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固相微萃取-气相色谱法分析水中痕量1-萘酚 总被引:4,自引:1,他引:3
利用固相微萃取(SPME)-气相色谱法(GC)分析了水中前量的1-萘酚。对于SPME萃取头,溶液介质条件、吸附和解吸时间进行了研究。结果表明,PA_85萃取头对于水中1-萘酚的富集效果最佳。而无机盐氯化钠的加入和降低PH值可以明显地改善萃取效果。在优化后的条件下,SPME-GC方法对于水中1-萘酚的检测限可达0.5μg/L,分析过程中标准偏差均小于4%。 相似文献
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锑(锡)—Ferron—Se(Ⅳ)络合吸附催化波研究及应用 总被引:1,自引:1,他引:1
在pH1.8的H2SO4-NaAc缓冲溶液中,用单扫示波极谱法,Sb(Ⅲ)或者(Sn(Ⅳ)-7-碘-8-羟基喹啉-5-磺酸-Se(Ⅳ)体系可产生灵敏的络合吸附催化波。锑、锡浓度分别在0.4~200μg/L和0.8~180μg/L范围内与峰高呈线性关系,检测限分别为0.2μg/L和0.4μg/L,并用于工业废水,地下水和天然水中痕量锑和锡的测定,同时对电话性络合物的组成,极谱波的性质和电极过程机理也 相似文献
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在pH1.8的H_2SO_4-NaAc缓冲溶液中,用单扫示波极谱法,Sb(Ⅲ)或者Sn(Ⅳ)-7-碘-8-羟基喹啉-5-磺酸-Se(Ⅳ)体系可产生灵敏的络合吸附催化波。锑、锡浓度分别在0.4~200μg/L和0.8~180μg/L范围内与峰高呈线性关系,检测限分别为0.2μg/L和0.4μg/L,并用于工业废水、地下水和天然水中痕量锑和锡的测定。同时对电活性络合物的组成、极谱波的性质和电极过程机理也作了讨论和研究。 相似文献
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参照美国EPA525.1方法,C18-固相萃取膜萃取饮用水中的有机物,利用GC/MS法鉴定多环芳烃(PAHS),使用16种多环芳烃混合标准样绘制标准曲线,以内标法对PAHS进行定量分析。采用本方法某水厂经过深度处理后的出厂水中的7种多环芳烃的含量,PAHS的平均回收率为94.0-97.7%。检测限为0.001μg/L。 相似文献
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气相色谱/质谱法测定大鼠脑中5-羟色胺的含量 总被引:4,自引:1,他引:3
采用气相色谱/质谱法(GC/MS)测定了正常大鼠和服药大鼠脑组织中5-羟色胺(5-HT)的浓度。大鼠脑组织制成匀浆后,先将5-HT酰化,酰化物经乙酸乙酯提取后,再经七氟丁酸酐衍生化,用GC/MS测定。MS采用电子捕获负离子化学电离(ECNICI)模式。方法的线性范围为0.50~50.0μg/L,回归方程为Y=0.1348X-0.07995(r=0.9996);平均回收率为98.2%±3.8%(n=10);检测限为0.5μg/L;相对标准偏差小于10%。 相似文献
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丁基罗丹明B—钼酸盐光度法连续测定铈和钪 总被引:4,自引:0,他引:4
在聚乙烯醇(PVA)存在下,丁基罗丹明B(BRB)分别与铈钼、钪钼杂多酸络阴离子形成离子缔合物,其最大吸收均位于570nm,表面摩尔吸光度分别为εCe=3.96×10^6L.mol^-1.cm^-1,εSc=4.71×10^5L.mol^-1.cm^-1,服从比耳定律范围分别为0-24μg/L Ce和0-60μg/LSc,测定极限为Ce1.0μg/L(n=12)和Sc1.9μg/L(n=10),对 相似文献
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Uroš Grošelj Mojca Žorž Amalija Golobič Branko Stanovnik Jurij Svete 《Tetrahedron》2013,69(52):11092-11108
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
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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
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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
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Shashikant U. Dighe Surya K. Samanta Shivalinga Kolle Sanjay Batra 《Tetrahedron》2017,73(17):2455-2467
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
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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
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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
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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
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Jona Mirnik Eva Pušavec Kirar Sebastijan Ričko Uroš Grošelj Amalija Golobič Franc Požgan Bogdan Štefane Jurij Svete 《Tetrahedron》2017,73(24):3329-3337
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
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George E. Magoulas Thomas Garnelis Constantinos M. Athanassopoulos Dionissios Papaioannou George Mattheolabakis Konstantinos Avgoustakis Dimitra Hadjipavlou-Litina 《Tetrahedron》2012,68(35):7041-7049
(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