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1.
设置了不同基质(砾石、加气混凝土)及是否种植美人蕉的不同人工湿地结构,通过小试实验对比各个工况对雨水径流污染的阻控效果.研究发现,加气混凝土与种植美人蕉的人工湿地组合成本略高(4.20元/工况),较其余工况高出1.00~2.90元/工况,但在运行的两个周期(交替运行30 h,落干48 h)内,对NH4+-N、NO3--N、TN、PO43-、TP和CODCr的平均去除率分别为73.3%、47.0%、85.4%、56.4%、76.0%和65.5%,平均高出其余工况10.9%~18.8%,效果最优,性价比最高,适于推广应用.  相似文献   

2.
从污水处理厂活性污泥中成功地筛选出一株自养型氢氧化细菌(Hydrogen-oxidizing Bacterium, HOB), 命名为Rhodoblastus sp. TH20。以模拟氨氮(NH4+-N)废水作为培养基, 该菌株能够以H2为能源, CO2为碳源, 其最适宜的生长条件为25℃、160 rpm和pH=7.0。当初始NH4+-N浓度为100 mg/L时, 菌株在72小时内能有效地去除NH4+-N (>99%)。其中, 77.8%的 NH4+-N被同化为有机氮, 储存在细胞体内, 剩余的转化为气态氮。 结果表明: Rhodoblastus sp. TH20具有高效的氨同化能力, 可实现NH4+-N向微生物蛋白的资源转化, 为含NH4+-N污水的资源化处理提供一条新途径。  相似文献   

3.
采用生物净化滤柱降低微污染水源水中的CODMn并去除NH4+-N、Mn2+,考察净化启动过程中以及沿程的CODMn、ρ(NH4+-N)、ρ(Mn2+)变化.结果表明,在71 d时,出水中的CODMn、ρ(NH4+-N)、ρ(Mn2+)均低于《生活饮用水卫生标准》(GB5749-2006),并且CODMn最先达标,生物除锰效果受到NH4+-N氧化过程中产生的NO2--N的影响.净化的沿程分析结果表明,随着净化启动的进行, CODMn的降低率和NH4+-N的去除率逐渐提高,稳定阶段CODMn、NH4+  相似文献   

4.
从冬季污水处理厂活性污泥中筛选出一株在低温及好氧条件下具有脱氮除磷功能的菌株,经16Sr DNA序列分析鉴定为不动杆菌,命名为Acinetobactersp.Z1.在10℃条件下探究菌株Z1的脱氮除磷性能及氮磷转化途径.结果表明,菌株Z1能够利用NH4+-N或NO3--N为唯一氮源,以及NH4+-N和NO3--N为混合氮源进行脱氮除磷.菌株Z1在碳源为乙酸钠,m(COD)/m(N)≥20,m(P)/m(N)=0.2,中性或弱碱性溶液中,摇床转速n≥100r/min的条件下具有良好的氮磷去除效果,NH4+-N和PO43--P最大去除率可分别达96.0%和97.9%.菌株Z1的氮转化途径主要是同化,同时也能通过异养硝化-好氧反硝化作用脱氮.菌株Z1可以在好氧条件下除磷,在厌氧条件下不释放磷.实验结果表明菌株Z1在低温条件下具有良好...  相似文献   

5.
采用垂直流和水平潜流人工湿地构成复合型人工湿地系统,对水产养殖废水进行处理,研究该复合型人工湿地系统对污水中TP、TN、NH_4~+-N和NO_2~--N的去除效果。结果表明:TP的去除率为82.45%至99.79%,平均去除率为92.75%;TN的去除率为74.09%至84.63%,平均去除率为79.33%;NH_4~+-N的去除率为35.27%至99.13%,平均去除率为67.84%;NO_2~--N的去除率为53.62%至75.98%,平均去除率为63.38%。该复合型人工湿地系统对TP去除率优于TN,并对重富营养化水体的净化效果优于异常营养化水体。  相似文献   

6.
为了进一步了解陕西关中地区大气氮沉降的变化特征,采用降水采集法对宝鸡2018年大气氮湿沉降进行了观测,并对雨水中可溶性无机氮浓度及沉降通量的动态变化进行了分析.结果表明:(1)雨水中NH4+-N和NO3--N月平均质量浓度为1.581 mg/L和1.369 mg/L,且降水量少的月份雨水中氮素浓度较高;(2)NH4+-N和NO3--N在雨水中的季浓度均呈现冬季高、夏季低的趋势;(3)大气氮湿沉降通量为9.728 kg/(hm2·a),其中NH4+-N和NO3--N分别占53.6%和46.4%,且降水量多的季节氮沉降通量也相应较高;(4)大气氮总沉降通量达23.713 kg/(hm2·a),约占当地农田氮肥施入的10%.  相似文献   

7.
针对滇池流域污染最严重的大清河,采用分段进水生物接触氧化工艺(SBCOP) 开展河道水体的旁路处理示范工程研究。SBCOP示范工程的设计规模为1000m3d,水力停留时间(HRT)为4.75h。2007年11月至2008年3月冬旱季期间,根据气候和进水水质条件调节分段进水比和气水比,示范工程共计运行了3 种工况。研究结果表明:SBCOP示范工程对COD和NH+4 - N 具有较好的去除效果,平均去除率为37.7%和32.9%,1∶1∶1的分段进水比利于去除COD 和NH+4 - N,NH+4 - N去除率随进水NH+4 - N浓度升高而降低;受到低温、低碳源、高进水DO浓度和生物膜生长不佳等因素影响,TN 去除效果较差,平均去除率为10.5%;TP的平均去除率为13.7%,由于示范工程未设排泥设施,TP的去除主要依靠底泥吸附和水绵吸收来实现,及时清除底泥和死亡的水绵利于去除TP 。进水为滇池湖水时,气水比为2∶1可以维持一定的去除效果。  相似文献   

8.
污水处理厂排水中氮、磷等营养盐浓度仍高于地表水,可能导致受纳水体富营养化,需要对其深度净化.周丛生物膜因其在脱氮除磷方面的优异性能而引起越来越多的关注.因此,设计了基于玄武岩纤维-周丛生物膜的连续流反应器(BFP-CFR),研究了不同水力停留时间(HRT)下BFP-CFR对污水深度净化的性能.研究结果显示,BFP-CFR的最佳HRT为48 h.该HRT下氨氮(NH4+-N)、总氮(TN)和总磷(TP)的去除率为79.88%、25.36%和94.83%.经过该反应器处理后,可显著降低污水氮磷污染物浓度.当HRT≥32 h时,氨氮出水浓度可达《地表水环境质量标准》(GB 3838-2002)Ⅳ类标准及以上,总磷浓度符合《地表水环境质量标准》(GB 3838-2002)Ⅱ类标准及以上.反应器出水水质和净化动力学分析表明,由于BFP反硝化能力弱,本反应器水质净化的限制性污染物为总氮,后续需要在促进反硝化功能以强化脱氮方面开展研究.这为今后将BFP运用于污水处理后排水的深度净化提供了数据支撑,指出了需要技术突破的方向.  相似文献   

9.
使用沸石对氨氮废水进行交换处理,沸石吸附氨氮(NHL4+-N)饱和后用NaCl溶液对其再生,研究再生前后沸石的交换穿透曲线。采用化学沉淀法对富含NH4+-N的再生液进行脱氯并考察其回收利用效果。结果表明:沸石对氨氯废水有很好的处理效果,再生沸石的动态交换穿透时间由60 min延长到160 mim;对沸石进行再生处理后的再生液经脱氮处理,得到NH4+-N质量浓度由141.6 mg/L降至12.65 mg/L。回收利用的再生液再生沸石的穿透时间延长到120 min。  相似文献   

10.
化肥厂高浓度氨氮废水的处理和回用   总被引:10,自引:0,他引:10  
在实验室规模研究了通过生成鸟粪石(磷酸铵镁, MAP)去除氨氮工艺条件的影响. 加入磷酸和MgO产生MAP沉淀, pH值对其影响很大, pH值为9.0时氨氮去除效果最好. PO43-, Mg2+, NH4+的摩尔比为1 ∶1.5 ∶1时, 氨氮去除率较大并且可较好地回收氨生成鸟粪石. 此外, 物料的加入次序严重影响氨氮的去除. 两步沉淀工艺氨氮去除率达99.1%, 氨回收率为80.1%.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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