The collection of PM10 for toxicological investigation: comparisons between different collecting devices

A positive correlation has been established between increased levels of airborne particulate pollution and adverse health effects, the toxicological mechanisms of which are poorly understood. For toxicologists to unambiguously determine thesemechanisms, truly representative samples of ambient PM₁₀ are required. This presents problems, as PM₁₀ collecting equipment commonly employed, such as the Tapered Element Oscillating Microbalance (TEOM®), heat the inflow toexclude moisture or use fibrous filters, resulting in a PM₁₀sample that may have undergone significant chemical change on thefilter surface or is contaminated by filter fibres. Other systems(i.e. Negretti and Partisol) can successfully collect PM₁₀ without chemical alteration or filter contamination. Comparativecollections from Port Talbot, S. Wales suggest that TEOMs and Negretti/Partisol systems collect different PM₁₀'s; the principle difference arising from the TEOM's heating chamber, which precipitates water-soluble ions and volatilises some organic components. This results in both the mass and compositionof the PM₁₀'s being altered. Particle size distributionsfor Negretti and Partisol collections highlighted differences mainly attributed to different flow rates. The results of thiswork demonstrate that simple correlations between PM₁₀ massand adverse health effects are problematic. Furthermore, elucidation of the complex fractionation and chemical changes indifferent collectors is necessary.     

上海磁悬浮快速列车环境振动影响探讨

通过对磁悬浮快速列车沿线两侧区域振动监测,得出振动级VLzmax与列车速度有较好的相关性,实测得出了振动随车速变化的衰减系数。同时给出了振动随离轨道距离变化的衰减方程,参照现有环境振动国家标准,给出了不同车速下磁悬浮轨道两侧区域的振动达标距离。     

离子色谱法测定空气中乙酸和溴化氢

用同一吸收液采集、离子色谱法测定空气中的乙酸和溴化氢,采样体积为60 L时,乙酸和溴化氢的检出限分别为0.03 mg/m3和0.11 mg/m3,相对标准偏差分别为1.9%和1.7%,实际样品的加标回收率分别为90.1%～102%和97.6%～100%.     

Occurrence and congeners specific of poiychlorinated biphenyls in agricultural soils from Southern Jiangsu, China

A total of 198 agricultural soil samples were collected from Zhangjiagang and Changshu in Southern Jiangsu for analysis of 13 polychlorinated biphenyls (PCBs) in order to assess the levels of pollution, sources, area distribution, and potential risk for the environment. All methods were rigorously tested and an adequate quality control was ensured. Only one site had no PCBs residues, and the highest total PCBs concentration in the surface soils was 32.83 ng/g. The average concentration in all the soil samples was 4.13 ng/g, signaling low-level pollution. Tetra-, penta-, and hexa-chlorinated biphenyls were dominant species in soil samples, accounting for more than 75% ofΣPCBs in the soil samples. PCB118 was the most abundant congener in all the samples. The PCB118 was about 20% ofΣPCBs. The soil organic matter content showed only a weak correlation with the levels of all PCB congeners, in which a better correlation was noted for the more volatile lighter PCB congeners than for the heavier homologues. To a certain extent, the sources and land use seemed to influence the levels of PCBs.     

Effects of the surface chemistry of macroreticular adsorbents on the adsorption of 1-naphthol/1-naphthylamine mixtures from water

The adsorption behaviors of 1-naphthol, 1-naphthylamine and l-naphthol/l-naphthylamine mixtures in water over two macroreticular adsorbents were investigated in single or binary batch systems at 293 K, 303 K and 313 K respectively. All the adsorption isotherms in the studied systems can be adequately fitted by Langmuir model. In the case of aminated macroreticular adsorbent NDA103, 1-naphthol is adsorbed to a larger extent than 1-naphthylamine; while, the opposite trend is found for nonpolar macroreticular adsorbent NDA100. It is noteworthy that at higher temperature（303 K and 313 K）, the total uptake amounts of 1-naphthol and 1-naphthylamine in all binary-component systems are obvious larger than the pure uptake amounts in single-component systems, which is presumably due to the cooperative effect primarily arisen from the hydrogen-bonding interaction between the loaded 1-naphthol and 1-naphthylamine molecules. The simultaneous adsorption systems were confirmed to be helpful to the selective adsorption towards 1-naphthol according to the larger selective index.     

广州市32种水产品的Se含量特征分析

通过酸消解,原子荧光-氢化物发生法测定了广州市部分市售水产品中Se的含量,由标准物质(GBW 08551猪肝)和回收率控制检测质量.结果表明,不同水产品中Se含量有较大差异,含量范围为(34.-1117.)×10-9,平均含量为(345.±149.)×10-9,不同类型水产品中Se含量变化特征是:甲壳类(544.±107.)×10-9＞海水鱼类(392.±86.)×10-9＞软体类(244.±89.)×10-9＞淡水鱼类(238.±97.)×10-9.     

三种填料对生活污水中氨氮的去除效果

研究了沙子、砾石、珍珠岩三种填料对生活污水中氨氮（NH3-N）的去除效果。结果表明：沙子对污水中NH3-N的去除效果最好，珍珠岩次之，砾石的去除效果最差。三种填料对生活污水中NH3-N的平均去除率分别为59．6％、20．4％和13．3％。     

模拟在役井注减氧空气对1Cr-L80井筒管材防腐研究

目的在充分调研陆上及渤海周边相似油气田注气开发井筒腐蚀情况的基础上,明确注减氧空气开发井对井筒全寿命周期管材腐蚀速率大小。方法系统性开展注气井不同含氧量条件下的动态腐蚀实验研究,并对生产井动态腐蚀进行评价,深入分析减氧空气对油井管腐蚀行为,分类分层次分析归纳注减氧空气工况管柱腐蚀特性、腐蚀速率影响因素以及管柱腐蚀风险。结果得出在注气井井口、井中、井底工况,不同氧气浓度下,1Cr-L80管材在注气井井口、井中、井底的腐蚀关系曲线。在含氧量为5%(质量分数)的注气井井口、井中、井底,1Cr-L80的腐蚀速度分别为0.345、0.2147、0.1158mm/a;在含氧量为21%的注气井井口、井中、井底,1Cr-L80的腐蚀速率分别为0.7399、1.2854、2.4506 mm/a。结论1Cr-L80材质腐蚀速率均保持在较高水平,老井直接注入空气会存在高腐蚀风险。     

PHBV表面疏水改性用作吸油材料的研究

利用多种表面改性剂对生物可降解材料PHBV进行了表面改性实验研究，测定了不同改性剂改性后PHBV的吸油率以及温度对其吸油效果的影响，并探讨了改性机理，研究结果表明：不同改性剂对PHBV的改性效果有所差异，从疏水和吸油的共同效果来看，最佳疏水改性剂为添加量5％时的硅油，温度对未改性PHBV和改性PHBV的吸油率及吸油速度均有影响。     

云南白秧坪铜银矿床Cu、Ag迁移形式探讨

在野外地质研究的基础上,采用地球化学热力学方法研究了Cu、Ag的迁移形式。研究结果表明,铜在热液中主要以CuCl42-、Cu(H2O)42+、Cu(S2O3)46-、CuS46-、Cu(HS)42-、Cu(SbS3)410-形式迁移;银在热液中主要以AgCl2-、Ag(S2O3)23-、Ag(HS)2-、AgS23-、Ag(SbS3)25-形式迁移。铜银矿床是在含矿热液物理化学条件发生改变的情况下铜银化合物发生解析作用而成。