Experimental Study on the Fire Performance of Tubular Steel Columns with Membrane Protections for Prefabricated and Modular Steel Construction.

Experimental research was conducted to study the fire resistance of steel tubular columns used in prefabricated and modular construction. In order to achieve high-efficient prefabrication and fast on-site installation, membrane protections using board products and thermal insulation blankets are adopted as the favorable protection method. Three protected tubular columns were tested in a full-scale column furnace with axial load applied. The study variables were different membranes, including fiber reinforced calcium silicate (FRCS) boards, rock wool and aluminum silica (Fiberfrax) insulations. The results suggest that one layer of 12 mm FRCS board with rock wool insulation has insufficient fire protection. However, steel columns protected with two layers of 12 mm FRCS boards with insulation appeared to have good fire resistances and could achieve a fire resistance rating as high as 2.5~3.0 h.

Study of Nitrogen Removal Performance When Treating Low Carbon Sewage Using External Solid Carbon Sources in SBBR Systems.

Based on low carbon wastewater as the research object and using corncob as an external solid carbon source, the performance of corncob organic matter was assessed for its release potential, quantity of release, and safety of use. The effects of varying quantities of the solid carbon source on simultaneous nitrification and denitrification were investigated in a sequencing biofilm batch reactor (SBBR). Results show that the regularity of corncob as solid carbon source material was linear, with released concentrations of heavy metals being below the Chinese national standard limit values for heavy metals according to the surface water environment quality standards (I and II) (GB3838-2002). When temperatures were within 28~31°C, the dissolved oxygen level was 4.0 ± 0.2 mg/L and the pH conditions were within 7.5~8.0. The optimal quantity for corncob dosing was 5 g per 1.5 L of low carbon wastewater. Following treatment, the average effluent concentrations of NH4+-N and TN were 2.85 mg/L and 4.51 mg/L, respectively. The effluent concentration of NH4+-N, TN had reached the A level national standard of sewage treatment plant pollutant discharge standard (GB18918-2002).

Atmospheric arsenic (As) study at five characteristic sampling sites in Taiwan.

The main purpose for this study is to observe the seasonal and monthly variations for arsenic (As) in total suspended particulates (TSP) concentration and dry deposition at five characteristic sampling sites during the years 2009 and 2010 in central Taiwan. The results show that the highest and lowest monthly average As concentrations in TSP occurred in January and May at Bei-shi (suburban/coastal) and Quan-xing (industrial) sampling sites. In addition, the results show that the highest and lowest monthly average As dry deposition occurred in October and May at Chang-hua (downtown) and Gao-mei (wetland) sampling sites. This study reflected that the mean highest As concentrations in TSP and mean highest As dry deposition occurred at Quan-xing (industrial). However, the mean lowest As concentrations in TSP and mean lowest As dry deposition also occurred at Gao-mei (wetland). Regarding seasonal variation, the results show that the As average seasonal concentration order in TSP was winter > spring > fall > summer, respectively, at Chang-hua (downtown) and He-mei (residential) sampling sites. Finally, the order of As average seasonal dry deposition was fall > winter > spring > summer, respectively, at Chang-hua (downtown), He-mei (residential), and Gao-mei (wetland) sampling sites.

Dry deposition of Mn, Zn, Cr, Cu and Pb in particles of sizes of 3 µm, 5.6 µm and 10 µm in central Taiwan.

This investigates the concentrations of Mn, Zn, Cr, Cu, and Pb ambient air in total suspended particulates (TSPs) and dry deposition. The ratios of the calculated to measured dry deposition fluxes of ambient-air Mn, Zn, Cr, Cu and Pb at five characteristic sampling sites from 2009 to 2010 were determined using two dry deposition models. Experimental results demonstrate that the mean concentrations of metallic elements in TSPs and dry deposition were highest at the Quan-xing (industrial) sampling site, which is surrounded by various industrial factories and is in a severely polluted area. The mean seasonal concentrations of metallic elements in TSPs were highest in the winter and fall at all five sites. The analytical concentrations of metallic elements in fall and winter at these five sites were elevated in low winds. The Baklanov model yielded more accurate predictions concerning the dry deposition of metallic elements in ambient air when the sizes of the deposited particles were <5.6 µm, and the Noll and Fang model yielded better predictions when the sizes of the particles were >5.6 µm.

Measurement and modeling of concentrations of ambient air particles, chromium, copper and lead pollutants concentrations, as well as dry deposition in central Taiwan.

The main purpose of this investigation was to monitor ambient air particles and metallic elements (Cr, Cu and Pb) in total suspended particulates (TSP) concentration, dry deposition. Furthermore, the calculated/measured dry deposition flux ratios of ambient air particles and metallic elements (Cr, Cu and Pb) were evaluated using three dry deposition models at five characteristic sampling sites for the 2009-2010. The results show that the average concentrations of metallic elements Cr, Cu and Pb in TSP were highest at Bei-shi (suburban/coastal) and the lowest at Gao-mei (wetland) among the five characteristic sampling sites during the years 2009-2010. This study also shows that the mean rates of dry deposition of metallic elements Cr and Cu were highest at Quan-xing (industrial) and lowest at Bei-shi (suburban/coastal) and Chang-hua (downtown). Finally, the Noll and Fang model was found to yield better predictions of the dry deposition of ambient air particles and metallic elements Cr and Cu than any of the other deposition models.

Study of atmospheric metallic elements pollution in Asia during 2000-2007.

The main purpose of this study is to observe the concentration variations for metallic elements in the atmosphere in Asian countries during 2000-2007. These metallic elements typically generated by human activities are directly or indirectly detrimental to human health. The results show that the highest average metallic elements concentrations of Fe, Cu, Zn and Mn in total suspended particles (TSP) were in China, while the lowest average concentrations were in Japan. For metallic elements Cr and Ni, the highest average concentrations in Japan. The highest average concentrations for metallic element Pb were in China while the lowest average concentrations were in Hong-Kong. These analytical results show that the highest average metallic elements concentrations of Pb, Mn, Cr and Ni in PM(10) occurred in Hong-Kong while the lowest average concentrations were in India. In addition, the lowest average concentrations for Zn and Fe occurred in India. These analytical results demonstrate that the highest average concentrations of Pb in PM(2.5) occurred in Hong-Kong while the lowest average concentration was in Japan. The lowest average concentrations for Cu, Mn, Cr and Ni, the average lowest concentrations occurred in Bangladesh. Taiwan had the lowest average concentrations of Cu and Ni among all Asian countries studied during 2000-2007.