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Search Results (1,028)

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Keywords = UV-Vis absorption studies

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11 pages, 919 KiB  
Article
Dye-Sensitized Solar Cells Application of TiO2 Using Spirulina and Chlorella Algae Extract
by Maria Vitória França Corrêa, Gideã Taques Tractz, Guilherme Arielo Rodrigues Maia, Hagata Emmanuely Slusarski Fonseca, Larissa Oliveira Berbel, Lucas José de Almeida and Everson do Prado Banczek
Colorants 2025, 4(3), 25; https://doi.org/10.3390/colorants4030025 - 4 Aug 2025
Abstract
The present study investigates dye-sensitized solar cells (DSSCs) incorporating natural extracts from the microalgae Spirulina and Chlorella as photosensitizers. TiO2-based electrodes were prepared and immersed in methanolic algae extracts for 24 and 48 h. UV–Vis spectroscopy revealed absorption peaks near 400 [...] Read more.
The present study investigates dye-sensitized solar cells (DSSCs) incorporating natural extracts from the microalgae Spirulina and Chlorella as photosensitizers. TiO2-based electrodes were prepared and immersed in methanolic algae extracts for 24 and 48 h. UV–Vis spectroscopy revealed absorption peaks near 400 nm and 650 nm, characteristic of chlorophyll. Electrochemical analyses, including photochronoamperometry and open-circuit potential, confirmed the photosensitivity and charge transfer capabilities of all systems. The cell sensitized with Chlorella after 48 h of immersion exhibited the highest energy conversion efficiency (0.0184% ± 0.0015), while Spirulina achieved 0.0105% ± 0.0349 after 24 h. Chlorella’s superior performance is attributed to its higher chlorophyll content and enhanced light absorption, facilitating more efficient electron injection and interaction with the TiO2 surface. Although the efficiency remains lower than that of conventional silicon-based solar cells, the results highlight the potential of natural colorants as sustainable and low-cost alternatives for photovoltaic applications. Nonetheless, further, improvements are required, particularly in dye stability and anchorage, to improve device performance. This research reinforces the viability of natural photosensitizers in DSSC technology and supports continued efforts to optimize their application. Full article
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17 pages, 2112 KiB  
Article
Direct Detection of Orthoflavivirus via Gold Nanorod Plasmon Resonance
by Erica Milena de Castro Ribeiro, Bruna de Paula Dias, Cyntia Silva Ferreira, Samara Mayra Soares Alves dos Santos, Rajiv Gandhi Gopalsamy, Estefânia Mara do Nascimento Martins, Cintia Lopes de Brito Magalhães, Flavio Guimarães da Fonseca, Luiz Felipe Leomil Coelho, Cristiano Fantini, Luiz Orlando Ladeira, Lysandro Pinto Borges and Breno de Mello Silva
Sensors 2025, 25(15), 4775; https://doi.org/10.3390/s25154775 - 3 Aug 2025
Viewed by 59
Abstract
Dengue, Zika, yellow fever, chikungunya, and Mayaro arboviruses represent an increasing threat to public health because of the serious infections they cause annually in many countries. Serological diagnosis of these viruses is challenging, making the development of new diagnostic strategies imperative. In this [...] Read more.
Dengue, Zika, yellow fever, chikungunya, and Mayaro arboviruses represent an increasing threat to public health because of the serious infections they cause annually in many countries. Serological diagnosis of these viruses is challenging, making the development of new diagnostic strategies imperative. In this study, we investigated the effectiveness of gold nanorods (GNRs) functionalized with specific anti-dengue and anti-orthoflavivirus antibodies in detecting viral particles. GNRs were created with a length-to-width ratio of up to 5.5, a size of 71.4 ± 6.5 nm, and a light absorption peak at 927 nm, and they were treated with 4 mM polyethyleneimine. These GNRs were attached to a small amount of monoclonal antibodies that target flaviviruses, and the viral particles were detected by measuring the localized surface plasmon resonance using an UV-Vis/NIR spectrometer. The tests found Orthoflavivirus dengue and Orthoflavivirus zikaense in diluted human serum and ground-up mosquitoes, with the lowest detectable amount being 100 PFU/mL. The GNRs described in this study can be used to enhance flavivirus diagnostic tests or to develop new, faster, and more accurate diagnostic techniques. Additionally, the functionalized GNRs presented here are promising for supporting virological surveillance studies in mosquitoes. Our findings highlight a fast and highly sensitive method for detecting Orthoflavivirus in both human and mosquito samples, with a detection limit as low as 100 PFU/mL. Full article
(This article belongs to the Section Biosensors)
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17 pages, 1594 KiB  
Article
Molecular-Level Insights into Meta-Phenylenediamine and Sulfonated Zinc Phthalocyanine Interactions for Enhanced Polyamide Membranes: A DFT and TD-DFT Study
by Ameni Gargouri and Bassem Jamoussi
Polymers 2025, 17(15), 2019; https://doi.org/10.3390/polym17152019 - 24 Jul 2025
Viewed by 285
Abstract
Access to clean water is a pressing global concern and membrane technologies play a vital role in addressing this challenge. Thin-film composite membranes prepared via interfacial polymerization (IPol) using meta-phenylenediamine (MPD) and trimesoyl chloride (TMC) exhibit excellent separation performance, but face limitations such [...] Read more.
Access to clean water is a pressing global concern and membrane technologies play a vital role in addressing this challenge. Thin-film composite membranes prepared via interfacial polymerization (IPol) using meta-phenylenediamine (MPD) and trimesoyl chloride (TMC) exhibit excellent separation performance, but face limitations such as fouling and low hydrophilicity. This study investigated the interaction between MPD and sulfonated zinc phthalocyanine, Zn(SO2)4Pc, as a potential strategy for enhancing membrane properties. Using Density Functional Theory (DFT) and Time-Dependent DFT (TD-DFT), we analyzed the optimized geometries, electronic structures, UV–Vis absorption spectra, FT-IR vibrational spectra, and molecular electrostatic potentials of MPD, Zn(SO2)4Pc, and their complexes. The results show that MPD/Zn(SO2)4Pc exhibits reduced HOMO-LUMO energy gaps and enhanced charge delocalization, particularly in aqueous environments, indicating improved stability and reactivity. Spectroscopic features confirmed strong interactions via hydrogen bonding and π–π stacking, suggesting that Zn(SO2)4Pc can act as a co-monomer or additive during IPol to improve polyamide membrane functionality. A conformational analysis of MPD/Zn(SO2)4Pc was conducted using density functional theory (DFT) to evaluate the impact of dihedral rotation on molecular stability. The 120° conformation was identified as the most stable, due to favorable π–π interactions and intramolecular hydrogen bonding. These findings offer computational evidence for the design of high-performance membranes with enhanced antifouling, selectivity, and structural integrity for sustainable water treatment applications. Full article
(This article belongs to the Special Issue Nanocomposite Polymer Membranes for Advanced Water Treatment)
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17 pages, 3345 KiB  
Article
Novel Tetraphenolic Porphyrazine Capable of MRSA Photoeradication
by Wojciech Szczolko, Eunice Zuchowska, Tomasz Koczorowski, Michal Kryjewski, Jolanta Dlugaszewska and Dariusz T. Mlynarczyk
Molecules 2025, 30(15), 3069; https://doi.org/10.3390/molecules30153069 - 22 Jul 2025
Viewed by 238
Abstract
This work presents the synthesis, characterization and evaluation of physicochemical and biological properties of two new aminoporphyrazine derivatives bearing magnesium(II) cations in their cores and peripheral pyrrolyl groups. The synthesis was carried out in several stages, using classical methods and the Microwave-Assisted Organic [...] Read more.
This work presents the synthesis, characterization and evaluation of physicochemical and biological properties of two new aminoporphyrazine derivatives bearing magnesium(II) cations in their cores and peripheral pyrrolyl groups. The synthesis was carried out in several stages, using classical methods and the Microwave-Assisted Organic Synthesis (MAOS) approach. The obtained compounds were characterized using spectral techniques: UV-Vis spectrophotometry, mass spectrometry, 1H and 13C NMR spectroscopy. The porphyrazine derivatives were tested for their electrochemical properties (CV and DPV), which revealed four redox processes, of which in compound 7 positive shifts of oxidation potentials were observed, resulting from the presence of free phenolic hydroxyl groups. In spectroelectrochemical measurements, changes in UV-Vis spectra associated with the formation of positive-charged states were noted. Photophysical studies revealed the presence of characteristic absorption Q and Soret bands, low fluorescence quantum yields and small Stokes shifts. The efficiency of singlet oxygen generation (ΦΔ) was higher for compound 6 (up to 0.06), but compound 7, despite its lower efficiency (0.02), was distinguished by a better biological activity profile. Toxicity tests using the Aliivibrio fischeri bacteria indicated the lower toxicity of 7 compared to 6. The most promising result was the strong photodynamic activity of porphyrazine 7 against the Methicillin-resistant Stapylococcus aureus (MRSA) strain, leading to a more-than-5.6-log decrease in viable counts after the colony forming units (CFU) after light irradiation. Compound 6 did not show any significant antibacterial activity. The obtained data indicate that porphyrazine 7 is a promising candidate for applications in photodynamic therapy of bacterial infections. Full article
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27 pages, 8396 KiB  
Article
Biosynthesis of Zinc Oxide Nanostructures Using Leaf Extract of Azadirachta indica: Characterizations and In Silico and Nematicidal Potentials
by Gulrana Khuwaja, Anis Ahmad Chaudhary, Abadi M. Mashlawi, Abdullah Ali Alamri, Faris Alfifi, Kahkashan Anjum, Md Shamsher Alam, Mohammad Intakhab Alam, Syed Kashif Ali, Nadeem Raza, Mohamed A. M. Ali and Mohd Imran
Catalysts 2025, 15(7), 693; https://doi.org/10.3390/catal15070693 - 21 Jul 2025
Viewed by 465
Abstract
Biosynthesized ZnO nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet–visible (UV-vis) spectroscopy, and Fourier transform–infrared (FT-IR) spectroscopy. XRD confirmed a hexagonal wurtzite phase with an average crystallite size of 36.44 nm, while UV-vis spectroscopy showed [...] Read more.
Biosynthesized ZnO nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet–visible (UV-vis) spectroscopy, and Fourier transform–infrared (FT-IR) spectroscopy. XRD confirmed a hexagonal wurtzite phase with an average crystallite size of 36.44 nm, while UV-vis spectroscopy showed a distinct absorption peak at 321 nm. The Zeta potential of the ZnO nanostructures was −24.28 mV, indicating high stability in suspension, which is essential for their dispersion and functionality in biological and environmental applications. The nematicidal activity of ZnO was evaluated in vitro at concentrations of 150, 300, 450, and 600 ppm, with the highest concentration achieving 75.71% mortality of second-stage juveniles (J2s) after 72 h. The calculated LC50 values for the treatments were 270.33 ppm at 72 h. Additionally, molecular docking studies indicated significant interactions between the ZnO nanostructures and nematode proteins, HSP-90 and ODR1, supporting their potential nematicidal mechanism. This research highlights the effectiveness of neem leaf extract-mediated ZnO nanostructures as an eco-friendly, sustainable alternative for nematode control, presenting a promising solution for agricultural pest management. Full article
(This article belongs to the Special Issue (Bio)nanomaterials in Catalysis)
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13 pages, 2374 KiB  
Article
Interaction Between Bovine Serum Albumin and Trans-Resveratrol: Multispectroscopic Approaches and Molecular Dynamics Simulation
by Xiujuan Li, Mimi Guo, Chenxia Xie, Yalin Xue, Junhui Zhang, Dong Zhang and Zhangqun Duan
Foods 2025, 14(14), 2536; https://doi.org/10.3390/foods14142536 - 20 Jul 2025
Viewed by 295
Abstract
Recent studies have increasingly focused on molecular interactions between small molecules and proteins, especially binding mechanisms and thermodynamics, using multispectroscopic and molecular dynamics approaches. This study elucidated the molecular interaction mechanism between bovine serum albumin (BSA) and trans-resveratrol (Res) through an integrated [...] Read more.
Recent studies have increasingly focused on molecular interactions between small molecules and proteins, especially binding mechanisms and thermodynamics, using multispectroscopic and molecular dynamics approaches. This study elucidated the molecular interaction mechanism between bovine serum albumin (BSA) and trans-resveratrol (Res) through an integrated approach combining multispectroscopic analyses and molecular dynamics simulations. The fluorescence quenching study revealed a static quenching mechanism between BSA and Res, which was further confirmed via ultraviolet–visible (UV-Vis) absorption spectroscopy. In particular, KSV decreased from 5.01 × 104 M−1 at 298 K to 3.99 × 104 M−1 at 318 K. Furthermore, the calculated Kq values significantly exceeded 1 × 1012 M−1 s−1. With increasing Res concentration, the peak fluorescence intensities of Tyr and Trp residues both exhibited a blue shift. The α-helix content of the BSA–Res complex was 59.8%, slightly lower than that of BSA (61.3%). Res was found to bind to site I in subdomain IIA of BSA. The molecular dynamics simulation also identified the specific binding of Res to site I of BSA, while thermodynamic studies revealed that the binding process occurs spontaneously and is primarily mediated by hydrogen bonding interactions. These findings not only enrich the theoretical framework of small-molecule–protein interactions but also provide a crucial scientific foundation for the development and utilization of natural products. Full article
(This article belongs to the Section Food Analytical Methods)
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18 pages, 11678 KiB  
Article
Inclusions, Chemical Composition, and Spectral Characteristics of Pinkish-Purple to Purple Spinels from Mogok, Myanmar
by Danyu Guo, Geng Li, Liqun Weng, Meilun Zhang and Fabian Dietmar Schmitz
Crystals 2025, 15(7), 659; https://doi.org/10.3390/cryst15070659 - 19 Jul 2025
Viewed by 213
Abstract
With the increasing market demand for spinels of various colors, purple spinel—long regarded as a symbol of nobility—has attracted growing attention. In this study, pinkish-purple to purple spinels from the Mogok region of Myanmar were systematically examined using conventional gemological, spectroscopic, and chemical [...] Read more.
With the increasing market demand for spinels of various colors, purple spinel—long regarded as a symbol of nobility—has attracted growing attention. In this study, pinkish-purple to purple spinels from the Mogok region of Myanmar were systematically examined using conventional gemological, spectroscopic, and chemical analytical techniques. Raman analysis reveals that these spinels commonly contain octahedral inclusions composed of calcite, dolomite, magnesite, and graphite. Chemically, the samples are primarily magnesia-alumina spinels. Color variation is influenced by trace elements: increasing Cr and V contents enhance the red hue, while higher Fe concentrations intensify the purple tone. UV–Vis spectra show that Cr3+ and V3+ jointly contribute to absorptions at 388 nm and 548 nm, with Fe2+ and Fe3+ responsible for the bands at 371 nm and 457 nm, respectively, together controlling the pink-to-purple color variation. Most samples display four Cr3+-related peaks near 700 nm; however, these are absent in deeply purple spinels. In contrast, light pink spinels show weaker absorption at 371 nm and 457 nm, attributed to Fe2+ and Fe3+. Fluorescence spectra confirm characteristic Cr3+ emission bands at 673 nm, 684 nm, 696 nm, 706 nm, and 716 nm, indicating a strong crystal field environment. Raman spectra have peaks mainly around 312 cm−1, 406 cm−1, 665 cm−1, and 768 cm−1. The peaks of the infrared spectrum mainly appear around 840 cm−1, 729 cm−1, 587 cm−1, 545 cm−1, and 473 cm−1. Full article
(This article belongs to the Collection Topic Collection: Mineralogical Crystallography)
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16 pages, 4479 KiB  
Article
Photophysical Properties of 1,3-Diphenylisobenzofuran as a Sensitizer and Its Reaction with O2
by Ștefan Stan, João P. Prates Ramalho, Alexandru Holca and Vasile Chiș
Molecules 2025, 30(14), 3021; https://doi.org/10.3390/molecules30143021 - 18 Jul 2025
Viewed by 352
Abstract
1,3-Diphenylisobenzofuran (DPBF) is a widely used fluorescent probe for singlet oxygen (1O2) detection in photodynamic applications. In this work, we present an integrated experimental and computational analysis to describe its spectroscopic, photophysical, and reactive properties in ethanol, DMSO, and [...] Read more.
1,3-Diphenylisobenzofuran (DPBF) is a widely used fluorescent probe for singlet oxygen (1O2) detection in photodynamic applications. In this work, we present an integrated experimental and computational analysis to describe its spectroscopic, photophysical, and reactive properties in ethanol, DMSO, and DMF. UV-Vis and fluorescence measurements across a wide concentration range show well-resolved S0 → S1 electronic transition of a π → π* nature with small red shifts in polar aprotic solvents. Fluorescence lifetimes increase slightly with solvent polarity, showing stabilization of the excited state. The 2D PES and Boltzmann populations analysis indicate two co-existing conformers (Cs and C2), with Cs being slightly more stable at room temperature. TD-DFT calculations have been performed using several density functionals and the 6-311+G(2d,p) basis set to calculate absorption/emission wavelengths, oscillator strengths, transition dipole moments, and radiative lifetimes. Overall, cam-B3LYP and ωB97X-D provided the best agreement with experiments for the photophysical data across all solvents. The photophysical behavior of DPBF upon interaction with 1O2 can be explained by a small-barrier, two-step reaction pathway that goes through a zwitterionic intermediate, resulting in the formation of 2,5-endoperoxide. This work explains the photophysical properties and reactivity of DPBF, therefore providing a solid basis for future studies involving singlet oxygen. Full article
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19 pages, 1855 KiB  
Article
Enhanced Antimicrobial Activity of Green-Synthesized Artemisia-ZnO Nanoparticles: A Comparative Study with Pure ZnO Nanoparticles and Plant Extract
by Noor Akhras, Abuzer Çelekli and Hüseyin Bozkurt
Foods 2025, 14(14), 2449; https://doi.org/10.3390/foods14142449 - 11 Jul 2025
Viewed by 646
Abstract
The green synthesis of zinc oxide nanoparticles (ZnO NPs) using Artemisia absinthium L. extract has gained considerable attention due to its eco-friendly approach and potential applications in food science. This study investigates the synthesis and characterization of Artemisia-mediated ZnO NPs, focusing on [...] Read more.
The green synthesis of zinc oxide nanoparticles (ZnO NPs) using Artemisia absinthium L. extract has gained considerable attention due to its eco-friendly approach and potential applications in food science. This study investigates the synthesis and characterization of Artemisia-mediated ZnO NPs, focusing on their physicochemical properties. The nanoparticles were characterized using ultraviolet–visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), and energy dispersive X-ray spectroscopy (EDX). Successful synthesis was achieved through a co-precipitation method, resulting in an average particle size of 36.6 nm. The presence of polyphenols and flavonoids in A. absinthium L. extract acted as both a reducing agent and stabilizer for the nanoparticles. The physicochemical characterization revealed strong absorption peaks indicative of ZnO, confirming successful nanoparticle formation. In addition to the structural findings, this study presents novel insights by demonstrating that Artemisia-mediated ZnO NPs possess significantly enhanced antimicrobial activity compared to both pure ZnO NPs and the plant extract alone. The biosynthesized nanoparticles exhibited notably lower minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC) values against Staphylococcus aureus, Escherichia coli, and Candida albicans, suggesting a strong synergistic effect between ZnO and the phytochemicals of A. absinthium L. Thus, the study confirms and quantifies the superior antibacterial potential of Artemisia-derived ZnO NPs, offering promising implications for food, biomedical and pharmaceutical applications. Full article
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17 pages, 4195 KiB  
Article
Rapid Synthesis of Highly Crystalline ZnO Nanostructures: Comparative Evaluation of Two Alternative Routes
by Emely V. Ruiz-Duarte, Juan P. Molina-Jiménez, Duber A. Avila, Cesar O. Torres and Sindi D. Horta-Piñeres
Crystals 2025, 15(7), 640; https://doi.org/10.3390/cryst15070640 - 11 Jul 2025
Viewed by 291
Abstract
Zinc oxide (ZnO) is a wide bandgap semiconductor of great scientific and technological interest due to its high exciton binding energy and outstanding structural and optical properties, making it an ideal material for applications in optoelectronics, sensors, and photocatalysis. This study presents the [...] Read more.
Zinc oxide (ZnO) is a wide bandgap semiconductor of great scientific and technological interest due to its high exciton binding energy and outstanding structural and optical properties, making it an ideal material for applications in optoelectronics, sensors, and photocatalysis. This study presents the rapid synthesis of highly crystalline ZnO nanostructures using two alternative routes: (1) direct thermal decomposition of zinc acetate and (2) a physical-green route assisted by Mangifera indica extract. Both routes were subjected to identical calcination thermal conditions (400 °C for 2 h), allowing for an objective comparison of their effects on structural, vibrational, morphological, and optical characteristics. X-ray diffraction analyses confirmed the formation of a pure hexagonal wurtzite phase in both samples, highlighting a higher crystallinity index (91.6%) and a larger crystallite size (35 nm) in the sample synthesized using the physical-green route. Raman and FTIR spectra supported these findings, revealing greater structural order. Electron microscopy showed significant morphological differences, and UV-Vis analysis showed a red shift in the absorption peak, associated with a decrease in the optical bandgap (from 3.34 eV to 2.97 eV). These results demonstrate that the physical-green route promotes significant improvements in the structural and functional properties of ZnO, without requiring changes in processing temperature or the use of additional chemicals. Full article
(This article belongs to the Special Issue Synthesis and Characterization of Oxide Nanoparticles)
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27 pages, 4704 KiB  
Article
Chemical Composition and Corrosion—Contributions to a Sustainable Use of Geothermal Water
by Ioana Maior, Gabriela Elena Badea, Oana Delia Stănășel, Mioara Sebeșan, Anca Cojocaru, Anda Ioana Graţiela Petrehele, Petru Creț and Cristian Felix Blidar
Energies 2025, 18(14), 3634; https://doi.org/10.3390/en18143634 - 9 Jul 2025
Viewed by 332
Abstract
The utilization of geothermal resources as renewable energy is a subject of interest for the regions that possess these resources. The exploitation of geothermal energy must consider local geological conditions and an integrated approach, which should include practical studies on the chemistry of [...] Read more.
The utilization of geothermal resources as renewable energy is a subject of interest for the regions that possess these resources. The exploitation of geothermal energy must consider local geological conditions and an integrated approach, which should include practical studies on the chemistry of geothermal waters and their effect on thermal installations. Geothermal waters from Bihor County, Romania, have a variable composition, depending on the crossed geological layers, but also on pressure and temperature. Obviously, water transport and heat transfer are involved in all applications of geothermal waters. This article aims to characterize certain geothermal waters from the point of view of composition and corrosion if used as a thermal agent. Atomic absorption spectroscopy (AAS) and UV–Vis spectroscopy were employed to analyze water specimens. Chemical composition includes calcite (CaCO3), chalcedony (SiO2), goethite (FeO(OH)), and magnetite (Fe3O4), which confirms the corrosion and scale potential of these waters. Corrosion resistance of mild carbon steel, commonly used as pipe material, was studied by the gravimetric method and through electrochemical methodologies, including chronoamperometry, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization method, and open circuit potential measurement (OCP). Statistical analysis shows that the medium corrosion rate of S235 steel, expressed as penetration rate, is between 0.136 mm/year to 0.615 mm/year. The OCP, EIS, and chronoamperometry experiments explain corrosion resistance through the formation of a passive layer on the surface of the metal. This study proposes an innovative methodology and a systematic algorithm for analyzing chemical processes and corrosion phenomena in geothermal installations, emphasizing the necessity of individualized assessments for each aquifer to optimize operational parameters and ensure sustainable resource utilization. Full article
(This article belongs to the Special Issue The Status and Development Trend of Geothermal Resources)
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14 pages, 2265 KiB  
Article
Octahedral Paclobutrazol–Zinc Complex for Enhanced Chemical Topping Efficacy in Mechanized Cotton Production: A Two-Year Field Evaluation in Xinjiang
by Jincheng Shen, Sumei Wan, Guodong Chen, Jianwei Zhang, Chen Liu, Junke Wu, Yong Li, Jie Liu, Shuren Liu, Baojiu Zhang, Meng Lu and Hongqiang Dong
Agronomy 2025, 15(7), 1659; https://doi.org/10.3390/agronomy15071659 - 8 Jul 2025
Viewed by 491
Abstract
Topping is an essential step in cotton cultivation in Xinjiang, China, which can effectively increase the number of bolls per plant and optimize the yield and quality. Paclobutrazol, as a common chemical topping agent for cotton, faces challenges such as unstable topping effect [...] Read more.
Topping is an essential step in cotton cultivation in Xinjiang, China, which can effectively increase the number of bolls per plant and optimize the yield and quality. Paclobutrazol, as a common chemical topping agent for cotton, faces challenges such as unstable topping effect and limited leaf surface absorption during application. In this study, paclobutrazol was used as the ligand and a zinc complex was synthesized by the thermosolvent method to replace paclobutrazol and improve the topping effect on cotton. The structure of the complex was characterized using FTIR, UV-vis, TG, and XRD analyses. The results confirmed that each zinc ion coordinated with four nitrogen atoms from the triazole rings of paclobutrazol and two oxygen atoms from nitrate ions, forming an octahedral geometry. Surface tension measurement and analysis revealed that the complex had a surface tension reduction of 12.75 mN/m compared to paclobutrazol, thereby enhancing the surface activity of the complex in water systems and improving its absorption efficiency on plant leaves. Two-year field trials indicated that the foliar application of the complex at a dosage of 120 g·hm−2 in inhibiting cotton plant height was more stable to that of paclobutrazol or mepiquat chloride. It also shortened the length of fruiting branches, making the shape of cotton plants compact, thereby indirectly improving the ventilation and light penetration of the cotton field and the convenience of mechanical harvesting. Yield data showed that, compared with artificial topping, the complex at a dosage of 120 g·hm−2 treatment increased cotton yield by approximately 4.6%. Therefore, the paclobutrazol–zinc complex is a promising alternative to manual topping and have great application potential in future mechanized cotton production. Full article
(This article belongs to the Section Farming Sustainability)
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19 pages, 2086 KiB  
Article
Strategic Doping for Precise Structural Control and Intense Photocurrents Under Visible Light in Ba2M0.4Bi1.6O6 (M = La, Ce, Pr, Pb, Y) Double Perovskites
by Tirong Guo, Wen Tian Fu and Huub J. M. de Groot
Nanomaterials 2025, 15(13), 1039; https://doi.org/10.3390/nano15131039 - 4 Jul 2025
Viewed by 334
Abstract
Developing functional perovskites is important for advancing solar energy conversion technologies. This study investigates the effects of dopants on the structural, optical, electronic, and solar conversion performances of Ba2M0.4Bi1.6O6 double perovskites. X-ray diffraction (XRD) and Rietveld [...] Read more.
Developing functional perovskites is important for advancing solar energy conversion technologies. This study investigates the effects of dopants on the structural, optical, electronic, and solar conversion performances of Ba2M0.4Bi1.6O6 double perovskites. X-ray diffraction (XRD) and Rietveld refinement confirm crystallization in the I2/m space group (M = La, Ce, Pr, Pb), and Fm3¯m and I2/m space groups (M = Y). The B1-O-B2 structure modulates to highly ordered (M = La, Y), partially ordered (M = Pr), or disordered (M = Ce, Pb). UV-vis spectra show strong light absorption, with Tauc plots estimating ~1.57 eV (M = La) and ~1.73 eV (M = Pr) optical band gaps. Under AM 1.5G illumination, the M = La photoelectrode generates photocurrents of 1 mA cm−2 at 0.3 VRHE, surpassing M = Ce and Pb (1 μm, 4-times spin-coating). Increasing its thickness to 7.7 μm (4-times dip-coating) further enhances the photocurrents to 2.3 mA cm−2 at 0.2 VRHE, outperforming all counterparts due to improved stability. Fine-tuning crystal and electronic structures via strategic B-site doping provides a new route for engineering Ba2Bi2O6-based double perovskites for broad solar energy conversion applications. Full article
(This article belongs to the Special Issue Organic/Perovskite Solar Cell)
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17 pages, 1034 KiB  
Article
Monitoring of Vitamin C Plasma Levels in a Reversible Model of Malabsorption Generated in Mice by Ebulin-f
by Daniel Arranz-Paraiso, M. Angeles Rojo, Cristina Martin-Sabroso, Manuel Cordoba-Diaz, Tomás Girbés, Manuel Garrosa and Damian Cordoba-Diaz
Toxins 2025, 17(7), 333; https://doi.org/10.3390/toxins17070333 - 30 Jun 2025
Viewed by 589
Abstract
The development of reversible animal models for the study of intestinal pathologies is essential to reduce the number of animals used in research and to better understand disease mechanisms. In this study, we present a reversible model of intestinal malabsorption through the administration [...] Read more.
The development of reversible animal models for the study of intestinal pathologies is essential to reduce the number of animals used in research and to better understand disease mechanisms. In this study, we present a reversible model of intestinal malabsorption through the administration of sublethal doses of ebulin-f, a ribosome-inactivating protein, and validate its usefulness by monitoring vitamin C absorption. The scientific community increasingly recognizes the importance of rationalizing experimental designs, optimizing treatment protocols, and minimizing the use of animals in research models. Thus, new methodologies are needed to minimize invasive sampling and to develop reversible animal models that recover physiologically post-study. Such models are essential for in vivo studies of human pathologies. Sublethal doses of ebulin-f (2.5 mg/kg) administered intraperitoneally to female Swiss CD1 mice (n = 6 per group) can cause reversible intestinal alterations in the small intestine, which offer the possibility of having a valuable reversible study model of malabsorption for the investigation of this syndrome. To verify whether nutrient absorption is altered, we used vitamin C as a traceable nutrient that can be quantified in the blood. Peripheral blood samples were collected through the retro-orbital area at 30, 80, 120, 180, and 1440 min post-administration, treated with DTT and MPA, and analyzed using a validated UV/Vis–HPLC method to indirectly determine vitamin C absorption by enterocytes. Pharmacokinetic analysis revealed significantly increased vitamin C absorption on days 1 and 3 post-treatment (AUC values of 3.65 × 104 and 7.10 × 104, respectively) compared to control (0.94 × 104), with partial recovery by day 22 (3.27 × 104). Blood concentration profiles indicate that intestinal damage peaks at day 3, followed by significant regeneration by day 22, establishing this as a viable reversible model for inflammatory bowel disease research. Full article
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18 pages, 2460 KiB  
Article
Extracellular Synthesis of Bioactive Silver Nanoparticles Using Brevibacillus sp. MAHUQ-41 and Their Potential Application Against Drug-Resistant Bacterial Pathogens Listeria monocytogenes and Yersinia enterocolitica
by Md. Amdadul Huq
J. Funct. Biomater. 2025, 16(7), 241; https://doi.org/10.3390/jfb16070241 - 30 Jun 2025
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Abstract
The purpose of current study was the green synthesis of bioactive silver nanoparticles (AgNPs) using Brevibacillus sp. MAHUQ-41 and the exploration of their role in controlling drug-resistant bacterial pathogens Listeria monocytogenes and Yersinia enterocolitica. The culture supernatant of strain MAHUQ-41 was employed [...] Read more.
The purpose of current study was the green synthesis of bioactive silver nanoparticles (AgNPs) using Brevibacillus sp. MAHUQ-41 and the exploration of their role in controlling drug-resistant bacterial pathogens Listeria monocytogenes and Yersinia enterocolitica. The culture supernatant of strain MAHUQ-41 was employed for a simple and eco-friendly synthesis of biofunctional silver nanoparticles (AgNPs). The resulting nanoparticles were analyzed using several techniques, including UV–Visible spectroscopy, XRD, FE-TEM, FTIR, and DLS. The UV–Vis spectral analysis of the AgNPs synthesized via Brevibacillus sp. MAHUQ-41 revealed a prominent absorption peak at 400 nm. FE-TEM results confirmed spherical-shaped 15–60 nm sized nanoparticles. XRD results indicated that the synthesized AgNPs were crystalline in nature. The FTIR spectrum determined various functional groups on the surface of synthesized nanoparticles. Potent antibacterial properties were observed in green-synthesized AgNPs against tested pathogens. The MIC value of extracellular synthesized AgNPs for both pathogenic bacteria was 6.2 µg/mL, and the MBCs were 25.0 µg/mL and 12.5 µg/mL for L. monocytogenes and Y. enterocolitica, respectively. Treatment by synthesized AgNPs resulted in morphological alterations and structural damages in both L. monocytogenes and Y. enterocolitica. These alterations can interfere with regular cellular activities, potentially resulting in cell death. This study is the first to report the antimicrobial properties of silver nanoparticles synthesized using Brevibacillus sp. MAHUQ-41. The findings obtained in the present study supported the role of Brevibacillus sp. MAHUQ-41-mediated synthesized AgNPs in controlling drug-resistant bacterial pathogens L. monocytogenes and Y. enterocolitica. Full article
(This article belongs to the Special Issue Antimicrobial Biomaterials for Medical Applications)
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