Chemical characterization and source apportionment of atmospheric submicron particles on the western coast of Taiwan Strait, China

Taiwan Strait is a special channel for subtropical East Asian Monsoon and its western coast is an important economic zone in China. In this study, a suburban site in the city of Xiamen on the western coast of Taiwan Strait was selected for fine aerosol study to improve the understanding of air pollution sources in this region. An Aerodyne high-resolution time-of-flight aerosol mass spectrometer(HR-To F-AMS) and an Aethalometer were deployed to measure fine aerosol composition with a time resolution of 5 min from May 1to 18, 2015. The average mass concentration of PM1 was 46.2 ± 26.3 μg/m~3 for the entire campaign. Organics(28.3%), sulfate(24.9%), and nitrate(20.6%) were the major components in the fine particles, followed by ammonium, black carbon(BC), and chloride. Evolution of nitrate concentration and size distribution indicated that local NOx emissions played a key role in high fine particle pollution in Xiamen. In addition, organic nitrate was found to account for 9.0%–13.8% of the total measured nitrate. Positive Matrix Factorization(PMF)conducted with high-resolution organic mass spectra dataset differentiated the organic aerosol into three components, including a hydrocarbon-like organic aerosol(HOA) and two oxygenated organic aerosols(SV-OOA and LV-OOA), which on average accounted for 27.6%,28.8%, and 43.6% of the total organic mass, respectively. The relationship between the mass concentration of submicron particle species and wind further confirmed that all major fine particle species were influenced by both strong local emissions in the southeastern area of Xiamen and regional transport through the Taiwan Strait.     

KMnO4-PAC对高原喀斯特湖库DOM的DBPsFP控制

以云贵高原典型喀斯特湖库红枫湖取水口溶解性有机质（DOM）为研究对象,调查不同组合方式下高锰酸钾-聚合氯化铝（KMnO₄-PAC）对消毒副产物的生成潜能（DBPsFP）变化和平均组成分布,并通过红外光谱（FTIR）和三维荧光光谱（3D-EEM）对部分样品进行化学表征,推断其影响机制.结果表明：在0.1,0.2,0.4mg/L KMnO₄投加量下,DBPsFP降低17.5~73%,DOM的卤代活性化学结构和官能团部分被有效钝化;PAC的网捕和卷扫效应使DBPsFP进一步减少27.9~86.1%,组合工艺对DBPs的生成潜能影响大小为：三卤甲烷（THM₄） > 卤乙酸（HAA₉） > 卤乙腈（HAN₄）/卤代酮（HK₂）/三氯硝基甲烷（TCNM）.FTIR的结果表明预氧化后3300cm^-1处的透过率降低,指纹区1000~1300cm^-1处的峰频提升,表明分子中的O-H、COOH和C-O官能团增加,共轭不饱和结构在KMnO₄作用下部分消失.3D-EEM验证了外源有机物（腐殖酸）在DOM中占比随KMnO₄浓度梯度升高而下降,同时类蛋白结构的吸收峰强度增加,说明最终DBPs贡献可能源于DOM中剩余的小分子类蛋白（氨基酸）.     

秋冬交替季节白洋淀沉积物有机质特性研究

为了研究白洋淀沉积物中有机质释放对秋冬交替季节淀区水环境的影响.将白洋淀分为自然保护区、旅游区、村落密集区、淀中村区和出淀口区五部分,在20个代表性采样点采集沉积物样品,采用光谱学方法表征样品中有机质特性,并研究氮、磷的溶解释放特征.结果表明:①在自然保护区、淀中村区和出淀口区,沉积物中有机质的腐殖化和芳香化程度较高,主要为陆源可见光类腐殖酸组分（C1）、海源可见光类腐殖酸组分（C3）和紫外光类腐殖酸组分（C4）;而在旅游区和村落密集区,有机质的腐殖化和芳香化程度较低,主要为类色氨酸组分（C2）,表明这些区域受人为活动影响大.②紫外吸收光谱和荧光光谱参数具有很好的相关性,可用于表征沉积物中有机质特征;类色氨酸组分的荧光强度与沉积物中w（TN）和w（TP）具有良好的正相关关系,显示出同源性特征.③与以类腐殖酸为主要成分的沉积物样品相比,氮、磷更易从以类蛋白为主要成分的沉积物中释放.研究显示,秋冬交替季节白洋淀沉积物中有机质以类蛋白和类腐殖酸为主,且类蛋白具有促进共存氮、磷溶解释放的作用.      

外绝缘用液体硅橡胶老化现象的微观表征

本文针对近年来出现在一些变电站SF6电压、电流互感器的液体硅橡胶绝缘护套出现龟裂老化这一现象,对发生老化的硅橡胶材料进行了性能测试和试验,并利用红外光谱分析、XPS分析、热失重等手段分析了其微观结构和物质组成的变化。研究发现老化后的液体硅橡胶中Si-C、Si-O官能团和Si、C、O元素的相对含量发生了变化,且随着老化程度的增加呈现出较为明显的规律,老化越严重,Si-C键含量越少,C元素的含量越少,O元素含量越多。本文认为,用官能团含量、元素相对含量可以准确地表征液体硅橡胶材料的老化程度。通过对不同老化程度的液体硅橡胶进行的憎水性、耐漏电起痕性能的试验也证实了本文的观点。     

商业SCR烟气脱硝催化剂钙中毒研究

使用2种不同浓度的前驱体溶液(Ca(NO3)2和Ca(CH3COO)2溶液)浸渍新鲜商业SCR(selective catalytic reduction)烟气脱硝催化剂,并对浸渍中毒后催化剂的性能进行了研究。实验结果表明,物理中毒在本研究中占主导位置,化学中毒并不明显。采用离子色谱、氮气吸附-脱附分析、红外光谱分析、X射线衍射分析、扫面电镜分析等多种表征技术对中毒后催化剂进行了表征。结果表明,中毒后催化剂孔结构性质发生了变化,特别是Ca(CH3COO)2溶液浸渍催化剂,内部孔道堵塞较为严重。X射线衍射分析和扫描电镜分析也从另一方面说明了CaCO3的出现及积累导致催化剂脱硝效率降低。此外,催化剂红外光谱分析从表面活性位的角度说明了本研究催化剂化学中毒现象并不明显。     

基于ASM2的快速易生物降解COD组分表征方法构建

基于活性污泥2号模型（ASM2）对快速易生物降解组分（SS）进一步划分为可发酵的易生物降解有机物（SF）和发酵产物（SA）,本研究提出了一套科学的表征方法。该方法涉及SS与XS（慢速可生物降解组分）的好氧呼吸测量同时表征、SA组分的离子色谱测定以及物料衡算。应用这套方法对重庆市某2个城市污水厂隔栅井出水水样平行进行了4组实验,各种组分测量值序列的CV值在2.09%～6.18%之间。     

优选粉煤灰制备人工合成沸石及去除氨氮研究

7种粉煤灰样品的物理化学性质,如元素组成、结晶相组成、比表面积、灼失量、阳离子交换容量和pH得到表征。采用熔融法提取硅铝效率作为粉煤灰原料优选的依据,并通过L9（34）正交实验研究氢氧化钠投加量、熔融温度、氢氧化钠提取液浓度和体积对于硅铝提取效果的影响。结果表明,湿式除尘技术收集的低品位粉煤灰比电除尘技术所收集粉煤灰更...     

γ-Al_2O_3负载Ni、Fe催化剂同时脱硫脱硝

采用浸渍法制备了不同负载量的Ni(x)Fe(y)/γ-AL2O3催化剂,通过XRD、H2-TPR、BET和SEM对催化剂进行表征,使用微型催化反应装置考察催化剂在以CO作为还原气时,同时脱硫脱硝的催化活性。结果表明,Ni O和Fe2O3做为活性组分可以很好地分散在γ-Al2O3载体上,并且不破坏其结构;Ni(8)Fe(2)/γ-Al2O3催化剂有最佳的脱硫脱硝活性,脱硫率达到96.55%,脱硝率达到97.92%。     

微生物絮凝剂MBF TS-1的表征

对筛选的一株絮凝剂产生菌Bacillus TS-1所产絮凝剂MBF TS-1采用UV- vis吸收光谱、FT-IR光谱、糖类颜色反应、动物急性毒性实验等进行了化学组成分析、表征和理化性质检测.结果证实,该絮凝剂为安全无毒、分子量为105-106的弱酸性多糖类物质,属环境友好型微生物絮凝剂.     

A multiscale hierarchical Markov transition matrix model for generating and analyzing thematic raster maps

A model is described for generating hierarchically scaled spatial pattern as represented in a thematic raster map. The model involves a series of Markov transition matrices, one for each level in the scaling hierarchy. In full generality, the model allows the transition matrices to be different at each level, potentially making available a large number of parameters for landscape characterization. The model is self-similar when the transition matrices are all equal. A method is presented for fitting the model to data that take the form of a single-resolution thematic raster map. Explicit analytic solutions are obtained for the fitted parameters. The fitting method is based on a relationship between the hierarchical transitions in the model and spatial transitions at varying distance scales in the data map, a categorical analogy of the geostatistical variogram.