排序方式: 共有39条查询结果,搜索用时 552 毫秒
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建立丹磺酰氯柱前衍生-超高效液相色谱-串联质谱法测定人体尿样中环己胺的方法。冷冻样品经解冻、离心后,用丹磺酰氯衍生,固相萃取小柱净化。目标化合物采用 Waters ACQUITY CSHTM C18色谱柱(50 mm×2.1 mm,1.7μm)分离,以甲醇和0.002 mol/L乙酸铵溶液为流动相梯度洗脱,采用电喷雾离子源电离、正离子多反应监测模式质谱检测。环己胺在2.5~200μg/L浓度范围内有较好的线性关系,相关系数大于0.999,回收率为98.7%~102.3%,精密度为3.1%~5.2%,检出限和定量限分别为1.0和3.0μg/L。结果表明,本方法操作简单、准确可靠,可适用于人体尿液中环己胺的定量分析。应用本方法测定200份学生尿液样品,环己胺检出率为34.5%。 相似文献
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螯形二羟基主体分子的包结性能与其结构关系的研究 总被引:4,自引:0,他引:4
报道了螯形主体分子,反式-9,10-二-1'-萘基-9,10-菲二醇(1), 能与多种含氮有机化合物,诸如喹啉、异喹啉、哌啶、二环已胺等形成包化合物; 而反式-9,10-二苄基-9,10-菲二醇(2)则不具有包结性能。还报道了这些 包结化合物的IR,粉末XRD的表征,用~1H NMR谱测定了它们的分子摩尔比,分别为 (1)/喹啉(1:2), (1)/异喹啉(1:2),(1)/哌啶(1:2)和(1)/二环忆胺 (1:2)。用单晶X射线衍射法测定了(1)与二环忆胺包结物以及(2)的结构,结果 表明前者属正交晶系,空间群为Pnca(标准型Pbca),晶胞参数: a = 1.6714(3) nm, b = 1.6875(3) nm, c = 1.7224(3) nm, V = 4.858 nm~3, Z = 8,形成了隧 道型配位笼状包合物。后者属三斜晶系,空间群为P1-bar,晶胞参数: a = 0. 8058(2) nm , b = 0.9715 (2) nm, c = 1.4437(3) nm, α = 109.59(3)°, β = 95.96(3)°, γ = 96.03(2)°, V = 1.0471 nm~3, Z = 2, 还比较了(1)和(2) 的结构差异,分析了(1)的结构和包结性能的关系。 相似文献
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ZHAOZhen-hua 《高等学校化学研究》2003,19(3):350-354
We substituted several environmentally friendly catalysts which included HY and H-β zeolites, various cation-exchanged β zeolites, and solid-supported ferric chloride for conventional catalysts for the synthesis of 3-(1-cyclohexenyl)-2-butanone from the reaction of ethylidenecyclohexane with acetic anhydride at room temperature. HY zeolite was found to be the most effective for this reaction, and gave the acYlated product in a 72% yield under the conditions of n(ethylidenecyclohexane)/n(acetic anhydride)/m(HY zeolite)= 1 mmol/10 mmol/0. 100 g, reaction temperature 25 ℃ and reaction time 2 h. The used HY zeolite can be recovered, regenerated and gave almost the same yield as the fresh one. The lifetime of the HY zeolite is over 80 h. The effect of different factors on the reaction has also been investigated. 相似文献
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环己基马来酰亚胺的合成 总被引:2,自引:0,他引:2
用浓硫酸和三乙胺共催化环己基马来酰胺酸脱水关环合成环己基马来酰亚胺。探讨了催化剂、反应溶剂等对反应的影响。 相似文献
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1 INTRODUCTION Crystal engineering of inorganic/organic hybrid materials has provoked significant interest in their new structural architectures and potential applica- tions to the fields of photochemistry, electromagne- tism, catalysis, medicine, bio… 相似文献