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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124988, 2025 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-39163772

RESUMEN

Two quinoxaline dyes utilized in copper-electrolyte-based dye-sensitized solar cells (Cu-DSSCs) are theoretically investigated to analyze the impact of alkyl chains on dye performance. The investigation shows that ZS4, known for its record efficiency of up to 13.2 %, exhibits higher electron coupling and fewer binding sites for dye-[Cu(tmby)2]2+ interaction compared to ZS5. Contrary to common belief, alkyl chains are found to not only provide shielding but also hinder the interaction between dye and [Cu(tmby)2]2+ by influencing the optimal conformation of dyes, thereby impeding the charge recombination process. It is crucial to consider the influence of alkyl chains on dye conformation when discussing the relationship between dye structure and performance, rather than oversimplifying it as often done traditionally. Building on these findings, eight dyes are strategically designed by adjusting the position of the alkyl chain to further decrease charge recombination compared to ZS4. Theoretical evaluation of these dyes reveals that changing the alkyl chain on the nitrogen atom from 2-ethylhexyl (ZS4) to 1-hexylheptyl (D3-2) not only reduces the charge recombination rate but also enhances light harvesting ability. Therefore, D3-2 shows potential as a candidate for experimental synthesis of high-performance Cu-DSSCs with improved efficiency.

2.
J Environ Sci (China) ; 148: 476-488, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39095182

RESUMEN

In this study, non-thermal plasma (NTP) was employed to modify the Cu/TiO2 adsorbent to efficiently purify H2S in low-temperature and micro-oxygen environments. The effects of Cu loading amounts and atmospheres of NTP treatment on the adsorption-oxidation performance of the adsorbents were investigated. The NTP modification successfully boosted the H2S removal capacity to varying degrees, and the optimized adsorbent treated by air plasma (Cu/TiO2-Air) attained the best H2S breakthrough capacity of 113.29 mg H2S/gadsorbent, which was almost 5 times higher than that of the adsorbent without NTP modification. Further studies demonstrated that the superior performance of Cu/TiO2-Air was attributed to increased mesoporous volume, more exposure of active sites (CuO) and functional groups (amino groups and hydroxyl groups), enhanced Ti-O-Cu interaction, and the favorable ratio of active oxygen species. Additionally, the X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results indicated the main reason for the deactivation was the consumption of the active components (CuO) and the agglomeration of reaction products (CuS and SO42-) occupying the active sites on the surface and the inner pores of the adsorbents.


Asunto(s)
Cobre , Sulfuro de Hidrógeno , Oxidación-Reducción , Titanio , Titanio/química , Adsorción , Cobre/química , Sulfuro de Hidrógeno/química , Contaminantes Atmosféricos/química , Gases em Plasma/química , Modelos Químicos
3.
J Environ Sci (China) ; 149: 476-487, 2025 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-39181660

RESUMEN

Herein, three supported catalysts, CuO/Al2O3, CeO2/Al2O3, and CuO-CeO2/Al2O3, were synthesized by the convenient impregnation method to reveal the effect of CeO2 addition on catalytic performance and reaction mechanism for toluene oxidation. Compared with CuO/Al2O3, the T50 and T90 (the temperatures at 50% and 90% toluene conversion, respectively) of CuO-CeO2/Al2O3 were reduced by 33 and 39 °C, respectively. N2 adsorption-desorption experiment, XRD, SEM, EDS mapping, Raman, EPR, H2-TPR, O2-TPD, XPS, NH3-TPD, Toluene-TPD, and in-situ DRIFTS were conducted to characterize these catalysts. The excellent catalytic performance of CuO-CeO2/Al2O3 could be attributed to its strong copper-cerium interaction and high oxygen vacancies concentration. Moreover, in-situ DRIFTS proved that CuO-CeO2/Al2O3 promoted the conversion of toluene to benzoate and accelerated the deep degradation path of toluene. This work provided valuable insights into the development of efficient and economical catalysts for volatile organic compounds.


Asunto(s)
Cerio , Cobre , Oxidación-Reducción , Tolueno , Tolueno/química , Catálisis , Cobre/química , Cerio/química , Modelos Químicos , Contaminantes Atmosféricos/química
4.
Biomaterials ; 313: 122805, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39250865

RESUMEN

Copper (Cu), an essential micronutrient with redox properties, plays a pivotal role in a wide array of pathological and physiological processes across virtually all cell types. Maintaining an optimal copper concentration is critical for cellular survival: insufficient copper levels disrupt respiration and metabolism, while excess copper compromises cell viability, potentially leading to cell death. Similarly, in the context of cancer, copper exhibits a dual role: appropriate amount of copper can promote tumor progression and be an accomplice, yet beyond befitting level, copper can bring about multiple types of cell death, including autophagy, apoptosis, ferroptosis, immunogenic cell death, pyroptosis, and cuproptosis. These forms of cell death are beneficial against cancer progression; however, achieving precise copper regulation within tumors remains a significant challenge in the pursuit of effective cancer therapies. The emergence of nanodrug delivery systems, distinguished by their precise targeting, controlled release, high payload capacity, and the ability to co-deliver multiple agents, has revitalized interest in exploiting copper's precise regulatory capabilities. Nevertheless, there remains a dearth of comprehensive review of copper's bidirectional effects on tumorigenesis and the role of copper-based nanomaterials in modulating tumor progression. This paper aims to address this gap by elucidating the complex role in cancer biology and highlighting its potential as a therapeutic target. Through an exploration of copper's dualistic nature and the application of nanotechnology, this review seeks to offer novel insights and guide future research in advancing cancer treatment.


Asunto(s)
Cobre , Nanoestructuras , Neoplasias , Cobre/química , Humanos , Animales , Nanoestructuras/química , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Neoplasias/metabolismo , Muerte Celular/efectos de los fármacos
5.
Biomaterials ; 312: 122720, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39084098

RESUMEN

Mesenchymal stem cells (MSCs) are expected to be useful therapeutics in osteoarthritis (OA), the most common joint disorder characterized by cartilage degradation. However, evidence is limited with regard to cartilage repair in clinical trials because of the uncontrolled differentiation and weak cartilage-targeting ability of MSCs after injection. To overcome these drawbacks, here we synthesized CuO@MSN nanoparticles (NPs) to deliver Sox9 plasmid DNA (favoring chondrogenesis) and recombinant protein Bmp7 (inhibiting hypertrophy). After taking up CuO@MSN/Sox9/Bmp7 (CSB NPs), the expressions of chondrogenic markers were enhanced while hypertrophic markers were decreased in response to these CSB-engineered MSCs. Moreover, a cartilage-targeted peptide (designated as peptide W) was conjugated onto the surface of MSCs via a click chemistry reaction, thereby prolonging the residence time of MSCs in both the knee joint cavity of mice and human-derived cartilage. In a surgery-induced OA mouse model, the NP and peptide dual-modified W-CSB-MSCs showed an enhancing therapeutic effect on cartilage repair in knee joints compared with other engineered MSCs after intra-articular injection. Most importantly, W-CSB-MSCs accelerated cartilage regeneration in damaged cartilage explants derived from OA patients. Thus, this new peptide and NPs dual engineering strategy shows potential for clinical applications to boost cartilage repair in OA using MSC therapy.


Asunto(s)
Diferenciación Celular , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Nanopartículas , Osteoartritis , Péptidos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Animales , Osteoartritis/terapia , Osteoartritis/patología , Nanopartículas/química , Humanos , Diferenciación Celular/efectos de los fármacos , Péptidos/química , Trasplante de Células Madre Mesenquimatosas/métodos , Condrogénesis/efectos de los fármacos , Ratones , Factor de Transcripción SOX9/metabolismo , Factor de Transcripción SOX9/genética , Cartílago Articular/patología , Cartílago Articular/efectos de los fármacos , Proteína Morfogenética Ósea 7/química , Proteína Morfogenética Ósea 7/farmacología , Ingeniería de Tejidos/métodos , Regeneración/efectos de los fármacos
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 125008, 2025 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-39182400

RESUMEN

N-acetyl-L-cysteine (NAC) as a class of thiols is commonly used in the treatment of lung diseases, detoxification and prevention of liver damage. In this paper, 4-mercaptobenzoic acid (4-MBA) coated and polyvinylpyrrolidone (PVP) attached copper nanoclusters (4-MBA@PVP-CuNCs) were successfully synthesized using a simple one-pot method with an absolute quantum yield of 10.98 %, and its synthetic conditions (like effects of single/double ligands and temperature) were studied intensively. Then Hg2+ could quench the fluorescence of the 4-MBA@PVP-CuNCs and its fluorescence was restored with the addition of NAC. Based on the above principles, an off-on switching system was established to detect NAC. That is, the 4-MBA@PVP-CuNCs-Hg probe was prepared by adding Hg2+ to switch off the fluorescence of the CuNCs by static quenching, and then NAC was added to switch on the fluorescence of the probe based on the chelation of NAC and Hg2+. Moreover, the effects of metal ion types and mercury ion doses for the probe construction were also further discussed. The method showed excellent linearity in the range of 0.05-1.25 µM and low detection limit of 16 nM. Meanwhile, good recoveries in real urine, tablets and pellets were observed, which proved the reliability of the method and provided a convenient, fast and sensitive method for NAC detection.


Asunto(s)
Acetilcisteína , Cobre , Límite de Detección , Nanopartículas del Metal , Espectrometría de Fluorescencia , Compuestos de Sulfhidrilo , Acetilcisteína/química , Acetilcisteína/orina , Cobre/química , Cobre/análisis , Espectrometría de Fluorescencia/métodos , Compuestos de Sulfhidrilo/química , Compuestos de Sulfhidrilo/análisis , Ligandos , Nanopartículas del Metal/química , Mercurio/análisis , Mercurio/orina , Humanos , Colorantes Fluorescentes/química , Povidona/química , Benzoatos/química , Polímeros/química
7.
Chemosphere ; 365: 143328, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39271076

RESUMEN

This study presents an innovative approach to eco-friendly synthesis and utilization of copper nanoparticles (CuNPs) for photocatalytic applications, employing waste corn husk fibers as sustainable catalyst support. The synthesis of CuNPs was achieved through a green synthesis method utilizing myrtle extract. Subsequently, the remarkable photocatalytic activity of the CuNPs explored (76% removal efficiency of Crystal Violet), showcased their potential in environmental remediation applications. Furthermore, the immobilization of CuNPs onto waste corn husk fibers was investigated, aiming to develop a novel composite material with enhanced catalytic performance. A distinctive approach was introduced by immobilizing CuNPs onto fibers derived from corn husks, and waste biomass material, leading to a significant enhancement in photocatalytic efficiency, surpassing 95.1%. Furthermore, bioactivity evaluation studies revealed the significant antioxidant, antidiabetic, DNA fragmentation, cell viability, antibiofilm and antimicrobial properties of CuNPs. The antioxidant ability was determined at 100 mg/L as 87.12%. The most powerful antimicrobial activity of CuNP was found as a MIC value of 8 mg/L against E. faecalis. The cell viability inhibition of CuNP was 90.05% at 20 mg/L. CuNP exhibited biofilm inhibition activity at different concentrations. The antibiofilm ability was investigated against Staphylococcus aureus compared to Pseudomonas aureginosa. While the DNA cleavage activity of CuNP observed double-strand breaks at 50 and 100 mg, complete fragmentation occurred at 200 mg concentrations. The bioactivity of the synthesized CuNPs shed light on their potential biomedical applications. The synthesized CuNPs are characterized using various analytical techniques to elucidate their structural and morphological properties. Fourier-transform infrared (FTIR) analysis provided insights into the chemical composition and surface properties of the synthesized materials. EDS analysis confirmed their successful integration into waste corn husk fibers. Overall, this interdisciplinary study highlights the potential of CuNPs immobilized on waste corn husk fibers for addressing environmental pollution, advancing sustainable technologies and paving the way for the development of efficient catalysts with diverse functionalities.

8.
Toxicon ; 250: 108103, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39278473

RESUMEN

Thymoquinone is the main active compound derived from the essential oil of the Nigella sativa plant seed. While thymoquinone is an antioxidant, it has been reported in several studies that thymoquinone has dose-dependent pro-oxidant activity with the Fenton reaction in the presence of transition elements such as iron and copper. This study aimed to investigate cytotoxic, apoptotic, genotoxic, and reactive oxygen species (ROS) generating effects of thymoquinone treated with copper in colon cancer cells. HT-29 cells were treated with pro-oxidant-acting doses of thymoquinone alone and together with the non-toxic dose of Copper (II) Sulfate for 24 h. Cytotoxic, apoptotic, genotoxic, and ROS production activities were analyzed by MTT viability test, Acridine Orange/Ethidium Bromide (AO/EB) staining, alkaline single cell gel electrophoresis and H2DCF-DA assay, respectively. Viability results showed that thymoquinone and copper synergistically affect cancer cells, and DNA damage was increased with the synergic effect. The intracellular ROS was increased when thymoquinone and copper were applied together. Applying redox-active copper (II) with thymoquinone increases DNA damage, apoptosis, and cell death by increasing the amount of intracellular ROS through pro-oxidant activity. Treatments targeting copper-related pathways may open new therapeutic avenues for cancer treatment.

9.
Environ Pollut ; 362: 124956, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39278560

RESUMEN

The hard-shell mussels Mytilus coruscus have been extensively employed in pollution biomonitoring. Earlier studies indicated that metal concentrations in Mytilus coruscus may not accurately reflect the true metal contamination levels in the sampling areas, possibly due to their modified metal uptake and efflux. Given the likelihood of mussels in the field being exposed to intermittent metal contaminants, this study investigated whether different Cu pre-exposures significantly affected its uptake and efflux upon Cu exposure. We found significant reduction in Cu uptake rate constant (ku) and efflux rate constant (ke) in the mussels with varying Cu pre-exposure regimes. Specifically, the ku decreased from 1.55 ± 0.37 L g-1 d-1 in the control group to 0.65 ± 0.19 after 5 days and 0.53 ± 0.28 after 15 days of exposure to 20 µg L-1 Cu, respectively, and then was further reduced to as low as 0.096 ± 0.046 L g-1 d-1 following a 5-day exposure at 50 µg L-1 Cu. Similarly, the ke decreased from 0.18 ± 0.020 to 0.15 ± 0.015 d-1 following 5-15 days of exposure to 20 µg L-1 Cu, and further decreased to 0.081 ± 0.023 d-1 after a 5-day exposure at 50 µg L-1 Cu. Our subcellular distribution analysis underscored the critical role of the metallothionein-like protein (MTLP) fraction in modifying both Cu ku and ke during the rapid-depuration phase (ke1), whereas the metal-rich granule (MRG) fraction influenced the ke during the second depuration phase (ke2). This study demonstrated that environmental assessments utilizing biomonitoring species should consider the exposure of these organisms to ensure accurate interpretations of metal contamination in marine ecosystems and enhance the effectiveness of these species in environmental monitoring. This crucial factor is often overlooked, potentially skewing data and leading to misinterpretations of environmental health and pollution levels.

10.
Neuroimage ; 299: 120829, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39233127

RESUMEN

BACKGROUND: Quantitative susceptibility mapping (QSM) is a post-processing technique that creates brain susceptibility maps reflecting metal burden through tissue magnetic susceptibility. We assessed topographic differences in magnetic susceptibility between participants with and without Wilson's disease (WD), correlating these findings with clinical severity, brain volume, and biofluid copper and iron indices. METHODS: A total of 43 patients with WD and 20 unaffected controls, were recruited. QSM images were derived from a 3T MRI scanner. Clinical severity was defined using the minimal Unified Wilson's Disease Rating Scale (M-UWDRS) and Montreal Cognitive Assessment scoring. Differences in magnetic susceptibilities between groups were evaluated using general linear regression models, adjusting for age and sex. Correlations between the susceptibilities and clinical scores were analyzed using Spearman's method. RESULTS: In age- and sex-adjusted analyses, magnetic susceptibility values were increased in WD patients compared with controls, including caudate nucleus, putamen, globus pallidus, and substantia nigra (all p < 0.01). Putaminal susceptibility was greater with an initial neuropsychiatric presentation (n = 25) than with initial hepatic dysfunction (n = 18; p = 0.04). Susceptibility changes correlated negatively with regional brain volume in almost all topographic regions. Serum ferritin, but not serum copper or ceruloplasmin, correlated positively with magnetic susceptibility level in the caudate nucleus (p = 0.04), putamen (p = 0.04) and the hippocampus (p = 0.03). The dominance of magnetic susceptibility in cortical over subcortical regions correlated with M-UWDRS scores (p < 0.01). CONCLUSION: The magnetic susceptibility changes could serve as a surrogate marker for patients with WD.


Asunto(s)
Atrofia , Encéfalo , Cobre , Degeneración Hepatolenticular , Imagen por Resonancia Magnética , Humanos , Degeneración Hepatolenticular/patología , Degeneración Hepatolenticular/diagnóstico por imagen , Femenino , Masculino , Adulto , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Atrofia/patología , Cobre/sangre , Adulto Joven , Hierro/metabolismo , Hierro/sangre , Índice de Severidad de la Enfermedad , Adolescente , Persona de Mediana Edad
11.
J Hazard Mater ; 479: 135748, 2024 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-39243540

RESUMEN

A novel nitrate-dependent manganese (Mn) redox strain was isolated and identified as Dechloromonas sp.YZ8 in this study. The growth conditions of strain YZ8 were optimized by kinetic experiments. The nitrate (NO3--N) removal efficiency was 100.0 % at 16 h at C/N of 2.0, pH of 7.0, and Mn(II) or Mn(IV) addition of 10.0 or 500.0 mg L-1, along with an excellent Mn redox capacity. Transmission electron microscopy supported the Mn redox process inside and outside the cells of strain YZ8. When strain YZ8 was exposed to different concentrations of copper ion (Cu(II)), it turned out that moderate amounts of Cu(II) increased microbial activity and metabolic activities. Moreover, it was discovered that the appropriate amount of Cu(II) promoted the conversion of Mn(IV) and Mn(II) to Mn(III) and improved electron transfer capacity in the Mn redox system, especially the Mn redox process dominated by Mn(IV) reduction. Then, δ-MnO2 and bio-manganese oxides (BMO) produced during the reaction process have strong adsorption of Cu(II). The surface valence changes of δ-MnO2 before and after the reaction and the production of BMO, Mn(III)-rich intermediate black manganese ore (Mn3O4), and Mn secondary minerals together confirmed the Mn redox pathway. The study provided new insights into the promotion mechanism and immobilization effects of redox-coupled denitrification of Mn in groundwater under Cu(II) stress.


Asunto(s)
Cobre , Desnitrificación , Manganeso , Nitratos , Oxidación-Reducción , Cobre/química , Desnitrificación/efectos de los fármacos , Nitratos/metabolismo , Nitratos/química , Manganeso/química , Manganeso/metabolismo , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/química , Rhodocyclaceae/metabolismo , Biodegradación Ambiental
12.
J Inorg Biochem ; 261: 112721, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39236444

RESUMEN

Copper(II) complexes are very promising candidates for platinum-based anticancer agents. Herein, three Cu (II) complexes (1-3) containing 1,8-naphthalimide ligands were synthesized and characterized by FT-IR, elemental analysis, ESI-MS and single crystal X-ray diffraction (complex 3). In addition, a control compound (complex 4) without 1,8-naphthalimide ligand was synthesized and characterized. The in vitro anticancer activity of the synthesized complexes against five cancer cell lines and one normal cell line was evaluated by MTS assay. The results displayed the antitumor activity of complexes 1-3 was controlled by the aliphatic chain length of ligands, their cytotoxicity was in the order 3 > 2 > 1, giving the IC50 values ranging from 2.874 ± 0.155 µM to 31.47 ± 0.29 µM against five cancer cell lines. Complex 4 showed less activity in comparison with complex 1-3. Notably, complexes 1-3 displayed much higher selectivity (SI = 2.65 to 10.16) compared to complex 4 (SI = 1.0), indicated that the introduction of 1,8-naphthalimide group not only increased the activity of this series of compounds but also enhanced their specific selectivity to cancer cells. Compound 3 induced apoptosis in cancer cells and blocked the S-phase and G2/M of cancer cells. The interaction with DNA of complexes 3 and 4 was studied by UV/Vis spectroscopic titrations, competitive DNA-binding experiment, viscometry and CD spectra. The results showed that complex 3 interacted with DNA in an intercalating mode, but the interaction mode of compound 4 with DNA was electrostatic interaction.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Cobre , ADN , Naftalimidas , Humanos , Cobre/química , Naftalimidas/química , Naftalimidas/farmacología , Naftalimidas/síntesis química , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Complejos de Coordinación/farmacología , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , ADN/química , ADN/metabolismo , Ligandos , Línea Celular Tumoral , Apoptosis/efectos de los fármacos
13.
Sci Rep ; 14(1): 21024, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39251625

RESUMEN

A new conducting polymer of the cellulose acetate poly acrylonitrile (CAPA)-SiC composite was produced using an in situ oxidative polymerization technique in an aqueous medium. SiC was synthesized from Cinachyrella sp. as a source of carbon and silicon at 1200 °C under an argon atmosphere via a catalytic reduction process. The structure and morphology of the CAPA-SiC composite were characterized using surface area studies (BET), X-ray diffraction (XRD), Fourier transformation infrared spectroscopy (FT-IR), and surface morphology (SEM & TEM). To protect copper, the produced CAPA-SiC composite was mixed with commercial epoxy paint using a casting technique, and the copper surface was coated with the three components of the CAPA-SiC/epoxy paint mixture. The corrosion inhibition improvement of the CAPA-SiC/paint coating was assessed using electrochemical impedance spectroscopy followed by Tafel polarization measurements in a 3.5 wt% NaCl solution. The corrosion protection ability of the CAPA-SiC/epoxy coating was found to be outstanding at 97.4% when compared to that of a CAPA/paint coating. SEM and XRD were used to illustrate the coating on the copper surface.

14.
Waste Manag ; 189: 276-289, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39217802

RESUMEN

As one of the most widespread plastics in the world, the recycling of diethylhexyl phthalate-rich polyvinyl chloride (DEHP-rich PVC) faces great challenges because of the high levels of Cl and plasticizers. On the other hand, waste copper catalyst (WCC) discharged from various industrial processes is not effectively recycled. In this study, a significant synergistic effect between the DEHP-rich PVC and WCC was found in a subcritical water (SubCW) medium, and a co-treatment of the DEHP-rich PVC and WCC was developed by the SubCW process. The introduction of WCC significantly improved the dechlorination efficiency of the DEHP-rich PVC to 96.03 % at a low temperature of 250 °C. Under the optimal conditions, the leaching of copper from WCC reached a maximum of 81.08 %. Oil products included DEHP (55.7 %, GC peak area%), 3-methyl-3-heptene (37.3 %, GC peak area%), and 2-ethyl-1-hexanol (7.0 %, GC peak area%). The dechlorination pathways of the DEHP-rich PVC included hydroxyl substitution and direct dechlorination. HCl released from the DEHP-rich PVC led to a decrease in the pH of the system and significant copper leaching from the WCC. DEHP was decomposed by hydrolysis, dehydration, and rearrangement reaction by the SubCW co-treatment process. The enhancement mechanism of the WCC for the dechlorination of the DEHP-rich PVC was based on that the conversion of copper species in the SubCW promoted the formation of hydroxyl radicals and the hydroxyl substitution for chlorine in PVC molecular chain. The proposed SubCW low-temperature co-treatment could be a prospective strategy for the low-energy and synchronous recovery of the two different wastes of the DEHP-rich PVC and WCC.


Asunto(s)
Cobre , Dietilhexil Ftalato , Cloruro de Polivinilo , Cloruro de Polivinilo/química , Cobre/química , Dietilhexil Ftalato/química , Catálisis , Reciclaje/métodos , Temperatura , Agua/química , Halogenación
15.
Artículo en Inglés | MEDLINE | ID: mdl-39320964

RESUMEN

Terahertz absorbers play a crucial role in terahertz detectors, radar stealth, electromagnetic shielding, and other fields. However, the design and fabrication of flexible terahertz broadband absorbers remain a challenge at present. Here, we demonstrated a terahertz broadband absorber based on a copper composite film (CCF) consisting of a copper foam and an organic silica gel doped with Fe3O4 powder. The CCF can be fabricated by the infiltration method. The influence of the thickness and the pore size of the copper foam and the mass fraction of doped Fe3O4 powder on the absorption bandwidth were investigated. When the thickness of the CCF is 1.5 mm, the pore size of the copper foam is 95 pores per inch (ppi), and the mass fraction of Fe3O4 is 1%; a broadband absorption is achieved in the range of 0.11-3.5 THz. It is noted that the mass fraction of Fe3O4 has a significant impact on the absorption bandwidth. In addition, the thickness of the CCF and the pore size of the copper foam also have an impact on the absorption. The impedance matching theory is introduced to understand the mechanism of broadband absorption. This flexible broadband absorber has potential application in terahertz stealth, shielding, and the sixth-generation (6G) broadband wireless communication in the future.

16.
Angew Chem Int Ed Engl ; : e202414810, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39322938

RESUMEN

Developing ionic copper-iodine clusters with multiple emitting is crucial for enriching lighting and display materials with various colors. However, the luminescent properties of traditional ionic copper-iodine clusters are often closely associated with low-energy cluster-centered triplet emission, which will redshift further as the Cu···Cu bond length decreases. This article utilizes a pressure-treated strategy to achieve an anomalous pressure-induced blue-shifted luminescence phenomenon in ionic Cu4I6(4-dimethylamino-1-ethylpyridinium)2 crystals for the first time, which is based on dominant through-space charge-transfer (TSCT). Herein, we reveal that the more advantageous through-space interactions in the competition between coprophilic interactions and through-space interactions can lead to a blue-shifted luminescence. High-pressure angle-dispersive X-ray diffraction and high-pressure infrared experiments show that the enhanced through-space interactions mainly originate from forming new intermolecular C-H···I hydrogen bonds and the enhancement of van der Waals interactions between organic cations and anionic clusters. Theoretical calculations and experimental studies of excited-state dynamics confirm that the blue-shifted emission is due to the increased energy gap between the excited triplet and ground states caused by the electron delocalization under stronger through-space interactions. This work deepens previous understanding and provides a new avenue to design and synthetic ionic copper-iodine clusters with high-energy TSCT emission.

17.
Artículo en Inglés | MEDLINE | ID: mdl-39322981

RESUMEN

Nanozymes have been developed to overcome the inherent limitations of natural enzymes, such as their low stability and high cost. However, their efficacy has been hindered by their relatively low specificity and activity. Here, we demonstrate the self-assembly of individual copper nanoclusters (CuNCs) via a simple yet fast (10 min) DNA nanosheet (DNS)-templated method, enhancing the peroxidase-like activity and specificity of CuNCs. Furthermore, we demonstrate the successful assembly of CuNCs on different DNA nanostructures by atomic force microscopy (AFM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The resulting micron-scale ultrathin DNA nanosheet-templated CuNCs (DNS@CuNCs) exhibit exceptional catalytic activity, with a specific activity reaching 1.79 × 103 U mg-1. Investigation into the catalytic process reveals that the enhanced activity and specificity arise from disparities in active intermediate content before and after CuNCs assembly. Significantly, the DNS@CuNCs-based biosensor demonstrates remarkable anti-interference capabilities, enabling the detection of H2O2 in undiluted human serum for the first time with a detection limit of 0.99 µM.

18.
Heliyon ; 10(18): e37658, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39323846

RESUMEN

Directed energy deposition (DED) is a form of additive manufacturing available across a variety of laser spot diameter values, often referred to as spot sizes. However, there is no method to easily transfer process parameters across discrete spot sizes, leading to DED process parameters that are equipment specific and not widely applicable. In this study, a strategy is proposed and investigated for five spot sizes that keep the areal energy density constant while varying power, feed rate, and powder flow during the deposition of 316L stainless steel. An assessment of trends in hardness and microstructure is possible due to the novel production of components of a single material across several spot sizes using a single nozzle on a single DED system. The proposed strategy was used to nullify the hardness drop during functional grading of Inconel 625 and pure copper, enabling fabrication of multi-material sample that does not compromise desirable properties. This application shows the value in establishing more efficient process parameter development and understanding spot size influences on geometric and material property flexibility, to enable a more diverse powder-based DED design space and to increase the industry adoption of DED systems.

19.
mBio ; : e0219224, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39324795

RESUMEN

Tupanviruses, members of the family Mimiviridae, infect phagocytic cells. Particle uncoating begins inside the phagosome, with capsid opening via the stargate. The mechanism through which this opening takes place is unknown. Once phagocytized, metal ion flux control and ROS are induced to inactivate foreign particles, including viruses. Here, we studied the effect of iron ions, copper ions, and H2O2 on Tupanvirus particles. Such treatments induced stargate opening in vitro, as observed by different microscopy techniques. Metal-treated viruses were found to be non-infectious, leading to the hypothesis that stargate opening likely resulted in the release of the viral seed, which is required for infection initiation. To the best of our knowledge, this is the first description of a giant virus capsid morphological change induced by transition metals and H2O2, which may be important to describe new virulence factors and capsid uncoating mechanisms.

20.
Mini Rev Med Chem ; 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39328144

RESUMEN

Cuproptosis, An Emerging Concept In The Field Of Diabetes Research, Presents A Novel And Promising Perspective For The Effective Management Of Diabetes Mellitus And Its Associated Complications. Diabetes, Characterized By Chronic Hyperglycemia, Poses A Substantial Global Health Burden, With An Increasing Prevalence Worldwide. Despite Significant Progress In Our Understanding Of This Complex Metabolic Disorder, Optimal Therapeutic Strategies Still Remain Elusive. The Advent Of Cuproptosis, A Term Coined To Describe Copper-Induced Cellular Cell Death And Its Pivotal Role In Diabetes Pathogenesis, Opens New Avenues For Innovative Interventions. Copper, An Indispensable Trace Element, Plays A Pivotal Role In A Myriad Of Vital Biological Processes, Encompassing Energy Production, Bolstering Antioxidant Defenses, And Altered Cellular Signaling. However, In The Context Of Diabetes, This Copper Homeostasis Is Perturbed, Driven By A Combination Of Genetic Predisposition, Dietary Patterns, And Environmental Factors. Excessive Copper Levels Act As Catalysts For Oxidative Stress, Sparking Intricate Intracellular Signaling Cascades That Further Exacerbate Metabolic Dysfunction. In This Review, We Aim To Explore The Interrelationship Between Copper And Diabetes Comprehensively, Shedding Light On The Intricate Mechanisms Underpinning Cuproptosis. By Unraveling The Roles Of Copper Transporters, Copper-Dependent Enzymes, And Cuproptotic Signaling Pathways, We Seek To Elucidate Potential Therapeutic Strategies That Harness The Power Of Copper Modulation In Diabetes Management. This Insight Sets The Stage For A Targeted Approach To Challenge The Complex Hurdles Posed By Diabetes, Potentially Transforming Our Therapeutic Strategies In The Ongoing Fight Against This Pervasive Global Health Concern.

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