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The conversion of methane into high-value-added liquid chemicals such as methanol is an ideal means of carbon resource storage and recycling. However, the intricate catalytic steps and the presence of diverse reactive oxygen species (•OH and •O2–, etc.) obscure the oxygen sources and reaction pathways of the product C1 oxygenates. In particular, the frequent coexistence of CH3OOH and CH3OH in liquid products further complicates the matter. In this study, two distinct types of Au/TiO2 nanoparticle catalysts, i.e., one with nonselective deposition and another with selective deposition, were synthesized via chemical reduction and photodeposition, respectively. On this basis, we systematically investigated their photocatalytic performances in methane oxidation and successfully established the structure–activity relationship between the crystal surface and product selectivity. Mechanistic studies revealed that the {001} and {101} facets of TiO2 nanocrystals played dominant roles in the generation of CH3OH and CH3OOH primary oxygenates, respectively, due to their varying abilities to further convert •O2–. In addition, Au, serving as an electron acceptor, facilitates the reduction of oxygen to form •O2– and promotes facet-related reactions. These findings offered a great perspective for the development of methane photooxidation to produce liquid oxygenates. [ABSTRACT FROM AUTHOR]

Compared to normal traditional Chinese timber buildings, citygate buildings are relatively high, lightweight, and quite vulnerable to wind. The present work aims to carry out a wind-induced vibration study on a traditional Chinese citygate building, the Nanjing Drum Tower, with the method of computational fluid dynamics (CFD) simulation to determine the wind loads and finite element (FE) analysis to assess its structural response. The architectural and structural characteristics of traditional Chinese timber buildings in the Ming-Qing dynasties are analysed. The Nanjing Drum Tower has typical characteristics and is taken as the representative building in this study. The wind pressure coefficients of the drum tower are obtained by CFD simulation with the Reynolds-averaged Navier-Stokes (RANS) model. The structural response of the drum tower under wind loads is analysed based on FE analysis. The obtained results can provide a basis for assessing the wind-induced vibration of traditional Chinese citygate buildings. [ABSTRACT FROM AUTHOR]

Ancient Chinese stone arch bridges are an important kind of architectural heritage in China, and they are often threatened by potential collapse problems. The stone arrangements of the arches in ancient Chinese stone arch bridges are quite different from those in Western countries, which may lead to different collapse modes. Thus, the collapse mechanisms of arches with typical "Chinese stone arrangements" urgently need to be studied. In this paper, the stone arrangements commonly used in ancient Chinese stone arch bridges were first investigated and summarized in detail. Then, finite element models of four typical arches with different stone arrangements were established to study their mortar failure processes, collapse modes, and bearing capacities. After that, the influence of the friction coefficients of the voussoirs on the collapse modes and the bearing capacities of these typical arches was analyzed. The results show that the stone arrangements used in ancient Chinese stone arch bridges can generally be divided into three groups according to their lateral linkages. The bearing capacities of the four typical arches are sorted as follows when the friction coefficient is 0.3: the FJBL method > the HLFJBL method > the HL method > the BL method. When the friction coefficient decreases from 0.3 to 0.1, the live-load bearing capacities of these arches decrease by 33%–55%. When the friction coefficient increases from 0.3 to ∞, the live-load bearing capacities of these arches increase by 3%–11%. The study results can provide a scientific basis for the conservation of ancient Chinese stone bridges. [ABSTRACT FROM AUTHOR]

In order to study structural properties of Dingtougong mortise-tenon joints of Chinese traditional hall-style timber buildings built in the Song and Yuan dynasties, and to provide theoretical basis for structural analysis and scientific conservation of this type of architectural heritages. First, the main structural characteristics of the Chinese hall-style timber buildings built in the Song and Yuan dynasties were sorted out, including the structural forms, structural dimensions, and configurations of mortise-tenon joints. Then, the low cyclic loading tests of the six reduced-scale mortise-tenon joints were carried out, including the five groups of Dingtougong mortise-tenon joints, and the one reference group of mortise-tenon joint without Dingtougong. The results show that all the five groups of Dingtougong mortise-tenon joints have better structural performance than the one reference group of mortise-tenon joint on the aspects of ultimate capacity and rotational rigidity. In the five groups of Dingtougong mortise-tenon joints, the structural performance of the Dingtougong mortise-tenon joint with Dingtougong of through mortise-tenon joint is obviously superior to that of the Dingtougong mortise-tenon joint with Dingtougong of half mortise-tenon joint. Besides, considering material nonlinearity and contact nonlinearity, the finite element models of the six groups of mortise-tenon joints were built up by ANSYS, and the structural properties of these mortise-tenon joints under in-plane vertical load, out-of-plane horizontal load and torque load were analyzed and compared with the experimental results. The theoretical results very coincide with the experimental results. Under in-plane vertical load, the Dingtougong obviously improves the mechanical performance of the mortise-tenon joint. In addition, the relationships among the initial elastic rotational rigidity KY under in-plane vertical load, the initial elastic rotational rigidity KX under out-of-plane horizontal load, and the initial elastic rotational rigidity KR under torque load of these six groups of mortise-tenon joints were obtained, the results of which can provide theoretical base for structural analysis and conservation design of Chinese traditional hall-style timber buildings. [ABSTRACT FROM AUTHOR]

In the fast-paced world of product design, businesses seek a competitive edge by swiftly addressing user requirements and developing precise solutions. Depending on diverse knowledge, conceptual design makes enterprises invest significantly in knowledge management. Following the philosophy of decision-based design, a knowledge graph-aided decision guidance method is proposed to streamline and enhance knowledge utilisation in product conceptual design. Firstly, the decision-making process in product conceptual design is modelled using the Concept-Decision-Knowledge (CDK) model, yielding the meta-model of CDK (mCDK). A data-augmented BERT-BiLSTM-CRF model is adopted to extract information from diverse data sources, forming a CDK knowledge graph (CDK-KG). A decision case for employing problem-solving knowledge configuration is generated to resolve specific design decision problems when new requirements arise. Validation of the method is demonstrated through a case study on the launch vehicle conceptual design of the first and second-stage separation system. The results indicate that the proposed method can automatically extract information from data resources to construct a knowledge graph. Furthermore, it can provide decision cases for design requirements through knowledge configuration, supporting decision-making. [ABSTRACT FROM AUTHOR]

Background: The prescription of Chinese herbal medicine (CHM) consists of multiple herbs that exhibit synergistic effects due to the presence of multiple components targeting various pathways. In clinical practice, the combination of Erchen decoction and Huiyanzhuyu decoction (EHD) has shown promising outcomes in treating patients with laryngeal squamous cell carcinoma (LSCC). However, the underlying mechanism by which EHD exerts its therapeutic effects in LSCC remains unknown., Methods: Online databases were utilized for the analysis and prediction of the active constituents, targets, and key pathways associated with EHD in the treatment of LSCC. The protein-protein interaction (PPI) network of common targets was constructed and visualized using Cytoscape 3.8.1 software. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to investigate the functional roles of core targets within the PPI network. Protein clustering was conducted utilizing the MCODE plug-in. The obtained results highlight the principal targets and pathways involved. Subsequently, clinical samples were collected to validate alterations in the levels of these main targets through Western blotting (WB) and immunohistochemistry (IHC). Furthermore, both in vivo and in vitro experiments were conducted to investigate the therapeutic effects of EHD on healing LSCC and elucidate its underlying mechanism. Additionally, to ensure experimental reliability and reproducibility, quality control measures utilizing HPLC were implemented for EHD herbal medicine., Results: The retrieval and analysis of databases in EHD medicine and LSCC disease yielded a total of 116 overlapping targets. The MCODE plug-in methods were utilized to acquire 8 distinct protein clusters through protein clustering. The findings indicated that both the first and second clusters exhibited a size greater than 6 scores, with key genes PI3K and ErbB occupying central positions, while the third and fourth clusters were associated with proteins in the PI3K, STAT3, and Foxo pathways. GO functional analysis reported that these targets had associations mainly with the pathway of p53 mediated DNA damage and negative regulation of cell cycle in terms of biological function; the death-induced signaling complex in terms of cell function; transcription factor binding and protein kinase activity in terms of molecular function. The KEGG enrichment analysis demonstrated that these targets were correlated with several signaling pathways, including PI3K-Akt, FoxO, and ErbB2 signaling pathway. On one hand, we observed higher levels of key genes such as P-STAT3 , P-PDK1 , P-Akt , PI3K , and ErbB2 in LSCC tumor tissues compared to adjacent tissues. Conversely, FOXO3a expression was lower in LSCC tumor tissues. On the other hand, the key genes mentioned above were also highly expressed in both LSCC xenograft nude mice tumors and LSCC cell lines, while FOXO3a was underexpressed. In LSCC xenograft nude mice models, EHD treatment resulted in downregulation of P-STAT3, P-PDK1, PI3K, P-AKT, and ErbB2 protein levels but upregulated FOXO3a protein level. EHD also affected the levels of P-STAT3, P-PDK1, PI3K, P-AKT, FOXO3a, and ErbB2 proteins in vitro: it inhibited P-STAT3, P-AKT, and ErbB2, while promoting FOXO3a; however, it had no effect on PDK1 protein. In addition, HPLC identified twelve compounds accounting for more than 30% within EHD. The findings from this study can serve as valuable guidance for future experimental investigations., Conclusion: The possible mechanism of EHD medicine action on LSCC disease is speculated to be closely associated with the ErbB2/PI3K/AKT/FOXO3a signaling pathway., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.