不同基质高负荷垂直流人工湿地水力特性研究

以沸石、无烟煤、页岩、蛭石、砾石、陶瓷滤料、高炉钢渣、生物陶粒等8种基质为材料,在1 000—2 500 mm/d的高水力负荷条件下,研究了不同基质在垂直流人工湿地模拟柱中运行1年的水力学特性和系统堵塞动态。结果表明:基质系统的水力停留时间和水头损失可间接反映湿地堵塞状况;基质自身结构与其水力学特征密切相关。生物陶粒、高炉钢渣和沸石3种基质分别填充的系统内部水头损失较小、水力停留时间短、堵塞不明显;砾石、蛭石堵塞较为严重。通过对不同基质的含水率和孔隙率的分析发现,基质的高含水率(如蛭石)有利于垂直流人工湿

无根萍、酵母菌和红螺菌的水质净化和抑藻作用

从2005年9月到2005年10月,利用莲花湖中的3个49m2,深度为1.5m的围隔进行生物水质净化和除藻研究。1#围隔为对照,2#围隔水体中加入无根萍,3#围隔水体中喷洒酵母菌和光合细菌。与1#围隔比较,2#围隔水面的无根萍的数目在300L×5×103 L-1,3#围隔的喷洒复合菌数目酵母菌(300L×4×105L-1)和红螺菌(300 L×8×108 L-1)。本实验结果表明:在30 d内,2#和3#围隔中的TP分别下降40%、25%;TN分别下降43%、16%;叶绿素含量分别下降51%、31%。透明

不同生态工程及其组合系统除藻效率的比较研究

比较了不同水力负荷条件下,由水平流碎石床湿地、下行流湿地、上行流湿地、好氧塘和兼性塘等不同生态工程单元组合而成的5组8套小型处理系统对藻类的去除效率及其变化趋势,并根据适宜水力负荷下各系统除藻效率的季节变化研究了各种组合形式对藻类的去除效果.结果表明:当水力负荷为0.8m3/(m2.d)时,各处理单元对藻类生物量的去除效率均达到最高;好氧塘+下行流湿地系统和水平流碎石床系统均表现出较强的抗水力冲击负荷能力;各生态工程组合系统的除藻效率在夏季最高,对藻类的去除率均超过94%;冬季最低,藻类去除率变动范围为3

复合垂直流人工湿地污水处理系统硝化与反硝化作用

研究了复合垂直流人工湿地各基质层的硝化与反硝化菌数量以及硝化与反硝化作用强度 .结果表明 ,基质中硝化菌数量为 7 5× 10 3 ～ 1 1× 10 5MPN·g-1,反硝化菌数量为 7 5× 10 6～ 1 1× 10 7MPN·g-1.硝化作用强度为 0 0 1～ 6 35 μg·(g·d) -1,反硝化作用强度为 3 37～ 4 19μg·(g·d) -1.沿水流方向硝化菌数量和硝化作用强度明显降低 ,其变化趋势呈显著正相关 (r =0 96 6 1,p <0 0 0 1) .反硝化菌数量和反硝化

长江天鹅洲故道江豚的集群规模及其时空分布

2 0 0 1年 5月至 2 0 0 2年 4月 ,选择使用岸上定点观察、流动观察和水上流动观察 3种观察方式 ,对长江天鹅洲故道内约 2 0头江豚的集群状况进行了一个周年的监测 ,共观察到江豚集群 5 88次。结果表明 :天鹅洲故道内江豚以集群的方式迁移和活动 ,集群规模从 2— 2 0头不等 ,一般分成 2个 9— 11头规模的亚群体 ,2个亚群体活动范围相对独立 ,其活动主要为D区和H区。每个亚群体又常分成规模较小的核心群体 ,其中 3头集群最多。一年中春、秋和冬季江豚集群状况基本相同 ,而夏季有所

利用底栖动物监测严家湖农药污染

本文报道了严家湖氧化塘建成前后底栖动物群落变化,共发现寡毛类12种,水生昆虫幼虫15种,软体动物8种,其他动物2种。讨论比较3种监测方法:(1)依据底栖动物群落结构各大类的比例,提出了六级标准;(2)用群落的多样性指数,由Shannon和Weaver的公式计算,并结合化学数据比较,提出D=0,D<1,D=>1—2,D=>2—3.5,D=>3.5—5,D>5六级评价;(3)用底栖动物的残留物积累,分析不同污染带的动物(Limnodrilus hoffmeisteri,Glyptotendipes sp.,B

EFFECTS OF LOW-TEMPERATURE AND PHYSIOLOGICAL AGE ON SUPEROXIDE-DISMUTASE IN WATER HYACINTH (EICHHORNIA-CRASSIPES SOLMS)

Superoxide dismutase activity in water hyacinth leaves was not sensitive to small changes in environmental pH, but declined markedly with greater pH changes. KCN inhibited superoxide dismutase activity, suggesting that the enzyme was mainly composed of the Cu-Zn form. Low temperature (2-degrees-C) treatment caused a decline in superoxide dismutase activity. This effect became more pronounced as the treatment time was prolonged. Furthermore, the decline was much more significant than reductions of glucose-6-phosphate dehydrogenase activity or respiration under comparable conditions. With increasing physiological age, superoxide dismutase activity declined and was significantly lower in old than in young leaves. Therefore, superoxide dismutase activity might be employed as one of physiological parameters in studying leaf senescence.

Mode Characteristics for Square Resonators With a Metal Confinement Layer

Microsquare resonators laterally confined by SiO2/Au/air multilayer structure are investigated by light ray method with reflection phase-shift of the multiple layers and two-dimensional (2-D) finite-difference time-domain (FDTD) technique. The reflectivity and phase shift of the mode light ray on the sides of the square resonator with the semiconductor/SiO2/Au/air multilayer structure are calculated for TE and TM modes by transfer matrix method. Based on the reflection phase shift and the reflectivity, the mode wavelength and factor are calculated by the resonant condition and the mirror loss, which are in agreement well with that obtained by the FDTD simulation. We find that the mode factor increases greatly with the increase of the SiO2 layer thickness, especially as d < 0.3 mu m. For the square resonator with side length 2 mu m and refractive index 3.2, anticrossing mode couplings are found for confined TE modes at wavelength about 1.6 mu m at d = 0.11 mu m, and confined TM modes at d = 0.71 mu m, respectively.

草地植被恢复对次降雨土壤水分动态的影响分析

通过对宁南典型草原植被恢复过程次降雨土壤水分动态的研究,阐明植被恢复对次降雨后土壤水分的影响及机理。结果表明,次降雨提高了土壤含水率和贮水量,均表现出1 d>3 d>7 d。草地封育能够提高次降雨资源化效率,随封育时间延长,次降雨后0-60 cm土壤含水率和0-100 cm土壤贮水量不断提高。降雨对封育草地土壤水分的影响范围在100 cm土层内,100 cm以下不能得到降雨的补充。封育时间延长土壤水分活跃层加深,坡耕地仅为40 cm,封育17 a后达到60 cm。土壤持水能力越强,表层土壤饱和导水率越大,雨后1 d在0-100 cm土壤贮水量越大。地上生物量愈大,雨后1~7 d在0-200 cm土壤耗水量越大。

稀土离子在硼铝酸盐及相关基质中的VUV-Vis范围发光性质

PDP(等离子平板显示器)是一种最有前途的大屏幕壁挂式彩电,而它需要VUV激发下的高效荧光粉,同时由于VUV荧光粉也是无汞荧光灯的需求,所以研究VUV激发的稀土激活的荧光粉是实际应用的需要.对于光谱分析该工作采用了理论计算与光谱数据分析相结合的方法,对所测光谱各个谱峰进行了详细的指认.得到了以下的结论和成果:1.得到了大量的含氧酸盐中稀土离子的VUV光谱数据.2.首次系统地应用两种方法预测了三价稀土离子的f-d跃迁位置,并首次系统地通过计算预测了三价稀土离子在含氧酸盐中的电荷迁移带的位置.3.首次实验观察到Ce<'3+>的电荷迁移带,观察到了Tb<'3+>的电荷迁移带.4.在所有含Dy<'3+>的样品中都观察到Dy<'3+>的f-d跃迁.5.LaPO<,4>和ABLa(PO<,4>)<,2>(A=K,Na;B=Mg,Zn)基质中,观察到了Ce<'3+>的5个f-d跃迁,指认了Tb<'3+>的5个f-d跃迁,指认了掺杂Ce、Tb的VUV光谱中的所有谱峰.6.对所研究基质中的稀土离子的f-d跃迁和电荷迁移带进行了系统地预测和指认.7.通过总结不同稀土离子在相同基质中的VUV光谱,并参考文献的相关报导,总结了所研究基质的基质吸收位置.8.通过Eu<'3+>的灾光探针作用和ce<'3+>的发射光谱等,确证三价稀土离子在La<,2>CaB<,10>O<,19>基质中同时取代了八配位的Ca<'2+>和十配位的La<'3+>,占据了两种格位.9.合成了一种新型绿色长余辉材料,具有亮度高,余辉时间长,可用日光激发等优点.10.合成了一种UV激发下性能优异的掺Eu<'3+>的红色荧光粉,亮度可以跟商业红粉Y<,2>O<,3>:Eu相比拟,而基质材料与Y<,2>O<,3>相比降低了成本.

聚合物载体缩硫醛大环螯合剂的合成和选择络合汞的性能以及做为高分子汞解毒促排药物的动物实验

在我国某些地区，汞的污染已达到十分严重的程度。如，第二松花江吉林市下游江段，江水总汞含量和鱼体含汞量已能和日本严重汞污染的水俣湾相比。在化学工业，仪表工业中，汞中毒列为严重性占第二位的职业病。因此，汞的污染防治已是急待解决的问题。各种含硫螯合剂可应用于含汞污水处理及汞中毒的治疗。Nyssen等1976年合成了一种缩聚型的缩硫醛大环螯合树脂，作者希望它能成为汞中毒的口服解毒药物。这种产物对Hg~(++)和CH_3Hg~+表现了极强的选择络合性能。但是由于其交联结构不利于Hg~(++)深入树脂内部，因此络合容量太低，仅为2毫克Hg~(++)/克。为了提高其络合能力并进而得到一种水溶性产物，我们合成了二种新的高分子缩硫醛大环螯合剂；其一，以聚苯乙烯为载体的缩硫醛大环螯合剂（简写为PS-S）。其二，以右旋糖苷为载体的缩硫醛大环螯合剂（简写为D-S）。前者做为螯合树脂表现了对Hg~(++)极强的选择络合能力，并且络合容量比缩聚型产物高十倍以上（达30-60毫克Hg~(++)/克）。后者经动物实验证明是一种无毒而有效的高分子汞解毒药。（一）PS-S的合成和络合性能1）醛基的引入采用了不同交联度的凝胶型聚苯乙烯（PS）树脂及不同孔径和表面的大孔型PS树脂做为骨架材料，并采用了二种不同的方法在PS上联结醛基。2）PS-S的合成采用了一系列巯基化合物与PS-CHO反应合成PS-S。例如，用乙二醇二巯基乙酸酯与PS-CHO反应，其它采用的巯基化合物还有：丁二醇二巯基乙酸酯、季戊四醇四巯基乙酸酯、乙硫醇、巯基乙酸、巯基乙酸乙酯等。同一骨架材料的上述各产物的静态Hg~(++)络合容量基本相同，可是含硫环的大小对络合容量影响不大。3）缩硫醛化产物模型化合物的研究合成了几种小分子缩硫醛化产物，对它们进行了MS、NMR谱分析，从以上三种不同类型的缩硫醛化产物本身及其对Hg~(++)作用物的稳定性比较，以第二类大环型产物稳定性最好。4）不同骨架结构的PS-S络合性能比较对不同交联度的凝胶型PS树脂为骨架的PS-S树脂，及不同孔经和比表面积的大孔型PS树脂为骨架的PS-S树脂，分别测定了对Hg~(++)的络合容量，结果表明：大孔型PS-S树脂络合容量最高。当其孔径在100-1000埃，比表面积100米~2/克时，静态络合容量可达65毫克Hg~(++)/克。5）大孔PS-S树脂络合性能的研究①研究了不同测定方法下（静态法、动态法、饱和法），不同测定条件（如树脂用量、Hg~(++)溶液浓度等）对产物络合容量测定的影响。在PS-S装柱反复络合洗脱十次后，树脂络合容量不下降。②不同PH测定PS-S络合容量表明：中性条件下对Hg~(++)络合容量较高。某些有机溶剂（如乙醇、二氧六环）加入Hg~(++)水溶液有利于络合容量的提高。而某些有机溶剂（如丙酮、乙酸）的添加却降低了树脂络合容量。③大孔PS-S树脂对不同金属离子(Pb~(++)、Co~(++)、Cd~(++)、Ca~(++)、Zn~(++))络合容量的测定表明：大孔PS-S树脂对Hg~(++)的络合容量比上述其它金属离子高几十倍到近千倍。（二）D-S的合成与性能研究了介质、温度、时间、反应物用量等条件对反应结果的影响，反应所用Dextran分子量31600，生成的D-CHO含醛基量0.66毫克当量/克。生成的D-S含硫量3.5～6%，分子量约3600。（三）PS-S和D-S对汞中毒巯基酶的解毒实验生物体汞中毒的一个重要毒理是汞使巯基酶中毒，我们采用了PS-S和D-S来对汞中毒的巯基酶-脲酶解毒，使失活的脲酶重新恢复活力，模拟药物在生物体内的解毒过程。实验表明：PS-S和D-S的解毒能力比相同重量的离子交换树脂、巯基树脂、巯基棉等都要强。而且很少量的PS-S和D-S就能使脲酶100%的恢复活力。不同用量的PS-S和D-S使汞中毒脉酶恢复活力的试验显示了良好的线性关系，尤其是D-S，它几乎等当量地（每二个硫原子络合一个汞原子）使汞中毒脲酶恢复活力。（四）D-S的汞解毒及代谢促排过程的同位素示踪试验1）当给小白鼠静脉注射极限注射量（达1毫升/只鼠）的6%D-S水溶液时未发生受试动物的死亡，即LD_(50) > 4000毫克/公斤体重，说明D-S是无毒的。同时病理镜检表明动物肝肾此时无异常。2）分别对10只小白鼠静注致死量的Hg~(++)，对其中一组注射D-S（0.2毫升/只）一次，结果3小时后对照组动物全部死亡时，给药组尚存活6只。D-S表面了对受试动物良好的保护作用。病理镜检表明D-S使肾脏的汞中毒病变有所缓解。3）用同位素~(125)I标记D-S，研究了口服，静注D-S在小白鼠体内的代谢情况。试验得到了D-S经静注，口服二种途径在小白鼠体内血、肝、肾、脾等主要脏器中的经时代谢曲线。六小时后D-S大部分代谢出体外，12天后全部代谢出体外。并进而得到了二种不同给药方式的药物代谢动力学方程。D-S口服为：C_血=0.1 (e~(-0.00183t)-e~(-0.01t))符合于一级吸收过程的单室模型 D-S静注为：C_血=0.384 e~(-0.645t) + 0.074 e~(-0.08t) + 0.042~(-0.00464t)符合于快速静注下的三室模型。4）采用~(203)Hg做了D-S口服、静注给药时对Hg~(++)的促排作用的实验，得到了二种给药方式下Hg~(++) 在小白鼠血、肝、肾、脑及全身的促排代谢经时曲线。实验表明D-S对汞有明显促排作用，其中口报组效果更好。D-S促排与代谢同位素示踪试验数据之间表现了有趣的相关性，有助于我们解释D-S对汞促排的机制。动物实验表明：D-S可能成为一种临床使用的副作用小的汞中毒解毒促排新药。

Period-doubling bifurcations of the thermocapillary convection in a floating half zone

This study experimentally explored the fine structures of the successive period-doubling bifurcations of the time-dependent thermocapillary convection in a floating half zone of 10 cSt silicone oil with the diameter d (0)=3.00 mm and the aspect ratio A=l/d (0)=0.72 in terrestrial conditions. The onset of time-dependent thermocapillary convection predominated in this experimental configuration and its subsequent evolution were experimentally detected through the local temperature measurements. The experimental results revealed a sequence of period-doubling bifurcations of the time-dependent thermocapillary convection, similar in some way to one of the routes to chaos for buoyant natural convection. The critical frequencies and the corresponding fractal frequencies were extracted through the real-time analysis of the frequency spectra by Fast-Fourier-Transformation (FFT). The projections of the trajectory onto the reconstructed phase-space were also provided. Furthermore, the experimentally predicted Feigenbaum constants were quite close to the theoretical asymptotic value of 4.669 [Feigenbaum M J. Phys Lett A, 1979, 74: 375-378].

尼泊尔水东哥、水麻、木姜冬青和青荚叶的化学成分研究

活性筛选中发现尼泊尔水东哥 (Saurauia napaulensis DC.) 树皮95%乙醇提取物具有α-淀粉酶抑制活性、水麻(Debregeasia orientalis) 枝叶95%乙醇提取物显示血管紧张素转化酶(ACE)抑制活性、青荚叶(Helwingia japonica (Thunb.) Dieter.) 95%乙醇提取物的中小极性部分显示蛋白酪氨酸磷酸酯酶(PTP)1B抑制活性。为全面了解它们的成分及相关活性成份，主要运用硅胶柱层析方法从这三个植物分离得到39个化合物，通过波谱分析或与已知品对照的方法对其进行了鉴定。对木姜冬青(Ilex litseaefolia Hu et Tang)的成分做了进一步的研究，取得了如下结果。 1. 从尼泊尔水东哥树皮的95%乙醇提取物分离并鉴定12个化合物： auranamide、aurantiamide benzoate、齐墩果酸、β-谷甾醇、β-胡萝卜甙、乌苏酸、2α,3α-二羟基-12-烯-28-乌苏酸、2α,3β,24-三羟基-12-烯-28-乌苏酸、(2S,3S,4R,10E)-2-[(2'R)-2' -hydroxytetracosanoylamino] -10-octadecene -1,3,4-triol、 2α,3α,24-三羟基-12-烯-28-齐墩果酸、2α,3β-二羟基-12-烯-28-乌苏酸和2α,3α,24-三羟基-12-烯-28-乌苏酸。 2. 从水麻枝叶的95%乙醇提取物分离并鉴定了18个化合物：棕榈酸、二十烷酸、二十烷酸甲酯、β-谷甾醇、Monogynol A、桦木酸、Hederagenin、β-胡萝卜甙、18αH-19(29)-烯-3-酮-乌苏烷、3，4-开环-20(30)-烯-乌苏烷-3-酸、Pomolic acid，表儿茶素、儿茶素、槲皮素、槲皮素-3-O-β-D-吡喃葡萄糖苷、紫丁香苷、紫丁香酚苷和山萘酚-3-O-芸香糖。儿茶素、槲皮素和槲皮素-3-O-β-D-吡喃葡萄糖苷为具有ACE抑制活性的成分。 3. 从木姜冬青95%乙醇提取物的乙酸乙酯部分分离并鉴定了5个化合物： 2-O-β-D-吡喃葡萄糖-6,2´-二羟基-4,4´-二香草酰氧甲基-1,1´-二苯醚（冬青苷）和四个已知化合物：七叶内酯、香草酸、3,4-二甲氧基苯乙酸和vanilloylcalleryanin。冬青苷为新化合物。 4. 从青荚叶95%乙醇提取物的中小极性部分分离并鉴定了9个化合物：β-谷甾醇、β-胡萝卜苷、羽扇豆醇、桦木醇、桦木酸、棕榈酸甘油酯、桂皮酸、6αH-4-烯-3-酮-豆甾醇和6βH-4-烯-3-酮-豆甾醇。 5. 对1985-2006年间天然二苯醚类化合物及活性研究进展进行综述. The in vitro test indicated that the 95% ethanolic extract of the barks of Saurauia napaulensis DC showed α-amylase inhibitory activity, the 95% ethanolic extract of the whole plants of Debregeasia. orientalis showed angiotensin converting enzyme (ACE) inhibitory activity and some fractions of the 95% ethanolic extract of the aerial parts of Helwingia japonica showed protein tyrosine phosphatase (PTP)1B inhibitory activity. In order to investigate components and active compounds of the three plants, they were chemically studied mainly using. Thirty-nine compounds were isolated predominantly by column chromatography identified by spectral methods or comparing them with authentic samples. Further investigation of Ilex litseaefolia Hu et Tang was carried out. Major results are as follows: 1. Twelve compounds were isolation from the 95% ethanolic extract of the barks of S. napaulensis DC. They were identified as auranamide, aurantiamide benzoate, oleanolic acid, β-sitosterol, β-daucosterol, ursolic acid, 2α,3α-dihydroxyurs-12-en-28-oic acid, 2α,3β,24-trihydroxyurs-12-en-28-oic acid, (2S,3S,4R,10E)-2-[(2'R)-2'-hydroxytetracosanoyl amino]-10-octadecene-1,3,4-triol, 2α,3α,24 -trihydroxyolean-12-en-28-oic acid, 2α,3β-dihydroxyurs-12-en-28-oic acid, and 2α,3α,24-trihydroxyurs-12-ene-28-oic acid, respectively, by spectral methods or comparing them with authentic samples. 2. Eighteen compounds were isolation from the 95% ethanolic extract of the whole plants of D. orientalis. They were identified as palmitic acid, henicosanoic acid, henicosanoic acid methyl ester, β-sitosterol, monogynol, betulinic acid, hederagenin, β-daucosterol, 18αH-urs-20(30)-en-3-one, 3,4-seco-urs-20(30)-en-3-oic acid, pomolic acid, (-)-epicatechin, (+)-catechin, quercetin, quercetin 3-O-β-D-glucopyranoside, syringin, syringiaresinol digloside and kaempferol-3-O-rutinose. (+)-Catechin, quercetin and quercetin 3-O-β-D-glucopyranoside were the ACE inhibitory active components. 3. Further phytochemical investigation of the ethyl acetate parts of 95% ethanolic extract of the whole plant of I. litseaefolia afforded 2-O-β-D-glucopyranose-4,4´-di-vanilloyloxymethyl-2,6´-dihydroxy-1,1´-diphenyl ether (ilexiside), esculetin, vanillic acid, 3,4-dimethoxybenzylacetic acid and vanilloylcalleryanin. Ilexiside was new compound. 4. Nine compounds were isolation from the 95% ethanolic extract of the whole plant of H. japonica: β-sitosterol, β-daucosterol, lupeol, betulin, betulinic acid, glycerol monopalmitate, cinnamic acid, stignast-4-en-6β-3-one and stignast-4-en-6α-3-one 5.Diphenyl ether compounds from nature between 1985-2006 were summarized.

垃圾渗滤液场外硝化－原位反硝化脱氮协同填埋场温室气体减排

垃圾卫生填埋是国内外城市垃圾的主要处置方法。垃圾渗滤液是渗入填埋场垃圾的降水混合垃圾降解过程中产生的物质而形成的混合物，是垃圾填埋场向环境排放的主要污染物。渗滤液由于其所含高浓度有机和无机污染物，且其中很多物质有生物毒性或难生物降解，难于治理。特别是到填埋晚期，渗滤液中高浓度的氨氮更是增加了治理的难度。渗滤液场外硝化－原位反硝化是填埋场氮管理的新途径。本文利用从环境中筛选出优势硝化功能菌对渗滤液中的高浓度氨氮进行生物硝化，经硝化后的渗滤液回灌至以垃圾柱模拟的生物反应器填埋场，在填埋场内实现原位反硝化。 上述目标通过以下两部分来实现： 第一部分：渗滤液场外硝化。首先从污水厂的硝化污泥中富集并筛选出硝化功能菌，在模拟氨氮废水中优化。将驯化的硝化功能菌接种于连续式完全混合反应器（CSTR）进行高氨氮渗滤液硝化研究。在200余天的连续运行中，反应器硝化和有机物去除效果良好。在最大氨氮负荷和有机物负荷分别为0.65 g N l-1 d-1 和3.84 g COD l-1 d-1时，氨氮和COD去除率分别高于99%和57%。实验过程中发现，游离氨（FA）和溶解氧（DO）浓度对反应器中亚硝酸盐的积累影响很大。 第二部分：渗滤液原位反硝化。本文利用一个垃圾填充柱模拟生物反应器填埋场，研究了硝化渗滤液回灌对垃圾降解的影响，和回灌的硝化渗滤液中TON（总氧化态氮）对填埋场生物反应器产甲烷作用的影响。最后利用变性梯度凝胶电泳（DGGE）分析了硝化渗滤液回灌对垃圾填埋场菌群结构的影响。结果表明：回灌的TON被完全还原，反硝化为主要反应，最大TON负荷为28.6 mg N kg-1 TS d-1。当垃圾柱TON负荷大于11.4 mg N kg-1 TS d-1时，出现了产甲烷抑制，抑制作用随TON负荷的增加而加强。在此过程中，反硝化逐渐代替产甲烷作用成为填埋场内垃圾降解的主要反应，且更多产生的是清洁的氮气，而非温室气体甲烷。直到实验结束时，回灌硝化渗滤液的垃圾柱的甲烷产量仅相当于对照的2.5%，并且回灌的硝化渗滤液还加速了填埋场垃圾的降解与稳定。通过DGGE进行菌群结构分析发现，由于TON对填埋场的长期作用，反硝化菌增多而产甲烷菌减少。 Landfill still remains the chief method for MSW management around the world. Leachate is a mixture of rainfall permeating through landfill and organic and inorganic matters generated during decomposition of the wastes in the landfills, characterized as highly complicated and refractory wastewater. Ex-situ nitrification and sequential in-situ denitrification represents a novel approach to nitrogen management at landfills. In the present paper, nitrification was carried out in a continuous stirred tank reactor (CSTR) inoculated with nitrifying bacteria which were isolated from municipal WWTP of Chengdu city. The nitrified leachate from CSTR was recirculated to a lab-scale municipal solid waste (MSW) column where in-situ denitrification took place. The above object was achived through two parts as following: First, ex-situ nitification of leachate. After acclimated in simulated wastewater for 3 month, nitrifying bacteria isolated from WWTP nitrifying sludge were added to the CSTR for nitrification. The results over 200 days showed that the maximum nitrogen loading rate (NLR) and the maximum organic loading rate (OLR) was 0.65 g N l-1 d-1 and 3.84 g COD l-1 d-1, respectively. The ammonia and COD removal was over 99% and 57%, respectively. Moreover, the effects of free ammonia (FA) and dissolved oxygen (DO) on nitrification were investigated. Second, in-situ denitrification was studied in a municipal solid waste (MSW) column. Variation of nitrified leachate and its effects on the decomposition of municipal solid waste (MSW) were studied in a lab-scale MSW column to which nitrified leachate was recirculated. Additionally, DGGE was employed to investigate the microbial community of both MSW columns. The results suggested: complete reduction of total oxidized nitrogen (TON) was obtained with maximum TON load of 28.6 mg N kg-1 TS d-1 and denitrification was the main reaction responsible. Methanogenesis inhibition was observed while TON load was over 11.4 mg N kg-1 TS d-1 and the inhibition was enhanced with the increase of TON load. Denitrification gradually took over methanogenesis to become the main reaction responsible for decomposition of MSW while nitrogen gas, a clean byproduct, was generated instead. Till the end of the experiment, the average weekly methane production in the denitrification column was as low as 2.5% of that of the control, and the rate of decompition and stability of MSW was accelerated by the recirculation of the nitrified leachate.Owing to long term exposure of nitrified leachate to landfill, denitrifying bacteria increased and methanogen decreased.