充分利用环保倒逼机制促进产业结构调整升级

淄博市污染聚集,环境质量易受外来因素影响,产业结构不合理,污染物排放量大,排放强度高。但其充分发挥环保的倒逼作用,通过建立健全环保政策法规体系,严格执行高于省及国家标准的地方环保标准,大力发展高新技术和现代服务业,加快改造传统产业,极大地促进了产业结构升级和经济发展方式的转变。     

Photocatalytic oxidation of monuron in the suspension of WO3 under the irradiation of UV-visible light

A comprehensive study of the degradation of monuron, one of the phenylurea herbicides, was conducted by UV-Vis/WO₃ process. It was found that hydroxyl radicals played a major role in the decay of monuron while other radicals (e.g. superoxide) and hole might also contribute to the decomposition of monuron. The oxidation path likely plays a major role in the generation of hydroxyl radicals. The effects of initial pH level, initial concentration of monuron, and inorganic oxidants on the performance of UV-Vis/WO₃ process were also investigated and optimized. Comparison between monuron decay pathways by UV-Vis/WO₃ and UV/TiO₂ was conducted. The decay mechanisms, including N-terminus demethylation, dechlorination and direct hydroxylation on benzene ring, were observed to be involved in the oxidation of monuron in these two processes. Sixteen intermediates were identified during the photodegradation of monuron and degradation pathways were proposed accordingly.     

Catalytic destruction of pentachlorobenzene in simulated flue gas by a V2O5-WO3/TiO2 catalyst

Pentachlorobenzene (PeCB) in simulated flue gas was destructed by a commercial V₂O₅-WO₃/TiO₂ catalyst in this study. The effects of reaction temperature, oxygen concentration, space velocity and some co-existing pollutants on PeCB conversion were investigated. Furthermore, a possible mechanism for the oxidation of PeCB over the vanadium oxide on the catalysts was proposed. Results show that the increase of gas hourly space velocity (GHSV) and the decrease of operating temperature both resulted in the decrease of PeCB removal over the catalyst, while the effect of the oxygen content in the range of 5-20% (v/v) on PeCB conversion was negligible. PeCB decomposition could be obviously affected by the denitration reactions under the conditions because of the positive effect of NO but negative effect of NH₃. The introduction of SO₂ caused the catalyst poisoning, probably due to the sulfur-containing species formed and deposited on the catalyst surface. The PeCB molecules were first adsorbed on the catalyst surface, and then oxidized into the non-aromatic acyclic intermediates, low chlorinated aromatics and maleic anhydride.     

The OH-induced degradation mechanism of 4-chloro-2-methylphenoxyacetic acid (MCPA) with two forms in the water: a DFT comparison

The initial degradation mechanisms of OH and 4-chloro-2-methylphenoxyacetic acid (MCPA) including molecular form and anionic form are studied at the MPWB1K/6-311+G(3df, 2p)//MPWB1K/6-31+G(d, p) level. Possible reaction pathways of H-atom abstraction and OH addition are considered in detail. By result comparison analysis, it is found that the reaction mechanisms for OH and two forms of MCPA are different, and most reactions for anionic MCPA are easier than those for molecular MCPA. For H-atom abstraction reactions, the calculated energies show that OH abstracting H-atom from -CH₃ group of molecular MCPA is the most kinetically favorable process; the potential energy surface for anionic MCPA indicates that H-atom in -CH₂ group is slightly easier to be abstracted than that in -CH₃ group. For OH addition reactions, the addition of OH to the C1 site is the initial step for molecular MCPA and the predominant product is 4-chloro-2-methylphenol (denoted P3), while the C4 site is the most reactive site for anionic MCPA and the primary product results from the hydroxylation of the aromatic ring, which is in good agreement with the experimental observation. In additional, results from PCM calculations show that most reactions in water phase are more kinetically favorable than those in gas phase, though the mechanisms discussed above will not be changed.     

磁性海泡石吸附Cr(VI)特性及动力学

采用化学共沉淀法合成磁性海泡石,通过静态吸附实验研究磁性海泡石对Cr(Ⅵ)的吸附特性及其动力学。结果表明,磁性海泡石对Cr(Ⅵ)的吸附在90 min内即可达到平衡;体系的初始pH是影响磁性海泡石吸附Cr(Ⅵ)性能的重要因素;当废水中Cr(Ⅵ)的初始浓度为50 mg/L时,磁性海泡石的适宜投加量为10 g/L;随反应温度的升高,磁性海泡石对Cr(Ⅵ)的吸附量增加;温度为25、35和45℃时,磁性海泡石对Cr(Ⅵ)的饱和吸附量分别为3.32、3.72、4.08 mg/g;吸附动力学曲线可以用拟二级反应动力学模型拟合;内扩散和液膜扩散联合控制Cr(Ⅵ)在磁性海泡石上的吸附过程,其中内扩散的控速作用大于液膜扩散。     

铁炭微电解法降解TAIC废水

TAIC（三烯丙基异氰脲酸酯）作为过氧化物交联或自由基反应交联的助交联剂被广泛应用。由于TAIC性质稳定难于生物降解,采用铁炭微电解法处理TAIC生产废水,并考察了铁炭比、进水pH值、反应时间对处理效果的影响,以及TAIC降解机理和反应动力学过程。结果表明,影响微电解工艺的因素主次关系为：pH>Fe/C质量比>反应时间;在最佳条件进水pH值为5,铁炭质量比为2：1,反应时间为135 min时,COD的去除率达到46%以上,TAIC的去除率达到48%以上。TAIC去除机理研究表明,微电解对TAIC废水的作用主要通过·H的还原和铁离子的絮凝作用,其中·H的还原作用是TAIC降解的主要原因。反应动力学分析表明,铁炭微电解法处理TAIC的降解过程基本符合二级反应动力学规律,通过建立模型并拟合出了TAIC降解的二级反应动力学方程。     

煤炭企业发展低碳经济的动力机制

将影响煤炭企业发展低碳经济的动力因素分为四大类,包括4个拉力因素、1个支撑因素、2个压力因素和4个推动力因素。设计了煤炭企业发展低碳经济的动力机制模型,在分析各个动力因素的基础上,构建了煤炭企业发展低碳经济的拉力机制模型、支撑机制模型、压力机制模型和推动力机制模型。     

牛粪堆肥升温菌剂的筛选及其作用机制

以糖、淀粉、蛋白质、纤维素培养基及菌株增殖倍数、菌株性能等为筛选方法,从牛粪低温堆肥中筛选不同原料重要功能菌并组成功能菌剂;以不同类别原料菌及单菌株发酵实验对升温机制进行研究。结果表明,芽孢杆菌、假单胞菌、纤维单胞菌及小孢霉菌等为重要功能菌;菌剂起温快,升温效果好,48 h堆体即由低温进入中温,5 d达到高温,腐熟时间可缩短至约17~18 d;糖功能菌升温效果最为显著,淀粉及蛋白质功能菌次之,纤维素功能菌升温能力较弱;菌株利用各种原料能力越强,增殖速度越快,对升温作用越大。各菌株充分利用基质各成分,紧密协同和促进,是低温堆体发酵升温的主要作用机制。     

Modeling the Effects of Potential Salinity Shifts on the Recovery of Striped Bass in the Savannah River Estuary,Georgia–South Carolina,United States

Increased salinity in spawning and nursery grounds in the Savannah River estuary was cited as the primary cause of a 97% decrease in adult striped bass (Morone saxatilis) and a concomitant 96% decrease in striped bass egg production. Restoration efforts focused on environmental remediation and stock enhancement have resulted in restored salinity patterns and increased egg and adult abundances. However, future water needs or harbor development may preclude further recovery by reducing freshwater inflow or increasing salinity intrusion. To assess the effect of potential changes in the salinity regime, we developed models relating discharge, tidal phase, and salinity to striped bass egg and early larval survival and re-cast these in a quantitative Bayesian belief network. The model indicated that a small upstream shift (≤1.67 km) in the salinity regime would have the least impact on striped bass early life history survival, whereas shifts >1.67 km would have progressively larger impacts, with a 8.33-km shift potentially reducing our estimated survival probability by >28%. Such an impact could have cumulative and long-term detrimental effects on the recovery of the Savannah River striped bass population. The available salinity data were collected during average and low flows, so our model represents some typical and some extreme conditions during a striped bass spawning season. Our model is a relatively simplistic, “first-order” attempt at evaluating potential effects of changes in the Savannah River estuarine salinity regime and points to areas of concern and potential future research.     

20^#钢板镀铬在海洋环境条件下的腐蚀行为分析

本文根据20^#钢板镀铬材料在我国海洋环境的暴露结果,对20^#钢板镀铬材料在我国海洋环境条件下的腐蚀速度及腐蚀原因进行分析。