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1.
研究了小型开放系统中不同浓度的铵氮对微囊藻生长的影响.在4个分别命名为N1、N2、N3、N4的水箱中,除铵氮浓度不同,其它的条件基本一致,且正磷酸盐设为足量,达到1.65mg·L-1,4个水箱中铵氮浓度分别为5.23mg·L-1,12.43mg·L-1,22.5mg·L-1,37.28mg·L-1,结果表明,铵氮浓度小于2.54mg·L-1时对微囊藻的生长起抑制作用;当浓度在7mg·L-1~15mg·L-1时,微囊藻呈暴发性生长;高于19.25mg·L-1的铵氮抑制微囊藻的生长.  相似文献   

2.
杏林湾水库水质富营养化评价   总被引:2,自引:0,他引:2  
以1999年12月至2000年10月杏林湾水库调查资料为基础,利用浮游植物群落指标、营养状态指数和理化参数指标对杏林湾水库的营养水平进行评价.结果表明,杏林湾水库浮游植物密度年均达3456.77×104个/L,平均TSI为67,杏林湾水库属于蓝-硅藻型富营养型水库.  相似文献   

3.
以三峡库区瀼渡河库湾为研究对象,连续五年逐月监测水体硝态氮、氨态氮、叶绿素a浓度.采用spearman秩相关系数法分析水体富营养化与硝态氮、氨态氮的关系,结果显示硝态氮与富营养化呈负相关,氨态氮则与富营养化无显著意义,由此表明三峡库区支流库湾水体硝态氮是藻类等浮游植物繁殖吸收的主要价态氮.  相似文献   

4.
亚硝酸盐反硝化脱氮   总被引:3,自引:0,他引:3  
利用单纯形优化法获得了从亚硝酸盐反硝化脱氮的工艺条件为 :pH8.3,温度 2 8℃ ,C/N比1.6 ,泥 /水比为 0 .32 ,在此条件下能够稳定、高效地处理高浓度的含氮废水 (NO2 - -N〈35 0mg·L- 1) ,其脱氮速率高达 16 2mg·L- 1·h- 1,脱氮率 >99%。  相似文献   

5.
设计厌氧消化-化学混凝-SNAD联合工艺对海产品加工中的高浓泡药间废水进行处理.厌氧消化对废水中COD去除率最高可达94.37%,平均可达89.77%,有机氮与聚合磷转化为NH+4-N、PO3-4-P,浓度分别达总氮、总磷浓度的85%~90%;20 g·L-1的聚合氯化铝可实现总磷浓度1 000 mg·L-1废水的总磷去除率99.83%,出水磷浓度为1.70 mg·L-1.SNAD系统中控制温度为32~35 ℃,以空气流量10~15 mL·min-1间歇曝气(ton/toff=10 min/5 min)控制DO为0.1 mg·L-1左右,pH为7.5~8.0,HRT为24 h,运行稳定时最高可处理总氮浓度为655 mg·L-1的废水,总氮、COD去除率分别为72.71%、56.70%.高通量测序结果表明反应器内形成了SNAD系统,AOB、AnAOB和DNB含量分别为2.72%、2.09%、1.46%.  相似文献   

6.
ICEAS反应器处理城市污水的试验研究   总被引:2,自引:0,他引:2  
对ICEAS工艺的处理效果进行了研究,结果表明,ICEAS既能去除污水中的有机物,还能达到脱氮除磷的效果,出水COD浓度为15 2~42 2mg·L-1,COD总去除率可达80%~88%;出水BOD5浓度为5 12~16 90mg·L-1,总去除率可达85%~93%;出水氨氮浓度为4 5~7 5mg·L-1,总去除率为60%~70%,磷的去除率为60%~75%.  相似文献   

7.
胶州湾胶体有机碳、氮和磷的初步研究   总被引:1,自引:0,他引:1  
1997年至 1998年间在青岛胶州湾对海水中的胶体有机碳、氮和磷进行了初步研究。胶体有机碳 (COC)的浓度范围为 33.9~ 5 4 .0 μmol·L-1,约占总溶解有机碳的 31%。在总溶解氮和磷中 ,胶体氮和磷均以有机物的形式存在 ,胶体有机氮 (CON)的浓度范围为 2 .13~ 4 .5 1μmol·L-1,平均 3.0 7μmol·L-1,约占总溶解有机氮 (DON)的 31%。胶体有机碳、氮、磷季节变化幅度并不很大 ,表明胶体物质在水体中输入和输出大体处于平衡状态。  相似文献   

8.
两级SBR工艺处理小城镇生活污水研究   总被引:1,自引:0,他引:1  
采用两级 SBR (sequence batch reactor)工艺处理小城镇生活污水 ,试验结果表明 ,先通过 SBR1反应器对污水起到了平衡、均化作用 ,再通过 SBR2反应器实现了污水的脱氮除磷 .试验出水 ρCOD(铬法 )浓度为 2 1~ 43 mg· L-1,去除率达到 85 %~ 93 % ;出水ρ(N) (N为氨态氮 )为 3 .3~ 9.5 mg· L-1,去除率达到 65 %~ 81 % ;出水ρt(P)为 0 .3 2~ 0 .63 mg· L-1,去除率达到 87%~ 95 % .  相似文献   

9.
生态滤池污水处理过程中氮形态变化及平衡研究   总被引:2,自引:0,他引:2  
污水经生态滤池(MEEF)处理后,出水中化学耗氧量(COD)、生物需氧量(BODs)、总氮(TN)和总磷(TP)的质量浓度降低,氮的形态构成与进水有较大差异.水力负荷分别为1.0 m3·m-2·d-1和2.0 m3·m-2·d-1时,进水中NH4 -N的平均质量浓度分别为45.8和35.7 mg·L-1,出水中分别降为10.3和20.0 mg·L-1;进水中NO3--N的平均质量浓度分别为0.24和0.2 mg·L-1,出水中分别增加到30.4和4.1 mg·L-1.进水中硝态氮占总氮的0.3%,在两种水力负荷下出水中硝态氮占出水总氮的比例分别增加到52.7%和12.8%,说明水力负荷降低有利于硝化作用进行.还对氮的质量平衡进行了估计,并讨论了MEEF的工作原理.  相似文献   

10.
河北省中南部农区地下水硝态氮含量特征分析   总被引:1,自引:0,他引:1  
于2005和2006年沿横贯河北省中南部的北纬38°带,分别在低山丘陵、山前平原、低平原和近滨海平原冬小麦夏玉米轮作农区,采集灌溉机井水样分别为24,120,71和44个,并分析水样中的硝态氮含量.结果显示,河北省中南部农区浅层地下水硝态氮总体上达到了饮用水标准,没有发生大面积污染,但硝态氮含量空间变异很大;地下水埋深及施肥量对地下水硝态氮含量都有明显的影响;低山丘陵区硝态氮含量最高,平均含量为13.39 mg/L;山前平原区含量其次,平均含量为4.03 mg/L;低平原及近滨海平原区含量最低,平均为0.41 mg/L;低山丘陵和山前平原部分样点硝态氮含量超过饮用水标准,地下水污染明显,需要采取防治措施.  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.
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   

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

19.
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   

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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