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排序方式: 共有580条查询结果,搜索用时 15 毫秒
1.
K. Volkan
zdokur 《Electroanalysis》2020,32(3):489-495
Copper oxide decorated multi‐walled carbon nanotube (MWCNT) modified glassy carbon electrode (GCE) was prepared for determination of isoniazid (INZ) in various matrices. The electrochemical behavior of INZ was tested with the aid of Cyclic Voltammetry (CV) and quantitative experiments were performed by using Linear Sweep Voltammetry (LSV). Morphological and structural characterization of the modified electrode was performed by utilizing Scanning Electron Microscopy (SEM), X‐Ray Photoelectron Spectroscopy (XPS) while electrochemical characterization was performed by using CV and Electrochemical Impedance spectroscopy (EIS). The proposed sensor exhibited well defined anodic peak at 0.30 V for INZ at pH 6.0 medium. Under the optimum conditions, a linear relation between INZ concentration and peak current was observed in the range of 2.0×10?7 to 5.0×10?5 M. Limit of detection was calculated as 1.0×10?8 M and repeatability and accuracy was found as 5.60 % and 91.0 % for 5.0 10?7 M INZ by using 3 successive measurement, respectively. Then, the analytic performance of the electrode developed was tested by analyzing commercial tablets, artificial human serum and urine samples. The results indicated that satisfactory recoveries was observed for all issue. 相似文献
2.
Paul du Bois-Reymond 《Mathematische Annalen》1879,15(3-4):564-576
Ohne Zusammenfassung 相似文献
3.
Reaction of acetylene dicarboxaldehyde monoacetal with substituted Meldrum’s acid leads good yields in 2-pyranones-4-carboxaldehydes substituted in position 3. 相似文献
4.
Efficient synthesis of ferrocenylenones using a Friedel-Crafts acylation reaction is described. Acryloyl, methacryloyl, crotonoyl, cinnamoyl, and β-methylcrotonoyl chlorides react with ferrocene in the presence of a Lewis acid (EtAlCl2 or EtAlCl2-Me3Al) to give the corresponding ferrocenylenones (acryloyl, methacryloyl, crotonoyl, cinnamoyl, and methylcrotonoylferrocenes) in good isolated yields. Besides ferrocenylenones, chloroactylferrocene is also synthesised by this method. 相似文献
5.
Paul du Bois-Reymond 《Mathematische Annalen》1882,20(1):122-124
Ohne ZusammenfassungAbgedruckt aus den Sitzungsberichten der math.-phys. Classe der k. b. Akadem. d. Wiss. zu München. 相似文献
6.
A study of the electrochemical reduction of the mesotrione pesticide on a hanging mercury drop electrode (HMDE) was performed
as a basis for the development of a sensitive analytical method for natural samples. The electrochemical characteristics of
herbicide mesotrione dissolved in a phosphate buffer (pH 7.0) have been determined by means of electrochemical techniques
such as cyclic voltammetry (CV) and differential pulse voltammetry (DPV) over a wide range of pH from 2.0 to 10.0. The experimental
parameters, such as electrolyte type and its pH, pulse amplitude, and scan rate were optimized. The method was applied to
the determination of the pesticide in a spiked soil samples. Using this method, a linear calibration curve for mesotrione
was obtained up to the 0.1 μM range in pH 7 phosphate buffer solution with a detection limit (S/N = 3) of 50 nM. The method
can be applied successfully to the determination of mesotrione in soils.
The text was submitted by the authors in English. 相似文献
7.
8.
Volkan Kseli Zakir M. O. Rzaev Erhan Pikin 《Journal of polymer science. Part A, Polymer chemistry》2003,41(11):1580-1593
Stimuli‐responsive poly[(N‐isopropylacrylamide‐co‐maleic anhydride)‐g‐poly(ethylene oxide)]/poly(ethylene imine) macrobranched macrocomplexes were synthesized by (1) the radical copolymerization of N‐isopropylacrylamide and maleic anhydride with α,α′‐azobisisobutyronitrile as an initiator in 1,4‐dioxane at 65 °C under a nitrogen atmosphere, (2) the polyesterification (grafting) of prepared poly(N‐isopropylacrylamide‐co‐maleic anhydride) containing less than 20 mol % anhydride units with α‐hydroxy‐ω‐methoxy‐poly(ethylene oxide)s having different number‐average molecular weights (Mn = 4000, 10,000, or 20,000), and (3) the incorporation of macrobranched copolymers with poly(ethylene imine) (Mn = 60,000). The composition and structure of the synthesized copolymer systems were determined by Fourier transform infrared, 1H and 13C NMR spectroscopy, and chemical and elemental analyses. The important properties of the copolymer systems (e.g., the viscosity, thermal and pH sensitivities, and lower critical solution temperature behavior) changed with increases in the molecular weight, composition, and length of the macrobranched hydrophobic domains. These copolymers with reactive anhydride and carboxylic groups were used for the stabilization of penicillin G acylase (PGA). The conjugation of the enzyme with the copolymers significantly increased the thermal stability of PGA (three times at 45 °C and two times at 65 °C). © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1580–1593, 2003 相似文献
9.
GM(1,1)改进模型及其应用 总被引:34,自引:1,他引:33
根据 GM( 1 ,1 )灰色模型的指数特性 ,通过在区间上求积分给出了关于背景值的一个比较确切的计算公式 ,讨论了由此建立的 GM( 1 ,1 )改进模型的适用范围和预测精度 .结果表明改进模型比原 GM( 1 ,1 )模型适用性要强、模拟和预测精度要高 ,不仅适用于低增长序列、也适用于高增长序列 ,不仅适用于短期预测 ,同样也适用于中、长期预测 相似文献
10.
In this paper, we explore a weakness of a specific implementation of the analytic center cutting plane method applied to convex optimization problems, which may lead to weaker results than Kelley's cutting plane method. Improvements to the analytic center cutting plane method are suggested, and tested on some example problems. 相似文献