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This paper considers a class of multi-agent distributed convex optimization with a common set of constraints and provides several continuous-time neurodynamic approaches. In problem transformation, l 1 and l 2 penalty methods are used respectively to cast the linear consensus constraint into the objective function, which avoids introducing auxiliary variables and only involves information exchange among primal variables in the process of solving the problem. For nonsmooth cost functions, two differential inclusions with projection operator are proposed. Without convexity of the differential inclusions, the asymptotic behavior and convergence properties are explored. For smooth cost functions, by harnessing the smoothness of l 2 penalty function, finite- and fixed-time convergent algorithms are provided via a specifically designed average consensus estimator. Finally, several numerical examples in the multi-agent simulation environment are conducted to illustrate the effectiveness of the proposed neurodynamic approaches. [ABSTRACT FROM AUTHOR]

Different bimetallic platinum and bismuth catalysts supported on melamine‐modified activated carbon (AC) are designed by a co‐impregnation method. Through controlling the activation temperatures of the melamine−AC mixture, a series of N‐doped and C3N4‐modified AC (N−AC and C3N4−AC) are prepared. Combined powder X‐ray diffractions, X‐ray photoelectron spectroscopic, and high‐angle annual dark‐field scanning transmission electron microscopic studies demonstrate that the introduction of C3N4 favors the formation of PtBi alloy and leads to increased particle sizes in comparison to the pristine and N‐doped AC‐supported bimetallics. The catalytic performance of the developed catalysts is evaluated in the oxidation of n‐heptanol oxidation in a batch mode using O2 as the oxidant. PtBi/C3N4−AC exhibits significantly boosted activity as well as selectivity to heptanoic acid as compared with the other catalysts. A high yield of heptanoic acid of 69 % can be achieved under the optimized reaction conditions. Furthermore, our work points to the PtBi alloy as the most active sites for the alcohol oxidation. Catalyst deactivation occurs in the cycling tests, mainly due to the collapse of the alloy phase and likely the decrease in particle sizes. [ABSTRACT FROM AUTHOR]

Under the development trend of large-size antennas, the demand for modular expansion of synthetic aperture radar antennas is increasing, and the connection mechanism is an important part of the modular expansion. This paper designed and studied the connection mechanism between the basic units of the planar deployable antenna mechanism. Firstly, for the basic deployable units of a new type of planar deployable antenna spatial support mechanism proposed previously by the author, the connection mechanism between the basic units was synthesized, and a series of feasible planar deployable mechanism configurations were obtained. Meanwhile, a spatial support mechanism for planar deployable antennas with scissor was optimally constructed by analysis. Through finite element comparative analysis, it was found that the mechanism improves the stiffness and reduces the maximum deformation. Then, scale optimization was performed by using the control variable method. Finally, the prototype was developed, and experimental research was conducted to verify the feasibility of the mechanism. The spatial support mechanism of the planar deployable antenna with scissor proposed in this paper improves the reliability, stiffness, modal, and other related properties of the unfolding process. Therefore, it has broad application prospects in the field of aerospace deployable antennas. • Propose a method to design the connection mechanism between the basic deployable units. • Design a spatial support mechanism for planar deployable antenna without P joints. • Compare the stiffness of the new mechanism and the previous one. • Develop a prototype of the proposed support mechanism and validate the motion principle. [ABSTRACT FROM AUTHOR]

The Turing pattern is an important dynamic behavior characteristic of activator–inhibitor systems. Differentiating from traditional assumption of activator–inhibitor interactions in a spatially continuous domain, a Turing pattern in networked reaction-diffusion systems has received much attention during the past few decades. In spite of its great progress, it still fails to evaluate the precise influences of network topology on pattern formation. To this end, we try to promote the research on this important and interesting issue from the point of view of average degree—a critical topological feature of networks. We first qualitatively analyze the influence of average degree on pattern formation. Then, a quantitative relationship between pattern formation and average degree, the exponential decay of pattern formation, is proposed via nonlinear regression. The finding holds true for several activator–inhibitor systems including biology model, ecology model, and chemistry model. The significance of this study lies that the exponential decay not only quantitatively depicts the influence of average degree on pattern formation, but also provides the possibility for predicting and controlling pattern formation. [ABSTRACT FROM AUTHOR]

In this paper, a novel spatial support mechanism for planar deployable antennas is designed based on the motion principle of planar deployable antennas and the spatial mechanism theory. The composition principle of the novel mechanism and its geometric characteristics are analyzed, and its degrees of freedom are calculated based on the constraint topological diagram. Subsequently, kinematic analysis is conducted, and the angular velocity, linear velocity, and linear acceleration of each component in the mechanism are calculated. Then, numerical calculation and simulation are performed to verify the correctness of the theoretical analysis results. The performance analysis of the spatial support mechanism is completed. A prototype of the proposed support mechanism is developed and tested to validate the feasibility of the mechanism principle. The present work can provide reference for the design and engineering application of this type of mechanisms. • 1.Propose a novel support mechanism for planar deployable antennas. • 2.Analyze the DOFs, kinematics, dynamics based on the constraint topological diagram. • 3.Develop a prototype of the proposed support mechanism and validate the motion principle. [ABSTRACT FROM AUTHOR]

Pesticide residues in grapes could be transferred to fermentation system during the wine-making process, which may interfere the normal proliferation of Saccharomyces cerevisiae and subsequently affect the safety and quality of wine products. However, the interaction between pesticides and Saccharomyces cerevisiae is still poorly understood. Herein, the fate, distribution and interaction effect with Saccharomyces cerevisiae of five commonly-used pesticides during the wine-making process were evaluated. The five pesticides exerted varied inhibition on the proliferation of Saccharomyces cerevisiae , and the order of inhibition intensity was difenoconazole > tebuconazole > pyraclostrobin > azoxystrobin > thiamethoxam. Compared with the other three pesticides, triazole fungicides difenoconazole and tebuconazole showed stronger inhibition and played a major role in binary exposure. The mode of action, lipophilicity and exposure concentration were important factors in the inhibition of pesticides. Saccharomyces cerevisiae had no obvious impacts on the degradation of target pesticides in the simulated fermentation experiment. However, the levels of target pesticides and their metabolite were significantly reduced during the wine-making process, with the processing factors ranged from 0.030 to 0.236 (or 0.032 to 0.257) during spontaneous (or inoculated) wine-making process. As a result, these pesticides were significantly enriched in the pomace and lees, and showed a positive correlation (R2 ≥ 0.536, n = 12, P < 0.05) between the hydrophobicity of pesticides and distribution coefficients in the solid-liquid distribution system. The findings provide important information for rational selection of pesticides on wine grapes and facilitate more accurate risk assessments of pesticides for grape processing products. [Display omitted] • Difenoconazole and tebuconazole strongly inhibited on Saccharomyces cerevisiae. • Action mode, lipophilicity and concentration were key factors in inhibition of pesticide. • Five pesticide residues were obviously reduced in wine after wine-making process. • Lipophilic pesticides tended to be enriched in the pomace and lees. [ABSTRACT FROM AUTHOR]

• Two model buildings are specially built for comparative study. • Dynamic monitoring of external insulation for improving thermal environment and energy saving during heating. • The time for EPS building to approach the air temperature set value has no obvious advantage. • The energy saving effect of short-time heating operation of EPS building is very weak. • A dynamic index is proposed to evaluate the improvement effect of external insulation on indoor thermal environment. In this paper, two identical model buildings were built, one of which adopted 38 mm Expanded Polystyrene (EPS) board as the external insulation. Under the same heating set-point temperature, the dynamic change process of indoor thermal environment and heating energy consumption of EPS insulation building and non-insulation Reference building was compared and monitored. Results show that under the same heating set-point temperature, the indoor temperature of the two buildings can quickly approach the set value in about 20 min. However, the temperature rise of the internal surface of the wall lags behind. After several hours, the advantage of the temperature rise of the internal surface of the EPS building gradually appeared. The energy consumption of the two buildings is similar in the initial heating period of 20 min, and the energy saving rate of EPS building increases slowly with the increase of the heating duration. The energy saving rate is about 1%–26% in the range of 0.5–8 h intermittent heating in hot summer and cold winter zone. The change curve of cumulative temperature rise ratio with heating time is proposed to evaluate the dynamic improvement effect of external insulation on indoor thermal environment. This research provides a reference basis for the development of energy conservation. [ABSTRACT FROM AUTHOR]

The shape of the carriers has a profound impact on the catalytic performance of metal‐supported catalysts. Herein, ZrO2 of different shapes (nanorods‐like, spherical or irregular nanoparticles, demoted as RZ, SPZ, and IPZ, respectively) are adopted to disperse Ni species to assess the shape effects on the catalytic performance in dry reforming of methane. To this end, the fresh and spent catalysts are thoroughly characterized by multiple techniques including N2 sorption, powder X‐ray diffraction, temperature‐programmed reduction with H2, thermogravimetric analyses, transmission electron microscopy, Raman and X‐ray photoelectron spectroscopies. It is revealed that the reducibility of NiO species follows the orders of Ni/RZ

Nitrogen-doped carbons (NC) and carbon nitride (C 3 N 4) belong to the two fundamental pillars of functionalized carbon materials that have broad applications in different fields. The synthesis of NC and C 3 N 4 often starts from different precursors, and a general approach that can offer both architectures is still highly sought. Herein, a facile Triton X-100-assisted copolymerization-carbonization strategy is reported to fulfill this task. By moderating the weight ratios of Triton X-100 and several conventional precursors of C 3 N 4 (e.g., dicyandiamide, urea, and cyanamide), a series of both types of N-functionalized carbons with controllable N dopants is successfully afforded. The yielded solids transform from graphitic C 3 N 4 with low surface areas to porous NC when the weight ratio reaches the critical values. This phenomenon might be attributed to the intensified copolymerization between the intermediates of both starting precursors during the carbonization, resulting in increased oxygen content and decreased N:C ratio in the products. Both the bulk and activated carbon-supported materials are then designed and used as metal-free catalysts in the dehydrochlorination of ethylene dichloride, a key reaction in polyvinyl chloride manufacture. It is found that NC is significantly more active than C 3 N 4 , but the corresponding supported catalysts exhibit an opposing trend. The structure-activity correlations suggest both the number of different N defects and the surface areas might play key roles in determining the dehydrochlorination chemistry. Tailor synthesis of C 3 N 4 and N-doped carbons with controllable N defects was enabled by a newly developed approach through co-pyrolysis of Triton X-100 and conventional C 3 N 4 precursors. [Display omitted] [ABSTRACT FROM AUTHOR]

The complex and changeable environment is a brand-new living condition for the viruses and pathogens released by the infected people to the indoor air or deposited on the surface of objects, which is an important external condition affecting the decay and transmission risk of the viruses. Exposure to contaminated surfaces is one of the main routes of respiratory diseases transmission. Therefore, it is very important for epidemic prevention and control to study the law of virus decay and the environmental coupling effect on various surfaces. Based on the analysis of the influencing mechanism, a large amount of experimental evidence on the survival of viruses on the surface of objects were excavated in this paper, and the effects of various factors, such as surface peripheral temperature, relative humidity, virus-containing droplet volume, surface materials and virus types, on the decay rate constants of viruses were comprehensively analyzed. It was found that although the experimental methods, virus types and experimental conditions varied widely in different experiments, the virus concentrations on the surface of objects all followed the exponential decay law, and the coupling effect of various factors was reflected in the decay rate constant k. Under different experimental conditions, k values ranged from 0.001 to 100 h−1, with a difference of 5 orders of magnitude, corresponding to the characteristic time t 99 between 500 and 0.1 h when the virus concentration decreased by 99%. This indicates a large variation in the risk of virus transmission in different scenarios. By revealing the common law and individuality of the virus decay on the surface of objects, the essential relationship between the experimental observation phenomenon and virus decay was analyzed. This paper points out the huge difference in virus transmission risk on the surface at different time nodes, and discusses the prevention and control strategies to grasp the main contradictions in the different situations. • The effects of different environmental factors on the virus decay constants k were analyzed. • k values ranged from 0.001 to 100 h−1, with a difference of 5 orders of magnitude. • In moderate relative humidity environments (30–60% RH) the k values were higher. • A quantitative expression of the decay rate constant k and each characteristic time was provided. • Prevention and control should focus on the initial stage after surface were contaminated. [ABSTRACT FROM AUTHOR]

Cleistocalyx operculatus and Syzygium cumini possess a certain waterlogging tolerance. However, the comparable and adaptable strategies to waterlogging stress between these two species on the basis of waterlogging adventitious root (AR) regulation were still unclear. In this study, the plant performance in response to AR regulation based on AR removal (AR-R) and exogenous hormone application was investigated in terms of plant morphology, physiology, photosynthesis and AR traits. Results showed that C. operculatus possesses stronger waterlogging tolerance than S. cumini based on waterlogging tolerance coefficient, which is mainly due to the higher root biomass, root porosity and length, and activity of ARs, and shorter emergence time of ARs in C. operculatus than in S. cumini. The AR-R treatment increased activity and porosity of primary root, and induced a large amount of up-vertical ARs from the primary root systems in C. operculatus , while similar adaptive morphological changes in roots did not occur in AR-R-treated S. cumini. Exogenous abscisic acid (ABA) application had better effects on alleviating waterlogging damages than exogenous auxin (IAA) in balancing endogenous hormones (ABA and zeatin riboside), promoting AR development (porosity and activity, and the ratio of cortex area to stele area), improving the photosynthesis process and the antioxidant system (soluble protein, free proline and peroxidase). Moreover, under waterlogging conditions, exogenous ABA application induced greater increases in net photosynthesis rate, stomatal conductance, chlorophyll b and carotenoid in S. cumini than in C. operculatus , which suggested that S. cumini responded more positively and efficiently to exogenous ABA application than C. operculatus under waterlogging conditions. Thus, the findings provided new insights into the waterlogging adaptable strategies in waterlogging tolerant woody species on the basis of ARs and could provide scientific guidance for the application of these two species during revegetation activities in wetlands. Cleistocalyx operculatus could alternatively form a majority of up-vertical adventitious roots (ARs) from the primary roots after removing the normal ARs, but Syzygium cumini could not. Cleistocalyx operculatus possessed positive strategies to waterlogging stress, while S. cumini used traditional passive strategies. Exogenous abscisic acid (ABA) application had better effects on alleviating waterlogging damages in both species than exogenous auxin application. Syzygium cumini could more positively and efficiently respond to exogenous ABA application than C. operculatus. Waterlogging tolerance coefficient was significantly controlled by the chlorophyll contents and AR factors in C. operculatus and the AR factors and O2− in S. cumini. The best development of the AR number (ARN) and AR length (ARL) in exogenous ABA-treated C. operculatus may be closely related with positive zeatin riboside accumulation. The development of ARN and ARL was more important to waterlogging tolerance than that of AR porosity under waterlogging conditions. [ABSTRACT FROM AUTHOR]

Accelerated urbanization has increased regional traffic congestion. To alleviate traffic congestion in a homogeneous road network, combined with the advantage of real-time traffic information obtained by the Internet of Vehicles (IoVs), a boundary guidance strategy for traffic congestion region is proposed. The strategy considers the optimal operation state of traffic congestion region and is divided into two categories according to different destinations of traffic demands. Meanwhile, a method for the boundary guidance strategy is presented in which the macroscopic fundamental diagram (MFD) is used to determine the optimal accumulation, a traffic flow equilibrium model is established to calculate the real-time accumulation, and a fuzzy adaptive PID control algorithm is designed to calculate the optimal traffic inflow of the traffic congestion region. Furthermore, an example is selected for simulation. The results show that the boundary guidance strategy can effectively improve the operational state of the road network and alleviate traffic congestion. Finally, the influence of connected vehicle penetration rate on the strategy is discussed. The simulation results show that the strategy can improve the operation state of the road network under mixed traffic flow, and the higher the penetration rate, the more significant its effect on alleviating traffic congestion. [ABSTRACT FROM AUTHOR]

During ageing, adult stem cells' regenerative properties decline, as they undergo replicative senescence and lose both their proliferative and differentiation capacities. In contrast, embryonic and foetal progenitors typically possess heightened proliferative capacities and manifest a more robust regenerative response upon injury and transplantation, despite undergoing many rounds of mitosis. How embryonic and foetal progenitors delay senescence and maintain their proliferative and differentiation capacities after numerous rounds of mitosis, remains unknown. It is also unclear if defined embryonic factors can rejuvenate adult progenitors to confer extended proliferative and differentiation capacities, without reprogramming their lineage‐specific fates or inducing oncogenic transformation. Here, we report that a minimal combination of LIN28A, TERT, and sh‐p53 (LTS), all of which are tightly regulated and play important roles during embryonic development, can delay senescence in adult muscle progenitors. LTS muscle progenitors showed an extended proliferative capacity, maintained a normal karyotype, underwent myogenesis normally, and did not manifest tumorigenesis nor aberrations in lineage differentiation, even in late passages. LTS treatment promoted self‐renewal and rescued the pro‐senescence phenotype of aged cachexia patients' muscle progenitors, and promoted their engraftment for skeletal muscle regeneration in vivo. When we examined the mechanistic basis for LIN28A's role in the LTS minimum combo, let‐7 microRNA suppression could not fully explain how LIN28A promoted muscle progenitor self‐renewal. Instead, LIN28A was promoting the translation of oxidative phosphorylation mRNAs in adult muscle progenitors to optimize mitochondrial reactive oxygen species (mtROS) and mitohormetic signalling. Optimized mtROS induced a variety of mitohormetic stress responses, including the hypoxic response for metabolic damage, the unfolded protein response for protein damage, and the p53 response for DNA damage. Perturbation of mtROS levels specifically abrogated the LIN28A‐driven hypoxic response in Hypoxia Inducible Factor‐1α (HIF1α) and glycolysis, and thus LTS progenitor self‐renewal, without affecting normal or TS progenitors. Our findings connect embryonically regulated factors to mitohormesis and progenitor rejuvenation, with implications for ageing‐related muscle degeneration. [ABSTRACT FROM AUTHOR]

The direct conversion of biomass-derived ethanol to high-valued-added chemicals has attracted widespread attention recently due to the great economic and environmental advantages. In the present study, the conversion of bioethanol through the Guerbet coupling process was studied in a fixed-bed reactor for MgAlOx and ZnAlOx mixed-oxides supported Cu catalysts. From the results, Cu adding into the system greatly enhance the dehydrogenation of ethanol and increase the H-transfer in the course of Guerbet coupling process. Simultaneously, the porous mixed-oxides provide the acid-base property of the catalysts for intermediate transformation. Notably, for Cu/MgAlOx, the main product of ethanol conversion is butanol, but for Cu/ZnAlOx, the primary product is ethyl acetate. Characterizations such as X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and CO2 temperature programmed desorption (TPD) were carried out to evaluate the structure and property of the catalysts. In combination with the catalytic performances with the characterization results, the synergistic catalytic effect between metal sites and acid-base sites were elaborated. [ABSTRACT FROM AUTHOR]

BACKGROUND: Pesticide contamination in oil crops and processed products is an important food safety concern. The study was aimed to investigate the pesticide residue changes in press processing of peanut oil and frying of chips. RESULTS: Five pesticides – chlorpyrifos, deltamethrin, methoxyfenozide, azoxystrobin and propargite – which are often applied during growth period in peanut plants, were selected to investigate their residue changes in cold press processing of peanut oil and frying of potato chips. Results showed that the residues of the five pesticides were decreased by 3.1–42.6% during air‐drying before oil pressing. The residues of chlorpyrifos, deltamethrin, methoxyfenozide and propargite in peanut oil were 2.05–3.63 times higher than that in peanut meal after cold pressing of the oil, except for azoxystrobin having a slightly lower residue in peanut oil, with 0.92 times that in peanut meal. The processing factors of the five pesticides in peanut oil ranged from 1.17 to 2.73 and were highly related to the log Kow of the pesticides. The higher the log Kow, the more easily was the pesticide partitioned in the peanut oil. Besides, as frying time increase during preparation of chips, the concentration of pesticides in peanut oil decreased gradually by 6.7–22.1% compared to the first frying. In addition, 0.47–11.06% of the pesticides were transferred to the chips through frying with contaminated oil. CONCLUSION: This is first report showing that pesticides can transfer from contaminated oil to chips. There exists a potential dietary health risk by using pesticide‐contaminated oil for frying chips. This work could provide basic data for accurate dietary risk assessment of pesticide residues in peanut oil and its frying products. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The adsorption properties of shale oil are of great significance to the development of shale oil resources. This study is aimed at understanding the microscopic adsorption mechanism of shale oil in organic nanopores. Thus, a molecular model of organic micropore walls and multicomponent fluids of CO2, C4H10, C8H18, and C12H26 is constructed to investigate the adsorption pattern of multicomponent fluids in organic nanopores under different temperature and pore size conditions. The quantity and heat of adsorption are simulated with the Monte Carlo method, which has been used in previous studies for single-or two-component fluids. The results demonstrate that the ability of CO2 to displace various alkanes is different. Specifically, medium-chain n-alkanes are slightly weaker than light alkanes in competitive sorption, and long-chain n-alkanes are less conducive to competitive sorption. The higher the CO2 sorption ratio, the more the sorption sites occupied by CO2. Thus, it is the best replacement for shale oil. The adsorption quantity of carbon dioxide, n-butane, and n-octane in organic nanopores first increases and then decreases as temperature rises. Meanwhile, the adsorption quantity of n-dodecane decreases firstly and then increases. With the increase in the pore size, the adsorption quantity of carbon dioxide, n-butane, and n-octane in organic nanopores increases while the adsorption quantity of n-dodecane first increases and then decreases. Besides, the model with larger pore sizes is more sensitive to pressure changes in the adsorption of carbon dioxide and n-butane than the model with smaller pore sizes. The heat of adsorption is CO2, C12H26, C8H18, and C4H10 in descending order. All are physical adsorption. Moreover, the adsorption quantity of all four components mixed fluid in the organic matter nanopores is positively correlated with the heat of adsorption. [ABSTRACT FROM AUTHOR]

With the continuous development of society, the social division of labor is further improved, and social production tends to be highly specialized and industrialized. Moreover, enterprise production is increasingly internationalized, and sales are gradually expanding. Therefore, the multi-objective sequencing in logistics distribution is incorporated into the path optimization of the logistics system, and a multi-objective bi-level programming model of time and cost is established. What is more, considering the limitations of the traditional algorithm in solving multi-objective problems, the low-dimensional multi-objective problem is selected, and according to the actual situation, the inheritance strategy of genetic factors is adopted to solve the more targeted rapid dominating sorting genetic problem. Besides, the specific conditions and characteristics of the model determine the encoding method, which is brought into the operation of the cross-mutation law and the interruption of individual populations, so that the building foundation of the model is improved. Based on the further theoretical research on the distribution efficiency of logistics system, the corresponding mathematical model is constructed by using the planning method, and the single cost target is transformed into the time and cost double objective, and the improved fast non dominated sorting genetic algorithm with elite strategy is used to solve the problem, which has certain theoretical innovation. Through simulation, the optimal or near optimal path of distribution vehicles in a certain area is given, which has certain practicality and reference value for the optimization of actual logistics distribution path. [ABSTRACT FROM AUTHOR]

A rapid and sensitive ultra-high-performance liquid chromatography-tandem mass spectrometry method, in conjunction with multiwalled carbon nanotube purification, was developed to determine the mefentrifluconazole levels in grapes, cucumbers, tomatoes, peppers, wheat, maize, eggs, milk, pork, chicken, and fish. After purification, tandem mass spectrometry of mefentrifluconazole required <3.0 min. Matrix-matched external standard curves were used to quantify the residual mefentrifluconazole. The method meets the requirements of the European Union Document SANTE/11813/2017. Quantification was linear between 5 and 500 μg/kg (R2 ≥ 0.9988), and both the intra- and interday relative standard deviations were ≤13.7%. Analyte recovery ranged from 81.5% to 107.6%. The limit of mefentrifluconazole quantification was 5 μg/kg for all matrices. The method successfully detected and quantified mefentrifluconazole that had been applied to cucumbers and tomatoes grown in a test field. These results imply that the proposed method is effective and reliable for detecting mefentrifluconazole residues in plant- and animal-derived foods. [ABSTRACT FROM AUTHOR]

Designing efficient non-precious metal catalysts for CO 2 hydrogenation is a significant challenge. Cobalt-based catalysts often failed to catalyze the reverse water-gas shift (RWGS) reaction with high CO selectivity and stability. Herein, nitrogen-doped carbon (N-C) immobilized single-atom Co-N 4 catalyst with 5% Co loading were prepared by anchoring strategy through regulating the cobalt species coordination structure. The stable single-atom catalyst achieves almost 100% CO selectivity and a high CO 2 conversion of 52.4% at 500 °C during CO 2 hydrogenation, while the 20% Co-N-C nanoparticle catalyst favored CH 4 formation. The experiments and density functional theory (DFT) calculations revealed that atomically dispersed Co-N 4 site followed the hydrogen-assisted pathway in which the intermediate COOH* was desorbed and dissociated into CO, whereas the Co nanoparticle catalysts mainly followed the direct dissociation. This study provided a new strategy for designing Co-based RWGS catalysts with excellent performance. [Display omitted] • The single-atom Co-N 4 catalyst with 5% Co loading is successfully synthesized through the anchoring strategy. • The stable single-atom catalyst achieves almost 100% CO selectivity and high conversion of 52.4% at 500 °C during CO 2 hydrogenation. • This work provided a new strategy for designing Co-based RWGS catalysts with excellent performance. [ABSTRACT FROM AUTHOR]

• A fluorescent sensor based on S-CQDs was constructed to detect pirimicarb. • A green deep eutectic solvent was synthesized to extract pirimicarb. • S-CQDs had vast negative charges as the fluorescence probe. • Electrostatic interactions led to fluorescence quenching of S-CQDs. • The proposed extraction and detection strategy has prospects in food analysis. A novel deep eutectic solvent-based extraction and sulfur-doped carbon quantum dots (S-CQDs) serving as fluorescence probes to detect pirimicarb in cereals were established. The deep eutectic solvent was synthesized using choline chloride and butanediol, achieving direct and efficient extraction of pirimicarb residue in the cereals. The fluorescence quenching of S-CQDs was caused by the electrostatic interaction between the negatively charged S-CQDs and positively charged thiocholine, which was the hydrolysate of acetylthiocholine. The fluorescence of S-CQDs was enhanced as the activity of acetylcholinesterase (AChE) was inhibited by pirimicarb, achieving the detection of pirimicarb in the cereal samples. The limit of detection (LOD) was 0.006 μg mL−1. The recovery ranged from 96.6% to 108.2%. This extraction and detection method of pirimicarb based on an environmentally friendly DES and S-CQD fluorescent sensor maintains good stability and convenience, offering a promising strategy for extracting and testing harmful substances in food samples. [ABSTRACT FROM AUTHOR]

To reveal the nature of SO2 poisoning over Cu-SSZ-13 catalyst under actual exhaust conditions, the catalyst was pretreated at 200 and 500 °C in a flow containing NH3, NO, O2, SO2, and H2O. Brunner−Emmet−Teller (BET), X-ray diffraction(XRD), thermo gravimetric analyzer (TGA), ultraviolet Raman spectroscopy (UV Raman), temperature-programmed reduction with H2 (H2-TPR), temperature-programmed desorption of NO+O2 (NO+O2-TPD), NH3-TPD, in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS), and an activity test were utilized to monitor the changes of Cu-SSZ-13 before and after in situ SO2 poisoning. According to the characterization results, the types and generated amount of sulfated species were directly related to poisoning temperature. Three sulfate species, including (NH4)2SO4, CuSO4, and Al2(SO4)3, were found to form on CZ-S-200, while only the latter two sulfate species were observed over CZ-S-500. Furthermore, SO2 poisoning had a negative effect on low-temperature selective catalytic reduction (SCR) activity, which was mainly due to the sulfation of active sites, including Z2Cu, ZCuOH, and Si-O(H)-Al. In contrast, SO2 poisoning had a positive effect on high-temperature SCR activity, owing to the inhibition of the NH3 oxidation reaction. The above findings may be a useful guideline to design excellent SO2-resistant Cu-based zeolite catalysts. [ABSTRACT FROM AUTHOR]