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ACS Applied Electronic Materials Jun 2024Flexible temperature sensors are becoming increasingly important these days. In this work, we explore graphene oxide (GO)/poly(vinyl alcohol) (PVA) nanocomposites for...
Flexible temperature sensors are becoming increasingly important these days. In this work, we explore graphene oxide (GO)/poly(vinyl alcohol) (PVA) nanocomposites for potential application in temperature sensors. The influence of the mixing ratio of both materials, the reduction temperature, and passivation on the sensing performance has been investigated. Various spectroscopic techniques revealed the composite structure and atomic composition. These were complemented by semiempirical quantum chemical calculations to investigate rGO and PVA interaction. Scanning electron and atomic force microscopy measurements were carried out to evaluate dispersion and coated film quality. The temperature sensitivity has been evaluated for several composite materials with different compositions in the range from 10 to 80 °C. The results show that a linear temperature behavior can be realized based on rGO/PVA composites with temperature coefficients of resistance (TCR) larger than 1.8% K and a fast response time of 0.3 s with minimal hysteresis. Furthermore, humidity influence has been investigated in the range from 10% to 80%, and a minor effect is shown. Therefore, we can conclude that rGO/PVA composites have a high potential for excellent passivation-free, humidity-independent, sensitive, and fast response temperature sensors for various applications. The GO reduction is tunable, and PVA improves the rGO/PVA sensor performance by increasing the tunneling effect and band gap energy, consequently improving temperature sensitivity. Additionally, PVA exhibits minimal water absorption, reducing the humidity sensitivity. rGO/PVA maintains its temperature sensitivity during and after several mechanical deformations.
PubMed: 38947952
DOI: 10.1021/acsaelm.4c00729 -
Frontiers in Oncology 2024Sirtuins are pivotal in orchestrating numerous cellular pathways, critically influencing cell metabolism, DNA repair, aging processes, and oxidative stress. In recent... (Review)
Review
Sirtuins are pivotal in orchestrating numerous cellular pathways, critically influencing cell metabolism, DNA repair, aging processes, and oxidative stress. In recent years, the involvement of sirtuins in tumor biology has garnered substantial attention, with a growing body of evidence underscoring their regulatory roles in various aberrant cellular processes within tumor environments. This article delves into the sirtuin family and its biological functions, shedding light on their dual roles-either as promoters or inhibitors-in various cancers including oral, breast, hepatocellular, lung, and gastric cancers. It further explores potential anti-tumor agents targeting sirtuins, unraveling the complex interplay between sirtuins, miRNAs, and chemotherapeutic drugs. The dual roles of sirtuins in cancer biology reflect the complexity of targeting these enzymes but also highlight the immense therapeutic potential. These advancements hold significant promise for enhancing clinical outcomes, marking a pivotal step forward in the ongoing battle against cancer.
PubMed: 38947884
DOI: 10.3389/fonc.2024.1384928 -
Sustainable Chemistry For the... Jun 2024Untreated tannery wastewater contains a large amount of toxic metals, dyes, and other pollutants, which pose adverse effects on the ecosystem and public health. In this...
Untreated tannery wastewater contains a large amount of toxic metals, dyes, and other pollutants, which pose adverse effects on the ecosystem and public health. In this work, a calcium alginate-poly vinyl alcohol-graphene oxide (CA-PVA-GO) composite was prepared to remove metals and dyes, particularly Cr(Ⅲ) and CI acid violet 54 (AV54) dye, from tannery wastewater. FESEM, FTIR, and XRD analyses were applied to characterize the GO and CA-PVA-GO. Different operational variables, viz. pH (3.0-5.5 for Cr(III) and 2-7 for dye), dosage (0.164-2.46 g/L), contact time (10-60 min), initial concentration (39, 65, 98, and 201 ppm for Cr(III) and 21.5, 38.5, 54.5, and 61.75 ppm for dye), and temperature (298, 308, 318, and 328 K) were studied to evaluate the efficiency of the CA-PVA-GO composite. The optimum conditions for Cr(Ⅲ) and AV54 dye adsorption were found to be pH (5.0 and 3.0), dosage (0.82 g/L for both), and time (45 and 60 min), respectively, with 35.35 ± 1.43% and 84.63 ± 2.54% removal efficiency. The experimental data was analyzed through the Langmuir and Freundlich isotherms. The maximum adsorption capacity (q) was observed at 173.01 and 74.68 mg/g for Cr(Ⅲ) and AV54 dye, respectively. The pseudo-second-order kinetic model was fitted better (R = 0.981, 0.995, 0.92, and 0.995) than first-order for AV54 dye adsorption. Thermodynamic analyses revealed that the Cr(Ⅲ) and AV54 dye adsorption processes were spontaneous and exothermic. The value of Gibbs free energy (ΔG) for Cr(III) adsorption was obtained at -7.433, -4.508, -2.626, and -1.311 kJ/mol, whereas it was -5.178, -4.867, -4.628, and -4.555 kJ/mol for dye. The values of ΔH and ΔS were -67.257 and -0.198 kJ/mol for Cr(III) and -10.852 and -0.019 kJ/mol for the dye removal. The regenerated CA-PVA-GO composite was reused successfully. Different physicochemical parameters, viz., concentration, pH, TDS, EC, BOD, and COD of chrome tanning and dyeing effluents, were analyzed before and after the adsorption. The results of chromium and dye removal from tannery wastewater were 53.18% and 93.91%, revealing that the developed eco-friendly CA-PVA-GO composite could be an operative adsorbent for tannery wastewater treatment and possibly scaled up to an industrial level.
PubMed: 38947873
DOI: 10.1016/j.scenv.2024.100092 -
ACS Omega Jun 2024The long- and short-range structural chemistry of the C-type bixbyite compounds ThNdCeO, ThNdCeO, and ThNdCeO is systematically examined using synchrotron X-ray powder...
Probing the Long- and Short-Range Structural Chemistry in the C-Type Bixbyite Oxides ThNdCeO, ThNdCeO, and ThNdCeO via Synchrotron X-ray Diffraction and Absorption Spectroscopy.
The long- and short-range structural chemistry of the C-type bixbyite compounds ThNdCeO, ThNdCeO, and ThNdCeO is systematically examined using synchrotron X-ray powder diffraction (S-PXRD), high-energy resolution fluorescence detection X-ray absorption near edge (HERFD-XANES), and extended X-ray absorption fine structure spectroscopy (EXAFS) measurements supported by electronic structure calculations. S-PXRD measurements revealed that the title compounds all form classical C-type bixbyite structures in space group 3̅ that have disordered cationic crystallographic sites with further observation of characteristic superlattice reflections corresponding to oxygen vacancies. Despite the occurrence of oxygen vacancies, HERFD-XANES measurements on the Ce L-edge revealed that Ce incorporates as Ce into the structures but involves local distortion that resembles cluster behavior and loss of nearest-neighbors. In comparison, HERFD-XANES measurements on the Nd L-edge supported by electronic structure calculations reveal that Nd adopts a local coordination environment similar to the long-range C-type structure while providing charge balancing for the formation of oxygen defects. Th L-edge EXAFS analysis reveals shorter average Th-O distances in the title compounds in comparison to pristine ThO in addition to shorter Th-O and Th-Ce distances compared to Th-Th or Ce-Ce in the corresponding F-type binary oxides (ThO and CeO). These distances are further found to decrease with the increased Nd content of the structures despite simultaneous observation of the overall lattice structure progressively expanding. Linear combination calculations of the M-O bond lengths are used to help explain these observations, where the role of oxygen defects, via Nd incorporation, induces local bond contraction and enhanced Th cation valence, leading to the observed increased lattice expansion with progressive Nd incorporation. Overall, the investigation points to the significance of dissimilar cations exhibiting variable short-range chemical behavior and how it can affect the long-range structural chemistry of complex oxides.
PubMed: 38947849
DOI: 10.1021/acsomega.4c02200 -
ACS Omega Jun 2024has been widely utilized in traditional Chinese medicine to treat dispelling wind and dampness and used for alleviating cough and diminishing inflammation. However, the...
has been widely utilized in traditional Chinese medicine to treat dispelling wind and dampness and used for alleviating cough and diminishing inflammation. However, the antioxidant, antimicrobial, and anti-inflammatory effects of leaves and the key active constituents remained elusive. So, we conducted some experiments to support the application of in traditional Chinese medicine by investigating the antioxidant, antibacterial, and anti-inflammatory abilities, and to identify the potential key constituents responsible for the activities. The ethanol extract of leaves (LCLE) was isolated and extracted, and assays measuring ferric reducing antioxidant power, total reducing power, DPPH, ABTS, and OH were used to assess its antioxidant capacities. Antimicrobial activities of LCLE were investigated by minimal inhibitory levels, minimum antibacterial concentrations, disc diffusion test, and scanning electron microscope examination. Further, experiments including macro indicators examination, histopathological examination, and biochemical parameters measurement were conducted to investigate the effects of LCLE on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice. LCLE was further isolated and purified through column chromatography, and LPS-induced RAW264.7 cells were constructed to assess the diminished inflammation potential of the identified chemical composites. ABTS and OH radicals were extensively neutralized by the LCLE treatment. LCLE administration also presented broad-spectrum antimicrobial properties, especially against by disrupting cell walls. LPS-induced ALI in mice was significantly ameliorated by LCLE intervention, as evidenced by the histological changes in the lung and liver tissues as well as the reductions of nitric oxide (NO), TNF-α, and IL-6 production. Furthermore, three novel compounds including fragransin B2, liriodendritol, and rhamnocitrin were isolated, purified, and identified from LCLE. These three compounds exhibited differential regulation on NO accumulation and IL-10, IL-1β, IL-6, TNF-α, COX-2, and iNOS mRNA expression in RAW264.7 cells induced by LPS. Fragransin B2 was more effective in inhibiting TNF-α mRNA expression, while rhamnocitrin was more powerful in inhibiting IL-6 mRNA expression. LCLE had significant antioxidant, antimicrobial, and anti-inflammatory effects. Fragransin B2, liriodendritol, and rhamnocitrin were probably key active constituents of LCLE, which might act synergistically to treat inflammatory-related disorders. This study provided a valuable view of the healing potential of leaves in curing inflammatory diseases.
PubMed: 38947843
DOI: 10.1021/acsomega.3c10269 -
ACS Omega Jun 2024Coalfield fires represent a critical environmental and safety concern, warranting a comprehensive understanding of the factors influencing the reactivity of oxidized...
Coalfield fires represent a critical environmental and safety concern, warranting a comprehensive understanding of the factors influencing the reactivity of oxidized coal residues within fire zones. This study investigates the influence of the oxygen volume fraction and oxidation temperature on the residual structure of oxidized coal, elucidating the underlying mechanisms driving reduced coal reactivity. The representative oxidation conditions for coalfield fire zones were determined. Through industrial and elemental analyses, complemented by methods such as infrared diffuse reflection, specific surface area determination, and pore size analysis, results indicate that higher temperatures and oxygen levels decrease volatile matter and fixed carbon, notably above 400 °C due to oxygen-deficient combustion. Hydroxyl groups decrease with a rising temperature in high oxygen conditions, while carboxyl groups increase at lower temperatures with elevated oxygen. Oxygen-lean and high-temperature conditions reinforce the coal structure, evidenced by the reduced condensation index in aromatic hydrocarbon. Oxidation alters the pore morphology, progressing from micropores to larger irregular pores through various stages, including pore formation, expansion, and merging. Elevated oxygen levels intensify oxidation, consuming the coal carbon matrix and reducing micropores, hindering internal gas diffusion, which is the key to a reduced coal reactivity in fire zones.
PubMed: 38947841
DOI: 10.1021/acsomega.4c03605 -
ACS Omega Jun 2024Electrospinning technology for fabricating nanofiber films and the Hummer method for synthesizing graphene oxide (GO), along with subsequent reduction, have been...
Electrospinning technology for fabricating nanofiber films and the Hummer method for synthesizing graphene oxide (GO), along with subsequent reduction, have been significantly advanced, demonstrating immense potential for large-scale industrial applications. Nanofibrous films loaded with reduced graphene oxide (rGO) have been widely explored for their applications in electromagnetic shielding, the biomedical fields, and pollutant adsorption. However, fragile mechanical performance of electrospun fibers with limited surface post-treatment methods has somewhat hindered their further industrial development. In response to this challenge, we propose a dual-regulation strategy involving post-treatment to form porous nanofiber films and the controlled flake size of rGO for surface coating during preparation. This approach aims to achieve poly(l-lactic acid) (PLLA)/rGO electrospun fibrous films with enhanced mechanical properties. It offers a roadmap for the continued application and standardized production of fibrous films loaded with rGO.
PubMed: 38947839
DOI: 10.1021/acsomega.4c01976 -
ACS Omega Jun 2024In the current study, we report the synthesis of a novel composite material composed of banana peel activated carbon (BPAC), nickel iron oxide (NiFeO), and manganese...
In the current study, we report the synthesis of a novel composite material composed of banana peel activated carbon (BPAC), nickel iron oxide (NiFeO), and manganese cobalt iron layered double hydroxide (MnCoFe-LDH) to create a high-performance electrochemical sensor to detect Palbociclib (PLB). The composite was successfully immobilized on a glassy carbon electrode (GCE) surface to create a modified electrode. The performance of the electrode was thoroughly evaluated, considering parameters such as electroactive surface areas (ESA), electron transfer rate constant (k), and exchange current density (j). The developed BPAC/NiFeO/MnCoFe-LDH/GCE exhibited a wide linear dynamic range of 0.01-13.0 μM for PLB concentration, accompanied by a detection limit at a low level (3.5 nM). Furthermore, it can be applied to the determination of PLB in human urine and pharmaceutical samples with excellent recoveries (98.5-102.9%) and RSD values lower than 3%, establishing its potential for precise PLB determination in pharmaceutical and biological samples. This research contributes to the advancement of electrochemical sensor technology for the detection of important anticancer drugs in real-world applications.
PubMed: 38947832
DOI: 10.1021/acsomega.4c02460 -
ACS Omega Jun 2024Toluene is a common and significant volatile organic compound (VOC). Although it finds extensive application in various industrial processes (chemical manufacturing,... (Review)
Review
Toluene is a common and significant volatile organic compound (VOC). Although it finds extensive application in various industrial processes (chemical manufacturing, paint and adhesive production, and as a solvent), it creates a huge environmental impact when emitted freely into the atmosphere. Two solutions were found to mitigate the emission of this pollutant: the total oxidation to CO and HO and the selective oxidation into benzaldehyde. This review discusses the two main alternatives for tackling this problem: converting the toluene into carbon dioxide by total oxidation or into benzaldehyde by selective oxidation. It presents new catalytic advances, new trends, and the advantages and disadvantages of both methods.
PubMed: 38947821
DOI: 10.1021/acsomega.4c01023 -
ACS Omega Jun 2024The advancement of water electrolyzer technologies and the production of sustainable hydrogen fuel heavily rely on the development of efficient and cost-effective...
The advancement of water electrolyzer technologies and the production of sustainable hydrogen fuel heavily rely on the development of efficient and cost-effective electrocatalysts for the oxygen evolution reaction (OER). High entropy ceramics, characterized by their unique properties, such as lattice distortion and high configurational entropy, hold significant promise for catalytic applications. In this study, we utilized the sol-gel autocombustion method to synthesize high entropy ceramics containing a combination of 3d transition metals and aluminum ((AlCrCoNiFe)O). We then compared their electrocatalytic performance with other series of synthesized multimetal and monometallic oxides for the OER under alkaline conditions. Our electrochemical analysis revealed that the high entropy ceramics exhibited excellent performance and the lowest charge transfer resistance, Tafel slope (29 mV·dec), and overpotential (η = 230 mV). These remarkable results can be primarily attributed to the high entropy effect induced by the addition of Al, Cr, Co, Ni, and Fe, which introduces increased disorder and complexity into the material's structure. This, in turn, facilitates more efficient OER catalysis by providing diverse active sites and promoting optimal electronic configurations for the reaction. Furthermore, the strong electronic interactions among the constituent elements in the metallic spinels further enhance their catalytic activity in the initiation of the OER process. Combined with the reduced charge transfer resistance, these factors collectively play pivotal roles in enhancing the OER performance of the electrocatalysts. Overall, our study provides valuable insights into the design and development of high-performance electrocatalysts for sustainable energy applications. By harnessing the high entropy effect and leveraging strong electronic interactions, electrocatalytic materials can be tailored to improve efficiency and stability, thus advancing the progress of clean energy technologies.
PubMed: 38947820
DOI: 10.1021/acsomega.4c03807