V2O5-TiO2-AlF3/Al2O3催化臭氧化2,4-滴丙酸的氧化效能

为了提高有机物的臭氧化降解效率,工作中利用浸渍法制备了一种新型的三组分催化剂(记为V2O5-TiO2-AlF3/Al2O3)。催化臭氧化降解2,4-滴丙酸的实验结果表明,该催化剂能有效提高臭氧化的效率,体系可能遵循羟基自由基的作用机理。利用相对法计算结果表明,与单独臭氧化相比,V2O5-TiO2-AlF3/Al2O3催化臭氧化体系具有更大的Rct值。重复实验结果表明,该催化剂具有相对较好的稳定性。以上研究结果对推广催化臭氧化技术在实际废水处理中的应用具有重要的实际意义。     

Oxidation of Cyclic Ethers by Alkane‐Grown Mycobacterium vaccae JOB5

In this study we investigated the cometabolic oxidation of six cyclic ethers by alkane‐grown Mycobacterium vaccae JOB5. These ethers include, among others, tetrahydrofuran (THF), 1,4‐dioxane (14D), 1,3‐dioxolane (13DO), and tetrahydropyran (THP). Cells grown on propane, n‐butane, n‐pentane, isobutane, or isopentane oxidized all six ethers. Ether‐degrading activity was inhibited by acetylene in alkane‐grown cells and was largely absent from cells grown on dextrose‐containing media. Propane competitively inhibited THF oxidation. γ‐Butyrolactone (γBL) accumulated and was also further oxidized during THF oxidation by propane‐grown cells. In contrast, no products were detected during 14D oxidation. Propane‐grown cells also rapidly oxidized 3‐hydroxytertrahydrofuran and exhibited strong hemiacetal‐oxidizing activity in an assay following methyl formate production from mixtures of methanol and formaldehyde. These observations suggest γBL is likely generated during THF oxidation through further oxidation of 2‐hydroxytetrahydrofuran. Limited growth of strain JOB5 was supported by several cyclic ethers and the corresponding lactones and diols potentially derived from these compounds. However, strain JOB5 grew more readily on 4‐hydroxybutyrate, the product of γBL hydrolysis. The ability of strain JOB5 to productively assimilate THF‐derived metabolites during growth on n‐alkanes was examined in carbon‐limited batch cultures. Relative to C‐limited growth on n‐pentane alone, culture growth increased up to twofold in the presence of THF while no stimulation of growth was observed in comparable experiments conducted with n‐pentane and 14D. Our results are discussed in terms of their significance to our understanding of cyclic ether cometabolism and their potential impact on approaches for cyclic ether biodegradation in the environment. © 2013 Wiley Periodicals, Inc.     

Roles of Scholars in the Practice of Combating-Desertification: A Case Study in Northwest China

This study investigated the perceived importance of scholars’ participation in combating-desertification programs in northwest China and analyzed the underlying factors and mechanisms. Our results show that, while various experts, professors, and researchers have participated in combating-desertification programs, their actions were often not effective. Only those scholars who understood the local situations adequately had important and positive impacts. These scholars served as information brokers between the governments and other stakeholders, entrepreneurial activity organizers for farmers, governmental representatives, or advocators for local affairs themselves. They played indispensible roles in facilitating efforts in combating desertification. The study also identified key factors that led to the success of scholars’ participation in combating-desertification activities. Our findings have practical implications for improving the effectiveness of scholars’ participation in land restoration and environmental management.     

Pentachlorophenol induced physiological-biochemical changes in Chlorella pyrenoidosa culture

Present study investigated physiological and biochemical changes in a green alga culture (Chlorella pyrenoidosa) upon exposure to varied concentrations of pentachlorophenol (PCP) (0, 0.4 mgL(-1), 2.5 mgL(-1) and 10 mgL(-1)). The results revealed that with the increase of PCP concentration, a decrease of the algal biomass, levels of photosynthetic pigments (chlorophyll a, b and carotenoid), soluble protein and an increase of nitrate reductase (NR) activity were observed. This suggests that the PCP may serve as an uncoupler, causing low ATP level within the algal cells and led most of the NR molecules to be in the dephosphoration state (i.e. active from). Moreover, it shows that photosynthetic pigments especially carotenoid were more sensitive indicators to indicate PCP toxicity as compared to the other parameters.     

堆码试验标准差异的探讨与应用

本文介绍GJB 2711-1996中方法 13、方法 14两种堆码试验方法的异同点,以及它们与现行国家标准GB/T 4857.3-2008及GB/T 4857.4-2008中两种堆码试验方法的比较,说明堆码试验方法在国军标与国标中的共同点和差异,以及堆码试验中需要关注的问题。     

3×300t转炉二次除尘系统扩容改造

针对宝钢一炼钢3×300t转炉二次烟气严重污染室内外环境的实际情况,在兼顾节能与减排的协同原则下,确定了对原转炉二次除尘系统的扩容改造方案。竣工投运后,取得了良好的环保、节能效果。     

鄱阳湖老爷庙水域细菌群落组成分析

通过提取鄱阳湖老爷庙水域水体细菌总DNA, 构建细菌16SrRNA基因文库和序列测定等手段,以期揭示鄱阳湖老爷庙水域的细菌群落组成并探讨细菌多样性与湖泊水体理化参数之间的关系。研究结果认为：来自老爷庙水域的2006年10月（PN06 10）和2007年5月 (PN07 5) 的细菌文库中的180个阳性克隆产生了66个细菌分类操作单位（OTUs）,这些细菌主要分属于：变形菌Alpha 纲,Beta 纲,Gamma 纲,Epsilon 纲,拟杆菌门,放线菌门,浮霉菌门,酸杆菌门和OP10等9大类型。2006年10月老爷庙水域的优势菌群为Beta 变形菌;2007年5月优势菌群为Gamma 变形菌和拟杆菌,表明鄱阳湖细菌组成在不同的季节显著不同。进一步系统发育分析表明：大部分细菌的最相似序列来源于淡水,湖泊和土壤的未培养细菌,且部分细菌与环境污染物降解有关     

金属镁渣的回收利用现状

近年来,我国镁冶炼行业快速发展,随着原镁和镁合金年产量的逐年增高,排放出来的镁渣也越来越多,如何有效合理地处理、开发利用镁渣,达到节约能源、节约资源、变废为宝和变害为利的目的,是当前迫切需要解决的问题。对近年来我国有关镁渣的研究应用情况进行全面的总结。     

发酵-渗透汽化膜技术制无水乙醇研究进展

渗透汽化膜技术作为一种新型的膜分离技术和清洁生产技术,与发酵法相耦合生产燃料乙醇,具有高效、节能和环保的优势。综述了发酵-渗透汽化膜技术的研究进展,介绍了该工艺动力学模型的研究成果,与传统的发酵法进行了经济性对比,阐述了渗透汽化膜技术应用于无水乙醇工业化生产的现状和存在的问题,展望了发酵-渗透汽化膜技术的研究方向。