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1.
研究了孔石莼对不同浓度养殖废水的水质净化效果.结果表明,孔石莼对水体中氮、磷营养盐的清除效果明显:对NO3--N、NO2--N、NH4+-N、PO43--P移除率分别可达99.8%、99.6%、95.9%、98.7%;对总无机氮的移除率可达98.6%.孔石莼在吸收氨氮同时对硝态氮和亚硝态氮也有吸收,但NH4+-N的吸收大部分在第1天完成,而NO3--N和NO2--N的大部分吸收需要2 d或3 d完成.孔石莼在养殖废水中生长良好,鲜质量逐日增加,日生长率均较大.  相似文献   

2.
在低基质质量浓度条件下,对海绵填料生物膜反应器和颗粒污泥反应器进行厌氧氨氧化的脱氮性能进行对比研究。研究结果表明:当进水NH4+-N和NO2--N质量浓度分别为(17.03±2.16)mg/L和(19.17±2.33)mg/L时,颗粒污泥厌氧氨氧化反应器的脱氮性能明显优于海绵填料生物膜反应器的脱氮性能;保持对NH4+-N和NO2--N的平均去除率为90%以上时,通过缩短水力停留时间,颗粒污泥反应器容积氮去除速率可达3.55 kg.N/(m3·d),而海绵填料生物膜反应器仅为0.94 kg·N/(m3·d);进水中NO2--N与NH4+-N的质量浓度比能影响反应器的化学计量关系。  相似文献   

3.
SBR反应器实现半亚硝化的启动策略   总被引:2,自引:0,他引:2  
由于碳源不足,传统脱氮工艺难以处理高NH4+-N低碳氮比废水,采用短程硝化与厌氧氨氧化相结合的工艺可以处理此类废水,而半亚硝化是上述组合工艺的先决条件.采用低溶解氧和半碱度为启动策略,实现SBR反应器的半亚硝化作用,以期为后续厌氧氨氧化反应器提供合适进水水质.实验结果表明:水温(26±1)℃,控制初始碱度和NH4+-N的摩尔比为1,进水pH保持7.5±0.1,溶解氧为(0.8±0.2)mg/L的条件下,可将NO2--N累积率维持在95%,且出水中NO2--N和NH4+-N浓度相近,而NO3--N质量浓度低于5mg/L,反应器成功启动.进水化学需氧量(COD)对半亚硝化效果几乎没有影响.一个运行周期内三氮及COD的变化趋势说明,采用半碱度策略控制半亚硝化进程是可行的,能够保证出水NO2--N/NH4+-N摩尔比约为1.  相似文献   

4.
以2013年1月和6月实测数据为参考,分析赣江水体氨态氮( NH4+-N)、硝态氮( NO3--N)和总磷( TP)分布特征和污染来源。结果表明:赣江水体枯水期的NH4+-N和NO3--N平均质量浓度高于丰水期,但不具有统计学意义;枯水期的TP平均质量浓度显著高于丰水期。 NH4+-N在赣州和南昌市区下游出现极大值;枯水期干流NO3--N质量浓度在赣州和南昌市区下游较高,丰水期干流浓度相差不大,支流中桃江和袁水NO3--N质量浓度明显偏高;枯水期赣江TP质量浓度在赣州市和南昌市下游出现高值区,丰水期只在赣州市下游出现高值区。通过赣江氮磷营养盐的时空分布特征以及与Cl-质量浓度的相关性得出,赣江NH4+-N污染主要来源于城市污水排放;NO3--N在枯水期主要来源于城市污水排放,丰水期则来自农业污水和城市污水的共同作用;TP主要来源于城市污水排放,其次为农业污水影响。  相似文献   

5.
好氧颗粒污泥膜生物反应器处理畜禽废水   总被引:2,自引:0,他引:2  
采用好氧颗粒污泥膜生物反应器处理畜禽废水,分别对COD、NH4 -N、NO2--N、NO3--N的去除效果和对膜通量的影响进行了研究。结果表明:在水力停留时间(HRT)为8h,进水COD浓度为600mg/L,NH4 -N浓度为40mg/L的条件下,出水COD、NH4 -N的浓度分别为46.6和4.8mg/L。NO2--N和NO3--N的去除率也可达90%以上。并且好氧颗粒污泥的加入减缓了膜的污染。  相似文献   

6.
稻田生态系统可以有效减少流入水体的农业面源污染物.本文通过模拟试验,研究了不同施肥时间(常规施肥时间和在此基础上提前一个半月施肥)以及在不同耕作模式(垄作、平作)下稻田生态系统对田面水中无机态氮的消纳效果.结果表明:稻田生态系统能够有效降低田面水中无机态氮、全磷的含量.与灌水第1d相比,灌水14d后,所有稻田田面水中NH4+-N浓度平均下降84.3%,灌水21d后,所有稻田田面水中NO3--N浓度平均下降64.6%,TP浓度下降58.0%;提前施肥条件下稻田生态系统对田面水中无机态氮具有更好的吸附、消纳效果,灌水后的第1d,所有稻田田面水中NH4+-N浓度均出现最高值,其中,常规时间施肥和提前施肥NH4+-N质量体积浓度分别为2.52和1.28mg/L,灌水后的第3d,常规时间施肥稻田田面水中NO3--N质量体积浓度上升至最大值5.92mg/L,而此时提前施肥稻田约为3.65mg/L;不同耕作模式对无机态氮消纳的影响差异不显著.  相似文献   

7.
研究土壤氮分布特征对合理预测云杉林生态系统结构与功能具有重要作用,采用PVC管移植法,以祁连山东段青海云杉(Picea crassifolia)林区土壤为研究对象,采用野外取样法和室内分析法,对土壤全氮、铵态氮(NH4+-N)、硝态氮(NO3--N)进行测定分析,重点分析祁连山哈溪林区土壤氮在不同海拔、不同植被、不同剖面上的变化,以及温度、水分与土壤氮之间的关系,旨在提高祁连山青海云杉林生产力及水源涵养能力。结果表明:该区土壤平均含水量为58.9%,平均容重为0.695g/cm3;含水量随海拔的升高有波动增大趋势,容重随海拔的升高有波动下降趋势;不同植被类型的含水量和容重分别表现为灌丛云杉草地;草地云杉灌丛。铵态氮随海拔的升高有缓慢降低趋势,全氮和硝态氮均随海拔的增大有缓慢增加趋势,三种氮在海拔上的变异系数(CV)分别为19.2%、8.48%、12.6%,可见TN、NO3--N属于中等变异,NH4+-N属于弱变异。NH4+-N和NO3--N在剖面上的变异系数分别为17.3%和9.9%,基本上都为中等变异,NH4+-N在剖面上的变化为线型趋势,线性方程为Y=-2.15X+17.42,r2为0.89;NH3--NN在剖面上呈多项式变化趋势,线性方程为Y=1.205X2-5.085X+12.5,r2为1。土壤水分、容重与NH4+-N和NO3--N之间均有三次函数关系,表现为土壤容重和铵态氮在表层有较显著的拟合关系,其r2为0.843,P0.05;水分和铵态氮在20-40cm有较强的显著性,其r2为0.61,P0.05;水分和硝态氮在20-40cm有较显著的变化关系,其相关系数r2为0.653,P0.05,其他各层显著性不强。  相似文献   

8.
应用两级上流式厌氧污泥床(UASB)-缺氧/好氧(A/O)-序批式反应器(SBR)深度处理早期和晚期垃圾渗滤液.首先在一级UASB(UASB1)中实现反硝化,在二级UASB(UASB2)中通过产甲烷降解有机物,在A/O反应器的好氧区进行NH4+-N的硝化,最后在SBR中去除残余NH4+-N及通过反硝化去除NO2--N和NO3--N深度脱氮.试验结果表明:早期渗滤液ρ(COD),ρ(TN)和ρ(NH4+-N)分别为14.8,1.8和1.3 mg/mL,最终出水ρ(TN),ρ(NH4+-N),ρ(NO2--N)和P(NO3--N)分别为28,4,3.4和1.9 mg/L,获得了大于98%的TN和NH4+-N去除率.晚期渗滤液ρ(COD)为2.5 mg/mL;ρ(TN),ρ(NH4+-N)分别为3.0和2.9 mg/mL时,获得99%以上的TN和NH4+-N去除率.最终出水ρ(NH4+-N),ρ(NO2--N)和P(NO3--N)都小于10 mg/L,最终出水ρ(TN)为26~32 mg/L.  相似文献   

9.
通过有机玻璃土柱盆栽试验,研究了包膜肥料在水稻不同生育期对不同深度土层的土壤渗滤液中NO2--N、NO3--N、NH4+-N含量的影响。结果表明,土壤渗滤液中NO2--N、NO3--N、NH4+-N质量浓度随着水稻的生长逐渐降低;在水稻分蘖期和拔节期,随着土壤深度的增加NO2--N、NO3--N含量呈现先减小后增大的趋势,NH4+-N含量呈现先增大再减小再增大的趋势;在水稻抽穗期和成熟期,NO2--N、NO3--N含量呈现逐渐减小的趋势,NH4+-N含量呈现增大的趋势。在水稻生育期内与施用普通尿素UR相比,包膜肥料LP40、LPSS、SC60氮素渗滤损失总量分别降低了58.27%,46.38%,33.30%。  相似文献   

10.
针对高浓度含氮废水亚硝化SBR工艺,进行了动力学模型研究,建立了NH4 -N浓度变化模型、NO2--N浓度变化模型和NO3--N浓度变化模型.通过试验对动力学模型进行了预测与评价,结果表明:以动力学方程式(尤其是NH4 -N浓度变化的模型、NO2--N浓度变化的模型)计算的理论值与实测值结果基本吻合,对高浓度氨氮废水亚硝化SBR工艺的设计和运行具有一定的指导意义.  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.
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   

15.
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   

16.
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   

17.
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   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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   

20.
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   

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