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为提高第2代新烟碱类杀虫剂噻虫胺与噻虫嗪的产品纯度,降低其在工业生产中的废水排放量,对噻虫胺中间体1,5-二甲基-2-硝基亚胺基-全氢-1,3,5-三嗪和噻虫嗪中间体3-甲基-4-硝基亚胺四氢-1,3,5-噁二嗪的反应机理进行研究。发现噻虫胺中间体1,5-二甲基-2-硝基亚胺基-全氢-1,3,5-三嗪的合成在碱性条件下进行,而噻虫嗪中间体3-甲基-4-硝基亚胺四氢-1,3,5-噁二嗪的合成既可在酸性也可在碱性条件下进行,酸性条件下产品收率更高,且都符合Mannich反应机理。Mannich反应在有机化学合成,特别是在药物合成方面具有非常重要的地位,展望了其在农药合成领域的发展趋势。 相似文献
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采用共价有机骨架MCTP-1为载体材料,6-苄氨基嘌呤为虚拟模板,采用沉淀聚合的方法合成噻虫嗪表面分子印迹聚合物(MCTP-1@MIPs)。利用红外光谱、扫描电镜和X-射线衍射对所合成的聚合物进行表征。吸附测试表明,在0.5~30μg/mL测定范围内最大吸附量可达8.81μg/mg,且10 min即可达吸附-解析平衡,聚合物对噻虫嗪的印迹因子为2.04,对于噻虫嗪具有高选择性。将聚合物作为柱填料,制备成固相萃取柱,优化固相萃取柱使用条件,使用高效液相色谱-二极管阵列检测器进行检测,建立一种灵敏可靠的检测噻虫嗪的方法。为水中噻虫嗪残留的分离富集检测提供了新思路。 相似文献
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对噻虫嗪中间体3-甲基-4-硝基亚胺基四氢-1,3,5-噁二嗪的合成进行研究。通过优化反应条件,使产品转化率达到90%以上,同时收率也能达到85%以上,高于以往的文献报道值。该方法操作简便,适用于工业化生产。 相似文献
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In this study, regulated, unregulated exhaust emissions and fuel consumption with diesel fuel and palm-based biodiesel blends at proportions of 5%, 20% and 40% (v/v) have been investigated. A Euro 3 compliant light duty vehicle was tested on a chassis dynamometer over the new European driving cycle (NEDC) and the non-legislated Athens driving cycle (ADC). The experimental results showed that the addition of biodiesel increased NOx emissions. This increase was more significant with the use of B20 over both cycles (13.7% and 23.2% over the NEDC and ADC, respectively). Biodiesel addition resulted to increases in CO emissions with the highest increase being 11.78% for B20 over NEDC and 11.62% for B40 over ADC. HC emissions increased with biodiesel over the NEDC, while over the ADC the addition of biodiesel led to reductions with the highest being with the use of B40 (about 26.47%). The same observation holds for PM emissions. Over the ADC the most beneficial reduction was in the order of 50% for the B40. CO2 emissions and fuel consumption followed similar patterns. B20 led to increases up to 6.16% and 2.94% in fuel consumption over NEDC and ADC, respectively. Some PAH compounds demonstrated an increase with biodiesel, while nitro-PAHs decreased with most of them being almost undetectable. Most carbonyl emissions decreased with biodiesel. 相似文献
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在固定床微型反应器中,以HZSM-5(硅铝物质的量比为25)分子筛为催化剂,探讨了甲醇对噻吩催化脱硫转化反应的影响。实验表明,反应温度在350 ℃以上时,噻吩转化率达到51%以上;甲醇与溶剂苯的合适体积比为1∶2;负载于HZSM-5的氧化镧对噻吩的催化转化有较大的促进作用;负载氧化镧质量分数为1.0%时,噻吩的转化率和硫化氢的产率分别达到51.3%和18.1%,与母体HZSM-5分子筛催化剂相比,噻吩的转化率和硫化氢的产率分别提高了36.0%和11.9%;空速以14 h-1为宜。 相似文献