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Cancer, the world's second most common cause of death, has seen a recent surge in mortality. Harnessing biomarkers for diagnosis hold promise for early cancer detection and treatment. Biosensors, particularly using Surface-Plasmon-Resonance (SPR) technology for label-free detection, are key to this strategy. This research introduces an innovative biosensor concept based on SPR technology, recognized for its exceptional sensitivity in detecting cancer cells. The biosensor features a unique layer of Gold, with an enhanced hexagonal lattice design featuring air holes. Through advanced numerical simulations employing the Finite Element Model, refractive index (RI) changes related to malignancy were observed via wavelength and amplitude-based interrogation methods. Notably, the biosensor demonstrated a highest sensitivity measuring 7142.86 nm/RIU (nm per RIU) during spectral interrogation for MCF7 cells, along with a sensitivity of − 4220.99 per unit of RIU amplitude-based interrogation method for HeLa cells. Additionally, this biosensor achieved a significant resolution of 3.33 × 10–5 RIU for Basal cells. In summary, this study unveils a cutting-edge biosensor rooted in SPR technology, showcasing high sensitivity and efficacy in detecting cancer cells. Rigorous numerical analysis underscores its potential for early cancer detection and precise diagnostics. [ABSTRACT FROM AUTHOR]

The development of new advanced functionalities, miniaturization, and the aim of obtaining optimized performance in electronic devices significantly impacts their electromagnetic compatibility (EMC). As electronic components become more densely packed on a printed circuit board (PCB), unintended coupling between components can cause electromagnetic interference (EMI). These requirements result in design restrictions that make using a board level shield (BLS) essential in reducing intra-system EMI in PCB designs. This contribution focuses on studying and characterizing a BLS solution based on combining a noise suppression sheet (NSS) with an aluminum layer to reduce intra-system EMI coupling. This hybrid solution has the advantage of providing a shielding option that does not require any electronic redesign. It does not need a footprint or a ground connection as it can be affixed over the EMI source. The solution is expected to provide higher attenuation levels than using only an NSS by combining the absorbing properties of the magnetic material and the loss mechanism of the metal. In order to verify the effectiveness of the hybrid BLS proposed solution, the magnetic near-field emissions of an EMI source are analyzed in this study. The experimental measurements and simulated results demonstrate a significant increase (51.6 dB at 1 GHz) in the shielding effectiveness (SE) provided by the proposed solution compared to a conventional NSS. [ABSTRACT FROM AUTHOR]

Pulsed eddy current (PEC) is an advanced non-destructive testing (NDT) technique based on the electromagnetic principle. The excitation consists of a broad frequency spectrum for detection of defects in various depths of specimens. This paper details out the experimental and simulation investigations in determining the correlation between PEC signals and conductivity of different nonferromagnetic materials. The finite element method (FEM) simulation work provided understanding on the underlying phenomena by visualising the eddy current density and magnetic field distribution in specimens with varying conductivity values. The FEM results show that conductivity affects the induced current density within the specimens. Specimens with high conductivities generate high current density within the specimen, which increases the net magnetic field acquired from the specimen. In addition, the results obtained from the conductivity experiments demonstrated good agreement with that of the FEM simulation. Both approaches generate increment in the amplitude of the net magnetic field acquired from specimens with different conductivity values. [ABSTRACT FROM AUTHOR]

Large deformation stress response characteristics of hydrocolloid mixture gel systems were investigated based on texture and rheological measurements. Agarose and xanthan mixtures at different ratios (1:0, 0.75:0.25, and 0.5:0.5) were chosen as the model systems. A decrease in failure stress from 2.65 to 1.82 MPa and an increase in failure strain from 0.08 to 0.13 with higher xanthan ratios were obtained based on the ring tensile test, indicating that xanthan molecules could improve the flexibility of the agarose network. The gels showed severe water loss by compression, particularly for the pure agarose gel (6.74%). Compared to the compression test, the gels presented low water loss after the ring tensile test (<1.3%) indicating that the ring tensile test could calculate the correct stress–strain relationship. Digital image correlation (DIC) and numerical simulation revealed that agarose-xanthan gel systems possess a deformation behavior with homogeneous strain distribution before failure. Elastic and viscous Lissajous–Bowditch curves from the large amplitude oscillatory shear (LAOS) measurement at different strains and frequencies elucidated that the agarose-xanthan gel was dominated by the agarose structure with a similar magnitude of elasticity at a low frequency. The large deformation approach from this study has great potential for elucidating and understanding the structure of food and biopolymer gels. [ABSTRACT FROM AUTHOR]

Temperature sensors have been widely applied in daily life and production, but little attention has been paid to the research on temperature sensors based on surface plasmon resonance (SPR) sensors. Therefore, an SPR temperature sensor with a triple structure of titanium dioxide (TiO2) film, gold (Au) film, and TiO2 nanorods is proposed in this article. By optimizing the thickness and structure of TiO2 film and nanorods and Au film, it is found that the sensitivity of the SPR temperature sensor can achieve 6038.53 nm/RIU and the detection temperature sensitivity is −2.40 nm/°C. According to the results, the sensitivity of the optimized sensor is 77.81% higher than that of the sensor with pure Au film, which is attributed to the TiO2(film)-Au-TiO2(nanorods) structure. Moreover, there is a good linear correlation (greater than 0.99) between temperature and resonance wavelength in the range from 0 °C to 60 °C, which can ensure the detection resolution. The high sensitivity, FOM, and detection resolution indicate that the proposed SPR sensor has a promising application in temperature monitoring. [ABSTRACT FROM AUTHOR]

Thin AlN piezoelectric layers have been deposited on high resistivity Si and glass substrates by reactive RF magnetron sputtering, in order to manufacture one-port gigahertz operating surface acoustic wave (SAW)-type resonators to be used as temperature sensors. The growth morphology surface topography, crystallographic structure, and crystalline quality of the AlN layers have been analyzed. Advanced nanolithographic techniques have been used to manufacture structures having interdigitated transducers with fingers and finger interdigit spacing width in the range of 250–170 nm. High resonance frequency ensures the increase of the sensitivity, but also of its normalized value, the temperature coefficient of frequency (TCF). The resonance frequency shift versus temperature has been measured in the −267°C−+150°C temperature range, using a cryostat setup adapted for on wafer microwave measurements up to 50 GHz. The sensitivity and the TCF were determined in the 25 °C–150 °C temperature range. [ABSTRACT FROM AUTHOR]

Introduction: The radiofrequency ablation (RFA) of liver cancer is a desirable treatment option, as it is minimally invasive. An accurate numerical simulation can greatly help physicians better plan their surgical protocols. Previously, the displacement current in the RFA process was considered negligible, and therefore RFA simulation was modeled as a direct current (DC) system instead of an alternating current (AC) system. Our study investigated the hypothesis that the displacement current in the RFA process should not always be considered negligible. Methods: AC measurements of ex vivo bovine liver ablation were performed, and numerical simulations were also conducted to test the hypothesis that the relative permittivity would significantly decrease after the liver tissue reached a high temperature. Results: The displacement current was observed to be a sizable fraction of the conduction current, especially before the onset of the first pause. The simulation results indicated that the relative permittivity is likely to decrease to several hundred or lower at elevated temperatures. Conclusions: Our study results suggest that the DC model may be inadequate, especially before the first roll-off and that additional information could be available during RFA treatment by considering the AC nature of RFA, which could lead to improved numerical simulation. Additional measurements of tissue parameters are needed to reach the full potential of the AC model for further development of ablation control. [ABSTRACT FROM AUTHOR]

In this work, the effects of extreme thermal fluctuations on the reliability of solder joints were investigated. For this purpose, the solder joints in insulated-gate bipolar transistor (IGBT) devices were exposed to the conventional thermal cycling and the thermal shock cycling (TSC) tests. The finite element method (FEM) simulation results indicated that the accumulated creep energy in solder layer is much higher under the TSC process. Moreover, the stress triaxiality, as the indicator of damage initiation, is more concentrated in the TSC-exposed sample. It is believed that the higher heating and cooling rates along with the higher peak temperatures lead to the damage susceptibility of solder joints under TSC process. The experimental results confirm that the void formation and growth significantly increases in the TSC-exposed sample, which is consistent with the simulation outcomes. Moreover, the shear test reveals that the ultimate strength of sample under the thermal shocking severely decreases which is due to the void growth and the intensified elemental heterogeneity. [ABSTRACT FROM AUTHOR]

The first European superconducting winding pack (WP) and the first set of coil cases [toroidal field coil cases (TFCC)] for ITER are going to be delivered in 2017. The TFCC are steel structures that provide structural integrity to the WP, contribute to neutron shielding capacity, provide support to operating forces, and offer interface connections with the rest of the ITER machine. The TFCC assembly is formed by four main parts: two sectors with U-shaped section and two closure plates, which, after being welded together, enclose the WP. Each TFCC weights about 150 t and presents a wall thickness from 60 to 120 mm. The presence of distortions when welding such thick structures is particularly problematic in these components, which require tight tolerances and include several interfaces with other parts of the machine. In order to compensate the distortions, extra material is present in the critical areas to allow postwelding machining. The amount of extra material has to be optimized to reduce machining time and therefore the cost of the manufacturing. Thus, the evaluation of the welding-caused distortions is essential in order to confirm the extra-material strategy. In this scenario, an experimental and simulation campaign has been set up to predict the deformation of the TFCC during welding. First, welding coupons were welded in representative configurations. Then, these data were used to build a preliminary finite element method (FEM) model tool, using ANSYS software, which was then benchmarked against a "blind test" coupon and three TFCC-like mock-ups of 1-m length. Finally, a full FEM model was constructed using the previous outputs and is currently under assessment to predict the deformation of the TFCC during the welding process. This paper presents the numerical and experimental activities carried out so far, being EnginSoft S.p.A. the developer of FEM models, SIMIC S.p.A. the responsible of welding processes and data acquisition, and Fusion for Energy the contractual and technical supervisor. [ABSTRACT FROM AUTHOR]

In this paper, a novel technique is proposed to improve the wireless power transfer efficiency for downhole logging environment. The method applies a soft ferrite layer on the oil pipe so that the magnetic coupling between the transmitter and the receiver is greatly enhanced. Power transfer efficiency is calculated via electromagnetic simulation using the finite element method. A prototype was built to demonstrate the effectiveness of the technique. [ABSTRACT FROM AUTHOR]

This study reports the controllable surface roughening of Au-Ag alloy nanoplates via the galvanic replacement reaction between single-crystalline triangular Ag nanoplates and HAuCl in an aqueous medium. With a combination of experimental evidence and finite element method (FEM) simulations, improved electromagnetic field (E-field) enhancement around the surface-roughened Au-Ag nanoplates and tunable light absorption in the near-infrared (NIR) region (~800-1,400 nm) are achieved by the synergistic effects of the localized surface plasmon resonance (LSPR) from the maintained triangular shape, the controllable Au-Ag alloy composition, and the increased surface roughness. The NIR light extinction enables an active photothermal effect as well as a high photothermal conversion efficiency (78.5%). The well-maintained triangular shape, surface-roughened evolutions of both micro- and nanostructures, and tunable NIR surface plasmon resonance effect enable potential applications of the Au-Ag alloy nanoplates in surface-enhanced Raman spectroscopic detection of biomolecules through 785-nm laser excitation. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

This study aims at investigating the effect of cutting speed, feed rate and depth of cut on surface roughness, microstructure of machined part and tool wear in dry rough turning of Ni superalloy Inconel-718 using PVD coated (TiAlN + TiN) carbide tool inserts. Taguchi's method for optimization of machining parameters (vc = 40-60 m/min, f = 0.05-0.1 mm/rev and d = 0.25-0.5 mm) was used. A Finite Element (FE) model of the tool geometry was developed in order to understand the trends of deformation and shear stress induced due to mechanical loads during orthogonal machining. Regression equations versus the cutting parameters were obtained for surface finish and tool wear. Changes in microstructure were found to be negligible. The investigation suggested that for PVD coated (TiAlN + TiN) carbide tool inserts, cutting speed of 60 m/min, feed rate of 0.05 mm/rev and depth of cut of 0.5 mm were optimum for producing the best cutting results. [ABSTRACT FROM AUTHOR]

Sensitivity is one of the most important parameters to put in the foreground in all sensing applications. Its increase is therefore an ongoing challenge, particularly for surface acoustic wave (SAW) sensors. Herein, finite element method (FEM) simulation using COMSOL Multiphysics software is first used to simulate the physical and electrical properties of SAW delay line. Results indicate that 2D configuration permits to accurately obtain all pertinent parameters, as in 3D simulation, with very substantial time saving. A good agreement between calculation and experiment, in terms of transfer functions (S21 spectra), was also shown to evaluate the dependence of the SAW sensors sensitivity on the operating frequency; 2D simulations have been conducted on 104 MHz and 208 MHz delay lines, coated with a polyisobutylene (PIB) as sensitive layer to dichloromethane (DCM). A fourfold increase in sensitivity was obtained by doubling frequency. Both sensors were then realized and tested as chem-sensors to detect zinc ions in liquid media. 9-{[4-({[4-(9anthrylmethoxy)phenyl]sulfanyl} methyl)]methyl] anthracene (TDP-AN) was selected as the sensing layer. Results show a comparable response curves for both designed sensors, in terms of limit of detection and dissociation constants Kd values. On the other hand, experimental sensitivity values were of the order of [7.0 ± 2.8] × 108 [°/M] and [16.0 ± 7.6] × 108 [°/M] for 104 MHz and 208 MHz sensors, respectively, confirming that the sensitivity increases with frequency. [ABSTRACT FROM AUTHOR]

Controlling the heat transport and thermal conductivity through a material is of prime importance for thermoelectric applications. Phononic crystals, which are a nanostructured array of specially designed pores, can suppress heat transportation owing to the phonon wave interference, resulting in bandgap formation in their band structure. To control heat phonon propagation in thermoelectric devices, phononic crystals with a bandgap in the THz regime are desirable. In this study, we carried out simulation on snowflake shaped phononic crystal and obtained several phononic bandgaps in the THz regime, with the highest being at ≈2 THz. The phononic bandgap position and the width of the bandgap were found to be tunable by varying the neck-length of the snowflake structure. A unique bandgap map computed by varying the neck-length continuously provides enormous amounts of information as to the size and position of the phononic bandgap for various pore dimensions. We have also carried out transmission spectrum analysis and found good agreement with the band structure calculations. The pressure map visualized at various frequencies validates the effectiveness of snowflake shaped nano-pores in suppressing the phonons partially or completely, depending on the transmission probabilities. [ABSTRACT FROM AUTHOR]

Controlling the heat transport and thermal conductivity through a material is of prime importance for thermoelectric applications. Phononic crystals, which are a nanostructured array of specially designed pores, can suppress heat transportation owing to the phonon wave interference, resulting in bandgap formation in their band structure. To control heat phonon propagation in thermoelectric devices, phononic crystals with a bandgap in the THz regime are desirable. In this study, we carried out simulation on snowflake shaped phononic crystal and obtained several phononic bandgaps in the THz regime, with the highest being at ≈2 THz. The phononic bandgap position and the width of the bandgap were found to be tunable by varying the neck-length of the snowflake structure. A unique bandgap map computed by varying the neck-length continuously provides enormous amounts of information as to the size and position of the phononic bandgap for various pore dimensions. We have also carried out transmission spectrum analysis and found good agreement with the band structure calculations. The pressure map visualized at various frequencies validates the effectiveness of snowflake shaped nano-pores in suppressing the phonons partially or completely, depending on the transmission probabilities. [ABSTRACT FROM AUTHOR]