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171.
In order to understand the water quality and the genotoxicity of various surfaces in the Guangzhou section of the Pearl River during January to December of 2008, we investigated and studied the current water situation of the surface microlayer (SML) and the subsurface water (SSW) in Guanzhou section (Zhongda Dock and Yuzhu Dock) of the Pearl River by chemical analysis and biological monitoring method (Vicia faba micronucleus test). The results showed that during these months concentrations of the indexes of the two docks water such as total nitrogen (TN), total phosphorus (TP), chemical oxygen demand (COD) exceeded the national III level of surface water quality, and the indexes of SML were much higher than the ones of SSW (P?< 0.05), and the exceeding rate of TN, TP of SML was 100%. According to the eutrophic evaluation standard, the water bodies of SML and SSW in the two docks were in a eutrophication during these months. The eutrophication and pollution of SML was more serious, and the highest index of eutrophication (E value) was up to 81.9, which also had obvious difference with COD and TP (P?< 0.05). The water of SML in the two docks enriched to N, P, and chlorophyll a (Chl. a) seriously, and the enrichment factor of SML in Zhongda Dock to N, P, and Chl. a was 0.71 ?? 2.78, 0.98 ?? 1.18, and 0.49 ?? 13.99, respectively, and the one in the Yuzhu Dock was 1.09 ?? 1.52, 1 ?? 1.14, and 0.72 ?? 4.07, respectively. Through inspecting the water genotoxicity of various layers by V. faba micronucleus test, we could know that the average annual MCN?? of SML and SSW in the two docks was 6.09??, 5.53??, 5.57??, and 5.249??, respectively. In general, the above value of SML was a little higher than the one of SSW, but there was not a remarkable difference (P?> 0.05). This research shows that the water quality in a medium to heavy eutrophication in the Guangzhou section of Pearl River belongs to national III ?? IV level, and SML has the capability of enrichment to the pollutants such as N and P and induces the increase of micronucleus rate of V. faba tip cell. The study also indicates that there may be genotoxicity matters such as N, P in water body.  相似文献   
172.
Recently, ling et al. (2013) published the paper entitled as above. In Section 2.3, Adsorption kinetics of MBT, authors noticed that "The pseudo first-order kinetic model (Eq. (1)) and the pseudo second-order kinetic model (Eq. (2))" were used (Do,an et al., 2007; Eftekhari et al., 2010):  相似文献   
173.
The inactivation effects of pressurized CO2 against bacteriophage Qβ and ΦX174 were investigated under the pressure of 0.3–0.9 MPa, initial concentration of 107–109PFU/mL, and temperature of17.8°C–27.2°C. The optimum conditions were found to be 0.7 MPa and an exposure time of 25 min. Under identical treatment conditions, a greater than 3.3-log reduction in bacteriophage Qβ was achieved by CO2, while a nearly 3.0 log reduction was observed for phage ΦX174. The viricidal effects of N2O(an inactivation gas with similar characteristics to CO2), normal acid(HCl), and CO2 treatment with phosphate buffered saline affirmed the chemical nature of CO2 treatment. The pumping cycle, depressurization rate, and release of intracellular substances caused by CO2 were its viricidal mechanisms. The results indicate that CO2 has the potential for use as a disinfectant without forming disinfection by-products.  相似文献   
174.
● Methanol effectively reduces CO, HC, CO2, PM, and PN emissions of gasoline vehicles. ● Elemental composition of methanol directly affects the reduction of emissions. ● Several physicochemical properties of methanol help reduce vehicle emissions. The transport sector is a significant energy consumer and a major contributor to urban air pollution. At present, the substitution of cleaner fuel is one feasible way to deal with the growing energy demand and environmental pollution. Methanol has been recognized as a good alternative to gasoline due to its good combustion performance. In the past decades, many studies have investigated exhaust emissions using methanol-gasoline blends. However, the conclusions derived from different studies vary significantly, and the explanations for the effects of methanol blending on exhaust emissions are also inconsistent. This review summarizes the characteristics of CO, HC, NOx, CO2, and particulate emissions from methanol-gasoline blended fuels and pure methanol fuel. CO, HC, CO2, particle mass (PM), and particle number (PN) emissions decrease when methanol-blended fuel is used in place of gasoline fuel. NOx emission either decreases or increases depending on the test conditions, i.e., methanol content. Furthermore, this review synthesizes the mechanisms by which methanol-blended fuel influences pollutant emissions. This review provides insight into the pollutant emissions from methanol-blended fuel, which will aid policymakers in making energy strategy decisions that take urban air pollution, climate change, and energy security into account.  相似文献   
175.
Environmental Science and Pollution Research - The effects of air pollution on sleep and dementia remain unclear. The objective of this study was to investigate the effects of air pollution on...  相似文献   
176.
Environmental Science and Pollution Research - To enhance dye removal and energy recovery efficiencies in single-pair electrode photocatalytic fuel cell (PFC-AC), dual cathodes PFC (PFC-ACC) and...  相似文献   
177.
178.
By interpreting disasters as opportunities to initiate the fulfilment of development needs, realise the vulnerability of the affected community and environment, and extend the legacy of relief funds and effort, this paper builds upon the concept linking relief, rehabilitation and development (LRRD) in the sanitation sector. It aims to use a composite of case studies to devise a framework for a semi‐hypothetical scenario to identify critical components and generic processes for a LRRD action plan. The scenario is based on a latrine wetland sanitation system in a Muslim community. Several sub‐frameworks are developed: (i) latrine design; (ii) assessment of human waste treatment; (iii) connective sanitation promotion strategy; and (iv) ecological systems and environmental services for sanitation and development. This scenario illustrates the complex issues involved in LRRD in sanitation work and provides technical notes and references for a legacy plan for disaster relief and development.  相似文献   
179.
180.
Rice samples (n = 482) harvested for 2010–2012 in South Korea were analyzed for zearalenone content by high-performance liquid chromatography and fluorescence detection. The exposure of the Korean populations was assessed by a deterministic approach. Because the proportion of non-detectable results was >80% in white rice but less than <60% in brown rice, the zearalenone levels for white rice were reported as 0.52 µg kg?1 as lower bound and 2.54 µg kg?1 as upper bound, while for brown rice the middle bound value was 13.9 µg kg?1. The average dietary intake of zearalenone from white and brown rice by the Korean population was estimated to be 1.5 ng kg?1 body weight (bw) day?1 each. For heavy consumers, the average intakes were 18.5 and 10.1 ng kg?1 bw day?1, respectively. The age groups with the highest zearalenone intake were 1–2-year-old children for white rice and 3–6-year-old children for brown rice. Overall, the dietary exposure of the Korean population to zearalenone from white and brown rice was found to be lower than the provisional maximum tolerable daily intake of 0.5 μg kg?1 bw day?1.  相似文献   
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