Deep mining is an inevitable tendency in the development of coal industry. There are many heat damage problems with the increase of mining depth. The technology of using doublet wells, together with Heat Exchange Mach...Deep mining is an inevitable tendency in the development of coal industry. There are many heat damage problems with the increase of mining depth. The technology of using doublet wells, together with Heat Exchange Machine Systems (HEMSs), to store cold energy is a key to solve the heat damage problems in deep mines. Based on the geological conditions, thermodynamic and hydraulic parameters of Jiahe Mine, the isotherms in the period of cold energy storage and refrigeration and the volumes of cold water within different temperature ranges of the cold energy storage well were numerically analyzed. The results show that 1) with the same pumped and injected water volumes, the lower the temperature of injected water is, the larger the volume of cold water in the cold energy storage well is. With the larger volume, the effect of cold energy storage is better. 2) the larger the volumes of pumped and reinjected water are, the larger the volume of cold water from the cold energy storage well is. With the larger volume, the effect of refrigeration is better. And 3) without disturbance, the volume and temperature of cold water in the cold energy storage well can keep unchanged or have only a little change for a long time. Therefore the technology of doublet wells for cold energy storage is feasible and the cold energy storage aquifers can meet the requirement of the technology.展开更多
We studied the dynamic fracture mechanical behavior of rock under different impact rates. The fracture experiment was a three-point bending beam subjected to different impact loads monitored using the reflected causti...We studied the dynamic fracture mechanical behavior of rock under different impact rates. The fracture experiment was a three-point bending beam subjected to different impact loads monitored using the reflected caustics method. The mechanical parameters for fracture of the three-point bending beam specimen under impact load are analyzed. The mechanism of crack propagation is discussed. Experimental results show that the dynamic stress intensity factor increases before crack initiation. When the dynamic stress intensity factor reaches its maximum value the crack starts to develop. After crack initiation the dynamic stress intensity factor decreases rapidly and oscillates. As the impact rate increases the cracks initiate earlier, the maximum value of crack growth velocity becomes smaller and the values of dynamic stress intensity factor also vary less during crack propagation. The results provide a theoretical basis for the study of rock dynamic fracture.展开更多
基金supported by grants from the Youth Innovative Talents Program and Characteristic Innovative Talents Program of Regular Institutions of Higher Education of Guangdong Province(2018KQNCX212,2020KTSCX101)the Scientific Research Project of Traditional Chinese Medicine Bureau of Guangdong Province(20222122)+3 种基金the Excellent Youth Science Research Program of the Education Department of Hunan Province(14B183)Bureau of Education of Guangzhou Municipality(202032801)the Plan on Enhancing Scientific Research in Guangzhou Medical Universitythe Open Research Funds(2021)and the Funds of Selected Project(2022)from GMU-GIBH Joint School of Life Sciences,Guangzhou Medical University。
文摘目的oxLDL可上调Plin2的表达,进而促进泡沫细胞的形成,LOX1是oxLDL的受体。本文探讨Plin2与LOX1在动脉粥样硬化发生发展过程中的关系。方法从GEO数据库中下载GSE43292,分析Plin2、LOX1的表达及Plin2、LOX1与NF-κB信号通路的相关性。采用oxLDL处理的RAW264.7细胞作为动脉粥样硬化的细胞模型进行研究,蛋白质免疫印迹法检测细胞中Plin2、LOX1和p-p65的表达,荧光中性脂质染料BODIPY 493/503染色法检测细胞内脂滴。结果通过分析GSE43292数据发现,Plin2、LOX1在颈动脉粥样硬化斑块中的表达显著高于颈动脉邻近组织。oxLDL处理RAW264.7细胞24 h后,Plin2与LOX1的表达、细胞内脂滴明显增加。过表达Plin2的细胞中LOX1表达升高;当用oxLDL孵育过表达Plin2的细胞后,LOX1的水平升高更为显著;但在没有oxLDL处理的情况下,敲减Plin2对细胞内LOX1的表达没有影响。基因集富集分析(gene set enrichment analysis,GSEA)结果显示,在动脉粥样硬化中,Plin2和LOX1的表达与NF-κB的活化呈正相关。此外,尽管采用oxLDL处理细胞,NF-κB抑制剂JSH-23预处理仍可显著降低Plin2与LOX1的表达、细胞内的脂质积聚,过表达Plin2后,JSH-23亦能显著抑制oxLDL孵育的细胞中Plin2和LOX1的表达。结论Plin2可通过上调LOX1的表达促进细胞内脂质积聚,参与动脉粥样硬化,这一过程至少部分是通过激活NF-κB通路实现的。
基金Project 50490270 supported by Key Project of National Natural Science Foundation of China
文摘Deep mining is an inevitable tendency in the development of coal industry. There are many heat damage problems with the increase of mining depth. The technology of using doublet wells, together with Heat Exchange Machine Systems (HEMSs), to store cold energy is a key to solve the heat damage problems in deep mines. Based on the geological conditions, thermodynamic and hydraulic parameters of Jiahe Mine, the isotherms in the period of cold energy storage and refrigeration and the volumes of cold water within different temperature ranges of the cold energy storage well were numerically analyzed. The results show that 1) with the same pumped and injected water volumes, the lower the temperature of injected water is, the larger the volume of cold water in the cold energy storage well is. With the larger volume, the effect of cold energy storage is better. 2) the larger the volumes of pumped and reinjected water are, the larger the volume of cold water from the cold energy storage well is. With the larger volume, the effect of refrigeration is better. And 3) without disturbance, the volume and temperature of cold water in the cold energy storage well can keep unchanged or have only a little change for a long time. Therefore the technology of doublet wells for cold energy storage is feasible and the cold energy storage aquifers can meet the requirement of the technology.
基金the support of the National Natural Science Foundation of China (Grant No.50774086 and 50874109)
文摘We studied the dynamic fracture mechanical behavior of rock under different impact rates. The fracture experiment was a three-point bending beam subjected to different impact loads monitored using the reflected caustics method. The mechanical parameters for fracture of the three-point bending beam specimen under impact load are analyzed. The mechanism of crack propagation is discussed. Experimental results show that the dynamic stress intensity factor increases before crack initiation. When the dynamic stress intensity factor reaches its maximum value the crack starts to develop. After crack initiation the dynamic stress intensity factor decreases rapidly and oscillates. As the impact rate increases the cracks initiate earlier, the maximum value of crack growth velocity becomes smaller and the values of dynamic stress intensity factor also vary less during crack propagation. The results provide a theoretical basis for the study of rock dynamic fracture.
