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901.
厌氧消化处理制药废水微生物类群的研究 总被引:2,自引:0,他引:2
本文厌氧消化处理制药废水,在不同消化温度条件下,进行了厌氧微生物类群和种群数量的测定.消化温度39℃,各种群菌量最多.消化温度24℃,各种群菌量最少.消化温度33℃和35℃,各种群菌量与消化温39℃度相比,菌量有所减少,但菌量差别不太明显.例如:甲烷细菌消化温度24℃比39℃菌量减少3×10~4倍,消化温度33℃和35℃与39℃比较,甲烷细菌分别减少4.1×10~2倍和3.2×10倍,温度越低甲烷细菌数量越少. 相似文献
902.
Ou-Sup Han Masaaki Yashima Toei Matsuda Hidenori Matsui Atsumi Miyake Terushige Ogawa 《Journal of Loss Prevention in the Process Industries》2000,13(6):449-457
The structure of flame propagating through lycopodium dust clouds has been investigated experimentally. Upward propagating laminar flames in a vertical duct of 1800 mm height and 150×150 mm square cross-section are observed, and the leading flame front is also visualized using by a high-speed video camera. Although the dust concentration decreases slightly along the height of duct, the leading flame edge propagates upwards at a constant velocity. The maximum upward propagating velocity is 0.50 m/s at a dust concentration of 170 g/m3. Behind the upward propagating flame, some downward propagating flames are also observed. Despite the employment of nearly equal sized particles and its good dispersability and flowability, the reaction zone in lycopodium particles cloud shows the double flame structure in which isolated individual burning particles (0.5–1.0 mm in diameter) and the ball-shaped flames (2–4 mm in diameter; the combustion time of 4–6 ms) surrounding several particles are included. The ball-shaped flame appears as a faint flame in which several luminous spots are distributed, and then it turns into a luminous flame before disappearance. In order to distinguish these ball-shaped flames from others with some exceptions for merged flames, they are defined as independent flames in this study. The flame thickness in a lycopodium dust flame is observed to be 20 mm, about several orders of magnitude higher than that of a premixed gaseous flame. From the microscopic visualization, it was found that the flame front propagating through lycopodium particles is discontinuous and not smooth. 相似文献
903.
904.
韩静 《中国环境管理干部学院学报》2014,(3):40-43
清洁生产审核是实施清洁生产最有效的,也是最具可操作性的方法。在清洁生产审核预评估和评估阶段提出可行的无/低费方案,并按照"边审核边实施"的原则对所提的无/低费方案加以实施,能够使企业在短时间内达到"节能、降耗、减污、增效"的目的。以某化肥企业为例,找出企业存在的问题,评估企业的产排污情况,有针对性地提出了无/低费方案,并得以实施,为企业创造了一定的经济效益和环境效益。 相似文献
905.
906.
Sulphamethazine in poultry manure changes carbon and nitrogen mineralisation in soils 总被引:1,自引:0,他引:1
Yasser M. Awad Avanthi Deshani Igalavithana Young Han Lee Yeon-Kyu Sonn Adel R. A. Usman 《Chemistry and Ecology》2016,32(10):899-918
Antibiotics are newly emerging organic pollutants in manure, soil, vegetables and water. Animal manure application might be leading to the accumulation of antibiotics in the farmland. However, the effect of sulphamethazine (SMZ) on the soil microbial community was scarcely investigated. This study was aimed to evaluate the impact of SMZ on poultry manure, on the structure and function of microbial community, carbon mineralisation, and changes in nitrogen forms in soil via an incubation experiment lasting 56?d. The treatments consisted of poultry manure at 1% wt (PM), PM containing 20?mg?kg?1 SMZ (PM?+?20SMZ) and PM containing 100?mg?kg?1 SMZ (PM?+?100SMZ), along with the untreated soil (control). Solid phase extraction was performed to measure the SMZ concentration in soils using high-pressure liquid chromatography. The cumulative CO2-C was increased in all treated soils over the incubation period compared to the control. The PM?+?100SMZ had the highest increase in cumulative CO2-C from the soil at 56?d of incubation. The treatment of PM?+?20SMZ showed a short-term decrease in nitrification rate in the soils at 1?d by altering the microbial community composition with 17% dissimilarity and decreasing the abundance of bacteria compared to PM-treated soil. The PM?+?100SMZ increased C mineralisation in the soil. 相似文献
907.
908.
Ying Han Huiting Xie Wenbin Liu Haifeng Li Mengjing Wang Xuebin Chen Xiao Liao Nan Yan 《Frontiers of Environmental Science & Engineering》2016,10(6):7
We assessed the contamination levels of Mn, Zn, Cr, Cu, Ni, Pb, As and Hg and the risks posed by these potentially harmful elements in top-soils around a municipal solid waste incinerator (MSWI).We collected 20 soil samples, with an average pH of 8.1, and another fly ash sample emitted from the MSWI to investigate the concentrations of these elements in soils. We determined the concentrations of these elements by inductively coupled plasma–optical emission spectrometer (ICP-OES), except for Hg, which we measured by AF-610B atomic fluorescence spectrometer (AFS). We assessed the risks of these elements through the use of geoaccumulation index (I geo), potential ecological risk index (RI), hazard quotient (HQ i ) and cancer risk (Risk i ). The results showed that concentrations of potentially harmful elements in soil were influenced by the wind direction, and the concentrations of most elements were higher in the area northwest of the MSWI, compared with the area southeast of the incinerator, with the exception of As; these results were in accordance with those results acquired from our contour maps. According to the I geo values, some soil samples were clearly polluted by Hg emissions. However, the health risk assessment indicated that the concentrations of Hg and other elements in soil did not pose non-carcinogenic risks to the local populations. This was also the case for the carcinogenic risks posed by As, Cr, and Ni. The carcinogenic risk posed by As was higher, in the range 6.49 × 10–6–9.58 × 10–6, but this was still considered to be an acceptable level of risk. 相似文献
909.
农田土壤中铜的来源分析及控制阈值研究 总被引:4,自引:0,他引:4
农田土壤重金属污染直接危及到生态安全、食品安全和人体健康.从源头上控制农田土壤重金属污染是农业可持续发展和保障农产品质量安全的首要措施.本文采用物质流分析法与情景分析法,以水稻(双季稻、单季稻)、小麦-玉米、蔬菜(叶菜、根菜和果菜)的产地农田生态系统为研究对象,研究农田土壤中重金属铜的输入途径(大气沉降、磷肥、有机肥以及灌溉水)和输出途径(籽粒/可食部位、秸秆/残余物以及地表排水),并通过文献查阅和采样分析建立数据库,在平衡分析基础上为了保障100年土壤铜累积不超过设定的情景水平,当土壤铜背景值含量分别增加50%,100%和150%时,推导出磷肥、有机肥以及灌溉水的重金属含量安全阈值,磷肥中铜含量应控制在65~175 mg·kg-1范围内;畜禽粪肥中铜含量应控制在35~95 mg· kg-1范围内.灌溉水质标准应控制在40~70 μg·L-1范围内.这将为我国农产品产地安全管理和源头预防控制,保障我国农产品质量安全提供一定的技术指导作用. 相似文献
910.
Madeleine E. Hardus Han de Vries David F. Dellatore Adriano R. Lameira Steph B. J. Menken Serge A. Wich 《Behavioral ecology and sociobiology》2013,67(3):429-437
The diet of great apes consists of several hundred plant species. The factors determining diet differences have been examined between populations but not within a population, probably due to the confounding effect of seasonal fluctuations on fruit availability. In Sumatran orangutans (Pongo abelii), fruit availability appears to be sufficiently high year round to have little influence on diet composition, which in turn allows for addressing this question. We examined the diet of eight adult female orangutans at Ketambe, Sumatra, and investigated whether fig and non-fig fruit availability, association time, and/or home range measures influenced dietary overlap between female dyads. Between most pairs, females’ diets were different: 16 out of 23 pairs had a significantly low diet species overlap. Only fig diet overlap was influenced (negatively) by the availability of non-fig fruit. Association time only influenced (positively) fig diet overlap. Hence, orangutans gathered in fig trees when non-fig fruit availability was low. Home range measures did not influence overall diet overlap. To our knowledge, this is the first study showing that, while controlling for confounding factors, individuals with similar energetic requirements, from the same population and sharing the same area, make different dietary choices relatively to their preferred (non-fig) fruit constituting the majority of their diet. Social transmission, with putative matrilineal diet traditions, suitably explains these results. We discuss the implications of the findings for orangutan conservation, namely on reintroduction and the felling of fig trees. 相似文献