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1.
戈早川  周建明 《分析化学》2004,32(1):99-101
以2%CPC-醋酸乙酯(9:1)胶束溶液为展开剂,在聚酰胺薄膜上成功地分离了小檗碱、巴马汀和药根碱。以345nm为测定波长,550nm为参比波长进行扫描测定,建立了一种新的同时测定黄连及其制剂中小檗碱、巴马汀和药根碱的胶束薄层扫描法。小檗碱、巴马汀和药根碱的线性范围分别为0.2—2.4、0.1—1.0和0.1—1.0μg;回收率分别为97.7%-99.4%、101.7%~102.6%和96.7%-97.8%;相对标准偏差分别为1.4%-1.7%、1.9%-2.7%和1.8%-2.2%。  相似文献   

2.
采用王水分解试样,原子荧光光谱法(AFS)测定了出土文物体及周围土壤中的砷、汞。结果表明,该测定的相对标准偏差分别为:0.8%~1.0%;1.4%~1.5%。方法回收率分别为:97.0%~102.0%;98.0%~104.0%。该法具有简便、快速、准确等优点,结果令人满意。  相似文献   

3.
原子荧光法测定食品中砷和硒   总被引:29,自引:1,他引:28  
采用氢化物发生-原子荧光光度法测定食品中砷和硒。砷和硒的相对标准偏差分别为1.17%和1.19%,检出限分别为0.28和0.40ng·ml-1。线性范围为0~100ng·ml-1,砷和硒的相关系数分别为0.9998和0.9999。砷和硒的回收率分别为95.8%~105.4%和98.5%~103.5%。  相似文献   

4.
以N,N-二甲基甲酰胺(DMF)为溶剂,丁酮为内标,采用PV-101毛细管色谱柱 (30 m×0.22 mm),氢火焰离子化检测器,建立兰索拉唑中五种有机溶剂甲醇、乙醇、丙酮、二氯甲烷、乙酸乙酯残留量的定量分析方法。五种有机溶剂检出限分别为0.002 4%,0.002 4%, 0.001 2%,0.000 6%,0.000 6%;在10-1000 mg·L-1浓度范围内,各组分线性关系良好;对应的平均回收率分别为100.8%±3.6%,102.1%±2.3%,99.97%±4.1%,99.63%±2.7%, 102.3%±3.5%。  相似文献   

5.
抑制型离子色谱法测定白酒中的F-、Cl-、NO2-、H2 PO4-、NO3-   总被引:3,自引:0,他引:3  
用抑制型离子色谱法测定白酒中的F^-、Cl^-、NO2^-、H2PO4^-、NO3^-。流动相为4mmol/LNa2CO3—3 mmol/LNaHCO3混合溶液,流速为1.5mL/min,进样量为0、5mL,在最佳色谱条件下,5种无机阴离子10min内实现基线分离。F^-、Cl^-、NO2^-、H2PO4^_、NO3^-的检出限分别为0、008、0.012、0、030、0.068、0.077mg/L。测定结果的相对标准偏差分别为1.86%、1.30%、2.06%、1.82%、1.50%,回收率分别为108.0%、94.0%、101.0%、98.7%、94.4%。  相似文献   

6.
报道了用直接消解法处理蜂蜜,在选定光谱条件下,用火争原子吸收分光光度计测定其中的钙和锌,与湿法,干法消解处理的试样相比较,该法操作简单,结果令人满意,加标回收率钙为99-101.9%。锌为98.8%-105%,相对标准偏差钙为4.4%-5.9%,锌为2.1%-3.8%检出限钙为0.138ug.mL^-1,锌为0.084ug.mL^-1。  相似文献   

7.
苯胺及取代的苯胺和Meldrum’s acid在固相无催化剂条件下反应,合成了丙二酸单苯酰胺(1a-1f),收率81.0%~92.2%.化合物1a-1f在Eaton试剂(五氧化二磷+甲基磺酸)或多聚磷酸为环化试剂的条件下发生Friedel—Crafts分子内环化反应,以63.2%~93.8%和56.5%~81.3%的收率方便地得到4-羟基喹啉-2-酮衍生物(2a-2f).产物的结构通过IR,^1H NMR和元素分析得以证实.  相似文献   

8.
30%毒死蜱微乳剂在甘蓝及土壤中的残留动态研究   总被引:1,自引:0,他引:1  
利用气相色谱(配FPD检测器)分析测定了30%毒死蜱微乳剂在甘蓝和土壤中的残留消解动态和最终残留量。毒死蜱色谱峰面积与质量浓度在0.01~0.5mg/L范围内呈良好的线性关系,相关系数,为0.9992。甘蓝和土壤中毒死蜱的最低检出浓度均为0.005mg/kg,在0.01,0.02,0.1mg/kg3个添加水平下,甘蓝及土壤中毒死蜱的平均回收率分别为80.1%~96.4%和82.1%-98.7%,变异系数分别为1.2%~5.0%和2.5%-3-3%(n=10)。残留消解动态的结果表明:毒死蜱在甘蓝中的半衰期为5.8~10.5d,在土壤中的半衰期为8.0~10.5d。毒死蜱在收获期甘蓝及土壤中最终残留量均低于我国规定的限量值(1.0mg/kg)。  相似文献   

9.
固相微萃取-气相色谱/质谱法分析白胡椒粉的风味成分   总被引:1,自引:0,他引:1  
采用固相微萃取采集白胡椒粉的挥发性成分,用色谱/质谱法分析鉴定,并用总离子流色谱峰的峰面积进行归一化定量分析其风味成分,鉴定出石竹烯(20.88%),1-甲氧基-4-(2-丙烯基)苯(20.57%),β-水芹烯(15.27%),3-蒈烯(14.56%),1-甲基-3-异丙基苯(3.62%),β-蒎烯(2.69%),芳樟醇(2.69%),香叶烯(2.36%),墨榄香烯(2.10%),胡椒烯(1.32%)等48种化合物。  相似文献   

10.
李克昌  张恒彬  刘佳  曹学静  张玉敏 《分析化学》2005,33(11):1580-1582
建立了以磷酸氢二钾-磷酸盐缓冲溶液中添加甲醇为流动相,以反相高效液相色谱同时测定吡啶、2-氨基吡啶、2-甲基吡啶和2-吡啶甲酸的新方法。在流动相为甲醇-0.1mol/L磷酸氢二钾和磷酸缓冲溶液、pH为6.0的最佳条件下,吡啶、2-氨基吡啶、2-甲基吡啶和2-吡啶甲酸的加标回收率分别为98.2%~102.1%、99.1%~101.3%、97.8%~100.7%和99.1%~102.4%;线性范围分别为20~980、18~913、19~943和18~902mg/L;检出限分别为2.0、1.8、1.9和1.8mg/L。本法可同时测定电氧化2一甲基吡啶过程中电解液。  相似文献   

11.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

12.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

13.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

14.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

15.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

16.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.  相似文献   

17.
用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.  相似文献   

18.
19.
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).  相似文献   

20.
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.  相似文献   

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