以PHAs为固体碳源的城镇二级出水深度脱氮研究

利用从连续运行的缓释碳源滤料滤池中取出的聚羟基脂肪酸酯(PHAs)颗粒,研究了微生物和硝酸盐对其的总有机碳(TOC)释放速率的影响,并研究了温度、pH值、硝态氮浓度对其反硝化速率的影响.结果表明:原有的和附着有微生物的PHAs颗粒在去离子水中TOC释放速率分别为0.030,0.053mg/(g·d),远低于水中有硝酸盐时的TOC释放速率[进水NO3--N为30mg/L时,TOC释放速率为0.533mg/(g·d)].温度和pH值对反硝化速率影响较大, pH值为7.5时,在15~35℃范围内, 30℃下的反硝化速率最大,为0.067mg/(g·h);温度为30℃时,pH值在6.0~9.0范围内,pH值为7.8时的反硝化速率最大,达到0.061mg/(g·h).反硝化速率与NO3--N浓度之间的关系符合Monod方程,最大反应速率和半饱和常数分别为4.74mgNO3--N/(gSS·h)和56.6mg/L.     

胞外多聚物在好氧颗粒化中的作用机理

在上流式反应器中培养好氧颗粒污泥,研究胞外多聚物在好氧颗粒污泥中的作用.结果表明,胞外多聚物有机组成中蛋白质与总糖的比值在颗粒污泥形成过程中增加了近2.5倍,它是影响颗粒污泥形成的重要因素.蛋白质与总糖比值增加,则污泥表面负电荷降低、疏水性增加,有利于好氧颗粒污泥的形成和稳定.     

双模板分子印迹微球的制备及其在海水溶液中的分子识别行为研究

以萘和蒽为双模板分子,以甲基丙烯酸为功能单体、二甲基丙烯酸乙二醇酯为交联剂、聚乙烯醇（PVA）为分散剂,通过悬浮聚合制备了双模板分子印迹微球.采用紫外光谱法分析了双模板分子印迹效应产生的机制,用静态吸附实验考察了印迹微球对海水中2—3环多环芳烃的吸附选择性,并以分子印迹-分散固相微萃取法分析了海水中2—3环的多环芳烃.结果表明,双模板-功能单体分子间的多位点协同作用,优化了分子印迹材料的印迹孔穴,提高了双模板分子印迹微球的分子识别能力;所制备的双模板分子印迹材料使用3次后其选择识别性能未显著降低,显示出其富集与分离海水样品中2—3环多环芳烃的良好前景.     

环糊精多孔聚合物对水中染料分子的吸附性能及主客效应

环糊精能够与多种有机污染物形成主-客体包合物,对去除水中种类复杂的染料分子具有独特的优势.利用刚性交联剂交联制备出了环糊精多孔聚合物(P-CDP),借助FT-IR、XPS、SEM和BET等技术对P-CDP结构进行表征,采用等温吸附和动力学吸附实验研究P-CDP对染料的吸附过程,并通过竞争实验探究P-CDP对水中染料分子...     

Magnetic molecularly imprinted polymer prepared by microwave heating for confirmatory determination of chloramphenicol in chicken feed using high-performance liquid chromatography-tandem mass spectrometry

Abstract

A magnetic molecularly imprinted polymer (MMIP) for chloramphenicol was prepared using a surface-imprinted and microwave-heating-induced polymerization method. The surfaces of the magnetic particles were first double-bond functionalized with 3-(trimethoxysilyl)propyl methacrylate (γ-MPS), followed by the copolymerization of 4-vinyl pyridine (4-VP) and trimethylolpropane trimethacrylate (TRIM) in the presence of chloramphenicol as a template and 1,1-azobis(cyclohexane-carbonitrile) (ABCN) as an initiator in a mixture of dimethyl sulfoxide and water with microwave heating at 80°C. The magnetic polymer possesses supraparamagnetic properties and was used to concentrate and cleanup chicken feed extract, followed by chromatographic separation using a Lichrospher®100 RP C8 column and detection with two multi-reaction monitoring transitions at m/z 321→ 152 and m/z 321→ 257. The mean recoveries obtained at two spiking levels were in the range of 94.6–100% The relative intra- and inter-day standard deviations were in the range of 1.4–2.6% and 5.1–5.7%, respectively. The detection limit of the method was 0.12 µg kg^?1. This confirmatory method was successfully applied to determine chloramphenicol in chicken feed samples.     

苯酚分子印迹聚合物的合成、表征及吸附性能研究

以苯酚为模板,2-Vpy为功能单体,EGDMA为交联剂,采用本体聚合方式在氯仿溶剂中合成了一系列分子印迹聚合物,并通过静态吸附实验对聚合物的选择吸附性进行评价.结果显示,以氯仿作为致孔剂,模板分子与功能单体的摩尔比为1∶2时,聚合物对模板分子的印迹因子为3.96,最大表现结合量(Qmax)为120.7 mmol/g,具...     

量子点在环境污染物检测中的应用进展

作为一类理想的荧光探针，量子点近年来在环境污染物定性定量分析方面的应用取得了很大进展，为环境监测提供了一种新的方法和技术，显示出极大的优越性。综述了量子点分子印迹、量子点自组装膜、双色量子点比率荧光传感等新技术在国内外环境污染物检测方面的研究进展，并对其发展前景作了展望。     

饮用水中苯基脲除草剂的分子印迹固相萃取方法研究

以N-（4-异丙基苯基）-N-亚丁基脲分子印迹聚合物为吸附剂，建立了饮用水中苯基脲除草剂的分子印迹固相萃取方法。上样后固相萃取柱依次用2．5mL0．1mol／L盐酸和2．5mL去离子水淋洗，然后氮气吹干，再用1mL含8％乙腈的甲苯溶液淋洗，最后用2mL甲醇洗脱。将建立的方法用于自来水中异丙隆、非草隆、甲氧隆、绿麦隆、枯莠隆、灭草隆、伏草隆、草不隆等8种苯脲类除草剂的测定，除伏草隆和草不隆的回收率较低外，其余6种除草剂的回收率均〉60％。     

Selective removal of 2,4-dichlorophenol from contaminated water using non-covalent imprinted microspheres

A molecularly imprinted polymer (MIP) for selective removal of 2,4-dichlorophenol (2,4-DCP) in water was prepared as microspheres by the reverse microemulsion polymerization method based on the non-covalent interactions between 2,4-DCP, oleic acid, and divinylbenzene in acetonitrile. Microspheres have been characterized by Fourier transform infrared spectrometer (FTIR) and energy dispersive X-ray spectrometer (EDS) studies with evidence of 2,4-DCP linkage in polymer particles and scanning electron microscopy (SEM) to study their morphological properties. The proper adsorption and selective recognition ability of the MIP were studied by an equilibrium-adsorption method. The MIP showed outstanding affinity towards 2,4-DCP in aqueous solution and the optimum pH value for binding has been found around the neutral range. The molecular recognition of 2,4-DCP was analyzed in detail by using molecular modeling software. In addition, by investigating the variation in the adsorption ability of the MIP, it clearly showed excellent reproducibility.     

Mechanical Property and Biodegradability of Cast Films Prepared from Blends of Oppositely Charged Biopolymers

Biodegradable cast films of about 50 m thickness were fabricated by blending oppositely charged biopolymers such as anionic starch–chitosan, and cationic starch–pectin. The tensile strength and elongation at break (%) of films were evaluated as well as their capacity to degrade in compost. Films recovered from soil every 48 h showed consistent degradation (weight loss), diminution of the polymers characteristic peak absorbance in the carbohydrate fingerprint region of the FTIR, and changes in the surface morphology via scanning electron microscopy (SEM). Anionic starch–chitosan films had much superior tensile strength and elongation compared to cationic starch–pectin, suggesting that the ionic bonds formed between anionic-starch and positively charged groups in chitosan polymer were much more stable and stronger. Initially, both films lost about 36% weight within 96 h, which also correlated well with the loss in the characteristic absorption peaks in the region of the infrared spectrum typical of biopolymers. The total mineralization of films by microorganisms in compost soil was also measured using respirometric techniques. Though the rate of mineralization differed for two formulations, total mineralization (extent) for both films were achieved within 45 days.