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The vertical and horizontal distribution of CO concentration in the tunnel fire under longitudinal ventilation was studied by scale modeling technique. A 1/4 rectangular tunnel model of 0.4m width, 0.8m height, and 3.48m length was constructed. A series of experiments were conducted with five different ventilation velocities and with n-Heptanes pool fires in side-length pan of 15cm. It was found that there exists a critical velocity at which the mass loss rate is the highest, and when the smoke is laminar flow, the stratification of CO concentration is more distinct than near the fire source. When the smoke is turbulent flow, the stratification of CO is indistinct. The maximum CO concentration decreased along the tunnel model, and the delaying time of the maximum CO concentration decreased with the increase of ventilation velocity. [ABSTRACT FROM AUTHOR]

Five dominant strains, capable of treating leachate effectively, were isolated. The results showed that the removal efficiency of COD by using the mixed strains was higher than the pure strain, reaching 46.8%. The optimal inoculum concentration and the treatment time were 10.0% and 120 h respectively. The removal rate of COD reached the maximum at the temperature of 35°C and pH of 7.0. The results also indicated that adding carbon sources was beneficial to decomposing the organic pollutants in leachate. Moreover the dominant strains had also an effect on decomposing nonbiodegradable organic pollutants, that E260 was 29.4%. [ABSTRACT FROM AUTHOR]

Based on the analysis of comparability, a bench-scale (1:4) facility with the configuration of "fire room-long passage-remote room" is designed to study the spatial distribution and risk of CO in building fire. A series of experiments are carried out on the facility. It is found that CO concentration increases with the height of probes in the non-firesource-field. In the long passage, CO concentration decreases with the distance from the firesource. Additionally, CO concentration varies greatly at the upper part, but is uniform at the lower part in the long passage. However, CO distribution in the remote room is just the opposite. In addition, CO concentration in the remote room is greatly influenced by various openings. These characteristics of CO distribution in the non-firesource-field indicate that the long passage and the remote room should be treated differently in research. Meanwhile, the present article puts forward the concept of index of toxicity to analyze the smoke toxicity in the non-firesource-field, which has the superiority to be used to assess the risk grade of non-firesource-field. [ABSTRACT FROM AUTHOR]

This paper investigates the axial temperature profiles in buoyant plume of rectangular source fuel jet fires. Experiments are carried out in this work by rectangular source nozzles with aspect ratio (width/length, W/L) ranged from 1:1 (axi-symmetrical) to 1:71 (linear) in Hefei city (100.8 kPa) and Lhasa (64.3 kPa). The axial temperature profile is theoretically deduced for different source dimensions and heat release rates, based on the conservation of Froude number (momentum/buoyancy) where its dependency on source initial momentum are then correlated from the experimental data. The previous classic correlation for plume temperature profile established by Quintiere is extended to jet fires by including the effect of source momentum as well as the dimensions of the rectangular burner. The proposed correlation is also further extended to the special sub-atmospheric pressure condition (Lhasa, 64.3 kPa). [ABSTRACT FROM AUTHOR]