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Ammonia (NH3), a noxious gas, not merely poses a threat to human beings but also serves as a significant hydrogen carrier. The matter related to its emission is naturally highly deserving of people’s meticulous attention and in-depth research. Taking into account the substantial harm that ammonia inflicts upon the environment and the human body, the storage of ammonia is indisputably an inevitable aspect in the course of green development. Simultaneously, ammonia finds extensive applications and serves as an indispensable raw material for numerous fertilizers, food, explosives, and even medicines. When employed as a fuel, ammonia boasts numerous advantages, rendering it a widely utilized and highly promising gas. Therefore, the storage of ammonia is extremely worthy of profound exploration. Currently, the principal ammonia treatment technologies comprise adsorption, absorption, catalytic conversion, biological treatment, and plasma treatment. The research and development of adsorption materials constitutes the crucial link in ammonia gas adsorption, and the storage materials for ammonia are also highly diverse. This paper integrates a considerable number of various literatures and experiments from multiple perspectives to furnish a comprehensive summary of the current research and achievements in ammonia adsorption and desorption. The materials involved mainly consist of some metal chlorides, metal oxides, zeolites, and MOF materials. Metal chlorides are highly prone to forming amide complexes with ammonia. Metal oxides are a type of compounds composed of metal elements and oxygen elements, which are typically highly stable in nature and have wide-ranging applications in various fields. Research on the utilization of metal oxides as ammonia adsorbents has consistently been a focus for scholars in different countries. The microporous structure of zeolite is extremely well-developed, which results in an exceptionally high specific surface area. This high specific surface area provides a considerable amount of contact space for molecules, thereby significantly enhancing the adsorption efficiency of the adsorbent. [ABSTRACT FROM AUTHOR]

Photocatalysts like TiO2 can harness sunlight to reduce CO2 into valuable hydrocarbon fuels, representing a promising solution for carbon neutrality and sustainable energy challenges. Herein, the effect of hydrothermal modification on the CO2 photothermal reduction activity of TiO2 catalyst was studied, through photo-catalytic performance test, XRD, Raman, N2 adsorption, SEM, TEM, CO2-TPD, UV-vis DRS, and PL on commercial and modified TiO2. The results show that the hydrothermal-modified TiO2-NBS is a pure anatase phase, which has a narrower band gap than the mixed anatase and rutile structure of commercial TiO2-P25, and is more favorable to the excitation of photon-generated carriers. Meanwhile, the light emission intensity of anatase phase is weaker, which is conducive to electron-hole separation, promoting the reactant intermediate conversion. In addition, compared with TiO2-P25, TiO2-NBS has better morphology and specific surface pore characteristics, more adsorption sites for CO2, and stronger adsorption strength, which facilitate the adsorption and activation reactions of CO2. As a result, TiO2-NBS exhibits stronger CO2 photothermal reduction activity, with CO and CH4 production rates of 6.49 µmol g−1 h−1 and 1.56 µmol g−1 h−1, which are 2.58 times and 2.84 times those of TiO2-P25, respectively. [ABSTRACT FROM AUTHOR]

In order to meet the increasingly stringent emission regulations for NOx in the exhaust gas of engines, selective catalytic reduction (SCR) technology is extensively studied and practiced. The key to this technology is the catalyst utilized in the chemical reactions of SCR. It is required to develop the SCR catalyst with good low-temperature performance and a wide active temperature window. A series of Cerium-based metal oxides TiCemWrO2−δ synthesized by solution combustion synthesis is studied in this paper. The SCR activity test was used to select the catalyst with the best performance. The NO conversion rate of the best catalyst in our studies reached 80% at 150 °C, kept 100% from 200 °C to 420 °C and the N2 selectivity remained above 95% for 100–500 °C. The SO2 resistance test was carried out at 250 °C and proved that our catalyst had good SO2 resistance. During the test, the NO conversion rate slightly decreased while 100 ppm SO2 was injected, but it remained above 80% for 24 h. The NO conversion rate recovered to the original value when the SO2 supply was cut off. The N2 selectivity remained at 100% throughout the process. Catalysts were characterized using BET, XRD, and SEM methods. In-situ DRIFTS method was used to study the reaction mechanism of the TiCe0.2W0.2O2−δ catalyst. It showed that the NH4+ species absorbed on the Brønsted acid played a dominant role in the SCR reactions. The bridge nitrate resulted from the NO absorption and gas phase NO was involved in the reaction. In conclusion, the mechanism studied included two routes of L-H and E-R. [ABSTRACT FROM AUTHOR]

Herein, Ag/TiO2 NH3-SCO catalyst was prepared by impregnation-rotary evaporation method with different calcination temperature and Ag loading content. The results of performance evaluation and characterization showed that the 10 wt% Ag/TiO2 catalyst calcined at 500 °C showed the best comprehensive performance, with T99 reaching 175 °C and N2 selectivity reaching 80% at high temperatures. High-temperature calcination will lead to a significant decline in catalyst activity, accompanied by the transformation of TiO2 from anatase to rutile phase and the obvious change and loss of Ag active sites, which greatly reduces the NH3 adsorption and redox ability, but it can still maintain a high N2 selectivity due to unchanged reaction mechanism. In addition, with the increase of Ag loading, excess Ag on Ag/TiO2 will form metal clusters due to the lack of sufficient anchor points, which helps to improve NH3-SCO activity. However, excessive Ag loading will reduce the specific surface area and acidic sites, and the Ag species on the catalyst surface will also change to the form of larger particles of Ag2O, which will lead to the decline of catalytic performance. [ABSTRACT FROM AUTHOR]

Supernumerary Robotic Limbs (SRLs) are designed to collaborate with the wearer, enhancing operational capabilities. When human limbs are occupied with primary tasks, controlling SRLs flexibly and naturally becomes a challenge. Existing methods such as electromyography (EMG) control and redundant limb control partially address SRL control issues. However, they still face limitations like restricted degrees of freedom and complex data requirements, which hinder their applicability in real-world scenarios. Additionally, fully autonomous control methods, while efficient, often lack the flexibility needed for complex tasks, as they do not allow for real-time user adjustments. In contrast, shared control combines machine autonomy with human input, enabling finer control and more intuitive task completion. Building on our previous work with the mouth-and-tongue interface, this paper integrates a mixed reality (MR) device to form an interactive system that enables shared control of the SRL. The system allows users to dynamically switch between voluntary and autonomous control, providing both flexibility and efficiency. A random forest model classifies 14 distinct tongue and mouth operations, mapping them to six-degree-of-freedom SRL control. In comparative experiments involving ten healthy subjects performing assembly tasks under three control modes (shared control, autonomous control, and voluntary control), shared control demonstrates a balance between machine autonomy and human input. While autonomous control offers higher task efficiency, shared control achieves greater task success rates and improves user experience by combining the advantages of both autonomous operation and voluntary control. This study validates the feasibility of shared control and highlights its advantages in providing flexible switching between autonomy and user intervention, offering new insights into SRL control.