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821.
生物三相流化床处理COD废水工艺条件研究 总被引:2,自引:0,他引:2
采用生物三相流化床处理含Cu-COD废水,研究了载体的选择和生物挂膜条件、及废水停留时间、容积负荷、气水比、温度和pH值等工艺条件与COD去除率的关系。结果表明,在控制适宜条件下,对于含Cu2~3mg/l,COD 1500~2500mg/l的染化行业废水,采用生物流化床法处理,排放水Cu可达0.52~0.82mg/l,COD为145~175mg/l,COD去除率可达92%~93%。 相似文献
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1IntroductionAccordingtothetraditionalstudiesoflandscapeecology,fragmentationiscausedbycorridorsorsomeelongatedpatchesphysica... 相似文献
823.
在TiO2催化剂上苯酚光催化氧化反应研究2-多相光催化氧化与直接光解反应的比较 总被引:14,自引:0,他引:14
在TiO2悬浆体系,中压汞灯作用下,通过苯酚降解过程中总碳浓度变化及二氧化碳生成速度的变化规律,研究了光催化氧化与直接光解反应的不同,并着得比较了当反应条件如催化剂量,气相氧浓度以及光强度变化对两种反应的影响。实验结果证明了两种反应的历程和产物各不相同,多相光催化氧化更有利于有机物分子的降解,而光解作用会引起聚合反应,同时也说明充分利用太阳能不仅是开发光催化水处理技术的重要途径,也是抑制直接光解加 相似文献
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Keshan disease (KD) occurs in a wide geographic belt stretching from the Heilongjiang Province in northeastern China to Yunnan Province in southwestern China, including Huangling County, Shaanxi Province. In order to research relationships between eco-environmental geochemistry and KD pertaining to Se, Mo, B, Zn, Mn, and Cu, this investigation was conducted in the Jiantou KD area in Huangling County, one of the areas in China where the incidence of KD is highest. Environmental samples (rock, soil, plant and childrens hair) were collected from the area. Se in plants is low, ranging from 0.03 to 0.06 µg Se g–1 in corn, potato and soybean. Se contents in childrens hair are normal or reach the limitation of dangerous level. This study reports 0.18 µg Se g–1, B <40 µg g–1, and Mo <1.0 µg g–1 in aeolian soil, 0.14–0.38 µg Mo g–1 and 3–8 µg B g–1 in corn and potato (daily staple food for local human beings in the area). The Jiantou KD area is one where the elements Se, Mo and B are deficient. It is proposed that the deficiency of elements Se, Mo and B may be involved in the pathogenicity of KD with respect to the eco-environmental system because Se, Mo and B are essential micronutrients for plants and human beings. It seems that there is no significant relationship between the Zn–Mn–K–Pb–Ba associations and KD. 相似文献
828.
The generation rates and emission factors of particulate matter and associated polycyclic aromatic hydrocarbons (PAHs) from incense burning were assessed in a laboratory setting. The differences among different segments of the same stick, among different sticks of the same kind of incense, and between two kinds of manually made Chih-Chen incense sticks (A and B) were evaluated. Joss sticks were burned inside a 44 cm long elutriator; personal environmental monitors fitted into the top of the elutriator were used to take PM2.5 and PM10 samples of incense smoke. Samples were analyzed for PAHs by gas chromatography-flame ionization Detector. It was found that particle and associated PAHs were generated approximately at 561 microg/min (geometric standard deviation (GSD) = 1.1) and 0.56 microg/min (GSD = 1.1) from Incense A, and at 661 microg/min (GSD = 1.7) and 0.46 microg/min (GSD = 1.3) from Incense B, respectively. One gram of Incense A emitted about 19.8 mg (GSD = 1.1) particulate matter and 17.1 microg (GSD = 1.2) particulate-phase PAHs, while one gram of Incense B produced around 43.6 mg (GSD = 1.1) of particles and 25.2 microg (GSD = 1.2) of particle-bound PAHs. There were significant differences in emissions between Incenses A and B, although they belong to the same class of incense. A 10-20% variability in emissions was observed in the main part of the manually produced stick, and a larger variation was found at both tips of the combustible part. 相似文献
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