

Keyword(s):

High Resolution ◽

Lattice Structure ◽

Low Cost ◽

Hierarchical Structures ◽

Dip Coating ◽

Unit Cell ◽

Digital Light Processing ◽

Unit Cell Size ◽

Wide Range ◽

And Performance

Lattice structures are superior to stochastic foams in mechanical properties and are finding increasing applications. Their properties can be tailored in a wide range through adjusting the design and dimensions of the unit cell, changing the constituent materials as well as forming into hierarchical structures. In order to achieve more levels of hierarchy, the dimensions of the fundamental lattice have to be small enough. Although lattice size of several microns can be fabricated using the two-photon polymerization technique, sophisticated and costly equipment is required. To balance cost and performance, a low-cost high resolution micro-stereolithographic system has been developed in this work based on a commercial digital light processing (DLP) projector. Unit cell lengths as small as 100 μm have been successfully fabricated. Decreasing the unit cell size from 150 to 100 μm increased the compressive stiffness by 26%. Different pretreatments to facilitate the electroless plating of nickel on the lattice structure have been attempted. A pretreatment of dip coating in a graphene suspension is the most successful and increased the strength and stiffness by 5.3 and 3.6 times, respectively. Even a very light and incomplete nickel plating in the interior has increase the structural stiffness and strength by more than twofold.

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Effects of 3D Printing-Line Directions for Stretchable Sensor Performances

Materials ◽

10.3390/ma14071791 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1791

Author(s):

Chi Cuong Vu ◽

Thanh Tai Nguyen ◽

Sangun Kim ◽

Jooyong Kim

Keyword(s):

3D Printing ◽

Thermoplastic Polyurethane ◽

Three Dimensional ◽

Optimal Solution ◽

Human Motion ◽

Repeated Measurements ◽

Fused Filament Fabrication ◽

And Performance ◽

The Times ◽

Stretchable Sensors

Health monitoring sensors that are attached to clothing are a new trend of the times, especially stretchable sensors for human motion measurements or biological markers. However, price, durability, and performance always are major problems to be addressed and three-dimensional (3D) printing combined with conductive flexible materials (thermoplastic polyurethane) can be an optimal solution. Herein, we evaluate the effects of 3D printing-line directions (45°, 90°, 180°) on the sensor performances. Using fused filament fabrication (FDM) technology, the sensors are created with different print styles for specific purposes. We also discuss some main issues of the stretch sensors from Carbon Nanotube/Thermoplastic Polyurethane (CNT/TPU) and FDM. Our sensor achieves outstanding stability (10,000 cycles) and reliability, which are verified through repeated measurements. Its capability is demonstrated in a real application when detecting finger motion by a sensor-integrated into gloves. This paper is expected to bring contribution to the development of flexible conductive materials—based on 3D printing.

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BSAS Ethical Policy British Society of Animal Science Ethical guidelines for research in animal science

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200011571 ◽

2005 ◽

Vol 2005 ◽

pp. 247-253 ◽

Cited By ~ 1

Author(s):

S. Jarvis ◽

J.E.L. Day ◽

B. Reed

Keyword(s):

Ethical Issues ◽

Science Research ◽

British Society ◽

Ethical Guidelines ◽

Animal Science ◽

Ethical Implications ◽

Ethical Policy ◽

Physical Environments ◽

Wide Range ◽

And Performance

Animal science research is important in relation to our understanding of animals, their function and performance, and their relationships with their social and physical environments. Animal science research covers a wide range of disciplines and so can lead to the use of a variety of experimental techniques on animals for many different purposes. This has the potential to lead to a multitude of diverse ethical issues. Members of the British Society of Animal Science and authors of papers submitted to the Society for publication come from countries around the world and therefore are subject to differences in legislative requirements and recommendations regarding animal experimentation. These legal requirements, along with the ethical implications of the research must be fully considered before any experimental work is undertaken.

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CFD Study of Nozzle Configurations for Ultra High Bypass Engines

Volume 3C: General ◽

10.1115/93-gt-389 ◽

1993 ◽

Cited By ~ 1

Author(s):

H. Zimmermann ◽

R. Gumucio ◽

K. Katheder ◽

A. Jula

Keyword(s):

Engine Performance ◽

Operating Conditions ◽

Aerodynamic Design ◽

Thrust Coefficient ◽

Optimum Range ◽

Installation Effects ◽

Wide Range ◽

And Performance ◽

Aircraft Aerodynamics ◽

Bypass Ratio

Performance and aerodynamic aspects of ultra-high bypass ratio ducted engines have been investigated with an emphasis on nozzle aerodynamics. The interference with aircraft aerodynamics could not be covered. Numerical methods were used for aerodynamic investigations of geometrically different aft end configurations for bypass ratios between 12 and 18, this is the optimum range for long missions which will be important for future civil engine applications. Results are presented for a wide range of operating conditions and effects on engine performance are discussed. The limitations for higher bypass ratios than 12 to 18 do not come from nozzle aerodynamics but from installation effects. It is shown that using CFD and performance calculations an improved aerodynamic design can be achieved. Based on existing correlations, for thrust and mass-flow, or using aerodynamic tailoring by CFD and including performance investigations, it is possible to increase the thrust coefficient up to 1%.

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Design, implementation, and evaluation of an XG-PON module for the ns-3 network simulator

SIMULATION ◽

10.1177/0037549716682093 ◽

2017 ◽

Vol 93 (5) ◽

pp. 409-426 ◽

Cited By ~ 5

Author(s):

Jerome A Arokkiam ◽

Pedro Alvarez ◽

Xiuchao Wu ◽

Kenneth N Brown ◽

Cormac J Sreenan ◽

...

Keyword(s):

Optical Network ◽

Future Internet ◽

Access Networks ◽

Passive Optical Network ◽

Network Simulator ◽

Optical Access Networks ◽

Research Topics ◽

Extensive Evaluation ◽

Wide Range ◽

And Performance

10-gigabit-capable Passive Optical Network (XG-PON), one of the latest standards of optical access networks, is regarded as one of the key technologies for future Internet access networks. This paper presents the design and evaluation of our XG-PON module for the ns-3 network simulator. This module is designed and implemented with the aim to provide a standards-compliant, configurable, and extensible module that can simulate XG-PON with reasonable speed and support a wide range of research topics. These include analyzing and improving the performance of XG-PON, studying the interactions between XG-PON and the upper-layer protocols, and investigating its integration with various wireless networks. In this paper, we discuss its design principles, describe the implementation details, and present an extensive evaluation on both functionality and performance.

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Metal Organic Frameworks Derived Fe-N-C Nanostructures as High-Performance Electrodes for Sodium Ion Batteries and Electromagnetic Interference (EMI) Shielding

Molecules ◽

10.3390/molecules26041018 ◽

2021 ◽

Vol 26 (4) ◽

pp. 1018

Author(s):

Vadahanambi Sridhar ◽

Inwon Lee ◽

Hyun Park

Keyword(s):

Carbon Nanotubes ◽

Graphene Oxide ◽

Electromagnetic Interference ◽

Sodium Ion ◽

Iron Nitride ◽

Sodium Ion Batteries ◽

Nitrogen Doped ◽

Wide Range ◽

Metal Organic ◽

Nitrogen Doped Carbon

Metal organic framework (MOF)-derived carbon nanostructures (MDC) synthesized by either calcinations or carbonization or pyrolysis are emerging as attractive materials for a wide range of applications like batteries, super-capacitors, sensors, water treatment, etc. But the process of transformation of MOFs into MDCs is time-consuming, with reactions requiring inert atmospheres and reaction time typically running into hours. In this manuscript, we report the transformation of 1,4-diazabicyclo[2.2.2]octane, (DABCO)-based MOFs into iron nitride nanoparticles embedded in nitrogen-doped carbon nanotubes by simple, fast and facile microwave pyrolysis. By using graphene oxide and carbon fiber as microwave susceptible surfaces, three-dimensional nitrogen-doped carbon nanotubes vertically grown on reduced graphene oxide (MDNCNT@rGO) and carbon fibers (MDCNT@CF), respectively, were obtained, whose utility as anode material in sodium-ion batteries (MDNCNT@rGO) and for EMI (electromagnetic interference) shielding material (MDCNT@CF) is reported.

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