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1.
In this study the influence of the low-intensity ultrasound treatment on excess sludge has been observed.The oxygen uptake rate(OUR),soluble chemical oxygen demand(SCOD),soluble total nitrogen(TN) and soluble total phosphorus(TP) were examined for three power levels of 0.03 W/mL, 0.05 W/mL and 0.1 W/mL as well as two time series of 0~5 min and 0~30 min.It showed that there were two stages of ultrasonic treatment: the first stage took place within the flocs in four minutes,in which SCOD,TN,TP were dissolved from flocs.In the second stage,the microbial activities have been strengthened,as well as OUR,TN,TP have increased greatly.  相似文献   

2.
表面活性剂SDS对草鱼急性毒性效应的研究   总被引:3,自引:0,他引:3  
为了研究阴离子表面活性剂对鱼类的急性毒性效应,设计了不同浓度的十二烷基硫酸钠(SDS)溶液对草鱼进行暴露实验并测定其体内各组织SOD活性。急性毒性测试表明,SDS对草鱼的48h、96h LC50分别为11.8 mg/L和5.2 mg/L。低浓度的SDS(小于0.2 mg/L)暴露对草鱼的超氧化物歧化酶(SOD)活性有极显著诱导作用,但随着SDS浓度升高和暴露时间延长,草鱼各组织SOD活性均呈明显的下降趋势,提示SDS暴露所引起的酶活性变化与暴露浓度和暴露时间有一定的相关性。这些结果显示,阴离子表面活性剂SD  相似文献   

3.
Two enhanced biological phosphorus removal (EBPR) sludges were used to investigate the effect of nitrite on anaerobic metabolism of phosphate accumulating organisms (PAOs). It is found that tolerance of PAOs to nitrite in two sludges were different. In the sludge with enriched PAOs cultures treating synthetic wastewater, when nitrite is above 10 mg/L, it inhibits VFA-uptake of PAOs, leading to decrease of PHA synthesis and increase of phosphate release. In the sludge with nitrogen and phosphorus removal by shortcut nitrification treating real domestic wastewater, anaerobic metabolism of PAOs is not inhibited even when nitrite is 30 mg/L; however, the presence of nitrite in anaerobic period causes denitrifying bacteria compete for limited carbon sources with PAOs, resulting in decrease of PHA synthesis and phosphate release. For the enriched PAOs cultures, the ratio of P/VFA obviously increases when nitrite is added in the reactor, indicating increased energy requirement for PAOs to take up VFA. The quantification results for PAOs in two sludges using fluorescence in-situ hybridization (FISH) show that the PAOs level is 55% in the enriched PAOs cultures, and 7.6% in the sludge with nitrogen and phosphorus removal by shortcut nitrification.  相似文献   

4.
谢磊 《中国农学通报》2010,26(17):367-369
通过城市污水处理厂的活性污泥培养出好氧颗粒污泥并处理高浓度猪场废水,对pH值、溶解氧浓度、进水浓度等主要操作条件进行了单因素试验。实验结果表明,颗粒污泥具有良好的生物活性。在进水氨氮浓度较高(>800mg/L)、pH为8左右、溶解氧浓度在2.0mg/L的条件下,稳定运行数天后,氨氮和COD的去除率均可达到80%以上。  相似文献   

5.
外源物质处理对番茄抗冷性的影响   总被引:1,自引:0,他引:1  
本试验以番茄为材料,利用不同浓度的外源生长调节物质处理番茄幼苗期幼苗,测定各项生理生化指标数值。结果表明,经过脱落酸、水杨酸、多效唑、茉莉酸外源诱导的番茄幼苗抗冷性明显高于对照。随着诱导浓度的增大,抗寒性逐渐增强,相对电导率逐渐降低,当脱落酸浓度为200ug/g和水杨酸浓度为400mg/L时,相对电导率降低近一倍;脯氨酸和可溶蛋白都随着处理浓度的增大显著提高,过氧化物酶的活性随处理浓度的增大而逐渐减少。在不同浓度的处理下, ABA浓度增长量同比增长最大为浓度100 ug/g和150 ug/g;水杨酸浓度增长量同比增长最大为浓度300 mg/L;多效唑浓度增长量同比增长最大为60 mg/L;茉莉酸浓度增长量同比增长最大为200 mg/L。外源生长调节物质处理使植株的抗冷性提高,但在品种上有差异,对抗冷性强的品种效果明显。  相似文献   

6.
Ecological Stabilization for Sewage Sludge   总被引:2,自引:0,他引:2  
Pilot scale sewage sludge ecological stabilization system was conducted for sludge dewatering,mineralization and stabilization.The study was performed from 2005 to 2008 on a bed with a total area of 80 m 2.Influent total solid,volatile solid and water content were averaged 22.34 g/L,7.76 g/L and 97%.Sludge loading rate was averaged 0.691 kg(TS)/m 2·d.The first two years were sludge loading period and the other two years were natural stabilization period.The percolate COD removals ranged from 60%~80% in the first year,and from 40%~50% in the second year,with 100~200 mg/L of effluent COD concentration.During the first two years,the percolate did not filtrate downwards evenly.Part of percolate filtrated downwards along stems,roots and cracks existing in dried sludge which had lower flow resistance.During the natural stabilization periods,sludge water contents decreased to 34.3% and 30.5%,and organic matter contents decreased to 16.8% and 10.24% in the third and forth years,individually.Total nitrogen and total phosphorus contents of stabilized sludge were averaged to 0.98% and 0.27%.It was found that plant biomass and nutrient components in the system were higher than that of native ones.  相似文献   

7.
铜是瘤胃微生物活动不可缺少的元素,为研究日粮添加无机铜对瘤胃微生物发酵的影响,本试验用人工瘤胃模拟装置发酵72h研究添加不同水平铜(0、6、12、18、24和30mg/kg干物质(DM))对体外瘤胃微生物发酵挥发性脂肪酸(VFA)产生量、瘤胃液氨浓度和微生物氮产量的影响。结果表明,添加铜可使发酵液不同时间点氨浓度和总氨产量、有机物发酵率显著提高(p<0.05),而对发酵罐中总微生物氮产量没有影响(p>0.05);与不添加的对照组相比添加铜可使发酵液的总VFA、乙酸、丙酸、丁酸浓度明显增加(p<0.05),但乙酸、丙酸、丁酸摩尔比例没有差异(p>0.05)。添加铜明显促进瘤胃有机物的发酵,增加瘤胃VFA产生量。  相似文献   

8.
闽江流域地表水质季节性变化特征研究   总被引:4,自引:0,他引:4  
依据2007-2008年闽江流域11个断面不同季节地表水有机污染指标的跟踪监测数据,对闽江流域地表水质的季节性变化特征进行了初步研究。结果表明,地表水体中有机污染指标存在明显的季节性差异。COD浓度随季节变化以7月和11月较高,年内变化范围5.0 mg.L-1~28.0mg.L-1;NH+4-N浓度则1月、 3月较高,年内变化范围0.18 mg.L-1~2.97mg.L-1;TN和NO-2-N浓度均以11月较高,年内变化范围分别为0.81 mg.L-1~3.23mg.L-1和0.01 mg.L-1~0.15mg.L-1;TP浓度1月、11月较高。但COD、NH+4-N、NO-2-N、浓度均以9月较低。而且,COD、NH+4-N、NO-3-N 与TN;NH+4-N与TP之间存在显著正相关。相对而言,闽江流域水质随季节变化以秋季较好,冬、春季较差。  相似文献   

9.
In order to explore the effectiveness and feasibility of urban green space on regulating urban rainfall-runoff pollution, the simulated test of soil column was adopted to study the effects of vegetation cover, runoff pollution concentration, soil depth and groundwater, and hydraulic loading rate and residence time on reducing the pollutants by green space. The results indicate that green space has a good and stable ability to reduce three stormwater runoff pollution concentrations, which COD are 68, 137 and 550 mg/L, TN are 3.01, 7.51 and 30.06 mg/L, TP are 0.29, 0.69 and 2.73 mg/L, and NH+4 are 0.44, 1.61 and 2.19 mg/L respectively, with 3.5, 3.0 and 2.5 cm/h hydraulic loading rate respectively and continuous inflow 1h. The pollution reduction rates of COD, TN, TP and NH+4 by green space reach to 41.52%, 78.96% and 84.68%, 50.21%, 70.23% and 60.91%, 73.18%, 95.88% and 94.99%, and 62.72%, 55.16% and 69.98% respectively. Restricted by the soil reaeration capacity and hydraulic retention time, the effect of vegetation cover on pollution reduction rates of COD and TN is not significant. With the rainfall-runoff pollution concentration increased, the pollutant reduction rate of green space shows a gradually increasing trend. The reduction of green space on the stormwater runoff pollution mainly occurs in the soil depth of 35~65 cm. The reduction rate of each pollutant for the low, medium and high pollution concentration level decrease with the hydraulic loading rate increased.  相似文献   

10.
为探讨HA、金属Cu2+以及活性污泥三者间的相互作用关系,研究了在HA存在下,不同吸附时间、pH值、Cu2+质量浓度以及温度对活性污泥吸附Cu2+的影响,并从热力学、吸附前后活性污泥性状以及红外光谱等角度分析了活性污泥吸附Cu2+机理。结果表明,当活性污泥为2 g/L、HA质量浓度为50 mg/L、pH=6,Cu2+质量浓度为50 mg/L时,经过90 min达到吸附平衡,Cu2+吸附量为45.98 mg/L,吸附率达到91.96%。研究发现,HA可以削弱Cu2+对活性污泥的毒性,活性污泥吸附Cu2+主要依靠氢键力和偶极间力,而多糖类、脂类C-O及苯环C-H等官能团在吸附过程中发挥着主要作用。  相似文献   

11.
In previous studies in vitro-selection of proline overaccumulating lines of winter wheat (Triticum sativum L. cv. Jo 3063) with increased frost tolerance was reported. These traits were found to be genetically stable. In the present study the improvement of frost tolerance (winter hardiness) under field conditions is confirmed for F7 progenies of the mutants. Moreover, the mutants accumulated higher levels of glucose and fructose, soluble protein and abscisic acid (ABA) in addition to proline than the wild type under cold hardening conditions in a growth chamber as well as under cold hardening field conditions. ABA and proline levels peaked when the temperature decreased, whereas carbohydrate levels increased more slowly at decreasing temperature. Soluble protein levels also increased during cold hardening, but in addition showed sharp declines during frost periods. Increased carbohydrate levels of the mutants were associated with lower osmotic potential values. The differences in carbohydrate, protein and ABA levels between the mutants and the wild type are probably due to pleiotropic effects of the mutation.  相似文献   

12.
Wastewater from a slaughtering house was treated by an anaerobic baffle reactor (ABR). The effects of variable loads on the operating performance of the ABR were studied. The results show that the ABR was very stable with respect to shock loading due to its special structure. The change in COD removal efficiency was less than 5% when the influent COD concentration was kept between 2 500~3 000 mg/L and the HRT decreased from 27.5h to15h. When HRT was kept for 20h and the influent COD concentration increased from 2 500 mg/L to 4 800 mg/L, COD removal efficiency only decreased by 69% the second day after the load change.  相似文献   

13.
[目的]为研究最适合快菜的微生物富硒菌肥的喷施浓度及最适施肥时间,为富硒快菜在实际生产的推广和应用提供理论指导,[方法]本试验以“京研快菜”作为试验材料,在田间进行叶面喷施5种不同浓度微生物富硒菌肥(包括空白对照)的裂区实验。[结果]试验结果表明,叶面喷施微生物富硒菌肥能够明显增加快菜中的单株重量、主根长度、叶片长度,硒含量、可溶性蛋白质含量与维生素C含量。其中浓度为40 mg/L的微生物富硒菌肥能有效提高作物的硒含量;浓度为13.3 mg/L的微生物富硒菌肥能够有效提高单株重量、叶长、可溶性蛋白质含量与维生素C含量;浓度为10 mg/L的微生物富硒菌肥能够有效提高作物的主根长和可溶性蛋白质含量。[结论]综合来说,以喷施低浓度硒肥(10 mg/L和13.3 mg/L)后物质含量提升最高,同时最佳施肥时期为在采收前一周。  相似文献   

14.
为比较人工湿地污水处理系统中芦苇(Phragmites communis)和茭白(Zizania aquatica)的生理特性及抗逆性,本研究选择山西省襄汾县污水处理厂人工湿地系统,采集湿地和对照土壤中的芦苇和茭白的叶和根样本,测定其生理指标、抗逆性指标。同时检测湿地土壤基本理化性质。结果表明,湿地芦苇和茭白叶中叶绿素、可溶性蛋白和MDA的含量比对照组增加(分别由23.56 mg/g、15.89 mg/g;0.98 g/L、1.43 g/L;0.11 nmol/mg protein、0.29 nmol/mg protein增加至44.27mg/g、33.17 mg/g;2.10 g/L、2.61 g/L;0.7 nmol/mg protein、1.01 nmol/mg protein),但无显著性差异;芦苇和茭白叶中超氧化物歧化酶(SOD)活性、根中可溶性蛋白含量和根中细胞色素氧化酶P450(CYP450)活性与对照组相比显著性增加(分别由0.32 U/mg protein、32.68 U/mg protein;0.09 g/L、0.38 g/L;176.98 U/mg protein、39.96 U/mg protein增加至54.73 U/mg protein、43.79 U/mg protein;0.11 g/L、0.45 g/L;361.46 U/mg protein、50.79 U/mg protein)。与茭白相比,湿地芦苇中MDA含量较低、SOD活性高、CYP450活性增加。结果说明,芦苇和茭白均是良好的人工湿地修复植物,SOD、CYP450保护酶的共同作用及可溶性蛋白和叶绿素增加是植物对逆境的一种适应反应,且芦苇的抗胁迫能力相对优于茭白。芦苇根可溶性蛋白和茭白根SOD分别与根中磷或钾呈显著正相关,说明植物生化指标与土壤养分密切相关。  相似文献   

15.
干旱是影响西北地区玉米生长发育的主要因素之一,5-氨基乙酰丙酸(5-ALA)是一种潜在的生理活性物质,具有增强植物抗逆性的作用。为了探明干旱胁迫下5-ALA对玉米种子萌发和幼苗生长的缓解效应,同时筛选出缓解的最佳浓度,以玉米品种“郑单958”为材料,以蒸馏水为对照,研究20% PEG 6000模拟干旱胁迫下不同浓度5-ALA(0、5、10、15、20、25、30mg/L)对玉米种子萌发及幼苗生长的影响。结果表明,与对照相比,干旱胁迫下玉米种子的萌发和幼苗生长受到明显抑制,幼苗的渗透调节物质含量减少,抗氧化酶活性降低,丙二醛(MDA)含量增加,质膜透性增大。与0mg/L 5-ALA处理相比,一定浓度(25mg/L)的5-ALA能明显缓解干旱胁迫对玉米幼苗造成的伤害,玉米幼苗的主根长、芽长、根鲜重、芽鲜重、根干重和芽干重显著增加,种子发芽势和发芽率显著提高了76.92%和65.52%,脯氨酸、可溶性糖和可溶性蛋白含量分别上升了136.82%、81.36%和121.26%,超氧化物歧化酶、过氧化物酶和过氧化氢酶活性分别增加了200.58%、182.10%和536.56%。MDA含量和细胞质膜透性则分别下降64.54%和68.21%。5-ALA的缓解作用具有明显的剂量效应,其中以浓度25mg/L处理效果最好。  相似文献   

16.
以盐生植物盐爪爪种子为材料,比较不同浓度中性盐(NaCl)和碱性盐(Na2 CO3)胁迫对其种子萌发过程中生理指标的影响.结果表明,0~100 mmol/L NaC1处理后盐爪爪萌发种子中丙二醛含量无显著变化,而0~100 mmol/L Na2CO3处理后丙二醛含量显著升高;NaCl处理的萌发种子中可溶性糖变化较平稳且呈现上升趋势,Na2CO3处理的种子可溶性糖先升高后降低;0~ 100 mmol/L NaCl处理后盐爪爪萌发种子中脯氨酸含量基本保持不变,而0~100 mmol/L Na2CO3处理后脯氨酸含量急剧上升;NaCl处理后可溶性蛋白上升幅度大于Na2CO3处理后上升幅度,二者的差异达到极显著水平.研究发现,盐爪爪种子萌发对于低浓度中性盐(NaCl)胁迫具有较强的耐性和抗性,而在碱性盐(Na2CO3)的胁迫下其萌芽受到一定的抑制.  相似文献   

17.
为了探明稀土元素镧对脐橙叶片渗透调节的影响,本研究以2年生‘纽荷尔’脐橙为试验材料,采用0 mg/L(CK)、50 mg/L、150 mg/L和300 mg/L硝酸镧溶液喷施脐橙叶片,分别于喷施后0、2、4、8、12、24 h采集植株中上部当年生嫩叶,测定渗透物质可溶性糖、可溶性蛋白与游离脯氨酸含量。结果表明:不同生长时间,脐橙叶片(CK)可溶性蛋白含量积累先升高后降低,可溶性糖和游离脯氨酸含量积累持续降低;喷施不同浓度硝酸镧溶液后,脐橙叶片游离脯氨酸含量的积累趋势发生改变。当喷施50 mg/L和150 mg/L的硝酸镧时,可同时促进脐橙叶片中可溶性糖、可溶性蛋白与游离脯氨酸含量的积累;当浓度提高到300 mg/L时,叶片可溶性糖和游离脯氨酸含量的积累明显高于其他处理,但可溶性蛋白含量的积累明显受到抑制。由此可见,喷施硝酸镧后,脐橙叶片通过主动积累可溶性糖、可溶性蛋白与游离脯氨酸来适应和调节细胞渗透胁迫;由于渗透物质种类的不同,导致促进其含量积累的适宜浓度存在差异,其中适宜可溶性蛋白含量积累的浓度为≤150 mg/L;适宜可溶性糖和游离脯氨酸含量积累的浓度为≥300 mg/L。研究结果可为进一步研究稀土元素对脐橙渗透物质影响的作用机理及生理代谢的调控提供参考依据。  相似文献   

18.
瓜尔豆发育过程中碳水化合物含量的变化   总被引:1,自引:0,他引:1  
胡春梅  王秀峰  季俊杰  朱月林 《作物学报》2007,33(11):1869-1873
研究了瓜尔豆生长发育过程中叶片、种荚及籽粒中蔗糖合成酶(SS)和蔗糖磷酸合成酶(SPS)活性的变化、糖类物质的组成及其含量的动态变化,以揭示可溶性糖的合成对瓜尔豆胚乳中半乳甘露聚糖和淀粉积累的影响。结果表明,进入开花期(播种后45 d)后,叶片、种荚和籽粒中SS和SPS活性均呈降低趋势。籽粒中的SS和SPS活性呈正相关,且显著高于叶片和种荚中相应酶活性。叶片中葡萄糖(Glc)含量高于蔗糖(Suc)。种荚中可溶性糖含量与Suc含量均呈单峰曲线,在籽粒直径5 mm时达峰值,两者呈正相关。Suc是种荚中暂存含量最多的可溶性糖,但其含量与SS和SPS活性无显著相关性,它主要来自叶片。种荚中Suc含量与籽粒碳水化合物总量(可溶性糖+多糖)呈负相关,它是籽粒碳水化合物合成的重要物质来源,还与籽粒库的建成有关。随种子发育,籽粒可溶性糖含量呈逐步下降趋势。籽粒发育前期,叶片同化物以Suc的形式运输并大量积累在种荚中,当籽粒直径达5 mm后迅速由种荚卸载至籽粒。但卸载期籽粒Suc含量较低,且显著低于种荚,说明籽粒Suc迅速转化为其他可溶性糖,并进一步用于多糖合成。籽粒直径为4 mm至5 mm时是种荚由“源”到“库”转换的临界期,这时籽粒中淀粉积累较迅速,半乳甘露聚糖在籽粒直径达5 mm后进入迅速积累期。  相似文献   

19.
海水水质直接影响养殖业发展及海洋产品品质,受到越来越越多关注。为了解扇贝养殖区域海水水质状况及对扇贝品质的影响,采用分期取样的方法,在莱州湾某扇贝养殖区采集表层海水样品,以非养殖区为对照,分析其pH、营养盐、COD、Cu及Zn含量。同时,采集扇贝幼体、成体,分析Cu、Zn在闭壳肌(贝柱)中蓄积。结果表明,研究区域海水中无机氮含量较高,接近0.30 mg/L,不同时间其含量和组成差异显著,10月海水中无机氮以硝态氮为主,含量极显著高于以氨态氮为主的6月(P<0.01)。不同时间,不同采样点海水中无机磷含量均小于0.02 mg/L,差异不显著。COD、Cu及Zn含量均为6月显著高于10月(P<0.05),未超出二类海水水质标准值。COD、Cu及Zn三者间呈极显著正相关(P<0.01),表明它们可能来自同一污染源。扇贝对Cu、Zn的富集能力较强,对Zn富集能力大于Cu。尽管扇贝闭壳肌中Cu、Zn含量在相关标准值之内,但Cu、Zn富集程度分别达到了1.06、0.821,所以,扇贝养殖过程中Cu、Zn等重金属在体内蓄积应引起更多关注。  相似文献   

20.
粘土矿物对污水中可溶态N、P的吸附研究   总被引:1,自引:0,他引:1  
蒋先军 《中国农学通报》2010,26(13):349-353
在室内模拟条件下,研究了活性炭、高岭土、人造沸石、蛭石、珍珠岩、蒙脱石共六种粘土矿物及其用量对污水中可溶态N、P的吸附效果。它们对铵态氮的沉降率分别是:1%,4%,78%,11%,2%,26%;对硝态氮的沉降率分别是:32%,6%,4.5%,3.6%,0.8%,56%;对可溶态P的沉降率分别是:35%,-22%,9%,11.7%,3.6%,16.8%。结果表明,人造沸石是沉降铵态氮的最佳粘土矿物,而活性炭既是硝态氮的最佳粘土矿物,同时也是可溶态P的最佳粘土矿物。综合去除率和经济效益,吸附铵态氮,最佳的沸石浓度1.5g/L,单位吸附量11.8mg/g,吸附率59%;吸附硝态氮,最佳的活性炭浓度为12g/L,单位吸附量0.108mg/g,吸附率51%;吸附磷酸根,最佳的活性炭浓度为2.0g/L,单位吸附量0.26mg/g,吸附率26%。  相似文献   

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