scholarly journals Hybrid Graphene-Based Photonic-Plasmonic Biochemical Sensor with a Photonic and Acoustic Cavity Structure

Crystals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1175
Author(s):  
Chan-Shan Yang ◽  
Yi-Sheng Cheng ◽  
Young-Chou Hsu ◽  
Yi-Cheng Chung ◽  
Jing-Ting Hung ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Resonant Cavity ◽  
Viscoelastic Model ◽  
Small Sample ◽  
Molecular Vibration ◽  
Molecular Fingerprints ◽  
Biochemical Sensor ◽  
Resonance Shift ◽  
Cavity Structure ◽  
Band Gap Structure

In this study, we propose a biochemical sensor that features a photonic cavity integrated with graphene. The tunable hybrid plasmonic-photonic sensor can detect the molecular fingerprints of biochemicals with a small sample volume. The stacking sequence of the device is “ITO grating/graphene/TiO2/Au/Si substrate”, which composes a photonic band gap structure. A defect is created within the ITO gratings to form a resonant cavity. The plasmonic-photonic energy can be confined in the cavity to enhance the interaction between light and the analyte deposited in the cavity. The finite element simulation results indicated that the current sensor exhibits very high values in resonance shift and sensitivity. Moreover, the resonance spectrum with a broad resonance linewidth can identify the molecular vibration bands, which was exemplified by the fingerprint detections of protein and the chemical compound CBP. The sensor possesses an electrical tunability by including a graphene layer, which allowed us to tune the effective refractive index of the cavity to increase the sensor’s sensing performance. In addition, our device admits a phononic bandgap as well, which was exploited to sense the mechanical properties of two particular dried proteins based on the simplified elastic material model instead of using the more realistic viscoelastic model. The dual examinations of the optical and mechanical properties of analytes from a phoxonic sensor can improve the selectivity in analyte detections.

scholarly journals Demonstration of a Label-Free and Low-Cost Optical Cavity-Based Biosensor Using Streptavidin and C-Reactive Protein

Biosensors ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 4
Author(s):  
Donggee Rho ◽  
Seunghyun Kim
Keyword(s):  
Limit Of Detection ◽  
Point Of Care ◽  
Low Cost ◽  
Optical Cavity ◽  
Sample Volume ◽  
Small Sample ◽  
Label Free ◽  
C Reactive Protein ◽  
Reactive Protein ◽  
Cavity Structure

An optical cavity-based biosensor (OCB) has been developed for point-of-care (POC) applications. This label-free biosensor employs low-cost components and simple fabrication processes to lower the overall cost while achieving high sensitivity using a differential detection method. To experimentally demonstrate its limit of detection (LOD), we conducted biosensing experiments with streptavidin and C-reactive protein (CRP). The optical cavity structure was optimized further for better sensitivity and easier fluid control. We utilized the polymer swelling property to fine-tune the optical cavity width, which significantly improved the success rate to produce measurable samples. Four different concentrations of streptavidin were tested in triplicate, and the LOD of the OCB was determined to be 1.35 nM. The OCB also successfully detected three different concentrations of human CRP using biotinylated CRP antibody. The LOD for CRP detection was 377 pM. All measurements were done using a small sample volume of 15 µL within 30 min. By reducing the sensing area, improving the functionalization and passivation processes, and increasing the sample volume, the LOD of the OCB are estimated to be reduced further to the femto-molar range. Overall, the demonstrated capability of the OCB in the present work shows great potential to be used as a promising POC biosensor.

scholarly journals A fracture mechanics model for a crack problem of functionally graded materials with stochastic mechanical properties

2012 ◽  
Vol 468 (2146) ◽  
pp. 2939-2961 ◽  
Author(s):  
Licheng Guo ◽  
Zhihai Wang ◽  
Naotake Noda
Keyword(s):  
Mechanical Properties ◽  
Fracture Mechanics ◽  
Functionally Graded Materials ◽  
Small Sample ◽  
Functionally Graded ◽  
Phase Volume ◽  
Graded Materials ◽  
Volume Fractions ◽  
Mechanics Model ◽  
Crack Problems

This study aimed to develop a method to build a ‘bridge’ between the macro fracture mechanics model and stochastic micromechanics-based properties so that the macro fracture mechanics model can be expanded to the fracture mechanics problem of functionally graded materials (FGMs) with stochastic mechanical properties. An analytical fracture mechanics model is developed to predict the stress intensity factors (SIFs) in FGMs with stochastic uncertainties in phase volume fractions. Considering the stochastic description of the phase volume fractions, a micromechanics-based method is developed to derive the explicit probabilistic characteristics of the effective properties of the FGMs so that the stochastic mechanical properties can be combined with the macro fracture mechanics model. A thought for choosing the samples efficiently is proposed so that the stable probabilistic characteristic of SIFs can be obtained with a very small sample size. The probability density function of SIFs can be determined by developing a histogram from the generated samples. The present method may provide a thought to establish an analytical model for the crack problems of FGMs with stochastic properties.

Effects of elastase on the mechanical and failure properties of engineered elastin-rich matrices

2005 ◽  
Vol 98 (4) ◽  
pp. 1434-1441 ◽  
Author(s):  
Lauren D. Black ◽  
Kelly K. Brewer ◽  
Shirley M. Morris ◽  
Barbara M. Schreiber ◽  
Paul Toselli ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Viscoelastic Model ◽  
Enzymatic Digestion ◽  
Dynamic Mechanical Properties ◽  
Force Transducer ◽  
Neonatal Rat ◽  
Fiber Failure ◽  
Elastin Fiber ◽  
Function Relationship ◽  
Relationship Of

Pulmonary emphysema and vessel wall aneurysms are diseases characterized by elastolytic damage to elastin fibers that leads to mechanical failure. To model this, neonatal rat aortic smooth muscle cells were cultured, accumulating an extracellular matrix rich in elastin, and mechanical measurements were made before and during enzymatic digestion of elastin. Specifically, the cells in the cultures were killed with sodium azide, the cultures were lifted from the flask, cut into small strips, and fixed to a computer-controlled lever arm and a force transducer. The strips were subjected to a broadband displacement signal to study the dynamic mechanical properties of the samples. Also, quasi-static stress-strain curves were measured. The dynamic data were fit to a linear viscoelastic model to estimate the tissues' loss (G) and storage (H) modulus coefficients, which were evaluated before and during 30 min of elastase treatment, at which point a failure test was performed. G and H decreased significantly to 30% of their baseline values after 30 min. The failure stress of control samples was ∼15 times higher than that of the digested samples. Understanding the structure-function relationship of elastin networks and the effects of elastolytic injury on their mechanical properties can lead to the elucidation of the mechanism of elastin fiber failure and evaluation of possible treatments to enhance repair in diseases involving elastolytic injury.

scholarly journals Finite Element Analysis of the Nanomechanics of Hard Coatings on a Soft Polymer Substrate by a Spherical Indenter

2020 ◽  
Vol 2020 ◽  
pp. 1-11 ◽  
Author(s):  
Chunlai Tian ◽  
Pengfei Duan
Keyword(s):  
Mechanical Properties ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Viscoelastic Model ◽  
Coating System ◽  
Element Analysis ◽  
Soft Polymer ◽  
Indentation Response

Composite has been widely used in various fields due to its advanced performance. To reveal the relation between the mechanical properties of the composite and that of each individual component, finite element analysis (FEA) has usually been adopted. In this study, in order to predict the mechanical properties of hard coating on a soft polymer, the response of this coating system during nanoindentation was modelled. Various models, such as a viscoelastic model and fitting model, were adopted to analyse the indentation response of this coating system. By varying the substrate properties (i.e., Young’s modulus, viscoelasticity, and Poisson’s ratio), Young’s modulus, energy loss, and the viscoelastic model of the coating system were analysed, and how the mechanical properties of the substrate will affect the indentation response of the coating system was discussed.

Nonlinear Dynamic Viscoelastic Model for Osteoarthritic Cartilage Indentation Force

2011 ◽  
Author(s):  
A. Vidal-Lesso ◽  
E. Ledesma-Orozco ◽  
R. Lesso-Arroyo ◽  
L. Daza-Benitez
Keyword(s):  
Mechanical Properties ◽  
Soft Tissues ◽  
Mechanical Response ◽  
Viscoelastic Model ◽  
Viscoelastic Behavior ◽  
Indentation Test ◽  
Maxwell Model ◽  
Relaxation Curve ◽  
Geometrical Parameters ◽  
Osteoarthritic Cartilage

Biomechanical properties and dynamic response of soft tissues as articular cartilage remains issues for attention. Currently, linear isotropic models are still used for cartilage analysis in spite of its viscoelastic nature. Therefore, the aim of this study was to propose a nonlinear viscoelastic model for cartilage indentation that combines the geometrical parameters and velocity of the indentation test with the thickness of the sample as well as the mechanical properties of the tissue changing over time due to its viscoelastic behavior. Parameters of the indentation test and mechanical properties as a function of time were performed in Laplace space where the constitutive equation for viscoelasticity and the convolution theorem was applied in addition with the Maxwell model and Hayes et al. model for instantaneous elastic modulus. Results of the models were compared with experimental data of indentation tests on osteoarthritic cartilage of a unicompartmental osteoarthritis cases. The models showed a strong fit for the axial indentation nonlinear force in the loading curve (R2 = 0.992) and a good fit for unloading (R2 = 0.987), while an acceptable fit was observed in the relaxation curve (R2 = 0.967). These models may be used to study the mechanical response of osteoarthritic cartilage to several dynamical and geometrical test conditions.

A Novel Miniaturized Vivaldi Antenna Using Tapered Slot Edge With Resonant Cavity Structure for Ultrawideband Applications

2016 ◽  
Vol 15 ◽  
pp. 1881-1884 ◽  
Author(s):  
Yushun Liu ◽  
Wenjun Zhou ◽  
Shijie Yang ◽  
Weihao Li ◽  
Pengfei Li ◽  
...  
Keyword(s):  
Resonant Cavity ◽  
Cavity Structure ◽  
Vivaldi Antenna

Influence of Experimental Protocols on the Mechanical Properties of the Intervertebral Disc in Unconfined Compression

2011 ◽  
Vol 133 (7) ◽  
Author(s):  
Maximilien Recuerda ◽  
Simon-Pierre Coté ◽  
Isabelle Villemure ◽  
Delphine Périé
Keyword(s):  
Mechanical Properties ◽  
Young’S Modulus ◽  
Nucleus Pulposus ◽  
Annulus Fibrosus ◽  
Young's Modulus ◽  
Viscoelastic Model ◽  
Compression Tests ◽  
Unconfined Compression ◽  
Experimental Conditions ◽  
Experimental Protocols

The lack of standardization in experimental protocols for unconfined compression tests of intervertebral discs (IVD) tissues is a major issue in the quantification of their mechanical properties. Our hypothesis is that the experimental protocols influence the mechanical properties of both annulus fibrosus and nucleus pulposus. IVD extracted from bovine tails were tested in unconfined compression stress-relaxation experiments according to six different protocols, where for each protocol, the initial swelling of the samples and the applied preload were different. The Young’s modulus was calculated from a viscoelastic model, and the permeability from a linear biphasic poroviscoelastic model. Important differences were observed in the prediction of the mechanical properties of the IVD according to the initial experimental conditions, in agreement with our hypothesis. The protocol including an initial swelling, a 5% strain preload, and a 5% strain ramp is the most relevant protocol to test the annulus fibrosus in unconfined compression, and provides a permeability of 5.0 ± 4.2e−14m4/N·s and a Young’s modulus of 7.6 ± 4.7 kPa. The protocol with semi confined swelling and a 5% strain ramp is the most relevant protocol for the nucleus pulposus and provides a permeability of 10.7 ± 3.1 e−14m4/N·s and a Young’s modulus of 6.0 ± 2.5 kPa.

Mechanical properties of Precontraint 1202 S2 based on uniaxial tensile and creep tests

2016 ◽  
Vol 36 (4) ◽  
pp. 254-270 ◽  
Author(s):  
Andrzej Ambroziak ◽  
Paweł Kłosowski
Keyword(s):  
Mechanical Properties ◽  
Polyvinyl Chloride ◽  
Viscoelastic Model ◽  
Tensile Tests ◽  
Woven Fabric ◽  
Uniaxial Tensile ◽  
Creep Tests ◽  
Linear Elastic ◽  
Coated Fabric ◽  
Long Time

The purpose of the paper is the estimation of the polyvinyl chloride – polyester-coated fabric (Precontraint 1202 S2) mechanical properties under uniaxial tensile tests as well as short- and long-time creep tests. The uniaxial tests are the basis of non-linear elastic description while the creep tests are used for the evaluation of the stiffness parameters in time and for the identification of the standard viscoelastic model. The paper also includes a short survey of literature concerning the coated woven fabric description.

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