Operation optimization of auxiliary electric boiler system in HTR-PM nuclear power plant

Du Xingxuan,Ma Xiaolong,Liu Junfeng,Wu Shifa,Wang Pengfei 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.8

Electric boilers (EBs) are the backup steam source for the auxiliary steam system of high-temperature gas-cooled reactor nuclear power plants. When the plant is in normal operations, the EB is always in hot standby status. However, the current hot standby operation strategy has problems of slow response, high power consumption, and long operation time. To solve these problems, this study focuses on the optimization of hot standby operations for the EB system. First, mathematical models of an electrode immersion EB and its accompanying deaerator were established. Then, a control simulation platform of the EB system was developed in MATLAB/Simulink implementing the established mathematical models and corresponding control systems. Finally, two optimization strategies for the EB hot standby operation were proposed, followed by dynamic simulations of the EB system transient from hot standby to normal operations. The results indicate that the proposed optimization strategies can significantly speed up the transient response of the EB system from hot standby to normal operations and reduce the power consumption in hot standby operations, improving the dynamic performance and economy of the system.

Long non-coding RNAs in Sus scrofa ileum under starvation stress

Wang Shu,Ma Yi Jia,Li Yong Shi,Ge Xu Sheng,Lu Chang,Cai Chunbo,Yang Yang,Zhao Yan,Liang Guo Ming,Guo Xiaohong,Cao Guoqing,Li Bugao,Gao Pengfei 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.7

Objective: In this study, we aimed to identify long non-coding RNAs (lncRNAs) that play important roles in starvation stress, analyze their functions, and discover potential molecular targets to alleviate starvation stress to provide a theoretical reference for subsequent in-depth research. Methods: We generated a piglet starvation stress animal model. Nine Yorkshire weaned piglets were randomly divided into a long-term starvation stress group (starved for 72 h), short-term starvation stress group (starved for 48 h), and the control group. LncRNA libraries were constructed using high-throughput sequencing of piglet ileums. Results: We obtained 11,792 lncRNAs, among which, 2,500 lncRNAs were novel. In total, 509 differentially expressed (DE)lncRNAs were identified in this study. Target genes of DElncRNAs were predicted via cis and trans interactions, and functional and pathway analyses were performed. Gene ontology functions and Kyoto encyclopedia of genes and genomes analysis revealed that lncRNA-targeted genes mainly participated in metabolic pathways, cellular processes, immune system processes, digestive systems, and transport activities. To reveal the mechanism underlying starvation stress, the interaction network between lncRNAs and their targets was constructed based on 26 DElncRNAs and 72 DEmRNAs. We performed an interaction network analysis of 121 DElncRNA–DEmRNA pairs with a Pearson correlation coefficient greater than 0.99. Conclusion: We found that MSTRG.19894.13, MSTRG.16726.3, and MSTRG.12176.1 might play important roles in starvation stress. This study not only generated a library of enriched lncRNAs in piglets, but its outcomes also provide a strong foundation to screen key lncRNAs involved in starvation stress and a reference for subsequent in-depth research. Objective: In this study, we aimed to identify long non-coding RNAs (lncRNAs) that play important roles in starvation stress, analyze their functions, and discover potential molecular targets to alleviate starvation stress to provide a theoretical reference for subsequent in-depth research.Methods: We generated a piglet starvation stress animal model. Nine Yorkshire weaned piglets were randomly divided into a long-term starvation stress group (starved for 72 h), short-term starvation stress group (starved for 48 h), and the control group. LncRNA libraries were constructed using high-throughput sequencing of piglet ileums.Results: We obtained 11,792 lncRNAs, among which, 2,500 lncRNAs were novel. In total, 509 differentially expressed (DE)lncRNAs were identified in this study. Target genes of DElncRNAs were predicted via cis and trans interactions, and functional and pathway analyses were performed. Gene ontology functions and Kyoto encyclopedia of genes and genomes analysis revealed that lncRNA-targeted genes mainly participated in metabolic pathways, cellular processes, immune system processes, digestive systems, and transport activities. To reveal the mechanism underlying starvation stress, the interaction network between lncRNAs and their targets was constructed based on 26 DElncRNAs and 72 DEmRNAs. We performed an interaction network analysis of 121 DElncRNA–DEmRNA pairs with a Pearson correlation coefficient greater than 0.99.Conclusion: We found that MSTRG.19894.13, MSTRG.16726.3, and MSTRG.12176.1 might play important roles in starvation stress. This study not only generated a library of enriched lncRNAs in piglets, but its outcomes also provide a strong foundation to screen key lncRNAs involved in starvation stress and a reference for subsequent in-depth research.

H∞ Exponential Synchronization of Switched Cellular Neural Networks Based on Disturbance Observer-based Control

Linlin Hou,Pengfei Ma,Xuan Ma,Haibin Sun 제어·로봇·시스템학회 2024 International Journal of Control, Automation, and Vol.22 No.4

The problem of H∞ exponential synchronization for switched cellular neural networks that are subjected to multiple exogenous disturbances is investigated. The exogenous disturbances are rejected and attenuated by combining disturbance observer-based control with H∞ control. Based on the admissible edge-dependent average dwell time scheme and the Lyapunov-Krasovskii functional technique, a synchronization criterion formulated by linear matrix inequalities is procured for switched cellular neural networks with external disturbances. Finally, the effectiveness of the obtained results is verified through a numerical simulation.

Ginsenoside Rd alleviates mouse acute renal ischemia/reperfusion injury by modulating macrophage phenotype

Ren, Kaixi,Jin, Chao,Ma, Pengfei,Ren, Qinyou,Jia, Zhansheng,Zhu, Daocheng The Korean Society of Ginseng 2016 Journal of Ginseng Research Vol.40 No.2

Background: Ginsenoside Rd (GSRd), a main component of the root of Panax ginseng, exhibits anti-inflammation functions and decreases infarct size in many injuries and ischemia diseases such as focal cerebral ischemia. M1 Macrophages are regarded as one of the key inflammatory cells having functions for disease progression. Methods: To investigate the effect of GSRd on renal ischemia/reperfusion injury (IRI) and macrophage functional status, and their regulatory role on mouse polarized macrophages in vitro, GSRd (10-100 mg/kg) and vehicle were applied to mice 30 min before renal IRI modeling. Renal functions were reflected by blood serum creatinine and blood urea nitrogen level and histopathological examination. M1 polarized macrophages infiltration was identified by flow cytometry analysis and immunofluorescence staining with $CD11b^+$, $iNOS^+$/interleukin-12/tumor necrosis factor-${\alpha}$ labeling. For the in vitro study, GSRd ($10-100{\mu}g/mL$) and vehicle were added in the culture medium of M1 macrophages to assess their regulatory function on polarization phenotype. Results: In vivo data showed a protective role of GSRd at 50 mg/kg on Day 3. Serum level of serum creatinine and blood urea nitrogen significantly dropped compared with other groups. Reduced renal tissue damage and M1 macrophage infiltration showed on hematoxylin-eosin staining and flow cytometry and immunofluorescence staining confirmed this improvement. With GSRd administration, in vitro cultured M1 macrophages secreted less inflammatory cytokines such as interleukin-12 and tumor necrosis factor-${\alpha}$. Furthermore, macrophage polarization-related pancake-like morphology gradually changed along with increasing concentration of GSRd in the medium. Conclusion: These findings demonstrate that GSRd possess a protective function against renal ischemia/reperfusion injury via downregulating M1 macrophage polarization.

Preparation and properties of polymeric surfactants: A potential corrosion inhibitor of carbon steel in acidic medium

Bin Lyu,Huihui Liu,Pengfei Li,Dangge Gao,Jianzhong Ma 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.80 No.-

The polymeric surfactants were synthesized using allyl glycidyl ether, acrylamide, butyl acrylate andsodium allylsulfonate by radical polymerization and applied as corrosion inhibitor of carbon steel viaweight loss method. The structure of polymeric surfactants was confirmed by FT-IR and NMR. The surfaceactivity of polymeric surfactants was characterized by surface tension and wetting power. Theanticorrosion mechanism of polymeric surfactants was confirmed by anticorrosion efficiency, the Gibbsadsorption free energy, SEM, AFM and XPS. The experimental results show that with the increase of theamount of polymeric surfactants, the corrosion resistance efficiency increases gradually, which provesthat it is an effective corrosion inhibitor. The preparation process of the polymeric surface activity issimple which can be used for industrial production.

Transient Stability Simulation Analysis of Multi Node Power Network with Variable Speed Pumped Storage Units

Zhao Chong,Wang Longze,Ma Yiyi,Xiang Pengfei,Jiang Siyu,Chen Weidong,Zhang Yan,Li Meicheng 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.4

The output characteristics of variable speed pumped storage are different from conventional hydropower and constant speed pumped storage units. The continuous increase of installed capacity of variable speed pumped storage, poses a severe challenge to the safe and stable operation of the local power grid. Proposed in this paper is a kind suitable for multi-node containing variable speed pump machine storage unit electric power network transient stability method, considering the variable speed pumped storage units by the end of the instantaneous failure prone to sudden drop transient power, the power network with more nodes each busbar voltage stable operation as the goal, according to the regional power grid data under typical operation modes, Based on the power system analysis software package, an electromechanical simulation model of the 7-node power grid with variable speed pumped storage unit was established. The influence on the transient stability of a 7-node power grid is analyzed by removing variable speed pumped-storage units and three-phase short-circuit faults. The transient stability of the power grid can be maintained under the conditions of removing variable speed pumped-storage units and three-phase short-circuit faults, but some bus voltages are higher than the specified voltage upper limit. The reactive power compensation device is installed to improve the voltage stability of the power grid system, which can prevent the overvoltage accident caused by the fault of the communication system, achieve the purpose of multi-node power network stability, and improve the safety and stability of the regional power system when the fault occurs.

Ginsenoside Rd alleviates mouse acute renal ischemia/reperfusion injury by modulating macrophage phenotype

Kaixi Ren,Chao Jin,Pengfei Ma,Qinyou Ren,Zhansheng Jia,Daocheng Zhu 고려인삼학회 2016 Journal of Ginseng Research Vol.40 No.2

Background: Ginsenoside Rd (GSRd), a main component of the root of Panax ginseng, exhibits antiinflammation functions and decreases infarct size in many injuries and ischemia diseases such as focal cerebral ischemia. M1 Macrophages are regarded as one of the key inflammatory cells having functions for disease progression. Methods: To investigate the effect of GSRd on renal ischemia/reperfusion injury (IRI) and macrophage functional status, and their regulatory role on mouse polarized macrophages in vitro, GSRd (10e100 mg/ kg) and vehicle were applied to mice 30 min before renal IRI modeling. Renal functions were reflected by blood serum creatinine and blood urea nitrogen level and histopathological examination. M1 polarized macrophages infiltration was identified by flow cytometry analysis and immunofluorescence staining with CD11bþ, iNOSþ/interleukin-12/tumor necrosis factor-a labeling. For the in vitro study, GSRd (10 e100 mg/mL) and vehicle were added in the culture medium of M1 macrophages to assess their regulatory function on polarization phenotype. Results: In vivo data showed a protective role of GSRd at 50 mg/kg on Day 3. Serum level of serum creatinine and blood urea nitrogen significantly dropped compared with other groups. Reduced renal tissue damage and M1 macrophage infiltration showed on hematoxylineeosin staining and flow cytometry and immunofluorescence staining confirmed this improvement. With GSRd administration, in vitro cultured M1 macrophages secreted less inflammatory cytokines such as interleukin-12 and tumor necrosis factor-a. Furthermore, macrophage polarization-related pancake-like morphology gradually changed along with increasing concentration of GSRd in the medium. Conclusion: These findings demonstrate that GSRd possess a protective function against renal ischemia/ reperfusion injury via downregulating M1 macrophage polarization.

Effect of ages and season temperatures on bi-surface shear behavior of HESUHPC-NSC composite

Yang Zhang,Yanping Zhu,Pengfei Ma,Shuilong He,Xudong Shao Techno-Press 2023 Advances in concrete construction Vol.15 No.6

Ultra-high-performance concrete (UHPC) has become an attractive cast-in-place repairing material for existing engineering structures. The present study aims to investigate age-dependent high-early-strength UHPC (HESUHPC) material properties (i.e., compressive strength, elastic modulus, flexural strength, and tensile strength) as well as interfacial shear properties of HESUHPC-normal strength concrete (NSC) composites cured at different season temperatures (i.e., summer, autumn, and winter). The typical temperatures were kept for at least seven days in different seasons from weather forecasting to guarantee an approximately consistent curing and testing condition (i.e., temperature and relative humidity) for specimens at different ages. The HESUHPC material properties are tested through standardized testing methods, and the interfacial bond performance is tested through a bi-surface shear testing method. The test results quantify the positive development of HESUHPC material properties at the early age, and the increasing amplitude decreases from summer to winter. Three-day mechanical properties in winter (with the lowest curing temperature) still gain more than 60% of the 28-day mechanical properties, and the impact of season temperatures becomes small at the later age. The HESUHPC shrinkage mainly occurs at the early age, and the final shrinkage value is not significant. The HESUHPC-NSC interface exhibits sound shear performance, the interface in most specimens does not fail, and most interfacial shear strengths are higher than the NSC-NSC composite. The HESUHPC-NSC composites at the shear failure do not exhibit a large relative slip and present a significant brittleness at the failure. The typical failures are characterized by thin-layer NSC debonding near the interface, and NSC pure shear failure. Two load-slip development patterns, and two types of main crack location are identified for the HESUHPC-NSC composites tested in different ages and seasons. In addition, shear capacity of the HESUHPC-NSC composite develops rapidly at the early age, and the increasing amplitude decreases as the season temperature decreases. This study will promote the HESUHPC application in practical engineering as a cast-in-place repairing material subjected to different natural environments.

Recent Advances in the Synthesis of Carbon-based Materials from Biomass for the Oxygen Evolution Reaction (OER) by Hydrothermal Method

Xu ZENG,Guodong YAO,Jianglin CAO,Pengfei GUO,Cuixiang MA,Jianfu ZHAO 대한환경공학회 2019 대한환경공학회 학술발표논문집 Vol.2019 No.-

Comparative study on two finite element models for multi-clamp pipeline system

Yiming Cao,Qingdong Chai,Xumin Guo,Hui Ma,Pengfei Wang 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.3

Due to the limitations of space and environment, a considerable number pipelines supported by multiple clamps are used in the external pipeline system of aero engines, which lead to the modeling difficulties and low efficiency. In this paper, taking U-shaped and Zshaped pipelines as examples, two methods of whole modeling and section modeling are used based on the finite element, and the piecewise linear models of clamps are introduced to compare the vibration characteristics under different boundary conditions. In addition, the simulation results are compared and verified by experiments. In the modal analysis, the coupled modes refer to the dependent modes which can influence each other through energy transfer while independent modes without energy transfer are called un-coupled modes. The results show that, for uncoupled modes of U-shaped and Z-shaped pipeline systems, the section model has smaller error and higher efficiency, which is suitable for the primary design stage of complex multi-clamp pipeline system. For the order of coupled mode, the accuracy of the whole model is high, and it is suitable for the check and vibration analysis of pipeline system. Moreover, the errors of both models decrease with the increase of tightening torque.