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筛选出2株真菌,产色链霉菌(Streptomyces chromogenes)和立枯丝核菌(Rhizoctonia solani)具有转化NO3^-的活性。它们的生比枯草芽孢杆菌(Bacillus subtilis)还强。产色链霉菌和立枯丝核菌将NH4^+转化为NO3^_的机理也不同于真菌尖孢镰刀菌(Fusariumoxysporium)必需有NO3^-或NO2^-的诱导才具有活性,它们可直接将硫 相似文献
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HydrolyticdynamicsofpesticideN'-(2,4-dimethylphenyl)-N-methylformamidineinaquaticsolution¥MoHanhong;YangKewu;AnFengchun;LiuYe... 相似文献
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辽河口营养要素的化学特性及其入海通量估算 总被引:14,自引:6,他引:14
本文根据1992年5月和8月辽河口水域营养要素的两次实测结果,讨论了溶解态无机氮(NO3^--N、NO2^--N、NH4^+-N)、活性磷酸盐(PO4^3--P)和活性硅酸盐(SiO3^2-Si)在辽河口水域的含量,分布特征,化学特性及其入海通量。结果表明:辽河口水域溶解态无机氮含量范围为12.13 ̄222.70μmol/L,活性磷酸盐含量范围为0.71 ̄2.81μmol/L,活性硅酸盐含量范围为 相似文献
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周苏平 《国外环境科学技术》1994,(3):45-50
在有氧和无氧条件下,利用罗曼光谱测定反应生成物的方法,研究了NO2和含SO^2-3溶液的反应机理,反应的生成物中含有NO-3,SO2-4和S2O2-5,反应的初始产物是NO-2离子和SO-3,基团:NO2+SO^2-3→NO^-2+SO^-3。SO^-3基团可以进行重组,或与氧反应生成SO-3基团。在无氧条件下,(SO^2-4)/(S2O^2-3)=1.8±0.3,反映SO^-3基团重组的反应如下 相似文献
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EffectofSO_2-pollutedrapeplantongrowthandreproductionoftheturnipaphid,Lipaphiserysimi(Kaltenbach)¥WuKunjun;GongPeiyu;LiXiuzhe?.. 相似文献
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应用人工神经网络对生物脱氮工艺进行预测并验证。采用工艺参数如COD、NO3-N、NO2-N、DO等作为输入节点,COD、NO3-N作为输出节点。结果显示神经网络能够较好地预报出水的水质参数。出水硝酸盐和COD预测结果与试验结果符合得较好,相对误差分别在10%和5%范围内。 相似文献
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不同电子受体对反硝化除磷菌缺氧吸磷的影响 总被引:11,自引:4,他引:7
利用厌氧/缺氧/好氧交替运行模式培养和富集反硝化除磷污泥,通过在缺氧段分别投加不同浓度的硝酸盐和亚硝酸盐,进行了反硝化除磷菌(DPB)在不同电子受体条件下的缺氧吸磷试验.结果表明,在保证有足够的硝酸盐电子受体的情况下,DPB的缺氧吸磷速率几乎不受硝酸盐浓度的影响,在试验条件下,缺氧阶段每消耗1 mg NO-3-N吸收约1 mg PO3-4-P;在一定浓度条件下,亚硝酸盐能够作为电子受体参与DPB反硝化吸磷,DPB在较低亚硝酸盐浓度(NO-2-N在5~20 mg/L范围)下的缺氧吸磷速率高于以硝酸盐为电子受体时的缺氧吸磷速率,并且缺氧吸磷速率在这个范围内随NO-2-N浓度的升高而降低;亚硝酸盐对DPB缺氧吸磷的抑制程度随其浓度的增加而增强,当NO-2-N≥35 mg/L时,DPB的缺氧吸磷反应几乎完全停止. 相似文献
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针对餐厨垃圾水解酸化液作外加碳源的反硝化脱氮效果进行研究,考察了人工配水条件下水解酸化液反硝化处理的适宜COD/NO3--N比范围,在适宜COD/NO3--N比条件下与甲醇、乙酸钠的反硝化效果进行对比,并验证了水解酸化液对于生活污水的反硝化效果.结果表明,人工配水条件下利用水解酸化液作碳源的适宜COD/NO3--N比为4.9~6.0,反硝化速率最高可达25.0mg NO3--N/(gVSS·h).反应过程存在2个不同的硝态氮去除速率阶段,并出现了亚硝氮积累.餐厨垃圾水解酸化液为含多种VFA成分的混合物,其反应过程中硝态氮的去除速率比甲醇、乙酸钠等纯物质做碳源时的硝态氮去除速率快.将餐厨垃圾水解酸化液用于生活污水脱氮处理,当COD/NO3--N比为6时,水中的硝态氮以及亚硝氮均能够得到较为彻底的去除. 相似文献
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利用综合筛选法从河流底泥中筛选出一株具有好氧反硝化能力的真菌,通过18S rDNA测序及形态观察,该菌被鉴定为链格孢属真菌。结果表明:该菌碳源底物利用范围广泛,能够利用多种有机碳源进行生长和反硝化。该菌对氨氮的去除主要通过该菌对氨氮的同化作用,而对亚硝酸盐和硝酸盐的去除是同化和反硝化共同作用的结果。当氨氮、亚硝酸盐和硝酸盐同时存在时,该菌优先利用氨氮,但对亚硝酸盐和硝酸盐并无明显的选择性。初始氮浓度和碳氮比对培养基pH和氮素的去除率均有一定的影响。当初始氮浓度和碳氮比合适时,该菌对3种氮素均有很高的去除效率,是一种具有应用前景的除氮菌属。 相似文献
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以某污水处理厂好氧曝气池为研究对象,利用N_2O和NO在线检测仪,监测好氧池不同空间位置处N_2O和NO的释放量,考察了氮素浓度、溶解氧及p H值对N_2O和NO释放量的影响.该污水处理厂好氧池DO浓度在0.24~1.12mg/L之间,且大多处于0.6mg/L左右,较低的DO导致NO2--N浓度沿水流推流方向不断积累;相应的,N_2O和NO释放量沿水流推流方向不断升高,并于好氧池末段达到最高值.NO释放NO2--N量与浓度显著正相关,N_2O释放量与NO2--N浓度也有一定的相关性,但没有NO显著.基于空间检测数据估算获得该污水处理厂N_2O释放量占进水NH_4+-N比例为6.34%~8.83%,NO释放量占进水NH4+-N比例为0.033%~0.034%. 相似文献
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《Atmospheric Environment. Part B. Urban Atmosphere》1990,24(1):87-92
Stone material from the corroding surface of buildings generally released nitric oxide with rates of 0.42–4.2 ng NON h−1 g−1 d.w. despite their large range of moisture, pH and content of ammonium, nitrite and nitrate. The net release rates of NO were independent of the NO mixing ratio of the atmosphere up to 1 ppmv NO. Whereas NO2 was taken up by all stones tested, uptake of NO was only observed in one out of five types of stone. NO release rates were highest at the stone surface and rapidly decreased in depth lower than 1 cm. NO release persisted for up to >3 months after the stone sample was removed from the building. NO was mainly produced during the biogenic oxidation of ammonium to nitrate at the stone surface which was probably due to endolithic nitrifying bacteria. Chemical decomposition of nitrite to NO and NO2 was only observed under acidic conditions. 相似文献
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厌氧氨氧化电子受体的研究 总被引:1,自引:0,他引:1
在无机条件下,以该课题组已经培养出来的厌氧氨氧化污泥作为接种污泥,分别以硫酸盐、硝酸盐和亚硝酸盐为电子受体来研究氨的氧化反应。从去除速率的角度来看,以NO2--N、NO3--N和SO42--S为电子受体的反应器,分别在运行的第24.5天、40天和31天时达到0.030 0 kg/(m.3d)NH4+-N去除速率,则氧化氨的能力由大到小依次是:亚硝酸盐>硫酸盐>硝酸盐;从标准吉布斯自由能变化来看,3种反应都是可以发生的;以亚硝酸盐为电子受体的反应过程是一个消耗酸度的生物过程,而以硫酸盐为电子受体的反应过程是一个消耗碱度的生物过程。 相似文献
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Two media bed (gravel and Filtralite NR) were tested in a mesocosm to evaluate the removal of organic matter (as chemical oxygen demand (COD)),ammonia (NH4-N),nitrite,nitrate and solid matter (as total suspended solids (TSS)) for a synthetic wastewater (acetate-based) and a domestic wastewater.The use of Filtralite allowed average removal rates (6–16.8 g COD/(m2·day),0.8–1.1 g NH4-N/(m2·day) and 3.1 g TSS/(m2·day)) and removal effciencies (65%–93%,57%–85% and 78% for COD,NH4-N and TSS,respectively),higher than that observed in the experiments with gravel.The applied loads of COD,ammonia,nitrate and TSS seem to influence the respective removal rates but only for the treatment of domestic wastewater with higher correlation coefficients for Filtralite.Regardless the type of media bed and the type of wastewater,nitrate was completely removed for nitrogen loading rates up to 1.3 g NO3-N/(m2·day).There was no evidence of the influence of nitrate loads on the removal of organic matter. 相似文献
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Evaluation of the e ectiveness of horizontal subsurface flow constructed
wetlands for di erent media
Two media bed (gravel and Filtralite NR) were tested in a mesocosm to evaluate the removal of organic matter (as chemical oxygen
demand (COD)), ammonia (NH4-N), nitrite, nitrate and solid matter (as total suspended solids (TSS)) for a synthetic wastewater
(acetate-based) and a domestic wastewater. The use of Filtralite allowed average removal rates (6–16.8 g COD/(m2 day), 0.8–1.1
g NH4-N/(m2 day) and 3.1 g TSS/(m2 day)) and removal e ciencies (65%–93%, 57%–85% and 78% for COD, NH4-N and TSS,
respectively), higher than that observed in the experiments with gravel. The applied loads of COD, ammonia, nitrate and TSS seem
to influence the respective removal rates but only for the treatment of domestic wastewater with higher correlation coe cients for
Filtralite. Regardless the type of media bed and the type of wastewater, nitrate was completely removed for nitrogen loading rates up to
1.3 g NO3-N/(m2 day). There was no evidence of the influence of nitrate loads on the removal of organic matter. 相似文献