14,906 results match your criteria Friction Blisters


Dynamics and energy dissipation of a rigid dipole driven by the RF-field in a viscous fluid: Deterministic approach.

Authors:
T V Lyutyy

Eur Phys J E Soft Matter 2018 Dec 10;41(12):142. Epub 2018 Dec 10.

Sumy State University, 2 Rimsky-Korsakov Street, UA-40007, Sumy, Ukraine.

The deterministic rotation of a ferromagnetic nanoparticle in a fluid is considered. The heating arising from viscous friction of a nanoparticle driven by circularly and linearly polarized alternating magnetic fields is investigated. Since the power loss of such fields depends on the character of the induced motion of a nanoparticle, all types of particle trajectories are described in detail. Read More

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December 2018

Tunable Work Function of MgxZn1-xO as a Viable Friction Material for Triboelectric Nanogenerator.

ACS Appl Mater Interfaces 2018 Dec 14. Epub 2018 Dec 14.

Since the invention of triboelectric nanogenerators (TENGs), their output performance has been improved through various approaches such as material surface modification, device structure optimization and so on, but rarely through the development of new friction materials. In this work, magnetron sputtered MgxZn1-xO film is developed as a viable friction material, that rubs against polydimethylsiloxane (PDMS) in TENG. The work function, measured by Kelvin probe microscopy, of the MgxZn1-xO films can be effectively tuned by varying Mg composition, x, and exposed surface facets, which are shown to dominate the charge transfer behavior. Read More

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December 2018
1 Read

DiTe2: Calculating the diffusion tensor for flexible molecules.

J Comput Chem 2018 Dec 14. Epub 2018 Dec 14.

Department of Chemical Sciences, University of Padua, Padova 35131, Italy.

We report on an extended hydrodynamic modeling of the friction tensorial properties of flexible molecules including all types of natural, Z-Matrix like, internal coordinates. We implement the new methodology by extending and updating the software DiTe [Barone et al. J. Read More

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December 2018

Influence of wall heterogeneity on nanoscopically confined polymers.

Phys Chem Chem Phys 2018 Dec 14. Epub 2018 Dec 14.

Dipartimento di Chimica, Materiali e Ingegneria Chimica G. Natta, Politecnico di Milano, via L. Mancinelli 7, 20131 Milano, Italy.

We investigate via molecular dynamics simulations the behaviour of a polymer melt confined between surfaces with increasing spatial correlation (patchiness) of weakly and strongly interacting sites. Beyond a critical patchiness, we find a dramatic dynamic decoupling, characterized by a steep growth of the longest relaxation time and a constant diffusion coefficient. This arises from dynamic heterogeneities induced by the walls in the adjacent polymer layers, leading to the coexistence of fast and slow chain populations. Read More

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December 2018

Buoyancy-Driven Flow through a Bed of Solid Particles Produces a New Form of Rayleigh-Taylor Turbulence.

Phys Rev Lett 2018 Nov;121(22):224501

Department of Civil, Chemical, and Environmental Engineering, University of Genova and INFN, via Montallegro 1, 16145 Genova, Italy.

Rayleigh-Taylor (RT) fluid turbulence through a bed of rigid, finite-size spheres is investigated by means of high-resolution direct numerical simulations, fully coupling the fluid and the solid phase via a state-of-the-art immersed boundary method. The porous character of the medium reveals a totally different physics for the mixing process when compared to the well-known phenomenology of classical RT mixing. For sufficiently small porosity, the growth rate of the mixing layer is linear in time (instead of quadratical) and the velocity fluctuations tend to saturate to a constant value (instead of linearly growing). Read More

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November 2018

An appraisal of properties of dental amalgam using commercially available and ayurvedically recycled mercury: Recycle and reuse.

J Conserv Dent 2018 Nov-Dec;21(6):651-656

Department of Mechanical Engineering, IIT, BHU, Varanasi, Uttar Pradesh, India.

Introduction: With the introduction of tooth-colored restoration material, the usage of amalgam has reduced over years. However, results regarding toxicity and health concerns are conflicting. Based on the concept of recycle and reuse, we previously used an ayurvedic method for purification of excess mercury obtained from dental operatory. Read More

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December 2018

Effects of Laser Texture Oxidation and High-Temperature Annealing of TiV Alloy Thin Films on Mechanical and Antibacterial Properties and Cytotoxicity.

Materials (Basel) 2018 Dec 8;11(12). Epub 2018 Dec 8.

School of Dentistry, China Medical University, Taichung 404, Taiwan.

Titanium dioxide and vanadium oxides have been applied extensively in industrial and medical fields. The objective of this study was to develop various composite structures of titanium and vanadium oxide (Ti-V-O) coatings on pure titanium through high-temperature annealing and laser texturing oxidation, separately; additionally, surface morphologies, tribological and hydrophilic properties, and antibacterial and biocompatibility abilities of these Ti-V-O coatings were evaluated. TiV alloy thin films were deposited on pure titanium and then annealed to form Ti-V-O coatings through thermal oxidation and laser texturing oxidation. Read More

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December 2018

Fundamentals of Force-Controlled Friction Riveting: Part II-Joint Global Mechanical Performance and Energy Efficiency.

Materials (Basel) 2018 Dec 7;11(12). Epub 2018 Dec 7.

Institute of Materials Science, Joining and Forming, BMVIT Endowed Professorship for Aviation, Graz University of Technology, 8010 Graz, Austria.

The present work investigates the correlation between energy efficiency and global mechanical performance of hybrid aluminum alloy AA2024 (polyetherimide joints), produced by force-controlled friction riveting. The combinations of parameters followed a central composite design of experiments. Joint formation was correlated with mechanical performance via a volumetric ratio (0. Read More

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December 2018
1 Read

Chest injuries of elderly postmortem human surrogates (PMHSs) under seat belt and airbag loading in frontal sled impacts: Comparison to matching THOR tests.

Traffic Inj Prev 2018 Dec 13:1-9. Epub 2018 Dec 13.

d Biomechanics and Accident Analysis , Ludwig Maximilians University , Munich , Germany.

Objective: The goal of the study was to develop experimental chest loading conditions that would cause up to Abbreviated Injury Scale (AIS) 2 chest injuries in elderly occupants in moderate-speed frontal crashes. The new set of experimental data was also intended to be used in the benchmark of existing thoracic injury criteria in lower-speed collision conditions.

Methods: Six male elderly (age >63) postmortem human subjects (PMHS) were exposed to a 35 km/h (nominal) frontal sled impact. Read More

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December 2018

Homogenous-heterogeneous reactions in MHD flow of Powell-Eyring fluid over a stretching sheet with Newtonian heating.

Neural Comput Appl 2018 24;30(11):3581-3588. Epub 2017 Mar 24.

1Department of Mathematics, Quaid-i-Azam University, Islamabad, 44000 Pakistan.

This article addresses the effects of homogenous-heterogeneous reactions on electrically conducting boundary layer fluid flow and heat transfer characteristics over a stretching sheet with Newtonian heating are examined. Using similarity transformations, the governing equations are transformed into nonlinear ordinary differential equations. The constricted ordinary differential equations are solved computationally by shooting technique. Read More

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An earthworm-inspired friction-controlled soft robot capable of bidirectional locomotion.

Bioinspir Biomim 2018 Oct 11. Epub 2018 Oct 11.

University of Southern California, Los Angeles, California, 90089-0001, UNITED STATES.

We present the design, fabrication, modeling and feedback control of an earthworm-inspired soft robot capable of bidirectional locomotion on flat and angled platforms, by actively controlling the robot's coefficient of friction between the contacting surfaces. Earthworms are characterized by their segmented body structures, known as metameres. To locomote, their longitudinal and circular muscles contract and relax accord- ingly, generating a peristaltic wave that propagates backwards with respect to the worms' traveling direction. Read More

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October 2018

Mechanisms of Friction Reduction of Nanoscale Sliding Contacts Achieved Through Ultrasonic Excitation.

Nanotechnology 2018 Nov 26. Epub 2018 Nov 26.

Mechanical and Manufacturing Engineering, University of Calgary, 2500 University Drive NW, MEB 419, Calgary, Alberta, T2N 1N4, CANADA.

Friction reduction is an important issue for proper functioning of nano-/micro-electromechanical systems (N-/MEMS) due to their large surface to volume ratios and the inability of traditional liquid lubricants to effectively lubricate sliding contacts. One efficient technique to achieve substantially lowered friction at nanoscale, as well as superlubricity in some instances, was investigated with the coupling of ultrasonic actuation of the sliding contact in an atomic force microscope (AFM). Despite the successful application of ultrasonic AFM methods in achieving mechanical property measurements and nanoscale subsurface imaging of soft and hard materials, the mechanism of friction reduction in the microscopic contact and the influence of the ultrasonic parameters on friction reduction are still elusive. Read More

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November 2018

Experimental evaluation of pressure drop for flows of air and heliox through upper and central conducting airway replicas of 4- to 8-year-old children.

J Biomech 2018 Oct 27. Epub 2018 Oct 27.

Department of Mechanical Engineering, University of Alberta, Canada. Electronic address:

Airway resistance describes the ratio between pressure drop and flow rate through the conducting respiratory airways. Analytical models of airway resistance for tracheobronchial airways have previously been developed and assessed without upper airways positioned upstream of the trachea. This work investigated pressure drop as a function of flow rate and gas properties for upper and central airway replicas of 10 child subjects, ages 4-8. Read More

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October 2018

A semi-empirical model of the energy balance closure in the surface layer.

PLoS One 2018 12;13(12):e0209022. Epub 2018 Dec 12.

Karlsruhe Institute of Technology, Institute of Meteorology and Climate Research - Atmospheric Environmental Research, Garmisch-Partenkirchen, Germany.

It has been hypothesized that the energy balance closure problem of single-tower eddy-covariance measurements is linked to large-scale turbulent transport. In order to shed light on this problem, we investigate the functional dependence of the normalized residual for the potential temperature and humidity conservation equations, i.e. Read More

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December 2018

Live nanoscopic to mesoscopic topography reconstruction with an optical microscope for chemical and biological samples.

PLoS One 2018 12;13(12):e0207881. Epub 2018 Dec 12.

LAI, Aix Marseille Univ, CNRS, INSERM, Marseille, France.

Macroscopic properties of physical and biological processes like friction, wetting, and adhesion or cell migration are controlled by interfacial properties at the nanoscopic scale. In an attempt to bridge simultaneously investigations at different scales, we demonstrate here how optical microscopy in Wet-Surface Ellipsometric Enhanced Contrast (Wet-SEEC) mode offers imaging and measurement of thin films at solid/liquid interfaces in the range 1-500 nm with lateral optical resolution. A live, label-free and noninvasive methodology integrated with microfluidic devices allowed here characterization of polymers and proteins patterns together with corresponding phenotypes of living cells. Read More

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December 2018

Use of Assistive Devices to Lift, Transfer, and Reposition Hospital Patients.

Nurs Res 2019 Jan/Feb;68(1):3-12

Ashley Schoenfisch, PhD, MSPH, is Assistant Professor, Duke University School of Nursing, and Division of Occupational and Environmental Medicine, Department of Community and Family Medicine, Duke University School of Medicine, Durham, North Carolina. Kristen L. Kucera, PhD, MSPH, ATC, LAT, is Assistant Professor, Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, and Director, National Center for Catastrophic Sport Injury Research, University of North Carolina at Chapel Hill. Hester J. Lipscomb, PhD, is Professor Emeritus, Division of Occupational and Environmental Medicine, Department of Community and Family Medicine, Duke University School of Medicine, Durham, North Carolina. Jennifer McIlvaine, PT, MSPT, CSPHA, is Physical Therapist, Safe Patient Handling Specialist, Duke Occupational and Environmental Safety Office, Durham, North Carolina. Lori Becherer, BS, is Staff Specialist, Duke Occupational and Environmental Safety Office, Durham, North Carolina, and Injury Prevention Research Center, University of North Carolina at Chapel Hill. Tamara James, MA, CPE, CSPHP, is Director, Ergonomics, Duke Occupational and Environmental Safety Office, and Assistant Professor, Division of Occupational and Environmental Medicine, Department of Community and Family Medicine, Duke University School of Medicine, Durham, North Carolina. Susan Avent, MSN, MBA, MHA, RN, NEA-BC, is Associate Chief Nursing Officer, Quality, Duke University Health System, Durham, North Carolina.

Background: Devices to lift, transfer, and reposition patients are recommended for healthcare workers' and patients' safety, but their intended use has yet to be fully realized.

Objective: The aim of this study was to describe hospital nursing staff use of lift/transfer devices and the presence of factors at the time of lifts/transfers with potential to influence whether devices are used.

Methods: Participants were 108 US nursing staff in a university-based medical center and two community hospitals. Read More

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December 2018
2 Reads

An experimental investigation into the surface and hydrodynamic characteristics of marine coatings with mimicked hull roughness ranges.

Biofouling 2018 Dec 11:1-19. Epub 2018 Dec 11.

b Department of Naval Architecture, Ocean and Marine Engineering , University of Strathclyde , Glasgow , UK.

There are limited scientific data on contributors to the added drag of in-service ships, represented by modern-day coating roughness and biofouling, either separately or combined. This study aimed to gain an insight into roughness and hydrodynamic performance of typical coatings under in-service conditions of roughened ships' hull surfaces. Comprehensive and systematic experimental data on the boundary layer and drag characteristics of antifouling coating systems with different finishes are presented. Read More

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December 2018
1 Read

A case of fractured guide wire perforating the coronary artery and ascending aorta during percutaneous coronary intervention.

J Cardiol Cases 2013 May 13;7(5):e137-e141. Epub 2013 Feb 13.

Division of Cardiovascular Surgery, Nagoya City East Medical Center, Nagoya, Japan.

We experienced a rare and serious case of fractured hydrophilic guide wire necessitating surgical intervention during percutaneous coronary intervention (PCI) for a tortuous and calcified stenosis in the proximal right coronary artery. An 85-year-old female presented to our hospital and was diagnosed as having unstable angina. A 0. Read More

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Deformation mechanisms of polytetrafluoroethylene at the nano- and microscales.

Phys Chem Chem Phys 2018 Dec 11. Epub 2018 Dec 11.

Multiscale Materials Modeling Lab, Department of Mechanical Engineering, University of Arkansas, Fayetteville, AR, USA. and Institute for Nanoscience and Engineering, University of Arkansas, 731 W. Dickson Street, Fayetteville, AR-72701, USA.

Polytetrafluoroethylene (PTFE) has not only a low coefficient of friction but also a high wear rate. Numerous studies investigating the possibility of reducing wear and the mechanisms of deformation have been conducted using experimental and computational studies. In this paper the deformation and mechanical failure of single chains and bulk PTFE are investigated using molecular dynamics (MD). Read More

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December 2018
1 Read

Recent updates for biomaterials used in total hip arthroplasty.

Biomater Res 2018 5;22:33. Epub 2018 Dec 5.

Center for Joint Disease, Chonnam National University Hwasun Hospital, 160, Ilsim-Ri, Hwasun-Eup, Hwasun-Gun, Jeonnam 519-809 South Korea.

Background: Total hip arthroplasty (THA) is probably one of the most successful surgical interventions performed in medicine. Through the revolution of hip arthroplasty by principles of low friction arthroplasty was introduced by Sir John Charnley in 1960s. Thereafter, new bearing materials, fixation methods, and new designs has been improved. Read More

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December 2018

Measuring the Effects of Employment Protection Policies: Theory and Evidence from the Americans with Disabilities Act.

Labour Econ 2018 Oct 13;54:116-134. Epub 2018 Aug 13.

Rhee: Korea Development Institute, 263 Namsejong-ro, Sejong City 30149, Republic of Korea.

Title I of the Americans with Disabilities Act (ADA) is an employment protection policy for disabled workers. By exploiting cross-state variation in pre-ADA legislation, we measure the effects of the law on transition rates of disabled workers. We find a decline in employment-to-non-employment transitions after the ADA, with an insignificant change in flow into employment. Read More

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October 2018

Tribological and antioxidation properties study of two N-containing borate ester derivatives as additive in rapeseed oil.

PLoS One 2018 10;13(12):e0207267. Epub 2018 Dec 10.

School of Materials Science and Engineering, East China Jiaotong University, Nanchang, China.

Two kinds of phenol- and N- containing borate ester, BTEB and BMEB have good hydrolysis stability due to the B-N coordination bond. The PB value improved by 60.7% and 67. Read More

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December 2018

3D tribo-nanoprinting using triboreactive materials.

Nanotechnology 2018 Dec 7. Epub 2018 Dec 7.

University of Leeds, Leeds, UNITED KINGDOM OF GREAT BRITAIN AND NORTHERN IRELAND.

Tribology: the science of friction, wear and lubrication has never been associated in a positive way with the ability to manufacture at the nanoscale. Triboreactivity, when the contact between two surfaces promotes a chemical reaction, has been harnessed in this study to create highly tenacious nano-features. The reported 3D tribo-nanoprinting methodology has been demonstrated for organic and inorganic fluids on steel and silicon substrates and is adaptable through the interface tribology. Read More

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December 2018
1 Read

Traction reinforcement in prehensile feet of harvestmen (Arachnida, Opiliones).

J Exp Biol 2018 Dec 10. Epub 2018 Dec 10.

Functional Morphology and Biomechanics, University of Kiel, Am Botanischen Garten 1-9, 24098 Kiel, Germany.

Prehensile and gripping organs are recurring structures in different organisms that enhance friction by the reinforcement and redirection of normal forces. The relationship between organ structure and biomechanical performance is poorly understood, despite a broad relevance for microhabitat choice, movement ecology and biomimetics. Here, we present the first study of the biomechanics of prehensile feet in long-legged harvestmen. Read More

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December 2018

Probabilistic, safety-explicit design of horizontal curves on two-lane rural highways based on reliability analysis of naturalistic driving data.

Accid Anal Prev 2018 Dec 4;123:200-210. Epub 2018 Dec 4.

Department of Civil and Environmental Engineering, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, K1S5B6, Canada. Electronic address:

The high collision rates on horizontal curves compared to other roadway elements make them one of the most critical elements in a transportation network. In this regard, it is important to develop models to predict the safety performance of the horizontal curves. A considerable number of studies have been conducted to develop safety performance functions based on several concepts such as geometric characteristics, design consistency, reliability analysis, and comfort threshold. Read More

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December 2018

On the breakdown of the Ehrenfest method for molecular dynamics on surfaces.

J Chem Phys 2018 Dec;149(21):214101

Chemical Physics Theory Group, Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada and Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada.

Due to a continuum of electronic states present in periodic systems, the description of molecular dynamics on surfaces poses a serious computational challenge. One of the most used families of approaches in these settings are friction theories, which up to a random fluctuating force term are based on the Ehrenfest approach. Yet, a mean-field treatment of electronic degrees of freedom in the Ehrenfest method makes this approach inaccurate in some cases. Read More

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December 2018

Stochastic unfolding of nanoconfined DNA: Experiments, model and Bayesian analysis.

J Chem Phys 2018 Dec;149(21):215101

Department of Astronomy and Theoretical Physics, Lund University, Lund, Sweden.

Nanochannels provide a means for detailed experiments on the effect of confinement on biomacromolecules, such as DNA. Here we introduce a model for the complete unfolding of DNA from the circular to linear configuration. Two main ingredients are the entropic unfolding force and the friction coefficient for the unfolding process, and we describe the associated dynamics by a non-linear Langevin equation. Read More

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December 2018
1 Read

Oxidative Cyclization Protocol for the Preparation of Energetic 3-Amino-5- R-1,2,4-oxadiazoles.

Org Lett 2018 Dec 10. Epub 2018 Dec 10.

Department of Chemistry , University of Idaho , Moscow , Idaho 83844-2343 , United States.

An efficient method has been developed for the synthesis of energetic 3-amino-5- R-1,2,4-oxadiazoles via iodobenzene diacetate (IBD)-mediated oxidative cyclization in high yields at ambient temperature. Compound 1c has a graphite-like structure, which has seldom been reported in bicyclic compounds. The reaction of 3-amino-5- R-1,2,4-oxadiazole derivatives with hydrazine monohydrate in THF gives products that are a function of the substituent. Read More

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December 2018

Are Buckminsterfullerenes "Molecular Ball Bearings"?

J Phys Chem B 2018 Dec 10. Epub 2018 Dec 10.

Buckminsterfullerenes (C60) are near-spherical molecules which freely rotate at room temperature in the solid state and when dissolved in solution. An intriguing question arises as to whether C60 molecules can act as 'molecular ball bearings', i.e. Read More

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December 2018

Triple Function Lubricant Additives Based on Organic-inorganic Hybrid Star Polymers: Friction Reduction, Wear Protection, and Viscosity Modification.

ACS Appl Mater Interfaces 2018 Dec 10. Epub 2018 Dec 10.

Polymer-based lubricant additives for friction reduction, wear protection or viscosity improvement have been widely studied. However, single additives achieving all three functions are rare. To address this need, we have explored the combination of polymer topology with organic-inorganic hybrid chemistry to simultaneously vary the temperature- and shear-dependent properties of polymer additives in solution and at solid surfaces. Read More

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December 2018

Occurrence and human exposure assessment of short- and medium-chain chlorinated paraffins in dusts from plastic sports courts and synthetic turf in Beijing, China.

Environ Sci Technol 2018 Dec 6. Epub 2018 Dec 6.

This study presents the first investigation of concentrations and congener group patterns of short- and medium-chain chlorinated paraffins (SCCPs and MCCPs) in 159 dust samples from plastic sports courts and synthetic turf in Beijing, China. The geometric mean concentration of SCCPs and MCCPs in dusts from plastic tracks (5429 and 15157 μg g-1) and basketball courts (5139 and 11878 μg g-1) were significantly higher than those from plastic tennis courts, badminton courts, and synthetic turf, meanwhile they were 1-3 orders of magnitude higher than those in dusts from other indoor environments. The friction between sneaker soles and plastic track materials may lead to the wear and decomposition of rubber, which may be an important source of chlorinated paraffins (CPs) in the dust from plastic tracks. Read More

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December 2018
4 Reads
5.330 Impact Factor

The Influence of Suspension Containing Nanodiamonds on the Morphology of the Tooth Tissue Surface in Atomic Force Microscope Observations.

Biomed Res Int 2018 5;2018:9856851. Epub 2018 Nov 5.

Department of Material Science, Technical University of Liberec, Studentská 1402/2, 46117 Liberec 1, Czech Republic.

Reduced friction and wear of materials after the use of the carbon nanomaterials including nanodiamonds (NDs) have been confirmed by several studies in material engineering. Mechanical cleaning of the tooth surface by brush bristles should leave as little tissue roughened as possible. Higher surface roughness increases the tissue's wear and encourages the redeposition of the bacteria and the colouring agents present in the diet. Read More

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November 2018
2 Reads

Ultralow Interlayer Friction of Layered Electride Ca₂N: A Potential Two-Dimensional Solid Lubricant Material.

Materials (Basel) 2018 Dec 4;11(12). Epub 2018 Dec 4.

Computational and Design Center for Low-dimensional Quantum Material, and College of Science, Zhongyuan University of Technology, Zhengzhou 450007, China.

Dispersion-corrected density functional theory (DFT) calculations reveal that the layered electride of dicalcium nitride (Ca₂N) exhibits stronger interlayer binding interactions but lower interlayer friction behavior than that of traditional layered lubricants weakly bonded by van der Waals (vdW) interactions, such as graphite, -BN, and MoS₂. These results are attributed to the two-dimensional (2D) homogeneous conduction electrons distribution in the middle of the interlayer space of Ca₂N, which yields a smooth sliding barrier and hence ultralow friction behavior. The interesting results obtained in this study have not only broadened the scope of 2D solid lubricants but also enriched the physical understanding of ultralow friction mechanism for 2D systems. Read More

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December 2018

Experimental Evaluation of Interfacial Surface Cracks in Friction Welded Dissimilar Metals through Image Segmentation Technique (IST).

Materials (Basel) 2018 Dec 4;11(12). Epub 2018 Dec 4.

Department of Mechanical Engineering, College of Engineering, King Khalid University, PO Box 9004, Abha 61413, Asir, Kingdom Saudi Arabia.

Surface cracks on the friction welded interface of dissimilar metals are one of the earliest indications of degradation of the joint, which is a critical aspect for the welding strength. By manual inspection of the friction welded joint, observations of irregularities, porosity voids, crack lengths, cracked surfaces, and depth penetrations of two dissimilar metals can be made. Manual inspection purely depends on a quality expert's experience of quantitative analysis and knowledge. Read More

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December 2018
1 Read

Nano- and microscale mechanical properties of erythrocytes in hereditary spherocytosis.

J Biomech 2018 Nov 16. Epub 2018 Nov 16.

Research Institute for Applied Problems of Mathematics and Informatics, Belarusian State University, Nezavisimosti Ave., 4, 220030 Minsk, Belarus.

Hereditary spherocytosis (HS), an erythrocyte membranopathy, is a heterogeneous disease, even at the level of the erythrocyte population. The paper aims at studying the mechanical properties (the Young's modulus, median and RMS roughness of friction force maps; fractal dimension, lacunarity and spatial distribution parameters of lateral force maps) of the cell surface layer of the erythrocytes of two different morphologies (discocytes and spherocytes) in HS using atomic force microscopy. The results of spatial-spectral and fractal analysis showed that the mechanical property maps of the HS spherocyte surface were more structurally homogeneous compared to the maps of HS discocytes. Read More

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November 2018
1 Read

Relation between structural, mechanical and sensory properties of gluten-free bread as affected by modified dietary fibers.

Food Chem 2019 Mar 2;277:664-673. Epub 2018 Nov 2.

Department of Mechanical Engineering, Munich School of Bioengineering, Technical University of Munich, Boltzmannstraße 11, 85748 Garching, Germany.

Gluten-free bread was fortified with modified dietary fibers (wheat bran, resistant starch and inulin) and their effects on water mobility, friction coefficient, thermal behavior, crystalline pattern and textural properties were evaluated. Moreover, time-intensity evaluation was used to study temporal dynamics of sensory attributes of fortified-breads. Dietary fibers increased gelatinization temperature while decreasing gelatinization enthalpy, more notably when inulin was used. Read More

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Graphene used as a lateral force microscopy calibration material in the low-load non-linear regime.

Rev Sci Instrum 2018 Nov;89(11):113902

Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506, USA.

A lateral force microscopy (LFM) calibration technique utilizing a random low-profile surface is proposed that is successfully employed in the low-load non-linear frictional regime using a single layer of graphene on a supporting oxide substrate. This calibration at low loads and on low friction surfaces like graphene has the benefit of helping to limit the wear of the LFM tip during the calibration procedure. Moreover, the low-profiles of the calibration surface characteristic of these layered 2D materials, on standard polished oxide substrates, result in a nearly constant frictional, adhesive, and elastic response as the tip slides over the surface, making the determination of the calibration coefficient robust. Read More

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November 2018

Note: Rotor design optimization for vacuum chamber-free ultracentrifuge.

Rev Sci Instrum 2018 Nov;89(11):116107

Department of Mechanical Engineering, KAIST, Daejeon 305-701, Korea.

This paper proposes a fixed-angle rotor design for a vacuum chamber-free ultracentrifuge using a rigid shaft and magnetic bearings. The rotor is designed for a stable operation in the ultracentrifugation region with air friction. And the optimal design parameters and optimized connection method of the rotor and rigid shaft are proposed. Read More

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November 2018
1 Read

Tribological Behavior of Copper⁻Graphite Composites Reinforced with Cu-Coated or Uncoated SiO₂ Particles.

Materials (Basel) 2018 Nov 29;11(12). Epub 2018 Nov 29.

Key Laboratory of Advanced Structural Materials, Ministry of Education, Changchun University of Technology, Changchun 130012, China.

Copper⁻graphite composites reinforced with SiO₂ particles were fabricated by powder metallurgy technique. Electroless copper plating was introduced to improve the interfacial bonding between SiO₂ particles and copper matrix. The microstructure, density, and hardness of the composites were characterized. Read More

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November 2018

Paper-based Versatile SERS Chip with Smartphone-based Raman Analyzer for Point of Care Application.

Anal Chem 2018 Dec 5. Epub 2018 Dec 5.

With the advanced development of the miniaturized Raman spectroscopy, surface enhanced Raman spectroscopy (SERS) has extended its applications into the field of Point of Care Testing (POCT) and demonstrated its great significance in virtue non-invasive property and capability of fingerprint identification. In the SERS-based analysis and/or sensing system, the preparation of low cost, high-performance SERS substrate is critically important. In this manuscript, vacuum filtration is utilized to fabricate the silver nanoparticles (AgNPs) embedded nylon filter membrane (ANFM) as flexible paper-based SERS chips. Read More

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December 2018
2 Reads

Detection of Friction Stir Welding Defects of AA1060 Aluminum Alloy Using Specific Damping Capacity.

Materials (Basel) 2018 Nov 30;11(12). Epub 2018 Nov 30.

Mechanical Engineering Departments, Faculty of Engineering, King Abdulaziz University, Jeddah 21589, Saudi Arabia.

The demand for nondestructive testing has increased, especially in welding testing. In the current study, AA1060 aluminum plates were jointed using the friction stir welding (FSW) process. The fabricated joints were subjected to free vibration impact testing in order to investigate the dynamic properties of the welded joint. Read More

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November 2018

Tribological Behavior of Lamellar Molybdenum Trioxide as a Lubricant Additive.

Materials (Basel) 2018 Nov 30;11(12). Epub 2018 Nov 30.

School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China.

In this study, the tribological behavior of lamellar MoO₃ as a lubricant additive was investigated under different concentrations, particle sizes, normal loads, velocity, and temperature. The friction and wear tests were performed using a tribometer and with a reciprocating motion. The results indicate that the friction-reducing ability and antiwear property of the base oil can be improved effectively with the addition of lamellar MoO₃. Read More

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November 2018

Quantifying machining outputs of pristine human teeth relevant to dental preparation procedures.

J Mech Behav Biomed Mater 2018 Nov 16;91:1-9. Epub 2018 Nov 16.

Department of Mechanical, Aerospace, and Nuclear Engineering Rensselaer Polytechnic Institute, Troy, NY 12180, USA. Electronic address:

Minimally-assisted tooth repair (MaTR) systems are envisioned to be capable of substituting for the skill of a dentist. If successfully developed, MaTR systems could enable lower-skilled dental technicians to provide dental care at a fraction of the overall medical cost. This paper explores a key initial step towards the development of such systems by quantifying the machining responses of pristine human teeth relevant to dental preparation procedures. Read More

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November 2018
1 Read

Dynamic Stability Assessment of the Temporomandibular Joint as a Sequela of Open Reduction and Internal Fixation of Unilateral Condylar Fracture.

J Oral Maxillofac Surg 2018 Dec 15;76(12):2598-2609. Epub 2018 Jun 15.

Professor, Department of Oral and Maxillofacial Surgery, Sri Sai College of Dental Surgery, Vikarabad, India.

Purpose: Dynamic stability of the temporomandibular joint (TMJ) is the characteristic of the joint to achieve normal function by harmonious, balanced, synchronized interactions of the various functional subunits of the stomatognathic system. The aim of this study was to evaluate changes in the mechanics and dynamics of the TMJ during recovery from surgical treatment of an isolated condylar fracture.

Patients And Methods: This is a prospective cohort study involving 30 patients who underwent open reduction and internal fixation for an isolated unilateral condylar fracture and were clinically asymptomatic at 6 months after surgery. Read More

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December 2018
1 Read

Imaging Features of Symptomatic Hypertrophic Tuberculum Peroneum.

J Belg Soc Radiol 2017 Dec 16;101(Suppl 2). Epub 2017 Dec 16.

AZ Sint-Maarten and University (Hospital) Antwerp/Ghent, BE.

Objective: The aim of this article is to review the clinical and imaging features of symptomatic hypertrophic (TP) in a cohort of symptomatic patients.

Materials And Methods: Twenty-three patients with chronic lateral ankle pain were retrospectively included in our study group. Patients underwent ultrasound (US), (cone beam) computed tomography (CB)CT or magnetic resonance (MR) examination or a combination of these examinations with a standardized protocol. Read More

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December 2017
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Prevalence and risk factors of pressure ulcer in hospitalized adult patients; a single center study from Ethiopia.

BMC Res Notes 2018 Nov 29;11(1):847. Epub 2018 Nov 29.

School of Nursing, College of Medicine & Health Sciences, University of Gondar, Gondar, Ethiopia.

Objective: The main objective of this study was to assess the prevalence of pressure ulcer and its risk factors among adult hospitalized patients at Dessie Referral Hospital, Northeast Ethiopia, 2016 G.

C Result: A cross-sectional institutional based study with a single population proportion formula was used to determine the sample size. The total sample size of 355 patients was distributed proportionally to the respected wards. Read More

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November 2018
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A swing arm device for the acoustic measurement of food texture.

J Texture Stud 2018 Nov 29. Epub 2018 Nov 29.

Department of Physics, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Praha, Czech Republic.

We developed a swing arm device for acoustic measurement of food texture, which resolved difficulties of food texture evaluation. The device has a structure of balance-style and a probe in the device is moved downward along with motion of swing arm according to the balance of weights at both ends of the swing arm. The probe was inserted into a food sample. Read More

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November 2018

Characteristics of persistent diaper dermatitis in children with food allergy.

Pediatr Dermatol 2018 Nov 28. Epub 2018 Nov 28.

Department of Pediatrics, Medical Faculty, Inonu University, Malatya, Turkey.

Background/objectives: Diaper dermatitis is often caused by irritant contact occurring beneath the diaper of an infant, and it is aggravated by factors such as dampness, friction, urea, and feces. Food-allergic patients are known to exhibit various skin lesions ranging from urticaria to eczema. This study aims to determine the relationship between persistent diaper dermatitis and food allergy. Read More

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November 2018
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