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Flame retardants endow epoxy resins (EP) with flame retardance, however, their introduction often lead to the decrease in the glass transition temperature (Tg), which is an important property for EP. Therefore, it is significant to design and synthesize a high‐efficiency flame retardant that enhances flame retardance and Tg of EP. To achieve this goal, a hyperbranched polyamide oligomer containing DOPO (HPD) was successfully synthesized by A4 + B2 polymerization and its structure was confirmed by FTIR, 1H NMR, and 30P NMR spectra and GPC. HPD was used as an additive flame retardant in epoxy resin, and its effect on the flame retardance and thermal properties of epoxy resin was studied. The epoxy resin with 7.5 wt% HPD reached UL‐94V‐0 rating and a higher LOI value of 29.6%, and its Tg was 176.2°C, which is higher than the pure epoxy resin. Moreover, the results of cone calorimetry testing (CCT) and TG‐FTIR analysis suggested that the gas‐phase and condensed‐phase flame‐retarded roles of HPD delayed the time to ignition, and reduced the value of relevant combustion parameters, including the peak of heat release rate, average of heat release rate, total heat release, smoke production rate, and total smoke production. The analysis results of Py‐GC/MS test of HPD further confirmed that HPD was able to play the flame‐retarded role in the gaseous and condensed phases. [ABSTRACT FROM AUTHOR]

The hydrophilic nanometer titanium dioxide (TiO2) was surface modified using (3-aminopropyl) triethoxy-silane. The structure of the modified TiO2 was characterized by FTIR and TG. The flame-retardant epoxy resins were prepared based on the mixture of a fixed amount of 5, 10-dihydro-phenophosphazine-10-oxide (DPPA) and different amounts of the modified TiO2. And their flame-retardant, mechanical and thermal properties were studied. The results indicated that TiO2 was successfully modified by APTS. The mixture of 2.5wt% DPPA and 0.05wt% modified TiO2 gave epoxy resin UL-94 V-0 rating and a LOI value of 28.8%. The tensile and flexural strengths of the flame-retardant epoxy resin were 86.52, 116.75 MPa, respectively, both higher than those of epoxy resin without flame retardant. Moreover, its T5% and Tg were as high as 364.3 and 162.0 °C, respectively. The prepared flame-retardant epoxy resin possessed good comprehensive properties. [ABSTRACT FROM AUTHOR]

To protect above‐ground plant organs from excessive water loss, their surfaces are coated by waxes. The genes involved in wax formation have been investigated in detail in Arabidopsis but scarcely in crop species. Here, we aimed to isolate and characterize a CER1 enzyme responsible for formation of the very long‐chain alkanes present in high concentrations especially during late stages of wheat development. On the basis of comparative wax and transcriptome analyses of various wheat organs, we selected TaCER1‐1A as a primary candidate and demonstrated that it was located to the endoplasmic reticulum, the subcellular compartment for wax biosynthesis. A wheat nullisomic‐tetrasomic substitution line lacking TaCER1‐1A had significantly reduced amounts of C33 alkane, whereas rice plants overexpressing TaCER1‐1A showed substantial increases of C25–C33 alkanes relative to wild type control. Similarly, heterologous expression of TaCER1‐1A in Arabidopsis wild type and the cer1 mutant resulted in increased levels of unbranched alkanes, iso‐branched alkanes and alkenes. Finally, the expression of TaCER1‐1A was found activated by abiotic stresses and abscisic acid treatment, resulting in increased production of alkanes in wheat. Taken together, our results demonstrate that TaCER1‐1A plays an important role in wheat wax alkane biosynthesis and involved in responding to drought and other environmental stresses. In this paper, the function of TaCER1‐1A involved in wheat alkane biosynthesis was tested using gain‐of‐function (transgenic plants) and loss‐of‐function plants (gene deletion wheat line), and the role of alkanes in drought resistance was assessed. [ABSTRACT FROM AUTHOR]

DOPO-based sodium salt (DOPO-ONa) was successfully synthesized from 9, 10-dihydro-9-oxa-0-phosphorphenanthrene-10-oxide (DOPO), aqueous hydrogen peroxide solution and anhydrous sodium carbonate. Then, DOPO-based sodium salt functionalized LDH (R-D-LDH) was successfully prepared by the high temperature roasting of LDH, DOPO-ONa- modification and reconstruction in water, and its structure was characterized by XRD, UV-Vis and TG. The epoxy resins containing R-D-LDH was prepared, and its flame-retardant and thermal properties were studied by using UL-94 vertical burning, LOI, cone calorimeter, TG and DSC. The results indicated that the flame-retardant efficiency of LDH was improved after functionalization by DOPO-based sodium salt. Compared with the epoxy resins containing LDH, the epoxy resins containing R-D-LDH showed the reduced burning degree and had the higher LOI values. The combustion intensity and smoke production of epoxy resin were decreased by the incorporation of R-D-LDH. When 6 wt% R-D-LDH was introduced into epoxy resin, the LOI value of epoxy resin was increased from 23.7% to 24.6%. And during combustion, its PHRR, THR and THR were decreased by 211 kW/m °C, 13 MJ/m² and 1 229 m²/m², respectively, and its increase range of the residue was 58%. Moreover, its Tgwas 160.6 °C, which was same as the pure epoxy resin, and its T5% was as high as 365.7 °C. [ABSTRACT FROM AUTHOR]

As the integration of renewable energy expands, effective energy system management becomes increasingly crucial. Distributed renewable generation microgrids offer green energy and resilience. Combining them with energy storage and a suitable energy management system (EMS) is essential due to the variability in renewable energy generation. Reinforcement learning (RL)-based EMSs have shown promising results in handling these complexities. However, concerns about policy robustness arise with the growing number of grid intermittent disruptions or disconnections from the main utility. This study investigates the resilience of RL-based EMSs to unforeseen grid disconnections when trained in grid-connected scenarios. Specifically, we evaluate the resilience of policies derived from advantage actor–critic (A2C) and proximal policy optimization (PPO) networks trained in both grid-connected and uncertain grid-connectivity scenarios. Stochastic models, incorporating solar energy and load uncertainties and utilizing real-world data, are employed in the simulation. Our findings indicate that grid-trained PPO and A2C excel in cost coverage, with PPO performing better. However, in isolated or uncertain connectivity scenarios, the demand coverage performance hierarchy shifts. The disruption-trained A2C model achieves the best demand coverage when islanded, whereas the grid-connected A2C network performs best in an uncertain grid connectivity scenario. This study enhances the understanding of the resilience of RL-based solutions using varied training methods and provides an analysis of the EMS policies generated. [ABSTRACT FROM AUTHOR]

• Catalytic ozonation method has higher efficiency at lower temperature. • CuMn-II attains an EA conversion of 99% at 120 °C with an O 3 /EA molar ratio of 10. • Abundant oxygen vacancies contribute to the superior performance of CuMn-II. • In-situ DRIFTS and DFT calculations are combined to evaluate the reaction mechanism. A series of Cu-Mn oxides were synthesized by the redox-precipitation method with different precipitants to evaluate the catalytic ozonation of ethyl acetate (EA). It was found that CuMn-II (with H 2 C 2 O 4 as precipitant) exhibited the best catalytic activity, which achieved an EA conversion of 99 % at 120 °C with an O 3 /EA molar ratio of 10. The reaction temperature, O 3 /EA molar ratio, ozone utilization rate, and CO x selectivity were also discussed. Meanwhile, many characterizations were conducted to reveal the properties of catalysts, such as SEM, XRD, BET, XPS, H 2 -TPR and NH 3 -TPD. Abundant surface defects, plentiful oxygen vacancies, larger specific surface area, higher content of Mn3+ and more acid sites contributed to the superior performance of CuMn-II. Catalyst poisoning occurred when SO 2 was added, however, the conversion of EA could gradually recover to 88 % once SO 2 was stopped. In-situ DRIFTS measurement was carried out to reveal the formation of intermediate species during the reaction. Combined with DFT calculations, a reaction mechanism for the catalytic ozonation of EA over CuMn 2 O 4 catalysts was proposed. [ABSTRACT FROM AUTHOR]

Oxygen reduction reaction (ORR) is a crucial reaction for various energy conversion and storage devices, but the sluggish kinetics and the usage of noble metals greatly restrict its practical device applications. In this work, a well-designed high-performance catalyst for ORR was synthesized via a facile one-step Co-MOF carbonization method, in which Co-MOF was prepared using the cobalt acetate tetrahydrate and 2,2′-bipyridyl-5,5′-dicarboxylic acid (H2bpydc) as the only raw materials and H2bpydc as the favorable carbon and nitrogen source for in situ nitrogen doping and metallic cobalt reduction. The resultant 3D mesoporous carbon foam catalyst with embedded Co nanoparticles (CoN-CF) is enriched with nitrogen, which exhibits high specific surface area and abundant N-doping active sites for catalytic ORR. In particular, the optimized CoN-CF-700 sample displays the best catalytic performances including onset potential of 0.94 V, half-wave potential of 0.85 V, long-term durability and superior resistance to methanol poisoning. The demonstrated synthetic strategy provides a new insight into easy-synthesis and high-economy routes for metal-N-C catalysts and a deeper understanding of the effects of microstructures on catalytic mechanisms. [ABSTRACT FROM AUTHOR]