Hydrothermal Synthesis of [ Mn5（H2PO4）2（PO4）2（H2O）4]Templated by Calixarene Under Mild Conditions

Meso-and microporous materials are of great in-terest from both the industrial and academic pointof view due to their catalytic , adsorbent , and ion-exchange properties .Inthis way,phosphates of tran-sition metals represent aninteresting group of materi-als owning to their channel structure .Calixarene are macrocyclic molecules in whichseveral phenolic units are linked via —CH2— or—S— bridges at their ortho positions . Calixarene-based receptors are among the most effective and se-lectiv…     

Synthesis and Characterization of a Novel Organic-Inorganic Hybrid Compound [Ni（DMF）6]3[PMo （12）O （40）]2

Inthelastfewyears,therehasbeenextensive researchinpolyoxometalates(POMs)fortheirstruc turaldiversityandpotentialapplicationinthefieldsof catalysis,biology,medicineandmaterialscience[1,2].POMs,whichareexcellentmolecularacceptors,can formnovelinorganic organiccomplexeswithanum beroforganicsubstratescontainingN,S,Oatoms.Inordertoimprovethephysicochemicalpropertiesof theorganic POMshybridmaterials,metalionscanbe introducedtothesystem.Organoamineisusually usedastemplateorstructure directingagen…     

Research on Nitrogen Removal and Microorganism in a Subsurface Flow Constructed Wetland System in Sihong County

1 Introduction As a new practical technology of treating wastewater, the constructed wetland system (CWS) is attracting more and more attention of investigators in China[1]. The packing medium, plants and microor- ganisms are the three main parts affecting the purifi- cation of constructed wetlands. Biological membranes of different biological phases exist on the surface of the packing medium and roots of plant distributed in the bed of the packing medium. It can purify waste- water by means…     

Synthesis and Structural Characterization of [Co（Q）2（H2O）2]（Q=8-Hydroxyquinoline Ion）

8-Hydroxyquinoline(HQ) and its derivatives areof the most intensivelyinvestigatedligands in the co-ordination chemistry[1 -3]. They have been used inmetallic ion detection,chromatography and especiallyin organic light-emitting diodes (OLEDS)[4]. Poly-oxometalates compounds have received muchattentionbecause of their potential applications in catalysis ,sorption, magnetism,photochemistry[5 ,6]. We origi-nally intended to gain the organic-inorganic hybridcomplex of HQ and polyoxometalates . …     

Two New Coordination Polymers: [M（phen）（e,a-cis-1,4-chdc）（H2O）]n（M=Mn and Cu; phen=1,10-phenanthroline; chdc=cyclohexanedicarboxylate）

1,4Cyclohexanedicarboxylicacid(1,4chdcH2)possessesachair typestructurewithcis andtrans conformations,soitcanconnectmetalionsindiffer entdirections.Hence,chdcmaybeagoodcandidate fortheconstructionofnovelcoordinationpoly mers[1-9].AsshowninFig.1[9],conformationAis Fig.1TransformsbetweenthedifferentconformationsofchdcH2theleaststableandisabletochangetoitsconformer Beasily.However,itisalittlemoredifficultwhenC becomesBbecausetheαprotonsshouldbedeproto natedtoacceleratetheequilibriumalthoughBi…     

Synthesis,Characterization and Formation Mechanism of Friedel’s Salt（FS:3CaO·A12O3·CaCl2·10H2O） by the Reaction of Calcium Chloride with Sodium Aluminate

The synthesis of Friedel’s salt(FS: 3Ca O·A12O3·Ca Cl2·10H2O) by the reaction of calcium chloride with sodium aluminate was investigated. Factors affecting the preparation of Friedel’s salt, such as reaction temperature, initial concentration, titration speed, aging time and molar Ca/Al ratio were studied in detail. XRD, SEM images and particle size distribution show that the reaction temperature, aging time and molar Ca/Al ratio have significant effect on the composition, crystal morphology, and average particle size of the obtained samples. In addition, the initial Ca Cl2 concentration and Na Al O2 titration speed do not significantly influence the morphology and particle size distribution of Friedel’s salt. With the optimization of the operating conditions, the crystals can grow up to a average size of about 28 um, showing flat hexagonal(or pseudohexagonal) crystal morphology. Moreover, two potential mechanisms of Friedel’s salt formation including adsorption mechanism and anion-exchange mechanism were discussed. In the adsorption mechanism, Friedel’s salt forms due to the adsorption of the bulk Cl- ions present in the solution into the interlayers of the principal layers, [Ca2Al(OH-)6·2H2O]+, in order to balance the charge. In the anion-exchange mechanism, the free-chloride ions bind with the AFm(a family of hydrated compounds found in cement) hydrates to form Friedel’s salt by anion-exchange with the ions present in the interlayers of the principal layer, [Ca2Al(OH-)6· 2H2O]+-OH-.     

A^2O工艺处理生活污水反硝化除磷研究

采用A2O工艺处理低ρ(C)/ρ(N)实际生活污水,研究其脱氮除磷性能和反硝化除磷特性.试验结果表明:处理低ρ(C)/ρ(N)实际生活污水时,在不设置预缺氧区、无外加碳源的情况下,A2O工艺的脱氮除磷能力受到严重影响,出水ρ(NO3--N)高达35 mg/L,TN平均去除率仅为47.1%;此时A2O工艺除磷能力较差,缺氧段有释磷现象的发生.当设置预缺氧区后,A2O工艺的脱氮除磷能力明显提高,TN平均去除率可达60.7%,PO43--P平均去除率为55.9%;此时系统存在反硝化除磷现象,缺氧段除磷率为31.4%～46.9%.在设置预缺氧区的基础上,通过外加碳源,提高进水ρ(C)/ρ(N),可进一步提高系统的脱氮除磷能力,TN平均去除率可达74.4%,出水ρ(PO34--P)小于0.5 mg/L,缺氧段除磷率高达66.2%～90.9%.同时研究了外加碳源情况下污泥内PHA成分、含量及糖原含量在A2O系统内的沿程变化趋势.经过驯化、富集,反硝化聚磷菌相对于全部聚磷菌的代谢活性从31.1%提高到74.7%.A2O工艺反硝化除磷能力的增强,提高了碳源的利用效率.     

Factors affecting biological denitrifying dephosphatation in anaerobic/anoxic/aerobic sequencing batch reactor

This study was conducted to verify and discuss the denitrifying dephosphatation under different levels of nitrate concentration and retention time of anoxic/aerobic process in a Sequencing Batch Reactor (SBR). The results of tests demonstrated that there were two kinds of phosphorus-accumulating organisms (PAOs) in the biological excess phosphorus removal (BEPR) system. One was non-DNPAOs that could only use oxygen as terminal electron acceptors, the other was denitrifying PAOs (DNPAOs) that could use both nitrate and oxygen as terminal electron acceptors. Phosphorus uptake efficiency could be attained under anoxic period ranging from 28.7%-96.7% in an anaerobic/anoxic/aerobic system. Experimental results showed that nitrate concentration and retention time of anoxic/aerobic process were the key factors affecting the course of denitrifying dephosphatation.     

论间歇式活性污泥法的自动控制

本文简单地介绍了间歇式活性污泥法（ＳＢＲ法）污水处理系统的特点、它本身所具有的独特优点及在运行管理中存在的问题。指出实现ＳＢＲ法的自动控制是进一步推广这一工艺的必要条件。为了使ＳＢＲ法的运行更安全可靠，尽可能节省运行费用，应当逐步实现ＳＢＲ法的有机物浓度控制。     

采用氧化沟从城市污水中去除氮和磷的研究

氧化沟作为一种经济而有效的污水处理技术已被广泛应用，然而，传统的氧化沟工艺对氮和磷的去除效率较低。在该研究中通过调节曝气转刷的充氧能力，使氧化沟内形成好氧和缺氧段，总氮去除率越过９０％。为了提高氧化沟的除磷效率，在氧化沟系统内加入厌氧池，使总磷去除提高了２０％左右。试验结果表明，采用氧化沟工艺从城市污水中去除氮和磷是可行的。     

组合工艺对农村生活污水中氮磷的去除效果

利用“厌氧生物反应器＋潜流复合型人工湿地”组合工艺处理农村生活污水中氮和磷。厌氧生物反应器和潜流复合型人工湿地水力停留时间分别为24和48h,进水总氮、氨氮和总磷分别为10．3～51．8mg／L、6．8～44．7mg／L和0．9～5．2mg／L,组合工艺对总氮、氨氮和总磷的平均去除效率分别为30．7％、42．9％和72％,不同季节处理效率为：夏季〉春季〉冬季。组合工艺中的COD主要由厌氧水解酸化、基质截留、微生物代谢而被去除,氮主要由人工湿地微生物作用和植物吸收被去除,磷主要由人工湿地基质吸附被去除。系统整体脱氮效果的提高可采用在厌氧生物反应器后增加充氧装置,提高污水中的溶解氧,通过增强人工湿地中的硝化能力来实现。     

多环反应器在低碳源条件下强化脱氮除磷效果

通过对多种连续流除磷脱氮工艺的时空分析,集成并构建了一种多环反应器处理系统,在此基础上,通过正交试验,找出了在低碳源条件下影响污水脱氮除磷效果的重要因素,提出了低碳源条件下生物除磷脱氮的适宜工艺控制参数,为类似条件的污水处理工艺设计和运行提供了参考.     

过量储存-SND作用脱氮特性及机理研究

对序批式生物膜法工艺中所表现出来的脱氮特性进行了探讨,并提出了过量储存-SND脱氮作用机理,厌氧段脱氮主要靠生物膜对含碳氮有机物的过量储存作用;好氧段脱氮主要靠生物膜的SND作用,反硝化的有机碳源主要为生物膜中在厌氧段过量储存的有机碳源.     

适合中小城镇生活污水脱氮除磷工艺的研究

水体富营养化现象已成为人类面临严重的水环境问题之一 ,降低废水中氮和磷含量是防止水体富营养化的主要任务。软性填料淹没式生物膜序批式 (SBR)处理工艺 ,可使COD去除率达90 %以上 ,BOD去除率可达98 %以上 ,氮去除率75 %以上 ,磷的去除率可达90 %左右。是适合中小规模城镇生活污水脱氮除磷行之有效的技术之一。     

内循环对Orbal氧化沟系统生物脱氮除磷的影响

试验采用实际生活污水,利用改进的Orbal氧化沟中试系统(其中,氧化沟主体容积460L),在低溶解氧条件下研究了内循环对系统的影响,实现了良好的脱氮除磷效果.增加内循环回流比,可以增强系统对氨氮负荷的抗冲击能力,提高脱氮效果,但是除磷效率降低.考虑COD、氮和磷等指标,控制系统内循环回流比为1,可得到良好的处理效果.对系统进行物料平衡计算,结果表明,聚磷菌约吸磷0.18 mg P/mg COD,与文献值接近.试验发现,系统中存在着反硝化聚磷菌(DPAOs),其比吸磷速率为13.2 mg P/(g VSS·h),根据缺氧与好氧比吸磷速率之比计算DPAOs约占总PAOs数量的23%.     

序批式MBBR中反硝化聚磷菌的选择与富集

采用序批式移动床生物膜反应器(MBBR),研究了以硝酸盐为电子受体的反硝化聚磷菌(DPB)的选择和富集.结果表明,采用3个阶段进行选择和富集,DPB占全部聚磷菌(PAOs)比例约从11.77%提高到66.07%;第3阶段培养末期,COD和TP去除率平均值分别为68.78%和69.02%,缺氧所耗ρ(NO₃^--N)达到23.91 mg/L;对反应器中生物膜进行直接染色发现,在厌氧放磷阶段能观察到聚磷菌体内有大量聚-β-羟丁酸(PHB)出现,而在缺氧吸磷阶段则有大量聚磷颗粒(Poly-p)出现,故可尝试采用聚磷生物膜的直接染色方法观察聚磷微生物细胞内PHB和Poly-p颗粒的变化,来判断生物除磷过程及效果.