The coulometric titration of the derivatives of N,N-dimethyl-4-aminoazobenzene by generated trivalent titanium

1990 ◽  
Vol 55 (2) ◽  
pp. 391-402 ◽  
Author(s):  
Jiří Barek ◽  
Helena Kvapilová ◽  
Tibor Pastor ◽  
Jiří Zima
Keyword(s):  
Current Efficiency ◽  
Electrochemical Behaviour ◽  
Coulometric Titration ◽  
Acetic Acid Solution ◽  
Mercury Electrode ◽  
System A ◽  
Current Density Range ◽  
Derivatives Of ◽  
Trivalent Titanium ◽  
A Current

Conditions for the coulometric generation of titanium(III) ions in buffer medium in the presence of sodium citrate were found on the basis of a study of the electrochemical behaviour of the Ti(III)/Ti(IV) system. A current efficiency of 100% was attained in acetic acid solution (c = 1 mol l-1) containing citric acid (c = 0.2 mol l-1) and titanium (IV) chloride (c = 0.1 mol l-1), with pH adjusted to 6 using sodium hydroxide, in the current density range 0.5 to 10 mA/cm2 using a mercury electrode and 1 to 2 mA/ cm2 using a paraffin-impregnated spectrographic carbon electrode. It was found that methanol does not affect the current efficiency at contents of up to 33% (v/v) and conditions were found for the coulometric titration of small amounts (0.2-2 mg) of some genotoxic derivatives of N,N-dimethyl-4-aminoazobenzene.

The electrochemical behaviour of 2′-halogenated derivatives of 4-methoxyazobenzene at a mercury electrode

2010 ◽  
Vol 87 (1) ◽  
pp. 55-61 ◽  
Author(s):  
M. Uçar ◽  
K. Polat ◽  
A.O. Solak ◽  
M. Toy ◽  
M.L. Aksu
Keyword(s):  
Electrochemical Behaviour ◽  
Mercury Electrode ◽  
Derivatives Of

Methane synthesis from CO2 and H2O with electricity using H-permeable membrane electrochemical cells with Ru catalyst and phosphate electrolyte

2021 ◽  
Vol 5 (4) ◽  
pp. 935-940
Author(s):  
Jun Kubota ◽  
Takaya Okumura
Keyword(s):  
Current Efficiency ◽  
Electrochemical Cells ◽  
Permeable Membrane ◽  
Ru Catalyst ◽  
Electrochemical Conversion ◽  
A Current ◽  
Phosphate Electrolyte

Direct electrochemical conversion of CO2 and H2O to CH4 in a combined Ru-catalyst and H2O electrolyzer system was examined at 270 °C, thus obtaining a current efficiency of 93% for CH4 formation.

Dramatic efficiency improvement in single-layer orange phosphorescent organic light-emitting devices with suppressed efficiency roll-off

RSC Advances ◽  
2016 ◽  
Vol 6 (60) ◽  
pp. 55017-55021 ◽  
Author(s):  
Liangmei Zuo ◽  
Guangguang Han ◽  
Ren Sheng ◽  
Kaiwen Xue ◽  
Yu Duan ◽  
...  
Keyword(s):  
Current Efficiency ◽  
Single Layer ◽  
Efficiency Improvement ◽  
Light Emitting ◽  
Light Emitting Devices ◽  
Organic Light ◽  
Organic Light Emitting Devices ◽  
A Current

We have successfully demonstrated efficient single-layer organic light-emitting devices (OLEDs) with a current efficiency of 31.38 cd A−1.

scholarly journals Analytical Modeling and Validation of a Preloaded Piezoceramic Current Output

Micromachines ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 353
Author(s):  
Bin Zhang ◽  
Hongsheng Liu ◽  
Dezhi Li ◽  
Jinhui Liang ◽  
Jun Gao
Keyword(s):  
Energy Harvesting ◽  
Integrated Circuit ◽  
Microelectromechanical Systems ◽  
Experimental Testing ◽  
Current Source ◽  
Model Parameters ◽  
Current Output ◽  
System A ◽  
A Current ◽  
Piezoelectric Characteristics

Energy harvesting using piezoceramic has drawn a lot of attention in recent years. Its potential usage in microelectromechanical systems is starting to become a reality thanks to the development of an integrated circuit. An accurate equivalent circuit of piezoceramic is important in energy harvesting and the sensing system. A piezoceramic is always considered to be a current source according to empirical testing, instead of the derivation from its piezoelectric characteristics, which lacks accuracy under complicated mechanical excitation situations. In this study, a new current output model is developed to accurately estimate its value under various kinds of stimulation. Considering the frequency, amplitude and preload variation imposed on a piezoceramic, the multivariate model parameters are obtained in relation to piezo coefficients. Using this model, the current output could be easily calculated without experimental testing in order to quickly estimate the output power in energy harvesting whatever its geometric shape and the various excitations.

scholarly journals Mathematical modelling of the mass-spring-damper system - A fractional calculus approach

2012 ◽  
Vol 22 (5) ◽  
pp. 5-11 ◽  
Author(s):  
José Francisco Gómez Aguilar ◽  
Juan Rosales García ◽  
Jesus Bernal Alvarado ◽  
Manuel Guía
Keyword(s):  
Differential Equation ◽  
Fractional Calculus ◽  
Mathematical Modelling ◽  
Fractional Differential Equation ◽  
Fractional Order ◽  
Time Derivative ◽  
System A ◽  
Fractional Differential ◽  
Mass Spring ◽  
Derivatives Of

In this paper the fractional differential equation for the mass-spring-damper system in terms of the fractional time derivatives of the Caputo type is considered. In order to be consistent with the physical equation, a new parameter is introduced. This parameter char­acterizes the existence of fractional components in the system. A relation between the fractional order time derivative and the new parameter is found. Different particular cases are analyzed

Polarographic and voltammetric determination of genotoxic nitro derivatives of quinoline using mercury electrodes

2011 ◽  
Vol 76 (12) ◽  
pp. 1991-2004 ◽  
Author(s):  
Vlastimil Vyskočil ◽  
Ivan Jiránek ◽  
Aleš Daňhel ◽  
Jiří Zima ◽  
Jiří Barek ◽  
...  
Keyword(s):  
Differential Pulse Voltammetry ◽  
River Water ◽  
Mercury Electrode ◽  
Differential Pulse ◽  
Dropping Mercury Electrode ◽  
Separation And Preconcentration ◽  
Nitro Derivatives ◽  
Pulse Voltammetry ◽  
Derivatives Of

Electrochemical behavior of genotoxic nitro derivatives of quinoline, namely 5-nitroquinoline (5-NQ), 6-nitroquinoline (6-NQ) and 8-nitroquinoline (8-NQ), was investigated by DC tast polarography (DCTP) and differential pulse polarography (DPP), both at a classical dropping mercury electrode (DME), and by differential pulse voltammetry (DPV) and adsorptive stripping differential pulse voltammetry (AdSDPV), both at a miniaturized hanging mercury drop minielectrode (HMDmE), in buffered aqueous (for 5-NQ) or aqueous-methanolic (for 6-NQ and 8-NQ) solutions. Optimum conditions were found for the determination of 5-NQ, 6-NQ and 8-NQ by DCTP at DME (with limits of quantification, LQ ≈ 9 × 10–7, 3 × 10–7 and 2 × 10–6 mol l–1, respectively), by DPP at DME (LQ ≈ 1 × 10–8, 9 × 10–8 and 1 × 10–7 mol l–1, respectively), by DPV at HMDmE (LQ ≈ 2 × 10–8, 1 × 10–7 and 1 × 10–7 mol l–1, respectively), and by AdSDPV at HMDmE (LQ ≈ 1 × 10–8 mol l–1 for 8-NQ; an attempt at increasing the sensitivity using AdSDPV at HMDmE was not successful for 5-NQ and 6-NQ). Practical applicability of the developed methods was verified on the direct determination of the studied compounds in model samples of drinking and river water in submicromolar concentrations and on the determination in model samples of drinking and river water using preliminary separation and preconcentration by solid phase extraction (SPE) in nanomolar concentrations.

Etude polarographique de l'antimoine(III) et (V) dans le fluorure d'hydrogène anhydre et dans ses mélanges avec l'eau

1978 ◽  
Vol 56 (5) ◽  
pp. 703-708 ◽  
Author(s):  
Jacques Devynck ◽  
Bernard Tremillon ◽  
Hugues Menard ◽  
Germain Comarmond
Keyword(s):  
Electrochemical Reaction ◽  
Electrochemical Behaviour ◽  
Mercury Electrode ◽  
Analytical Applications ◽  
Dropping Mercury Electrode

The electrochemical behaviour of Sb(III) and Sb(V) in water–HF mixtures (2.5 to 50% HF) and in anhydrous HF is described. A Teflon capillary dropping mercury electrode is proposed for polarographie investigations in these fluorinated media. It is shown, by classical or puise polarography, that Sb(III) can be reduced to Sb(0), as in acidic non-fluorinated media. The electrochemical reaction becomes reversible by addition of Cl−, Br− or I−. Sb(V) is not electroactive in the various HF-media, except when it is introduced as the SbCl5. In this case, the two polarographie waves of Sb(V) disappear with time because of SbF6− formation. Analytical applications to the determination of Sb(III) in water–HF and in anhydrous HF are discussed.

Attributes for Executing Change in an Agile Information System

2015 ◽  
Vol 6 (2) ◽  
pp. 30-58 ◽  
Author(s):  
Pankaj Chaudhary ◽  
Micki Hyde ◽  
James A Rodger
Keyword(s):  
Information System ◽  
Factor Analysis ◽  
Information Systems ◽  
Real Time ◽  
Exploratory Factor Analysis ◽  
System A ◽  
Current Topic ◽  
Definition Of ◽  
A Current

Information Systems (IS) agility is a current topic of interest in the IS industry. The study follows up on work on the definition of the construct of IS agility and attributes for sensing and diagnosis in an agile IS. IS agility is defined as the ability of an IS to sense a change in real time; diagnose it in real time; and select and execute an action in real time. This paper explores the attributes for selecting and executing a response in an Agile Information System. A set of attributes were initially derived using the practitioner literature and then refined using interviews with practitioners. The attributes' importance and validity was established using a survey of the industry. All attributes derived in this study were deemed pertinent for selecting and executing a change in an agile information system. Dimensions underlying these attributes were identified using Exploratory Factor Analysis. This list of attributes can form the basis for assessing and establishing execution mechanisms to increase IS Agility.

Sign in / Sign up

Export Citation Format

Share Document