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Ignition delay times of the nitromethane (NM)/O2/Ar mixtures were measured behind reflected shock waves in the temperature range of 1200–2000 K, pressures of 2.0 and 10.0 atm, equivalence ratios of 0.5, 1.0, and 2.0, and fuel concentrations of 0.5%, 1.0%, and 2.0%. OH emission intensity and pressure evolution were used for the ignition delay time determination. Two-stage ignition behavior was observed in the experiments. The ignition delay time decreases sharply with pressure increasing and equivalence ratio decreasing. In addition, a sub-model including 24 updated reactions for nitromethane oxidation was proposed based on ab initio calculation with CCSD(T)/CBS//B3LYP/6–311 + G(3DF, 3P) level. The present model and the Mathieu's model (Mathieu et al. Fuel 182(2016): 597) were then validated against present measured ignition delay times, as well as some laminar flame speed data and ignition data in the literature. The present model shows better or comparable predictions with the experimental data. The main species concentration evolution and reaction analysis were presented, based on which the experimentally observed two-stage ignition behavior was interpreted. [ABSTRACT FROM AUTHOR]

Abstract: Densified ZrB2–SiC-based ultra-high temperature ceramics reinforced with short carbon fibers were prepared by conventional hot-pressing. The microstructure, mechanical and oxidation resistance properties of the composite were investigated. The Csf/ZrB2–SiC composite had improved fracture toughness of 6.6MPam1/2 compared to ZrB2–SiC composite of 4.3MPam1/2 due to fiber debonding, fiber pull-out and fiber bridging as well as crack deflection. It was found that the low modulus of carbon fiber and a graphitization transition layer between fiber and matrix led to the decreased flexural strength. The oxidation resistance tests were carried out on Csf/ZrB2–SiC using an oxyacetylene torch. The temperature of the oxidized specimen exceeded 1800°C and the surface layer appeared dense and adherent. No macro-cracks or spallation were detected, suggesting that these composites possess a better oxidation resistance than ZrB2–SiC. The improved oxidation resistance is attributed to the formation of a coherent SiO2 rich scale, which acts as an effective barrier against the inward diffusion of oxygen. The results presented here point to a potential way for improving toughness of composite without sacrificing oxidation protection. [Copyright &y& Elsevier]

Abstract: A ZrB2–20 vol.% SiC based ceramic matrix composite containing 20 vol.% short carbon fibers was top pressed at 2000 °C and 30 MPa for 1 h. The microstructure and mechanical properties of the composite were investigated. The fracture toughness was 6.56 MPa·m1/2, which is 54% higher than that of ZrB2–20 vol.% SiC composite. The toughening mechanisms were fiber debonding, fiber pull-out and crack deflection. Moreover, it was found that a graphitization transition layer between fiber and matrix led to the decreased in flexural strength. The results presented here point to a potential way for improving the fracture toughness of ultra-high temperature ceramics. [Copyright &y& Elsevier]

Three-dimensional Cu@Cu2O aerogels with excellent electrocatalytic activity were prepared and used as electrode matrix for constructing novel electrochemical glucose sensors. The aerogels were obtained by adding a fresh solution of NaBH4 into a mixture of CuCl2 and NaOH aqueous solutions under stirring at room temperature. The aerogels were assembled with Cu or Cu2O nanoparticles. The materials show superfine spongy-like structures with large surface-to-volume ratio, numerous active sites and good solubility. The Cu@Cu2O aerogels show highly efficient electrochemical activity toward glucose oxidation with a relatively low-onset potential (0.25 V) in 0.1 M NaOH solution. This non-enzymatic glucose sensor offers a low detection limit of 0.6 μM (S/N = 3), a high sensitivity (195 mA M−1 cm−2), and two wide linear ranges (0.001-5.2 mM, 5.2-17.1 mM) at a working voltage of 0.6 V (vs. Ag/AgCl) in alkaline solution. While in neutral pH values, the respective data are a linear analytical range from 0.1 to 10 mM; a detection limit of 54 μM (S/N = 3) and a sensitivity of 12 mA M−1 cm−2 at scan rate of 100 mV s−1. The sensor possesses high selectivity, good reproducibility and long-time stability. It was utilized to determine glucose levels in (spiked) human serum samples, and satisfactory results were obtained.Schematic presentation of a glassy carbon electrode modified with 3D porous Cu@Cu2O aerogels. The aerogels were obtained by a reduction reaction at room temperature (Scheme 1A). The aerogel networks were used to develop a highly sensitive electrochemical sensing platform for the detection of glucose (Scheme 1B). [ABSTRACT FROM AUTHOR]

[Display omitted] • HMCSs can be used as nano-reactors to control the growth of nickel silicate nanoflakes. • The core-shell superstructures significantly enhance the structural stability and conductivity of the Ni 3 Si 2 O 5 (OH) 4 /C materials. • The S1 electrode shows a superior SAC of 28.7 mg g−1 with an initial NaCl concentration of 584 mg L−1 at 1.2 V. In this work, we propose a novel strategy to fabricate nickel silicate nanoflakes inside hollow mesoporous carbon spheres (Ni 3 Si 2 O 5 (OH) 4 /C). Hollow mesoporous carbon spheres (HMCSs) can well regulate and limit the growth of Ni 3 Si 2 O 5 (OH) 4 nanosheets, which obviously enhance the structural stability and conductivity of the composites. The core-shell Ni 3 Si 2 O 5 (OH) 4 /C superstructure has been proven to possess an extremely excellent electrosorption capacity of 28.7 mg g−1 at 1.2 V under a NaCl concentration of 584 mg L−1 for capacitive deionization (CDI). This outstanding property can be attributed to the core-shell superstructure with ultrathin Ni 3 Si 2 O 5 (OH) 4 nanosheets as the stable core and mesoporous carbon as the conductive shell. This work will provide a direction for the application of core-shell superstructure carbon-based nanomaterials as high-performance electrode materials for CDI. [ABSTRACT FROM AUTHOR]

• DGE method detects forest disturbances with GMM and EM. • DGE outperforms traditional methods like ANAC, PGC, BL, and AI. • Broad DGE applications in disturbances, growth-climate relationship and other ecology fields. Forests have experienced unprecedented decline and mortality beyond their historical range in past decades, which is attributed to disturbances like drought, fire, insects and disease. Traditional disturbance detection methods that typically employ a time series perspective to identify discrete disturbance events within continuous tree growth signals and were mainly designed for gap-scale often fail to identify disturbances across populations. To more accurately identify growth suppression and release clusters based on the perspective of forest population dynamics, here we applied a novel method of detecting forest disturbances using a Gaussian mixture model with an expectation maximisation algorithm (DGE), to fit annual distributions of growth indicators, i.e., tree-ring index. We further compared our novel approach of DGE with five traditional methods based on two sets of real tree-ring data and simulated tree-ring data. The results show an improvement of accuracy (35.5 %–48.1 %), sensitivity (36.6 %–58.1 %), precision (21.2 %–51.5 %) and specificity (11.1 %–20.6 %) for the average of two real radial growth datasets and an improvement of accuracy (7.6 %–13.9 %), sensitivity (70 %), precision (100 %) and specificity (9.1 %–9.7 %) for the simulation radial growth dataset, indicating that our DGE approach performs much better than the traditional methods. This study contributes to an improved strategy and understanding for sustainable forest management in the context of climate warming, demonstrating that our DGE approach can be better applied to global forest disturbance detection under global change. [ABSTRACT FROM AUTHOR]

In regions experiencing cold weather, road icing poses significant challenges to transportation safety. Traditional anti-icing or de-icing methods, such as salt spraying, have raised environmental concerns, prompting the exploration of more sustainable alternatives. This study introduces a novel approach by developing a hydrophobic coating for road surfaces. This method involves using room-temperature vulcanized silicone rubber (RTV) and carbon nanotubes (CNTs) for the hydrophobic modification of emulsified asphalt (EA), resulting in the preparation of modified emulsified asphalt (RCEA). This method does not cause environmental pollution and makes the road surface highly hydrophobic and effective at preventing ice formation. When the dosages of RTV and CNTs are 20 wt% and 4 wt%, respectively, the contact angle of RCEA reaches 118.6°, showing a significant increase of 73.4 % compared to EA. Comparative tests have revealed that RCEA extends the freezing time of water droplets by 66.7 % at −10 °C compared to traditional emulsified asphalt (EA). Furthermore, the adhesion force of ice on the RCEA surface is 58.2 % lower than on EA, indicating significantly improved de-icing efficiency. The results of ultraviolet aging and freeze-thaw cycle tests show that RCEA maintains its hydrophobicity, evidenced by only a slight reduction in the contact angle. Additionally, water seepage coefficient tests and anti-skid performance assessments confirm that RCEA meets the requisite standards for road performance. In summary, RCEA emerges as a promising anti-icing and de-icing material for asphalt roads, offering an environmentally friendly alternative to traditional de-icing methods. • RCEA significantly delays the formation of ice on surfaces. • The ice adhesion of RCEA surface is substantially reduced. • RCEA has good durability and can preserve stable hydrophobicity properties. • RCEA has good road performance and can meet the requirements for road safety. [ABSTRACT FROM AUTHOR]

The road ice is a common phenomenon, which brings a safety risk to traffic. Carbon nanotube is an excellent photothermal conversion material. In outdoor environment, carbon nanotube can convert solar energy into heat energy to achieve the purpose of melting ice. In this paper, an emulsified asphalt coating modified by carbon nanotubes (CNTs) and polytetrafluoroethylene (PTFE) was prepared. During the preparation, we found that the optimal ratio of PTFE and CNTs is 1:1, and the optimal spraying amount is 400 ml/m2. The photothermal conversion performance test shows that the freezing time of water on the coating surface is significantly prolonged under near-infrared light irradiation. With the increase of light intensity, icing does not appear on coated surfaces. At the same time, the melting time of ice on the coating surface is about twice shorter than that on the unmodified asphalt surface under near-infrared irradiation. The superhydrophobic performance test shows that the contact angle of droplets on the coating surface can reach more than 150°, and the adhesion strength of ice on the coating surface is greatly reduced. The microscopic morphology of the coating shows that CNTs and PTFE are evenly distributed on the surface of the coating. To sum up, the photothermal hydrophobic coating has a good application potential for road anti-icing and de-icing. • CNTs/PTFE modified emulsified asphalt coating has superhydrophobicity. • The temperature of CNTs/PTFE modified emulsified asphalt coating increases by 13.4 ℃ under light irradiation. • CNTs/PTFE modified emulsified asphalt coating significantly prolongs the freezing time. • CNTs/PTFE modified emulsified asphalt coating has good durability and road performance. [ABSTRACT FROM AUTHOR]

The reaction kinetics of alkenes + hydroperoxyl (HȮ 2) system is of importance to low/intermediate temperature chemistry of alkanes. This work is a follow up of our previous study on 3-hexene + ȮH 1 ,. The rate coefficients were determined using the canonical variational transition-state theory. Results revealed that the asymmetric geometry of the HȮ 2 radical generated numerous reaction sub-channels. The rate coefficients, with a conservative uncertainty (factor of 5), were obtained to develop the detailed chemical mechanism of 3-hexene. Additionally, potential energy surface, minimum reaction path, adiabatic ground-state energy, and activation free Gibbs energy change (ΔG) calculations were also performed. [ABSTRACT FROM AUTHOR]

Numerous approaches targeting hepatic stellate cells (HSCs) have emerged as pivotal therapeutic strategies to mitigate liver fibrosis and are currently undergoing clinical trials. The investigation of herbal drugs or isolated natural active compounds is particularly valuable, due to their multifaceted functions and low risk of side effects. Recent studies have hinted at the potential efficacy of verbascoside (VB) in ameliorating renal and lung fibrosis, yet its impact on hepatic fibrosis remains to be elucidated. This study aims to evaluate the potential effects of VB on liver fibrosis by assessing its ability to inhibit HSC activation. VB demonstrated significant efficacy in suppressing the expression of fibrogenic genes in activated LX-2 cells. Additionally, VB inhibited the migration and proliferation of these activated HSCs by scavenging reactive oxygen species (ROS) and downregulating the AMPK pathway. Furthermore, a biosafe reverse microemulsion loaded with VB (VB-ME) was developed to improve VB's instability and low bioavailability. The optimal formulation of VB-ME was meticulously characterized, revealing substantial enhancements in cellular uptake, ROS-scavenging capacity, and the suppression of HSC activation.

Near-infrared region (NIR; 650-1700 nm) dyes offer many advantages over traditional dyes with absorption and emission in the visible region. However, developing new NIR dyes, especially organic dyes with long wavelengths, small molecular weight, and excellent stability and biocompatibility, is still quite challenging. Herein, we present a general method to enhance the absorption and emission wavelengths of traditional fluorophores by simply appending a charge separation structure, dihydropyridopyrazine. These novel NIR dyes not only exhibited greatly redshifted wavelengths compared to their parent dyes, but also displayed a small molecular weight increase together with retained stability and biocompatibility. Specifically, dye NIR-OX, a dihydropyridopyra-zine derivative of oxazine with a molecular mass of 386.2 Da, exhibited an absorption at 822 nm and an emission extending to 1200 nm, making it one of the smallest molecular-weight NIR-II emitting dyes. Thanks to its rapid metabolism and long wave-length, NIR-OX enabled high-contrast bioimaging and assessment of cholestatic liver injury in vivo and also facilitated the evalua-tion of the efficacy of liver protection medicines against cholestatic liver injury., (© 2024 Wiley‐VCH GmbH.)

Superhydrophobic surfaces exhibit considerable potential in road anti-icing applications due to their unique water-repellent properties. However, the nanorough structure of superhydrophobic coatings is highly susceptible to degradation under wheel rolling in practical applications. To maintain effective hydrophobicity under prolonged exposure to wheel rolling, a multilayer superhydrophobic anti-icing coating was developed. This coating utilizes antifreeze protein (AFP)-modified emulsified asphalt as the substrate with carbon nanotubes (CNTs) and silicon carbide (SiC) as surface coatings. Experimental results indicate that the inclusion of AFP enhances the viscosity of the emulsified asphalt, thereby stabilizing the nanorough structure of the coating. Even after 100 cycles of sandpaper grinding and 500 wheel rolls, the coating maintains robust hydrophobic properties. Moreover, when the coating is worn away by long-term high-strength loads, the exposed AFP-modified emulsified asphalt layer continues to exhibit effective anti-icing capabilities, significantly prolonging the complete freezing time of water droplets on its surface. Additionally, the incorporation of CNTs and SiC enhances the photothermal conversion performance, further improving the anti-icing efficiency of the coating under light irradiation. Overall, this coating shows promise for application in road anti-icing strategies.

The aim of this study is to solve the problems of the complicated pretreatment and high analytical cost in the detection technology of trace drugs and their metabolites in municipal wastewater. A high-performance magnetic sorbent was fsynthesized for the enrichment of trace drugs and their metabolites in wastewater to develop a magnetic solid-phase extraction pretreatment combined with the acoustic ejection mass spectrometry (AEMS) analytical method. The magnetic nanospheres were successfully prepared by magnetic nanoparticles modified with divinylbenzene and vinylpyrrolidone. The results showed that the linear dynamic range of 17 drugs was 1-500 ng/mL, the recovery was 44-100%, the matrix effect was more than 51%, the quantification limit was 1-2 ng/mL, and the MS measurement was fast. It can be seen that the developed magnetic solid-phase extraction (MSPE) method is a good solution to the problems of the complicated pretreatment and analytical cost in the analysis of drugs in wastewater. The developed magnetic material and acoustic excitation pretreatment coupled with mass spectrometry analysis method can realize the low-cost, efficient enrichment, and fast analysis of different kinds of drug molecules in urban sewage.

T cell immunity is critical for human defensive immune response. Exploring the key molecules during the process provides new targets for T cell-based immunotherapies. CMC1 is a mitochondrial electron transport chain (ETC) complex IV chaperon protein. By establishing in-vitro cell culture system and Cmc1 gene knock out mice, we evaluated the role of CMC1 in T cell activation and differentiation. The B16-OVA tumor model was used to test the possibility of targeting CMC1 for improving T cell anti-tumor immunity. We identified CMC1 as a positive regulator in CD8 + T cells activation and terminal differentiation. Meanwhile, we found that CMC1 increasingly expressed in exhausted T (Tex) cells. Genetic lost of Cmc1 inhibits the development of CD8 + T cell exhaustion in mice. Instead, deletion of Cmc1 in T cells prompts cells to differentiate into metabolically and functionally quiescent cells with increased memory-like features and tolerance to cell death upon repetitive or prolonged T cell receptor (TCR) stimulation. Further, the in-vitro mechanistic study revealed that environmental lactate enhances CMC1 expression by inducing USP7, mediated stabilization and de-ubiquitination of CMC1 protein, in which a mechanism we propose here that the lactate-enriched tumor microenvironment (TME) drives CD8 + TILs dysfunction through CMC1 regulatory effects on T cells. Taken together, our study unraveled the novel role of CMC1 as a T cell regulator and its possibility to be utilized for anti-tumor immunotherapy., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2024 The Author(s). Published with license by Taylor & Francis Group, LLC.)

Cardiac microtissues provide a promising platform for disease modeling and developmental studies, which require the close monitoring of the multimodal excitation-contraction dynamics. However, no existing assessing tool can track these multimodal dynamics across the live tissue. We develop a tissue-like mesh bioelectronic system to track these multimodal dynamics. The mesh system has tissue-level softness and cell-level dimensions to enable stable embedment in the tissue. It is integrated with an array of graphene sensors, which uniquely converges both bioelectrical and biomechanical sensing functionalities in one device. The system achieves stable tracking of the excitation-contraction dynamics across the tissue and throughout the developmental process, offering comprehensive assessments for tissue maturation, drug effects, and disease modeling. It holds the promise to provide more accurate quantification of the functional, developmental, and pathophysiological states in cardiac tissues, creating an instrumental tool for improving tissue engineering and studies., (© 2024. The Author(s).)

In early neurodevelopment, the central nervous system is established through the coordination of various neural organizers directing tissue patterning and cell differentiation. Better recapitulation of morphogen gradient production and signaling will be crucial for establishing improved developmental models of the brain in vitro. Here, we developed a method by assembling polydimethylsiloxane devices capable of generating a sustained chemical gradient to produce patterned brain organoids, which we termed morphogen-gradient-induced brain organoids (MIBOs). At 3.5 weeks, MIBOs replicated dorsal-ventral patterning observed in the ganglionic eminences (GE). Analysis of mature MIBOs through single-cell RNA sequencing revealed distinct dorsal GE-derived CALB2 + interneurons, medium spiny neurons, and medial GE-derived cell types. Finally, we demonstrate long-term culturing capabilities with MIBOs maintaining stable neural activity in cultures grown up to 5.5 months. MIBOs demonstrate a versatile approach for generating spatially patterned brain organoids for embryonic development and disease modeling., Competing Interests: Declaration of interests The authors listed (Y.S., C.P., F.Y., and N.P. ) have filed a provisionary patent related to this work (Docket Number: UMA 23-023, Title: “A chemical gradient inducing device and methods for developing patterned organoids.”)., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Hyperlipidaemia, a common chronic disease, is the cause of cardiovascular diseases such as myocardial infarction and atherosclerosis. Generally, drugs for lowering blood lipids have disadvantages such as short or poor efficacy, high toxicity, and side effects. Rapeseed active peptides are excellent substitutes for lipid-lowering drugs because of their high biological safety, strong penetration, and easy absorption by the human body. This study separated and purified the rapeseed peptides using gel chromatography and mass spectrometry. Rapeseed peptides amino acid sequences were determined to obtain Glu-Phe-Leu-Glu-Leu-Leu (EFLELL) peptides with good hypolipidaemic activity and IC 50 values of 0.1973 ± 0.05 mM (sodium taurocholate), 0.375 ± 0.03 mM (sodium cholate), and 0.203 ± 0.06 mM (sodium glycine cholate). The EFLELL hypolipidaemic activity was evaluated, and its mechanism of action was investigated using cell lines. Rapeseed peptide treatment significantly decreased the total cholesterol (T-CHO), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) levels, and the protein and gene expression levels of proprotein convertase subtilisin/kexin type 9 (PCSK9) and low-density lipoprotein cholesterol (LDLR) suggested the mechanism. Molecular docking revealed that the binding energy between rapeseed peptide and LDLR-PCSK9 molecules was -6.3 kcal/mol and -8.1 kcal/mol. In conclusion, the rapeseed peptide EFLELL exerts a favourable hypolipidaemic effect by modulating the LDLR-PCSK9 signalling pathway., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Background: With the advent of immune checkpoint inhibitors (ICIs) therapies, a major breakthrough has been made in cancer treatment. However, instead of good results, some patients experienced a deterioration of their disease. This unexpected result is termed as hyper-progressive disease (HPD). The biology of HPD is currently not fully understood., Methods: Isolation of CD3 + cells from peripheral blood mononuclear cells (PBMC) in healthy control, tumor patients receiving immunotherapy with or without immunotherapy-induced HPD, then conducted single-cell RNA sequencing (scRNA-seq)., Results: By analyzing scRNA-seq data, we identified 15 cell clusters. We observed developed-exhausted CD4 + T cells and regulatory T cells (Tregs) increasingly enriched in HPD group. Meanwhile, some effector T cells were decreased in HPD. The imbalance potentially contributes to the occurrence of HPD and poor clinical prognosis. In addition, we analyzed ligand-receptor interactions between subsets. The ligand-receptor interaction "CD74-MIF" was absent in HPD. However, in vitro experiment, we found that CD74 regulated effector function of effector CD8 + T cells. Overall, the article provides a primary study of immune profile in HPD., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Exploring an emerging carbon-based material with optimized structure and controlled porosity is of significance for further heightening the capacitive deionization (CDI) performance and solving the problem of emergency fresh water supply. Herein, a porous nitrogen-doped carbon nanopolyhedra with hierarchical pores prepared via using zeolite-type metal-organic framework (ZIF-8) as precursor is reported and used for CDI. In order to prepare the nanomaterials with abundant hierarchical pore structure, the synthetic route of carbonization followed by HCl-activation is adopted. The resulting nitrogen-doped carbon materials exhibit a bimodal porosity containing micro- and meso-pores, high specific surface area, and numerous exposed adsorption active sites. The excellent performance in structure ensures the ultrahigh desalination capacity of 37.52 mg g -1 and excellent recyclability (retained 90% over 30 cycles) of the as-prepared carbon electrode material. Notably, the above electrode demonstrates ultrafast desalination rate of 16.01 mg g -1  min -1 , which is 2-8 times faster than the conventional carbon materials. This present work may provide a new insight for developing efficient MOF-derived CDI electrode materials and realizing rapid water resource supply in emergencies such as outdoor survival or unexpected natural disasters., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

This study aimed to identify the sources of volatile sulphur compounds (VSCs) and evaluate their mitigation by ferric oxide (Fe 2 O 3 ) during swine manure composting. Four chemicals, including l-cysteine, l-methionine, sodium sulphite, and sodium sulphate, were further added to simulate organic and inorganic sulphur-containing substances in swine manure to track VSC sources during composting. Results show that sulphur simulants induced the emission of six common VSCs, including methyl sulphide (Me 2 S), dimethyl sulphide (Me 2 SS), carbonyl sulphide (COS), carbon disulphide (CS 2 ), methyl mercaptan (MeSH), and ethyl mercaptan (EtSH), during swine manure composting. Of them, COS, CS 2 , MeSH and Me 2 SS were predominantly contributed by the biodegradation of methionine and cysteine, while Me 2 S and EtSH were dominated by the reduction of sulphite and sulphate. Further Fe 2 O 3 addition at 1.5 % of total wet weight of composting materials immobilized elemental sulphur and inhibited sulphate reduction to reduce the emission of VSCs by 46.7-80.9 %. Furthermore, odour assessment indicated that adding Fe 2 O 3 into composting piles significantly reduced the odour intensity level to below 4, the odour value of VSCs by 47.1-81.3 %, and thus the non-carcinogenic risk by 68.4 %., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Control and detection of sunset yellow (SY) are an utmost demanding issue due to its high risk of detrimental effects on living systems caused by excessive ingestion. In this study, we reported the synthesis of Cu@Cu 2 O nanoparticle-decorated B and N codoped porous carbon (BNPC) and its use in developing a novel electrochemical sensor for SY. The Cu@Cu 2 O-BNPC catalyst was fabricated through single-step polymerization, followed by carbonization. Scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy characterization results showed that Cu@Cu 2 O anchored on the porous BNPC successfully. Compared with the BNPC-modified electrode, it was found that the Cu@Cu 2 O-BNPC-modified electrode showed superior electrocatalytic activity in both electrochemical impedance spectroscopy and cyclic voltammetry tests. The as-prepared Cu@Cu 2 O-BNPC catalyst directly acted as a sensor for amperometric detection of SY without further assembling, which exhibited an ultrahigh sensitivity of 0.09 μA nM -1 cm -2 , a low limit of detection (2.4 nM), and a wide linear detection ranging from 10 nM to 8 μM. To further validate its possible application, the proposed method was successfully used for the determination of SY in Fanta drinks with satisfactory results., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

As a renewable source of energy, ethanol has been widely used in internal combustion engines as either a gasoline alternative fuel or a fuel additive. However, as the chemical source term of the computational fluid dynamics simulation of combustors, there remains a disagreement in understanding the chemical kinetic mechanism of ethanol. The reaction mechanism of ethanol + HȮ 2 is a well-known crucial reaction class in terms of predicting the reactivity of ethanol as well as ethylene formation under engine-relevant conditions. However, the kinetic parameters of the reactions are basically extrapolated by analogy to the n-butanol + HȮ 2 system calculated by Zhou et al. (Zhou et al. Int. J. Chem. Kinet. 2012, 44 (3), 155-164). The reliability of such an analogy remains to be seen because no direct theoretical or experimental evidence is available in the literature to date. In this study, thermal rate coefficients of H-atom abstraction reactions for the ethanol + HȮ 2 system were determined by using both conventional transition-state theory and canonical variational transition-state theory, with the potential energy surface evaluated at the CCSD(T)/cc-pVTZ//M06-2x/def-TZVP level. The quantum-mechanical effects were corrected by the zero-curvature tunneling method at low temperatures (<750 K), and difference schemes of two Eckart functions were fitted to optimize the minimum energy path curves. Torsional modes of the -CH 3 and -OH groups were treated by using the hindered-internal-rotation approximation. Furthermore, the rate coefficients of the title reaction were calculated at both the CCSD(T)/cc-pVTZ//M06-2x/def-TZVP and CCSD(T)/CBS//M06-2x/def-TZVP levels of theory with uncertainty of a factor of 3. Similar to the n-butanol + HȮ 2 system, the title system is dominated by α-site H-atom abstraction, but the rate coefficients of the three channels are slightly slower than that of the n-butanol + HȮ 2 system. In general, the new calculations show only a limited effect on the ethanol reactivity at low pressures and high temperatures (>1300 K), but they prevent the kinetic mechanisms from overpredicting ignition delay times under engine-relevant conditions.