this study demonstrates the use of a selective and sensitive voltammetric sensor for determination of acetaminophen (ac). this was  performed by modifying a glassy carbon electrode with composite film of poly(4-vinylpyridine) and graphene sheet (p4vp/gr-gce). the redox peak currents of ac increased significantly at p4vp/gr-gce. the result was achieved by the synergistic effect of combined elect...

development of yeast artificial chromosome (y ac) vectors, molecular cloning of large segments of chromosomal dna, and their propagation in yeast cells has become feasible. overlapping y ac provides a route to the development of physical maps of entire mammalian chromosomes. a rapid method was developed to isolate and sequence termini of y ac inserts quickly. the y ac clone is digested with a r...

This article proposes the study, control and analysis of topology an AC–AC modular multilevel converter, known in literature as Hexverter. The Hexverter is capable converting energy between two AC systems with a reduced number elements, if compared other topologies, which makes this attractive applications. However, there are few studies about literature, so work presents its operation principl...

Abstract. This work presents the design of robust sliding mode controllers for three-phase ac-ac matrix converters, in order to guarantee output sinusoidal waveforms and near unity input power factor. First, the sliding mode controller, based on the state-space vectors modulation technique, is designed for the matrix converter and the obtained results are compared to those obtained using the cl...

A high-speed capacitance difference-to-sum ratio measurement circuit is presented for differential capacitance transducers. It consists of a switched-capacitor input stage, two sample-and-hold (S/H) circuits followed by voltage-to-current (V/I) converters, and a current-ratio-controlled relaxation oscillator. This circuit offers a square-wave output whose oscillation period is directly proporti...