成组切边模的设计

提出了成组切边模设计的观点,并结合为企业实施成组切边模的实践,介绍了成组切边模设计的步骤、方法和成组切边模标准。     

Deep learning architecture for air quality predictions

With the rapid development of urbanization and industrialization, many developing countries are suffering from heavy air pollution. Governments and citizens have expressed increasing concern regarding air pollution because it affects human health and sustainable development worldwide. Current air quality prediction methods mainly use shallow models; however, these methods produce unsatisfactory results, which inspired us to investigate methods of predicting air quality based on deep architecture models. In this paper, a novel spatiotemporal deep learning (STDL)-based air quality prediction method that inherently considers spatial and temporal correlations is proposed. A stacked autoencoder (SAE) model is used to extract inherent air quality features, and it is trained in a greedy layer-wise manner. Compared with traditional time series prediction models, our model can predict the air quality of all stations simultaneously and shows the temporal stability in all seasons. Moreover, a comparison with the spatiotemporal artificial neural network (STANN), auto regression moving average (ARMA), and support vector regression (SVR) models demonstrates that the proposed method of performing air quality predictions has a superior performance.     

人工湿地与土壤净化槽处理农村生活污水的对比

针对我国生活污水处理现状及要求,对比研究了普遍推广的人工湿地技术与新兴的土壤净化槽技术,发现在进水水质、环境条件均相同的情况下,上行流人工湿地处理效果优于下行流人工湿地;基质按照不同需氧层铺设不同粒径填料的土壤净化槽处理效果优于基质直接分层铺设填料的土壤净化槽;土壤净化槽和人工湿地出水水质都很好,出水CODCr、TN、TP、氨氮分别达到了二级、一级A、一级B、一级A标准;土壤净化槽装置占地面积小,为人工湿地的2/3.土壤净化槽技术是适合我国国情的有发展前景的生活污水处理技术.     

The effect of preparation conditions of Pt/Al2O3 on its catalytic performance for the H2-SCR in the presence of oxygen

Selective catalytic reduction of NO _x by H₂ in the presence of oxygen has been investigated over Pt/ Al₂O₃ catalysts pre-treated under different conditions. Catalyst preparation conditions exert significant influence on the catalytic performance, and the catalyst pre-treated by H₂ or H₂ then followed by O₂ is much more active than that pre-treated by air. The higher surface area and the presence of metallic Pt over Pt/Al₂O₃ pre-treated by H₂ or pretreated by H₂ then followed by O₂ can contribute to the formation of NO₂, which then promotes the reaction to proceed at low temperatures.     

Efficient photoelectrochemical oxidation of rhodamine B on metal electrodes without photocatalyst or supporting electrolyte

We designed photoelectrochemical cells to achieve efficient oxidation of rhodamine B (RhB) without the need for photocatalyst or supporting electrolyte. RhB, the metal anode/cathode, and O₂ formed an energy-relay structure, enabling the efficient formation of O ₂ ^– species under ultraviolet illumination. In a single-compartment cell (S cell) containing a titanium (Ti) anode, Ti cathode, and 10 mg·mL^–1 RhB in water, the zero-order rate constant of the photoelectrochemical oxidation (k_PEC) of RhB was 0.049 mg·L^–1·min^–1, while those of the photochemical and electrochemical oxidations of RhB were nearly zero. k_PEC remained almost the same when 0.5 mol·L^–1 Na₂SO₄ was included in the reactive solution, regardless of the increase in the photocurrent of the S cell. The k_PEC of the illuminated anode compartment in the two-compartment cell, including a Ti anode, Ti cathode, and 10 mg·mL^–1 RhB in water, was higher than that of the S cell. These results support a simple, eco-friendly, and energysaving method to realize the efficient degradation of RhB.

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沼泽红假单胞菌W12对活性黑5的厌氧脱色和降解作用

从处理印染废水的厌氧移动床生物膜反应器（moving bed biofilm reactor, MBBR）中分离到一株具有高效脱色活性的沼泽红假单胞菌W12。经实验确定W12对活性黑5（reactive black 5,RB5）脱色的适宜条件为：pH＜10;有光照;谷氨酸盐或乳酸盐作为碳源,当乳酸钠为碳源时浓度应＞500 mg/L;盐度不超过5％;RB5浓度不大于700 mg/L。紫外可见光谱扫描结果表明,RB5的脱色和降解过程生成芳香胺类化合物,这些中间产物可进一步降解。此外发现,RB5诱导生成的胞外代谢物能提高W12的脱色活性。     

优势菌的筛选及其强化活性污泥好氧反硝化的研究

利用含活性污泥提取物的贫培养基筛选SBR系统中的好氧异养优势菌。结合自然温度（15～20℃）、延长培养时间等条件来提高菌群的可培养性。从SBR活性污泥系统中分离出5种细菌。4株去除COD优势菌,1株异养硝化细菌,能在好氧条件下实现对总氮的去除。反应池底采用边缘对称曝气,反应池内细菌在时间顺序和空间位置上循环经历好氧过程及微氧过程。将PVA铝盐法固定的细菌对反应器进行生物强化。结果显示,在好氧工艺的条件下,投加优势菌群后,与未加优势菌群的反应器相比,可以显著改善污泥的沉降性能,COD、NH₃-N和TN降解率显著提高,分别达到98%、97%和90%。生物强化作用明显,反应器内具有良好的好氧反硝化环境。     

好氧颗粒污泥降解甲基叔丁醚的实验研究

以絮状活性污泥为接种污泥,以甲基叔丁醚(MTBE)为唯一碳源,通过调控运行参数,在SBR反应器中可成功培养出降解MTBE的好氧颗粒污泥.成熟的好氧颗粒污泥平均粒径为202.7 μm,污泥容积指数(SVI)为75 mg/L,污泥混合液挥发性悬浮固体(MLVSS)为1 311 mg/L,污泥表面可观察到球菌、短杆菌和长杆菌等不同菌落.反应器进水MTBE高达650 mg/L时,出水可维持在10 mg/L以下,去除率达98%以上(其中挥发部分约占25%).变性梯度凝胶电泳(DGGE)指纹图表明,稳定阶段污泥内微生物种群丰富,且种类与数量基本保持稳定.     

邻苯二甲酸酯降解细菌的多样性、降解机理及环境应用

邻苯二甲酸酯(phthalic acid esters,PAEs)是一类对人体内分泌系统有干扰作用的持续性有机污染物(persistent organic pol utants,POPs)。PAEs在环境介质如水体、底泥和土壤中长期赋存会对生物体产生毒害效应,其分布广、浓度高和难降解等特点是限制有效环境治理的主要因素。作为环境的重要组成部分,微生物对污染物有很强的适应能力和高效的降解能力,这为PAEs的生物修复提供了可能。与物理化学修复法相比,微生物修复技术具有可控性强、修复面广和灵活性高等优势。本文综述了已报道的大部分PAEs降解细菌的种类及其代谢机制,并分析了其在PAEs污染水体和土壤修复中的应用现状与前景,以期为PAEs环境行为与生物修复研究提供参考。