除湿机冷凝水中亚硝酸盐的浓度与大气环境质量的关系探讨

探讨了家用除湿机作为空气水溶性物质采集器的可行性。通过离子色谱仪对冷凝水离子成分的分析,并与空气总悬浮微粒(TSP)可溶性化学成分的对比,发现水汽中大部分阴阳离子的含量只比TSP低1个数量级。但TSP中一般检测不出亚硝酸根,而在水汽中则可检测出亚硝酸根离子,且水汽中亚硝酸根离子的浓度与取样位置的大气环境质量有关。     

Beryllium Concentrations in Ambient Air and Its Source Identification

Beryllium concentrations in atmospheric particulate and soil samples in and around a Beryllium Processing Facility (BPF) have been measured. The mean air concentration level of beryllium in and around the fence line of the BPF is 0.48 ± 0.43 ng m^-3 (n = 397) and is mostly influenced by diurnaland seasonal changes. The observed air concentration levelswere well below the prescribed ambient air quality (AAQ)standard of 10 ng m^-3. The soil concentration levels ofberyllium in the study area were found to be in the range of 1.42–2.75 g g^-1. The mass median aerodynamic diameter (MMAD)of beryllium aerosols in ambient air was found to be 6.9 m.Source identification using the Enrichment Factor (EF) approachindicates soil as the predominant contributory source for air concentrations at the site.     

使用ACCU单元采集空气中的颗粒物

使用由美国R＆P公司生产的Automatic Cartidge Collection Unit,即自动滤膜采集单元,简称ACCU单元,可进行设定条件下(如风向、时间、浓度等)的颗粒物采样,并对颗粒物质量浓度和有关元素的浓度进行分析,它不但能测定颗粒物和有关元素的浓度水平,还能判定有关条件下的浓度分布.使用实践证明,该单元可为环境监测和治理提供有力和方便的手段.     

Reduction of sampling and analytical errors for electron microscopic analysis of atmospheric aerosols

Electron microscopy-energy dispersive spectroscopy (EM/EDS) can be used to determine the elemental composition of individual particles. However, the accuracy with which atmospheric particle compositions can be quantitatively determined is not well understood. In this work we explore sources of sampling and analytical bias and methods of reducing bias. Sulfuric acid [H₂SO₄] and ammonium sulfate [(NH₄)₂SO₄] particles were collected on beryllium, silicon, and carbon substrates with similar deposition densities. While [(NH₄)₂SO₄] particles were observed on all substrates, [H₂SO₄] and ammonia-treated [H₂SO₄] particles could not be found on beryllium substrates. Interactions between the substrate and sulfuric acid particles are implicated. When measured with EM/EDS, [H₂SO₄] particles exposed to ammonia overnight were found having lower beam damage rates (0.000 ± 0.002 fraction s⁻¹) than those without any treatment (0.023 ± 0.006 fraction s⁻¹) For laboratory-generated [C₁₀H₆(SO₃Na)₂] particles, the composition determined using the experimental k-factors evaluated from independent particle standards of similar composition and size shows an error less than 20% for all constituents, while greater than 78% errors were found when k-factors were calculated from the theory. This study suggests (1) that sulfate beam damage can be reduced by exposure of atmospheric particle samples to ammonia before analysis, (2) that beryllium is not a suitable substrate for atmospheric particle analysis, and (3) calibration (k-factor determination) using particle standards of similar size and composition to particles present in the atmosphere shows promise as a way of improving the accuracy of quantitative EM analysis.     

玉米粒为载体的流化床生物膜反应器处理印染废水

以废弃玉米粒为载体,在生物膜流化床试验装置上进行印染废水处理试验研究。结果表明,与炉渣载体比较成膜时间缩短2 d;形成的生物膜生长到载体内部,结合牢固;曝气量(20~30 L/h.L)受流化状况控制,比非生物质载体时略大,玉米粒含量为2~4 g/L时,COD、色度和浊度的去除率分别为72%、85%和86%。     

湍流环形通道热泳脱除可吸入颗粒物技术研究

湍流中PM2．5粒子的热泳沉积是国际上研究热门课题。但目前单纯热泳沉积效率也不过20％左右。依据热泳基本原理，设计了一种新型湍流方环形双壁冷却式通道。计算表明，该类型通道比一般单管通道有着较高的可吸入颗粒物脱除效率。同时，利用湍流的沉积效率，加上热泳沉积效率。可以达到较高的总泳沉积效率。通过结构设计，可以提高可吸入颗粒物的脱除效率，是值得进一步探索的新路子。     

氯代十六烷基吡啶缔合微粒光度法测定二氧化氯

在pH3.49的NaAC-HCl介质中,ClO2与过量的KI反应生成I3-,I3-在350nm处有一吸收峰;当阳离子表面活性剂(CS)氯代十六烷基吡啶(CPCM)等存在时,形成淡黄色的较稳定的缔合微粒(CPCM-I3)n,在354nm处产生一个吸收峰,在470nm和520nm处产生2个共振散射峰。ClO2浓度C在0.0149～1.524mg/L范围内符合朗伯比耳定律,回归方程为△A=0.1136C+0.0001,相关系数R为0.9988,检测限为0.007mg/L。据此,建立了一种痕量ClO2光度分析新方法,用于样品分析,结果令人满意。     

溶胶-凝胶工艺制备掺铅TiO_2纳米薄膜及其光催化性能的研究

通过ｓｏｌ－ｇｅｌ工艺在玻璃表面制得了均匀透明的掺铅和未掺铅ＴｉＯ２纳米薄膜；在宏观上，膜层表面光滑平整；在微观上，ＴｉＯ２薄膜由ＴｉＯ２球形颗粒组成，其颗粒大小在５０～１５０ｎｍ范围内。掺铅ＴｉＯ２镀膜玻璃在紫外光附近的透光率明显小于未掺铅ＴｉＯ２镀膜玻璃的透光率，这说明掺铅ＴｉＯ２镀膜玻璃对紫外光具有明显的吸收。敌敌畏水溶液的光摧化降解实验表明，掺铅ＴｉＯ２镀膜玻璃对有机磷农药的光解率明显高于未掺铅ＴｉＯ２镀膜玻璃的光解率。这为进一步提高ＴｉＯ２的光催化效率开辟了新的途径。     

微粒羽流中粉尘的实验研究

通过实验观察和实验结果分析，研究了自由下落羽流产生的粉尘与物料本身的物理参数和工作参数的变化关系，并对实际生产操作过程中如何减少粉尘的产生提供了参考建议。     

利用静电旋风除尘器捕集亚微米粒子的研究

利用高场强静电旋风除尘器捕集柴油机排放的亚微米粒子,通过实验证实了,静电旋风除尘器可以有效捕集亚微米粒子。提出了对于该静电旋风除尘器,粒子的有效驱进速度与进口风速的关系式,这对于发展捕集亚微米粒子的静电旋风除尘器具有一定的参考价值。为控制柴油机的颗粒物排放提供了一个新的思路。