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1.
聚吡咯碳糊电极的研制及应用   总被引:6,自引:0,他引:6  
杨继生 《分析化学》1998,26(7):847-849
研制了聚吡咯电极,探讨了该电极的性能和实用性,实验结果表明,该电极可用于伏安法快速测定L-抗坏血酸,在0.1mol/LKNO3底液中,线性范围为1.0×10^-11~9.0×10^-9mol/L检测限为5.0×10^-12mol/L,电极具有具有良好的重现性和高选择性,响应迅速,使用寿命3个月以上。  相似文献   

2.
徐达峰  黄超伦 《分析化学》1994,22(6):596-598
本以石墨棒为导电基体,以硅钨酸,林可霉素为电活性和的制成了全固态林可霉素离子选择电极。所制电极在1.0×10^-1-5.0×10^-5mol/L浓度范围内有线性响应,斜率为58.3mV/pC,检测下限为2.5×10^-5mol/L。电极响应迅速,具有良好的稳定性,可用于林可霉素含量的快速测定。  相似文献   

3.
本文利用肝素与某些金属离子之间强烈的亲和作用,设计成了一种新型的伏安传感器,这处用肝素修饰的玻碳电极被用于前量铜的阳极溶出伏安测定。该电极制作简便,具有较好的重现性,选择性和较高的灵敏度,本方法测定铜的线性范围为2.0×10^-8mol/L~1.0×10^-6mol/L,检测下限为1.0×10^-9mol/L,同一支修饰电极平行测定10次的相对标准偏差是3.20%。  相似文献   

4.
乙醇酸菠菜组织电极和马兰组织电极的研究   总被引:1,自引:0,他引:1  
马全红  张晓华 《分析化学》1994,22(7):668-671
分别以菠菜和马兰叶为生物催化材料,将其叶浆组织与氧电极相结合,首次制成乙醇酸电极,本研究了这两种电极的响应性能。菠菜组织电极线性范围为5.0×10^-6-1.0^10^-4mol/L;响应时间为3min;寿命为10天,马兰组织电极线性范围为2.0×10^-6-1.0×10^-4mol/L;响应时间为3min;寿命至少30天。这两种电极对底物乙醇酸钠皆有良好的选择性。  相似文献   

5.
顾慰中 《分析化学》1997,25(3):308-310
报道了复MoS62-4在铜表面形成不溶性族合物膜的性质,研制了一种簇合物膜亚硫酸根离子选择电极。电极对HSO^-3的线性响应范围为1×10^-4-1×10^-1mol/L;检测限为8×10^-5mol/L;响应斜度为58.5mV/dec;适宜的pH范围为9-10。  相似文献   

6.
铅基磷酸铅化学修饰电极的研究   总被引:3,自引:0,他引:3  
孙玉堂  刘强 《分析化学》1995,23(11):1274-1276
本研制了铅基磷酸铅化学饰电极,并研究了该CME的性能。实验发现,该CME是一种磷酸根离子敏感电极。电极对磷酸盐有类能斯特响应,在PH4.0和6.0下,其线性范围分别为1×10^-3-1×10^-1和1×10^-4-1×10^-2mol/L磷酸盐,电极响应斜率为23-27mV/dec.电极有较好的稳定性重现性,可望用于磷酸盐的实际分析。  相似文献   

7.
用循环伏安法研究了制备掺杂磷钼根离子聚吡咯化学修饰电极的条件,对其性能进行了电化学表征,电极对磷钼酸根(PMo12O^3-40)离子具有选择性电位响应,线性范围为1.0×10^-6~1.0×10^-3mol/L。斜率约为50mV,测定了电极的有关性能参数。电极可用于无机磷含量的检测。  相似文献   

8.
聚吡咯水杨酸修饰电极的电化学行为及水杨酸含量测定   总被引:10,自引:0,他引:10  
李春光  崔刚 《分析化学》1994,22(9):922-924
本用电化学方法制备了聚吡咯-水杨酸修饰电极;并进行了电化学行为的研究,经电化学处理该是电极对水杨酸根具有选择性响应,响应线性范围在1.0×10^-^5-1.0×10^-^3mol/L之间。电极斜率为40mV/pC,该电极具有较好的稳定性,响应时间在180-300s之间;电极寿命可达60d。  相似文献   

9.
醋酸纤维膜固定过氧化氢酶电极的研究   总被引:1,自引:0,他引:1  
刘树庭  林朝晖 《分析化学》1994,22(10):998-1001
本将过氧化氢酶与经活化处理的醋酸纤维膜共价固定,并与氧电极偶合,研制成静态和流通二种过氧化氢生物电极。研究了醋酸纤维膜的活化、酶的固定化、测试介质等有关的实验条件和参数。测得静态和流通二种电极响应的线性范围分别为6.7×10^-5 ̄2.0×10^-3mol/L和1.3×10^-4 ̄1.0×10^-3mol/L。将电极用于实际试样中的回收率测定时,获得了较好的结果。  相似文献   

10.
聚氯乙烯膜奎宁选择电极的研制与应用   总被引:4,自引:0,他引:4  
李东辉  丁杨栋 《分析化学》1995,23(11):1271-1273
本报道了一种以奎宁溴汞酸盐为电活性物的PVC膜奎宁选择电极,其线性响应范围为1.0×10^-2-1.0×10^-6mol/L;级差58±1mV;检测限为8.2×10^-7mol/L。以此电极测定奎宁的含量,方法简单、快速、结果与药典法相符。  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
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   

14.
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   

15.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

16.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

17.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

18.
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   

19.
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   

20.
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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