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Considering the substantial role of ammonia, developing highly efficient electrocatalysts for nitrate‐to‐ammonia conversion has attracted increasing interest. Herein, we proposed a feasible strategy of p–d orbital hybridization via doping p‐block metals in an Ag host, which drastically promotes the performance of nitrate adsorption and disassociation. Typically, a Sn‐doped Ag catalyst (SnAg) delivers a maximum Faradaic efficiency (FE) of 95.5±1.85 % for NH3 at −0.4 V vs. RHE and reaches the highest NH3 yield rate to 482.3±14.1 mg h−1 mgcat.−1. In a flow cell, the SnAg catalyst achieves a FE of 90.2 % at an ampere‐level current density of 1.1 A cm−2 with an NH3 yield of 78.6 mg h−1 cm−2, during which NH3 can be further extracted to prepare struvite as high‐quality fertilizer. A mechanistic study reveals that a strong p–d orbital hybridization effect in SnAg is beneficial for nitrite deoxygenation, a rate‐determining step for NH3 synthesis, which as a general principle, can be further extended to Bi‐ and In‐doped Ag catalysts. Moreover, when integrated into a Zn‐nitrate battery, such a SnAg cathode contributes to a superior energy density of 639 Wh L−1, high power density of 18.1 mW cm−2, and continuous NH3 production. [ABSTRACT FROM AUTHOR]

Amorphous materials are distinguished by their exceptional attributes, notably their expansive surface area and the profusion of active sites they present. Consequently, the amorphization process stands as an efficacious strategy to augment the catalytic efficacy of electrocatalysts. This is achieved through the meticulous construction of the surface architecture and the precise modulation of the electronic configuration of these materials. Therefore, this review aims to offer a thorough examination of the latest progress in the application of amorphous materials for the enhancement of electrocatalytic processes, with a particular emphasis on the nitrate (NO3−) reduction reaction (NITRR) and the carbon dioxide reduction reaction (CO2RR). Initially, we delve into the structural benefits inherent to amorphous materials, outlining the diverse synthesis techniques and characterization methodologies utilized in their development. Following this, we illustrate the utilization of various amorphous materials in NITRR and CO2RR, accentuating how the amorphous framework influences electrocatalytic activities. Concludingly, we encapsulate the merits and the obstacles encountered in the application of amorphous electrocatalysts for NITRR and CO2RR, whilst also forecasting the future direction for the creation of innovative amorphous electrocatalysts. [ABSTRACT FROM AUTHOR]

As a renewable energy source, solar energy has attracted more and more attention because of its growing energy demand and the huge potential of greenhouse gas emissions. However, the intermittent and stochastic nature of the solar itself limited the conversion and storage efficiency of solar energy. In recent years, the latent heat storage system based on solid-liquid phase change energy storage materials has expected to become a suitable way to improve solar absorption and conversion due to high-storage density and excellent chemical stability. Nevertheless, the solid-liquid phase change energy storage materials are often limited in practical applications by their own phase separation, low heat transfer rates, subcooling, leakage in the molten state and unstable properties. One of the solutions is to combine porous carriers with solid-liquid phase change energy storage materials to produce porous fixed phase change energy storage materials. An introduction is provided to the energy storage mechanism and heat transfer enhancement mechanism of phase change energy storage materials. The effects of porous carrier materials types, preparation methods on the porous shaped phase change energy storage materials, and its potential applications are systematically analyzed. [ABSTRACT FROM AUTHOR]

Urea synthesis from abundant CO2 and N‐feedstocks via renewable electricity has attracted increasing interests, offering a promising alternative to the industrial‐applied Haber‐Meiser process. However, the studies toward electrochemical urea production remain scarce and appeal for more research. Herein, in this perspective, an up‐to‐date overview on the urea electrosynthesis is highlighted and summarized. Firstly, the reaction pathways of urea formation through various feedstocks are comprehensively discussed. Then, we focus on the strategies of materials design to improve C−N coupling efficiency by identifying the descriptor and understanding the reaction mechanism. Finally, the current challenges and disadvantages in this field are reviewed and some future development directions of electrocatalytic urea synthesis are also prospected. This Minireview aims to promote future investigations of the electrochemical urea synthesis. [ABSTRACT FROM AUTHOR]

The uniaxial tensile loading test set-up and rapid chloride ion migration (RCM) method are combined effectively in this study, and the chloride diffusivity coefficient of recycled aggregate concrete (RAC) under uniaxial tensile stress is investigated. Test results show that the uniaxial tensile loading has a significant effect on RAC chloride diffusivity coefficient, and the chloride diffusivity coefficient firstly increases slowly and then increases sharply as the tensile stress ratio increases. In addition, the change trend of the RAC chloride diffusivity coefficient in dependence on the tensile stress ratio is different from that on the compressive stress ratio. The RAC chloride diffusivity coefficient is more sensitive to tensile stress. Based on the experimental data, a relationship between RAC chloride diffusivity coefficient and uniaxial tensile stress is established. [ABSTRACT FROM AUTHOR]

Long-term electrocardiogram (ECG) recording can reveal some vital cardiovascular disorders and provide warning of human sudden cerebral or vascular diseases in advance. This requires high-quality ECG skin electrodes. Gel (Ag/AgCl) electrodes were reported to have good signal quality in ECG acquisition, but easily caused human skin irritation or allergy. Consequently, textile electrodes have attracted more attention for long-term ECG acquisition. In this paper, eight woven fabrics with diverse yarns and weft densities were fabricated in plain and honeycomb structures. The fabrics were investigated in terms of comfortability, fabric–skin contact impedance and acquired bio-signal quality. Honeycomb weave electrodes were measured with a high comfort level from subjective and objective views, including pleasant tactile comfort, high visual acceptance, good air permeability and good heat transfer. Weave electrodes made of all conductive filaments in high density had low skin contact impedance and high-quality ECG signals. An increase of compression load on weave electrodes resulted in a decrease of contact impedance with a high signal quality. A conductive honeycomb weave with unit repeat of 6*6 warps*wefts presented the highest score of acquired ECG signals of all studied electrodes based on the qualities of the QRS complex, P and T waves, R peak amplitude and variation and signal-to-noise ratio. This study contributes to the future design and fabrication of textile electrodes using honeycomb weave in long-term and real-time collection of human ECGs. [ABSTRACT FROM AUTHOR]

In this work, a fast water-responsive shape memory hybrid polymer based on thermoplastic polyurethane (TPU) was prepared by crosslinking with hydroxyethyl cotton cellulose nanofibers (CNF-C) and multi-walled carbon nanotubes (CNTs). The effect of CNTs content on the electrical conductivity of TPU/CNF-C/CNTs nanocomposite was investigated for the feasibility of being a strain sensor. In order to know its durability, the mechanical and water-responsive shape memory effects were studied comprehensively. The results indicated good mechanical properties and sensing performance for the TPU matrix fully crosslinked with CNF-C and CNTs. The water-induced shape fixity ratio (Rf) and shape recovery ratio (Rr) were 49.65% and 76.64%, respectively, indicating that the deformed composite was able to recover its original shape under a stimulus. The TPU/CNF-C/CNTs samples under their fixed and recovered shapes were tested to investigate their sensing properties, such as periodicity, frequency, and repeatability of the sensor spline under different loadings. Results indicated that the hybrid composite can sense large strains accurately for more than 103 times and water-induced shape recovery can to some extent maintain the sensing accuracy after material fatigue. With such good properties, we envisage that this kind of composite may play a significant role in developing new generations of water-responsive sensors or actuators. [ABSTRACT FROM AUTHOR]

Objective: Obstructive Sleep Apnea-Hypopnea Syndrome (OSAHS) and Laryngopharyngeal Reflux Disease (LPRD) are interrelated medical conditions affecting the respiratory system. This article aimed to investigate the potential correlation between the two., Methods: This cross-sectional study was carried out on a total of 52 participants diagnosed with both OSAHS and LPRD. Clinical data of baseline demographics of year, sex, BMI, including clinical indicators such as AHI (Apnea Hypopnea Index), OSAHS severity grading, RFS (Reflux Finding Score), RSI (Reflux Symptom Index), and 24-hour pH level were collected. Statistical analysis was then conducted to evaluate the correlation between OSAHS and LPRD., Results: Among the 52 patients, the the average age was 43.3±11.6 years with a mean 24.7±2.9 kg/m2 BMI level. The mean duration of OSAHS was 4.1±1.7 years with mean 38.7±12 AHI scores and 30.8% mild OSAHS, 51.9% moderate OSAHS, and 17.3% severe OSAHS. Mean LPRD duration was 3.2±1.5 years with a mean 15.9±4.9 RFS score, mean 28.0±6.8 RSI score, and mean 3.9±0.8 24-hour pH level. There was a strong positive correlation between AHI scores and both the RFS score (r>0.9, P < .01) and RSI score (r>0.9, P < .01). While a strong negative correlation between AHI scores and 24-hour pH level was observed (r < -0.8, P < .01). And there was a strong positive correlation between OSAHS severity levels and both the RSF score (r>0.8, P < .01) and RSI score (r>0.79, P < .01). While a significant negative correlation between OSAHS severity and 24-hour pH level was detected (r < -0.7, P < .01)., Conclusions: The findings of this cross-sectional study demonstrate a strong positive correlation between the severity of OSAHS, as indicated by AHI scores, and the severity of LPRD, as measured by RFS and RSI scores. A negative correlation was also observed between AHI scores and 24-hour pH level, indicating a connection between these two medical conditions.

Electrocatalytic C-N coupling between NO 3 - and CO 2 has emerged as a sustainable route for urea production. However, identifying catalytic active sites and designing efficient electrocatalysts remain significant challenges. Herein, the synthesis of Cu-doped MnO 2 nanotube (denoted as Cu-MnO 2 ) with stable Cu δ+ -oxygen vacancies (O vs )-Mn 3+ dual sites is reported. Compared with pure MnO 2 , Cu δ+ doping can effectively enhance urea production performance in the co-reduction of CO 2 and NO 3 - . Thus, Cu-MnO 2 catalyst exhibits a maximum Faradaic efficiency (FE) of 54.7% and the highest yield rate of 116.7 mmol h -1  g cat. -1 in a flow cell. Remarkably, the urea yield rate remains over 78 mmol h -1  g cat. -1 across a wide potential range. Further experimental and theoretical results elucidate the unique role of Cu-MnO 2 solid-solution for stabilizing Cu δ+ sites in Cu δ+ -O vs -Mn 3+ , endowing the catalyst with superior structural and electrochemical stabilities. This thermodynamically promotes urea formation and kinetically lowers the energy barrier of C-N coupling., (© 2024 Wiley‐VCH GmbH.)

Alkali ions, major components at the electrode-electrolyte interface, are crucial to modulating reaction activity and selectivity of catalyst materials. However, the underlying mechanism of how the alkali ions catalyze the N 2 reduction reaction (NRR) into ammonia remains elusive, posing challenges for experimentalists to select appropriate electrolyte solutions. In this work, by employing a combined experimental and computational approach, we proposed four essential roles of cation ions at Fe electrodes for N 2 fixation: (i) promoting NN bond cleavage; (ii) stabilizing NRR intermediates; (iii) suppressing the competing hydrogen evolution reaction (HER); and (iv) modulating the interfacial charge distribution at the electrode-electrolyte interface. For N 2 adsorption on an Fe electrode with cation ions, our constrained ab initio molecular dynamic (c-AIMD) results demonstrate a barrierless process, while an extra 0.52 eV barrier requires to be overcome to adsorb N 2 for the pure Fe-water interface. For the formation of *NNH species within the N 2 reduction process, the calculated free energy barrier is 0.50 eV at the Li + -Fe-water interface. However, the calculated barrier reaches 0.81 eV in pure Fe-water interface. Furthermore, experiments demonstrate a high Faradaic efficiency for ammonia synthesis on a Li + -Fe-water interface, reaching 27.93% at a working potential of -0.3 V vs RHE and pH = 6.8. These results emphasize how alkali metal cations and local reaction environments on the electrode surface play crucial roles in influencing the kinetics of interfacial reactions.

The quest for sustainable urea production has directed attention toward electrocatalytic methods that bypass the energy-intensive traditional Haber-Bosch process. This study introduces an approach to urea synthesis through the coreduction of CO 2 and NO 3 - using copper-doped molybdenum diselenide (Cu-MoSe 2 ) with Cu-Mo dual sites as electrocatalysts. The electrocatalytic activity of the Cu-MoSe 2 electrode is characterized by a urea yield rate of 1235 μg h -1 mg cat. -1 at -0.7 V versus the reversible hydrogen electrode and a maximum Faradaic efficiency of 23.43% at -0.6 V versus RHE. Besides, a continuous urea production with an enhanced average yield rate of 9145 μg h -1 mg cat. -1 can be achieved in a flow cell. These figures represent a substantial advancement over that of the baseline MoSe 2 electrode. Density functional theory (DFT) calculations elucidate that Cu doping accelerates *NO 2 deoxygenation and significantly decreases the energy barriers for C-N bond formation. Consequently, Cu-MoSe 2 demonstrates a more favorable pathway for urea production, enhancing both the efficiency and feasibility of the process. This study offers valuable insights into electrode design and understanding of the facilitated electrochemical pathways.

The electrochemical NO 3 - reduction and its coupling with CO 2 can provide novel and clean routes to synthesize NH 3 and urea, respectively. However, their practical application is still impeded by the lack of efficient catalysts with desirable Faradaic efficiency (FE) and yield rate. Herein, we report the synthesis of molybdenum oxide nanoclusters anchored on carbon black (MoO x /C) as electrocatalyst. It affords an outstanding FE of 98.14 % and NH 3 yield rate of 91.63 mg h -1  mg cat. -1 in NO 3 - reduction. Besides, the highest FE of 27.7 % with a maximum urea yield rate of 1431.5 μg h -1  mg cat. -1 toward urea is also achieved. The formation of electron-rich MoO x nanoclusters with highly unsaturated metal sites in the MoO x /C heterostructure is beneficial for enhanced catalytic performance. Studies on the mechanism reveal that the stabilization of *NO and *CO 2 NOOH intermediates are critical for the NH 3 and urea synthesis, respectively., (© 2023 Wiley-VCH GmbH.)