Determination of 19 Organophosphorous Pesticides Residues in Milk Drink and Milk Powder by Gas Chromatography-Negative Chemical Ionization-Mass Spectrometry

将气相色谱-负离子化学源质谱法(GC-NCIMS)应用于牛奶饮品和奶粉中19种有机磷农药残留的同时分析。牛奶饮品和奶粉经乙腈提取剂超声提取、Florisil硅藻土和中性氧化铝双净化剂同时净化及正己烷-乙酸乙酯(体积比1∶1)混合洗脱剂洗脱后,以三苯基磷酸酯为内标物,采用GC-NCI MS的选择离子监测方式(SIM)定性与定量分析。当牛奶饮品和奶粉的加标浓度水平为20、100、500μg/kg时,平均加标回收率为64.5%~129%,相对标准偏差为2%~20%;除喹硫磷的方法检出限(MDL)为2.4μg/kg外,其余18种有机磷农药的MDL均小于1.0μg/kg;线性范围为10~500μg/kg,相关系数均大于0.9988,此分析方法成功地应用于牛奶饮品和奶粉中多种痕量有机磷农药残留的分析。A rapid method was developed for the determination of 19 organophosphorous pesticides residues in commercial milk drink and milk powder.Under optimized conditions,the pesticides were extracted from milk drink or milk powder with acetonitrile in an ultrasonic bath and cleaned up on a Florisil and neutral alumina column,and were determined by gas chromatography with negative chemical ionization mass spectrometric detection in the selected ion monitoring mode with triphenyl phosphate as internal standard.The recoveries for all the pesticides studied ranged from 64.5% to 129% with a relative standard deviation range of 2%-20%.The detection limit of the method was less than 1.0 μg/kg for most of the pesticides except for the quinolphos.The linear ranges of the calibration curves ranged from 10 μg/kg to 500 μg/kg with correlation coefficients of 0.998 8.The proposed method was successfully applied to the analysis of these compounds in milk drink and milk powder

Determination of Five Polybrominated Diphenyl Ether Residues in Deep-Sea Fish Oil Using Gas Chromatography-Negative Chemical Ionization/Mass Spectrometry

建立了气相色谱-负离子化学电离质谱法(GC-NCI/MS)同时分析深海鱼油食品中5种多溴联苯醚残留的分析方法。深海鱼油食品用正己烷超声提取、中性与酸性硅胶色谱柱净化和正己烷洗脱后,以PCB103为内标物,采用GC-NCI/MS的选择离子监测方式(SIM)分析;同时探讨了5种多溴联苯醚的NCI/MS特征离子的断裂机理。当空白深海鱼油食品的加标浓度为20.0和100.0μg/kg时,加标回收率为88.6%-111.3%,相对标准偏差为3.8%-13.5%,方法的检测限为0.77-1.34μg/kg,线性范围为1.0-500.0μg/kg,相关系数均大于0.999 2。此方法已成功地应用于深海鱼油食品中5种痕量多溴联苯醚残留的同时分析。Polybrominated diphenyl ethers(PBDEs) are a kind of brominated flame retardants(BFRs),which refer to compounds used in some plastics to impede or even suppress the combustion process.As the emission or disposal of plastics,PBDE residues have been found in both environment and biota.In this work,an analytical method was developed for the simultaneous determination of 5 PBDE residues in deep-sea fish oil.PBDEs were extracted from deep-sea fish oil with n-hexane,cleaned up on a silical gel column,and determined by using gas chromatography-negative chemical ionization/mass spectrometry(GC-NCI/MS) in the selected ion-monitoring(SIM) mode,with PCB103 as the internal standard.Meanwhile,the characteristic ion and fragmentation mechanism of some PBDEs in NCI/MS were evaluated.Recovery studies were performed at 20.0 and 100.0 μg/kg fortification levels for each PBDE,and the recoveries ranged from 88.6% to 111.3% with relative standard deviations between 3.8% and 13.5% for different PBDEs.The limits of detection(LOD) were from 0.77 to 1.34 μg/kg for different PBDEs.The developed method was linear over the range assayed,1.0-500.0 μg/kg,with correlation coefficients larger than 0.999 2.The developed method has also been successfully applied to the determination of PBDEs in several deep-sea fish oil samples and the three most abundant PBDEs(PBDE-47,PBDE-99 and PBDE-100) were found

新型水泥基复合墙体材料的研究和应用

以水泥为胶凝材料,粉煤灰和矿粉作为掺和料,中砂和闭孔玻化微珠作为细骨料,无机质保温防火粗骨料作为保温防火粗骨料制备密度为800 kg/m~3的新型水泥基复合墙体材料,基于强度、吸水率和热工性能要求,采用正交法试验选择最优配合比,探讨了保温防火粗骨料、引气剂掺量、玻化微珠和中砂掺量对材料的物理性能和保温性能的影响规律,结果表明,通过优化可研制出既具有优异的物理性能又具有良好保温隔热性能的复合墙体材料。</p

无机-有机杂化絮凝剂在陶瓷废水处理中的应用

陶瓷废水中颗粒粒度细,依靠重力沉降速率慢,需借助絮凝提升其沉降特性,以加快其与废水的分离。笔者研究了实验室自制无机-有机杂化絮凝剂HLM在某陶瓷厂陶瓷废水处理中的应用。实验结果表明,当HLM加入量为5mg/L时,可将陶瓷废水的上清液浊度降低至19.42NTU。与生产使用絮凝剂相比,HLM可将陶瓷废水的药剂处理成本降低40%～50%。</p

同源四倍体水稻亲本材料的结实研究

研究了2份二倍体水稻和29份同源四倍体水稻(2n=4x=48)亲本(其中4份低代材料、25份高代材料)在2004年和2005年的结实情况.与二倍体对照相比,同源四倍体材料的花粉育性、结实率均不同程度下降,尤其低代材料的花粉育性(59.6%～65.3%)和结实率(26.8%～33.5%)大幅度降低;但经过选择改良,大多数材料的花粉育性和结实率均不同程度提高.F检验表明,同源四倍体不同品种间各性状均差异显著,说明同源四倍体材料具有很大的改良潜力.从1996年到2005年对部分同源四倍体水稻进行了连续选择改良

不同胶凝材料对氰化废渣的固化性能研究

采用胶凝材料固化技术,以不同类型胶凝材料为固化剂,对氰化废渣进行固化处理。结果表明:与硅酸盐水泥(PC)、铝酸盐水泥(AC)和硫铝酸盐水泥(SAC)相比,改性硫氧镁水泥(MOC)固化剂所得固化体的强度性能最优;固化体中CN-的浸出率大小顺序为R_(AC)&gt;R_(SAC)&gt;R_(PC)&gt;R_(MOC),固化体中CN~-的累积浸出分数AC&gt;SAC&gt;PC&gt;MOC;在MOC固化体系中,部分氰化废渣还参与了胶结反应,一方面促进了强度的增长,另一方面阻碍了CN~-的浸出。</p

Determination of five polybrominated diphenyl ethers in tea leaves by gas chromatography-mass spectrometry-negative chemical ionization

将气相色谱-负离子化学源-质谱法(GC-NCI-MS)应用于快速分析茶叶中5种多溴联苯醚残留量。茶叶样品以正己烷作为提取剂,采用超声辅助提取法,提取液经中性氧化铝和Florisil硅藻土层析柱净化和正己烷洗脱后,以PCB-103为内标物和GC-NCI-MS的选择离子监测方式(SIM)进行定性与定量分析。5种多溴联苯醚的平均加标回收率为70.9%~81.7%,相对标准偏差为6.9%~11.0%,方法检出限小于0.12μg/kg,线性范围为0.1~500μg/kg,相关系数都大于0.9990。所分析的8种茶叶样品中6种含有微量的PBDE-47,1种茶叶样品含有微量的PBDE-99。A rapid method based on ultrasonic extraction was developed for the determination of five polybrominated diphenyl ethers in tea leaves.Hexane was used as the extraction solvent and elution solvent,after the extraction was cleaned by the cartridge filling with alumina and Florisil,the analysis of samples was accomplished using gas chromatography with negative chemical ionization mass spectrometric detection(GC-NCI-MS) in the selected ion monitoring mode(SIM),and with PCB-103 as internal standard(IS).The average recoveries of the standard samples spiked ranged from 70.9% to 81.7% with relative standard deviation between 6.9 and 11.0% for the five different polybrominated diphenyl ethers(PBDEs),and the detection limit of the method was smaller than 0.12 μg/kg.The lineer range is from 0.1 to 500 μg/kg,and the correlation coefficients were larger than 0.9990.Six out of the eight determinated tea leaves had PBDE-47,and one had PBDE99

不同胶凝材料对氰化废渣的固化性能研究

采用胶凝材料固化技术,以不同类型胶凝材料为固化剂,对氰化废渣进行固化处理。结果表明：与硅酸盐水泥（PC）、铝酸盐水泥（AC）和硫铝酸盐水泥（SAC）相比,改性硫氧镁水泥（MOC）固化剂所得固化体的强度性能最优;固化体中CN-的浸出率大小顺序为R（AC）〉R（SAC）〉R（PC）〉R（MOC）,固化体中CN--的累积浸出分数AC〉SAC〉PC〉MOC;在MOC固化体系中,部分氰化废渣还参与了胶结反应,一方面促进了强度的增长,另一方面阻碍了CN^-的浸出

氰化渣典型矿物对氰的吸附

氰化提金过程中产生大量的氰化渣,被视为是危险固体废物。氰化渣主要由黄铁矿、石英和硅酸盐等矿物组成。本实验采取静态吸附法,模拟了氰化渣中几种典型矿物及其复合矿物对氰的吸附。研究表明:矿物对氰的吸附呈线性特征,但吸附能力各不相同,各矿物对氰的吸附量大小顺序是q_(黄铁矿)>q_(模拟氰化渣)>q_(硅酸盐矿)>q_(石英);石英对氰几乎不产生吸附,黄铁矿、硅酸盐矿物混合物和模拟氰化渣对氰的饱和吸附量分别约为13.89、1.09和6.89 mg/g。开发了一种数学模型用来评估石英、硅酸盐矿物混合物和黄铁矿含量对氰化渣吸附氰总量的影响。红外分析表明,CN-吸附在矿物表面,改变了氧化产物,生成了新的物质,促进了矿物对CN-的吸附

氰化渣典型矿物对氰的吸附

氰化提金过程中产生大量的氰化渣,被视为是危险固体废物。氰化渣主要由黄铁矿、石英和硅酸盐等矿物组成。本实验采取静态吸附法,模拟了氰化渣中几种典型矿物及其复合矿物对氰的吸附。研究表明:矿物对氰的吸附呈线性特征,但吸附能力各不相同,各矿物对氰的吸附量大小顺序是q_(黄铁矿)>q_(模拟氰化渣)>q_(硅酸盐矿)>q_(石英);石英对氰几乎不产生吸附,黄铁矿、硅酸盐矿物混合物和模拟氰化渣对氰的饱和吸附量分别约为13.89、1.09和6.89 mg/g。开发了一种数学模型用来评估石英、硅酸盐矿物混合物和黄铁矿含量对氰化渣吸附氰总量的影响。红外分析表明,CN-吸附在矿物表面,改变了氧化产物,生成了新的物质,促进了矿物对CN-的吸附