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1.
铜铂微粒修饰微电极测定一氧化氮   总被引:3,自引:0,他引:3  
鲜跃仲  朱民  张文  薛建  金利通 《分析化学》1999,27(10):1168-1171
详细报道了金属铜,铂微粒微电极用于NO的检测,该修饰电极对NO具有催化氧化作用,当NO浓度在8.2×10^-8-4.5×10^-6mol/L内,浓度与峰电流呈线性关系,相关系数为0.997。  相似文献   

2.
聚N,N-双水杨醛乙二胺合铁一氧化氮超微传感器的研究   总被引:4,自引:0,他引:4  
报道了电化学聚合N,N-双水杨酸乙二胺合铁[p-Fe(salen)]一氧化氮(NO)超微传 感器的制备、NO的响应及机理研究.实验发现,用电化学聚合的方法制备的 p-Fe(salen)超微传感器对 NO的检测有高的灵敏度和好的选择性. NO的浓度在 7. 2× 10-8~4. 4× 10-6 mol/L范围内,氧化电流与浓度呈线性关系;线性相关系数为0.9996,检测限达3.6×10-8 mol/L;生物体中常见的物质如抗坏血酸、尿酸、儿茶酚胺类代谢产物、NO的氧化产物NO-2 等不干扰测定.所研制的传感器可用于NO的在体分析.  相似文献   

3.
以四磺基铁酞菁(FeTSPe)作为过氧化物模拟酶催化H2O2与L-酪氨酸的荧光反应,建立了测定宽含量范围的H2O2及葡萄糖的方法。该法的线性范围为0.0-8.0×10^5mol/L,H2O2及0.0 ̄2.0×10^-4mol/L葡萄糖,检测限分别为5.0×10^-8mol/L及6.0×10^-6mol/L,将该经酶催化反应偶联,测定人血清中葡萄糖的含量,取得了满意的结果。  相似文献   

4.
通过电化学聚合法制备了聚N,N-双水杨醛乙二胺合钴[polyCo(Salen)]修饰超微电极,研究了该修饰电极的电催化性质及其在一氧化氮(NO)测定中的应用.实验结果表明,polyCo(Salen)修饰超微电极对NO的测定有高的灵敏度,NO的浓度在2.0×10-8~2.8×10-6mol/L范围内,电流与浓度呈良好的线性关系,线性相关系数为0.9998,检出限为1.0×10-8mol/L;该电极进一步修饰Nafion后,生物体中常见的物质如抗坏血酸、儿茶酚胺类神经递质的代谢物、NO的氧化产物NO-2等不干扰测定.本传感器可以满足NO在体分析的需要.  相似文献   

5.
头孢拉定的电化学行为   总被引:11,自引:0,他引:11  
曾泳淮  马红艳 《分析化学》1997,25(9):1006-1009
头孢拉定在NoOH溶液中降解后,于0.3mol/L NaOH底液中有一灵敏的导数还原峰。电峰位为-0.84V左右,峰电流ip与头孢拉定浓度在2.0*10^-8-5.0*10^T-6mol/L范围内呈线性关系,检测限为5.0*10^-9mol/L。  相似文献   

6.
详细报道了Nafion-聚[N′,N″-(1,3-丙二亚甲基)双(1,2-苯二氨基)-N,N′,N″,N]合镍[PolyNi(Ⅱ)L]修饰微铂电极的制备及性质.实验表明,该修饰电极对NO有较高的灵敏度和选择性.当NO的浓度在2.0×10-7~1.6×10-5mol/L范围内峰电流与NO的浓度呈线性关系,相关系数r=0.994.用于血液中NO的检测,效果良好.  相似文献   

7.
杨志 《分析化学》1998,26(5):542-544
在金电极上,用电化学方法将单缺位Dawson型磷钨杂多酸盐a2-K10P2W17O6115H2O的阴离子(P2W17)掺杂到聚吡咯(PPy)薄膜中,制成PPy/P2W17/Au的H2O2传感器。研究了它对 H2O2电还原过程的催化机理.其 ipe与 CH2O2在 6.0× 10-5~8. 8×10-4 mol/L和8.8×10-4~6.0×10-3mol/L范围内呈良好的线性关系,检测下限为4.0×10-5mol/L。用于模拟水样中H2O2的测定,结果较满意.  相似文献   

8.
极谱催化波法测定黄连素   总被引:5,自引:0,他引:5  
宋俊峰  何盈盈  过玮 《分析化学》2000,28(12):1538-1541
基于黄连素在过氧化氢存在下产生的极谱催化波,拟定了测定黄连素的新方法。在8.0×10-2mol/LNa2B4O7-Na2CO3(pH9.4±0.4)-4.0×10-3mol/LH2O2底液中,催化波峰电流与黄连素浓度在 1.0 × 10-8~ 3.0 × 10-7mol/L范围内呈线性关系。催化波的灵敏度比相应黄连素还原波高25倍。  相似文献   

9.
在0.01mol/LNH.H2O-NH4Cl和3.0×10^-5mol/L安息香缩氨基硫脲体系中,钴产生一灵敏的还原波,其峰电位是-0.94V(vs.SCE),峰电流与钴的浓度在2.0×10-8-1.0×10^-6mol/L范围内成直线关系,检测限为5.0×10^-9mol/L,该法测定水中痕量钴结果令人满意。  相似文献   

10.
在0.2mol/LNaOH-0.04mol/LH3PO4-0.02mol/L(NH4)2SO4-0.04mol/LCH3COOH溶液中,精氨酸(Arg)在苯甲醛存在下产生一灵敏的吸附波。实验证明电活性物质为α-苯亚甲基精氨酸,其电极反应机理是分子内α->C=N基团被还原为亚胺。用该吸附波可在1×10(-3)~2×10(-6)mol/L范围内分析蛋白质中的Arg。  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.
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   

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.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

16.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

17.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

18.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

19.
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   

20.
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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