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Min GOU Jing ZENG Huizhong WANG Yueqin TANG Toru SHIGEMATSU Shigeru MORIMURA Kenji KIDA 《Frontiers of Environmental Science & Engineering》2016,10(2):368-380
The microbial community structures of two mesophilic anaerobic chemostats, one fed with glucose, the other with starch as sole carbon sources, were studied at various dilution rates (0.05–0.25 d–1 for glucose and 0.025–0.1 d–1 for starch) during two years continuous operation. In the glucose-fed chemostat, the aceticlastic methanogen Methanosaeta spp. and hydrogenotrophic methanogen Methanoculleus spp. predominated at low dilution rates, whereas Methanosaeta spp. and the hydrogenotrophic Methanobacterium spp. predominated together when dilution rates were greater than 0.1 d–1. Bacteria affiliated with the phyla Bacteroidetes, Spirochaetes, and Actinobacteria predominated at dilution rates of 0.05, 0.1, and 0.15 d–1, respectively, while Firmicutes predominated at higher dilution rates (0.2 and 0.25 d–1). In the starch-fed chemostat, the aceticlastic and hydrogenotrophic methanogens coexisted at all dilution rates. Although bacteria belonging to only two phyla were mainly responsible for starch degradation (Spirochaetes at the dilution rate of 0.08 d–1 and Firmicutes at other dilution rates), different bacterial genera were identified at different dilution rates. With the exception of Archaea in the glucose-fed chemostat, the band patterns revealed by denaturing gradient gel electrophoresis (DGGE) of the microbial communities in the two chemostats displayed marked changes during long-term operation at a constant dilution rate. The bacterial community changed with changes in the dilution rate, and was erratic during longterm operation in both glucose-fed and starch-fed chemostats. 相似文献
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Collection characteristics of a double stage scrubber to eliminate the paint mist from a spray booth
A 4.5 m3/min laboratory paint spray booth was built adopting a double-stage scrubber with heavy oil as the scrubbing liquid. The relationship between the collection efficiency E and the pressure drop ΔP was studied using a cylindrical paper tilter and a Digital Dust Counter. Experimental results indicated that the collection efficiency in this system is in accordance with the collection efficiency equation based on the theory of inertial impaction. With water used as the scrubbing liquid, the factor K is about 0.5 for single-stage scrubbing, while it is 0.6 for double-stage scrubbing. At a pressure drop of 60 mm of H2O, heavy oil used as the scrubbing liquid gained about 2.0% more in collection efficiency than water. The zigzag baffler equipped for removing heavy oil mist was also effective for the paint mist collector, and 99.1% of E was gained at a pressure drop of 135 mm H2O. 相似文献
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So Kazama Toshiki Aizawa Toru Watanabe Priyantha Ranjan Luminda Gunawardhana Ayako Amano 《Sustainability Science》2012,7(1):45-54
Flooding and inundation are annual events that occur during the rainy season in Cambodia, and inundation has a strong relationship
with human health. This study simulated the coliform bacteria distribution using a hydraulic model and estimated the impact
of inundation on public health using a dose–response model. The model parameters were calibrated using field survey data from
Cambodia and obtained good agreement with the coliform group count distribution. The results suggest that the impact of inundation
on human health is most noticeable in residential areas. The annual average risk of infection during medium-sized flood events
is 0.21. The risk due to groundwater use ranges from 0.12 to 0.17 in inundation areas and reaches as high as 0.23 outside
the inundation areas. The risk attributed to groundwater use is therefore higher than that for surface water use (0.02–0.06),
except in densely populated areas at the city center. There is a high risk for infection with waterborne disease in residential
areas, and the annual average risk during small flood events is 0.94. An assessment of possible countermeasures to reduce
the risk shows that the control of inundation may bring more risk to public health in Cambodia. Shallower inundation water
(<0.3 m) leads to a higher risk of infection, but if the depth is greater than 2 m, the risk is low in residential areas.
The simulated results explain the spatial distributions of infection risk,, which are vitally important for determining the
highest priority places with relatively high risk and will be helpful for decision makers when considering the implementation
of countermeasures. 相似文献
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Koike Kentaro Yamaji Toru Nishida Takahiro Yonamine Kazuhide Adachi Akihiro Nakagawa Kozo 《Journal of Material Cycles and Waste Management》2022,24(4):1368-1377
Journal of Material Cycles and Waste Management - Copper slag fine aggregate (CUS) is 30% denser than normal aggregate is an effective material for port and harbor structures demanding high-density... 相似文献
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Kamal Baharin Nur Syahirah Cherdkeattikul Supitchaya Kanada Nami Hara Hirofumi Mizuno Satoru Sawai Toru Fuchihata Manabu Ida Tamio 《Journal of Material Cycles and Waste Management》2023,25(1):17-36
Journal of Material Cycles and Waste Management - Growing concern over fossil fuel depletion and the environmental impact of greenhouse gases have driven the demand for solid biofuel energy as an... 相似文献
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Susan Collet Hiroaki Minoura Toru Kidokoro Yukihiro Sonoda Yukio Kinugasa Prakash Karamchandani 《Journal of the Air & Waste Management Association (1995)》2014,64(2):175-183
To improve U.S. air quality, there are many regulations on-the-way (OTW) and on-the-books (OTB), including mobile source California Low Emission Vehicle third generation (LEV III) and federal Tier 3 standards. This study explores the effects of those regulations by using the U.S. Environmental Protection Agency's (EPA) Community Multiscale Air Quality (CMAQ) model for 8-hr ozone concentrations in the western and eastern United States in the years 2018 and 2030 during a month with typical high ozone concentrations, July. Alterations in pollutant emissions can be due to technological improvements, regulatory amendments, and changes in growth. In order to project emission rates for future years, the impacts of all of these factors were estimated. This study emphasizes the potential light-duty vehicle emission changes by year to predict ozone levels. The results of this study show that most areas have decreases in 8-hr ozone concentrations in the year 2030, although there are some areas with increased concentrations. Additionally, there are areas with 8-hr ozone concentrations greater than the current U.S. National Ambient Air Quality Standard level, which is 75 ppb.
Implications:
To improve U.S. air quality, many regulations are on the way and on the books, including mobile source California LEV III and federal Tier 3 standards. This study explores the effects of those regulations for 8-hr ozone concentrations in the western and eastern United States in the years 2018 and 2030. The results of this study show that most areas have decreases in 8-hr ozone concentrations in 2030, although there are some areas with increased concentrations. Additionally, there are areas with 8-hr ozone concentrations greater than the current U.S. National Ambient Air Quality Standard level. 相似文献
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Determination of PCBs, PCDDs and PCDFs in insulating oil samples from stored Chinese electrical capacitors by HRGC/HRMS 总被引:2,自引:0,他引:2
Homologue and congener profiles of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in commercial PCBs formulations are key information for the source identification of PCBs contamination as well as for the risk assessment caused by potential exposure. The isotope dilution technology in combination with high resolution gas chromatography-high resolution mass spectrometry (HRGC/HRMS) has made the accurate determination of such profiles possible. So far, various commercial PCB formulations except Chinese products have been successfully determined. Two PCBs containing insulating oil samples from stored Chinese electrical capacitors have been determined with the same methodology for comparability. The total concentration PCBs in two oil samples were 790 000 μg g−1 and 720 000 μg g−1, respectively. TriCBs, TetraCBs, and DiCBs were found to be most abundant. Concentration of dioxins contamination in two samples is 650-670 ngTEQ g−1, of which 69-71 ngTEQ g−1 from PCDD/Fs with the predominant congeners of 1,2,7,8-TeCDF; 2,3,7,8-TeCDF; 2,3,4,7,8-PeCDF and 1,2,3,7,8-PeCDF. The contributions of DL-PCBs in total TEQ in both samples were more than 85%. The dioxin-like toxicity in insulating oils contained in electrical capacitors could be considered receive attention as an important dioxins source if such wastes are not managed in an environmentally sound manner. 相似文献
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