Vu D.L., Ertek B., Dilgin Y., Červenka L. (2015): Voltammetric determination of tannic acid in beverages using pencil graphite electrode. Czech J. Food Sci., 33: 72–76. The pretreated pencil graphite electrode (Pre-PGE) prepared by a chronoamperometry technique was applied for the determination of tannic acid using anodic stripping differential pulse voltammetry. The currents obtained from volt...

Unproctored, web-based assessments supposedly reduce social desirability distortions in self-report questionnaires because of an increased sense of privacy among participants. Three random-effects meta-analyses focusing either on social desirability ( k = 30, total N = 3,746), the Big Five of personality ( k = 66, total N = 2,951), or psychopathology ( k = 96, total N = 16,034) compared social ...

We consider the problem of approximating the generalized Schur decomposition of a matrix pencil A XB by a family of differentiable orthogonal transformations. It is shown that when B is nonsingular this approach is feasible and can be fully expressed as an autonomous differential system. When B is singular, we show that the location of zero diagonal entries of B affects the feasibility of such ...

Abstract. Differential-algebraic equations with a higher index can be approximated by regularization algorithms. One of such possibilities was introduced by März for linear time varying index 2 systems. In the present paper her approach is generalized to linear time varying index 3 systems. The structure of the regularized solutions and their convergence properties are characterized in terms of...

In this study, pencil graphite electrode was modified using conductive polypyrrole (Ppy) and grapheme (GF) nanocomposite for electrochemical determination of insulin. Electrochemical behavior of insulin on PGE was investigated using cyclic voltammetric (CV) and differential pulse voltammetric (DPV) and chronoaprometry (CA) methods. Several effective parameters including pH, concentration, and s...

We prove uniqueness theorems for so-called half inverse spectral problem (and also for some its modification) for second order differential pencils on a finite interval with Robin boundary conditions. Using the obtained result we show that for unique determination of the pencil it is sufficient to specify the nodal points only on a part of the interval slightly exceeding its half. Mathematics S...

the goal of this study was to investigate the effect of using computer conceptual maps­, compared with  usual way of drawing them by pencil and paper­, in increasing learning, recalling and educational progress motivation in geology course among high school students. the study was conducted in semi experimental method in which students of 3 classes were classified in 3 groups. (group 1: common ...