浓缩当归丸的提取工艺研究

采用索氏提取法提取浓缩当归丸的有效成分阿魏酸，同时用正交分析法对提取溶剂种类、用量及提取时间进行考察，最后以高效液相色谱法(HPLC)测定阿魏酸的含量，从而筛选出最佳提取工艺．结果显示：选用60mLV甲醇：V甲酸=95：5的混合液作为提取溶剂．预先浸泡24h，再索氏提取3h，得到浓缩当归丸的有效成分阿魏酸的含量最高．     

Organic Synthesis in Ionic Liquids： Condensation of 3-Methyl-1- phenyl-5-pyrazolone with Carbonyl Compounds Catalyzed by Ethylenediammonium Diacetate （EDDA）

The derivatives of pyrazolone are important class of antipyretic and analgesic compounds1. 1-Phenyl-3-methyl-4-arylmethylene-5-pyrazolones are very useful inter- mediates in the synthesis of substituted pyrazolones, generally, which were prepared by the c…     

下缘芳香取代结构对杯[4]芳烃Langmuir膜的影响

The Langmuir monolayer properties of lower rim aromatically substituted calix[4]arenes, 5,11,17,23-tetra-tert-butyl-25,27-bis（2-naphth-1＇-ylacetylaminoethoxy）-26,28-dihydroxylcalix[4]arene （BNAEC）, 5,11,17,23-tetra-tert- butyl-25,27-bis（2-benzoylamino ethoxy）-26,28-dihydroxylcalix[4]arene （BBAEC） and 5,11,17,23-tetra-tert-butyl- 25,27-bis（2-cinnamoylaminoethoxy）-26,28-dihydroxylcalix[4]arene （BCAEC）, have been studied. Film balance measurements and Brewster angle microscopy （BAM） observation demonstrate that all the compounds can form Langmuir monolayers with different molecular limiting areas. BNAEC or BBAEC monolayer is able to form condensed domains during compression, while BCAEC monolayer can never form condensed domain. BNAEC monolayer is more readily to form condensed domain than BBAEC monolayer. Moreover, BNAEC monolayer can form the total condensed phase during compression even when T=28℃, while BBAEC monolayer can not when T 〉 10 ℃. The results imply that different lower rim aromatic substitutions affect essentially the intermolecular interaction and molecular packing in the monolayer at air/water interface.     

激光工艺雕刻双色板挥发性物质气相色谱-质谱分析

激光工艺雕刻过程中,聚合物材料会产生难闻的气味,释放出有毒有害的挥发性物质,严重污染了周边空气质量,损害了附近居民的身体健康。目前,该行业排放废气的主要污染物成分和含量,以及如何监控等问题国内外均未见文献报道。本文开展对激光工艺雕刻产生挥发性物质的分析,对于确定     

The Condensation of Aromatic Aldehydes with Acidic Methylene Compounds in Water

The condensation of aromatic aldehydes with acidic methylene compounds such as malononitrile, methyl cyanoacetate, cyanoacetamide, 5,5-dimethyl-1,3-cyclohexanedione,bartbituric acid and 2-thiobarbituric acid proceeded very efficiently in water in the presence of triethylbenzylammonium chloride (TEBA) and the products were isolated simply by filtration.     

Synthesis of Novel 1-Arylsulfonyl-4-（1＇-N-2＇, 3＇, 4＇, 6＇-tetra-O-acetyl-β-D-glucopyranosyl）thiosemicarbazides

The synthesis of novel 1-arylsulfonyl -4- （1＇-N -2＇, 3＇, 4＇, 6＇-tetra-O-acetyl-β-D-gluco- pyranosyl） thiosemicarbazides via condensation of 2, 3, 4, 6-tetra-O-acetyl-β-D-glucopyranosyl isothiocyanate with substituted phenylsulfonyl hydrazines was described. Their structures and physical properties were confirmed by ^1H NMR, ^13C NMR spectra, elemental analysis and MS.     

固相萃取-高效液相色谱法同时测定噻菌灵和多菌灵在浓缩菠萝汁中的残留量

建立了一种可同时测定浓缩菠萝汁中噻菌灵和多菌灵残留量的反相高效液相色谱分析法。浓缩菠萝汁样品与水按一定比例稀释后,经过调节溶液的pH值、离心、过滤,用混合相固相萃取小柱(Mixed-mode SPE)进行提取、净化,并用配有二极管阵列检测器(DAD)的液相色谱仪检测,外标法定量。使用噻菌灵和多菌灵对照品进行添加回收率测定,结果显示,本方法对噻菌灵的检出限为0.020 mg/kg,回收率为75.7%~93.3%;对多菌灵的检出限为0.020 mg/kg,回收率为80.8%~99.2%;测定的相对标准偏差均不大于5.7%。本方法简单、快速、准确,能满足常规噻菌灵和多菌灵残留量检测的需要。     

特丁基二甲基硅烷衍生化气相色谱-质谱联用法快速测定苹果汁中的棒曲霉素

运用特丁基二甲基硅烷(TBDMS)衍生化气相色谱-质谱(GC-MS)联用法快速、高灵敏地测定了苹果汁中的棒曲霉素(PAT)。样品用乙酸乙酯-正己烷提取,Carb/C18混合型固相萃取柱净化,TBDMS衍生,GC-MS测定,选择离子监测(SIM)模式,外标法定量。在0.01～1 mg/L的范围内线性良好(r＞0.98),在2～50 μg/kg的添加水平范围内,平均回收率为88%～98%,相对标准偏差(RSD)为5.3%～13.6%, PAT的检出限为0.5 μg/kg,测定低限为2 μg/kg。该方法快速、高灵敏、准确、专一、耐用,适合对苹果汁中PAT进行确证和定量测定。     

n—Butyl Pyridinium Nitrate as a Reusable Ionic Liquid Medium for Knoevenagel Condensation

The Knoevenagel condensation of carbonyl substrates with active methylenecompounds proceeds smoothly with ammonium acetate as catalyst in n-butyl pyridinium nitrate to afford the desired products of good purity in moderate yields.     

固相萃取-高效液相色谱法测定浓缩苹果汁中的多菌灵残留量

报道了固相萃取-高效液相色谱法测定浓缩苹果汁中多菌灵残留量的方法.样品经适量水稀释后,C18固相萃取柱提取净化,用V(甲醇)∶V(二氯甲烷)=1∶1淋洗,HPLC法测定.在添加水平为0.10,0.50,2.0 mg/kg时,多菌灵的回收率在92.6%～108.3%之间;RSD＜3% (n=6),检出限为0.02 mg/kg,该方法的测定结果满足农药残留量的检测要求.