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An automatic bulk monitoring and aeration controller was programmed with an adsorption equilibrium absolute humidity (CAE)equation and was used to aerate paddy with the aim to increase moisture content (MC) and preventing fissuring. The ventilation control window for rewetting paddy was developed according to two conditions: (i) the average grain bulk temperature (tg) is higher than the dewpoint temperature (DPTa) of the atmosphere; and (ii) the equilibrium absolute humidity (EAHg) of grain moisture content plus 1 percentage point is lower than the absolute humidity (AHa) of the atmosphere. The ventilators were turned on when the atmosphere state point was within the ventilation windowand turned off outside that window. In a humid subtropical monsoon climate, during Oct. 8th to Nov. 1st, 2013, the system was used for a paddy depot of 1035 t in Dianjiang, Chongqing province. The natural humid air was introduced into the paddy bulk by negative pressure suction aeration during the 10-12 h night time period and allowed to equilibrate with grain kernels during the 12-14 h day time period. Aeration increased grain MC by 0.6 percentage points with two 1.5 kW axial flow ventilators and power consumption of 209 kW·h. The unit energy consumption was 0.336 KW·h (1% moisture·t)-1. The broken milled rice percentage was decreased by 2-3 percentage points. In the warm temperate semi-humid monsoon climate, during April 13th to June 16th, 2017, the system was used to rewet japonic paddy in a 2489 t depot in Qihe, Shandong province. The conditions for running two 0.85 kW axial flow fans were: (i) when the atmosphere relative humidity (RHa) is ≤80% and its temperature (ta) is DPTa, and EAHg80% and ta 28°C, the two fans were switched off. This rewetting aeration increased grain MC from 13.5% to 14.0%, and the unit energy consumption was 0.455 kW·h (1% moisture·t)-1. The percentages of average head rice yield and damaged grains after aeration were 71.7% and 7.7%, respectively.

Summary: As the nonlinearities of many real physical controlled systems become stronger and stronger, they are difficult to be described by accurate mathematical models. For a class of nonlinear single‐input single‐output systems with all‐state constraints and actuator faults, an event‐triggered adaptive fuzzy ABLF function fixed‐time tracking control method is proposed. The asymmetric barrier Lyapunov function (ABLF) combined with backward step technique is used to ensure the boundedness of the closed‐loop system output. In order to solve the problem of limited bandwidth resources, this paper adopts the event trigger mechanism and fuzzy control technology to approximate the unknown function to ensure the convergence of the system in a fixed time. After theoretical analysis, it is proved that the tracking error of the system converges in the small neighborhood of the origin, and it still has good tracking performance when the actuator faults. Finally, by comparing the proposed method with the asymmetric barrier Lyapunov function, which verifies the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Significant interest has emerged for the application of Pd-In2O3 catalysts as high-performance catalysts for CO2 hydrogenation to CH3OH. However, precise active site control in these catalysts and understanding their reaction mechanisms remain major challenges. In this investigation, a series of Pd-InOx catalysts were synthesized, revealing three distinct types of active sites: In-O, Pd-O(H)-In, and Pd2In3. Lower Pd loadings exhibited Pd-O(H)-In sites, while higher loadings resulted in Pd2In3 intermetallic compounds. These variations impacted catalytic performance, with Pd-O(H)-In catalysts showing heightened activity at lower temperatures due to the enhanced CO2 adsorption and H2 activation, and Pd2In3 catalysts performing better at elevated temperatures due to the further enhanced H2 activation. In situ DRIFTS studies revealed an alteration in key intermediates from *HCOO over In-O bonds to *COOH over Pd-O(H)-In and Pd2In3 sites, leading to a shift in the main reaction pathway transition and product distribution. Our findings underscore the importance of active site engineering for optimizing catalytic performance and offer valuable insights for the rational design of efficient CO2 conversion catalysts. [ABSTRACT FROM AUTHOR]

The development of high-performance electrocatalysts that rival Pt catalysts is crucial for efficiently driving the hydrogen evolution reaction (HER) to produce H2. Herein, we engineer sophisticated interfacial modulation of the Ru catalysts by constructing B, N co-doped porous carbon confined ultra-small MoC quantum dots (MoC@BNC) as an advanced catalyst carrier and stimulator. Combined experimental and theoretical calculations prove enhanced electron interaction between the Ru catalysts and the MoC quantum dots. Additionally, the B, N co-doped carbon substrate further refines the electronic structure of MoC, reinforcing the modulation of Ru catalysts. The Ru/MoC@BNC catalyst embodies a boosted H2O dissociation ability with a lowered H bonding strength, which promises an outstanding HER performance with an overpotential of 14 mV at 10 mA cm−2 in an alkaline solvent. Furthermore, robust catalytic stability is achieved with almost zero deterioration after the cycling test. This result exemplifies the importance of interfacial manipulation of the Ru catalysts to promote HER catalytic performance. [ABSTRACT FROM AUTHOR]

Precise defect engineering of metal oxide catalysts holds great importance for improving catalytic oxidation reactions. In this work, a judicious strategy by doping and partially de-doping of Cr atoms was orchestrated to produce a defect-containing Co3O4 catalyst. The co-existence of the remaining Cr dopant and some metal vacancies could synergistically contribute to the distortion of the crystal structure, Co–O bond activation, generation of abundant active oxygen species and enhancement of oxygen reactivity. Consequently, the catalytic performance for the methane oxidation reaction was significantly boosted, with a methane conversion rate normalized by the specific surface area of 0.114 μmol m−2 s−1, 1.41 times that of the pure Co3O4 catalyst at a reaction temperature of 295 °C. This work provides a viable methodology for improving Co3O4 catalysts for efficient methane oxidation. [ABSTRACT FROM AUTHOR]

Defect manipulation in metal oxide is of great importance in boosting catalytic performance for propane oxidation. Herein, a selective atom removal strategy was developed to construct a defective manganese oxide catalyst, which involved the partial etching of a Mg dopant in MnOx. The resulting MgMnOx-H catalysts exhibited superior low-temperature catalytic activity (T50 = 185 °C, T90 = 226 °C) with a propane conversion rate of 0.29 μmol·gcat.−1·h−1 for the propane oxidation reaction, which is 4.8 times that of pristine MnOx. Meanwhile, a robust hydrothermal stability was guaranteed at 250 °C for 30 h of reaction time. The comprehensive experimental characterizations revealed that the catalytic performance improvement was closely related to the defective structures including the abundant (metal and oxygen) vacancies, distorted crystals, valence imbalance, etc., which prominently weakened the Mn-O bond and stimulated the mobility of surface lattice oxygen, leading to the elevation in the intrinsic oxidation activity. This work exemplifies the significance of defect engineering for the promotion of the oxidation ability of metal oxide, which will be valuable for the further development of efficient non-noble metal catalysts for propane oxidation. [ABSTRACT FROM AUTHOR]