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Search Results (262)

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Keywords = MW synthesis

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46 pages, 1449 KB  
Review
MXenes in Solid-State Batteries: Multifunctional Roles from Electrodes to Electrolytes and Interfacial Engineering
by Francisco Márquez
Batteries 2025, 11(10), 364; https://doi.org/10.3390/batteries11100364 - 2 Oct 2025
Abstract
MXenes, a rapidly emerging family of two-dimensional transition metal carbides and nitrides, have attracted considerable attention in recent years for their potential in next-generation energy storage technologies. In solid-state batteries (SSBs), they combine metallic-level conductivity (>103 S cm−1), adjustable surface [...] Read more.
MXenes, a rapidly emerging family of two-dimensional transition metal carbides and nitrides, have attracted considerable attention in recent years for their potential in next-generation energy storage technologies. In solid-state batteries (SSBs), they combine metallic-level conductivity (>103 S cm−1), adjustable surface terminations, and mechanical resilience, which makes them suitable for diverse functions within the cell architecture. Current studies have shown that MXene-based anodes can deliver reversible lithium storage with Coulombic efficiencies approaching ~98% over 500 cycles, while their use as conductive additives in cathodes significantly improves electron transport and rate capability. As interfacial layers or structural scaffolds, MXenes effectively buffer volume fluctuations and suppress lithium dendrite growth, contributing to extended cycle life. In solid polymer and composite electrolytes, MXene fillers have been reported to increase Li+ conductivity to the 10−3–10−2 S cm−1 range and enhance Li+ transference numbers (up to ~0.76), thereby improving both ionic transport and mechanical stability. Beyond established Ti-based systems, double transition metal MXenes (e.g., Mo2TiC2, Mo2Ti2C3) and hybrid heterostructures offer expanded opportunities for tailoring interfacial chemistry and optimizing energy density. Despite these advances, large-scale deployment remains constrained by high synthesis costs (often exceeding USD 200–400 kg−1 for Ti3C2Tx at lab scale), restacking effects, and stability concerns, highlighting the need for greener etching processes, robust quality control, and integration with existing gigafactory production lines. Addressing these challenges will be crucial for enabling MXene-based SSBs to transition from laboratory prototypes to commercially viable, safe, and high-performance energy storage systems. Beyond summarizing performance, this review elucidates the mechanistic roles of MXenes in SSBs—linking lithiophilicity, field homogenization, and interphase formation to dendrite suppression at Li|SSE interfaces, and termination-assisted salt dissociation, segmental-motion facilitation, and MWS polarization to enhanced electrolyte conductivity—thereby providing a clear design rationale for practical implementation. Full article
(This article belongs to the Collection Feature Papers in Batteries)
24 pages, 3089 KB  
Article
Optimal Sizing of a Wind-Powered Green Ammonia Plant for Maritime Fuel Supply—A Case in the Greater Bay Area
by Yimiao Gu and Weihao Lan
Energies 2025, 18(19), 5157; https://doi.org/10.3390/en18195157 - 28 Sep 2025
Abstract
Green ammonia has emerged as a promising alternative fuel for maritime decarbonization, owing to its carbon-free combustion, favorable volumetric energy density, and well-established logistics infrastructure compared to other alternatives. However, critical gaps persist in the development of an integrated fuel supply framework, which [...] Read more.
Green ammonia has emerged as a promising alternative fuel for maritime decarbonization, owing to its carbon-free combustion, favorable volumetric energy density, and well-established logistics infrastructure compared to other alternatives. However, critical gaps persist in the development of an integrated fuel supply framework, which hinders the large-scale adoption of ammonia-fueled vessels. Therefore, this paper proposes an onshore wind-powered green ammonia plant located along the Gaolan–Yangpu feeder route. The plant comprises PEM electrolysis, nitrogen separation, Haber–Bosch synthesis, and storage facilities. An optimal plant configuration is subsequently derived through hourly simulations based on wind power generation and a priority-based capacity expansion algorithm. Key findings indicate that a stable ammonia supply—synchronized with monsoon wind patterns and capable of fueling vessels with 10 MW propulsion systems consuming around 680 tons per fortnight—requires a 72 MW onshore wind farm, a 63 MW PEM electrolyzer, 3.6 MW of synthesis facility, and 3205 tons of storage. This configuration yields a levelized cost of ammonia (LCOA) of approximately USD 700/ton, with wind turbines and electrolyzers (including replacement costs) accounting for over 70% of the total cost. Sensitivity analysis further shows that wind turbine and electrolyzer prices are the primary factors affecting ammonia costs. Although variations in operational parameters may significantly alter final configuration, they cause only minor (±1%) fluctuations in the levelized cost without significantly altering its overall trend. Full article
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19 pages, 3327 KB  
Article
Design and Research of High-Energy-Efficiency Underwater Acoustic Target Recognition System
by Ao Ma, Wenhao Yang, Pei Tan, Yinghao Lei, Liqin Zhu, Bingyao Peng and Ding Ding
Electronics 2025, 14(19), 3770; https://doi.org/10.3390/electronics14193770 - 24 Sep 2025
Viewed by 262
Abstract
Recently, with the rapid development of underwater resource exploration and underwater activities, underwater acoustic (UA) target recognition has become crucial in marine resource exploration. However, traditional underwater acoustic recognition systems face challenges such as low energy efficiency, poor accuracy, and slow response times. [...] Read more.
Recently, with the rapid development of underwater resource exploration and underwater activities, underwater acoustic (UA) target recognition has become crucial in marine resource exploration. However, traditional underwater acoustic recognition systems face challenges such as low energy efficiency, poor accuracy, and slow response times. Systems for UA target recognition using deep learning networks have garnered widespread attention. Convolutional neural network (CNN) consumes significant computational resources and energy during convolution operations, which exacerbates the issues of energy consumption and complicates edge deployment. This paper explores a high-energy-efficiency UA target recognition system. Based on the DenseNet CNN, the system uses fine-grained pruning for sparsification and sparse convolution computations. The UA target recognition CNN was deployed on FPGAs and chips to achieve low-power recognition. Using the noise-disturbed ShipsEar dataset, the system reaches a recognition accuracy of 98.73% at 0 dB signal-to-noise ratio (SNR). After 50% fine-grained pruning, the accuracy is 96.11%. The circuit prototype on FPGA shows that the circuit achieves an accuracy of 95% at 0 dB SNR. This work implements the circuit design and layout of the UA target recognition chip based on a 65 nm CMOS process. DC synthesis results show that the power consumption is 90.82 mW, and the single-target recognition time is 7.81 ns. Full article
(This article belongs to the Special Issue Digital Intelligence Technology and Applications)
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24 pages, 8771 KB  
Article
Thiamethoxam Sensing Using Gelatin Carbon Dots: Influence of Synthesis and Purification Methods
by Mayara Martins Caetano and Renata Galvão de Lima
Chemosensors 2025, 13(9), 326; https://doi.org/10.3390/chemosensors13090326 - 1 Sep 2025
Viewed by 576
Abstract
This innovative study introduces an eco-conscious and cost-effective approach to synthesizing gelatin-based carbon dots (CDs) via two distinctive methods: hydrothermal processing in a muffle furnace (CDs-MF) and domestic microwave (CDs-MW). Both strategies harness natural, low-cost materials and prioritize simplicity, sustainability, and environmental friendliness, [...] Read more.
This innovative study introduces an eco-conscious and cost-effective approach to synthesizing gelatin-based carbon dots (CDs) via two distinctive methods: hydrothermal processing in a muffle furnace (CDs-MF) and domestic microwave (CDs-MW). Both strategies harness natural, low-cost materials and prioritize simplicity, sustainability, and environmental friendliness, culminating in effective fluorescent sensing of the pesticide thiamethoxam (TMX). For the hydrothermal route, the investigation explores two purification approaches—ultracentrifugation (CDs-MF-C) and 0.22 µm syringe filtration (CDs-MF-F)—while the microwave-derived CDs (CDs-MW) undergo dialysis alone. This study aims to investigate how synthesis and purification impact the CDs structural, morphological, and photophysical characteristics. The difference in size was obtained from transmission electron microscopy (TEM): 30–40 nm for CDs-MF-C, 12–15 nm for CDs-MF-F, and 3–6 nm for CDs-MW. Fluorescence emission performance reveals that CDs-MF-F performs a fluorescence quantum yield of 27%, CDs-MF-C at 23%, and CDs-MW at a modest 3%. All variants exhibit TMX detection via fluorescence quenching through the inner filter effect (IFE). Analytically, CDs-MF-C stands out with the lowest detection limit (LOD = 0.396 ppm) and quantification limit (LOQ = 1.317 ppm), followed by CDs-MF-F (LOD = 0.475 ppm; LOQ = 1.585 ppm) and CDs-MW (LOD = 0.549 ppm; LOQ = 1.831 ppm). These findings emphasize the unique interplay between the synthesis pathway, purification strategy, and functional performance, demonstrating the critical importance of tuning structural properties for optimizing carbon-dot sensors. Full article
(This article belongs to the Special Issue The Recent Progress and Applications of Optical Chemical Sensors)
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31 pages, 3210 KB  
Systematic Review
The Mind-Wandering Phenomenon While Driving: A Systematic Review
by Gheorghe-Daniel Voinea, Florin Gîrbacia, Răzvan Gabriel Boboc and Cristian-Cezar Postelnicu
Information 2025, 16(8), 681; https://doi.org/10.3390/info16080681 - 8 Aug 2025
Viewed by 1206
Abstract
Mind wandering (MW) is a significant safety risk in driving, yet research on its scope, underlying mechanisms, and mitigation strategies remains fragmented across disciplines. In this review guided by the PRISMA framework, we analyze findings from 64 empirical studies to address these factors. [...] Read more.
Mind wandering (MW) is a significant safety risk in driving, yet research on its scope, underlying mechanisms, and mitigation strategies remains fragmented across disciplines. In this review guided by the PRISMA framework, we analyze findings from 64 empirical studies to address these factors. The presented study quantifies the prevalence of MW in naturalistic and simulated driving environments and shows its impact on driving behaviors. We document its negative effects on braking reaction times and lane-keeping consistency, and we assess recent advancements in objective detection methods, including EEG signatures, eye-tracking metrics, and physiological markers. We also identify key cognitive and contextual risk factors, including high perceived risk, route familiarity, and driver fatigue, which increase MW episodes. Also, we survey emergent countermeasures, such as haptic steering wheel alerts and adaptive cruise control perturbations, designed to sustain driver engagement. Despite these advancements, the MW research shows persistent challenges, including methodological heterogeneity that limits cross-study comparisons, a lack of real-world validation of detection algorithms, and a scarcity of long-term field trials of interventions. Our integrated synthesis, therefore, outlines a research agenda prioritizing harmonized measurement protocols, on-road algorithm deployment, and rigorous evaluation of countermeasures under naturalistic driving conditions. Full article
(This article belongs to the Section Information and Communications Technology)
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14 pages, 3397 KB  
Article
The Capacitive Property Enhancement of CoFeP-Ni(OH)2/Nickel Foam Electrodes via an Interfacial Integration Strategy for Asymmetric Supercapacitors
by Meiying Cui, Meiying Pei and Seok Kim
Molecules 2025, 30(14), 2986; https://doi.org/10.3390/molecules30142986 - 16 Jul 2025
Viewed by 546
Abstract
We report the fabrication of CoFeP-Ni(OH)2/nickel foam (NF) composite electrodes via a two-step strategy involving the hydrothermal synthesis of Ni(OH)2 on nickel foam followed by the electrochemical deposition of CoFeP. The integration of the Ni(OH)2 interlayer not only provides [...] Read more.
We report the fabrication of CoFeP-Ni(OH)2/nickel foam (NF) composite electrodes via a two-step strategy involving the hydrothermal synthesis of Ni(OH)2 on nickel foam followed by the electrochemical deposition of CoFeP. The integration of the Ni(OH)2 interlayer not only provides a structurally robust interface but also facilitates synergistic redox activity, thereby significantly boosting the pseudocapacitive behavior of the electrode. Comparative analysis with bare CoFeP/NF reveals that the presence of the Ni(OH)2 layer contributes to enhanced charge transfer efficiency and an increased electroactive surface area. Among the samples prepared under varying deposition cycles, the optimized CoFeP-Ni(OH)2/NF electrode exhibits a high areal capacitance of 4244 mF cm−2 at 2 mA cm−2. Furthermore, an asymmetric supercapacitor device assembled with CoFeP-Ni(OH)2/NF as the positive electrode and activated carbon as the negative electrode delivers a maximum energy density of 0.19 mWh cm−2 at a power density of 0.37 mW cm−2 and excellent cycling stability, retaining 72% of its initial capacitance after 5000 cycles at a high current density of 8 mA cm−2. Full article
(This article belongs to the Special Issue Inorganic Chemistry in Asia)
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21 pages, 2042 KB  
Article
Ultrasound and Microwave-Assisted Synthesis and Antidiabetic and Hematopoietic Activity of Diphenhydramine Derivatives
by Anuar Dauletbakov, Yelizaveta Belyankova, Saniya Assylbekova, Darya Zolotareva, Sarah Bayazit, Layilya Baktybayeva, Ulan Kemelbekov, Valentina Yu, Nailya Ibragimova and Alexey Zazybin
Molecules 2025, 30(14), 2967; https://doi.org/10.3390/molecules30142967 - 15 Jul 2025
Viewed by 458
Abstract
This study presents the synthesis and antidiabetic and hematopoietic activity of ionic compounds based on 2-(diphenylmethoxy)-N,N-dimethylethanamine (diphenhydramine). Synthesis is carried out under ultrasonic (US) and microwave (MW) irradiation as well as using a conventional method (thermal activation). The synthesized [...] Read more.
This study presents the synthesis and antidiabetic and hematopoietic activity of ionic compounds based on 2-(diphenylmethoxy)-N,N-dimethylethanamine (diphenhydramine). Synthesis is carried out under ultrasonic (US) and microwave (MW) irradiation as well as using a conventional method (thermal activation). The synthesized ionic compounds have been tested for antidiabetic effect according to the inhibitory action against α-glucosidase and α-amylase (in vitro). All the synthesized derivatives of diphenhydramine showed higher inhibitory activity against α-glucosidase than commercially available diphenhydramine hydrochloride. Moreover, two of them, 1m (66.9%) and 1k (64.2%), had a greater inhibitory activity than the reference drug acarbose (51.8%). The hematopoietic activity was studied in albino laboratory female rats (in vivo). The compounds 1b, 1f, and 1k can restore immune blood cells (hematopoietic activity), equal to or exceeding that of the commercially available diphenhydramine hydrochloride and control (methyluracil). Full article
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12 pages, 2721 KB  
Article
Conjugated Polyaniline–Phytic Acid Polymer Derived 3D N, P-Doped Porous Carbon as a Metal-Free Electrocatalyst for Zn–Air Batteries
by Wanting Xiong, Yifan Kong, Jiangrong Xiao, Tingting Wang and Xiaoli Chen
Catalysts 2025, 15(7), 683; https://doi.org/10.3390/catal15070683 - 14 Jul 2025
Viewed by 571
Abstract
The development of cost-effective and scalable air/oxygen electrode materials is crucial for the advancement of Zn–air batteries (ZABs). Porous carbon materials doped with heteroatoms have attracted considerable attention in energy and environmental fields because of their tunable nanoporosity and high electrical conductivity. In [...] Read more.
The development of cost-effective and scalable air/oxygen electrode materials is crucial for the advancement of Zn–air batteries (ZABs). Porous carbon materials doped with heteroatoms have attracted considerable attention in energy and environmental fields because of their tunable nanoporosity and high electrical conductivity. In this work, we report the synthesis of a three-dimensional (3D) N and P co-doped porous carbon (PA@pDC-1000), derived from a conjugated polyaniline–phytic acid polymer. The cross-linked, rigid conjugated polymeric framework plays a crucial role in maintaining the integrity of micro- and mesoporous structures and promoting graphitization during carbonization. As a result, the material exhibits a hierarchical pore structure, a high specific surface area (1045 m2 g−1), and a large pore volume (1.02 cm3 g−1). The 3D N, P co-doped PA@pDC-1000 catalyst delivers a half-wave potential of 0.80 V (vs. RHE) and demonstrates a higher current density compared to commercial Pt/C. A primary ZAB utilizing this material achieves an open-circuit voltage of 1.51 V and a peak power density of 217 mW cm−2. This metal-free, self-templating presents a scalable route for the generating and producing of high-performance oxygen reduction reaction catalysts for ZABs. Full article
(This article belongs to the Special Issue Electrocatalysis and Photocatalysis in Redox Flow Batteries)
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14 pages, 1518 KB  
Article
Synthesis of Multifunctional Hyperbranched Polymers via Atom Transfer Radical Self-Condensing Vinyl Polymerization for Applications in Polyurethane-Based Anion Exchange Membranes
by Nhat Hong Nguyen, Chih-Feng Huang and Tongsai Jamnongkan
Polymers 2025, 17(14), 1930; https://doi.org/10.3390/polym17141930 - 13 Jul 2025
Viewed by 649
Abstract
Anion exchange membranes (AEMs) are vital for electrochemical energy devices such as alkaline fuel cells and water electrolyzers, enabling the use of non-precious metal catalysts despite challenges from alkaline degradation. Hyperbranched polymers (hbPs) with their globular structure, high functional group density, and simple [...] Read more.
Anion exchange membranes (AEMs) are vital for electrochemical energy devices such as alkaline fuel cells and water electrolyzers, enabling the use of non-precious metal catalysts despite challenges from alkaline degradation. Hyperbranched polymers (hbPs) with their globular structure, high functional group density, and simple synthesis, offer a promising platform for enhancing transport and stability. In this study, multifunctional hbPs were synthesized from 4-vinylbenzyl chloride (VBC) and 2-hydroxyethyl methacrylate (HEMA) via atom transfer radical self-condensing vinyl polymerization (ATR-SCVP) and crosslinked into polyurethane-based AEMs. Characterization confirmed successful copolymerization and crosslinking, with excellent alkaline stability. Membranes crosslinked with higher molecular weight (MW) and VBC-richer hbPs (e.g., OH-hbP1-PU) exhibited high water uptake (75%) but low ion-exchange capacity (1.54 mmol/g) and conductivity (186 µS/cm), attributed to steric hindrance and insufficient ionic network connectivity. In contrast, OH-hbP2-PU exhibited optimal properties, with the highest OH conductivity (338 µS/cm) and IEC (2.64 mmol/g), highlighting a balanced structure for efficient ion transport. This work offers a tunable strategy for high-performance AEM development through tailored hbP architecture. Full article
(This article belongs to the Special Issue Development and Innovation of Stimuli-Responsive Polymers)
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21 pages, 8232 KB  
Article
Investigation of Complex ZnO-Porous Silicon Structures with Different Dimensions Obtained by Low-Temperature Synthesis
by Rashid Zhapakov, Danatbek Murzalinov, Mikhail Begunov, Tatyana Seredavina, Alena Gagarina, Yulia Spivak, Vyacheslav Moshnikov, Elena A. Dmitriyeva, Petr Osipov and Ainagul Kemelbekova
Processes 2025, 13(7), 2099; https://doi.org/10.3390/pr13072099 - 2 Jul 2025
Viewed by 537
Abstract
The study of the processes of low-temperature synthesis of one-dimensional particles, which are the basis for two- and three-dimensional structures, is relevant for materials science. The modified metal-stimulated electrochemical etching method made it possible to synthesize silicon nanowires with an average thickness of [...] Read more.
The study of the processes of low-temperature synthesis of one-dimensional particles, which are the basis for two- and three-dimensional structures, is relevant for materials science. The modified metal-stimulated electrochemical etching method made it possible to synthesize silicon nanowires with an average thickness of about 292.6 nm. Scanning electron microscopy has shown the formation of nanowires, flower-like structures, and clusters of matter after the deposition of zinc oxide on the porous surface. The hexagonal structure of ZnO crystallites was determined by X-ray diffraction spectroscopy. Studies of the initial sample by electron paramagnetic resonance (EPR) spectroscopy revealed a narrow signal in the center of the spectrum. The subtraction of the EPR spectra with a sequential increase in microwave power up to 8 mW shows the absence of saturation of the signal. This indicates an almost free flow of charges through the surface nanostructures under the influence of an external field. Heat treatment in an air atmosphere at 300 °C caused a significant increase in the intensity of the EPR spectrum. This led to an increase in the intensity of charge transfer through paramagnetic centers. Full article
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13 pages, 703 KB  
Article
Proteolytic Activity Inhibition in Gingival Fluid by Cysteine Protease Inhibitors Obtained from Egg White and Fallopia japonica Extract: An In Vitro Study
by Maciej Siewiński, Maciej Dobrzyński, Krzysztof Gołąb, Maciej Janeczek, Łukasz Nieradko, Barbara Bażanów, Andrzej Rapak, Marius Boariu, Stefan-Ioan Stratul, Alla Belova, Sorina Mihaela Solomon, Renata Samulak and Monika Machoy
Biomedicines 2025, 13(7), 1545; https://doi.org/10.3390/biomedicines13071545 - 25 Jun 2025
Viewed by 653
Abstract
Background/Objectives: Gingipains produced by P. gingivalis have been shown to be directly related to periodontal tissue degradation and are significant molecular targets in therapy of periodontitis. Blocking the activity of these enzymes should reduce survival of this pathogen and mitigate the effects [...] Read more.
Background/Objectives: Gingipains produced by P. gingivalis have been shown to be directly related to periodontal tissue degradation and are significant molecular targets in therapy of periodontitis. Blocking the activity of these enzymes should reduce survival of this pathogen and mitigate the effects of inflammation in periodontitis. Therefore, gingipains inhibitors and specific antibodies could be recommended in the treatment of periodontitis. Cysteine peptidase inhibitors can be obtained by chemical synthesis, or isolated from natural raw materials. This research has the following aims: 1. to analyze in vitro the inhibition of cysteine protease activity in the gingival crevicular fluid (GCF) and 2. to compare the toxicity of natural raw inhibitors (obtained from Fallopia japonica plant and egg white) with chlorhexidine (CHX) using an MTS viability test. Methods: Samples of GCF were collected from healthy (N = 17) individuals and (N = 65) periodontal patients. Cysteine peptidase activity was inhibited by adding a solution of cystatin from egg white (with 20% glycerol), or cystatin from knotweed, or low molecular weight inhibitors (MW < 3 kDa) from egg white and knotweed against Nα-Benzoyl-DL-arginine 4-nitroanilide hydrochloride. Results: There was a statistically significant difference between the inhibition means of cysteine protease activity for the five groups (p < 0.001). Means for the four groups of patients with periodontitis were not statistically significant different from each other (p = 0.320). The inhibition rates were higher in periodontitis patients. The toxicity of knotweed cystatin inhibitor was several times lower than the toxicity of E-64d, and of CHX. Conclusion: Cysteine protease inhibitors isolated from egg or plants were non-toxic, effectively inhibited the activity of cysteine proteases in GCF, and may be a promising alternative to more toxic standard antimicrobials (CHX) in preventing periodontal tissue breakdown. Full article
(This article belongs to the Section Biomedical Engineering and Materials)
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13 pages, 1100 KB  
Article
Easy ROMP of Quinine Derivatives Toward Novel Chiral Polymers That Discriminate Mandelic Acid Enantiomers
by Mariusz Majchrzak, Karol Kacprzak, Marta Piętka, Jerzy Garbarek and Katarzyna Taras-Goślińska
Polymers 2025, 17(12), 1661; https://doi.org/10.3390/polym17121661 - 15 Jun 2025
Viewed by 747
Abstract
A novel and general approach to the practical ROMP polymerization of cinchona alkaloid derivatives providing novel hybrid materials having quinine attached on a poly(norbornene-5,6-dicarboxyimide) matrix is presented. The concept involves an easy modification of quinine (in general, any cinchona alkaloid) toward clickable 9-azide [...] Read more.
A novel and general approach to the practical ROMP polymerization of cinchona alkaloid derivatives providing novel hybrid materials having quinine attached on a poly(norbornene-5,6-dicarboxyimide) matrix is presented. The concept involves an easy modification of quinine (in general, any cinchona alkaloid) toward clickable 9-azide that reacts with N-propargyl-cis-5-norbornene-exo-2,3-dicarboxylic imide in Cu(I)-catalyzed Huisgen cycloaddition (click chemistry). The resulting monomers undergo a controllable ROMP reaction that leads to novel polymers of a desired length and solubility. This sequence allows for the facile preparation of a regularly decorated polymeric material having one quinine moiety per single mer of the polymer chain inaccessible using typical immobilization methods. A poly(norbornene-5,6-dicarboxyimide) type of polymeric matrix was selected due to the high reactivity of the exo-norbornene motif in Ru(II)-catalyzed ROMP and its chemical and thermal stability as well as convenient, scalable access from inexpensive cis-5-norbornene-exo-2,3-dicarboxylic anhydride (‘one-pot’ Diels–Alder reaction of dicyclopentadiene and maleic anhydride). An appropriate combination of a Grubbs catalyst, Ru(II) (G1, G2), and ROMP conditions allowed for the efficient synthesis of well-defined soluble polymers with mass parameters in the range Mn = 2.24 × 104 – 2.26 × 104 g/mol and Mw = 2.90 × 104–3.05 × 104 g/mol with good polydispersity, ĐM = 1.32–1.35, and excellent thermal stability (up to 309°C Td10). Spectroscopic studies (NMR and electronic circular dichroism (ECD)) of these products revealed a linear structure with the slight advantage of a trans-configuration of an olefinic double bond. The resulting short-chain polymer discriminates mandelic acid enantiomers with a preference for the (R)-stereoisomer in spectrofluorimetric assays. This concept seems to be rather general with respect to other molecules dedicated to incorporation into the poly(norbornene-5,6-dicarboxyimide) chain. Full article
(This article belongs to the Section Polymer Chemistry)
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17 pages, 2081 KB  
Article
Efficiency of Microwave-Assisted Surface Grafting of Ni and Zn Clusters on TiO2 as Cocatalysts for Solar Light Degradation of Cyanotoxins
by Andraž Šuligoj, Mallikarjuna Nadagouda, Gregor Žerjav, Albin Pintar, Dionysios D. Dionysiou and Nataša Novak Tušar
Catalysts 2025, 15(6), 590; https://doi.org/10.3390/catal15060590 - 14 Jun 2025
Viewed by 709
Abstract
Herein, we report on the synthesis of Ni and Zn clusters on the surface of TiO2 as well as their bimetallic NiZn analogs. The materials were prepared by incipient wet impregnation of colloidal TiO2 followed by microwave (MW) irradiation to graft [...] Read more.
Herein, we report on the synthesis of Ni and Zn clusters on the surface of TiO2 as well as their bimetallic NiZn analogs. The materials were prepared by incipient wet impregnation of colloidal TiO2 followed by microwave (MW) irradiation to graft the clusters to TiO2 surface. The materials were further immobilized onto glass slides and exhibited high surface area, high mechanical stability, and porosity with accessible pores. The main species responsible for visible light degradation of microcystin LR via the interface charge transfer (IFCT) of excited e to surface metal clusters were found to be O2•− and h+. The optimal nominal grafting concentration was 0.5 wt.% for Ni and 1.0 wt.% for Zn, while for the bimetal modification (NiZn), the optimal nominal concentration was 0.5 wt.%. Compared to monometallic, bimetallic grafting showed a lower kinetic constant, albeit still improved compared to bare TiO2. Bimetal-modified titania showed a lower photocurrent compared to single metal-grafted TiO2 and poorer interfacial charge transport, namely, more recombination sites—possibly at the interface between the Ni and Zn domains. This work highlights the efficiency of using MW irradiation for grafting sub-nano-sized metallic species to TiO2 in a homogeneous way. However, further strategies using MW irradiation for the structural design of bimetallic cocatalysts can be implemented in the future. Full article
(This article belongs to the Special Issue Commemorative Special Issue for Prof. Dr. Dion Dionysiou)
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19 pages, 2334 KB  
Article
One-Pot Microwave-Assisted Synthesis of Fluorescent Carbon Dots from Tomato Industry Residues with Antioxidant and Antibacterial Activities
by Patrícia D. Barata, Alexandra I. Costa, Sónia Martins, Magda C. Semedo, Bruno G. Antunes and José V. Prata
Biomass 2025, 5(2), 35; https://doi.org/10.3390/biomass5020035 - 10 Jun 2025
Viewed by 1604
Abstract
Tomato waste (TW) was employed as a sustainable source for the synthesis of fluorescent carbon dots (CDs) via a microwave-assisted hydrothermal carbonization (Mw-HTC) method, aiming at its valorization. Several amines were used as nitrogen additives to enhance the fluorescence quantum yield (QY) of [...] Read more.
Tomato waste (TW) was employed as a sustainable source for the synthesis of fluorescent carbon dots (CDs) via a microwave-assisted hydrothermal carbonization (Mw-HTC) method, aiming at its valorization. Several amines were used as nitrogen additives to enhance the fluorescence quantum yield (QY) of CDs, and a set of reaction conditions, including additive/TW mass ratio (0.04–0.32), dwell time (15–60 min), and temperature (200–230 °C) of the HTC process, were scrutinized. The structural analysis of the tomato waste carbon dots (TWCDs) was undertaken by FTIR and 1H NMR techniques, revealing their most relevant features. In solid state, transmission electron microscopy (TEM) analysis showed the presence of nearly spherical nanoparticles with an average lateral size of 8.1 nm. Likewise, the topographical assessment by atomic force microscopy (AFM) also indicated particles’ heights between 3 and 10 nm. Their photophysical properties, revealed by UV–Vis, steady-state, and time-resolved fluorescence spectroscopies, are fully discussed. Higher photoluminescent quantum yields (up to 0.08) were attained when the biomass residues were mixed with organic aliphatic amines during the Mw-HTC process. Emission tunability is a characteristic feature of these CDs, which display an intensity average fluorescence lifetime of 8 ns. The new TWCDs demonstrated good antioxidant properties by the ABTS radical cation method (75% inhibition at TWCDs’ concentration of 5 mg/mL), which proved to be related to the dwell time used in the CDs synthesis. Moreover, the synthesized TWCDs suppressed the growth of Escherichia coli and Staphylococcus aureus at concentrations higher than 2000 μg/mL, encouraging future antibacterial applications. Full article
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37 pages, 6284 KB  
Systematic Review
Valorization of Medical Waste in Cement-Based Construction Materials: A Systematic Review
by M. Murillo, S. Manzano, Y. F. Silva, C. Burbano-García and G. Araya-Letelier
Buildings 2025, 15(10), 1643; https://doi.org/10.3390/buildings15101643 - 13 May 2025
Viewed by 1397
Abstract
Worldwide, the healthcare industry produces massive quantities of medical waste (MW), most of which is incinerated, releasing large quantities of dioxins, mercury, and other pollutants. Despite this, only a limited number of studies have explored the incorporation of MW into construction materials, with [...] Read more.
Worldwide, the healthcare industry produces massive quantities of medical waste (MW), most of which is incinerated, releasing large quantities of dioxins, mercury, and other pollutants. Despite this, only a limited number of studies have explored the incorporation of MW into construction materials, with a special focus on cement-based construction materials (CB-CMs). However, to the best of the authors’ knowledge, no existing review formally structures, summarizes, correlates, and discusses the findings of previous studies on MW in CB-CMs to encourage further research and applications of this promising alternative. Therefore, the added value of this study lies in providing an innovative and critical analysis of existing research on the use of MW in CB-CMs, consolidating and evaluating dispersed findings through a systematic literature review, enhancing understanding of the topic, and identifying knowledge gaps to guide future research. A robust systematic literature review was conducted, encompassing 40 peer-reviewed research articles, retrieved from the Web of Science Core Collection database. The methodology involved a three-stage process: a descriptive analysis of the included articles, the identification and synthesis of key thematic areas, and a critical evaluation of the data to ensure a rigorous and systematic report. The selection criteria prioritized peer-reviewed research articles in English with full text availability published in the last 7 years, explicitly excluding conference papers, book chapters, short reports, and articles not meeting the language or accessibility requirements. The results indicate that the influence of MW in CB-CM varies significantly. For example, while the incorporation of face masks as fiber reinforcement in concrete generally enhances its mechanical and durability properties, the use of gloves is less effective and not always recommended. Finally, it was found that further research is needed in this field due to its novelty. Full article
(This article belongs to the Section Building Materials, and Repair & Renovation)
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