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Keywords = optical design

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16 pages, 1675 KiB  
Article
Long-Term Effectiveness of a Monofocal Intraocular Lens (IOL) Enhanced for Intermediate Vision: A 5-Year Follow-Up Study
by Rita Mencucci, Giovanni Romualdi, Alberto Carnicci, Fabio Panini, Matilde Buzzi and Fabrizio Giansanti
J. Clin. Med. 2025, 14(16), 5831; https://doi.org/10.3390/jcm14165831 - 18 Aug 2025
Abstract
Background/Objectives: The Tecnis Eyhance is an enhanced monofocal intraocular lens (IOL) designed to improve intermediate vision without compromising distance clarity or increasing the incidence of photic phenomena. Although short-term results have been encouraging, long-term data remain limited. This study presents the 5-year [...] Read more.
Background/Objectives: The Tecnis Eyhance is an enhanced monofocal intraocular lens (IOL) designed to improve intermediate vision without compromising distance clarity or increasing the incidence of photic phenomena. Although short-term results have been encouraging, long-term data remain limited. This study presents the 5-year follow-up of a previously published 6-month clinical evaluation, aiming to assess the stability of visual, optical, and patient-reported outcomes over time. Methods: A single-center retrospective study of 18 patients (36 eyes) undergoing bilateral Tecnis Eyhance IOL implantation was conducted. The same cohort from the original 6-month study was re-evaluated after a mean follow-up of 5 years. Visual acuity (distance, intermediate, near), defocus curves, contrast sensitivity, optical quality, effective lens position (ELP), halo size, and patient-reported measures were assessed. Results: Visual acuity remained stable across all distances, with binocular uncorrected intermediate visual acuity (UIVA) ≤ 0.2 logMAR in all patients. No significant changes were observed in optical quality parameters or contrast sensitivity. ELP remained consistent over time (p = 0.298), and posterior capsule opacification (PCO) requiring Nd:YAG capsulotomy developed in 5% of the eyes. Halo size was mild, and subjective glare perception did not increase. Spectacle independence remained high for distance (100%) and intermediate (more than 75%) tasks. Conclusions: This 5-year follow-up study confirms the long-term stability and effectiveness of the Tecnis Eyhance IOL. These findings support its long-term use as a stable monofocal IOL with enhanced intermediate function. Full article
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22 pages, 3265 KiB  
Article
A Novel Multi-Core Parallel Current Differential Sensing Approach for Tethered UAV Power Cable Break Detection
by Ziqiao Chen, Zifeng Luo, Ziyan Wang, Zhou Huang, Yongkang He, Zhiheng Wen, Yuanjun Ding and Zhengwang Xu
Sensors 2025, 25(16), 5112; https://doi.org/10.3390/s25165112 - 18 Aug 2025
Abstract
Tethered unmanned aerial vehicles (UAVs) operating in terrestrial environments face critical safety challenges from power cable breaks, yet existing solutions—including fiber optic sensing (cost > USD 20,000) and impedance analysis (35% payload increase)—suffer from high cost or heavy weight. This study proposes a [...] Read more.
Tethered unmanned aerial vehicles (UAVs) operating in terrestrial environments face critical safety challenges from power cable breaks, yet existing solutions—including fiber optic sensing (cost > USD 20,000) and impedance analysis (35% payload increase)—suffer from high cost or heavy weight. This study proposes a dual innovation: a real-time break detection method and a low-cost multi-core parallel sensing system design based on ACS712 Hall sensors, achieving high detection accuracy (100% with zero false positives in tests). Unlike conventional techniques, the approach leverages current differential (ΔI) monitoring across parallel cores, triggering alarms when ΔI exceeds Irate/2 (e.g., 0.3 A for 0.6 A rated current), corresponding to a voltage deviation ≥ 110 mV (normal baseline ≤ 3 mV). The core innovation lies in the integrated sensing system design: by optimizing the parallel deployment of ACS712 sensors and LMV324-based differential circuits, the solution reduces hardware cost to USD 3 (99.99% lower than fiber optic systems), payload by 18%, and power consumption by 23% compared to traditional methods. Post-fault cable temperatures remain ≤56 °C, ensuring safety margins. The 4-core architecture enhances mean time between failures (MTBF) by 83% over traditional systems, establishing a new paradigm for low-cost, high-reliability sensing systems in terrestrial tethered UAV cable health monitoring. Preliminary theoretical analysis suggests potential extensibility to underwater scenarios with further environmental hardening. Full article
(This article belongs to the Section Sensor Networks)
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24 pages, 3567 KiB  
Article
Evaluation of Biocontrol Measures to Reduce Bacterial Load and Healthcare-Associated Infections
by Anna Vareschi, Salvatore Calogero Gaglio, Kevin Dervishi, Arianna Minoia, Giorgia Zanella, Lorenzo Lucchi, Elena Serena, Concepcion Jimenez-Lopez, Francesca Cristiana Piritore, Mirko Meneghel, Donato Zipeto, Diana Madalina Gaboreanu, Ilda Czobor Barbu, Mariana Carmen Chifiriuc, Luca Piubello Orsini, Stefano Landi, Chiara Leardini, Massimiliano Perduca, Luca Dalle Carbonare and Maria Teresa Valenti
Microorganisms 2025, 13(8), 1923; https://doi.org/10.3390/microorganisms13081923 - 18 Aug 2025
Abstract
Hospital-acquired infections (HAIs) remain a major clinical and economic burden, with pathogens such as Escherichia coli contributing to high rates of morbidity and mortality. Traditional manual disinfection methods are often insufficient, particularly in high-risk hospital environments. In this study, we investigated innovative strategies [...] Read more.
Hospital-acquired infections (HAIs) remain a major clinical and economic burden, with pathogens such as Escherichia coli contributing to high rates of morbidity and mortality. Traditional manual disinfection methods are often insufficient, particularly in high-risk hospital environments. In this study, we investigated innovative strategies to enhance surface decontamination and reduce infection risk. First, we assessed the efficacy of the SMEG BPW1260 bedpan washer-disinfector, a thermal disinfection system for human waste containers. Our results demonstrated a reduction in Clostridium difficile and Escherichia coli contamination by >99.9% (>3 log reduction), as measured by colony-forming units (CFU) before and after treatment. Molecular techniques, including spectrophotometry, cell counting, and quantitative PCR (qPCR) for DNA quantification, confirmed reduction in bacterial contamination. Specifically, Clostridium difficile showed a reduction of approximately 89% in both optical density (OD) and cell count (cells/mL). In the case of Escherichia coli, a reduction of around 82% in OD was observed, with an even more pronounced decrease in cell count, reaching approximately 99.3%. For both bacteria, DNA quantification by qPCR was below detectable limits. Furthermore, we optimized the energy efficiency of the disinfection cycle, achieving a 45% reduction in power consumption compared to standard protocols without compromising antimicrobial efficacy. Secondly, we developed a sustainable cleaning solution based on methyl ester sulfonate surfactants derived from waste cooking oil. The detergent’s antibacterial activity was tested on contaminated surfaces and further enhanced through the incorporation of nanoassemblies composed of silver, electrostatically bound either to biomimetic magnetic nanoparticles or to conventional magnetic nanoparticles. Washing with the detergent alone effectively eliminated detectable contamination, while the addition of nanoparticles inhibited bacterial regrowth. Antimicrobial testing against E. coli revealed that the nanoparticle-enriched formulations reduced the average MIC values by approximately 50%, with MIC50 values around 0.03–0.06 mg/mL and MIC90 values between 0.06 and 0.12 mg/mL, indicating improved inhibitory efficacy. Finally, recognizing the infection risks associated with intra-hospital transport, we tested the SAFE-HUG Wheelchair Cover, a disposable non-woven barrier designed to reduce patient exposure to contaminated wheelchair surfaces. Use of the cover resulted in a 3.3 log reduction in surface contamination, based on viable cell counts. Optical density and bacterial DNA were undetectable in all covered samples at both 1 and 24 h, confirming the strong barrier effect. Together, these approaches—thermal no-touch disinfection, eco-friendly detergent boosted with nanoparticles, and protective transport barriers—respond to the urgent need for effective, sustainable infection control methods in healthcare settings. Our findings demonstrate the potential of these systems to counteract microbial contamination while minimizing environmental impact, offering promising solutions for the future of infection prevention in healthcare settings. Full article
(This article belongs to the Special Issue Pathogen Infection and Public Health)
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21 pages, 4704 KiB  
Article
Effect of Waste Metal and Chamotte Fillers on the Thermal and Mechanical Properties of Geopolymer Composites for Energy Storage Applications
by Aleš Soukup, Mohammadtaghi Vakili and Pavlína Hájková
Materials 2025, 18(16), 3853; https://doi.org/10.3390/ma18163853 - 17 Aug 2025
Abstract
This study investigates the effects of varying filler content on the thermal and mechanical performance of metakaolinite-based geopolymer composites designed for thermal energy storage applications. The composites were formulated using a geopolymer binder, combined with a thermally stable filler (ground chamotte) and a [...] Read more.
This study investigates the effects of varying filler content on the thermal and mechanical performance of metakaolinite-based geopolymer composites designed for thermal energy storage applications. The composites were formulated using a geopolymer binder, combined with a thermally stable filler (ground chamotte) and a thermal energy storage filler (waste steel chips) in different proportions. Chamotte content within the binder matrix (binder + chamotte) ranged from 20 to 40 wt.%, while steel chip content varied from 0 to 40 wt.% of the total composite mass. The thermal properties of the composites were evaluated at room temperature and compared with conventional reference materials, including Ultraboard, chamotte brick, and magnetite brick. Mechanical performance, specifically flexural and compressive strength, was evaluated at room temperature and after exposure to elevated temperatures (800 and 1100 °C), followed by two cooling regimes, slow furnace cooling and rapid water quenching. Microstructural characterization via optical microscopy was used to examine filler dispersion and matrix–filler interactions. The results showed that the thermal effusivity of the optimized composites exceeded that of chamotte brick by more than 50%. The highest flexural (12.68 MPa) and compressive (86.18 MPa) strengths were achieved in the composite containing 20 wt.% steel chips, prior to thermal exposure. Microstructural observations revealed the diverse geometry of the steel chips and arrangement of the chamotte particles. These findings highlight the potential of incorporating metallic waste materials into geopolymer systems to develop multifunctional composites with improved thermal storage capacity and mechanical resilience. Full article
(This article belongs to the Section Advanced Composites)
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16 pages, 555 KiB  
Article
Low-PAPR ASE-DMT Using Constellation Extension for Optical Wireless Communications
by Yue Wu, Yiding Li and Baolong Li
Sensors 2025, 25(16), 5109; https://doi.org/10.3390/s25165109 - 17 Aug 2025
Abstract
In the realm of optical wireless communication (OWC), augmented spectral efficiency discrete multitone (ASE-DMT) has been widely recognized as a promising modulation due to its outstanding spectral efficiency and high power efficiency. However, ASE-DMT exhibits an inherently high peak-to-average power ratio (PAPR), which [...] Read more.
In the realm of optical wireless communication (OWC), augmented spectral efficiency discrete multitone (ASE-DMT) has been widely recognized as a promising modulation due to its outstanding spectral efficiency and high power efficiency. However, ASE-DMT exhibits an inherently high peak-to-average power ratio (PAPR), which exacerbates error propagation and leads to a substantial transmission performance degradation in the successive interference cancellation (SIC) receiver of ASE-DMT. Therefore, a novel low-PAPR ASE-DMT scheme (LP-ASE-DMT) is proposed in the paper. Given the intricate multi-depth signal superposition of ASE-DMT, a progressive multi-level constellation extension algorithm is developed to effectively suppress the PAPR of the transmitted signal, while simultaneously achieving much lower computational complexity compared to conventional constellation extension schemes. Furthermore, a dedicated receiver architecture is designed for LP-ASE-DMT, in which a low-complexity modulo operation is employed to eliminate the impact of constellation extension without incurring significant additional receiver complexity. The effectiveness of the proposed LP-ASE-DMT scheme is validated through simulation, revealing a substantial mitigation of PAPR compared to its counterparts. This improvement notably strengthens the system’s robustness to nonlinear impairments. Consequently, LP-ASE-DMT enjoys superior performance across multiple metrics, including bit error rate (BER), power efficiency, and spectral efficiency. Full article
(This article belongs to the Section Communications)
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51 pages, 5199 KiB  
Review
Recent Advances in C-Band High-Power and High-Speed Radio Frequency Photodiodes: Review, Theory and Applications
by Saeed Haydhah, Fabien Ferrero, Xiupu Zhang and Ahmed A. Kishk
Photonics 2025, 12(8), 820; https://doi.org/10.3390/photonics12080820 - 17 Aug 2025
Abstract
A review of the recent research work on high-power and high-speed (HPHS) Ge-on-Si photodiode design is presented, using Silicon Photonics (SiPh) technology, suitable for Radio-over-Fiber base station schemes. The Photodiode (PD) principle of operation, its structure for high RF photogenerated power, and the [...] Read more.
A review of the recent research work on high-power and high-speed (HPHS) Ge-on-Si photodiode design is presented, using Silicon Photonics (SiPh) technology, suitable for Radio-over-Fiber base station schemes. The Photodiode (PD) principle of operation, its structure for high RF photogenerated power, and the achieved PD wide bandwidth are presented. Then, the PD equivalent circuit models are introduced to obtain the PD S-parameters and operating bandwidth, such that efficient power coupling to mmWave loads is realized. Then, the PD theoretical transit-time and RC-time bandwidths are presented, and the PD photocurrent behavior against input optical power, and the optical signal manipulation techniques to improve the PD performance are also presented. After that, the impedance matching techniques between the PD output impedance and antenna input impedance are presented. Finally, recent photonic mmWave antenna designs are introduced. Full article
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30 pages, 83993 KiB  
Article
Region Segmentation for Efficient Semiconductor Inspection: A Deep Learning Approach with Transformers and Atrous Convolution
by Herman Koara, Hai Gong, Chao Xu, Shengze Cai and Xu Zhou
Electronics 2025, 14(16), 3260; https://doi.org/10.3390/electronics14163260 - 17 Aug 2025
Abstract
This paper explores the application of deep learning to automate the traditionally manual creation of inspection recipes for machine vision scenarios requiring complex region selection, such as those found in semiconductor manufacturing. Manually selecting and cropping functional regions in ultra-high-resolution images for analysis [...] Read more.
This paper explores the application of deep learning to automate the traditionally manual creation of inspection recipes for machine vision scenarios requiring complex region selection, such as those found in semiconductor manufacturing. Manually selecting and cropping functional regions in ultra-high-resolution images for analysis and inspection can take anywhere from tens of minutes to hours. To address this challenge, we propose a model whose encoder integrates atrous convolution into a transformer architecture for better feature extraction. This approach is designed to improve segmentation accuracy while maintaining efficiency in processing large-scale semiconductor images. By automating the selection and cropping process, the proposed method aims to streamline quality inspection workflows, reduce manual labor, and accelerate automated optical inspection. Experimental results demonstrate that the model achieves high segmentation performance, with segmentation accuracy reaching 98% and a faster model inference, making it a practical and effective solution for enabling large-scale automation in semiconductor inspection. This research highlights the potential of deep learning-based methods to transform inspection processes, ensuring higher efficiency and product quality across semiconductor manufacturing industries. Full article
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21 pages, 2711 KiB  
Article
Development of a Polyclonal Antibody for the Immunoanalysis of Ochratoxin A (OTA) by Employing a Specially Designed Synthetic OTA Derivative as the Immunizing Hapten
by Chrysoula-Evangelia Karachaliou, Christos Zikos, Christos Liolios, Maria Pelecanou and Evangelia Livaniou
Toxins 2025, 17(8), 415; https://doi.org/10.3390/toxins17080415 - 16 Aug 2025
Abstract
We report herein the development of a polyclonal antibody against ochratoxin A (OTA) using a specially designed synthetic OTA derivative as the immunizing hapten. This OTA derivative contains a tetrapeptide linker (glycyl-glycyl-glycyl-lysine, GGGK), through which it can be linked to a carrier protein [...] Read more.
We report herein the development of a polyclonal antibody against ochratoxin A (OTA) using a specially designed synthetic OTA derivative as the immunizing hapten. This OTA derivative contains a tetrapeptide linker (glycyl-glycyl-glycyl-lysine, GGGK), through which it can be linked to a carrier protein and form an immunogenic conjugate. The OTA derivative (OTA-glycyl-glycyl-glycyl-lysine, OTA-GGGK) has been synthesized on a commercially available resin via the well-established Fmoc-based solid-phase peptide synthesis (Fmoc-SPPS) strategy; overall, this approach has allowed us to avoid tedious liquid-phase synthesis protocols, which are often characterized by multiple steps, several intermediate products and low overall yield. Subsequently, OTA-GGGK was conjugated to bovine thyroglobulin through glutaraldehyde, and the conjugate was used in an immunization protocol. The antiserum obtained was evaluated with a simple-format ELISA in terms of its titer and capability of recognizing the natural free hapten; the anti-OTA antibody, as a whole IgG fragment, was successfully applied to three different immunoanalytical systems for determining OTA in various food materials and wine samples, i.e., a multi-mycotoxin microarray bio-platform, an optical immunosensor, and a biotin–streptavidin ELISA, which has proved the analytical effectiveness and versatility of the anti-OTA antibody developed. The same approach may be followed for developing antibodies against other low-molecular-weight toxins and hazardous substances. Full article
(This article belongs to the Section Mycotoxins)
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16 pages, 4026 KiB  
Article
Design and Optimization Analysis of a Multipoint Flexible Adhesive Support Structure for a Spaceborne Rectangular Curved Prism
by Xinyin Jia, Bingliang Hu, Xianqiang He, Siyuan Li and Jia Liu
Appl. Sci. 2025, 15(16), 9050; https://doi.org/10.3390/app15169050 - 16 Aug 2025
Viewed by 112
Abstract
Curved prisms can serve as core components of dispersive spectroscopy and converge light paths, making them widely used in spectral imaging technology. Their positional stability, surface shape errors, and temperature stability in optical systems directly affect the performance of spectral imaging systems. On [...] Read more.
Curved prisms can serve as core components of dispersive spectroscopy and converge light paths, making them widely used in spectral imaging technology. Their positional stability, surface shape errors, and temperature stability in optical systems directly affect the performance of spectral imaging systems. On the basis of the analysis of design indicators and optimization of the support structure for curved prisms, a multipoint flexible adhesive support structure (MPPASS) of large rectangular curved prisms for space-based application is proposed. The novelty of the MPPASS lies in its ability to achieve micro-stress and high stability support for large-aperture rectangular optical elements through the bonding of peripheral small points and the introduction of flexible bonding rings. The design principles of the adhesive support structure were deeply studied, and on this basis, the engineering design, finite element analysis, adhesive testing, and mechanical testing of large curved prisms were completed. The designed curved prism assembly has a maximum deformation displacement of 0.0085 mm and a maximum tilt angle of 0.65” under gravity loading, a first-order frequency of 1003.5 Hz, and a maximum acceleration amplification factor of 3.12 in the X, Y, and Z directions. The root mean square (RMS) variation value of the mirror shape errors for the curved prism assembly was 5.26 nm under a uniform temperature load of 20 ± 1 °C, and the RMS value of the mirror shape errors was 0.019 λ after mechanical testing. The installation surface flatness of 0.02 mm did not significantly affect its mirror shape errors. The experimental results verified the rationality of the design, temperature stability, and mechanical stability of the MPPASS. Full article
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14 pages, 2419 KiB  
Article
Combined Lithium-Rich Czochralski Growth and Diffusion Method for Z-Cut Near-Stoichiometric Lithium Niobate Crystals and the Study of Periodic Domain Structures
by Xuefeng Xiao, Yan Zhang, Han Zhang, Jiayi Chen, Yan Huang, Jiashun Si, Shuaijie Liang, Qingyan Xu, Huan Zhang, Lingling Ma, Cui Yang and Xuefeng Zhang
Crystals 2025, 15(8), 727; https://doi.org/10.3390/cryst15080727 - 16 Aug 2025
Viewed by 56
Abstract
This paper presents the preparation of Z-cut near-stoichiometric lithium niobate (NSLN) wafers using a combined process of the lithium-rich Czochralski growth and diffusion methods. The fabricated Z-cut NSLN wafers exhibited outstanding comprehensive performance, including a high Curie temperature of up to 1200 °C, [...] Read more.
This paper presents the preparation of Z-cut near-stoichiometric lithium niobate (NSLN) wafers using a combined process of the lithium-rich Czochralski growth and diffusion methods. The fabricated Z-cut NSLN wafers exhibited outstanding comprehensive performance, including a high Curie temperature of up to 1200 °C, a refractive index gradient in the diameter direction below 1.5 × 10−4 cm−1, and a UV absorption edge shifted 14 nm toward the ultraviolet region compared to congruent lithium niobate crystals, with a coercive field of 1268 V/mm. Additionally, the wafers demonstrated excellent processing characteristics, with the bow of 4-inch wafers controlled within 55 μm, surpassing the machining standards of traditional lithium niobate wafers of the same size. These results indicated the highly uniform chemical stoichiometry and crystallization quality of the wafers. Leveraging the high uniformity and low coercive field of the wafers, periodic triangular domain structure arrays were successfully fabricated, laying the foundation for domain engineering design in electro-optic deflectors and switching devices. This study not only achieves the scalable preparation of NSLN wafers but also provides a reliable technical solution for their practical applications in high-performance electro-optic devices. Full article
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177 pages, 57849 KiB  
Systematic Review
Sensor Arrays: A Comprehensive Systematic Review
by Sergio Domínguez-Gimeno, Raúl Igual-Catalán and Inmaculada Plaza-García
Sensors 2025, 25(16), 5089; https://doi.org/10.3390/s25165089 - 15 Aug 2025
Viewed by 119
Abstract
Sensor arrays are arrangements of sensors that follow a certain pattern, usually in a row–column distribution. This study presents a systematic review on sensor arrays. For this purpose, several systematic searches of recent studies covering a period of 10 years were performed. As [...] Read more.
Sensor arrays are arrangements of sensors that follow a certain pattern, usually in a row–column distribution. This study presents a systematic review on sensor arrays. For this purpose, several systematic searches of recent studies covering a period of 10 years were performed. As a result of these searches, 361 papers have been analyzed in detail. The most relevant aspects for sensor array design have been studied. In relation to sensing technologies, different categories were identified: resistive/piezoresistive, capacitive, inductive, diode-based, transistor-based, triboelectric, fiber optic, Hall effect-based, piezoelectric, and bioimpedance-based. Other aspects of sensor array design have also been analyzed: applications, validation experiments, software used for sensor array data analysis, sensor array characteristics, and performance metrics. For each aspect, the studies were classified into different subcategories. As a result of this analysis, different emerging technologies and future research challenges in sensor arrays were identified. Full article
(This article belongs to the Section Electronic Sensors)
19 pages, 2963 KiB  
Article
Theoretical Design of Composite Stratified Nanohole Arrays for High-Figure-of-Merit Plasmonic Hydrogen Sensors
by Jiyu Feng, Yuting Liu, Xinyi Chen, Mingyu Cheng and Bin Ai
Chemosensors 2025, 13(8), 309; https://doi.org/10.3390/chemosensors13080309 - 15 Aug 2025
Viewed by 103
Abstract
Fast, spark-free detection of hydrogen leaks is indispensable for large-scale hydrogen deployment, yet electronic sensors remain power-intensive and prone to cross-talk. Optical schemes based on surface plasmons enable remote read-out, but single-metal devices offer either weak H2 affinity or poor plasmonic quality. Here [...] Read more.
Fast, spark-free detection of hydrogen leaks is indispensable for large-scale hydrogen deployment, yet electronic sensors remain power-intensive and prone to cross-talk. Optical schemes based on surface plasmons enable remote read-out, but single-metal devices offer either weak H2 affinity or poor plasmonic quality. Here we employ full-wave finite-difference time-domain (FDTD) simulations to map the hydrogen response of nanohole arrays (NAs) that can be mass-produced by colloidal lithography. Square lattices of 200 nm holes etched into 100 nm films of Pd, Mg, Ti, V, or Zr expose an intrinsic trade-off: Pd maintains sharp extraordinary optical transmission modes but shifts by only 28 nm upon hydriding, whereas Mg undergoes a large dielectric transition that extinguishes its resonance. Vertical pairing of a hydride-forming layer with a noble metal plasmonic cap overcomes this limitation. A Mg/Pd bilayer preserves all modes and red-shifts by 94 nm, while the predicted optimum Ag (60 nm)/Mg (40 nm) stack delivers a 163 nm shift with an 83 nm linewidth, yielding a figure of merit of 1.96—surpassing the best plasmonic hydrogen sensors reported to date. Continuous-film geometry suppresses mechanical degradation, and the design rules—noble-metal plasmon generator, buried hydride layer, and thickness tuning—are general. This study charts a scalable route to remote, sub-ppm, optical hydrogen sensors compatible with a carbon-neutral energy infrastructure. Full article
(This article belongs to the Special Issue Innovative Gas Sensors: Development and Application)
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44 pages, 6372 KiB  
Review
Metal–Organic-Framework-Based Optical Biosensors: Recent Advances in Pathogen Detection and Environmental Monitoring
by Alemayehu Kidanemariam and Sungbo Cho
Sensors 2025, 25(16), 5081; https://doi.org/10.3390/s25165081 - 15 Aug 2025
Viewed by 106
Abstract
Metal–organic frameworks (MOFs) have emerged as highly versatile materials for the development of next-generation optical biosensors owing to their tunable porosity, large surface area, and customizable chemical functionality. Recently, MOF-based platforms have shown substantial potential in various optical transduction modalities, including fluorescence, luminescence, [...] Read more.
Metal–organic frameworks (MOFs) have emerged as highly versatile materials for the development of next-generation optical biosensors owing to their tunable porosity, large surface area, and customizable chemical functionality. Recently, MOF-based platforms have shown substantial potential in various optical transduction modalities, including fluorescence, luminescence, and colorimetric sensing, enabling the highly sensitive and selective detection of biological analytes. This review provides a comprehensive overview of recent advancements in MOF-based optical biosensors, focusing on their applications in pathogen detection and environmental monitoring. We highlight key design strategies, including MOF functionalization, hybridization with nanoparticles or dyes, and integration into microfluidic and wearable devices. Emerging methods, such as point-of-care diagnostics, label-free detection, and real-time monitoring, are also discussed. Finally, the current challenges and future directions for the practical deployment of MOF-based optical biosensors in clinical and field environments are discussed. Full article
(This article belongs to the Special Issue Feature Review Papers in Biosensors Section 2025)
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13 pages, 5414 KiB  
Article
Modelling of Tiled Grating Arrangement Efficiency
by Haritha Vijayakumar Sheela, Gabor Horváth and Miklós Füle
Photonics 2025, 12(8), 818; https://doi.org/10.3390/photonics12080818 - 15 Aug 2025
Viewed by 120
Abstract
The precise alignment of individual diffraction grating units within a tiled grating assembly (TGA) is essential for enhancing the quality of optical throughput and overall functional performance of such kinds of optical systems. This study presents a comprehensive simulation analysis of TGAs comprising [...] Read more.
The precise alignment of individual diffraction grating units within a tiled grating assembly (TGA) is essential for enhancing the quality of optical throughput and overall functional performance of such kinds of optical systems. This study presents a comprehensive simulation analysis of TGAs comprising two and four gratings to assess the sensitivity of optical imaging performance to a range of induced alignment errors. The misalignments are systematically introduced to the grating sections in the tiled grating assemblies, and their effects in far-field imaging are examined and compared. The results highlight the critical role of accurate alignment in maintaining coherent beam combination and optimal system performance. Zemax OpticStudio®-based simulations offer valuable insights for designing high-performance, large-aperture grating systems and pave the way for future experimental validation and integration. Full article
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33 pages, 6610 KiB  
Article
Characterization of the Physical, Mechanical, and Thermal Properties of Cement and Compressed Earth Stabilized Blocks, Incorporating Closed-Loop Materials for Use in Hot and Humid Climates
by Catalina Reyna-Ruiz, José Manuel Gómez-Soberón and María Neftalí Rojas-Valencia
Buildings 2025, 15(16), 2891; https://doi.org/10.3390/buildings15162891 - 15 Aug 2025
Viewed by 176
Abstract
The United States of America could build 20,000 bases for the Statue of Liberty every year using its construction and demolition waste, and 456 bases using waste glass from jars and bottles. However, some sectors of the population still face a shortage of [...] Read more.
The United States of America could build 20,000 bases for the Statue of Liberty every year using its construction and demolition waste, and 456 bases using waste glass from jars and bottles. However, some sectors of the population still face a shortage of affordable housing. The challenges of disposing of such large amounts of waste and solving the housing shortage could be addressed together if these materials, considered part of a closed-loop system, were integrated into new building blocks. This research studies compressed earth blocks that incorporate soils and gravels excavated in situ, river sand, crushed concrete from demolition waste, and recycled glass sand. To stabilize the blocks, cement is used at 5, 10, and 15% (by weight). The properties studied include the following: density, apparent porosity, initial water absorption, simple compression, modulus of elasticity, and thermal conductivity. Optical image analysis proved to be a tool for predicting the values of these properties as the stabilizer changed. To assist in decision making regarding the best overall performance of the total 12 mix designs, a ranking system is proposed. The best blocks, which incorporate the otherwise waste materials, exhibited simple compression values up to 7.3 MPa, initial water absorption of 8 g/(cm2 × min0.5) and thermal conductivity of 0.684 W/m·K. Full article
(This article belongs to the Section Building Materials, and Repair & Renovation)
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