检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
作 者:张志超[1] 黄霞[1] 杨海军[2] 肖康[1] 罗小[2] 沙恒[1] 陈奕名[1]
机构地区:[1]清华大学环境科学与工程系环境模拟与污染控制国家重点联合实验室,北京100084 [2]清华大学化学系,北京100084
出 处:《光谱学与光谱分析》2009年第2期536-539,共4页Spectroscopy and Spectral Analysis
基 金:国家杰出青年基金项目(50725827)资助
摘 要:利用31P-NMR研究了生物除磷污泥胞外多聚物(EPS)的含磷形态,并对检测方法中的影响因素进行了分析。研究发现,测定的三种污泥EPS中磷的形态有五种,磷酸盐、磷单脂、DNA磷、聚磷末端、焦磷酸盐和聚磷。具有除磷能力的A/A/O和A/A/O-MBR污泥其EPS中主要含的是聚磷,证明了EPS中含磷不仅是依靠吸附磷酸盐或生物聚磷过程磷酸盐的滞留,而且EPS本身可能也参与了生物聚磷过程。同时实验证明,EPS提取过程会对EPS含磷形态产生影响,但提取时间在1h内时影响较小;EPS在储存前需要进行中和,从而避免储存过程不同磷形态之间的转化。EPS含磷形态的31P-NMR测定过程中,EPS样品的pH值对峰的分离和各峰化学位移的稳定性有较大影响,需要控制样品pH>13.0以确保测定过程的准确性。The present paper investigated phosphorus forms in the extracellular polymeric substances (EPS) using ^31 P-NMR spectroscopy, and analyzed the influential parameters for this method. The results showed that in the three investigated EPS samples five P forms were identified, including orthophosphate, orthophosphate monoesters, DNA, pyrophosphate and polyphosphate. And in the EPS extracted from A/A/O sludge and A/A/O-MBR sludge polyphosphate was the main phosphorus form. This indicatedthat P is contained in the EPS not only owing to the adsorption of orthophosphate, but also because EPS acting like the bacteria cells contributes to enhanced biological phosphorus removal. Furthermore the transformation of P forms in the EPS during the EPS extraction was found but limited within I h. It was found that with the NaOH solution added the polyphosphate in the EPS would partly convert to pyrophosphate but not go further to orthophosphate, while with pure water added P forms in the EPS were very stable. This means that after neutralization, the transformation of phosphorus forms could be avoided. Since the measurement of ^31 P-NMR spectroscopy was very sensitive to pH, which could affect the chemical shift of the peaks and cause peaks overlapping, the pH of EPS sample must be raised to 13.0 before the measurement.
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:216.73.216.117