超临界CO2流体萃取土壤中污染物的应用研究进展

CO2在超临界状态下具有许多独特的物理化学性质,作为一种“绿色”溶剂,它具有无毒、无污染、易获取等优点。近年来,有关超临界CO2流体热力学相行为和溶解度性质的研究引起人们广泛的关注,与之密切相关的超临界流体萃取技术已在许多领域得到重视和发展。根据近年国内外运用超临界CO2流体对土壤中多环芳烃、多氯联苯、重金属等污染物的萃取应用,分析了温度、压力、共溶剂等因素对萃取效果的影响,通过与其他土壤修复技术的比较,展望了超临界流体萃取技术应用于土壤修复领域的可行性和研究方向。     

萃取分离—石墨炉原子吸收光谱法测定铅锌矿中的铟

样品经硝酸、氢氟酸分解除硅,加热硫酸冒烟除尽硝酸、氢氟酸,利用铟与氢溴酸能生成稳定的络合物并被乙酸丁酯萃取的性质,将铟与其它干扰离子分离并富集.使用MOLAARM6（Thermo Electron Corporation）石墨炉原子吸收分光光度计,以钒为机体改进剂,测定铅锌矿中的铟.方法检出限为LD=0.012ug/ml.实验结果令人满意.     

戊基磷酸二戊酯萃取色层分离-电感耦合等离子体质谱法测定铀产品中9种杂质元素

铀产品中杂质元素的含量测定在核法证学溯源分析或燃料元件厂质量检验中具有重要应用价值,保证测量的准确度主要在于控制流程空白、提高杂质元素的回收率。本文建立了戊基磷酸二戊酯(UTEVA)树脂快速分离铀与杂质元素、电感耦合等离子体质谱法(ICP-MS)测定杂质元素含量的系统流程。结果表明,UTEVA树脂对铀的吸附能力强,铀样品取样量为16.43 mg时,全流程对铀的去污因子大于3×105,9种杂质元素(锰钼镍铜铬铝钛钒镉)的回收率为95.1%~105.1%,国家标准物质GBW04205中杂质元素的分析结果与参考值在不确定度(k=2)范围内一致。本工作建立的分离流程对铀的去污效果好,特别适用于样品量少的情况下铀中杂质元素的分析,为核法证分析最终的归因溯源或燃料质量检验提供了技术支持。     

Genetic study of Kelp “901” strain

Based on DNA extraction and optimization of random amplified reaction (RAPD) to the gametophytes and sporophytes of Kelp “901” strain, genetic study on variation was conducted to its parents and offsprings of F6, F7,Fs, and F9 generation. RAPD results have shown that among 30 selected primers for gametophytes, 297 loci ranging from 200 to 3 000 bp were obtained in the average of 9,9 loci for each primer, This indicated a high polymorphic rate with RAPD detection. UPGMA (unweighted pair-group method arithmetic average) analysis showed that each male and female gametophyte of a generation could be clustered into one pair separately. The genetic distances of the Kelp 901 generation were 0.321 2-0.476 7, and the maximum was between F7 and Fs (0.476 7). Identity analysis showed that F6 generation was more close to the female parent (0.659 3), and F7 generation was more close to the male parent (0.5788). To the sporophytes study in 24 selected primers for RAPD amplification, 191 loci ranging from 230-2 800 bp were obtained, in the average to each primer of 8.0 loci. The heterozygosity to six populations were male parent (0.223 9),female parent (0.107 2), F6 (0.216 4), F7 (0.228 6), F8 (0.229 6) and F9 (0.317 2). The nearest genetic distance was 0.083 5 (Fs, F9). Total heterozygosity (HT) ofF6, F7, F8 and F9 generations was 0.318 6, the average heterozygosity (Hs) for F6,F7, F8 and F9 generations was 0.248 0, and deduced coefficient of population differentiation (Gst) was 22.2%. Six sequence characterized amplified regions (SCAR) were preliminary screened through RAPD analysis. It needed to be verified in detail as they are significant for molecular marker assistance in breeding and selecting Laminaria.     

镁载体分离-丁基罗丹明B萃取光度法测定钽矿石中的钽

试样经碱熔融后,在高浓度钠盐存在的强碱性介质中,用镁作载体使钽沉淀完全而达到与钨、锡、钼、钒、硅等元素的分离,在硫酸介质中,钽与丁基罗丹明B形成红色络合物,用甲苯-丙酮混合萃取剂萃取,有机相在560nm处比色测定。其检出限:12×10-6五氧化二钽,测定范围:20×10-6～1.0×10-2五氧化二钽     

原子吸收法测定矿石中的锂铷铯

本文研究了锂、铷、铯三元素在丙酮有机溶剂中的行为,测定条件,干扰离子的影响及消除,使灵敏度分别比在水相中提高为2.5—3.5倍。方法灵敏度高,干扰少,测定范围为0～5PPM,适用于矿石中微量锂、铷、铯三元素同时测定。     

萃取催化动力学分析法测定铁矿、铝合金和土壤中痕量铜

双硫腙(H2Dz)是一种常用的螯合萃取剂，多用于光度法测定金属离子。以H2Dz作还原剂建立的萃取催化动力学分析法已用于Cu(Ⅱ)，Cr(Ⅵ)，NO^-2等的测定。本文采用该法对铁矿、铝合金和土壤中的痕量铜进行测定，结果满意。该法具有灵敏度高，操作简便，试样用量少，中止指示反应简单等优点。     

高效液相色谱-荧光检测同时测定污泥中7种氟喹诺酮类抗生素

为了监测污泥中氟喹诺酮类抗生素(FQs)的含量和水平,建立了基于固相萃取高效液相色谱荧光检测法测定污泥中7种FQs的分析方法。污泥样品选用乙腈∶磷酸盐缓冲液(1∶1,V∶V)(pH=3)提取,以亲水亲油平衡(hydrophilic-lipophilic balance, HLB)小柱净化富集,经甲醇洗脱、浓缩后用高效液相色谱荧光检测器(HPLC-FLD)检测,采用乙腈/0.1%的甲酸作为流动相并以外标法定量。FQs在0.005～1.0 mg/L浓度范围内呈现良好线性关系,R2为0.992 7～0.999 8。添加量为0.05、0.5和1.0 mg/kg时,污泥中7种氟喹诺酮类的加标回收率为78.3%～106.4%,其相对标准偏差为3.68%～12.06%(N=5)。方法的检出限为0.001～0.01 mg/kg,方法定量限为0.004 6～0.038 4 mg/kg。用该方法对北京地区3个污水处理厂活性污泥样品中7种FQs进行分析,检出浓度范围为未检出至1.09 mg/kg。     

t-BAMBP/磺化煤油萃取体系从盐湖卤水中萃取铷的动力学研究

采用上升单液滴法,进行盐湖卤水中萃取铷的动力学研究,主要考察了比界面积、水相铷浓度和油相(t-BAMBP/磺化煤油)浓度对萃取速率的影响。通过比界面积的研究发现,t-BAMBP萃取铷的过程由界面化学反应和相内化学反应共同控制;通过对实验数据的非线性拟合,得到了萃取体系的动力学方程,R=9.936×10-7[Rb+]1.134[t-BAMBP]2.190,萃取速率对铷的反应级数为a=1.134,对t-BAMBP反应级数b=2.190,实验值和计算值的均方根误差为1.735%。