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The electrochemical NH3 synthesis on TiNO is proposed to follow the Mars–van Krevelen (MvK) mechanism, offering more favorable N2 adsorption and activation on the N vacancy (Nv) site, compared to the conventional associative mechanism. The regeneration cycle of Nv represents the rate-determining step in this process. This study investigates a series of TM (Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, and Pt)–TiNO to explore the *H migration (from TM to TiNO)-promoted Nv cycle. The screening results indicate that Ni–TiNO exhibits strong H2O decomposition for *H production with 0.242 eV and low *H migration resistance with 0.913 eV. Notably, *H migration from Ni to TiNO significantly reduces the Nv formation energy to 0.811 eV, compared to 1.387 eV on pure TiNO. Meanwhile, in the presence of *H, Nv formation takes precedence over Tiv and Ov. Lastly, electronic performance calculations reveal that the collaborative function provided by Ni and Nv enables highly stable and efficient NH3 synthesis. The *H migration-assisted MvK mechanism demonstrates effective catalytic cycle performance in electrochemical N2 fixation and may have potential applicability to other hydrogenation reactions utilizing water as a proton source. [ABSTRACT FROM AUTHOR]

Objective : To investigate the effect and mechaniSm of epigallocatechin gallate (EGCG) on inteStinal injury in Sepsis rats. Methods: 332 Male SD rats were randomly divided into Sham group (Sham group), sepsis group (CLP group), sepsis + EGCG group (EGCG group) and sepsis + GSK2606414 intervention group (GSK group), with 8 rats in each group. In Sham group, only the cecum was observed and the abdomen was closed immediately after laparotomy. Caecal ligation and perforation were performed in CLP group. EGCG group was intraperitoneally injected 50 mg/kg of EGCG after CLP. The GSK group was given 100 mg/kg of GSK2606414 per day for one week before CLP. The 4 groups of rats were killed 24 h after the modeling, and serum and intestinal tissue samples were collected and preserved. The pathological changes of intestinal tract in rats were observed by hematoxylin-eosin staining. enzyme-linked immunosorbent assays was used to detect the levels of IL-1 and IL-6 in serum of rats. The positive area percentage of phosphorylated protein kinase R-like endoplasmic reticulum kinase (p-PERK), CCAAT enhancer binding protein homologous protein (CHOP), aspartate-specific cysteine proteinase-12 (Caspase-12) and Claudin-1 (Clau-din-1) in intestinal tissue was observed by immunohistochemistry. The expressions of p-PERK, R-like endoplasmic reticulum kinase (PERK), CHOP, Caspase-12 and Claudin-1 in rat intestinal tissues were detected by Western blotting. Results: The intestinal villi structure of CLP group was seriously damaged, and a large number of inflammatory cells could be seen under the microscope. The pathological injury of EGCG and GSK groups was less than that of CLP group, and the Chiu's score of CLP group was significantly higher than that of EGCG and GSK group (P<0.05). Serum levels of IL-1 and IL-6 in CLP group were significantly higher than those in Sham group, and serum levels of inflammatory factors in EGCG group and GSK group were significantly lower than those in CLP group (P<0.05). The percentage of positive area of P-PERK, CHOP and Caspase-12 in the intestinal tissue of rats in CLP group was significantly higher than that in Sham group, while the percentage of positive area in EGCG group and GSK group was significantly lower than that in CLP group (P<0.05). The percentage of Claudin-1 positive area in intestinal tissue of rats in CLP group was significantly lower than that in Sham group, and the percentage of positive area in intestinal tissue of rats in EGCG group and GSK group was significantly higher than that in CLP group (P<0.05). The expression levels of P-PERK, CHOP and Caspase-12 in the intestinal tissues of rats in CLP group were higher than those in Sham group, and the above levels in EGCG and GSK groups were lower than those in CLP group (P<0.05). The expression level of Claudin-1 protein in the intestinal tissues of CLP group was lower than that of Sham group, and the above indexes in EGCG and GSK groups were higher than those in CLP group (P<0.05). Conclusion: Epigallocatechin gallate has certain therapeutic effect on intestinal injury in sepsis, and its mechanism may be related to the inhibition of endoplasmic reticulum stress (ERS) apoptotic pathway. [ABSTRACT FROM AUTHOR]

The Gestalt theory of mental completeness in architecture gave rise to the ideas of "positive space" and "negative space". This research digs into the sturdy structural building process of bamboo architecture, which is essentially distinguished by "negative space". It examines how bamboo is articulated in architectural space, while attempting to establish a balance between form and structure, with the goal of discovering the current value and spiritual position that bamboo in architecture represents. Using the Phu Quoc Island Visitor Center in Vietnam as an example, we introduce the strong structure concept and examine its design process in terms of spatial operation technique and strong structural expression logic. The fundamental strategy for creating bamboo architecture under this concept is to take the lead in negative space design and use the material capabilities of bamboo to build structural space prototypes. This further encourages the use of green building materials and offers architects working with bamboo a reference. [ABSTRACT FROM AUTHOR]

The Volmer step in alkaline hydrogen evolution reactions (HERs), which supplies H* to the following steps by cleaving H–O–H bonds, is considered the rate-determining step of the overall reaction. The Volmer step involves water dissociation and adsorbed hydroxyl (*OH) desorption; Ru-based catalysts display a compelling water dissociation process in an alkaline HER. Unfortunately, the strong affinity of Ru for *OH blocks the active sites, resulting in unsatisfactory performance during HER processes. Hence, this study investigates a series of key descriptors (ΔG*H2O, ΔG*H–OH, ΔG*H, and ΔG*OH) of TM (Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, or Pt)–Ru/Mo2Ti2C3O2 to systematically explore the effects of bimetallic site interactions on the kinetics of the Volmer step. The results indicate that bimetallic catalysts effectively reduced the strong adsorption of *OH on Ru sites; especially, the NiRu diatomic state shows the highest electron-donating ability, which promoted the smooth migration of *OH from Ru sites to Ni sites. Therefore, Ru, Ni and MXenes are suitable to serve as water adsorption and dissociation sites, *OH desorption sites, and H2 release sites, respectively. Ultimately, NiRu/Mo2Ti2C3O2 promotes Volmer kinetics and has the potential to improve alkaline HERs. This work provides theoretical support for the construction of synergistic MXene-based diatomic catalysts and their wide application in the field of alkaline HERs. [ABSTRACT FROM AUTHOR]

To date, MoS2 can only be achieved at microscale. Edge pinning effect caused by structure defects is the most obvious barrier to expand the size of structural superlubricity to macroscale. Herein, we plan to pin edge planes of MoS2 with nanospheres, and then the incommensurate structure can be formed between adjacent rolling nanoparticles to reduce friction. The sputtered MoS2 film was prepared by the physical vapor deposition (PVD) in advance. Then enough Cu2O nanospheres (∼40 nm) were generated in situ at the edge plane of MoS2 layers by liquid phase synthesis. An incommensurate structure (mismatch angle (θ) = 8°) caused by MoS2 layers was formed before friction. The friction coefficient of the films (5 N, 1,000 r/min) was ∼6.0×10−3 at the most. During friction, MoS2 layers pinned on numerous of Cu2O nanoparticles reduced its edge pinning effect and decreased friction. Moreover, much more incommensurate was formed, developing macro-superlubricity. [ABSTRACT FROM AUTHOR]

Multigas detection is in demand for a wide range of environmental and industrial applications. In this work, a sensitive and selective multigas photoacoustic spectroscopy (MG‐PAS) sensor was developed by employing a nonresonant photoacoustic spectroscopy technique combining a broadband radiation source. Six gases including CO, CO2, CH4, C2H2, C2H4, and C2H6 were selected as target measurement molecules. Selectivity of the MG‐PAS was realized by using six mid‐infrared narrow‐band filters which integrated in a homemade filter wheel. A minimum concentration detection limits of 0.2 ppm for CO, 0.05 ppm for CO2, 0.12 ppm for CH4, 0.1 ppm for C2H2, 0.81 ppm for C2H4, and 0.05 ppm for C2H6 were obtained, respectively, with a 1‐s integration time. Measurements of six gas mixtures showed that the average measurement error of the MG‐PAS sensor was within 2%. [ABSTRACT FROM AUTHOR]