基于可見光催化的腐皮鐮刀菌滅活機(jī)制與光催化燃料電池研究
發(fā)布時(shí)間:2018-04-03 05:09
本文選題:活性物種 切入點(diǎn):可見光 出處:《吉林大學(xué)》2017年碩士論文
【摘要】:城市污水在經(jīng)處理后,水中的病原微生物仍大量存在,鐮刀菌屬廣泛分布在水和土壤系統(tǒng)中,會(huì)引起植物根,莖和花的腐爛。但是,由于其具有較厚的細(xì)胞壁和較強(qiáng)的環(huán)境抗性,腐皮鐮刀菌形成的孢子細(xì)胞非常難以失活。選擇3種典型的摻雜型TiO_2,即Ag/TiO_2,N/TiO_2和Er~(3+):YAlO_3/TiO_2,對(duì)腐皮鐮刀菌進(jìn)行可見光催化滅殺,采用光學(xué)顯微鏡和透射電鏡、三維熒光光譜、凝膠過濾色譜和掩蔽實(shí)驗(yàn)等手段,確定活性氧物種(ROSs)在鐮刀菌的孢子滅活中的作用。結(jié)果表明,1)Ag/TiO_2光催化產(chǎn)生的ROSs主要是H2O_2,在不同種類的ROSs中具有最長(zhǎng)的壽命。反應(yīng)1 h后,Ag/TiO_2對(duì)腐皮鐮刀菌滅活率接近100%,但失活的腐皮鐮刀菌孢子仍保持完整細(xì)胞壁形狀,生物分子滲漏最小化。2)Er~(3+):YAlO_3/TiO_2由h+占主導(dǎo),反應(yīng)7 h后的滅活率為91.0%,被滅活的腐皮鐮刀菌細(xì)胞壁嚴(yán)重?fù)p傷,隨后Er~(3+):YAlO_3/TiO_2納米顆粒進(jìn)入孢子細(xì)胞并繼續(xù)氧化細(xì)胞內(nèi)物質(zhì)。3)N/TiO_2光催化劑產(chǎn)生的是以·O_2-為主的ROS,7 h后的腐皮鐮刀菌孢子滅活率為94.3%,細(xì)胞壁形狀改變,有細(xì)胞溶出物泄露。因而,H2O_2主導(dǎo)的ROS對(duì)于孢子滅活效果最佳。為了進(jìn)一步實(shí)現(xiàn)有效殺滅腐皮鐮刀菌孢子和能源的回收,本文對(duì)基于Ag/TiO_2的光催化燃料電池(PFC)進(jìn)行了初探。采用旋涂法將Ag/TiO_2涂布到導(dǎo)電玻璃制備PFC光電陽極。通過對(duì)負(fù)載率分別為0.036、0.50、0.75和1.30 wt%電極的I-T曲線、COD去除率、庫倫效率、極化功率密度虛線以及電池內(nèi)阻進(jìn)行測(cè)試,發(fā)現(xiàn)負(fù)載率為0.75 wt%的電極有最高的電化學(xué)特性,其組成的PFC體系在殺滅腐皮鐮刀菌孢子的同時(shí)產(chǎn)生了穩(wěn)定的電流,4 h后,發(fā)現(xiàn)PFC體系中只能檢測(cè)到濃度比較低的腐皮鐮刀菌孢子(50 CFU/m L),而單純的光催化反應(yīng)4小時(shí)后溶液中腐皮鐮刀菌孢子的濃度為215CFU/m L,約為PFC體系中的4倍。
[Abstract]:After treatment of municipal sewage, pathogenic microorganisms still exist in the water. Fusarium is widely distributed in water and soil systems, which will cause rotting of plant roots, stems and flowers.However, due to its thick cell wall and strong environmental resistance, spores formed by Fusarium vulgaris are very difficult to inactivate.Three kinds of typical doped TiOs _ 2, namely, Ag- / TiO2N- / TiO-2 and Er~(3 / YAlO _ 3 / TiO2, were selected to kill Fusarium vulgaris by visible light catalytic killing, using optical microscope and transmission electron microscope, three-dimensional fluorescence spectrum, gel filtration chromatography and masking experiment, etc.To determine the role of reactive oxygen species (Ros) in spores inactivation of Fusarium.The results show that the ROSs produced by photocatalysis is mainly H _ 2O _ 2 and has the longest lifetime among different kinds of ROSs.After one hour of reaction, the inactivation rate of Ag- / TiO-2 to Fusarium vulgaris was close to 100, but the inactivated spores of Fusarium vulgaris remained intact cell wall shape, and bio-molecular leakage minimization.The inactivation rate was 91.0% after 7 h reaction. The cell wall of inactivated Fusarium vulgaris was seriously damaged.闅忓悗Er~(3 ):YAlO_3/TiO_2綰崇背棰楃矑榪涘叆瀛㈠瓙緇嗚優(yōu)騫剁戶緇哀鍖栫粏鑳?yōu)鍐呯墿璐?3)N/TiO_2鍏夊偓鍖栧墏浜х敓鐨勬槸浠ヂ稯_2-涓轟富鐨凴OS,7 h鍚庣殑鑵愮毊闀板垁鑿屽瀛愮伃媧葷巼涓,
本文編號(hào):1703749
本文鏈接:http://sikaile.net/shengtaihuanjingbaohulunwen/1703749.html
最近更新
教材專著