装潢居室空气中甲醛采样方法改进

对空气中甲醛测定的采样方法进行了探讨 ,分别用水和稀硫酸作吸收液对空气甲醛进行采样研究。结果表明 ,用 0 .0 0 5mol LH2 SO4 作吸收液的采样方法 ,可有效、稳定地延长样品的保存时间 ,且又符合方法灵敏度和精密度的要求。     

常熟氟化学工业园水环境和生物样品中全氟化合物的分布

采用Oasis-WAX-SPE柱富集,高效液相色谱/电喷雾负离子源串联质谱(HPLC/negative ESI/MS/MS)对常熟氟化学工业园区地表河水样品和水生动物样品(乙腈萃取物)中的全氟及多氟化合物(PFASs)进行了测定,分别检测出8种和14种PFASs.园区河水中总PFASs浓度范围为91.0—9374.9 ng.L-1,为国内已有报道中最高;PFOA和PFPrA是河水样品中含量最高的两种PFASs,且在不同水样中均可占到总PFASs的73%以上,未检出PFOS;生物样品中总PFASs浓度范围为12.93—394.77 ng.g-1ww(湿重),PFOA、PFOS和PFPrA为主要PFASs;与园区所在城市的鱼类等样品相比较,采自氟化学工业园区的鱼类体内富集了更多的PFAS.研究结果表明,常熟氟化学工业园区地表水环境PFOA和PFPrA污染较重,为目前国内最高水平;在园区河水和生物体内检测出高浓度的PFPrA,说明氟化学工业园区内部分工厂可能已使用短链氟化物替代PFOA和PFOS,在今后的研究中对PFPrA等短链全氟化合物的监测应给予更多关注.     

黏结剂对污泥基颗粒炭性能的影响

以城市污水处理厂剩余污泥为原料,可溶淀粉、羧甲基纤维素、硅酸钠和硫酸钙为黏结剂,采用两步炭化法制备污泥基颗粒炭,探讨了黏结剂种类对样品性能的影响.结果显示:可溶淀粉样品(SSGAC-T)具有最大的比表面积和孔容,SSGAC-T、羧甲基纤维素样品(SSGAC-C)和硅酸钠样品(SSGAC-Si)含有丰富的微孔和中孔,硫酸钙样品(SSGAC-S)为典型的中孔吸附剂;样品的抗压强度均随浸泡时间的延长而降低,但SSGAC-S的抗压强度下降程度最小;4种黏结剂都使样品表面生成新的官能团,且样品的表面均呈酸性,它们的pHPZC分别为6.37、6.16、5.85和5.53;相同条件下,SSGAC-S对亚甲基蓝的饱和吸附量最高,为71.94mg/g;根据对污泥炭的表征,初步推测硅酸钠和硫酸钙能与碳发生化学反应.     

Best linear unbiased estimators for the simple linear regression model using ranked set sampling

When sample observations are expensive or difficult to obtain, ranked set sampling is known to be an efficient method for estimating the population mean, and in particular to improve on the sample mean estimator. Using best linear unbiased estimators, this paper considers the simple linear regression model with replicated observations. Use of a form of ranked set sampling is shown to be markedly more efficient for normal data when compared with the traditional simple linear regression estimators.     

PCDDs and PCDFs in food samples from Catalonia, Spain. An assessment of dietary intake

Food samples from local markets and supermarkets of Tarragona (Catalonia, Spain) were analyzed for PCDD/F concentrations. On lipid basis, PCDD/F levels in meat, fish, eggs, and fats and oils were similar or lower than those found in other countries. By contrast, in general terms PCDD/F levels in milk, vegetables, and cereals showed higher levels than those previously reported. The total dietary PCDD/F intake by the population of Tarragona was estimated to be 210 pg I-TEQ/day. This value is higher than the dietary intake of PCDD/Fs found in a number of surveys from other countries. However, when total dietary intake of PCDD/Fs was calculated including only fish and seafood, meat, milk and dairy products, eggs, and fats and oils, a dietary intake of PCDD/Fs of 117 pg I-TEQ/day was obtained. This intake is in the same range than that reported for different regions and countries. The results of the present study show that food groups such as vegetables, fruits, and cereals should not be excluded to estimate the total dietary intake of PCDD/Fs by general populations, especially in those countries and/or regions in which their consumptions are notable.     

膜萃取-微扑集/气相色谱-质谱测定小体积水样中痕量苯系物的方法

用膜萃取－微脯集／气相色谱－质谱分析方法,分别测定环境地表水,工厂排污水,饮用水和汽油等样品中痕量苯,甲苯和甲苯等有机污染物。结果表明,膜萃取,微捕集回收率为８９％－９９％,相对标准偏差为１．１６－３．６０％。     

Determination of total content and isotopic compositions of plutonium and uranium in environmental samples for safeguards purposes by ICP-QMS

The aim of this work was to determine the concentrations and isotopic compositions of plutonium and uranium in environmental samples for safeguards purposes. An analytical method was developed with a plutonium and uranium separation procedure based on extraction chromatography (using 2 mL TEVA and UTEVA columns) and detection with a quadrupole ICP-MS applying an ultra-sonic nebulizer coupled with a membrane desolvation system. Starting from blank swipes, the background equivalent concentration (BEC) was 8 fg for ²³⁹Pu and 1 ng ²³⁸U. The method was successfully applied to certified reference materials as well as to round robin samples obtained in the framework of the inter-laboratory exercise program, promoted by the Brazilian–Argentine Agency for Accounting and Control of Nuclear Materials (ABACC), together with the US Department of Energy (USDOE). After the introduction of an additional ion-exchange separation step, the methodology was applied to the IAEA-384 sediment reference sample with precise and accurate total plutonium and uranium, ²⁴⁰Pu/²³⁹Pu, ²⁴¹Pu/²³⁹Pu, ²³⁴U/²³⁸U and ²³⁵U/²³⁸U atomic ratio results.     

烟尘样品分析的实验室质量控制

通过对烟尘样品的试验与比较研究,提出了烟尘样品分析的实验室质量控制要求和方法     

环境样品中DNA提取方法的研究进展

利用微生物降解污染物是废水处理中的常用方法,研究废水处理工艺中微生物的多样性和动态性对于优化废水处理工艺的性能、提高其处理效率具有重要的指导意义.分子生物学方法是研究微生物多样性和动态性的有效方法.由于大多数分子生物学方法都是以提取研究对象的基因组DNA为前提,因此建立一种高效的环境样品DNA的提取方法具有重要作用.综述了从环境样品中提取DNA的主要方法及其研究进展,并提出了一种有效的从活性污泥中提取DNA的具体方法.     

发光细菌法监测河流水质状况

运用发光细菌法对淮阴市河流水样的毒性进行监测，并以毒性较为稳定的HgCl2作参比毒物，使此法所测得的毒性 定量化。据水质毒性分级标准，对水样毒性测定结果进行评价，同时参照水质的理化因子，可以看出，该方法测出的水质毒性能够更好地反映出水质的污染状况。