错流式膜-生物反应器处理生活污水及其生物学研究

用错流式膜－生物反应器（ＣｒｏｓｆｌｏｗＭｅｍｂｒａｎｅＢｉｏＲｅａｃｔｏｒ简称ＣＭＢＲ）进行处理生活污水试验并研究其生物动力学参数．结果表明：当ＨＲＴ为５ｈ,ＳＲＴ为１５ｄ,膜面流速为４ｍ／ｓ,膜通量为７５、１５０Ｌ／（ｍ２·ｈ）时,ＣＭＢＲ处理生活污水试验的去除率为：ＣＯＤ＞９７％、ＮＨ３－Ｎ＞９７％、浊度≥９８％;对ＳＳ和总Ｅ．ｃｏｌｉ则达到１００％,出水水质优于建设部生活杂用水回用标准ＣＪ２５．１－８９．生物相分析表明,污泥中没有原、后生动物,只有菌胶团．推导了ＣＭＢＲ稳态运行时的生物浓度计算公式,进而求得表观产率因数Ｙｇ为０．６５,衰减常数Ｋｄ为０．１ｄ－１．     

无机膜-生物反应器处理生活污水试验研究

用无机膜－生物反应器进行处理生活污水试验,结果表明,当ＨＲＴ为５ｈ,膜通量为７５－１５０Ｌ／（ｍ＾２．ｈ）膜面流速为４ｍ／ｓ,ＳＲＴ为５,１５,３０ｄ时,分别经过１０,１６,１４ｄ,运行,生物反应器ＭＬＳＳ达到稳定值３．１,１０．７,１７．３ｇ／Ｌ,对ＣＯＤ,ＮＨ３－Ｎ和浊度的去除率分别为超过９６％,９５％,９８％,对ＳＳ和Ｅ．ｃｏｌｉ的去除率则达１００％;试验出水水质优于建设部生活杂用水水质标准     

Present and potential future contributions of sulfate,black and organic carbon aerosols from China to global air quality,premature mortality and radiative forcing

Aerosols are harmful to human health and have both direct and indirect effects on climate. China is a major contributor to global emissions of sulfur dioxide (SO₂), a sulfate (SO₄^2?) precursor, organic carbon (OC), and black carbon (BC) aerosols. Although increasingly examined, the effect of present and potential future levels of these emissions on global premature mortality and climate change has not been well quantified. Through both direct radiative effects and indirect effects on clouds, SO₄^2? and OC exert negative radiative forcing (cooling) while BC exerts positive forcing (warming). We analyze the effect of China's emissions of SO₂, SO₄^2?, OC and BC in 2000 and for three emission scenarios in 2030 on global surface aerosol concentrations, premature mortality, and radiative forcing (RF). Using global models of chemical transport (MOZART-2) and radiative transfer (GFDL RTM), and combining simulation results with gridded population data, mortality rates, and concentration–response relationships from the epidemiological literature, we estimate the contribution of Chinese aerosols to global annual premature mortality and to RF in 2000 and 2030. In 2000, we estimate these aerosols cause approximately 470 000 premature deaths in China and an additional 30 000 deaths globally. In 2030, aggressive emission controls lead to a 50% reduction in premature deaths from the 2000 level to 240 000 in China and 10 000 elsewhere, while under a high emissions scenario premature deaths increase 50% from the 2000 level to 720 000 in China and to 40 000 elsewhere. Because the negative RF from SO₄^2? and OC is larger than the positive forcing from BC, Chinese aerosols lead to global net direct RF of ?74 mW m^?2 in 2000 and between ?15 and ?97 mW m^?2 in 2030 depending on the emissions scenario. Our analysis indicates that increased effort to reduce greenhouse gases is essential to address climate change as China's anticipated reduction of aerosols will result in the loss of net negative radiative forcing.     

Bioethanol production from enzymatically saccharified lawn clippings from a golf course

The utilization of bioethanol is being focused on as a fuel alternative to oil and or natural gas. Bioethanol production from cellulosic plant residues is one of the solutions proposed for the problems caused by usage of food crops that are also vital for human consumption, such as sugar cane and corn, as a source of bioethanol. However, to utilize these new sources for bioethanol production, conditions for saccharification in each different material have not been optimized. In this study, we reported some optimum conditions for the saccharification of Korean lawn grass (KL) and bent grass (BG) using acremonium cellulase and endoglucanase as saccharifying enzymes for ethanol fermentation. With respect to saccharification of KL and BG, 0.19 and 0.18 g of d-glucose per g-substrate at maximum were produced, respectively. Comminution with a ball mill was found to be effective in the saccharification of KL, while ball-milled BG showed no significant improvement in saccharification. Being incorporated with 99 % of d-glucose consumption, saccharified KL was incubated for 3 days with Saccharomyces cerevisiae and Zymomonas mobilis, respectively, and each mixture fermented to ethanol yielding approximately 100 % of theoretical values from d-glucose consumption, respectively.     

Elevated nitrogen isotope ratios of tropical Indian aerosols from Chennai: Implication for the origins of aerosol nitrogen in South and Southeast Asia

To better understand the origins of aerosol nitrogen, we measured concentrations of total nitrogen (TN) and its isotope ratios (δ¹⁵N) in tropical Indian aerosols (PM₁₀) collected from Chennai (13.04°N; 80.17°E) on day- and night-time basis in winter and summer 2007. We found high δ¹⁵N values (+15.7 to +31.2‰) of aerosol N (0.3–3.8 μg m^?3), in which NH₄⁺ is the major species (78%) with lesser contribution from NO₃^? (6%). Based on the comparison of δ¹⁵N in Chennai aerosols with those reported for atmospheric aerosols from mid-latitudes and for the particles emitted from point sources (including a laboratory study), as well as the δ¹⁵N ratios of cow-dung samples (this study), we found that the atmospheric aerosol N in Chennai has two major sources; animal excreta and bio-fuel/biomass burning from South and Southeast Asia. We demonstrate that a gas-to-particle conversion of NH₃ to NH₄HSO₄ and (NH₄)₂SO₄ and the subsequent exchange reaction between NH₃ and NH₄⁺ are responsible for the isotopic enrichment of ¹⁵N in aerosol nitrogen.     

Levels and regional trends of persistent organochlorines and polybrominated diphenyl ethers in Asian breast milk demonstrate POPs signatures unique to individual countries

Human breast milk samples collected in 2007–2008 from four countries, Vietnam (Hanoi), China (Beijing), Korea (Seoul) and Japan (Sendai, Kyoto and Takayama), were analyzed for persistent organic pollutants (POPs) such as dichlorodiphenyltrichloroethane and its metabolites (DDTs), chlordane-related compounds (CHLs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). Comparing with previous surveys, the present study indicates that the DDTs in breast milk from China and Vietnam had gradually decreased during the last decade, but were still 5–10 times higher than those in other nations. The ratios of p,p′-DDE/p,p′-DDT and o,p′-DDT/p,p′-DDT were higher in Beijing than in the other countries, suggesting that there is less fresh intake of commercial DDT products and a possible exposure to dicofol in China. CHL and PCB levels were relatively higher in mothers from Japan, whereas β-HCH and HCB were more common in Chinese women. In Japan, it is suspected that mothers in the urban/coastal area (Sendai) were more continuously exposed to organochlorine pesticides (OCPs) than mothers in the rural/inland area (Takayama). In addition, OCP levels in primiparae were significantly higher than those in multiparae from Japan and Korea. These indicate that both parity and regional factors are major determinants of the levels of OCPs and PCBs in human milk. On the other hand, higher concentrations of PBDEs were observed in mothers' milk from Korea. The congener was dominated by BDE-47 (43–54%), followed by BDE-153 (23–33%) in all regions except for Beijing where BDE-28 (23%) was relatively abundant. In Japanese breast milk, regional and parity-dependent distributions were not observed for PBDEs. Among PBDE congeners, age-dependency was observed for BDE-153, which was negatively correlated (p < 0.05) to the age of mothers in Kyoto (17 participants were housewives), while it increased with age in Sendai (10 participants were clerks). No such correlation was seen for BDE-47, indicating that BDE-47 was ingested and assimilated via different kinetics or routes from BDE-153 in Japan.     

Sources of organochlorine pesticides in air in an urban Mediterranean environment: volatilisation from soil

Organochlorine pesticide (OCP) cycling was studied in the area of Banja Luka, Bosnia and Herzegovina, over 3 days in summer with high temporal (4 h-means) and spatial (3 sites distanced 3-6 km) resolutions. Elevated levels of DDX compounds (i.e. o,p'- and p,p'-isomers of DDT, DDE and DDD, 44-74 pg m(-3) at the urban sites and 27 pg m(-3) as a background level), HCH (α-, β- and γ-isomers, 52-70 vs. 147 pg m(-3)), HCB (34-48 vs. <0.1 pg m(-3)) and pentachlorobenzene (6.8-9.9 vs. 6.0 pg m(-3)) were found. The variation of OCP levels at the two urban sites was not in phase, except for most DDX compounds. This was related to background levels, which for HCH were higher than in the urban area. Vertical profiles between samples collected from 1.1 and 2.3 m (part of the time 0.6 and 2.3 m) above a soil, which was only moderately contaminated by OCPs (0.12 ng g(-1) HCH, 0.11 ng g(-1) DDX, 0.44 ng g(-1) HCB) were analysed. Volatilisation from the ground caused negative vertical concentration gradients of HCH isomers (day and night), but not for HCB (except for 1 day-time sample) and DDX compounds (except p,p'-DDD, day-time, sporadically). The concentration in air and the vertical concentration gradient of the HCH isomers varied with air temperature (day-time maxima), while the variation of the HCB concentration was inversely related to air temperature and was determined by mixing (night-time maxima). α- and β-HCH were volatilised from soil throughout the three days, even during periods of cooling. Fugacity calculations, based on the absorption in soil organic matter as the process determining retention in soil, underestimated the volatilisation of β-HCH and p,p'-DDD. It is concluded that the representativeness of point measurements of OCPs in urban areas is limited by the spatial variability of soil contamination.     

超滤膜-生物反应器处理生活污水及其水力学研究

用超滤膜－生物反应器进行处理生活污水试验并研究其水力学行为。结果表明,当ＨＲＴ为５ｈ、ＳＲＴ为３０ｄ、膜面流速为４ｍ／ｓ膜流量为７５Ｌ／（ｍ＾２·ｈ）时,试验出水水质优于建设部生活杂用水水质标准ＣＪ２５．１－８９,可直接回用。