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Search Results (3,143)

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Keywords = chemical identification

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21 pages, 19752 KiB  
Article
Phase Characterisation for Recycling of Shredded Waste Printed Circuit Boards
by Laurance Donnelly, Duncan Pirrie, Matthew Power and Andrew Menzies
Recycling 2025, 10(4), 157; https://doi.org/10.3390/recycling10040157 - 6 Aug 2025
Abstract
In this study, we adopt a geometallurgical analytical approach common in mineral processing in the characterization of samples of shredded waste printed circuit board (PCB) E-waste, originating from Europe. Conventionally, bulk chemical analysis provides a value for E-waste; however, chemical analysis alone does [...] Read more.
In this study, we adopt a geometallurgical analytical approach common in mineral processing in the characterization of samples of shredded waste printed circuit board (PCB) E-waste, originating from Europe. Conventionally, bulk chemical analysis provides a value for E-waste; however, chemical analysis alone does not provide information on the textural variability, phase complexity, grain size, particle morphology, phase liberation and associations. To address this, we have integrated analysis using binocular microscopy, manual scanning electron microscopy, phase, textural and compositional analyses by automated (SEM-EDS), phase analysis based on (Automated Material Identification and Classification System (AMICS) software, and elemental analysis using micro-XRF. All methods used have strengths and limitations, but an integration of these analytical tools allows the detailed characterization of the texture and composition of the E-waste feeds, ahead of waste reprocessing. These data can then be used to aid the design of optimized processing circuits for the recovery of the key payable components, and assist in the commercial trading of e-scrap. Full article
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23 pages, 4361 KiB  
Article
Novel Visible Light-Driven Ho2InSbO7/Ag3PO4 Photocatalyst for Efficient Oxytetracycline Contaminant Degradation
by Jingfei Luan and Tiannan Zhao
Molecules 2025, 30(15), 3289; https://doi.org/10.3390/molecules30153289 - 6 Aug 2025
Abstract
In this study, a Z-scheme Ho2InSbO7/Ag3PO4 (HAO) heterojunction photocatalyst was successfully fabricated for the first time by ultrasound-assisted solvothermal method. The structural features, compositional components and morphological characteristics of the synthesized materials were thoroughly characterized by [...] Read more.
In this study, a Z-scheme Ho2InSbO7/Ag3PO4 (HAO) heterojunction photocatalyst was successfully fabricated for the first time by ultrasound-assisted solvothermal method. The structural features, compositional components and morphological characteristics of the synthesized materials were thoroughly characterized by a series of techniques, including X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectrum, X-ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. A comprehensive array of analytical techniques, including ultraviolet-visible diffuse reflectance absorption spectra, photoluminescence spectroscopy, time-resolved photoluminescence spectroscopy, photocurrent testing, electrochemical impedance spectroscopy, electron paramagnetic resonance, and ultraviolet photoelectron spectroscopy, was employed to systematically investigate the optical, chemical, and photoelectronic properties of the materials. Using oxytetracycline (OTC), a representative tetracycline antibiotic, as the target substrate, the photocatalytic activity of the HAO composite was assessed under visible light irradiation. Comparative analyses demonstrated that the photocatalytic degradation capability of the HAO composite surpassed those of its individual components. Notably, during the degradation process, the application of the HAO composite resulted in an impressive removal efficiency of 99.89% for OTC within a span of 95 min, along with a total organic carbon mineralization rate of 98.35%. This outstanding photocatalytic performance could be ascribed to the efficient Z-scheme electron-hole separation system occurring between Ho2InSbO7 and Ag3PO4. Moreover, the adaptability and stability of the HAO heterojunction were thoroughly validated. Through experiments involving the capture of reactive species and electron paramagnetic resonance analysis, the active species generated by HAO were identified as hydroxyl radicals (•OH), superoxide anions (•O2), and holes (h+). This identification provides valuable insights into the mechanisms and pathways associated with the photodegradation of OTC. In conclusion, this research not only elucidates the potential of HAO as an efficient Z-scheme heterojunction photocatalyst but also marks a significant contribution to the advancement of sustainable remediation strategies for OTC contamination. Full article
(This article belongs to the Special Issue Nanomaterials in Photochemical Devices: Advances and Applications)
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20 pages, 1523 KiB  
Article
Structural and Vibrational Characterizations of Alizarin Red S
by César A. N. Catalán, Licínia L. G. Justino, Rui Fausto, Gulce O. Ildiz and Silvia Antonia Brandán
Molecules 2025, 30(15), 3286; https://doi.org/10.3390/molecules30153286 - 5 Aug 2025
Abstract
In this work, the structures of the isolated anion and anhydrous and monohydrated sodium salts of alizarin red S (ARS) have been theoretically investigated within the density functional theory framework (B3LYP/6-311++G** calculations). The combination of calculations with the scaled quantum mechanics force field [...] Read more.
In this work, the structures of the isolated anion and anhydrous and monohydrated sodium salts of alizarin red S (ARS) have been theoretically investigated within the density functional theory framework (B3LYP/6-311++G** calculations). The combination of calculations with the scaled quantum mechanics force field (SQMFF) methodology has allowed the assignment of the experimental infrared spectrum of ARS in the solid phase and the determination of the corresponding force constants. The structural analysis also included the investigation of the NMR and UV-visible spectra of the compound in solution in light of the undertaken quantum chemical calculations, the obtained theoretical data being in good agreement with the corresponding experimental ones. The impact of the presence of the Na+ counterion and hydration water on the properties of the organic ARS fragment was evaluated. Atoms in molecules theory (AIM) analysis was also undertaken to obtain further details on the electronic structure of the investigated species, and the HOMO-LUMO gap was determined to evaluate their relative reactivity. Globally, the results obtained in this work extend the available information on alizarin red S and may also be used for the fast identification of the three studied species of the compound investigated (anhydrous and monohydrated sodium salts and isolated anion). Full article
(This article belongs to the Section Molecular Structure)
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15 pages, 5625 KiB  
Article
Effect of Phosphogypsum Characteristics on the Properties of Phosphogypsum-Based Binders
by Nataliya Alfimova, Kseniya Levickaya, Il’ya Buhtiyarov, Ivan Nikulin, Marina Kozhukhova and Valeria Strokova
J. Compos. Sci. 2025, 9(8), 413; https://doi.org/10.3390/jcs9080413 - 4 Aug 2025
Viewed by 193
Abstract
Phosphogypsum, a byproduct of orthophosphoric acid production, is one of the large-tonnage wastes. Since phosphogypsum mainly consists of CaSO4 2H2O, it can be considered as an alternative gypsum-bearing raw material in the production of gypsum binders. However, its features, such [...] Read more.
Phosphogypsum, a byproduct of orthophosphoric acid production, is one of the large-tonnage wastes. Since phosphogypsum mainly consists of CaSO4 2H2O, it can be considered as an alternative gypsum-bearing raw material in the production of gypsum binders. However, its features, such as particle morphology and the presence of impurities, can negatively affect the characteristics of phosphogypsum-based binders. Identification of these factors will allow us to develop methods for their minimization and increasing the efficiency of phosphogypsum use from the required source as a raw material for the production of phosphogypsum-based binders. In this regard, the manuscript contains a comprehensive and comparative analysis of phosphogypsum and natural gypsum, which makes it possible to establish their differences in chemical composition and structural and morphological features, which subsequently affect the properties of the phosphogypsum-based binder. It has been established that the key factor negatively affecting the strength of phosphogypsum-based paste (2.58 MPa) is its high water demand (0.89), which is due to the high values of the specific surface area of the particles and the presence of a large number of conglomerates with significant porosity in phosphogypsum. It has been suggested that preliminary grinding of phosphogypsum can help reduce the amount of water required to obtain fresh phosphogypsum-based paste with a standard consistency and improve its physical and mechanical properties. Full article
(This article belongs to the Special Issue From Waste to Advance Composite Materials, 2nd Edition)
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15 pages, 1832 KiB  
Article
PyBEP: An Open-Source Tool for Electrode Potential Determination from Battery OCV Measurements
by Jon Pišek, Tomaž Katrašnik and Klemen Zelič
Batteries 2025, 11(8), 295; https://doi.org/10.3390/batteries11080295 - 4 Aug 2025
Viewed by 173
Abstract
This paper introduces PyBEP, a Python-based tool for the automated and optimized selection of open-circuit potential (OCP) curves and calculation of stoichiometric cycling ranges for lithium-ion battery electrodes based on open-circuit voltage (OCV) measurements. Thereby, it overcomes key challenges in traditional approaches, which [...] Read more.
This paper introduces PyBEP, a Python-based tool for the automated and optimized selection of open-circuit potential (OCP) curves and calculation of stoichiometric cycling ranges for lithium-ion battery electrodes based on open-circuit voltage (OCV) measurements. Thereby, it overcomes key challenges in traditional approaches, which are often time-intensive and susceptible to errors due to manual curve digitization, data inconsistency, and coding complexities. The originality of PyBEP arises from the systematic integration of automated electrode chemistry identification, quality-controlled database usage, refinement of the results using incremental capacity methodology, and simultaneous optimization of multiple electrode parameters. The PyBEP database leverages high-quality, curated OCP data and employs differential evolution optimization for precise OCP determination. Validation against literature data and experimental results confirms the robustness and accuracy of PyBEP, consistently achieving precision of 10 mV or better. PyBEP also offers features like electrode chemical composition identification and quality enhancement of measurement data, further extending the battery modeling functionalities without the need for battery disassembly. PyBEP is open-source and accessible on GitHub, providing a streamlined, accurate resource for the battery research community, making PyBEP a unique and directly applicable toolkit for electrochemical researchers and engineers. Full article
(This article belongs to the Section Battery Modelling, Simulation, Management and Application)
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18 pages, 10604 KiB  
Article
Fast Detection of Plants in Soybean Fields Using UAVs, YOLOv8x Framework, and Image Segmentation
by Ravil I. Mukhamediev, Valentin Smurygin, Adilkhan Symagulov, Yan Kuchin, Yelena Popova, Farida Abdoldina, Laila Tabynbayeva, Viktors Gopejenko and Alexey Oxenenko
Drones 2025, 9(8), 547; https://doi.org/10.3390/drones9080547 - 1 Aug 2025
Viewed by 223
Abstract
The accuracy of classification and localization of plants on images obtained from the board of an unmanned aerial vehicle (UAV) is of great importance when implementing precision farming technologies. It allows for the effective application of variable rate technologies, which not only saves [...] Read more.
The accuracy of classification and localization of plants on images obtained from the board of an unmanned aerial vehicle (UAV) is of great importance when implementing precision farming technologies. It allows for the effective application of variable rate technologies, which not only saves chemicals but also reduces the environmental load on cultivated fields. Machine learning algorithms are widely used for plant classification. Research on the application of the YOLO algorithm is conducted for simultaneous identification, localization, and classification of plants. However, the quality of the algorithm significantly depends on the training set. The aim of this study is not only the detection of a cultivated plant (soybean) but also weeds growing in the field. The dataset developed in the course of the research allows for solving this issue by detecting not only soybean but also seven weed species common in the fields of Kazakhstan. The article describes an approach to the preparation of a training set of images for soybean fields using preliminary thresholding and bound box (Bbox) segmentation of marked images, which allows for improving the quality of plant classification and localization. The conducted research and computational experiments determined that Bbox segmentation shows the best results. The quality of classification and localization with the application of Bbox segmentation significantly increased (f1 score increased from 0.64 to 0.959, mAP50 from 0.72 to 0.979); for a cultivated plant (soybean), the best classification results known to date were achieved with the application of YOLOv8x on images obtained from the UAV, with an f1 score = 0.984. At the same time, the plant detection rate increased by 13 times compared to the model proposed earlier in the literature. Full article
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14 pages, 1632 KiB  
Article
Try It Before You Buy It: A Non-Invasive Authenticity Assessment of a Purported Phoenician Head-Shaped Pendant (Cáceres, Spain)
by Valentina Lončarić, Pedro Barrulas, José Miguel González Bornay and Mafalda Costa
Heritage 2025, 8(8), 308; https://doi.org/10.3390/heritage8080308 - 1 Aug 2025
Viewed by 147
Abstract
Museums may acquire archaeological artefacts discovered by non-specialists or amateur archaeologists, holding the potential to promote the safeguarding of cultural heritage by integrating the local community in their activities. However, this also creates an opportunity for the fraudulent sale of modern forgeries presented [...] Read more.
Museums may acquire archaeological artefacts discovered by non-specialists or amateur archaeologists, holding the potential to promote the safeguarding of cultural heritage by integrating the local community in their activities. However, this also creates an opportunity for the fraudulent sale of modern forgeries presented as archaeological artefacts, resulting in the need for a critical assessment of the artefact’s authenticity prior to acquisition by the museum. In 2019, the regional museum in Cáceres (Spain) was offered the opportunity to acquire a Phoenician-Punic head pendant, allegedly discovered in the vicinity of the city. The artefact’s authenticity was assessed by traditional approaches, including typological analysis and analysis of manufacture technique, which raised doubts about its purported age. VP-SEM-EDS analysis of the chemical composition of the different glass portions comprising the pendant was used for non-invasive determination of glassmaking recipes, enabling the identification of glass components incompatible with known Iron Age glassmaking recipes from the Mediterranean. Further comparison with historical and modern glassmaking recipes allowed for the identification of the artefact as a recent forgery made from glasses employing modern colouring and opacifying techniques. Full article
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36 pages, 3621 KiB  
Review
Harnessing Molecular Phylogeny and Chemometrics for Taxonomic Validation of Korean Aromatic Plants: Integrating Genomics with Practical Applications
by Adnan Amin and Seonjoo Park
Plants 2025, 14(15), 2364; https://doi.org/10.3390/plants14152364 - 1 Aug 2025
Viewed by 365
Abstract
Plant genetics and chemotaxonomic analysis are considered key parameters in understanding evolution, plant diversity and adaptation. Korean Peninsula has a unique biogeographical landscape that supports various aromatic plant species, each with considerable ecological, ethnobotanical, and pharmacological significance. This review aims to provide a [...] Read more.
Plant genetics and chemotaxonomic analysis are considered key parameters in understanding evolution, plant diversity and adaptation. Korean Peninsula has a unique biogeographical landscape that supports various aromatic plant species, each with considerable ecological, ethnobotanical, and pharmacological significance. This review aims to provide a comprehensive overview of the chemotaxonomic traits, biological activities, phylogenetic relationships and potential applications of Korean aromatic plants, highlighting their significance in more accurate identification. Chemotaxonomic investigations employing techniques such as gas chromatography mass spectrometry, high-performance liquid chromatography, and nuclear magnetic resonance spectroscopy have enabled the identification of essential oils and specialized metabolites that serve as valuable taxonomic and diagnostic markers. These chemical traits play essential roles in species delimitation and in clarifying interspecific variation. The biological activities of selected taxa are reviewed, with emphasis on antimicrobial, antioxidant, anti-inflammatory, and cytotoxic effects, supported by bioassay-guided fractionation and compound isolation. In parallel, recent advances in phylogenetic reconstruction employing DNA barcoding, internal transcribed spacer regions, and chloroplast genes such as rbcL and matK are examined for their role in clarifying taxonomic uncertainties and inferring evolutionary lineages. Overall, the search period was from year 2001 to 2025 and total of 268 records were included in the study. By integrating phytochemical profiling, pharmacological evidence, and molecular systematics, this review highlights the multifaceted significance of Korean endemic aromatic plants. The conclusion highlights the importance of multidisciplinary approaches including metabolomics and phylogenomics in advancing our understanding of species diversity, evolutionary adaptation, and potential applications. Future research directions are proposed to support conservation efforts. Full article
(This article belongs to the Special Issue Applications of Bioinformatics in Plant Science)
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10 pages, 726 KiB  
Article
Discovery of New Everninomicin Analogs from a Marine-Derived Micromonospora sp. by Metabolomics and Genomics Approaches
by Tae Hyun Lee, Nathan J. Brittin, Imraan Alas, Christopher D. Roberts, Shaurya Chanana, Doug R. Braun, Spencer S. Ericksen, Song Guo, Scott R. Rajski and Tim S. Bugni
Mar. Drugs 2025, 23(8), 316; https://doi.org/10.3390/md23080316 - 31 Jul 2025
Viewed by 230
Abstract
During the course of genome mining initiatives, we identified a marine-derived Micromonospora, assigned here as strain WMMD956; the genome of WMMD956 appeared to contain a number of features associated with everninomicins, well-known antimicrobial orthosomycins. In addition, LCMS-based hierarchical clustering analysis and principal [...] Read more.
During the course of genome mining initiatives, we identified a marine-derived Micromonospora, assigned here as strain WMMD956; the genome of WMMD956 appeared to contain a number of features associated with everninomicins, well-known antimicrobial orthosomycins. In addition, LCMS-based hierarchical clustering analysis and principal component analysis (hcapca) revealed that WMMD956 displayed an extreme degree of metabolomic and genomic novelty. Dereplication of high-resolution tandem mass spectrometry (HRMS/MS) and Global Natural Product Social molecular networking platform (GNPS) analysis of WMMD956 resulted in the identification of several analogs of the previously known everninomicin. Chemical structures were unambiguously confirmed by HR-ESI-MS, 1D and 2D NMR experiments, and the use of MS/MS data. The isolated metabolites, 13, were evaluated for their antibacterial activity against methicillin-resistant Staphalococcus aureus (MRSA). Full article
(This article belongs to the Special Issue Bioactive Compounds from Extreme Marine Ecosystems)
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19 pages, 3509 KiB  
Article
Explainable Machine Learning Model for Source Type Identification of Mine Inrush Water
by Yong Yang, Jing Li, Huawei Tao, Yong Cheng and Li Zhao
Information 2025, 16(8), 648; https://doi.org/10.3390/info16080648 - 30 Jul 2025
Viewed by 212
Abstract
The prevention and control of mine inrush water has always been a major challenge for safety. By identifying the type of water source and analyzing the real-time changes in water composition, sudden water inrush accidents can be monitored in a timely manner to [...] Read more.
The prevention and control of mine inrush water has always been a major challenge for safety. By identifying the type of water source and analyzing the real-time changes in water composition, sudden water inrush accidents can be monitored in a timely manner to avoid major accidents. This paper proposes a novel explainable machine learning model for source type identification of mine inrush water. The paper expands the original monitoring system into the XinJi No.2 Mine in Huainan Mining Area. Based on the online water composition data, using the Spearman coefficient formula, it analyzes the water chemical characteristics of different aquifers to extract key discriminant factors. Then, the Conv1D-GRU model was built to deeply connect factors for precise water source identification. The experimental results show an accuracy rate of 85.37%. In addition, focused on the interpretability, the experiment quantified the impact of different features on the model using SHAP (Shapley Additive Explanations). It provides new reference for the source type identification of mine inrush water in mine disaster prevention and control. Full article
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28 pages, 1387 KiB  
Article
Metagenomic Analysis of Ready-to-Eat Foods on Retail Sale in the UK Identifies Diverse Genes Related to Antimicrobial Resistance
by Edward Haynes, Roy Macarthur, Marc Kennedy, Chris Conyers, Hollie Pufal, Sam McGreig and John Walshaw
Microorganisms 2025, 13(8), 1766; https://doi.org/10.3390/microorganisms13081766 - 29 Jul 2025
Viewed by 162
Abstract
Antimicrobial Resistance (AMR), i.e., the evolution of microbes to become resistant to chemicals used to control them, is a global public health concern that can make bacterial diseases untreatable. Inputs including antibiotics, metals, and biocides can create an environment in the agrifood chain [...] Read more.
Antimicrobial Resistance (AMR), i.e., the evolution of microbes to become resistant to chemicals used to control them, is a global public health concern that can make bacterial diseases untreatable. Inputs including antibiotics, metals, and biocides can create an environment in the agrifood chain that selects for AMR. Consumption of food represents a potential exposure route to AMR microbes and AMR genes (ARGs), which may be present in viable bacteria or on free DNA. Ready-to-eat (RTE) foods are of particular interest because they are eaten without further cooking, so AMR bacteria or ARGs that are present may be consumed intact. They also represent varied production systems (fresh produce, cooked meat, dairy, etc.). An evidence gap exists regarding the diversity and consumption of ARGs in RTE food, which this study begins to address. We sampled 1001 RTE products at retail sale in the UK, in proportion to their consumption by the UK population, using National Diet and Nutrition Survey data. Bacterial DNA content of sample extracts was assessed by 16S metabarcoding, and 256 samples were selected for metagenomic sequencing for identification of ARGs based on consumption and likely bacterial DNA content. A total of 477 unique ARGs were identified in the samples, including ARGs that may be involved in resistance to important antibiotics, such as colistin, fluoroquinolones, and carbapenems, although phenotypic AMR was not measured. Based on the incidence of ARGs in food types, ARGs are estimated to be present in a high proportion of average diets. ARGs were detected on almost all RTE food types tested (48 of 52), and some efflux pump genes are consumed in 97% of UK diets. Full article
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18 pages, 2151 KiB  
Article
Polyphenol Profile and Biological Activity of the Extracts from Sideritis scardica Griseb. (Lamiaceae) Herb
by Magdalena Walasek-Janusz, Krzysztof Kamil Wojtanowski, Rafał Papliński, Agnieszka Grzegorczyk and Renata Nurzyńska-Wierdak
Pharmaceuticals 2025, 18(8), 1121; https://doi.org/10.3390/ph18081121 - 27 Jul 2025
Viewed by 255
Abstract
Background/Objectives: The beneficial and multifaceted effects of Sideritis scardica Griseb. extracts are attributed to the presence of polyphenolic compounds, particularly phenolic acids. Methods: The research was carried out for S. scardica herb of different origins (Albania, Bulgaria, North Macedonia, and Türkiye). Identification of [...] Read more.
Background/Objectives: The beneficial and multifaceted effects of Sideritis scardica Griseb. extracts are attributed to the presence of polyphenolic compounds, particularly phenolic acids. Methods: The research was carried out for S. scardica herb of different origins (Albania, Bulgaria, North Macedonia, and Türkiye). Identification of compounds was performed using the HPLC/ESI-QTOF-MS method; phenolic acids and flavonoids were determined spectrophotometrically. The antioxidant activity of methanol extracts from studied herbs was determined using the Folin–Ciocalteu, DPPH, and FRAP methods, and the antimicrobial activity was evaluated using the broth microdilution method in accordance with the guidelines of the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Results: We demonstrated the presence 18–20 active compounds, depending on the origin of the raw material, with verbascoside being the predominant compound in all samples. The raw material was characterized by significant polyphenol content and high antioxidant activity. DPPH tests revealed the highest antioxidant activity, ranging from 86.5% to 87.9%, in samples from Bulgaria, North Macedonia, and Türkiye, and the latter showed the strongest antimicrobial activity, particularly against Gram-positive pathogens and Candida spp. Conclusions: This research is the first report comparing the chemical composition and biological activity of S. scardica raw material of different origins. Our findings indicate that S. scardica herb extracts have significant phytotherapeutic potential, although this varies depending on the origin of the raw material, and point to the need for further research on this plant material, particularly in terms of the level of active compounds and their possible synergistic effects with conventional drugs, as well as the need for standardization. Full article
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30 pages, 883 KiB  
Review
From Block-Oriented Models to the Koopman Operator: A Comprehensive Review on Data-Driven Chemical Reactor Modeling
by Mustapha Kamel Khaldi, Mujahed Al-Dhaifallah, Ibrahim Aljamaan, Fouad Mohammad Al-Sunni, Othman Taha and Abdullah Alharbi
Mathematics 2025, 13(15), 2411; https://doi.org/10.3390/math13152411 - 26 Jul 2025
Viewed by 331
Abstract
Some chemical reactors exhibit coupled dynamics with multiple equilibrium points and strong nonlinearities. The accurate modeling of these dynamics is crucial to optimal control and increasing the reactor’s economic performance. While neural networks can effectively handle complex nonlinearities, they sacrifice interpretability. Alternatively, block-oriented [...] Read more.
Some chemical reactors exhibit coupled dynamics with multiple equilibrium points and strong nonlinearities. The accurate modeling of these dynamics is crucial to optimal control and increasing the reactor’s economic performance. While neural networks can effectively handle complex nonlinearities, they sacrifice interpretability. Alternatively, block-oriented Hammerstein–Wiener models and Koopman operator-based linear predictors combine nonlinear representation with linear dynamics, offering a gray-box identification approach. This paper comprehensively reviews recent advancements in both the Hammerstein–Wiener and Koopman operator methods and benchmarks their accuracy against neural network-based approaches to modeling a large-scale industrial Fluid Catalytic Cracking fractionator. Furthermore, Monte Carlo simulations are employed to validate performance under varying signal-to-noise ratios. The results demonstrate that the Koopman bilinear model significantly outperforms the other methods in terms of accuracy and robustness. Full article
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29 pages, 3064 KiB  
Review
Inelastic Electron Tunneling Spectroscopy of Molecular Electronic Junctions: Recent Advances and Applications
by Hyunwook Song
Crystals 2025, 15(8), 681; https://doi.org/10.3390/cryst15080681 - 26 Jul 2025
Viewed by 394
Abstract
Inelastic electron tunneling spectroscopy (IETS) has emerged as a powerful vibrational spectroscopy technique for molecular electronic junctions, providing unique insights into molecular vibrations and electron–phonon coupling at the nanoscale. In this review, we present a comprehensive overview of IETS in molecular junctions, tracing [...] Read more.
Inelastic electron tunneling spectroscopy (IETS) has emerged as a powerful vibrational spectroscopy technique for molecular electronic junctions, providing unique insights into molecular vibrations and electron–phonon coupling at the nanoscale. In this review, we present a comprehensive overview of IETS in molecular junctions, tracing its development from foundational principles to the latest advances. We begin with the theoretical background, detailing the mechanisms by which inelastic tunneling processes generate vibrational fingerprints of molecules, and highlighting how IETS complements optical spectroscopies by accessing electrically driven vibrational excitations. We then discuss recent progress in experimental techniques and device architectures that have broadened the applicability of IETS. Central focus is given to emerging applications of IETS over the last decade: molecular sensing (identification of chemical bonds and conformational changes in junctions), thermoelectric energy conversion (probing vibrational contributions to molecular thermopower), molecular switches and functional devices (monitoring bias-driven molecular state changes via vibrational signatures), spintronic molecular junctions (detecting spin excitations and spin–vibration interplay), and advanced data analysis approaches such as machine learning for interpreting complex tunneling spectra. Finally, we discuss current challenges, including sensitivity at room temperature, spectral interpretation, and integration into practical devices. This review aims to serve as a thorough reference for researchers in physics, chemistry, and materials science, consolidating state-of-the-art understanding of IETS in molecular junctions and its growing role in molecular-scale device characterization. Full article
(This article belongs to the Special Issue Advances in Multifunctional Materials and Structures)
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15 pages, 10697 KiB  
Article
Simple and Rapid Fabrication of Hydrophobic Coatings by a One-Step Spraying Method and Its Properties
by Rui Xu, Yue Yu, Ben Peng, Guanghua Lu, Xiujun Xing, Changsheng Yue and Lei Zhang
Coatings 2025, 15(8), 872; https://doi.org/10.3390/coatings15080872 - 25 Jul 2025
Viewed by 327
Abstract
This study employed sodium laurate solution as the raw material to fabricate superhydrophobic coatings on cement-based substrates via a facile one-step spraying method. To optimize the processing parameters, the influence of solution concentration on substrate wettability was investigated, leading to the identification of [...] Read more.
This study employed sodium laurate solution as the raw material to fabricate superhydrophobic coatings on cement-based substrates via a facile one-step spraying method. To optimize the processing parameters, the influence of solution concentration on substrate wettability was investigated, leading to the identification of the optimal concentration. Subsequently, superhydrophobic coatings were fabricated under these optimized conditions, and their wettability, mechanical durability, chemical corrosion resistance, and surface repairability were systematically characterized. The results revealed that the coating fabricated with a 0.3% sodium laurate solution exhibited an obvious regular, flaky, rough microstructure, achieving a water contact angle (WCA) of 154° ± 2° and a sliding angle (SA) of 2.9°. The coating demonstrated superhydrophobicity (WCA > 150° and SA < 10°), self-cleaning capability, mechanical durability, chemical corrosion resistance, and environmental stability; furthermore, the abraded surface can be restored to be superhydrophobic by simple and rapid repair. Full article
(This article belongs to the Section Surface Characterization, Deposition and Modification)
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