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Methanol steam reforming (MSR) provides an alternative way for efficient production and safe transportation of hydrogen but requires harsh conditions and complicated purification processes. In this work, an efficient electrochemical‐assisted MSR reaction for pure H2 production at lower temperature (~140 °C) is developed by coupling the electrocatalysis reaction into the MSR in a polymer electrolyte membrane electrolysis reactor. By electrochemically assisted, the two critical steps including the methanol dehydrogenation and water‐gas shift reaction are accelerated, which is attributed to decreasing the methanol dehydrogenation energy and promoting the dissociation of H2O to OH* by the applied potential. Furthermore, the reduced H2 partial pressure by the hydrogen oxidation and reduction process further promotes MSR. The combination of these advantages not only efficiently decreases the MSR temperature but also achieves the high rate of hydrogen production of 505 mmol H2 g Pt−1 h−1 with exceptionally high H2 selectivity (99 %) at 180 °C and a low voltage (0.4 V), and the productivity is about 30‐fold than that of traditional MSR. This study opens up a new avenue to design novel electrolysis cells for hydrogen production. [ABSTRACT FROM AUTHOR]

Stroke has become a major disease seriously threating human health due to its high morbidity, mortality and disability. Rehabilitation nursing care for stroke patients has always been a key part of clinical care. The neurological nursing managers should pay high attention to the issue about how to more effectively improve the level of nurses’ rehabilitation nursing on stroke patients. Therefore, this paper investigates the current cognition of neurological nurses about stroke knowledge, attitude and behaviour, and then analyses the factors affecting the knowledge, attitude and behaviour of stroke in the nurses, in order to provide better nursing services for stroke patients, and improve their nursing quality. The findings show that the different cognitions of nurses about their role have different effects on the knowledge, attitudes and behavioural levels of the neurological nurses; the nurses with more types of roles have better knowledge and behavioural levels of stroke.

The scattering medium scrambles the light paths emitted from the targets into speckle patterns, leading to a significant degradation of the target image. Conventional iterative phase recovery algorithms typically yield low-quality reconstructions. On the other hand, supervised learning methods exhibit limited generalization capabilities in the context of image reconstruction. An approach is proposed for achieving high-quality reconstructed target images through scattering media using a diffusion generative model. The gradient distribution prior information of the target image is modeled using a scoring function, which is then utilized to constrain the iterative reconstruction process. The high-quality target image is generated by alternatively performing the stochastic differential equation solver and physical model-based data consistency steps. Simulation and experimental validation demonstrate that the proposed method achieves better image reconstruction quality compared to traditional methods, while ensuring generalization capabilities. [ABSTRACT FROM AUTHOR]

In this article, an uncertain disturbance rejection control problem for the affine system in the presence of asymmetric input constraints is addressed using an event‐triggered control method. The disturbance rejection control is converted to an H∞$$ {H}_{\infty } $$ optimal control problem, and a zero‐sum game‐based method is proposed to solve this H∞$$ {H}_{\infty } $$ optimal control problem. To deal with the input constraints, a new cost function is proposed. The event‐triggered controller is updated only when the triggering condition is satisfied, which can reduce the computational complexity.In order to obtain a controller that minimizes the performance index function in the worst‐case disturbance, we use a critic‐only network to solve the Hamilton–Jacobi–Isaacs (HJI) equation, and the critic network weight is tuned through a gradient descent method with the historical state data. The stability of the closed‐loop system and the uniform ultimate boundedness of the critic network parameters are proved by the Lyapunov method. Two numerical examples are provided to verify the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

High‐temperature proton exchange membrane fuel cells (HT‐PEMFCs) are crucial in future energy systems. However, the activity and stability of the electrocatalysts are severely restricted by high temperature and phosphoric acid poisoning. Herein, PtCe alloy as oxygen reduction reaction (ORR) electrocatalyst for HT‐PEMFCs exhibits fantastic performance. Ce can increase the electronic density of Pt, weakening phosphoric acid poisoning and improving ORR activity. The optimized electronic structure can also reduce the dipole effect between Pt and O, which suppresses the irreversible oxidation of Pt. Additionally, the dramatically negative heat of formation in PtCe catalyst brings high kinetic barrier of metal diffusion and dissolution. With this electrocatalyst, the HT‐PEMFCs show a preeminent peak power of 605 mW cm−2 with 0.3 mgPt cm−2. After 30000 cycles of accelerated stability test, the peak power density only decreases by 31.6%, achieving the goal of Department of Energy in 2020 (<40% loss). [ABSTRACT FROM AUTHOR]

To explore the effect of amine chain length on CO2 absorption performance, the reaction kinetics of CO2 absorption in aqueous 1‐dimethylamino‐2‐propanol (DMA2P), 1‐diethylamino‐2‐propanol (DEA2P), 2‐(methylamino)ethanol (MAE), and 2‐(ethylamino)ethanol (EAE) solutions with different concentrations were explored using the stopped‐flow apparatus. Additionally, Density Functional Theory (DFT) calculations were conducted to examine the reaction mechanism and the free energy barrier of the elementary reactions underlying CO2 absorption in these four aqueous amine solutions. Kinetic models for CO2 absorption in tertiary amines and secondary amines were established, based on the base‐catalyzed hydration mechanism and the zwitterion mechanism, respectively, both of which perform well in predicting the relationship between k0 and the amine concentration. The free energy barrier obtained by DFT is consistent with the activation energy barrier trend obtained by experiment. In addition, the effect of chain length on the free energy barrier was investigated through the chemical bond and weak interaction analysis. [ABSTRACT FROM AUTHOR]

The durability degradation during stack‐operating conditions seriously deteriorates the lifetime and performance of the fuel cell. To alleviate the rapid potential rise and performance degradation, an anode design is proposed to match the working temperature of high‐temperature proton exchange membrane fuel cells (HT‐PEMFCs) with the release temperature of hydrogen from palladium. The result is significantly enhanced hydrogen oxidation reaction (HOR) activity of Pd and superior performance of the Pd anode. Furthermore, Pd as hydrogen buffer and oxygen absorbent layer in the anode can provide additional in situ hydrogen and absorb infiltrated oxygen during local fuel starvation to maintain HOR and suppress reverse‐current degradation. Compared with the traditional Pt/C anode, the Pd/C also greatly improved HT‐PEMFCs durability during start‐up/shut‐down and current mutation. The storage/release of hydrogen provides innovative guidance for improving the durability of PEMFCs. [ABSTRACT FROM AUTHOR]