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Reflective Fourier ptychographic microscopy has much potential for industrial surface inspection due to the ability to overcome the physical limits of the numerical aperture of the optical microscopy. However, the time cost for misalignment calibration and Fourier ptychography (FP) recovery has been a big issue for industrial applications which require fast output. Here, we introduce a misalignment estimation method which is accelerated through the whale optimization algorithm by running in parallel on Central Processing Units (CPUs), named pWOA, to reduce computing time. The proposed method shows more accurate and faster calibration compared to other population-based algorithms, including the parallel genetic algorithm and the parallel particle swarm optimization, and much faster than that of the exhaustive search both in simulations and in real experiments. In addition, this cost-effective technique can address global non-convex optimization problems with heavy loss functions including reflective FP.

We report a facile synthesis of Ce4+ -doped ZrO2/ZnO nanocomposites by a simple ultrasonic-assisted hydrothermal method. The ZrO2/ZnO:x mol% Ce4+ composites were then characterized by x-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, Brunauer–Emmett–Teller (BET), The ζ potential, energy dispersive x-ray spectroscopy (EDS), and elemental mapping, photoluminescence (PL) spectra, x-ray photoelectron spectroscopy (XPS), and UV–Vis diffuse reflectance spectroscopy. The results indicated that the ZrO2/ZnO:x%Ce4+ composites have nanospherical morphology with average particle sizes less than 50 nm and bandgap values of 3.13–3.17 eV. The XPS spectrum confirmed the existence of a Ce4+/Ce3+ pair, which effectively prevents e–/h+ recombination, contributing to the enhanced photocatalytic degradation of organic dyes of photocatalysts. The Ce4+-doped ZrO2/ZnO composites gave the high degradation, 66.88–91.23%, for Rhodamine B under visible-light irradiation. [ABSTRACT FROM AUTHOR]

In this paper, we report on enhancing the biocompatibility properties of Hydroxyapatite-Titanium (HA-Ti) thin films fabricated using the co-sputtering method. By adjusting the HA/Ti ratio through varying the sputtering power of Ti, we obtained HA-Ti thin films with different crystal structures, morphologies, and hydrophilic properties. HA-Ti thin films sputtered at different titanium powers of 80, 100, 120, 140, and 160 W will obtain thin films with larger grain sizes and poorer crystallinity, respectively. However, their hydrophilic properties increase as the contact angle decreases from 78° to 20° degrees. In vitro BHK cell tests indicated that the HA-Ti thin film had excellent biocompatibility. Therefore, this material is suitable for biological applications and has significant potential in medical implant technology.

In this paper, nitrogen‐doped carbon quantum dots (N‐CQDs) are synthesized by the hydrothermal method. N‐CQDs exhibit strong fluorescence, and N‐CQDs are well dispersed in water as well as in various organic solvents. N‐CQDs emit multi‐color fluorescence from blue to red, with wavelengths in the range of 450–650 nm without the need for purification. Furthermore, the fluorescence emission of N‐CQDs was selectively quenched after adding Fe3+ ions. N‐CQDs were used as a nanoprobe for the detection of Fe3+ ions, showing a good linear correlation between the fluorescence emission and the concentration of Fe3+ in the Fe3+ concentration range from 0 to 100 μM. The limit of detection (LOD) was 55.7 μM for Fe3+ in water and 40.2 μM in fetal bovine serum (FBS) samples. The study shows that the synthesized N‐CQDs have low cost and great potential for application in biological analysis. [ABSTRACT FROM AUTHOR]

In recent years, photocatalysis has been used as an environmentally friendly method for the degradation of organic pigments in water. In this study, Ce3+/Ce4+-doped ZrO2/CuO as a mixed semiconductor oxide was successfully prepared by a one-step hydrothermal method. The Ce3+/Ce4+-doped ZrO2/CuO has shown high degradation efficiency of methylene blue (MB), and the maximum degradation percentage was observed to be 94.5% at 180 min under irradiation visible light. The photocatalytic activity increases significantly by doping Ce3+/Ce4+ in ZrO2/CuO for MB degradation. Ce3+/Ce4+ doping is shown to reduce the (e-/h+) recombination rate and improve the charge transfer, leading to enhanced photocatalytic activity of materials. The materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), FTIR, EDS, BET and diffuse reflectance spectroscopy (DRS).

Fault diagnosis is a top-priority task for the health management of manufacturing processes. Deep learning-based methods are widely used to secure high fault diagnosis accuracy. Actually, it is difficult and expensive to collect large-scale data in industrial fields. Several prerequisite problems can be solved using transfer learning for fault diagnosis. Data from the source domain that are different but related to the target domain are used to increase the diagnosis performance of the target domain. However, a negative transfer occurs that degrades diagnosis performance due to the transfer when the discrepancy between and within domains is large. A multi-objective instance weighting-based transfer learning network is proposed to solve this problem and successfully applied to fault diagnosis. The proposed method uses a newly devised multi-objective instance weight to deal with practical situations where domain discrepancy is large. It adjusts the influence of the domain data on model training through two theoretically different indicators. Knowledge transfer is performed differentially by sorting instances similar to the target domain in terms of distribution with useful information for the target task. This domain optimization process maximizes the performance of transfer learning. A case study using an industrial robot and spot-welding testbed is conducted to verify the effectiveness of the proposed technique. The performance and applicability of transfer learning in the proposed method are observed in detail through the same case study as the actual industrial field for comparison. The diagnostic accuracy and robustness are high, even when few data are used. Thus, the proposed technique is a promising tool that can be used for successful fault diagnosis.

C-doped CeO2 nanoparticles were synthesized by hydrothermal method using glucose as carbon source. The structure of the C-doped CeO2 nanoparticles was controlled by the concentration of the glucose precursor. The structure and properties of the C-doped CeO2 nanoparticles were characterized by X-ray diffraction and UV-Vis diffuse reflectance spectroscopy. Microscopic morphology of nanoparticles was characterized by transmission electron microscopy. Photocatalytic activity was assessed by considering the degradation of methylene blue under visible light irradiation. Results show that C-doping significantly improves the photocatalytic activity of CeO2 nanoparticles because of the combination of extending radiation absorption in visible light and the efficient separation of electron–hole pairs. These findings suggest that the present method is useful for controlling the microstructure and dye degradation properties of C-doped CeO2 nanoparticles, which is particularly important for catalyst engineering. [ABSTRACT FROM AUTHOR]

A series of Mn2+‐doped zinc germinate ZGO:xMn2+ (x = 0–0.05) nanorods was synthesized successfully using a hydrothermal method. XRD revealed that crystal phases of the ZGO:xMn2+ were rhombohedral and in the R‐3 space group. The Williamson–Hall equation was also used to explain the strain, nanocrystalline size, and stacking fault. Green LEDs were successfully fabricated by coating ZGO:Mn2+ nanorods onto UV‐LED chips. For high color purity, CIE of the fabricated green LEDs were (0.2404, 0.5428), which made this material a promising candidate for fabrication of UV‐based green LEDs. [ABSTRACT FROM AUTHOR]

ZrO2·Al2O3:Er powder was synthesized by the conventional solid-state reaction method. All the synthesized materials were monoclinic structure of ZrO2 (m-ZrO2) and Al2O3 phases. Scanning electron microscope images showed the spherical particles with diameter of ∼ (30–200) nm. The down-conversion luminescence spectra excited by 380 nm shows near infrared emission band is centered at 1540 nm, corresponding to the transitions of 4I13/2–4I15/2 of Er3+ ions. Under the excitation of a 976 nm laser diode, the up-conversion luminescence spectra of the samples show a red emission band at ∼ 680 nm and a green emission band at ∼ 565 nm, corresponding to the transitions of 4F9/2–4I15/2, 4S3/2–4I15/2, of Er3+ ions, respectively. The dependence of up and down-conversion luminescence properties on dopant concentrations, annealing temperature and Al2O3 concentrations are investigated. These results suggested that this phosphor is a very promising material for light emission and bioimaging. [ABSTRACT FROM AUTHOR]

This paper reports the visible-light photocatalysts and luminescence quenching of ZrO2/AgCl:Eu3+ nanoparticles synthesized by the co-precipitation method as a function of AgCl concentration. XRD analysis indicated the presence of crystalline tetragonal ZrO2 and an AgCl phase. The synthesized ZrO2/AgCl:Eu3+ nanoparticles were observed to have a spherical morphology with diameters of ∼ 20 nm. The photocatalyst with 2.5% mole fractions of AgCl showed effective degradation of methylene blue under visible light with the decolorization percentage reaching ∼ 95% in 180 min. The red emission of Eu3+ in the ZrO2/AgCl:Eu3+ nanoparticles decreased with increasing AgCl mole fraction. Visible-light photocatalysts of ZrO2/AgCl:Eu3+ nanoparticles can be attributed to the presence of AgCl resulting in higher photoexcited charges separation, which can be confirmed by lower luminescence intensity. [ABSTRACT FROM AUTHOR]

Abstract: This article reports on the first attempt of a systematic study on the synthesis of carbon dots (C‐dots) for the potential applications in labeling and detection of molybdenum ion (Mo6+). Carbon dots (C‐dots) were synthesized directly via a simple hydrothermal method using lemon juices as carbon precursor with different temperatures to control the luminescence of C‐dots. The obtained C‐dots had strong green light emission and the ability to use its luminescence properties as probes for Mo6+ detection application, which is based on Mo6+ induced luminescence quenching of C‐dots. This analysis system exhibits strong sensitivity and good selectivity for Mo6+ ion, and a detection limit as low as 20 ppm is achieved. These results suggest that the present C‐dots have potential application in optoelectronic, labeling and luminescent probing of Mo6+ ions. [ABSTRACT FROM AUTHOR]

In this paper, nitrogen-doped carbon quantum dots (N-CQDs) are synthesized by the hydrothermal method. N-CQDs exhibit strong fluorescence, and N-CQDs are well dispersed in water as well as in various organic solvents. N-CQDs emit multi-color fluorescence from blue to red, with wavelengths in the range of 450-650 nm without the need for purification. Furthermore, the fluorescence emission of N-CQDs was selectively quenched after adding Fe 3+ ions. N-CQDs were used as a nanoprobe for the detection of Fe 3+ ions, showing a good linear correlation between the fluorescence emission and the concentration of Fe 3+ in the Fe 3+ concentration range from 0 to 100 μM. The limit of detection (LOD) was 55.7 μM for Fe 3+ in water and 40.2 μM in fetal bovine serum (FBS) samples. The study shows that the synthesized N-CQDs have low cost and great potential for application in biological analysis., (© 2024 John Wiley & Sons Ltd.)

A series of Mn 2+ -doped zinc germinate ZGO:xMn 2+ (x = 0-0.05) nanorods was synthesized successfully using a hydrothermal method. XRD revealed that crystal phases of the ZGO:xMn 2+ were rhombohedral and in the R-3 space group. The Williamson-Hall equation was also used to explain the strain, nanocrystalline size, and stacking fault. Green LEDs were successfully fabricated by coating ZGO:Mn 2+ nanorods onto UV-LED chips. For high color purity, CIE of the fabricated green LEDs were (0.2404, 0.5428), which made this material a promising candidate for fabrication of UV-based green LEDs., (© 2022 John Wiley & Sons, Ltd.)

This article reports on the first attempt of a systematic study on the synthesis of carbon dots (C-dots) for the potential applications in labeling and detection of molybdenum ion (Mo 6+ ). Carbon dots (C-dots) were synthesized directly via a simple hydrothermal method using lemon juices as carbon precursor with different temperatures to control the luminescence of C-dots. The obtained C-dots had strong green light emission and the ability to use its luminescence properties as probes for Mo 6+ detection application, which is based on Mo 6+ induced luminescence quenching of C-dots. This analysis system exhibits strong sensitivity and good selectivity for Mo 6+ ion, and a detection limit as low as 20 ppm is achieved. These results suggest that the present C-dots have potential application in optoelectronic, labeling and luminescent probing of Mo 6+ ions., (Copyright © 2018 John Wiley & Sons, Ltd.)