Applied Physics A最新文献

This study investigates the impact of Laser Shock Peening (LSP) on the biocompatibility and corrosion resistance of SS316L bone staples built using Wire Arc Additive Manufacturing (WAAM). Corrosion tests reveal substantial improvements, with a decrease in corrosion current density from 32.137 × 10^− 4 mA/cm² to 3.50864 × 10^− 4 mA/cm², a reduction in corrosion rate from 3.66754 × 10^− 2 mm/year to 0.400415 × 10^− 2 mm/year. Surface hydrophobicity evaluated through contact angle measurements, demonstrates an increase to 98.85° at the highest LSP intensity of 15.0 GW/cm², indicating improved surface properties critical for biomedical applications. The cytotoxicity analysis and surface morphology indicate that the survival, morphology, and adherence of L929 fibroblast cells improve with increasing LSP intensity.

Present communication holds synthesized PANI-GO functionalized with EDTA (chelating ligand) (PANI-GO-EDTA) which possess octahedral geometry to catch up the heavy metal ions at specific pH. The synthesized composites were applied for detection of Pb (II) ions. The detection was carried out under different experimental conditions using differential pulse stripping voltammtry (DPSV). In this study the materials are studied to assess the repeatability, reproducibility and detection of heavy metal ions at another pH which was 4.5 for Pb ion. These results were discussed in detail which reflects that, present work holds superior sensitivity, selectivity, repeatability compare with earlier reported data.

Improving the power factor is a crucial parameter in enhancing thermoelectric performance, making it essential to find an effective strategy for its enhancement. This study examines n-type Mg₃Sb_1.5Bi₀.5-based thermoelectric materials doped with Zn and Se. Se is added to adjust the carrier concentration, while Zn is introduced into Mg_3.2Sb_1.5Bi_0.49Se_0.01 to manipulate the carrier scattering mechanism. Experimental results indicate a significant increase in carrier mobility from 42.21 cm² V^− 1 s^− 1 to 73.92 cm² V^− 1 s^− 1, leading to a substantial enhancement in electrical conductivity and power factor across the entire temperature range under investigation. Additionally, due to reduced lattice thermal conductivity resulting from the introduction of efficient phonon scattering centers in the Zn and Se co-doped sample, Mg_3.18Zn_0.02Sb_1.5Bi_0.49Se_0.01 attains a maximum ZT value of 1.77 at 623 K, resulting in a notable average ZT ≈ 1.24 over the temperature range of 300 to 673 K. Given its cost-effectiveness and low toxicity, this material is anticipated to replace the commercially available n-type Bi₂Te₃-based thermoelectric materials commonly used at moderate and low temperatures.

The effects of magnetic field on magnetoelectric coupling, dielectric and transport properties of 0.5LaFeO₃-0.5PbZr_0.58Ti_0.42O₃ nanocomposites are investigated at room temperature. The maximum value of magnetoelectric coupling is found to ~ 1.3 and ~ 0.2 mV/cm-Oe, which approves the multiferroic in nature, it may agree with the strain mediated piezomagnetic phase and magnetocapacitance property of the material. The observed magneto-capacitance (~ 23%) at lower frequency attributes to the interface or space charge polarization of sample as the Maxwell-Wagner effect. The classical electrodynamics effect is the main reason for the magnetoimpedance behaviour (~ 50%) at room temperature. The involvement of grain and grain boundaries effect may takes dominating role on conductivity, which is illustrated from the impedance and modulus diagrams assigned the non-Debye type phenomena. The relaxation frequency is changed by an application of magnetic field corroborating the spin dependent electrical transport mechanism at the grain boundaries. The decreasing nature of ac conductivity with applied magnetic field characterizes the presence of defect states in interfaces of LaFeO₃ and PbZr_0.58Ti_0.42O₃ grains. Also, it may agree to the occurance of strain mediation of piezomagnetic phase of the system. Also this composite may corresponds to the occurance of strain mediation of piezomagnetic phase and magnetodielectric effect.

A one-step potentiostatic electrochemical deposition technique was used to deposit tin sulfide (SnS) thin films onto an ITO-coated glass substrate at room temperature. The present work aims to investigate the effect of the electrodeposition time on various physical properties of SnS semiconductors. The emphasis will be placed on determining the time necessary to cover the entire surface of the substrate with a first layer of SnS and on studying the effect of the conductivity of this first layer on the further growth of the SnS layers. Different electrodeposition times were considered, and the obtained samples were examined using appropriate techniques. X-ray diffraction reveals the orthorhombic polycrystalline nature for all samples and shows that the intensity of pure SnS peaks increases with increasing deposition time. Beyond 40 min of electrodeposition, XRD analysis shows the appearance of SnS secondary phases such as SnS₂ and Sn₂S₃. Raman characterization unveils a behavior change detected from 40 min of electrodeposition and confirms the presence of peaks characteristic of the SnS, Sn₂S₃, and SnS₂ phases. SEM images reveal that the first SnS layer completely covers the substrate surface between 30- and 40-min electrodeposition. EDX Analysis has shown that to achieve SnS layer stoichiometry, it is necessary to deposit SnS on substrates with high conductivity. Optical characterization confirms that transmittance decreases with increasing deposition time reflecting an increase in SnS layer thickness. The band gaps were identified as direct ones with energies around 1.3 eV for all samples and correlated both to the thickness of the layers and/or to the crystallite size.

In this study, photon interaction parameters such as radiation protection efficiency (RPE), total mass attenuation coefficient (μ/ρ), linear attenuation coefficients (μ), half value layers (HVL), tenth value layers (TVL), mean free paths (MFP), effective atomic numbers (Z_Eff) and effective electron densities (N_Eff) were experimentally investigated for the BCZrB-0, BCZrB-10, BCZrB-20, BCZrB-30, BCZrB-40 and BCZrB-50 in the energy range from 59.5 keV to 1332.5 keV. In the experiment, HPGe detector and ²⁴¹Am (59.5 keV), ¹³³Ba (81 keV, 276.4 keV, 302.9 keV, 356 keV and 383.9 keV), ²²Na (511 keV and 1274.5 keV), ¹³⁷Cs (661.7 keV), and ⁶⁰Co (1173.2 keV and 1332.5 keV) radioactive point sources were used. Experimental results compared with results of the WinXCOM, GEANT4 simulation code and FLUKA simulation code. Energy absorption build-up factors (EABF) and exposure build-up factors (EBF) were calculated with G-P fitting method in the energy region 0.015 MeV ≤ E ≤ 15 MeV. Kerma relative to air values were investigated in the energy region 0.001 MeV ≤ E ≤ 20 MeV. Effective removal cross section, total macroscopic cross section and number of transmitted neutron values were defined for composites. The agreement between experimental and WinXCOM program, between experimental and GEANT 4 simulation codes and between experimental and FLUKA simulation codes of gamma-ray interaction parameters are < 5.1%, < 6.5% and < 5%, respectively. All of the results are compatible with each other and BCZrB-50 is a good gamma-ray radiation absorber in the studied composites and BCZrB-0 is the best neutron absorber in the studied composites.

In this work, the properties of lead-free piezoelectric K_0.5Na_0.5NbO₃ (KNN) were enhanced by antimony (Sb) doping on the B-site using a solid-state reaction method. XRD and Raman analysis confirmed phase purity, showing an orthorhombic structure. X-ray diffraction patterns were fitted using FullProf to determine lattice parameters, revealing reduced bond angles and lengths in Sb-doped KNN (KNNS). The dielectric properties showed a phase transition in pure KNN at 185 °C (orthorhombic to tetragonal) and 380 °C (tetragonal to cubic), while KNNS exhibited relaxer ferroelectric behaviour. KNNS displayed enhanced ferroelectricity (2P_s = 26.2 μC/cm²) and low leakage current (4.17 nA-cm⁻²). KNNS also demonstrated superior energy harvesting, producing 25.2 V and a power density of 7.71 mW-cm⁻² under finger tapping, a 280% improvement over pure KNN. The study highlights the benefits of Sb doping in improving the electrical properties and Curie temperature of KNN, as well as its successful application in energy harvesting and ultrasonic testing of aluminium alloy specimens.

In this paper, we have proposed a graphene-based dual symmetric bound states in the continuum (BIC) metasurface. On an all-graphene platform, we have shown that by breaking the symmetry in two ways, one can simultaneously access dual quasi-BIC (Q-BIC) spectra. The unit cell of the metasurface consists of the graphene etch patterned circles of equal radius on a dielectric substrate. The placement of the pattern is such that the structure is symmetric. By perturbing the radius of the circle at these symmetric positions, the asymmetry is introduced to access the first Q-BIC. Another way of accessing the Q-BIC spectra is to perturb the symmetric positions, maintaining the equal radii of the etched circles. Combining these two strategies, one can access the dual QBIC spectra based on the wavelength range of interest. Moreover, graphene is tunable with the control of its chemical potential. We have demonstrated our tunable structure at the MID-IR region in the transmission mode of operation. All the device dimensions are in the sub-wavelength range. The Q-factor of these plasmonic Q-BIC transmission dips has moderate values that hold wide prospects in sensing applications. For our proposed structure, we have shown application in nanoscale sensing of hazardous solvents like nitrobenzene and hazardous gases like methane, considering the experimental dispersion data. A minimum limit of detection (LOD) of 0.025 RIU and 0.0068 RIU has been reported for nitrobenzene and methane.

High-precision Ni-based alloy components are widely used in aerospace and other advanced applications. However, when machining accuracy reaches the micrometer scale or higher, the microstructure of the material must be considered. To uncover its microscopic grinding mechanisms, we employed molecular dynamics to study the grinding behavior of the alloy and its constituent phases. The results indicate that, compared to the γ single crystal (SC), the γ’ single crystal (SC) exhibits enhanced interatomic bonding due to the incorporation of Al atoms. Consequently, it experiences the highest subsurface residual stress and grinding temperature, leading to poorer grinding performance. Furthermore, under external forces, its activated slip surfaces are fewer, and the motion of dislocations is more restricted. In contrast, the two-phase γ/γ’ Ni-based SC combines the properties of both phases, demonstrating superior grinding performance. The presence of grain boundaries further impedes dislocation motion and leads to properties distinct from those of its constituent SCs.

Flexible Raman-enhanced substrates possess the advantages of good adsorbability and extensibility, which are particularly beneficial for the effective analyses of target molecules on complex or irregular surfaces. Here, we reported a large-scale, flexible and transparent surface-enhanced Raman scattering (SERS) substrate. This Ag NWs/M-CDG/PDMS substrate was composed of a modified compact disc grating polydimethylsiloxane (M-CDG/PDMS) film decorated with silver nanowires (Ag NWs) through a self-assembly process. The surface of the grating PDMS film was modified with 3-aminopropyltriethoxysilane (APTES) to create a hydrophilic layer. The contact angle of the APTES-modified PDMS film decreased from 105° to 66°, indicating improved hydrophilicity compared to the unmodified film. Thiram was chosen as a probe molecule to evaluate the SERS performance of the prepared substrates. It was found that the substrate displayed high SERS sensitivity with a detection limit for thiram as low as 10^− 8 M, and good uniformity, evidenced by RSD (relative standard deviation) values of 8.7% and 9.9%. Moreover, the fabricated substrate showed good mechanical stability and SERS enhancement effects even under backlight illumination, making it suitable for in-situ SERS detection on curved surfaces. The Ag NWs/M-CDG/PDMS flexible substrate also demonstrated the advantages of anti-corrosion, mixed detection capabilities, a wide operating temperature range, and the ability to perform vapor phase detection. In summary, the developed Ag NWs/M-CDG/PDMS substrate had great potential for practical applications in detection technologies.