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Based on the tests of rock mechanics and the measurement results of relaxation zone of roadway, the characteristics of deformation and failure of the surrounding rock masses were revealed under conditions of very weak cementation formation of complex geology. With FLAC3D, the variation law of deformation and plastic zone of surrounding rock was studied after excavation in 5 kinds of roadway, the effective laws of the depths and lateral pressure coefficient on the stability of the surrounding rock were researched. To master the deformation of surrounding rock and mechanical properties of the support structure timely, optimize the design of roadway supporting and guide the construction, the convergence deformation of the surrounding rock, mechanical properties of the I-beam and the concrete lining were monitored at real-time. The monitoring results show that, by using the combined support of I-beam, mesh reinforcement and concrete lining in a development roadway of poorly consolidated formations can effectively control the deformation of the surrounding rock and ensure stability and safety of the roadway in long time. [ABSTRACT FROM AUTHOR]

Objective: To analyze and further improvement the application of the China Infectious Diseases Automated-alert and Response System (CIDARS) in Guangxi Zhuang Autonomous Region., Methods: Results related to the amount of signal, proportion of signal responded, time to signal response, manner of signal verification and on each signal of Guangxi in CIDARS from 2009 to 2011 were described. Performance was compared between the periods of pre/ post the adjustment of parameters in CIDARS on December 10, 2010., Results: A total of 29 788 signals were generated on 16 infectious diseases in the system in Guangxi. 100% signals had been responded with the median time to response as 1.5 hours. The average amount of signal per county per week was 1.7;with 624 signals(2.09%)verified as suspected outbreaks preliminarily and 191 outbreaks of 9 diseases were finally confirmed by further field investigation. The sensitivity of CIDARS was 89.25% , and the timeliness of detection was 2.8 d. After adjusting the parameter of CIDARS, the number of signals reduced, and the sensitivity and timeliness of detection improved for most of the diseases., Conclusion: The signals of CIDARS were responded timely, and the performance of CIDARS might be improved by adjusting the parameters of early-warning model, which helped enhance the ability of outbreaks-detection for local public health departments. However the current proportion of false positive signals still seemed to be high, suggesting that both the methods and parameters should be improved, according to the characteristics of different diseases.

To investigate pollution characteristics of dioxin-like polychlorinated biphenyls (DL-PCBs) in Gudao Region, Dongying City, twenty surface soil samples were collected in April, 2011. The DL-PCBs in soil samples were determined by Soxhelt extraction-Florisil purification-Gas Chromatography(GC)-Electron Capture Detector (ECD). The concentration of DL-PCBs in surface soils ranged from 1.4 microg x kg(-1) to 7.4 microg x kg(-1), with the mean concentration of (3.5 +/- 1.7) microg x kg(-1). The total TEQ level was between 1.2 ng x kg(-1) and 31.8 ng x kg(-1), and the mean TEQ was 5.4 ng x kg(-1), which exceeded the Canadian soil environment quality guidelines (4.0 ng x kg(-1)). The congener profiles of DL-PCBs were similar among sites. Tetra-CB and penta-CB were the major homologues in all soil samples, together accounting for more than 80% of the total DL-PCBs. The level of DL-PCBs exhibited a decreasing trend with the increasing distance from the Gudao town to the suburb, which could be attributed to the chemical plants around the town. The correlation analysis showed that the concentration of DL-PCBs was positively correlated with the organic matter content and clay particle content (R2 were 0.732 and 0.687, separately, P < 0.01), but negatively correlated with the sand particle content (R2 = -0.438, P < 0.05).