75 resultados para Organic compounds Properties Synthesis.


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Perfluorinated organic compounds (PFOCs) are emerging persistent organic pollutants (POPs) widely present in the environment, wildlife and human. We studied the cellular toxicology of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) on oxidative stress and induction of apoptosis in primary cultured hepatocytes of freshwater tilapia (Oreochromis niloticus). Cultured hepatocytes were exposed to PFOS or PFOA (0, 1, 5, 15 and 30 mg L-1) for 24 h, and a dose-dependent decrease in cell viability was determined using trypan blue exclusion method. Significant induction of reactive oxygen species (ROS) accompanied by increases in activities of superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) were found, while activities of glutathione peroxidase (GPx) and glutathione-S-transferase (GST) were decreased. Glutathione (GSH) content was reduced following treatment of PFOA and PFOS. A dose-dependent increase in the lipid peroxidation (LPO) level (measured as maleic dialdehyde, MDA) was observed only in the PFOA exposure groups, whereas LPO remained unchanged in the PFOS exposure groups. Furthermore, a significant activation of caspase-3, -8, -9 activities was evident in both PFOS and PFOA exposure groups. Typical DNA fragmentation (DNA laddering) was further characterized by agarose gel electrophoresis. The overall results demonstrated that PFOS and PFOA are able to produce oxidative stress and induce apoptosis with involvement of caspases in primary cultured tilapia hepatocytes. (c) 2007 Elsevier B.V. All rights reserved.

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Water solubility enhancements of six phthalates (five aliphatic phthalates and one phenyl phthalate) by cetyltrimethylammonium bromide (CTAB) and beta-cyclodextrin (beta-CD) were studied at 25 degreesC. The solubilities of these plithalates are remarkably enhanced by CTAB solutions above the critical micelle concentration (cmc). Only marginal enhancement of phthalate solubility was observed in solutions containing CTAB below its cmc and beta-CD at low concentrations (less than 5 mM). The solubility enhancements of the plithalates are proportional to the added amount of CTAB and beta-CD. Partition coefficients of the plithalates between monomeric CTAB surfactant and water (K-MN) and between CTAB micelle and water K-MC) were estimated from the experimental data. The mechanisms of solubility enhancements by CTAB and beta-CD were discussed. A log-linear equation was proposed and evaluated for the solubilization by CTAB below cmc, while the previously proposed linear partitioning model was questioned. The structures of the complexes formed between plithalates and beta-CD were proposed, and the formation constants were estimated. The values of log K-MC, log K-MN, and log Kbeta-CD of the plithalates were found to correlate linearly with the log K-OW of plithalates, with the exception of the solid phenyl phthalate.

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有机锗化合物具有广谱抗癌活性和低毒副作用,有关它们的合成、生物活性及应用研究引起了医药界和化学界的兴趣。但由于未注重有机基团的相关性,忽略了分子整体对抗癌作用的影响,至今尚未出现临床应用的高效低毒的有机绪抗癌新药,分子结构与抗癌活性关系及抗癌作用机理仍不清楚。因此,继续合成新型且具有结构可比性的有机锗抗癌活性化合物,研究药物与生物大分子DNA的相互作用、揭示有机锗化合物的结构与抗癌作用关系,具有重要的理论意义和应用价值。为此,本论文就以下几个方面开展了研究工作。1、合成了4种有机锗二元杂环化合物一有机锗喳琳醋和有机锗蔡酚醋化合物。根据它们的光谱性质讨论了其结构特征,该类化合物具有与Ge-132类似的空间结构,即具有-Ge-O-Ge-O-聚合网络大环结构。由于保留了有机锗倍半氧化物的基本结构,同时引入了能够与DNA有强烈相互作用的蔡酚和喳琳基团,可能会产生协同效应,使新化合物具有较强的抗癌活性和较好的选择性。2、在保留有机锗倍半氧化物的基本结构的基础上,引入了本身具有抗癌活性和光谱学性质,并且能够与DNA有相互作用的葱、葱醒、菲、荀、荀酮等三环有机基团,合成了16种未见报道的有机锗三元杂环化合物。以葱环为代表的杂环化合物,例如氮杂葱醌及氮杂葱并吡唑类化合物,作为重要的抗癌活性化合物,引起了药学界的极大兴趣。我们合成的新化合物,既保留了有机锗倍半氧化物的基本结构,又引入了葱环类化合物,进而使新化合物具有较强的抗癌活性和选择识别性。3、选择了8个药物小分子,分别应用UV-Vis、热变性(Melting)、荧光光I新型有机锗化合物的合成、抗癌活性及其与DNA的相互作用研究谱变化、粘度测定等方法,研究它们与3种DNA,即小牛胸腺DNA(CT-DNA)和2种人I合成的寡聚核昔酸[22一merspoly(dA·d劝和22一merspoly(dG·dC)]的相互作用。发现与DNA作用后,这些化合物的紫外吸收光谱均发生减色效应和红移现象,它们能使3种DNA的热变性温度(几)升高,粘度增加,说明化合物是以插入方式与DNA结合的。应用荧光滴定方法,求得了新化合物与DNA的结合常数,场在1护一105M一l范围内,属中等强度结合。进一步研究发现它们是以1:2(小分子/碱基对)的计量比与DNA碱基结合的。4、2种有机锗菲醋化合物(G一1、G一2)与DNA结合后,紫外吸收光谱产生减色效应和兰移现象以及荧光淬灭,对DNA的粘度基本无影响,它们是以沟槽结合方式与DNA发生作用的。发现G-1和G-2不仅能够增加三链DNA-Polv(dA·ZdT油的稳定性,并且能够促进Poly(dA.ZdT)22的形成。这一结果说明,某些结构的有机锗化合物可能以这种作用机理发挥抗癌作用,同时可以作为潜在的三链DNA稳定剂。5、研究了部分新合成的有机锗化合物(GK-1,GK-2,GN-1,GN-2,EK-1,EK-2,D-1,D-2,G-,G-2)对PC一3M和K562癌细胞的作用。GK-1,GK-2能够显著抑"制PC一3M细胞的增值,而且对细胞形态也产生了严重影响,显示了明显的细胞毒作用。流式细胞实验结果表明EK类化合物对PC-3M细胞周期有很大影响,发现对细胞增值的抑制作用发生在S期,即细胞内DNA合成期,细胞实验的结果也进一步验证了药物与DNA相互作用的事实。GN-1,GN-2,EK-1,EK-2,D-1,D-2,G-和G一2对K562细胞表现了较强的抑制作用,尤其GN-1和GN-2,效果更为明显,说明分子内有机锗链和其它基团的协向作用增强了整体化合物的生物学作用。6、有机锗二元杂环化合物与DNA的结合常数和体外抗癌活性明显高于有机锗三元杂环化合物,结合强度和抗癌活性之间呈现线形相关性。有机链中甲基的存在不利于有机锗二元杂环化合物与DNA的作用,同时降低了抗癌活性,而同样甲基的存在有利于有机锗三元杂环化合物与DNA的相互作用和抗癌功能的发挥。

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本文主要研究了沈阳市主要绿化树种银杏(Ginkgo biloba)和油松(Pinus tabulaeformis)挥发性有机物(Volatile Organic Compounds,VOCs)排放的日变化、季节变化规律,同时采用开顶箱法研究了高浓度CO2(700 µmol•mol-1)、O3(80 nmol•mol-1)及复合作用下城市主要绿化树种银杏、蒙古栎(Quercus mongolica)、油松、华山松(Pinus armandii)VOCs排放规律,揭示了城市中树木VOCs排放的变化规律及其对高浓度CO2和O3的响应,为研究城市森林对全球变化的响应与反馈提供了科学依据。 本实验建立的热解吸与气相色谱联用方法,最小检测量为4×10-10 g,具有较高的灵敏度和精确度,可满足对树木VOCs分析的要求。研究发现,银杏和油松VOCs的释放具有显著的日变化和季节变化规律,二者夜间均不排放异戊二烯。α-蒎烯为油松释放VOCs的主要成份,同时发现油松排放的α-蒎烯,β-蒎烯,莰烯和柠檬烯之间具有显著相关关系,说明这几种化合物在遗传控制上有某种共同效应或者具有相同的代谢途径。不同树种排放的VOCs组成明显不同,银杏及蒙古栎主要排放异戊二烯,而油松和华山松主要排放单萜;蒙古栎VOCs释放量显著高于其他树种。市区树木VOCs排放速率显著高于郊区,沈阳市主要绿化树种银杏和油松VOCs的年排放量分别为12.16 t和14.48 t。大气CO2和O3浓度升高条件下,树木VOCs释放规律和排放组成,受植物种类和生长季的影响;单独提高大气CO2或O3浓度可显著影响树木VOCs的释放和组成,但是二者复合作用没有显著影响。

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东北土壤有机P库潜力巨大,通过调控磷酸酶活性来提高P的植物有效性是一条可行之路。本文以东北典型黑土和棕壤为供试土壤,从几种公认比较有效的有机化合物中筛选出具有实际可操作性浓度的磷酸酶(磷酸单酯酶,磷酸二酯酶和磷酸三酯酶)激活剂,并确定其最适浓度,研究其对土壤磷酸酶活性调节效果及其动力学特性,结果表明: 1、不同低浓度的还原型谷胱甘肽(GSH)、三磷酸腺苷(ATP)、辅酶I、L-半胱氨酸、生化腐殖酸、碘解磷定(PAM)中,160mg•kg-1 GSH在15天内对黑土三种磷酸酶有较好的激活效果,作为筛选出的激活剂。通过浓度调节试验,进一步确定480mg•kg-1还原型谷胱甘肽对黑土磷酸酶活性在30天内有很好的激活效果。 2、480mg•kg-1的GSH能够提高黑土磷酸单酯酶、二酯酶活性,对三酯酶没有激活效果,而对棕壤只激活三酯酶;同样的处理下,黑土单酯酶和三酯酶,棕壤的二酯酶和三酯酶Vmax值显著大于对照,激活剂处理的棕壤单酯酶及黑土的二酯酶Km值显著小于对照。 3、GSH作用下的黑土和棕壤有效P含量都与对照无显著差异;黑土和棕壤的微生物量P仅在短时间内略高于对照,但不显著;黑土可利用性P含量没有提高,甚至有时显著低于对照;而棕壤则在第5、7天显著高于对照,其它天与对照无显著差异。

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本文采用热解吸与气相色谱联用技术对沈阳市主要绿化树种银中杨(Populus alba × berolinensis)、垂柳(Salix babylonica)、榆树(Ulmus pumila)、皂角(Gleditsia japonica)、丁香(Syringa oblate)和水腊(Ligustrum obtusifolium)植物源挥发性有机物(Biogenic Volatile Organic Compounds,BVOCs)排放的日变化、季节变化规律进行了观测,并估算了这6种树的BVOCs排放通量;同时采用开顶箱法研究了高浓度CO2(700 µmol•mol-1)、O3(80 nmol•mol-1)及二者复合作用下蒙古栎(Quercus mongolica)和油松(Pinus tabulaeformis)BVOCs排放规律。研究结果如下所示: (1) 6种绿化树种BVOCs的释放具有显著的日变化和季节变化规律,且夜间几乎均不排放异戊二烯。 (2) 不同树种排放的BVOCs组成明显不同,银中杨、垂柳和蒙古栎以排放异戊二烯为主;油松主要释放α-蒎烯;榆树、皂角和丁香以释放柠檬烯为主;水腊在不同时段其BVOCs组成情况变化较大,主要释放异戊二烯、柠檬烯和α-蒎烯;其中银中杨和垂柳的BVOCs释放量明显高于其它树种。 (3) 在实测数据基础上,估算出沈阳市6种主要绿化树种银中杨、垂柳、榆树、皂角、丁香和水腊在自然条件下的BVOCs年排放量分别为104.86tC,168.66tC,3.56tC,1.27tC,4.07tC和1.33tC。 (4) 大气CO2和O3浓度升高条件下,树木BVOCs释放规律和排放物组成受植物种类和生长季的影响;单独提高大气CO2或O3浓度可显著影响树木BVOCs的释放,二者的复合作用对BVOCs释放的影响主要介于两者单独作用的结果之间。

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猪场废水COD浓度高、氨氮浓度高、悬浮物浓度高,已成为农村面源污染的主要来源,并严重威胁到农村饮用水安全。猪场废水氨氮浓度高、处理难度大,如何采用经济高效的方法,去除氨氮使其达到排放标准,一直是猪场废水处理中面临的重要难题。 厌氧氨氧化是近年受到国内外水处理研究者广泛关注的新型生物脱氮技术,具有不需要外加有机碳源、节省供氧量、降低能耗等优点。虽然国内外研究者对厌氧氨氧化过程的脱氮机理、厌氧氨氧化菌的生理生化特性等进行了多方面的研究,但已有的报道大多以模拟废水为研究对象,以猪场废水为研究对象的报道,在国内外文献中极少有报导。 本论文以猪场废水为主要研究对象,考察了猪场废水的亚硝化过程、厌氧氨氧化的启动过程,并对亚硝化和厌氧氨氧化联合用于猪场废水脱氮进行了探索。 1.论文首先研究了猪场废水的亚硝化过程,考察了废水水质和主要运行条件对亚硝化过程的影响。实验表明:(1)亚硝化阶段反应时间为8到10h时,出水中氨氮和亚硝酸盐浓度比可达到1:1~1:1.23,满足厌氧氨氧化反应对二者比例的要求;达到前述要求时,氨氮去除率达到58.3~65.6 %,亚硝化率在整个过程均保持在97 %以上,COD去除率在59.2~68.6 %;(2)曝气量(溶解氧)对亚硝化过程影响显著,随着曝气量增大,达到厌氧氨氧化要求的氨氮与亚硝酸盐氮浓度比例所需水力停留时间τ越短,pH出现明显下降的时间越短;(3)τ对应的pH在7.8~8.1之间,无需进行pH调节即可满足厌氧氨氧化反应对pH的要求;(4)氨氮和COD降解过程遵循一级反应动力学,氨氮和COD降解的速率常数分别为0.0656~0.0724 1/h和0.0491~0.0664 1/h。 2.在进行亚硝化过程研究的同时,以模拟废水为试验对象,进行厌氧氨氧化启动研究。以反硝化污泥和养殖厂储水池厌氧底泥的混合污泥作为接种污泥,历时大约100天,培育出具有厌氧氨氧化活性的污泥,氨氮和亚硝酸盐氮最高进水浓度分别为223.8 mg/L和171.4 mg/L,去除率最高分别达48%和41.5%,此时二者消耗比例为1.33:1。 3.在猪场废水的亚硝化研究完成和厌氧氨氧化过程初步启动成功后,在模拟废水中逐步加入猪场废水的亚硝化处理出水,逐步实现亚硝化和厌氧氨氧化的组合。亚硝化出水添加到厌氧反应器后,厌氧氨氧化反应仍可继续进行,且去除效率逐步提高。研究发现添加的亚硝化出水中携带的亚硝化细菌在厌氧氨氧化菌膜外层生长并累积,增加了厌氧氨氧化反应基质的传质阻力,妨碍了厌氧氨氧化效率的提高。 4.亚硝化-厌氧氨氧化实际工程应用探索中,生物接触氧化池可在有效去除废水中的有机物的同时实现亚硝化,出水中氨氮和亚硝酸盐比例平均为1.10,可满足后续厌氧氨氧化的要求;在适宜的进水浓度和温度下,ABR池出现了厌氧氨氧化启动的迹象;研究同时发现,水质的波动和气温的变化是工程中影响厌氧氨氧化菌活性的重要因素。 论文的主要创新点在于:(1)以猪场废水为研究对象,以实现厌氧氨氧化为目标,对亚硝化过程进行了比较详细的考察,获得了亚硝化出水满足厌氧氨氧化要求的工艺条件,通过对其COD和氨氮降解过程的考察,得出亚硝化阶段COD降解和氨氮去除的动力学模型;(2)对亚硝化-厌氧氨氧化处理猪场废水进行了探索,确立了影响其污染物去除率稳定的重要因素。 论文的上述研究成果,为厌氧氨氧化技术的实用性研究提供理论依据。 Piggery wastewater, which is characterized by high concentration of COD、ammonium and suspend substance, has become a most important source of non-point source pollution and also severely threats drinking water security in rural area. How to discharge piggery wastewater with the ammonium concentration meeting standard by economical and effective method? This is the most urgent problem in piggery wastewater treatment. As a new biological nitrogen removal technology, Anammox process has been paid more and more attention by researchers all over the world. Anammox has advantages of no need of organic carbon addition, low oxygen consumption and energy consumption. Plenty of investigations have been carried out to the mechanism, physiological and biochemical characteristic of bacteria about Anammox. Most of researches focused on synthetic wastewater, there is rare report about its application in piggery wastewater. In this paper,experimental studies were performed to investigate Sharon process in treatment of piggery wastewater,the start up process of Annammox using synthetic wastewater were studied, the feasibility of applying Sharon-Anammox process in the nitrogen removal of piggery wastewater was evaluated. 1. Sharon process of piggery wastewater was firstly investigated to analyze the effects of water quality and main running parameters, which meet the NH4+-N to NO2--N ratio requirement of successive Anammox. Results showed: (1)During Sharon Process,after 8~10 hours’ reaction the NH4+-N to NO2--N ratio in effluent reached 1:1.0~1:1.23, when the removal percentage of NH4+-N was 58.3~65.6 %, a semi-nitration rate of above 97 % was achieved during the process; meanwhile 59.2~68.6 % of the COD was also removed. (2)The aeration rate(oxygen) had obvious effect on the hydraulic retention time(τ) which met the NH4+-N to NO2--N ratio requirement of Anammox. As aeration rate increased, the hydraulic retention time(τ) was shortened. (3) The pH corresponding to τ was between 7.8 and 8.1, thus it needed no artificial adjustment. (4) The reduction of ammonia and COD followed the first-order reaction kinetics. The velocity constants of ammonia and COD were 0.0656~0.0724 1/h and 0.0491~0.0664 1/h, respectively. 2. The startup of Anammox process using the artificial wastewater was performed simultaneously with Sharon. The aim was to investigate the running parameters of Anammox and make foundation for the combination stage. By using the mixture of denitrifying sludge and anaerobic sludge in tank of the breeding factory, sludge of Anammox activity was cultivated in UASB after 100 days. The removal percentage of NH4+-N and NO2-N were up to 48% and 41.5%, respectively, when the NH4+-N and NO2-N influent concentration were 223.8 mg/L and 171.4 mg/L, respectively, the NH4+-N and NO2-N removal rate was 1.33:1. 3. After investigation of Sharon and startup of Anammox, effluent of Sharon process was added into the synthetic wastewater to combine Sharon and Anammox step by step. It took some time after the addition of Sharon effluent that Anammox reaction continued and the removal rate kept increasing. It indicated that nitrifying bacteria were carried by the Sharon effluent cumulated in the outer layer of Anammox. This enhanced transfer resistance of Anammox reaction and the increasing removal rate was restrained. 4. In the bio-contact oxidation pond of practical project, Sharon process were carried out successfully and organic compounds were removed effectively. An average NO2-N/ NH4+-N rate of 1:1.0 was achieved in the effluent, which met the requirement of successive Anammox. Under condition of suitable influent concentration and temperature, there was evidence that Anammox could start up in ABR. The variety of wastewater and temperature had great affects on Anammox activity in practical engineering. Innovation of this paper: (1) The Sharon process for treating piggery wastewater was discussed in details. Technological parameters that met requirement of Anammox were obtained. The dynamic models of COD and ammonium removal in the process were educed. (2) Sharon-Ananmmox for treatment of piggery wastewater was investigated, and the primary influencing factors was studied. This paper could be a theoretical consult for research of Anammox utility.

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本文介绍了从厌氧间歇膨胀光合反应器内的活性污泥中分离并鉴定的泥生绿菌(Chlorobium limicola Nadson)S1,它属严格厌氧光能自养型细菌,在有硫化物和少量碳酸氢盐存在下,有广泛利用有机物的能力,它的最适生长温度为28-30℃,最适生长PH为6.5-7.0,且含有氢化酶。因此,它能与甲烷发酵菌共存而共同作用,达到废水净化之目的。通过光照(2#反应器)和黑暗(1#反应器)对比实验,表明了在光照条件下即有泥生绿菌S1存在下,反应系统能更好地降低CODcr、BOD5 和提高CH4 含量,在四个负荷段的运行中,2#反应器在后三个负荷段的甲烷含量能稳定在91.6%而1#反应器为87%,2#反应器的二氧化碳含量为4.5%而1#反应器为8.8%,于28.35g/l.d的负荷下,2#反应器CODcr去除率达83.4%,BOD去除率达74.53%,分别较1#反应器高10.8%,6.4%。COD去除率提高了14%,BOD去除率提高了9.3%。本试验的试验条件为:白天自然光照,晚上电源光照,光照强度为1000-2500lux,通过连续动态运转,并以恒定的流速将废液注入反应器中,进水PH控制在6.5-7.2,反应器厌氧,恒温室温度控制在30±1℃。为使整个试验中同一水质条件下进行,进水采用化学合成培养基。This paper reports a Chlorobium Liwicola S1's isolation and identification. It is a strictly anaerobic and photosynthetic autotrophic bacterium. Along with sulfidedepondent CO2 assiwilaton,a few simple organic compounds can be photoassimilated. Acetate is most effectively used. Its best conditons of growth are 28-30℃,PH 6.5-7.0, and it contains hydrogenase. So it can live with methanefermentative bacteria in order to treat wastewater. At the same time, the treatment of wastwater using Chlorobium Limicola S1 with methane-fermontative bacteria under dark anaerobic and light anaerobic conditions is studied. In contrast with 1# reactor-darken, 2# reactor-illuminated can lossen wastewater's CODcr, BOD5 and on hance CH4 content better. In the test, 2# reactor's CH4 content is stable at 91.6%, but 1# reactor's is 87%. The CO2 content of 2# reactor is 4.5%, but 1# reactor's is 8.8%. When the load of teatment is 28.35g/l.d, the COD removal effficiency is 83.4% and the BOD removal efficiency is 74.53% in 2# reactor. They are separately 10.8%, 6.4% higher than 1# reactor's.

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经过细心的条件选择实现了无甲烷条件下甲烷氧化菌沼气甲基弯菌81Z(methylosinus methanica 81Z)利用C2化合物的生长,同时 发现二碳代谢中间产物甘氨酸的胞外积累及对生长的抑制作用。又在此基础上从81Z原种中富集得到一株菌81Z-A,兼性生长能力大 幅度提高,而且除乙酸外又能利用丙酮酸、苹果酸、柠檬酸、葡萄糖而生长。对细胞氧化各种有机底物时氧吸收的测定及酶分析结 果发现了在其它甲烷氧化细菌中未曾发现的异柠檬酸裂解酶和苹果酸酶的存在,表明81Z除了具有通常II型菌的碳代谢途径外,具 有特殊的补偿代谢途径——乙醛酸支路以及从乙酸生糖的回补途径。因此推证其兼性生长的能力是固有的,从而说明了甲烷氧化菌 的专一性概念没有普遍意义。说明了81Z还能在含有二碳的培养基中厌氧生长,包括细胞的分裂和增值行为。虽然这种厌氧生长还 很弱,但至少可以说明它不是严格好氧的,这对于传统的关于甲烷氧化菌的严格好氧的概念是一个冲击。81Z正常条件下是利用甲 烷而生长的,当供给它乙酸、乙醛酸和丝氨酸时能促进含C-C键有机物氧化的活性,而对甲烷单加氧酶和其它C2化合物的氧化有抑 制或阻遏作用,对碳同化的丝氨酸途径的关键酶羟基丙酮酸还原酶有阻抑作用。同时也证明了81Z的甲烷单加氧酶和甲醇氧化活性 可被甲烷、甲醇所诱导,而因甲酸而降低。The growth of Methylosinus methanica 81Z on C2-compounds without methane was realized by selecting suitable conditions. The intermediate product Gly from its C2 metabolism was found to accumulate out cells and inhibit its growth. 81Z-A, which was obtained from 81Z by richening, could grow on C2- compounds rapidly. It can even grow on pyruvate, malate, citrate and glucose. The results of measurements of oxygen consumption by cell suspensions in the presence of various organic compounds and the results of enzyme assays of detected activities of isocitrate lyaze and malic enzyme in cell extracts which were not found in other methantrophs showed that 81Z possesses not only the regular carbon metabalic pathways but also some peculiar anaplerotic pathways--the glyoxylate cycle and the gluconeogenic pathway from acetate. As a consequence of these studies, its ability of facultative growth is inherent. Therefore, the concept of obligate dependence on C2- compounds of methanotrophs is not of universal significance. The ability of 81Z's growth(including desintegration and proliferation behaviour) on C2-compounds anaerobically was also demonstrated. Despite of the weakness of this growth, at least it could be said that 81Z is not strictly aerobic. This is a strike to the traditonal concept about the strictly aerobic action of methanotrophs. Regularly, 81Z grows on methane. The presence of acetate, glyoxylate and serine could increaze its ability of oxidizing the organic coumpounds containing C-C ponds. In contrast, they could inhibit the activities of MMO and other C2-compounds oxidation, they also repressed the key enzyme hydroxypyruvate reductase of the serine-pathway for carbon assimilation. At the some time, it was testified that the activities of MMO and methanol oxidation were inducible by methane or methanol and were lower in the presence of formate.

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畜禽废水是农村水环境污染的主要来源之一,其处理的难点在于脱氮。传统生物脱氮法具有能耗高、需大量外加碳源等缺点,开发低成本、高效率的新型生物脱氮技术具有重要意义。 本研究将短程硝化反硝化和厌氧氨氧化两种脱氮新技术结合,让前者为后者创造去除可降解COD、降低总氮负荷、调整pH、调整氨氮和亚硝酸盐氮浓度比例等进水条件,而后者可在无需外加碳源的条件下进一步脱氮,二者结合可成为高氨氮、低C/N废水脱氮的新途径。 试验以低碳氮比猪场废水为研究对象,首先进行了短程硝化反硝化预处理研究,同时启动并运行调控厌氧氨氧化反应器,最后以经过短程硝化反硝化预处理的猪场废水为进水,进行厌氧氨氧化脱氮考察。实验表明:(1)短程硝化反硝化作为厌氧氨氧化的预处理工序是可行的。猪场废水通过短程硝化反硝化,可以达到基本去除可生化COD、部分脱氮、控制出水氨氮和亚硝酸盐氮浓度之比在1︰1左右、pH在7.5~8.0的目的, COD和总氮平均去除率分别为64.3%、49.1%,出水可达到厌氧氨氧化反应的进水要求。(2)采用模拟废水启动厌氧氨氧化反应器,经过5个月左右的运行调控,反应器启动成功并稳定运行,最高总氮去除率为87.1%,总氮容积去除率最高达到0.14kg/m3.d;整个稳定阶段,氨氮、亚硝酸盐氮、硝酸盐氮的变化量之比为1︰1.21︰0.33。(3)经过短程硝化反硝化预处理的猪场废水厌氧氨氧化脱氮效果稳定,氨氮、亚硝酸盐氮、总氮、COD的平均去除率分别为93.0%、99.4%、84.6%、18.1%,处理效果与模拟废水处理系统相比无明显变化。(4)经过短程硝化反硝化预处理后,猪场废水中残留有机物成分在厌氧氨氧化反应过程中无显著变化,主要为酯类和烷烃类物质;残留有机物对厌氧氨氧化效果无明显影响。(5)采用PCR技术进行特殊功能菌种检测,结果表明模拟废水处理系统和猪场废水处理系统的菌群中均含有厌氧氨氧化菌和好氧硝化菌;通过blast比对,厌氧氨氧化菌扩增序列与未培养的Planctomycetales菌和Candidatus Brocadia fulgida菌16S rRNA部分序列相似性分别为95%、90%。(6)MPN法菌种计数结果显示,模拟废水处理系统和猪场废水处理系统的菌群中均含有硝化细菌、亚硝化细菌和少量反硝化菌,实验条件下的微生物系统是一个厌氧氨氧化菌与好氧硝化菌、反硝化菌共存的系统。 Poultry wastewater is one of the main source of water pollution in rural areas,and nitrogen removal is the most difficult part in treating poultry wastewater. There are some disadvantages in traditional nitrogen removal, such as high energy consumption and more additional organic carbon. It is important to develop ecolomical and efficient technologyies. Shortcut nitricfication/denitrification, as a pretreatment process, was combined with Anammox in this research, so that part of total nitrogen and most degradable COD could be removed by the former, and further nitrogen removal could be implemented by the latter. The combination of the two technologies was a new approach to treat wastewater with high ammonium and low C/N. Piggery wastewater with low C/N was treated in lab-scale experiment. Firstly, shortcut nitrification/denitrification was investigated, and Anammox reactor was started up successfully at the same time. Then piggery wastewater after pretreatment was treated by Anammox. The results showed :(1) It was feasible to take nitrification/denitrification as the pretreatment process of Anammox. By using this process, part of total nitrogen and COD were removed, the ratio of ammonium and nitrite reached around 1︰1 and the pH was about 7.8, which were favorable for Anammox. The average removal percentage of COD and total nitrogen were about 64.3% and 49.1%, respectively. (2) Simulated wastewater was used to start up Anammox reactor. The reactor was started up successfully within 5 months and stable performance was achieved. The highest nitrogen removal reached 87.1% and the biggest volumetric total nitrogen removal rate reached 0.14kg/m3.d. The average ratio of ammonium, nitrite and nitrate was 1:1.21:0.33. (3)Taking the effluent of shortcut nitrification/denitrification as the influent, the nitrogen removal efficiency of Anammox was stable, and the the average removal percentage of ammonium, nitrite, total nitrogen and COD were 93.0%, 99.4% , 84.6% and 18.1%, respectively, which had little difference with that by using simulated wastewater..(4) After pretreatment, the residual organic carbon in piggery wastewater showed no obvious change during the Anammox process, and the main organic compounds were saturated hydrocarbon and ester, which had no obvious negative effect on Anammox process.(5) By PCR technology, the existence of Anammox bacteria was confirmed and the aerobic nitrifying bacteria was found to coexist as well. The result of blast showed that the identities of Anammox bacterium to part of 16S rRNA sequence of uncultured Planctomycetales bacterium and Candidatus Brocadia fulgida bacterium were 95% and 90%, respectively.(6)By MPN method, nitrite oxidizer, ammonium oxidizer and denitrification bacteria were detected in both simulated and piggery wastewater treatment system of Anammox, and the microorganism system was composed of Anammox bacteria,aerobic bacteria and denitrification bacteria together.

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This review surveys the recent progress in the adsorbed stationary phases for capillary electrochromatography (CEC). Adsorption-based methods for preparation of stationary phase are novel approaches in CEC, which allow rapid and facile preparing stationary phases with desirable selectivity onto an open-tubular fused-silica capillary, a baresilica or ion-exchange packed column or a monolithic silica or polymer column. A variety of adsorbing agents have been developed as adsorbed stationary phases, including ionic long-chain surfactant, protein, peptide, amino acid, charged cyclodextrin (CD), basic compound, aliphatic ionene, and ion-exchange latex particle. The adsorbed stationary phases have been applied to separation of neutral, basic and acidic organic compounds, inorganic anions and enantiomers. They have also been applied to on-line sample concentration, fast separation and study of the competitive binding of enantiomers with protein.

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A variety of short-lived, reactive chemical species (i.e. free radicals and excited state species) are known to be photochemically produced in natural waters. Some of these transients may strongly affect chemical and biological processes, and they have been implicated in the degradation of organic pollutants and natural organic compounds in aqueous environments. Previous studies demonstrated that the highly reactive hydroxyl radical (OH) is photochemically formed in seawater. However, the quantitative importance of this key species in the sea has not been previously studied because of past analytical limitations. By using a highly sensitive probe based on α-H atom abstraction from methanol, we were able to measure production rates and steady-state concentrations of photochemically produced OH radicals in coastal and open ocean seawater and freshwaters. The validity of the method was tested by intercalibrating with an independent, OH-specific reaction, hydroxylation of benzoic acid, and also by competition kinetics experiments. Our OH production rates and steady-state concentrations for freshwaters are in excellent agreement with those measured by previous investigators for similar waters. In contrast, for seawater, the values we measured are 1–3 orders of magnitude higher than previously predicted by models, indicating that there is a major unknown photochemical OH source (s) in seawater.