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According to requirement of electromagnetic compatibility in European Norm EN 301 489-1, mine-used personnel location system must pass radiation emission test when it is applied in foreign countries. For the requirement, radiation emission test for mine-used personnel location system was carried out, and causes of radiation noise was analyzed. The following rectification scheme was put forward: for the radiation emission caused by the clock signal, shorten the length of clock signal line during PCB routing, reduce the number of vias, increase the alignment width and line spacing, and laying ground wire on both sides to shield, so as to reduce return area of clock line; for different clock circuits, low-pass filter, common mode suppression and other measures were adopted to reduce radiation signal transmission. Tests results show that the maximum peak frequency power of the personnel location system after the rectification is 13.086 dB lower than requirement of EN 55032 standard CLASS A and 3.086 dB lower than the requirement of EN 55032 standard CLASS B, which can meet the export requirements.

According to the needs of wireless communication of working face of coal mine, the paper analyzed advantages and disadvantages of existing wired and wireless communication technologies used in working face, proposed a design scheme of full coverage wireless communication system of working face of coal mine based on WMN and ZigBee technology, and introduced designs of comprehensive base station and WiFi gateway. The test results show that the system can meet the needs of wireless transmission of different information of data, voice, video, so as to achieve full coverage of wireless signal of working face.

The process of mechanical zinc plating was simulated by discrete element method using the EDEM software. The motion characteristics of zinc powder when being stricken by the impact medium at different velocities were studied. The results showed that the zinc powder was compressed longitudinally at the initial stage of mechanical zinc plating, and a zinc coating was finally formed by rearranging and compression deformation longitudinally and transversely. The zinc powder at top layer deformed and rearranged primarily, while the zinc powder at middle and bottom layers rearranged mainly. The zinc coating formed by mechanical plating at an impact velocity of 1.0 m/s was smooth and flat with an 0-grade adhesion. The simulation results were essentially consistent with the experimental results. [ABSTRACT FROM AUTHOR]

Objective: To explore the effects of Guizhi Tang on the inflammatory cytokines in myocardial ischemia and hyperlipidemia rats., Method: The early changes of hyperlipid and atherosclerosis are caused by utilizing multiple factors including feeding hyperlipid and propylthiouracil and high doses of vitamin D3 for 12 weeks. Sixty male SD rats were randomly divided in to 5 groups: control group, model group, simvastatin group, low-dosage Guizhi Tang group, high-dosage Guizhi Tang group. At the end of six weeks treatment, pituitrin(pit) is abdominal cavity injected every 24 hours for a total of three times. Detecting the serum levels of SES, CRP, NO, SOD, MDA and the content of cardiac muscle tissue SOD, MDA, The expression of TNF-alpha in cardiac muscle tissue was detected by immunohistochemistry., Result: Guizhi Tang significantly decreased levels of SES, CRP and MAD, increased levels of NO and SOD, Guizhi Tang markedly decreased the level of protein expression of TNF-alpha in cardiac muscle tissue., Conclusion: Guizhi Tang may inhibit the proinflammatory factors and oxidation in myocardial ischemia and hyperlipidemia rats.