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1.
对磺酸基苯亚甲基若丹宁固相萃取光度法测定水中的汞   总被引:13,自引:0,他引:13  
研究了对磺酸基苯基亚甲基若丹宁(SBDR)与汞的显色反应,在pH4.0的HAc NaAc缓冲介质中,吐温 80存在下,SBDR与汞反应生成2∶1稳定络合物,该络合物可被WatersPorapak Sep Park C18固相萃取小柱萃取,用乙醇洗脱后在乙醇介质中λmax=520nm,可用分光光度法测定,体系ε=1.16×105L/mol·cm。汞含量在0μg/mL~1.5μg/mL内符合比尔定律,方法可用于水样中汞含量的测定。  相似文献   

2.
合成了新试剂对磺酸基苯亚甲基硫代若丹宁(SBDTR),并用红外光谱、核磁共振氢谱和元素分析鉴定其结构。研究了SBDTR与汞的显色反应。在pH3.5的HAc NaAc缓冲介质中,吐温 80存在下,SBDTR与汞反应生成2∶1稳定络合物。该络合物可用WatersSep ParkC18固相萃取柱萃取,用乙醇洗脱后,在乙醇介质中用分光光度法测定,体系摩尔吸光系数为8.36×104L·mol-1·cm-1。汞含量在0~4μg/mL内符合比耳定律。本方法可用于烟草添加剂中汞含量的测定,结果满意。  相似文献   

3.
新型若丹宁试剂光度法测定镍的研究   总被引:5,自引:0,他引:5  
利用合成的新型试剂3 对氟苯基 5 (2′ 羧基苯偶氮)若丹宁与金属镍进行显色反应,发现在表面活性剂存在下,新型若丹宁显色剂与镍有较灵敏的反应,镍量在0~25μg/10ml范围内符合比耳定律,其表观摩尔吸光系数为2.3×104L·mol-1·cm-1,可用于水及茶叶中镍的测定。  相似文献   

4.
新试剂SBDR固相萃取光度法测定烟草中汞   总被引:3,自引:0,他引:3  
在pH为3.5的HOAc-NaOAc缓冲介质中,吐温-80存在下,对磺酸基苯基亚甲基若丹宁(SBDR)与汞反应生成2∶1稳定络合物,该络合物可被Waters Sep-Pak-C18固相萃取小柱萃取,小柱上富集的络合物用1.0 mL无水乙醇洗脱后在乙醇介质中,于其吸收峰550 nm处用1 cm微量比色皿测定吸光度。该显色体系的表观摩尔吸光系数ε=1.05×105L.mol-1.cm-1。汞含量在0~4μg/50 mL内符合比耳定律,方法用于烟草中汞含量的测定,测得RSD(n=7)小于2.5%,回收率在97%~103%之间,测得结果与AAS法测得结果一致。  相似文献   

5.
新试剂5-(3-甲基-2-吡啶)-亚甲基若丹宁与钯显色反应研究   总被引:12,自引:0,他引:12  
合成了新试剂5-(3-甲基-2-吡啶)-亚甲基若丹宁(MPMR),研究了其与钯的显色反应在pH值为4.0-6.5介质中,吐温-80和Triton X-100混合表面活性剂存在下.MPMR和Pd2+生成2∶1配合物,λmax=435nm,ε=6.15×104L·mol-1·cm-1。钯含量在0-3μg/25ml内符合比耳定律,方法用于钯催化剂中钯的测定,结果满意。  相似文献   

6.
研究了对磺酸基苯亚甲基若丹宁(SBZRN)与铜的显色反应,在pH为5.0的HOAc NaOAc缓冲介质中,SBZRN与铜反应生成2∶1稳定络合物,λmax=510nm,ε=7.48×104L·mol-1·cm-1。铜含量在0~10μg/25ml内符合比耳定律,方法用于铝合金中铜含量的测定,结果满意。  相似文献   

7.
合成了新型试剂3 对甲苯基 5 (2′ 胂酸基苯偶氮)若丹宁,研究了在表面活性剂存在下试剂与镍的显色反应,建立了光度法测定镍的新方法,其表观摩尔吸光系数为2.6×104L·mol-1·cm-1,镍量在0~20μg/10mL范围内符合比耳定律,可用于水及茶叶中镍的测定。  相似文献   

8.
合成了新显色剂对硝基苯酚偶氮罗丹宁 [5 (5 硝基 2 羟基苯偶氮 )罗丹宁 ],并研究了与Au(Ⅲ )的显色反应。在H3PO4 介质及在混合表面活性剂OP +CTMAB存在下 ,Au(Ⅲ )与该试剂形成 1∶5的橙色络合物 ,最大吸收峰λmax=4 80nm ,摩尔吸光系数ε =2 .0× 10 6 L·mol- 1·cm- 1。Au(Ⅲ )含量在 0~ 1.2 μg/2 5ml内符合比耳定律。方法的灵敏度高 ,选择性好 ,直接用于含Au(Ⅲ )废水中金的测定 ,结果满意  相似文献   

9.
合成了新试剂乙氧基苯并噻唑重氮氨基偶氮苯 ,并研究了它与汞的显色反应。在TritonX 1 0 0存在下 ,pH 1 0 4~ 1 1 0的Na2 B4O7 NaOH缓冲溶液中 ,试剂与汞生成 1∶1型红色配合物 ,最大吸收波长为 5 1 0nm ,其表观摩尔吸光系数为 1 1 6× 1 0 5L·mol- 1 ·cm- 1 。Hg2 +的浓度在 0 μg/L~ 6 0 0 μg/L范围内符合比尔定律。采用标准加入回收法测定了实验室废水中的汞含量。  相似文献   

10.
5-碘[杯(4)芳烃偶氮]氨基喹啉光度法测钴   总被引:5,自引:0,他引:5  
黄章杰  胡秋芬  杨光宇  尹家元 《分析化学》2003,31(12):1465-1467
合成了新试剂 5 碘 [杯 (4 )芳烃偶氮 ]氨基喹啉 (ICAQ) ,并研究了该试剂与钴显色反应条件。在弱碱性介质中 ,不加任何辅助试剂 ,ICAQ与钴发生显色反应 ,生成 1∶1稳定络合物。λmax=61 5nm ,ε=4.78× 1 0 5L·mol- 1 ·cm- 1 ;钴含量在 1 0~ 1 3 0 μg L内符合比尔定律。方法用于维生素B1 2 、茶叶、水样中微量钴的测定 ,结果令人满意。  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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