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121.
考察了树脂法提取活性污泥中胞外聚合物(extracellular polymeric substance,EPS)的影响因素,确定了最佳的提取条件.试验结果表明,树脂量60g/g VSS,振摇频率200r/min下处理4 h,EPS的提取量达到111.20 mg/L,DNA占提取量的12.13%.该方法的重现性试验结果还表明,EPS及其各成分的相对标准偏差在2.21%~6.07%之间,能较好地满足试验要求,是一种可靠的EPS提取方法.  相似文献   
122.
本文研究了N_(1923)萃淋树脂对汞(Ⅱ)吸萃的性能、溶液的酸效应、吸附等温线、吸附速率及体系温度等对吸萃分配比的影响.用饱和容量法、等摩尔系列法、斜率法等对吸萃物组成进行了探讨.并用红外光谱法、核磁共振谱法对吸萃机理进行了分析.  相似文献   
123.
Acid hydrolysis of estuarine water samples for the determination of amino acids (AAs) was tested and found to be effective at high (250 μM) nitrate concentrations when the anti-oxidant, ascorbic acid, was added to the samples. Hydrolysable AA concentrations were then determined in surface sediments collected from low and high salinity regions of the Tamar Estuary (UK) during winter 2003 and 2004, and in overlying water when simulated resuspension of sediment particles was performed. Concentrations of AAs in sediment samples comprised <50% of particulate nitrogen, fitting the paradigm that most sedimentary nitrogen is preserved within an organic matrix. When sediment samples were resuspended in overlying water (salinity 17.5), the rapid, measured increase in dissolved AA concentrations almost equalled the reported nitrate concentration in the lower estuary, with the subsequent decrease in the total dissolved AA levels suggested that bacterial uptake was occurring. Our data concur with previous studies on nitrogen desorption from sediments and suggest that an understanding of organic nitrogen cycling will be an important aspect of future effective estuarine management.  相似文献   
124.
NKA-Ⅱ型大孔吸附树脂处理苯胺废水的研究   总被引:2,自引:0,他引:2  
针对苯胺废水的特点,利用NKA-Ⅱ大孔吸附树脂进行处理,研究了苯胺废水质量浓度、pH值、温度和流速等因素对大孔吸附树脂动态吸附-脱附性能的影响,并得到了最佳工艺条件。实验结果表明在最佳工艺条件下,苯胺去除率>99%,COD>98%,出水苯胺的质量浓度<40mg·L-1,COD出水的质量浓度<100mg·L-1,树脂的平均脱附率值接近99.7%。在废水得到有效处理的同时,苯胺资源也得到了回收,达到了废水治理与资源化的效果。  相似文献   
125.
针对纺织品中甲醛超量的问题,提出了降低多羟树脂中游离及释放甲醛的方法和对策。  相似文献   
126.
离子交换树脂吸附Cd(Ⅱ)和Pb(Ⅱ)的研究   总被引:1,自引:0,他引:1  
采用静态法和动态法对阳离子交换树脂吸附Cd(Ⅱ)、Pb(Ⅱ)的行为进行了研究。考察了pH值、流速、吸附时间等条件对吸附效果的影响,优化了树脂洗脱再生的最佳条件。实验结果表明,732型强酸阳离子交换树脂能够有效地吸附废水中的Cd(Ⅱ)和Pb(Ⅱ)。对比两种交换方式,动态法具有操作简单、效率高、可连续运行等特点,具有较高的实用价值。  相似文献   
127.
采用XAD树脂吸附法,在春季内(3~5月)连续对南方深圳水库中的水体溶解性有机物(DOM)进行化学分级表征.结果表明,天然水体DOM的总量和单个化学分级组分含量在一个季节会发生一定的波动,但总的分布特征在季节内未发生根本变化,即憎水酸(HoA)和亲水部分(HiM)浓度始终较高,而憎水碱(HoB)、憎水中性物(HoN)、弱憎水酸(WHoA)浓度则相对较低.同时,选取代表性时间点对DOM各化学分级组分进行了消毒副产物三卤甲烷生成势(THMFP)的研究,发现三卤甲烷(THMs)的主要前驱物为憎水和弱憎水有机部分,对THMFP的贡献共占约80%.进一步研究发现,憎水中性物、憎水酸、弱憎水酸的THMs生成能力较强,总体上与紫外吸收能力基本一致;但弱憎水酸表现略有不同,其SUVA(100×UV254/DOC)值并不十分突出,但三卤甲烷生成能力却明显较高,说明DOM的紫外吸收特性不能完全作为THMFP特性的替代指标.亲水物质(HiM)的SUVA值也不高,但其THMs生成能力接近憎水酸部分,值得水处理工艺研究重点关注.  相似文献   
128.
使用SUMMA罐采集华东地区5类典型合成树脂企业有组织排口样品,通过气相色质联用技术(GC-MS)定量分析106种VOCs,计算了合成树脂行业排放量、排放系数和不确定性,分析了VOCs的排放特征和臭氧生成潜势,建立了5类合成树脂VOCs排放成分谱.结果表明:合成树脂企业VOCs排放量为346~3467kg/a,5类合成树脂排放系数为0.06~1.24g/kg,其中涂料树脂(CR)类企业排放量和排放系数均最大.芳香烃、含氧烃(OVOCs)和卤代烃是合成树脂行业VOCs排放基本组分,累计占比范围是73.2%~98.3%.涂料树脂、酚醛树脂(PF)、聚氨酯(PU)、共聚物树脂(ABS)和聚碳酸酯(PC)特征污染物分别为:甲基异丁基酮、苯、甲苯、苯乙烯和二氯甲烷.合成树脂企业臭氧生成潜势(OFP)为22.7~202.5mg/m3,源反应性(SR)为0.3~4.6g/g,CR类企业OFP和SR均最大.合成树脂行业SR处于各行业平均水平.芳香烃、OVOCs和烯炔烃是合成树脂行业的主要光化学活性组分,累计OFP贡献率为64.1%~100.0%,苯、甲苯、甲基异丁基酮、乙烯、苯乙烯是合成树脂行业关键活性物种.研究显示,合成树脂行业VOCs治理应管控芳香烃和OVOCs的排放,重视污染物恶臭问题和卤代烃溶剂的危害,减排VOCs排放量大、臭氧生成能力强的CR类企业.  相似文献   
129.
Regeneration of pure water is an important issue not only for the healthy life but also for the fine control of precise processes in various industries.One important issue in ultrahigh purified water is to reduce the amount of total organic carbon(TOC).Herein,we introduce a new approach to reduce the TOC using the surface silanized nanoparticles,in which the magnetic nanoparticles(mNPs) are silanized and then complexed with ion exchange resin(IER) beads.The Fe_3O_4 mNPs are surface modified by using high concentrated vinyltrimethoxysilane(VTMS) and then adhered on the surface of IER beads.The surface modified mNPs have a thick-shell of polysiloxane layer varying from 5 to 22 nm depending on the amount of VTMS used,which leads the significant increase of specific surface area.The IER beads embedding VTMS-silanized mNPs achieves about 7 μg/L of the TOC level in ultrapure water system,which is two orders less than 228 μg/L of the feeding water and one order less than 96 μg/L from the system using pristine IER beads.This result is mainly attributed to the polysiloxane layer forming broccoli-like surface structure and some part by the vinyl group of VTMS exposed to the amines in the water.  相似文献   
130.
Phytoremediation is a valuable technology for mitigating soil contamination in agricultural lands, but phytoremediation without economic revenue is unfeasible for land owners and farmers. The use of crops with high biomass and bioenergy for phytoremediation is a unique strategy to derive supplementary benefits along with remediation activities. Sunflower (Helianthus annuus L.) is a high-biomass crop that can be used for the phytoremediation of polluted lands with additional advantages (biomass and oil). In this study, 40 germplasms of sunflower were screened in field conditions for phytoremediation with the possibility for oil and meal production. The study was carried out to the physiological maturity stage. All studied germplasms mopped up substantial concentrations of Pb, with maximum amounts in shoot?>?root?>?seed respectively. The phytoextraction efficiency of the germplasm was assessed in terms of the Transfer factor (TF), Metal removal efficiency (MRE) and Metal extraction ratio (MER). Among all assessed criteria, GP.8585 was found to be most appropriate for restoring moderately Pb-contaminated soil accompanied with providing high biomass and high yield production. The Pb content in the oil of GP.8585 was below the Food safety standard of China, with 59.5% oleic acid and 32.1% linoleic acid. Moreover, amino acid analysis in meal illustrated significant differences among essential and non-essential amino acids. Glutamic acid was found in the highest percentage (22.4%), whereas cysteine in the lowest percentage (1.3%). Therefore, its efficient phytoextraction ability and good quality edible oil and meal production makes GP.8585 the most convenient sunflower germplasm for phytoremediation of moderately Pb-contaminated soil, with fringe benefits to farmers and landowners.  相似文献   
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