Magnetic Properties of Ferromagnetic Particles under Alternating Magnetic Fields: Focus on Particle Detection Sensor Applications

The electromagnetic wear particles detection sensor has been widely studied due to its ability to monitor the wear status of equipment in real time. To precisely estimate the change of the magnetic energy of the sensor coil caused by the wear particles, the magnetic property models of wear particles under the alternating magnetic field was established. The models consider the hysteresis effect and the eddy current effect of the wear particles. The analysis and experimental results show that with the increase of the effective field frequency, the change of the magnetic energy caused by the wear particles gradually decrease, which makes the induced electromotive force output by the sensor reduce with the decrease of the particle speed, so a signal compensation method is presented to obtain a unified signal when the same wear particle passing through the sensor in different speeds. The magnetic coupling effect between the two adjacent wear particles is analyzed. The result illustrates that the change of the magnetic energy caused by the dual wear particles system is larger than the sum of the energy variation caused by two independent wear particles, and with the increase of the interparticle distance, the magnetic coupling effect gradually weakens and disappears.

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Dynamic Response of Spiral Cantilever Undergoing Magnetic Coupling

International Journal of Structural Stability and Dynamics ◽

10.1142/s0219455414400215 ◽

2014 ◽

Vol 14 (08) ◽

pp. 1440021

Author(s):

Xiaoling Bai ◽

Yumei Wen ◽

Ping Li ◽

Jin Yang ◽

Xiao Peng ◽

...

Keyword(s):

Dynamic Response ◽

Cantilever Beam ◽

Magnetic Force ◽

Coupling Effect ◽

Magnetic Coupling ◽

Resonant Frequencies ◽

Energy Harvesters ◽

Magnetic Transducer ◽

Underlying Mechanisms ◽

Tip Mass

Cantilever beams have found intensive and extensive uses as underlying mechanisms for energy transduction in sensors as well as in energy harvesters. In magnetoelectric (ME) transduction, the underlying cantilever beam usually will undergo magnetic coupling effect. As the beam itself is either banded with magnetic transducer or magnets, the dynamic motion of the cantilever can be modified due to the magnetic force between the magnets and ME sensors. In this study, the dynamic response of a typical spiral cantilever beam with magnetic coupling is investigated. The spiral cantilever acts as the resonator of an energy harvester with a tip mass in the form of magnets, and a ME transducer is positioned in the air gap and interacts with the magnets. It is expected that this spiral configuration is capable of performing multiple vibration modes over a small frequency range and the response frequencies can be magnetically tunable. The experimental results show that the magnetic coupling between the magnets and the transducer plays a favorable role in achieving tunable resonant frequencies and reducing the frequency spacings. This will benefits the expansion of the response band of a device and is especially useful in energy harvesting.

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Brake Wear Particle Size and Shape Analysis of Non-Asbestos Organic (NAO) and Semi Metallic Brake Pad

Jurnal Teknologi ◽

10.11113/jt.v71.3731 ◽

2014 ◽

Vol 71 (2) ◽

Author(s):

Hussain, S. ◽

M.K Abdul Hamid ◽

A.R Mat Lazim ◽

A.R. Abu Bakar

Keyword(s):

Particle Size ◽

Wear Particle ◽

Brake Disc ◽

Wear Particles ◽

Brake Pad ◽

Brake Pads ◽

Size And Shape ◽

Brake Wear Particles ◽

Brake Wear ◽

Particle Size And Shape

Brake wear particles resulting from friction between the brake pad and disc are common in brake system. In this work brake wear particles were analyzed based on the size and shape to investigate the effects of speed and load applied to the generation of brake wear particles. Scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDX) was used to identify the size, shape and element compositions of these particles. Two types of brake pads were studied which are non-asbestos organic and semi metallic brake pads. Results showed that the size and shape of the particles generatedvary significantly depending on the applied brake load, and less significantly on brake disc speed. The wear particle becomes bigger with increasing applied brake pressure. The wear particle size varies from 300 nm to 600 µm, and contained elements such as carbon, oxygen, magnesium, aluminum, sulfur and iron.

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Novel biological strategies for treatment of wear particle-induced periprosthetic osteolysis of orthopaedic implants for joint replacement

Journal of The Royal Society Interface ◽

10.1098/rsif.2013.0962 ◽

2014 ◽

Vol 11 (93) ◽

pp. 20130962 ◽

Cited By ~ 76

Author(s):

S. B. Goodman ◽

E. Gibon ◽

J. Pajarinen ◽

T.-H. Lin ◽

M. Keeney ◽

...

Keyword(s):

Pathologic Fracture ◽

Wear Particle ◽

Wear Particles ◽

Implant Loosening ◽

Orthopaedic Implants ◽

Periprosthetic Osteolysis ◽

Joint Replacements ◽

Local Inhibition ◽

Tissue Healing ◽

Chronic Inflammatory Reaction

Wear particles and by-products from joint replacements and other orthopaedic implants may result in a local chronic inflammatory and foreign body reaction. This may lead to persistent synovitis resulting in joint pain and swelling, periprosthetic osteolysis, implant loosening and pathologic fracture. Strategies to modulate the adverse effects of wear debris may improve the function and longevity of joint replacements and other orthopaedic implants, potentially delaying or avoiding complex revision surgical procedures. Three novel biological strategies to mitigate the chronic inflammatory reaction to orthopaedic wear particles are reported. These include (i) interference with systemic macrophage trafficking to the local implant site, (ii) modulation of macrophages from an M1 (pro-inflammatory) to an M2 (anti-inflammatory, pro-tissue healing) phenotype in the periprosthetic tissues, and (iii) local inhibition of the transcription factor nuclear factor kappa B (NF-κB) by delivery of an NF-κB decoy oligodeoxynucleotide, thereby interfering with the production of pro-inflammatory mediators. These three approaches have been shown to be viable strategies for mitigating the undesirable effects of wear particles in preclinical studies. Targeted local delivery of specific biologics may potentially extend the lifetime of orthopaedic implants.

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A piezoelectric energy harvester based on magnetic coupling effect

Manufacturing Engineering and Intelligent Materials ◽

10.1201/b18620-9 ◽

2015 ◽

pp. 53-58

Keyword(s):

Energy Harvester ◽

Coupling Effect ◽

Magnetic Coupling ◽

Piezoelectric Energy

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A simple method of suspending implant wear particles for more physiological modelling of cell-particle interactions in vitro

10.1101/2021.01.05.425343 ◽

2021 ◽

Author(s):

Christine Poon

Keyword(s):

Wear Debris ◽

Culture Media ◽

Polymeric Materials ◽

Wear Particle ◽

Physicochemical Characteristics ◽

Wear Particles ◽

Simple Method ◽

Implant Wear

AbstractArthroplasty implants e.g. hip, knee, spinal disc sustain relatively high compressive loading and friction wear, which lead to the formation of wear particles or debris between articulating surfaces. Despite advances in orthopaedic materials and surface treatments, the production of wear debris from any part of a joint arthroplasty implant is currently unavoidable. Implant wear debris induces host immune responses and inflammation, which causes patient pain and ultimately implant failure through progressive inflammation-mediated osteolysis and implant loosening, where the severity and rate of periprosthetic osteolysis depends on the material and physicochemical characteristics of the wear particles. Evaluating the cytotoxicity of implant wear particles is important for regulatory approved clinical application of arthroplasty implants, as is the study of cell-particle response pathways. However, the wear particles of polymeric materials commonly used for arthroplasty implants tend to float when placed in culture media, which limits their contact with cell cultures. This study reports a simple means of suspending wear particles in liquid medium using sodium carboxymethyl cellulose (NaCMC) to provide a more realistic proxy of the interaction between cells and tissues to wear particles in vivo, which are free-floating in synovial fluid within the joint cavity. Low concentrations of NaCMC dissolved in culture medium were found to be effective for suspending polymeric wear particles. Such suspensions may be used as more physiologically-relevant means for testing cellular responses to implant wear debris, as well as studying the combinative effects of shear and wear particle abrasion on cells in a dynamic culture environments such as perfused tissue-on-chip devices.

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Classification of Wear Debris Using Weighted Fuzzy Cluster Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.33.70 ◽

2010 ◽

Vol 33 ◽

pp. 70-73

Author(s):

Dai Qiang Peng ◽

Feng Xu

Keyword(s):

Wear Debris ◽

Wear Particle ◽

Fuzzy Cluster ◽

Cluster Method ◽

Wear Particles ◽

Machine Condition ◽

Machine Condition Monitoring ◽

Fuzzy Cluster Method ◽

The Membership Function

The analysis and identification of wear particles for machine condition monitoring is usually very time-consuming by experienced inspectors. In order to remedy the limitation, automation of the analysis procedure appears to be necessary. A novel weighted fuzzy c-means algorithm for wear particle classification is proposed in this paper. The algorithm uses the variation of the pixel intensities of a region to choose strong resembling area. Then, the spatial relationships of the membership function are constructed to regulate the pixel membership obtained from the FCM object function. Finally, wear debris are classified based on the fuzzy membership. The example shows that the method is briefly and effectively.

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Modeling constraints to redundancy in bimanual force coordination

Journal of Neurophysiology ◽

10.1152/jn.01086.2010 ◽

2011 ◽

Vol 105 (5) ◽

pp. 2169-2180 ◽

Cited By ~ 14

Author(s):

Xiaogang Hu ◽

Karl M. Newell

Keyword(s):

Muscle Force ◽

Coupling Effect ◽

Isometric Force ◽

Force Production ◽

Force Output ◽

Task Constraints ◽

Task Goal ◽

Force Coordination ◽

Finger Forces ◽

Coordination Patterns

This study investigated the interactive influence of organismic, environmental, and task constraints on the organization of redundant force coordination patterns and the hypothesis that each of the three categories of constraints is weighted based on their relative influence on coordination patterns and the realization of the task goal. In the bimanual isometric force experiment, the task constraint was manipulated via different coefficients imposed on the finger forces such that the weighted sum of the finger forces matched the target force. We examined three models of task constraints based on the criteria of task variance (minimum variance model) and efficiency of muscle force output (coefficient-independent and coefficient-dependent efficiency models). The environmental constraint was quantified by the perceived performance error, and the organismic constraint was quantified by the bilateral coupling effect (i.e., symmetric force production) between hands. The satisficing approach was used in the models to quantify the constraint weightings that reflect the interactive influence of different categories of constraints on force coordination. The findings showed that the coefficient-dependent efficiency model best predicted the redundant force coordination patterns across trials. However, the within-trial variability structure revealed that there was not a consistent coordination strategy in the online control of the individual trial. The experimental findings and model tests show that the force coordination patterns are adapted based on the principle of minimizing muscle force output that is coefficient dependent rather than on the principle of minimizing signal-dependent variance. Overall, the results support the proposition that redundant force coordination patterns are organized by the interactive influence of different categories of constraints.

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Janus-like Fe3O4/PDA vesicles with broadening microwave absorption bandwidth

Journal of Materials Chemistry C ◽

10.1039/c8tc02556h ◽

2018 ◽

Vol 6 (29) ◽

pp. 7790-7796 ◽

Cited By ~ 19

Author(s):

Xiaofeng Shi ◽

Zhengwang Liu ◽

Wenbin You ◽

Xuebing Zhao ◽

Renchao Che

Keyword(s):

Microwave Absorption ◽

Coupling Effect ◽

Magnetic Coupling ◽

Strong Absorption ◽

Frequency Range ◽

Absorption Intensity ◽

Absorption Bandwidth ◽

Measured Frequency ◽

Measured Frequency Range ◽

Pda Vesicles

Fe3O4/PDA vesicle Janus nanospheres were successfully synthesized, and they exhibited an ultra-wide effective band as wide as 11.6 GHz, covering 73% of the whole measured frequency range (2–18 GHz), and a strong absorption intensity as high as −50.0 dB due to the asymmetric polarization and magnetic coupling effect.

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