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991.
992.
In this study, we reported electrochemical synthesis of conductive polypyrrole‐chitosan (PPY‐CHI) thin film for sensitive detection of sulfite in real samples. The synthesized PPY‐CHI film was characterized in terms of surface morphology, optical property, binding energy, conductivity and electrochemical properties. The synthesized copolymeric PPY‐CHI film displayed good electrocatalytic behaviour towards oxidation of sulfite. The synthesized PPY‐CHI film was used for sulfite detection using differential pulse voltammetric technique with detection limit, sensitivity and linearity of 0.21 μM (S/N=3), 15.28 μA μM cm?2 and 50–1100 μM respectively. In addition, the current responses of PPY‐CHI film towards sulfite were repeatable, reproducible response and unaffected by selected electroactive interferents. Finally, the synthesized PPY‐CHI was successfully and satisfactorily applied for determination of sulfite in real food and biological samples. The results obtained from this study highly placed PPY‐CHI film as a promising sensor for sensitive and accurate detection of sulfite in food and biological samples for human health protection. 相似文献
993.
Daghlavi Amneh Kowsari Elaheh Abdouss Majid Ghasemi Mohammad Hadi Asadi Elham 《Research on Chemical Intermediates》2020,46(7):3593-3605
Research on Chemical Intermediates - A practical and efficient method for the synthesis of thiazolidine derivatives via Nef-isocyanide three-component reaction using supported phosphoric acid on... 相似文献
994.
Zamani Azam Sadjadi Mirabdullah Seyed Mahjoub Alireza Yousefi Mohammad Farhadyar Nazanin 《Research on Chemical Intermediates》2020,46(1):33-61
Research on Chemical Intermediates - Magnetic ZnFe2O4@MnO–graphene oxide and ZnFe2O4@MnO–reduced graphene oxide nanocomposites were prepared via a facile co-precipitation and... 相似文献
995.
Shoja Sajede Mahmoodi Nosrat Ollah Ghafouri Hossein Rassa Mehdi Sharafshah Alireza Panahi Kokhdan Esmaeel 《Research on Chemical Intermediates》2020,46(7):3327-3339
Research on Chemical Intermediates - The structure of urea has received special attention due to its biological activity. A new and efficient one-pot three-component reaction for the synthesis of... 相似文献
996.
Gyeong Cheol Park Weiqi Xue Alireza Taghizadeh Elizaveta Semenova Kresten Yvind Jesper Mrk Il‐Sug Chung 《Laser \u0026amp; Photonics Reviews》2015,9(3):L11-L15
We experimentally demonstrate an optically‐pumped III‐V/Si vertical‐cavity laser with lateral emission into a silicon waveguide. This on‐chip hybrid laser comprises a distributed Bragg reflector, a III‐V active layer, and a high‐contrast grating reflector, which simultaneously funnels light into the waveguide integrated with the laser. This laser has the advantages of long‐wavelength vertical‐cavity surface‐emitting lasers, such as low threshold and high side‐mode suppression ratio, while allowing integration with silicon photonic circuits, and is fabricated using CMOS compatible processes. It has the potential for ultrahigh‐speed operation beyond 100 Gbit/s and features a novel mechanism for transverse mode control.
997.
Hadi Kargar Majid Moghadam Valiollah Mirkhani Shahram Tangestaninejad Iraj Mohammadpoor-Baltork Simindokht Rezaei 《Transition Metal Chemistry》2013,38(1):1-5
The oxidation of 2-substituted imidazolines with sodium periodate catalyzed by tetrakis(p-aminophenyl)-porphyrinatomanganese(III) chloride, [Mn(TNH2PP)Cl], supported on functionalized multi-wall carbon nanotubes is reported. A wide variety of 2-imidazolines were efficiently converted to their corresponding imidazoles by this catalytic system. When the same reaction was subjected to ultrasonic irradiation, the reaction times were reduced significantly and the product yields were increased. This catalyst could be reused several times without significant loss of activity. The effects of reaction parameters such catalyst amount, choice of solvent, and the effects of ultrasonic irradiation on the catalytic activity have been investigated. 相似文献
998.
基于纳米结构的电化学传感器用于伏安法测定苄丝肼、尿酸和叶酸(英文) 总被引:1,自引:0,他引:1
Sakineh Esfandiari Baghbamidi Hadi Beitollahi Seyed Zia Mohammadi Somayeh Tajik Somayeh Soltani-Nejad Vahhab Soltani-Nejad 《催化学报》2013,34(10):1869-1875
A carbon paste electrode modified with carbon nanotubes and ferrocene was fabricated.An electrochemical study of the modified electrode and an investigation into its efficiency for the electrocatalytic oxidation of benserazide,uric acid and folic acid were undertaken.The electrode was also used to study the electrocatalytic oxidation of benserazide using cyclic voltammetry,chronoamperometry,and square wave voltammetry(SWV).We found that the oxidation of benserazide at the surface of the modified electrode occurs at a potential about 285 mV lower than that of unmodified carbon paste electrode.SWV gave a linear dynamic range from 8.0×10-7 to 7.0×10 4 mol/L.The detection limit was 1.0×10-7 mol/L for benserazide.This modified electrode was used for the determination of benserazide,uric acid,and folic acid in an urine sample. 相似文献
999.
Hadi BEITOLLAHI Alireza MOHADESI Farzaneh GHORBANI Hassan KARIMI MALEH Mehdi BAGHAYERI Rahman HOSSEINZADEH 《催化学报》2013,34(7):1333-1338
A benzoylferrocene modified multi‐wall carbon nanotube paste electrode for the measurement of methionine (MET) concentration is described. MET electrochemical response characteristics of the modified electrode in a phosphate buffer solution of pH 7.0 were investigated by cyclic voltammetry, square wave voltammetry, and chronoamperometry. Under optimized conditions, the square wave voltammetric peak current of MET increased linearly with MET concentration in the range of 1.0×107 to 2.0×104 mol/L. The detection limit was 58.0 nmol/L MET. The diffusion coefficient (D=5.62×106cm2/s) and electron transfer coefficient (α=0.4) for MET oxidation were also determined. The sensor was successfully applied for the measurement of MET concentration in human urine. 相似文献
1000.
A carbon paste electrode (CPE) modified with carbon nanotubes and 5‐amino‐3’,4’‐dimethyl‐ bi‐ phenyl‐2‐ol (5ADB) is prepared. Under the optimum pH of 7.0, the oxidation of ascorbic acid (AA) on the modified CPE occurs at a potential about 280 mV less positive than that on the unmodified CPE. Some kinetic and thermodynamic parameters for electrocatalytic oxidation of AA, including electron transfer coefficient (α = 0.58) and diffusion coefficient (D = 2.2 × 10-6 cm2/s), are also determined. AA, acetaminophen (AC), and tryptophan (TRP) were detected simultaneously using the modified CPE. The peak potentials recorded using the modified CPE in phosphate‐buffered solution at pH 7.0 were 265, 465, and 780 mV for AA, AC, and TRP, respectively. The modified CPE was successfully used to determine the concentrations of AA, AC, and TRP in real samples. 相似文献