填充柱气相色谱法测定土壤中的六种有机磷农药

利用玻璃填充柱,选用DFTPP(十氟三苯基磷)作内标,用气相色谱-火焰光度检测法(GC-FPD),对土壤中的6种有机磷农药进行了检测.结果表明,该方法灵敏度高,定量准确,消除了外标法定量误差的影响.     

微胶囊壁材在医药和农药领域研究新进展

介绍了微胶囊壳材料选择的原则，并对医药和农药微胶囊化所用壁材总结分类，分析了各类壁材的优缺点，综述了一些新开发的壁材材料或旧壁材的新应用。     

有机农药污染的植物修复研究进展

植物修复具有诸多优点，是有机农药生物修复的有效途径之一，主要包括植物的吸收、植物酶的降解以及植物根际环境联合作用等一系列修复作用。简述了植物修复的概念及其研究历史，系统综述了有机农药植物修复的机理和植物修复模型，并以滴滴涕植物修复为例阐述了利用植物对农药进行修复的研究成果与应用，阐述了今后进一步研究的重点。     

TiO2光催化降解农药废水的研究

研究了TiO2光催化降解有机磷农药乐果废水的影响因素,获得的适宜工艺条件为：TiO2用量 0.4 g/L,乐果初始浓度 20 mg/L,曝气量 23 L/h,在强酸性及碱性介质中均有利于乐果废水的降解.加入电子接受体Fe3＋、H2O2能较大地提高乐果废水降解率.     

N-(2-氟-4-氯-5-环戊氧基苯基)氨基甲酸乙酯的合成

环戊口恶草酮是一种新型口恶唑啉二酮类除草剂,N-(2-氟-4-氯-5-环戊氧基苯基)氨基甲酸乙酯是合成该除草剂的重要中间体之一.本文以5-硝基-2-氯-4-氟苯酚为原料,经催化加氢还原、烷基化反应等合成了N-(2-氟-4-氯-5-环戊氧基苯基)氨基甲酸乙酯.该方法操作简便,四步总收率达56.7%.     

Removal of pesticides from wool wax by continuous countercurrent dual-solvent extraction

Pesticide residues in raw wool wax were removed to below detectable levels by continuous countercurrent extraction with hexane and N,N-dimethylformamide (DMF) in a pilot-scale mixer-settler contactor. The disengagement of the phases in the settling compartments was promoted by the addition of a small amount of formic acid (3% vol/vol) to the DMF-rich feed. Empirical equations were developed to predict the effect on the pesticide partition coefficients of the wool wax concentration, the presence of small amounts of water, ethanol, and/or isopropanol in the solvents, and the temperature used in the contactor. These empirical equations were included in equations that describe the concentration of the pesticides in the different stages of the contactor and were used to develop a spreadsheet model that accurately predicted the mixer-settler’s performance. The raffinate wool wax produced by this process after conventional neutralization met all BP and USP specifications for pharmaceutical lanolin.     

吡啶类农药的研究进展(续)

本文根据具有生物活性的吡啶衍生物的结构特征，简要分类叙述了近10年来含吡啶类农药的研究进展。     

醋酸纤维素氨基甲酸酯的合成及其膜性能的研究

研究了用甲苯二异氰酸酯对醋酸纤维素进行改性,合成醋酸纤维素氨基甲酸酯,以增强高聚物的物理性能和耐菌性能。探讨了反应时间、原料配比、反应温度、催化剂用量及产物分离用溶剂等因素对此高聚物材料合成的影响。对醋酸纤维素苯基氨基甲酸酯铸成的反渗透膜的水通量、脱盐率、耐水解和耐微生物的稳定性能的测试表明,经改性的醋酸纤维素膜具有较好的上述性能,是一种良好的膜材料。     

我国农药工业现状及发展形势

近年来,我国农药工业发展迅速,国内需求量和出口量增长很快,但是,与发达国家相比,我国农药工业还有很大差距。为提高中国农药工业的整体竞争力,国家发改委将出台一系列政策,抬高农药工业的准入门槛,淘汰一批环境污染严重的企业,因此,我国现有农药企业和拟进入农药行业的企业应做好准备工作。     

Transparency-tunable and moderate-temperature healable thermoplastic polyurethane elastomer based on bisphenol A chain-extender

Transparent self-healing polymers have a promising future, but the research on the relationship among transparency, self-healing, and structure is still challenging. The thermoplastic polyurethane elastomers containing aryl carbamate were prepared by the reaction of isocyanate-terminated prepolymer and chain-extender bisphenol A (BPA). On the one hand, the thermoplastic polyurethane elastomer could heal at a relatively low temperature due to the exchange of aryl carbamate, and exhibits 83% of healing efficiency at 90°C for 2 h. On the other hand, two methyl groups of BPA hinder the crystallization of hard segments in polyurethane, so the domain of hard segments is amorphous, while the microcrystals of soft segments dispersed in the polyurethane are affected by the content of hard segments, therefore, the transparency of polyurethane can be tailored by the content of hard segments. It provides a simple design and a feasible preparation method for transparent self-healing polymer.