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1.
沸石改性吸附氨氮的试验研究   总被引:8,自引:0,他引:8  
比较了在不同改性条件下沸石对氨氮的去除效果,结果表明:NaCl改性效果明显,6%盐溶液浓度改性沸石氨氮去除率可达95.3%;酸浸改性沸石吸附性能明显优于碱浸改性沸石;在2h的浸泡时间下,酸溶液浓度升高,改性沸石的氨氮吸附效果降低.  相似文献   

2.
沸石分子筛因其特殊的结构特性对氨氮具有较高的吸附性能.将天然斜发沸石在250℃下高温改性,并用于含氨氮溶液的等温吸附处理,获得了在不同氨氮初始质量浓度下的改性沸石等温吸附曲线.根据朗格缪尔吸附理论拟合得到改性沸石的等温吸附方程1/qe=7.589 86/Ce+0.137 39,并求得其对氨氮的理论最大吸附量qm为7.278 6 mg/g.通过对沸石曝气生物滤池系统在不同水力负荷和气水比条件下的运行研究,总结出改性斜发沸石作为曝气生物滤池工艺的最佳水力负荷为0.15~0.25m3/(m2.h),气水比为20∶1.  相似文献   

3.
通过实验考察了沸石粒径、投加量、废水pH和吸附时间对NaCl改性沸石去除废水中氨氮的影响,结合单因子实验和正交实验获得优化条件组合,并在优化组合条件下,将NaCl改性沸石去除氨氮效果在实际废水中进行验证.结果表明,粒径越小越利于NaCl改性沸石对废水中氨氮的去除,而投加量、废水pH和吸附时间亦对改性沸石去除氨氮产生影响,通过正交优化实验分析得出,最主要影响因素为沸石投加量,结合单因子实验,筛选出改性沸石去除废水中氨氮的最佳工艺组合条件为沸石粒径60目、沸石投加量70g/L、废水pH=6、吸附时间1h,废水中氨氮去除率达到90.5%.在最佳工艺组合条件下,NaCl改性沸石对生活污水、养猪废水和化工工业废水中氨氮的去除率分别为91.67%、91.65%和89.31%,与在模拟废水中的去除率基本一致.这为改性沸石的进一步实际应用奠定了基础.  相似文献   

4.
有机改性沸石覆盖抑制底泥氮磷释放的效果   总被引:2,自引:0,他引:2  
制备了十六烷基三甲基铵(HDTMA)有机改性沸石,研究了该改性沸石覆盖底泥对底泥中氮磷释放的影响及机理,结果表明:①当HDTMA负载量为沸石外部阳离子交换容量(ECEC)的207%时,有机改性沸石吸附磷酸盐的效果最佳;最佳负载量条件下的有机改性沸石,对磷酸盐的吸附能较好地符合Langmuir等温吸附方程,饱和吸附量为0.644 mg.g-1,常数K为0.295 L.mg-1;pH值对有机改性沸石吸附磷酸盐的性能有显著影响,随着pH值的增加对磷酸盐的吸附能力逐渐增强;共存阴离子(NO3-,HCO3-和SO42-)的存在会抑制有机改性沸石对磷酸盐的吸附.②最佳HDTMA负载量条件下有机改性沸石对氨氮的吸附作用符合Langmuir等温吸附方程,饱和吸附量为13.0 mg.g-1,常数K为0.011 9 L.mg-1,且与天然沸石相比单位质量改性沸石的吸附量降低了20%左右.③有机改性沸石覆盖可以有效地抑制底泥氨氮的释放,但有效抑制底泥氨氮释放的持续时间与天然沸石相比缩短了1/5;有机改性沸石覆盖抑制底泥磷释放的效率与天然沸石相比大大加强,且投加的有机改性沸石越多,对底泥磷释放的抑制效果越好.  相似文献   

5.
改性天然沸石的制备及对氨氮的吸附   总被引:20,自引:0,他引:20  
在不同温度及超声辐射条件下,用NaCl溶液浸泡天然沸石来对其进行表面改性,以强化其对氨氮的吸附.应用静态吸附法分别测定了氨离子在天然沸石和美国产Champion、中国台湾产AZOO沸石和改性沸石上的吸附离子交换等温线,并探讨了溶液pH值、焙烧温度和浸泡方法对沸石吸附氨氮的影响.研究结果表明:天然沸石吸附氨氮的最佳pH值范围在3~9之间,吸附过程以离子交换作用为主;高温焙烧会引起沸石脱水,从而导致孔壁坍塌,使沸石孔径增大,比表面积减小,降低了对氨氮的吸附交换能力;经98℃NaCl溶液浸泡后,沸石中Na 的含量增加,沸石对氨氮的吸附交换容量明显增大,超过了美国产Champion沸石和中国台湾产AZOO沸石.  相似文献   

6.
改性沸石去除微污染水中氨氮的试验   总被引:1,自引:0,他引:1  
采用壳聚糖和氢氧化钠对天然沸石进行了改性,制备了新型改性沸石,并采用吸附-混凝的处理方法,对微污染水中氨氮的去除进行了试验研究. 通过扫描电镜和能谱分析对沸石进行了表征;考察了吸附时间、pH、氨氮初始质量浓度和沸石投加质量浓度等因素对氨氮去除效果的影响. 结果表明,在氨氮初始质量浓度为2.51 mg·L-1的微污染水中,投加质量浓度为1 g·L-1的改性沸石,氨氮去除率达到70.8%,更适用于现有的自来水工艺.  相似文献   

7.
以景观水体为研究对象,将沸石进行盐、盐+热、盐+碱和盐+酸复合改性,研究其对废水中氨氮去除效果的影响.结果表明,利用最佳质量浓度为3%的NaCl改性沸石进行除氨氮实验,当反应吸附时间为60min时,对氨氮的去除率可达80%;再对NaCl改性沸石在500℃下煅烧2h ,当吸附时间为30min时,氨氮去除率高达95%.其去除率较NaCl改性沸石提高1.19倍,较天然沸石提高1.73倍.  相似文献   

8.
承德沸石改性处理氨氮废水及其吸附容量的研究   总被引:4,自引:0,他引:4  
通过盐改性、碱热熔-碱水热改性、加热活化等方法对承德沸石进行改性处理,用模拟氨氮废水进行了吸附实验,并采用XRD和SEM对其改性效果及原因进行了分析.通过对比去除效率发现:采用质量分数为7%的NaCl溶液改性的沸石最适合于处理氨氮废水.同时测量了天然沸石吸附氨氮的饱和吸附容量,并比较等温吸附曲线后认为Freundlich曲线有更好的符合性.  相似文献   

9.
天然沸石对生活污水中氨氮和总磷的吸附能力有限,本文采用一系列的改性方法,去除沸石内部杂质,改善沸石的吸附效果.通过实验结果分析,盐碱浸渍结合高温灼烧沸石的吸附效果最好,改性条件是Na OH溶液浸渍浓度是0.5 mol/L,Mg Cl2溶液浓度为1 mol/L,灼烧温度设定为105℃,此时改性沸石对氨氮的去除率为86.5%,总磷的去除率为37.2%,相对于天然沸石氮磷的去除率分别提高了34.9%和15.1%.但是,沸石改性对于氨氮的吸附效果较好,对总磷的去除效果还有待提高.本文提供了一种降低污水中氮磷浓度的方法,为污水的深度处理提供依据.  相似文献   

10.
改性沸石去除氨氮和有机物的研究   总被引:27,自引:0,他引:27  
研究了不同改性条件下 ,沸石去除氨氮和有机物的效果 .试验着重考察有机物对去除氨氮的影响以及钙离子对氨氮和有机物去除效果的影响 .结果表明 ,改性沸石对氨氮有很好的去除效果 ;酸浸沸石的处理效果明显优于碱浸沸石 ;当有机物含量较高时 ,会降低去除氨氮的效果 ;酸浸沸石对有机物有一定的去除效果 ,而碱浸沸石去除效果很差 ;水中钙离子的存在 ,在一定程度上会降低氨氮的去除效果 ,但同时提高有机物的去除效果 ;沸石主要去除大相对分子质量的有机物 ,对小相对分子质量的有机物去除效果很差 .  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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