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In order to solve the problem where the traditional intelligent inspection robot only has a single inspection function, we studied the use of a dry powder (including an ultra-fine dry powder) as a fire-extinguishing medium for the first time. In fire-extinguishing robots, the spray pressure is difficult to control, and there are several other issues. For integrated inspection, an intelligent, nitrogen-driven fire-extinguishing robot using a dry powder in a pressure-controlled spray was developed. On this basis, in order to investigate nitrogen-driven dry powder particle spraying as a gas–solid two-phase mechanism, as well as the flow characteristics and the influence of relevant parameters on the spraying effect, a nitrogen-driven dry powder particle spraying system was established as part of a gas–solid two-phase computational fluid dynamics model. The flow field of the spraying system and the particle motion characteristics were analyzed to explore the micro-mechanisms of the influence of different driving pressures, pipe diameters, and nozzle configurations on the spraying of the dry powder. In order to investigate the macroscopic effect of dry powder spraying where the gas–solid two-phase micro-mechanisms could not be revealed, an experimental platform was set up, and the experiments verified the accuracy of the numerical simulation results. We also investigated the dry powder spraying effect under different driving pressures, pipe diameters, nozzle configurations, and loading ratios. Finally, an orthogonal test was designed based on the results of the single-factor experiments to find the best combination of parameters required to achieve the optimal spraying effect. The research results can provide a theoretical and technical reference for the design and development of nitrogen-driven dry powder spraying systems. [ABSTRACT FROM AUTHOR]

Due to the particularity of raw materials and the complexity of processes, the petroleum and petrochemical industry involves a variety of disaster risks in production, transportation, storage and etc. However, there are three barriers in the emergency rescue of the petroleum and petrochemical industry, scene separation, data isolation and inefficient coordination. No matter the application of existing technology or the proposed method and concept, the situation cannot be broken quickly. By analyzing these problems existing in 5G communication technology, artificial intelligence and petroleum and petrochemical emergency rescue, this paper puts forward the concept of petroleum and petrochemical remote collaborative emergency technology, analyzes the development trend of remote collaborative emergency technology, and prospects the petroleum and petrochemical emergency rescue technology.

AB line and C line of Trans-Asia natural gas pipeline has attained a gas transmission capacity as 55 billion cubic meters per year. In recent years, pipeline transportation throughput accounts for about 20% of Chinese apparent consumption of natural gas. In order to ensure an economic and efficient operation of this transnational pipeline system, this paper conducts a comprehensive study on the joint operation of AB line and C line of Uzbekistan section of Trans-Asia natural gas pipeline. This paper innovatively puts forward “Methods of correction on multi-pressure head and multi-performance curve of centrifugal compressor”, aka. Data difference adjustment method”, to correct the factory performance curve of compressor, to ensure that the simulation accuracy is higher than 95%, and to provide support for operation decision-making. Based on the principle of minimum energy consumption of AB line and C line system of Trans-Asian natural gas pipeline, a set of optimal air intake allocation scheme between AB and C lines is studied and integration method of process operation scheme of AB line and C line are studied to support the optimum operation. Pipeline joint operation method for different hydraulic systems is studied. The pressure control principle by pressure balance method which realizes the joint operation of pipelines from different hydraulic systems is suggested for the first time, by which the pipeline operates stably. This paper studies the best location of 8 bridges reservations in AB line and C line in Uzbekistan, in order to enhance the comprehensively allocation capability of the whole system of transnational pipeline network in an all-round way, and to realize the function of energy conservation under normal conditions and of throughput guarantee under abnormal conditions. With additional bridges, pipeline transportation capacity can be increased up to 26 million m3/day and save energy consumption by up to 660 thousand m3/day under accident conditions. Keywords: Natural gas pipeline, Joint operation, Transmission allocation principle, Energy consumption

The article discusses a new suture method called the multi-gradient buried vertical mattress suture, which is used to close high-tension wounds. The method involves three buried vertical mattress sutures and an intradermal suture to reduce tension on wound edges and scar hyperplasia. However, the method does have the drawback of increased skin pigmentation and scarring at puncture points. The article provides a detailed description of the operative procedure and presents a typical case study to demonstrate the effectiveness of the suture method in reducing skin tension and improving aesthetic outcomes. [Extracted from the article]

Background: The tumor microenvironment in hepatocellular carcinoma (HCC) is complicated. Tumor-infiltrating T and B cells play a pivotal role in anti-tumor immunity. T cell receptor (TCR) and B cell receptor (BCR) features may reflect the disease-associated antigen response., Methods: By combining bulk TCR/BCR-sequencing, RNA-sequencing, whole exome-sequencing, and human leukocyte antigen-sequencing, we examined the immune repertoire (IR) features of tumor and adjacent non-tumor tissues obtained from 64 HCC patients., Results: High IR heterogeneity with weak similarity was discovered between tumor and non-tumor tissues. Higher BCR diversity, richness, and somatic hypermutation (SHM) were found in non-tumor tissues, while TCRα and TCRβ diversity and richness were comparable or higher in tumor. Additionally, lower immune infiltration was found in tumor than non-tumor tissues; the microenvironment in tumor appeared to keep stably inhibited and changed slightly with tumor progression. Moreover, BCR SHM was stronger, whereas TCR/BCR diversity declined with HCC progression. Importantly, we found that higher IR evenness in tumor and lower TCR richness in non-tumor tissues indicated better survival in HCC patients. Collectively, the results revealed that TCR and BCR exhibited distinct features in tumor and non-tumor tissues., Conclusions: We demonstrated that IR features vary between different tissues of HCC. IR features may represent a biomarker for the diagnosis and treatment of HCC patients, providing references for subsequent immunotherapy research and strategy selection., Competing Interests: Author LT was employed by HRYZ Biotech Co., Shenzhen, China. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Xie, Yan, Zheng, Shi, Tang, Li, Liu, Gan, Wang, Jiang, Liu, Wu and Wang.)