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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.
建立了以香烟过滤嘴纤维作吸附剂,在线固相萃取-高效液相色谱(SPE—HPLC)测定水中邻硝基苯甲酸、对硝基苯胺、邻硝基苯酚、3-氯硝基苯四种硝基类化合物的方法。邻硝基苯甲酸、对硝基苯胺、邻硝基苯酚、3-氯硝基苯分别在0.006~4.80、0.003~2.40、0.002~1.60、0.002~1.60mg/L范围内峰面积与浓度呈线性关系,相关系数分别为0.9994、0.9996、0.9997和0.9996;检出限(S/N=3)分别为1.0、0.8、0.6,0.6μg/L;富集倍数分别为28.2、176.6、172.1、153.3。该法用于河水中四种硝基类化合物的测定,回收率为85.41%~116.44%,相对标准偏差在1.1%~5.4%范围内。  相似文献   

3.
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   

4.
1051例儿童头发中微量元素的研究和相关性分析   总被引:2,自引:0,他引:2  
为探讨儿童头发中 6种元素之间的相关性关系 ,应用电感耦合高频等离子体发射光谱仪(ICP -AES)测定了 6种元素的含量 ,并用SAS或SPSS软件 ,经计算机处理。结果表明 ,1 0 5 1例儿童头发中Zn、Fe、Cu、Ca、Mn和Pb含量分别为 (91 96± 2 0 0 5 )× 1 0 -6,(3 1 3 6± 5 5 2 )× 1 0 -6,(1 1 78± 2 69)× 1 0 -6,(677 3 8± 1 0 8 94)× 1 0 -6,(2 73± 1 0 4)× 1 0 -6和 (1 1 0 1± 3 62 )× 1 0 -6。儿童头发中 ,Zn与Pb含量呈非常显著负相关 ,P <0 0 1 ;Cu与Mn和Pb呈非常显著正相关 ,P <0 0 1 ;Ca与Pb呈非常显著正相关 (P =0 0 0 1 ) ;Mn与Pb呈非常显著正相关 ,P <0 0 1。  相似文献   

5.
父母职业对幼儿头发中微量元素水平的影响   总被引:1,自引:0,他引:1  
测定了深圳市父母不同职业的 894名 1~ 7岁幼儿头发中的Zn、Cu、Fe、Ca、Mn、Pb的含量。结果表明 ,父母为干部与父母为工人的幼儿头发中的Fe有显著性差异 (P <0 0 5) ,其含量分别为 (2 9 2± 4 9)× 10 -6和 (30 0± 5 6 )× 10 -6;父母为干部与父母为工人的幼儿头发中的Mn有非常显著性差异 (P <0 0 0 1) ,其含量分别为 (1 7± 0 7)× 10 -6和 (1 9± 1 0 )× 10 -6;父母为干部与父母为工人的幼儿头发中的Pb有显著性差异 (P <0 0 5) ,其含量分别为 (12 3±7 6 )× 10 -6和 (13 2± 7 5)× 10 -6。本文还列出了幼儿头发中元素的含量比较图。  相似文献   

6.
溶剂萃取原子吸收光谱法测定头蜡中铅铬镉镍钴   总被引:5,自引:0,他引:5  
用高压溶样弹将头蜡用HNO3-H2O2溶解,经0.0500mol/L 8-羟基喹啉体氯仿溶液萃取,用原子吸收光谱法测定痕量铅、铬、镉、镍和钴。方法回收率分别为99.0%、99.5%、96.0%、102%和98.5%,RSD分别为2.9%、3.0%、4.1%、3.8%和2.0%。方法可应用于出口头蜡检测。  相似文献   

7.
采用催化极谱方法分析了 98例 (糖尿病人 47例 ,对照组健康人 5 1例 )头发样品中的微量元素铬 (Cr)、锰 (Mn)、铁 (Fe)、铜 (Cu)、锌 (Zn)、硒 (Se)和宏量元素钙 (Ca)、镁 (Mg)含量水平。结果显示 ,糖尿病人头发样品中的Cr( 0 99± 0 75 )× 1 0 - 6 、Mn( 1 3 0± 0 90 )× 1 0 - 6 和Cu( 8 5 0± 1 40 )× 1 0 - 6 分别显著低于对照组头发样品中的Cr( 1 5 5± 0 97)× 1 0 - 6 、Mn( 2 3 0± 1 60 )×1 0 - 6 和Cu( 1 0 40± 2 90 )× 1 0 - 6 ,Cr、Mn、Cu的显著性水平分别为P =0 0 0 1 ,P <0 0 0 1和P <0 0 0 1。而糖尿病人头发样品中的Fe( 1 9 0 0± 9 0 0 )× 1 0 - 6 ,则显著高于对照组头发样品中的Fe( 1 6 0 0± 8 0 0 )× 1 0 - 6 ,其显著性水平P为 0 0 2 3。但糖尿病人与健康人头发样品中的Zn、Se、Ca和Mg含量水平之间的差别并不显著。这些结果与其他一些研究所得的结论基本一致。  相似文献   

8.
为调查清远市幼儿发铅水平和相关因素 ,对 96名年龄在 2~ 3岁的健康幼儿进行了发铅检测 ,并根据居住环境、父母职业、饮食习惯进行了分组比较。结果表明 ,居住于市内组发铅(8 1 2± 1 1 1 )× 1 0 - 6 高于居住于市外组 (7 3 5± 0 5 5 )× 1 0 - 6 ,P <0 0 1 ,父母职业可能接触铅组(8 1 9± 1 0 5 )× 1 0 - 6 高于父母职业不接触铅组 (7 41± 0 62 )× 1 0 - 6 ,P <0 0 0 1。喝牛奶组 (7 2 7± 0 5 0 )× 1 0 - 6 低于不喝牛奶组 (8 2 7± 0 99)× 1 0 - 6 ,P <0 0 0 1。可见居住环境、父母职业、饮食习惯的影响发铅含量  相似文献   

9.
采用顶空气相色谱法测定地塞米松磷酸钠中甲醇、丙酮等有机溶剂的残留量。最佳平衡温度为50℃,最佳平衡时间为70min,甲醇、丙酮在3min内分离良好,线性相关系数分别为0、9996、0.9997,平均回收率分别为102.2%、101.3%,测定结果的相对标:住偏差分别为1.5%、1.8%(n=5)。  相似文献   

10.
1000例幼儿头发中微量元素含量分析   总被引:1,自引:0,他引:1  
测定了 1 0 0 0例儿童头发中 6种元素含量。结果表明 ,本组儿童头发中的Zn为 ( 82 1 4±1 9 1 0 )× 1 0 - 6 ,Ca为 ( 5 1 1 5 5± 93 5 5 )× 1 0 - 6 ,Mn为 ( 1 80± 0 86)× 1 0 - 6 ,均低于国内报道的正常儿童发中元素含量低限值 (Zn 87 75× 1 0 - 6 ,Ca 61 3 2 5× 1 0 - 6 ,Mn 2 1 4× 1 0 - 6 )。本组儿童发Pb平均值为 ( 1 2 81± 7 43 )× 1 0 - 6 ,显著高于国内报道的正常儿童发Pb高限值 ( 1 0 43× 1 0 - 6 )。  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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