期刊文献+
共找到37篇文章
< 1 2 >
每页显示 20 50 100
Deposition of cerium contained conversion films on LC4 alloy with square wave pulse method 被引量:1
1
作者 ZHANGWei LIJiuqing +2 位作者 WUYinshun ZHANGPei HEJianping 《Rare Metals》 SCIE EI CAS CSCD 2004年第1期48-52,共5页
Cerium contained conversion films were deposited on LC4 aluminum alloy usingsquare wave pulse (SWP) in a CeCl_3 solution with KMnO_4 as the oxidant. Energy dispersivespectroscopy (EDS) and scanning electron microscopy... Cerium contained conversion films were deposited on LC4 aluminum alloy usingsquare wave pulse (SWP) in a CeCl_3 solution with KMnO_4 as the oxidant. Energy dispersivespectroscopy (EDS) and scanning electron microscopy (SEM) were adopted to study the composition andthe morphology of the film. It is found that the film is composed of Al, Zn, Cu, and small amount ofcerium. The polarization curves of the specimens treated with SWP technique measured in 3.5% (massfraction) NaCl solution reveal that the film thus formed inhibits both the anodic and cathodicprocess of the corrosion of the specimen. The immersion tests of treated specimens in 3.5% NaClsolution indicate that the corrosion resistance of the SWP treated specimen is better than that ofthe untreated and is equivalent to or even better than that of the traditionally electro-chemicallytreated specimens. 展开更多
关键词 aluminum alloy conversion film square wave pulse rare earth metal
下载PDF
A Compact System of Capacitively Coupled Contactless Conductivity Detection Based on the Square Wave Excitation Signal for Capillary Electrophoresis 被引量:1
2
作者 Shui Feng ZHANG Li Shi WANG Zhi DANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第9期1229-1232,共4页
This paper reported a compact system of capacitively coupled contactless conductivity detection (C4D) based on the square wave excitation voltage for capillary electrophoresis, and it exhibited excellent sensitivity... This paper reported a compact system of capacitively coupled contactless conductivity detection (C4D) based on the square wave excitation voltage for capillary electrophoresis, and it exhibited excellent sensitivity at the optimal frequency of 198 kHz. The feasibility and sensitivity of this detector was demonstrated by simultaneous detection of thirteen ions including alkali, alkaline earth and heavy metal ions. And the detection limits (S/N 3) were in the range of 0.2-1μmol/L for Mn^2+, K^+, Na^+, Mg^2+, Ca^2+, Li^+, Ba^2+, and 7-25 μmol/L for Ni^2+, Cu^2+, Cd^2+, Pb^2+, Co^2+, Zn^2+. 展开更多
关键词 Capillary electrophoresis square wave excitation signal contactless conductivitydetector metal ions.
下载PDF
Research on Fault-tolerant Operation Strategy of Rectifier of Square Wave Motor in Wind Power System 被引量:3
3
作者 Chunyuan Bian Shangyue Liu +1 位作者 Haiyang Xing Yulong Jia 《CES Transactions on Electrical Machines and Systems》 CSCD 2021年第1期62-69,共8页
In wind power system,the randomness of wind energy increases the probability of components fault.once the switch fault of the PWM rectifier is detected,it will lead to the distortion of the motor voltage and current w... In wind power system,the randomness of wind energy increases the probability of components fault.once the switch fault of the PWM rectifier is detected,it will lead to the distortion of the motor voltage and current waveform,the increase of torque ripple,the fluctuation of filter capacitor voltage,and the increase of harmonic content,which will affect the control performance and operation safety of the system.A common fault in a three-phase PWM rectifier is the open-circuit fault of the switch.This paper analyzes the current waveform distortion of the square wave motor when the rectifier switch fault,and proposes different fault-tolerant control strategies for different situations of switch fault,include single,double and triple switches fault.This method is based on several special driving modes under power generation situation of square wave motor.The strategy is easy to implement and does not need to change the circuit topology.It can realize fault-tolerant control of switch faults in the same side half bridge or the same bridge arm of the three-phase PWM rectifier.The effectiveness of the proposed fault-tolerant strategy is verified by simulation and experiment at the end of the article. 展开更多
关键词 square wave motor fault-tolerant operation PWM rectifier.
下载PDF
Osteryoung square wave voltammetric determination of lactose in food samples by a derivative procedure
4
作者 Yong Nian Ni Yue Rong Wang Serge Kokot 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第12期1491-1494,共4页
A method for determination of lactose in food samples by Osteryoung square wave voltammetry (OSWV) was developed. It was based on the nucleophilic addition reaction between lactose and aqua ammonia. The carbonyl gro... A method for determination of lactose in food samples by Osteryoung square wave voltammetry (OSWV) was developed. It was based on the nucleophilic addition reaction between lactose and aqua ammonia. The carbonyl group of lactose can be changed into imido group, and this increases the electrochemical activity in reduction and the sensitivity. The optimal condition for the nucleophilic addition reaction was investigated and it was found that in NH4C1-NH3 buffer of pH 10.1, the linear range between the peak current and the concentration of lactose was 0.6-8.4 mg L-l, and the detection limits was 0.44 mg L- 1. The proposed method was applied to the 'determination of lactose in food samples and satisfactory results were obtained. 展开更多
关键词 Osteryoung square wave voltammetry LACTOSE FOOD MILK
下载PDF
A Square Wave Based Electrical Method for Human Skin Moisture Assessment
5
作者 Guolin Zhou Yonggui Dong 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期463-466,共4页
The moisture content measurement of human skin is a significant way to assess skin conditions and diagnose diseases that influence skin function.The necessity of evaluating the efficacy of a cosmetic product makes it ... The moisture content measurement of human skin is a significant way to assess skin conditions and diagnose diseases that influence skin function.The necessity of evaluating the efficacy of a cosmetic product makes it important to improve the accuracy and reproducibility of the measurement.A pair of interdigitated gold electrodes was fabricated on the printed circuit board (PCB) substrate and utilized directly in contact with the measured skin.A square-wave voltage at a single frequency was applied to the electrodes and the corresponding response current was measured to get the equivalent impedance of human skin.Since it's easy to generate and control a square-wave signal by digital electric circuits,this method is suitable to be used in the portable application.The experimental results indicate that good repeatability and satisfied accuracy can be obtained by this method. 展开更多
关键词 skin moisture content square wave skin impedance single frequency
下载PDF
Determination of ziram in vegetable samples by square wave voltammetry
6
作者 Ping Qiu Yong Nian Ni 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第11期1337-1340,共4页
The electrochemical behaviour and electrode reaction mechanism of ziram (zinc-dimethyl dithiocarbamate) on a hanging mercury drop electrode were investigated in Britton-Robinson (B-R) buffer by using cyclic and sq... The electrochemical behaviour and electrode reaction mechanism of ziram (zinc-dimethyl dithiocarbamate) on a hanging mercury drop electrode were investigated in Britton-Robinson (B-R) buffer by using cyclic and square wave voltammetry (SWV). Based on these studies a voltammetric method for determination of ziram wasdeveloped and applied to determine the ziram in synthetic and spiked vegetable samples, satisfactory results were obtained in both cases. 展开更多
关键词 ZIRAM square wave voltammetry PESTICIDE
下载PDF
CuO-nanoparticles modified carbon paste electrode for square wave voltammetric determination of lidocaine: Comparing classical and Box–Behnken optimization methodologies 被引量:3
7
作者 Nadereh Rahbar Zahra Ramezani Jamalaldin Ghanavati 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第6期837-842,共6页
In this research, copper oxide nanoparticles modified carbon paste electrode was developed for the voltammetric determination of lidocaine. The square wave voltammogram of lidocaine solution showed a well-defined peak... In this research, copper oxide nanoparticles modified carbon paste electrode was developed for the voltammetric determination of lidocaine. The square wave voltammogram of lidocaine solution showed a well-defined peak between +0.5 and +1.5 V. Instrumental and chemical parameters influencing voltammetric response were optimized by both one at a time and Box–Behnken model of response surface methodology. The results revealed that there was no significant difference between two methods of optimization. The linear range was 1–2500 μmol L^-1(Ip= 0.11 C(LH)+ 17.38, R^2= 0.999). The LOD and LOQ based on three and ten times of the signal to noise(S/N) were 0.39 and 1.3 μmol L^-1(n = 10),respectively. The precision of the method was assessed for 10 replicate square wave voltammetry(SWV)determinations each of 0.05, 0.5 and 1 μmol L^-1 of lidocaine showing relative standard deviations 4.1%,3.7% and 2.1%, respectively. The reliability of the proposed method was established by application of the method for the determination of lidocaine in two pharmaceutical preparations, namely injection and gel. 展开更多
关键词 square wave voltammetry CuO nanoparticles LIDOCAINE Modified carbon paste electrode
原文传递
EFFECTIVE DOUBLE LOOP CONTROL FOR A SQUARE WAVE BRUSHLESS DC MOTOR
8
作者 周波 李先祥 朱震莲 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1996年第2期34+30-33,共5页
A new type of brushless DC motor has been developed by using a square wave rare earth permanent magnet synchronous motor with its double loop control circuit. The double loop control scheme of the drive system yie... A new type of brushless DC motor has been developed by using a square wave rare earth permanent magnet synchronous motor with its double loop control circuit. The double loop control scheme of the drive system yields a combination of desired characteristics including simplified control structure, small ripple torque, high speed accuracy, wide operating speed range, and fast dynamic response. Experimental results confirm excellent characteristics of the motor. 展开更多
关键词 synchronous motors speed control systems INVERTERS brushless DC motor double loop control square wave motors
下载PDF
Ac voltammetric and square wave voltammetric study of the self-assembled monolayers of thiol-functionalized viologen derivative
9
作者 Li, JH Yang, CH +2 位作者 Yan, JC Chen, WQ Dong, SJ 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1997年第2期130-137,共8页
Electroactive self-assembled monolayers (SAMs) containing viologen group are formed through the adsorption of thiol-functionalized viologen compound CH3(CH2)(9)V2+(CH2)(8)SH, where V2+ is N,N'-dialkylbipyridinium ... Electroactive self-assembled monolayers (SAMs) containing viologen group are formed through the adsorption of thiol-functionalized viologen compound CH3(CH2)(9)V2+(CH2)(8)SH, where V2+ is N,N'-dialkylbipyridinium (i.e. a viologen group), onto gold electrodes from methanol/water solution and its electrochemical behavior is investigated ty Ac voltammetry and square wave voltammetry, which have the high sensitivity against background charging. The viologen SAM formed is a sub-monolayer and the normal potentials corresponding to the two successive one-electron transfer processes of the active centers (viologen) are -360 mV and -750 mV (vs. Ag/AgCl) in 0.1 mol/L phosphate buffer solutions (pH 6.96) respectively, and the standard electron transfer rate constant is 9.0 s(-1). The electrochemical behavior of this SAM in various solutions has been preliminarily discussed. 展开更多
关键词 self-assembled monolayers VIOLOGEN Ac voltammetry square wave voltammetry
原文传递
Indirect Electroanalysis of 3-Methyl-4-Nitrophenol in Water Using Carbon Fiber Microelectrode Modified with Nickel Tetrasulfonated Phthalocyanine Complex
10
作者 Yibor Fabrice Roland Bako Serge Foukmeniok Mbokou +2 位作者 Boukaré Kaboré Issa Tapsoba Maxime Pontié 《Materials Sciences and Applications》 2024年第2期25-35,共11页
Electrochemical detection of 3-methyl-4-nitrophenol (MNP) in direct phenol oxidation occurs at high potentials and generally leads to progressive passivation of the electrochemical sensor. This study describes the use... Electrochemical detection of 3-methyl-4-nitrophenol (MNP) in direct phenol oxidation occurs at high potentials and generally leads to progressive passivation of the electrochemical sensor. This study describes the use of a carbon fiber microelectrode modified with a tetrasulfonated nickel phthalocyanine complex for the detection of MNP at a lower potential than that of direct phenol oxidation. The MNP voltammogram showed the presence of an anodic peak at -0.11 V vs SCE, corresponding to the oxidation of the hydroxylamine group generated after the reduction of the nitro group. The effect of buffer pH on the peak current and SWV parameters such as frequency, scan increment, and pulse amplitude were studied and optimized to have better electrochemical response of the proposed sensor. With these optimal parameters, the calibration curve shows that the peak current varied linearly as a function of MNP concentration, leading to a limit of detection (LoD) of 1.1 μg/L. These results show an appreciable sensitivity of the sensor for detecting the MNP at relatively low potentials, making it possible to avoid passivation phenomena. 展开更多
关键词 3-Methyl-4-Nitrophenol Carbon Fiber Microelectrode Nickel Tetrasulfonated Phthalocyanine Indirect Electroanalysis square wave Voltammetry
下载PDF
Calibration of HY-2A satellite significant wave heights with in situ observation 被引量:2
11
作者 PENG Hailong LIN Mingsen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第3期79-83,共5页
Significant wave height(SWH) can be computed from the returning waveform of radar altimeter, this parameter is only raw estimates if it does not calibrate. But accurate calibration is important for all applications,... Significant wave height(SWH) can be computed from the returning waveform of radar altimeter, this parameter is only raw estimates if it does not calibrate. But accurate calibration is important for all applications, especially for climate studies. HY-2a altimeter has been operational since April 2012 and its products are available to the scientific community. In this work, SWH data from HY-2A altimeters are calibrated against in situ buoy data from the National Data Buoy Center(NDBC), Distinguished from previous calibration studies which generally regarded buoy data as "truth", the work of calibration for HY-2A altimeter wave data against in situ buoys was applied a more sophisticated statistical technique-the total least squares(TLS) method which can take into account errors in both variables. We present calibration results for HY-2A radar altimeter measurement of wave height against NDBC buoys. In addition, cross-calibration for HY-2A and Jason-2 wave data are talked over and the result is given. 展开更多
关键词 total least squares NDBC buoys HY-2A altimeter significant wave height
下载PDF
An AuNPs/Mesoporous NiO/Nickel Foam Nanocomposite as a Miniaturized Electrode for Heavy Metal Detection in Groundwater 被引量:1
12
作者 Boyuan Xue Qian Yang +4 位作者 Kaidong Xia Zhihong Li George Y.Chen Dayi Zhang Xiaohong Zhou 《Engineering》 SCIE EI CAS CSCD 2023年第8期199-208,共10页
Heavy metals,notably Pb2+and Cu^(2+),are some of the most persistent contaminants found in groundwater.Frequent monitoring of these metals,which relies on efficient,sensitive,cost-effective,and reliable methods,is a n... Heavy metals,notably Pb2+and Cu^(2+),are some of the most persistent contaminants found in groundwater.Frequent monitoring of these metals,which relies on efficient,sensitive,cost-effective,and reliable methods,is a necessity.We present a nanocomposite-based miniaturized electrode for the concurrent measurement of Pb2+and Cu^(2+)by exploiting the electroanalytical technique of square wave voltammetry.We also propose a facile in situ hydrothermal calcination method to directly grow binder-free mesoporous Ni O on a three-dimensional nickel foam,which is then electrochemically seeded with gold nanoparticles(Au NPs).The meticulous design of a low-barrier Ohmic contact between mesoporous Ni O and Au NPs facilitates target-mediated nanochannel-confined electron transfer within mesoporous Ni O.As a result,the heavy metals Pb2+(0.020 mg.L^(-1)detection limit;2.0–16.0 mg.L^(-1)detection range)and Cu^(2+)(0.013 mg.L^(-1)detection limit;0.4–12.8 mg.L^(-1)detection range)can be detected simultaneously with high precision.Furthermore,other heavy metal ions and common interfering ions found in groundwater showed negligible impacts on the electrode’s performance,and the recovery rate of groundwater samples varied between 96.3%±2.1%and 109.4%±0.6%.The compactness,flexible shape,low power consumption,and ability to remotely operate our electrode pave the way for onsite detection of heavy metals in groundwater,thereby demonstrating the potential to revolutionize the field of environmental monitoring. 展开更多
关键词 AuNPs Mesoporous NiO Miniaturized electrode Heavy metal ions GROUNDWATER square wave voltammetry
下载PDF
Preparation of dendritic bismuth film electrodes and their application for detection of trace Pb(Ⅱ)and Cd(Ⅱ) 被引量:3
13
作者 Huizhu Zhou Huanhuan Hou +3 位作者 Lei Dai Yuehua Li jing Zhu Ling Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第3期410-414,共5页
In this paper,dendritic Bi film electrodes with porous structure had successfully been prepared on glassy carbon electrode using a constant current electrolysis method based on hydrogen bubble dynamic templates.The el... In this paper,dendritic Bi film electrodes with porous structure had successfully been prepared on glassy carbon electrode using a constant current electrolysis method based on hydrogen bubble dynamic templates.The electrode prepared using a large applied current density showed an increased internal electroactive area and a significantly improved electrochemical performance.The analytical utility of the prepared dendritic Bi film electrodes for the determination of Pb(Ⅱ)and Cd(Ⅱ)in the range of 5–50 μg·L^(-1)were presented in combination with square wave stripping voltammetry in model solution.Compared with non-porous Bi film electrode,the dendritic Bi film electrode exhibited higher sensitivity and lower detection limit.The prepared Bi film electrode with dendritic structure was also successfully applied to real water sample analysis. 展开更多
关键词 Dendritic Bi film electrode ELECTRO-DEPOSITION Hydrogen bubble dynamic template square wave stripping analysis Pb(Ⅱ) and Cd(Ⅱ)
下载PDF
Reduction behavior of cerium(Ⅲ) ions in NaCl-2CsCl melt 被引量:2
14
作者 QIXue ZHUHongmin 《Rare Metals》 SCIE EI CAS CSCD 2005年第1期8-14,共7页
The cathodic process of cerium(III) ions in NaCl-2CsCl melt was studied bycyclic voltammetry and square wave voltammetry with tungsten and gold electrodes at 873 K. The twoelectroanalytical methods yield similar resul... The cathodic process of cerium(III) ions in NaCl-2CsCl melt was studied bycyclic voltammetry and square wave voltammetry with tungsten and gold electrodes at 873 K. The twoelectroanalytical methods yield similar results. The cathodic process of cerium(III) ions consistsof two reversible steps: Ce^(3+)+ e^-= Ce^(2+) and Ce^(2+) + 2e^-= Ce. The half wave potentials ofCe^(3+)/Ce^(2+) and Ce^(2+)/Ce were determined as -2.525 V vs. Cl_2/Cl^- and -2.975 V vs. Cl_2/Cl^-,respectively. The diffusion coefficient of Ce^(3+) was also determined as 5.5 X 10^(-5) cm^2 centredot s^(-1). 展开更多
关键词 CERIUM cathodic process molten salts square wave voltammetry CYCLICVOLTAMMETRY
下载PDF
Electrochemical Assay of Effects of Organophosphate Poisoning on Acetylcholinesterase from Pheretima via 2,6-Dimethyl-p-benzoquinone 被引量:1
15
作者 WU Wu-ai LI Jun +1 位作者 GAO Bao-ping GUO Man-dong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第4期600-603,共4页
Electroanalytical techniques could be a reliable and promising alternative to classical and sophisticated methods because of their simplicity(small and portable),easy use,the ability to deliver fast response with hi... Electroanalytical techniques could be a reliable and promising alternative to classical and sophisticated methods because of their simplicity(small and portable),easy use,the ability to deliver fast response with high sensitivity and selectivity.A square wave voltammetric method was developed for the assessment of organophosphorus(OPs) compound impact on acetylcholinesterase(AChE) of Pheretima with 2,6-dimethyl-p-benzoquinone(2,6DMBQ) as a redox indicator.The substrate of acetylthiocholine is hydrolyzed by AChE and the produced thiocholine reacts with 2,6-DMBQ to give an obvious shift of electrochemical signal.The reduction peak of 2,6-DMBQ is located at around 0.18 V which is far away from the oxidation potential of possible interference components often present in biosample.The decreased rate of reduction current was related with the activity of AChE.The inhibition of parathion-methyl on AChE was assessed.The inhibiton rate of OPs on AChE activity increased quickly during the first 10 min inhibition,and after that the value of inhibition rate approached to be constant.AChE lost almost 29.3% of activity after 10 min incubation with 1 μg/mL parathion-methyl and 67.5% of activity with 10 μg/mL parathion-methyl,while the activity that corresponds to 40 μg/mL parathion-methyl was nearly completely inhibited(94.9%).Compared to cyclic voltammetry and amperometry,Square wave voltammetry(SWV) method is a high sensitive electroanalysis with fast scan-rate(only several seconds for one signal value) which is useful to prevent the electrodes from possible fouling or passivation.This method can be employed to assess the inhibition of organophosphate on AChE and investigate OPs impact on environmental animals. 展开更多
关键词 2 6-Dimethyl-p-benzoquinone PHERETIMA Organophosphorous compound square wave voltammetry ACETYLCHOLINESTERASE
下载PDF
Mechanistic insights into homogeneous electrocatalytic reaction for energy storage using finite element simulation
16
作者 Peng Song Yan Li Shuang Yin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第2期285-296,共12页
The application of homogeneous electrocatalytic reactions in energy storage and conversion has driven surging interests of researchers in exploring the reaction mechanisms of molecular catalysts.In this paper,homogene... The application of homogeneous electrocatalytic reactions in energy storage and conversion has driven surging interests of researchers in exploring the reaction mechanisms of molecular catalysts.In this paper,homogeneous electrocatalytic reaction between hydroxymethylferrocene(HMF)and L-cysteine is intensively investigated by cyclic voltammetry and square wave voltammetry for which,the secondorder rate constant(k_(ec))of the chemical reaction between HMF^(+)and L-cysteine is determined via a 1D homogeneous electrocatalytic reaction model based on finite element simulation.The corresponding k_(ec)(1.1(mol·m^(-3))^(-1)·s^(-1))is further verified by linear sweep voltammograms under the same model.Square wave voltammetry parameters including potential frequency(f),increment(Estep)and amplitude(ESW)have been comprehensively investigated in terms of the voltammetric waveform transition of homogeneous electrocatalytic reaction.Specifically,the effect of potential frequency and increment is in accordance with the potential scan rate in cyclic voltammetry and the increase of pulsed potential amplitude results in a conspicuous split oxidative peaks phenomenon.Moreover,the proposed methodology of k_(ec)prediction is examined by hydroxyethylferrocene(HEF)and L-cysteine.The present work facilitates the understanding of homogeneous electrocatalytic reaction for energy storage purpose,especially in terms of electrochemical kinetics extraction and flow battery design. 展开更多
关键词 Homogeneous electrocatalytic reaction Electrochemical kinetics square wave voltammetry Finite element modelling Energy storage
下载PDF
Synthesis of carbon nanosheet from barley and its use as non-enzymatic glucose biosensor
17
作者 Soma Das Mitali Saha 《Journal of Pharmaceutical Analysis》 SCIE CAS 2014年第6期351-359,共9页
In this work,carbon nanosheet(CNS) based electrode was designed for electrochemical biosensing of glucose.CNS has been obtained by the pyrolysis of barley at 600-750℃ in a muffle furnace:it was then purified and f... In this work,carbon nanosheet(CNS) based electrode was designed for electrochemical biosensing of glucose.CNS has been obtained by the pyrolysis of barley at 600-750℃ in a muffle furnace:it was then purified and functionalized.The CNS has been characterized by scanning electron microscopy(SEM).X-ray diffraction(XRD) and Raman spectroscopic techniques.The electrochemical activity of CNS-based electrode was investigated by linear sweep vollammetry(LSV) and square wave voltammetry(SWV),for the oxidation of glucose in 0.001 M H2SO4(pH 6.0).The linear range of the sensor was found to be 10-4-10-6M(1-100 μM) within the response time of 4 s.Interestingly,its sensitivity reached as high as 26.002±0.01 μA/μM cm2.Electrochemical experiments revealed that the proposed electrode offered an excellent electrochemical activity towards the oxidation of glucose and could be applied for the construction of non-enzymatic glucose biosensors. 展开更多
关键词 Carbon nanosheet β-D glucose Linear sweep voltammetry square wave voltammetry Pharmaceutical analysis
下载PDF
Paracetamol Sensitive Cellulose-Based Electrochemical Sensors
18
作者 Maxime Pontie Serge Foukmeniok Mbokou +5 位作者 Jean-Philippe Bouchara Bienvenue Razafimandimby Sylvie Egloff Ornella Dzilingomo Pierre-Yves Pontalier Ignas Kenfack Tonle 《Journal of Renewable Materials》 SCIE 2018年第3期242-250,共9页
Electrochemical determination of paracetamol(PCT)was successfully performed using carbon paste electrodes(CPEs)modified with treated coffee husks(CHt)or cellulose powder(Ce).Scanning electron microscopy was used to ch... Electrochemical determination of paracetamol(PCT)was successfully performed using carbon paste electrodes(CPEs)modified with treated coffee husks(CHt)or cellulose powder(Ce).Scanning electron microscopy was used to characterize unmodified or modified CPEs prior to their use.The electrochemical oxidation of PCT was investigated using square wave voltammetry(SWV)and cyclic voltammetry(CV).The oxidation current density of PCT was two-fold higher with the CPE-CHt sensor and 30%higher with CPE-Ce in comparison with the unmodified CPE,and this correlated with the higher hydrophilicity of the modified electrodes.Using SWV for the electrochemical analysis of PCT,carbon paste electrode modified with raw coffee husks(CPE-CHr)showed the presence of impurities at+0.27 V/SCE,showing the interest in using pure cellulose for the present analytical application.Furthermore,CPE-Ce presented a higher real area compared to CPE-CHr,which explains the increase in the limit of saturation from 400 mg/L to 950 mg/L.The better saturation limit exhibited by CPE-Ce justifies its choice for electroanalysis of PCT in commercialized tablets.The proposed method was successfully applied in the determination of PCT in commercialized tablets(DolipraneR 500)with a recovery rate close to 100%,and no interference with the excipients contained in the tablets analyzed was observed.This novel sensor opens the way for sustainable development of electroanalytical control of drugs sold individually in developing countries. 展开更多
关键词 PARACETAMOL carbon paste electrode coffee husks cellulose fibers square wave voltammetry ELECTROANALYSIS
下载PDF
Investigations of Thallium(Ⅰ) Underpotential Deposition on the Silver Rotating Disk Electrode and Its Analytical Application
19
作者 WANG Chun ming ZHU Li 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2001年第1期102-107,共6页
The cyclic voltammetry(CV) and the square wave technique were used for the investigations of thallium(Ⅰ) underpotential deposition(UPD) on the silver electrode. A solution of 10 \{mmol/L\} HClO 4+10 mmol/L NaCl was s... The cyclic voltammetry(CV) and the square wave technique were used for the investigations of thallium(Ⅰ) underpotential deposition(UPD) on the silver electrode. A solution of 10 \{mmol/L\} HClO 4+10 mmol/L NaCl was selected as the supporting electrolyte. The calibration plots for Tl(Ⅰ) concentration in the range of 2×10 -9 -1×10 -7 mol/L were obtained. The detection limit was 5×10 -10 mol/L. For the solutions of 4 0×10 -9 mol/L thallium added before the urine sample pretreatment procedure, the average recovery was 105 6% with a relative standard deviation(RSD) of 15 5%. 展开更多
关键词 Thallium(Ⅰ) Underpotential deposition Silver rotating disk electrode Cyclic voltammetry square wave anodic stripping voltammetry
下载PDF
New Easy Method for the Monitoring of Hg Concentration in Fish, Using a Nanostructured Gold Electrode
20
作者 Agnese Giacomino Gabriella Schirinzi +3 位作者 Arianna Pandi Mery Malandrino Rosanna Toniolo Ornella Abollino 《Journal of Environmental Science and Engineering(A)》 2015年第7期378-387,共10页
The applicability of a gold nanoparticle-modified glassy carbon sensor (AuNPs-GCS) for the determination of inorganic mercury in fresh and canned tuna fish by square wave anodic stripping voltammetry (SW-ASV) is d... The applicability of a gold nanoparticle-modified glassy carbon sensor (AuNPs-GCS) for the determination of inorganic mercury in fresh and canned tuna fish by square wave anodic stripping voltammetry (SW-ASV) is demonstrated. Mercury content in sample Tuna Fish ISPRA T22 was determined to value the accuracy of the determination. The concentration in this sample is not certified, so, the Hg amount was determined also with atomic absorption spectroscopy (AAS): the results obtained with ASV were in good agreement and confirmed literature value reported for this sample. Then, real samples of tuna fish were analyzed. The voltammetric analyses were performed using previously optimized conditions (deposition potential 0 V, step potential 0.004 V, frequency 150 Hz and amplitude 0.003 V). Medium exchange technique permitted to eliminate possible matrix effects. The concentrations in the real samples were found to be in agreement with the common Hg levels reported in literature for commercialized tuna fish in different countries. 展开更多
关键词 Gold nanopartiele modified glassy carbon sensor square wave stripping voltammetry MERCURY tuna fish mediumexchange.
下载PDF
上一页 1 2 下一页 到第
使用帮助 返回顶部