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Epigallocatechin gallate (EGCG) of green tea and the nutraceutical CystiCran®-40 (containing 40% proanthocyanidins) of the cranberry plant have been associated with antiviral activity. The purpose of this work was to determine the mechanism of antiviral synergy between each compound. Coliphage T4II (phage T4) and the rotavirus strain SA-11(RTV) were used as model virus systems. Individual and combined flavonoids structural and molecular weight analyses were performed by NMR and HPCL/MS, respectively. A suboptimal concentration of EGCG or C-40 alone or in combination reduced phage infectivity by ≤10%. Similarly, EGCG (30 µg/ml) and C-40 (25 µg/ml), respectively, reduced RTV titers by 3 and 13%. However, RTV titers were reduced by 32% (p < .05) with both flavonoids used in combination. RTV was not recognized in host cells by electron microscopy 24-h post-inoculation. NMR and HPLC/MS findings revealed significant structural and potential changes in molecular weight of the flavonoids in complex.  相似文献   

3.
Removal of 2-methylisoborneol (MIB) in drinking water by ozone, powdered activated carbon (PAC), potassium permanganate and potassium ferrate was investigated. The adsorption kinetics of MIB by both wood-based and coat-based PACs show that main removal of MIB occurs within contact time of 1 h. Compared with the wood-based PAC, the coat-based PAC evidently improved the removal efficiency of MIB. The removal percentage of trace MIB at any given time for a particular carbon dosage was irrelative to the initial concentration of MIB. A series of experiments were performed to determine the effect of pH on the ozonation of MIB. The results show that pH has a significant effect on the ozonation of MIB. It is conclusive that potassium permanganate and potassium ferrate are ineffective in removing the MIB in drinking water.  相似文献   

4.
改性活性炭对水中PFOS的吸附去除研究   总被引:5,自引:4,他引:1  
童锡臻  石宝友  解岳  王东升 《环境科学》2012,33(9):3132-3138
分别用FeCl3及中功率微波对煤质和椰壳2种粉末活性炭进行改性.序批式实验研究了活性炭改性前后对全氟辛烷磺酸(PFOS)的吸附特性.结合活性炭改性前后表面化学官能团和孔结构的变化特征,探讨了不同改性方式对PFOS吸附去除的影响效应以及天然有机物中的主要组成成分腐殖酸对PFOS在原炭及改性炭上的竞争吸附效应.结果表明,Fe3+及中功率微波处理对煤质炭和椰壳炭的孔结构和表面性质都有影响,但变化趋势不同.椰壳活性炭经Fe3+及中功率微波改性后对PFOS的吸附量明显提高,而煤质活性炭经改性后对PFOS的吸附量出现下降.改性椰壳活性炭与原炭吸附PFOS达到吸附平衡的时间基本相同,均为6 h左右.在腐殖酸存在下,改性椰壳炭对PFOS的吸附量因竞争吸附而有所下降,但改性炭的吸附量仍明显高于原炭.  相似文献   

5.
采用3种混凝剂(三氯化铁(FeCl3)、高效聚合氯化铝(HPAC)、聚合氯化铝(PAC))对滦河水进行强化混凝中试对比试验研究。试验结果表明:在相同的混凝剂成本条件下,采用常规处理工艺时,PAC和HPAC对浊度的去除效果都很好,HPAC对CODMn和UV254的去除效果最好。在滦河水正常水质期,不同的投加量均能使出水浊度和CODMn达到《城市供水水质标准》(CJ/T206-2005)的要求。  相似文献   

6.
Powdered activated carbon (PAC) adsorption of two fishy odorants, trans,trans-2,4-heptadienal (HDE) and trans,trans-2,4-decadienal (DDE), was investigated. Both the pseudo first-order and the pseudo second-order kinetic models well described the kinetics curves, and DDE was more readily removed by PAC. In isotherm tests, both Freundlich and Modified Freundlich isotherms fitted the experimental data well. PAC exhibited a higher adsorption capacity for DDE than for HDE, which could be ascribed to the difference in their hydrophobicity. The calculated thermodynamic parameters (ΔG0, ΔH0, and ΔS0) indicated an exothermic and spontaneous adsorption process. PAC dosage, pH, and natural organic matter (NOM) presence were found to influence the adsorption process. With increasing PAC dosage, the pseudo first-order and pseudo second-order rate constants both increased. The value of pH had little influence on HDE or DDE molecules but altered the surface charge of PAC, and the maximum adsorption capacity occurred at pH 9. The presence of NOM, especially the fraction with molecular weight less than 1 k Dalton, hindered the adsorption. The study showed that preloaded NOM impaired the adsorption capacity of HDE or DDE more severely than simultaneously fed NOM did.  相似文献   

7.
为增强饮用原水中藻类的混凝去除效果,以铜绿微囊藻和水华鱼腥藻为对象,在单因素实验的基础上,采用响应曲面法考察了壳聚糖(CTS)投加量、聚合氯化铝(PAC)投加量、pH值及CTS和PAC的投加顺序对CTS联合PAC混凝除藻的影响.结果表明,混凝去除铜绿微囊藻(叶绿素a含量为45~55μg/L)的最佳条件为:CTS 0.40mg/L、PAC 1.19mg/L、原水pH值7.5、CTS和PAC混合均匀后投加,该条件下模型预测叶绿素a去除率为96.1%(实测值为95.7%);混凝去除水华鱼腥藻(叶绿素a含量为80~90μg/L)的最佳条件为:CTS 0.25mg/L、PAC 2.00mg/L、原水pH值7.9、先投加CTS后投加PAC,该条件下模型预测叶绿素a去除率为97.9%(实测值为97.0%).当原水pH值9.0时(模拟高藻原水的碱性环境),混凝去除铜绿微囊藻和水华鱼腥藻的最佳投药顺序均为CTS和PAC混合均匀后投加,实测叶绿素a去除率分别为94.9%和95.3%;混凝铜绿微囊藻的药剂方案为CTS 0.40mg/L、PAC 2.00mg/L,药剂成本为0.0215元/m3,混凝水华鱼腥藻的药剂方案为CTS 0.24mg/L、PAC 2.00mg/L,药剂成本为0.0149元/m3.  相似文献   

8.
RT-PCR, nucleotide sequencing, and phylogenetic analysis were performed for genotyping and molecular characterization of noroviruses isolated from Korean groundwater. Among 160 samples collected from 80 sites between 2008 and 2010, 14 samples (8.7?%) from 12 sites were positive for noroviruses (NoVs). The percentages of NoV-positive samples in 2008, 2009, and 2010 were 22.2, 3.2, and 0?%, respectively, representing a yearly decrease. GII-positive samples (n?=?9, 5.6?%) outnumbered GI-positive samples (n?=?5, 3.1?%). The genotypes of the GI NoVs were GI.2, GI.5, and GI.6, and the genotypes of the GII NoVs were all GII.4. One sample, HM623465, was very similar to CUK-3 and CBNU2 and two GII.4 sequences isolated from the stool of Korean gastroenteritis patients. A BLASTN search revealed several nucleotide sequences highly similar to those of NoVs isolated in this study. The original isolation sources for these similar NoVs were mostly stool (n?=?731, 80.0?%) and groundwater (n?=?135, 14.8?%), and all the countries from which they were isolated were almost in Asia (96.0?%); specifically, China (n?=?192, 21.0?%), Japan (n?=?383, 41.9?%), Korea (n?=?296, 32.4?%), and other Asian countries (n?=?6, 0.7?%). These results suggest that Korean groundwater might be contaminated with NoVs from the stool of infected patients and that these NoVs in turn cause new cases of gastroenteritis through a typical fecal-oral route with region-specific circulation. Therefore, it is important to properly treat sewage, which may include waterborne viruses and manage point sources in groundwater for national health and sanitation. In addition, continuous molecular surveillance remains important for understanding circulating NoVs.  相似文献   

9.
通过正交实验制备了阳离子絮凝剂壳聚糖季铵盐(HTCC),研究了壳聚糖季铵盐与聚合氯化铝(PAC)复配对黄河兰州段水的除浊效果,确定最佳复配比为m(HTCC)∶m(PAC)=1∶3。按该复配比,且在最佳投加量(1.25 mg/LHTCC+3.75 mg/L PAC)下,原浊为27.85~33.28 NTU的黄河水经处理后余浊<3 NTU。实验结果表明:pH对HTCC/PAC的除浊效果影响较大,当pH为7~9时,除浊效果均良好;而当pH为5~7时,投药范围内的最佳投药量提前,而除浊效率有所降低;沉降时间对HTCC/PAC的除浊效果无明显影响;HTCC/PAC以固-固方式复配的除浊效果比液-液方式复配的较差。  相似文献   

10.
于琪  胡勇有  雷志斌 《环境科学学报》2013,33(11):2999-3006
采用水溶液自由基聚合反应,将丙烯酰胺(AM)、二甲基二烯丙基氯化铵(DMDAAC)接枝到壳聚糖分子上制成了阳离子改性壳聚糖(CAD).经FT-IR、XRD、zeta(ξ)电位、凝胶色谱等分析确定,CAD为淡黄色透明液体,pH值为3.7,相对分子质量为2.88×106,阳离子度为16.7,等电点(0.1%溶液)约为pH值10.5,有效成分2.6%,主要特征官能团有羟基、氨基、季铵基和酰胺基, 呈不规则晶体结构.将CAD与相对分子质量3.67×105的多糖类电负性微生物絮凝剂MBF8复配,对浊度12~460 NTU、离子强度3.0 mmol·L-1的高岭土悬浊液进行烧杯实验.结果表明,MBF8与CAD的最佳使用方式为先投加MBF8后投加CAD,复配比5:3时效果最好,适用的pH范围为6.0~10.0.采用PAC(3.0 mg·L-1)+MBF8+CAD(1.0 mg·L-1)复配絮凝,pH=8.0下,对浊度为110 NTU的高岭土悬浊液,浊度去除率>97%,残余铝<0.08 mg·L-1,絮体大、沉降快,絮凝效果优于PAC+分子量800万、1200万的阴离子PAM及分子量1500万的阳离子PAM.  相似文献   

11.
聚合氯化铝去除污泥水中磷的工艺优化   总被引:1,自引:1,他引:1  
在对比聚合氯化铝(PAC)对浓缩脱水污泥水及其上清液除磷效果的基础上,通过响应曲面法(RSM)分析了污泥水上清液PAC除磷过程中Al/P摩尔比、pH和搅拌转速(MS)对除磷效果的单独效应和联合效应,并探讨了PAC除磷动力学.结果表明,PAC直接对污泥水混凝除磷会恶化其沉降性能,且除磷效率不高.RSM优化得到的上清液除磷最优工艺条件为:Al/P摩尔比为2.49,pH为8.3,MS为398 r·min-1,除磷效率为97.8%,实验验证结果表明该优化操作模式行之有效.动力学分析结果表明,PAC对污泥水的除磷过程分为化学沉淀与絮凝体快速吸附除磷和二级动力学沉淀除磷两阶段.  相似文献   

12.
为实现废粉末活性炭的循环利用,采用水热炭化对吸附处理染料废水产生的废粉末活性炭进行再生,考察了水热炭化再生温度、再生时间、初始pH和再生次数等因素对废粉末活性炭再生效果的影响.结果表明:将320℃的水热条件下反应8 h得到的再生粉末活性炭用于吸附处理染料废水,色度去除率在95%左右,废粉末活性炭再生率可超过60%,且酸性条件下更有利于活性炭再生.经过5次吸附再生循环,废粉末活性炭再生率为55.54%,再生率仅下降6.06%.红外光谱分析结果表明,新粉末活性炭、废粉末活性炭和再生粉末活性炭的官能团种类基本一致;表面官能团Boehm滴定测定结果显示,再生粉末活性炭表面碱性基团含量降低、酸性基团含量增加.由于升温改变了废粉末活性炭的吸附平衡,有机物从其表面脱附,部分有机物在再生液中降解;此外,废粉末活性炭表面不易挥发和脱附的有机物在高温高压下炭化所得的产物能进一步吸附有机物,因此导致了废粉末活性炭的再生.研究显示,水热炭化对废粉末活性炭有较好的再生效果,具有实际应用价值.   相似文献   

13.
通过盆栽模拟试验研究了不同磷石膏(PG)添加量(0、20、40g·kg-1)和接种3种丛枝菌根真菌(Glomus mosseae(GM)、Glomus aggregatum(GA)、Diversispora spurcum(DS))对玉米生长及其磷、硫、砷吸收的影响.试验结果表明:随磷石膏添加量的提高,土壤有效磷、有效...  相似文献   

14.
混凝过程中铝与聚合铝水解形态的动力学转化及其稳定性   总被引:17,自引:3,他引:17  
采用Ferron逐时络合比色法,并结合电泳测定研究了混凝过程中氯化铝和聚合氯化铝的水解形态动力学转化及稳定性。结果表明,AC在混凝过程中所形成的水解形态完全不同于PAC的预制水解聚合形态,其电荷及分子量均明显低于聚合铝且不稳定,AC随混凝条件如投加浓度、PH和混合时间而变,而PAC-25水解聚合形态不随混凝条件变化,始终保持稳定状态,AC水解沉淀规律与理论计算相符并形成无定形Al(OH)3絮体颗粒  相似文献   

15.
王郑  仲米贵  黄雷  薛侨  林子增  陈蕾 《环境工程》2017,35(10):61-65
研究了聚合氯化铝-壳聚糖(PAC-CTS)絮凝剂的絮凝特性,进行了聚合氯化铝-壳聚糖复合絮凝剂和单独聚合氯化铝对水中溶解态腐殖酸的去除实验。结果表明:复合絮凝剂在投加量为80 mg/L时即可达到与单独聚合氯化铝投加量为150 mg/L时的去除效果,同时前者适应的pH值范围更宽;与投加量和pH值相比,水样浊度和絮凝搅拌速度是影响絮凝效果的次要因素;另外红外光谱分析发现复合絮凝剂中壳聚糖与聚合氯化铝之间存在相互作用。  相似文献   

16.
Al_b形态处理模拟染料废水的效果及机制研究   总被引:2,自引:2,他引:0  
采用乙醇-丙酮混合沉淀法分离聚合氯化铝(PAC)溶液中的Alb形态.通过对吸光度和Zeta电位的测定,研究了Alb形态的投加量和溶液pH对分散黄棕和直接紫2种模拟染料废水脱色效果的影响,并将其与PAC进行比较.利用光散射颗粒分析仪(PDA2000)和Mastersizer2000型激光粒度仪在线测定絮体粒径的变化情况,结合絮体的Zeta电位,对Alb形态的絮凝机制进行探讨.结果表明,与PAC比较,Alb形态处理模拟染料废水的最佳pH值范围较宽,在实验条件下,Alb形态形成的絮体的密实性较高,沉降性能较好,恢复能力较强.  相似文献   

17.
利用造粒流化床技术进行了洗车废水回用处理的实验研究.考察了投药量、污泥床对出水浊度的影响。实验结果表明,使用聚合氯化铝(PAC)为凝聚剂,投加量为45mg/L,聚丙烯酰胺(PAM)为絮凝剂,投加量为3mg/L,搅拌速度为60r/min,水流速度8m/h的条件下,出水浊度小于2度,COD_(Cr)为28mg/L_(?)达到生活杂用水水质标准的要求。该装置运行状态稳定、污泥含水率低,无需浓缩设备,能满足连续处理和间歇处理的需要。  相似文献   

18.
郭俊元  赵净  付琳 《中国环境科学》2016,36(11):3360-3367
采用水稻秸秆制备微生物絮凝剂,研究了微生物絮凝剂对污泥脱水性能的影响,并通过响应面分析法优化了微生物絮凝剂与聚合氯化铝(Polyaluminum chloride,PAC)复配改善污泥脱水性能的过程.结果表明,制备微生物絮凝剂的最佳条件为:800mL蒸馏水、200mL水稻秸秆酸解液、4g K2HPO4、2g KH2PO4、0.2g MgSO4、0.1g NaCl、2g尿素,在此条件下,微生物絮凝剂产量达0.96g/L.保持原污泥pH值,当微生物絮凝剂投加量为12mg/L,干污泥量(DS)较原污泥提高了59.5%,污泥比阻(SRF)降低了53.6%,表明经微生物絮凝剂絮凝处理,污泥脱水性能显著改善.保持原污泥pH值,当PAC投加量为3g/L,干污泥量(DS)为16.4%,高于原污泥的13.2%,污泥比阻为(SRF)5.4×1012m/kg,低于原污泥的11.3×1012m/kg,说明PAC对污泥脱水性能有着明显的改善作用.响应面分析结果显示,污泥脱水最佳条件为微生物絮凝剂8.1mg/L、PAC 1.9g/L、pH值8.0,相应DS和SRF分别为24.1%和3.0×1012m/kg.实际污泥脱水工程中,污泥pH往往不进行调节,保持原污泥pH=6.4条件下,DS和SRF分别为23.6%和3.2×1012m/kg,均优于单独采用微生物絮凝剂和PAC时的污泥脱水效果.  相似文献   

19.
羧甲基壳聚糖及复合絮凝剂对染料废水的脱色研究   总被引:1,自引:0,他引:1  
用羧甲基壳聚糖(CMCTS)复合聚合氯化铝(PAC)对分子量较小的活性染料模拟废水进行脱色处理,结果表明,引入PAC作为助凝剂的脱色效果优于单纯使用CMCTS。处理染料废水的最佳pH为5,CMCTS的投加量为90mg/L,PAC的投加量为2.5mg/L,此优化条件下,染料废水的脱色率可达93.4%,COD去除率达88.5%。  相似文献   

20.
垃圾渗滤液的混疑处理实验研究   总被引:15,自引:0,他引:15  
用聚合氯化铝(PAC).聚丙烯酰胺(PAM).复合混凝剂(90%PAC 10%PAM)及试剂A(一种壳聚糖)等4种混凝剂在不同pH及不同投加量的情况下.对垃圾渗滤液COD的去除效果进行了比较分析。实验结果表明。复合混凝剂及试剂A的处理效果明显优于PACPAM。在pH值5.5和8时。复合混凝剂投加量为400mg/L时。COD的去除率分别为38.63%和37.84%:试剂A在pH为8.投加量为100mg/L时。对COD的去除率达到39.85%。  相似文献   

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