Tea bag filter paper as a novel protective membrane for micro-solid phase extraction of butachlor in aqueous samples

An innovative, cost-effective, simple, and environmental friendly tea bag filter paper protected micro-solid phase extraction (μ-SPE) technique was developed for the first time with the aim to miniaturize and minimize the use of organic solvents for the extraction and determination of butachlor in aqueous samples. The μ-SPE device was produced by packing 3.0 mg of an easily synthesized new sorbent, hydroxyl-functionalized polypyrrole (OH-PPY), inside a small tea bag filter paper sachet (1.0 cm × 0.5 cm) that served as a protective envelope. Both the extraction and desorption procedures were facilitated by sonication. Due to the high porosity and the fast water absorption of the tea bag filter paper, the analyte could easily diffuse through and enhance the interaction with the sorbent. Under the optimized conditions for the GC-ECD and the μ-SPE, the limit of detection (S/N ≥ 3) was 2.0 μg L^?1 while the limit of quantitation (S/N ≥ 10) was 10.0 μg L^?1. The recoveries of the butachlor spiked at 0.050, 0.10, and 0.50 μg mL^?1 ranged from 77.9 ± 3.0 to 112.5 ± 2.9%. The proposed method was successfully applied for the determination of butachlor in water samples from paddy cultivation sites. The levels found were from non-detectable to 24.71 ± 0.37 μg L^?1.     

微波消解火焰原子吸收光谱法测定茶叶中的锌

采用微波消解样品,用火焰原子吸收法直接测定茶叶中的锌含量。回收率85.98%~118.62%,相对标准偏差为1.7%。方法准确、操作简便,可实现同一样品的快速测定,且最大限度地减少了对测定的干扰。微波消解作为一种样品制备方法,在茶叶样品预处理方面,避免了传统湿法消解的限制,具有传统碱式干法消解与酸浸提法无法比拟的优点。     

我国热带地区胶-茶-鸡农林复合系统物质循环研究

以海南省文昌市典型的胶-茶-鸡农林复合模式为研究对象 ,以单作胶园、胶茶间作园为对照 ,采用定量研究与定性分析相结合的方法 ,研究其物质循环规律。结果表明 ,胶-茶-鸡农林复合系统的氮、磷输入、输出量最大 ,系统外物质投入率比另两系统明显减少 ,系统内养分循环量增加 ,因此 ,该系统具有较合理的物质循环结构。     

TAS-986型石墨炉原子吸收光谱法测定绿茶中微量硒

利用加入基体改进剂NiNO3,采用TAS-986型石墨炉原子吸收光谱法对绿茶中微量硒的分析.RSD＜5.0%,回收率在99.0%～100.2%之间,该法简便、快速,测定结果准确可靠.     

陕南富硒茶的分布与开发利用

对陕南主要茶区进行了茶叶和茶园土壤的系统采样和分析,并对富硒茶的硒量作了初步探讨.建议用富硒茶作为低硒区人体硒的补充来源.讨论了富硒保健茶的含硒标准.提出了陕南富硒保健茶的分布范围和含硒水平.     

油茶饼粕综合利用新工艺

本文综述了油茶饼粕综合开发利用的工艺方法及其优缺点。结果表明,用单一有机溶剂一步浸取同时提取饼粕中的油脂和茶皂素的新方法,具有工艺简单,设备投资少,产品产量高,质量好且稳定等优点。     

TAS-986型石墨炉原子吸收光谱法测定绿茶中的微量硒

利用加入基体改进剂NiNO3，采用TAS-986型石墨炉原子吸收光谱法，对绿茶中的微量硒进行测定分析，结果RSD〈5．0％，回收率在99．0％-100．2％之间。该法简便、快速，测定结果准确可靠。     

吸烟烟气对鼠肺细胞膜的损伤和茶多酚的保护作用

本文以香烟气相物质作用鼠肺细胞膜为模型,用脂肪酸自旋标记物5-DOXYL和16DOXYL分别研究膜浅层和深层的动态性质受气相烟的影响,并用紫外可见分光光度法研究气相烟对膜脂的作用。结果发现,在实验的气相烟流量下,香烟气相物质能引发鼠肺细胞膜的脂质过氧化,并且使膜浅层的流动性增大。但对膜深层的动态性质没有明显的改变,如果在鼠肺细胞中预先加入粗晶态或粉态茶多酚。则肺细胞的过氧化和膜的动态性质改变受到抑制,而且这种抑制作用与茶多酚浓度呈量效关系,而茶多酚本身对膜浅层无明显作用,但对膜深层的流动性有一定影响,而且两种茶多酚的作用相似。     

亚热带茶园土壤的某些生物化学性状研究

茶园土壤的有机质含量、腐殖质组成、有机碳的循环与平衡特点、酶活性及其在施肥条件下的变化情况与土壤肥力密切相关．试验结果表明：亚热带茶园土壤有机质含量水平较低，腐殖质组成中以富里酸为主，HA／FA比、酶活性均比起源土壤略低；高产茶园土壤有机碳库的循环水平较高，在不施有机肥的情况下仍能保持平衡；低产茶园土壤有机碳库的循环水平较低，输出大于输入，施用有机肥可以较快地提高茶园土壤有机质含量和酶活性水平．增施有机肥和实行茶林复合是培肥茶园土壤、提高茶园生产力的有效措施．     

Study of ciprofloxacin removal by biochar obtained from used tea leaves

In this study,used tea leaves(UTLs) were pyrolyzed to obtain used tea-leaf biochar(UTC),and then the UTC was used as an adsorbent to remove ciprofloxacin(CIP) from aqueous solutions.Batch experiments were conducted to investigate the CIP adsorption performance and mechanism.The results showed that the CIP-adsorbing ability first increased and then declined as the UTC pyrolysis temperature increased.The UTC obtained at 450°C presented excellent CIP-absorbing ability at p H 6 and 40°C.The maximum monolayer adsorption capacity was 238.10 mg/g based on the Langmuir isotherm model.The pseudo-second-order kinetic equation agreed well with the CIP adsorption process,which was controlled by both external boundary layer diffusion and intra-particle diffusion.The characterization analysis revealed that the \OH groups,C_C bonds of aromatic rings,C\H groups in aromatic rings and phenolic C\O bonds play vital roles in the CIP adsorption process,and that the N\C,N\O,O\C_O and C\OH groups of UTC were consumed in large quantities.π–π interactions,hydrogen bonding and electrostatic attraction are inferred as the main adsorption mechanisms.The present work provides not only a feasible and promising approach for UTLs utilization but also a potential adsorbent material for removing high concentrations of CIP from aqueous solutions.