Electrochemical techniques based on ultramicroelectrodes (UMEs) play a significant role in real-time monitoring of chemical messengers' release from single cells. Conversely, precise monitoring of cells in vitro strongly depends on the adequate construction of cellular physiological microenvironment. In this paper, we developed a multilayer microdevice which integrated high aspect ratio poly(dimethylsiloxane) (PDMS) microfluidic device for long-term automated perfusion culture of cells without shear stress and an independently addressable microelectrodes array (IAMEA) for electrochemical monitoring of the cultured cells in real time. Novel design using high aspect ratio between circular "moat" and ring-shaped micropillar array surrounding cell culture chamber combined with automated "circular-centre" and "bottom-up" perfusion model successfully provided continuous fresh medium and a stable and uniform microenvironment for cells. Two weeks automated culture of human umbilical endothelial cell line (ECV304) and neuronal differentiation of rat pheochromocytoma (PC12) cells have been realized using this device. Furthermore, the quantal release of dopamine from individual PC12 cells during their culture or propagation process was amperometrically monitored in real time. The multifunctional microdevice developed in this paper integrated cellular microenvironment construction and real-time monitoring of cells during their physiological process, and would possibly provide a versatile platform for cell-based biomedical analysis.

Life span of water cooling tuyere is one of important factors of blast furnace’s direct motion and high yield. In order to improve the life of tuyere, the flow fleld and temperature field of tuyere were simulated by using computational fluid dynamics (CFD). Simulation results show that the maximum temperature appears at the front margin of tuyere outlet side. The highest temperature of tuyere reduces significantly with the increase of water pressure below 0.4MPa. When the water pressure exceeds 0.4Pa, the highest temperature reduces slowly. In consideration of economic benefit and cooling effect, the best point of inlet pressure is 0.4MPa or so.

By the calculation of material balance, and research on the main processes of income and expenditure of chlorine in BF production , the migration principle of chlorine during BF production process can be concluded. The specific measures on how to reduce its influence in BF production are offered.