Cancer is a leading cause of death worldwide, characterized by uncontrolled cell growth affecting various tissues and organs. Early detection is crucial to reduce mortality and treatment costs. This study proposes a highly sensitive perovskite one-dimensional (1D) defective photonic crystal (PC) biosensor designed to detect cancer cells by exploiting shifts in resonant modes caused by differences in refractive indices (RI) between healthy and malignant cells infiltrating the bio-cavity layers. The sensor structure consists of alternating layers of SrTiO 3 and bio-cavities filled with cancerous or healthy cells with a central defect layer. Using the transfer matrix method (TMM), the transmittance spectra and resonant peak shifts are analysed under varying parameters such as defect layer thickness, incidence angle, and number of periods to optimize sensitivity and quality factor. Introducing SiO 2 as the defect layer enhances sensitivity due to improved light-matter interaction. The optimized sensor achieves a sensitivity of up to 930 nm/RIU, a high quality factor of [Formula: see text], and a low detection limit [Formula: see text], demonstrating its potential as a cost-effective, precise, and rapid tool for biomedical refractive-index based cancer discrimination applications.
Precision piercing of nickel-based superalloys remains challenging because abrasive waterjet (AWJ) penetration can produce non-uniform entry–exit geometry and kerf taper, particularly in deep micro-hole applications. This study systematically investigates the formation, geometrical accuracy, and surface morphology of AWJ-pierced holes in 12-mm-thick Inconel 718 using silicon carbide (SiC) abrasives. The influence of key process parameters, namely abrasive mesh size ([Formula: see text]), abrasive jet pressure ([Formula: see text]), stand-off distance ([Formula: see text]), and machining time ([Formula: see text]), was systematically examined through a full experimental design comprising 96 trials. Hole quality was evaluated from the top and bottom diameters and the resulting kerf angle using a calibrated video measuring system, while scanning electron microscopy was employed to elucidate the associated material-removal mechanisms. The results demonstrate that machining time is the dominant parameter governing kerf-angle formation, accounting for 79.632% of the total variation, followed by pressure with a 3.645% contribution; abrasive mesh size and stand-off distance exhibit comparatively minor effects within the investigated ranges. Kerf angle decreased from 0.91–1.60 ∘ at 40[Formula: see text]s to 0.03–0.59 ∘ at 60[Formula: see text]s, while the lowest measured kerf angle of 0.02 ∘ was achieved at 80[Formula: see text]s. The optimum condition was identified as 120# SiC, 100 MPa jet pressure, 3[Formula: see text]mm stand-off distance, and 80 s machining time, producing a near-cylindrical hole profile with top and bottom diameters of 1.83 and 1.82[Formula: see text]mm, respectively. Repeatability assessment at the optimum condition yielded a standard deviation of 0.001 ∘ and a 95% confidence interval of [Formula: see text], indicating good experimental repeatability under the selected optimum condition. SEM observations indicate predominantly ductile erosion characterized by micro-cutting, ploughing, particle embedment, and localized plastic deformation, with possible localized brittle damage under high-energy impacts.
In the context of low-carbon and energy-efficient manufacturing, this study investigated laser remelting of 35CrMo/Fe45 cladding layers to improve surface quality and microhardness while reducing energy consumption. Laser power, scanning speed, and overlap ratio were selected as the main process parameters, while surface roughness, microhardness, and electrical energy consumption during laser-on processing were taken as the optimization objectives. Based on the experimental data obtained using an enhanced Latin hypercube sampling design, a surrogate model was constructed. The multi-objective exponential distribution optimizer (MOEDO) was then used to generate a Pareto-optimal solution set, from which CRITIC-TOPSIS selected the optimal process parameters. Relative to the as-clad condition, the surface roughness of the cladding layer decreased from 8.56 μm to 0.789 μm, while the microhardness increased from 536 HV0.5 to 625.3 HV0.5. Compared with the reference condition, the optimized process reduced surface roughness by 39.6%, increased microhardness by 31.5%, and reduced electrical energy consumption during laser-on processing by 55.7%. The proposed approach provides a practical basis for balancing surface-quality improvement, hardness enhancement, and energy saving in energy-efficient laser remelting of cladding layers.
This paper presents the design, analysis, fabrication and testing of an ultra-thin narrow-band metamaterial (MM) absorber tailored for improving the sensitivity of pressure sensors. The proposed resonator achieves an impressive absorption characteristic of 99.85% at 5.355[Formula: see text]GHz. A prototype is fabricated using standard PCB technology and experimental validation is conducted in an anechoic chamber to verify the simulated results. The sensor design incorporates an analytical diaphragm layer between two substrates, demonstrating the ability to detect minor shifts in pressure with an average sensitivity of 2080[Formula: see text]MHz/mm. Key sensor characteristics include a high quality factor of 49.28 and a substantial Figure of Merit of 43.45. The linear behavior of the sensor is quantified through curve fitting, showing good agreement with the simulated sensitivity. The designed MM absorber exhibits merit such as perfect absorptivity, linear sensitivity, narrow bandwidth, high Q-factor, and a substantial Figure of Merit, making it a strong contender for pressure sensing applications.
In this study, Co-base Stellite-6 composite is applied onto SS316L steel using laser cladding. The grains in the cladding are ten times smaller than those in the steel substrate, forming a dendritic structure with a thin layer in between that is 1-2 mu m thick. X-ray diffraction (XRD) analysis identified W2C and Cr7C3 carbides in the cladding, which has more carbide peaks than the original powder. The cladding reaches a maximum nanohardness of 2GPa at a load of 4000 mu N, which decreases to 1.1GPa at 10,000 mu N. In comparison, the substrate's hardness is 1.5 GPa at 4000 mu N and drops to 1 GPa at 10,000 mu N. The elastic modulus ranges from 24.00GPa to 28.41GPa at 4000 mu N, with lower values at higher loads. Wear behavior is examined in three orientations at the intersection: 0 degrees, 45 degrees, and 90 degrees to the cladding direction. The wear depths measured at these angles are 350 +/- 10 nm, 460 +/- 10 nm, and 640 +/- 10 nm, respectively. The lowest wear depth is found at 0 degrees orientation wear track. Compared to the 0 degrees orientation wear track, the 45 degrees and 90 degrees orientation wear tracks suffer from higher wear depth. The shallow slope of wear depth occurred at 0 degrees and 45 degrees orientations, whereas the steeper slope of wear depth is found at 90 degrees orientation wear track. The slender shape of worn-out material forms at 0 degrees orientation wear track, whereas the patch shape worn-out material formed at 45 degrees and 90 degrees orientations wear track. The 0 degrees and 45 degrees orientations wear track follows the linear frictional path. The friction of the 90 degrees orientation wear track decreases from a linear to a parabolic path at the intersection region. The continuous, slender, worn-out material with a linear frictional path forms a wear track at 0 degrees orientation. The patch-shaped worn-out material with a linear-parabolic frictional path forms a wear track at 90 degrees orientation.
