Interfacial Deposition of Titanium Dioxide at the Polarized Liquid–Liquid Interface

The interfacial polycondensation of titanium dioxide was studied at the bare and fiberglass membrane supported polarized liquid–liquid interface (LLI). Titanium dioxide synthesis was derived from the titanium (IV) tetrabutoxide (initially dissolved in the 1,2-dichloroethane) interfacial hydrolysis followed by its condensation. Experimental parameters, such as the pH of the aqueous phase and the influence of titanium alkoxide concentration in the organic phase on the electrochemical signal and material morphology, were investigated. The latter was achieved with fiberglass membranes used as the LLI support during TiO2 interfacial deposition. Cyclic voltammetry was used for the in situ studies, whereas scanning electron microscopy, energy-dispersive X-ray spectroscopy, and infrared spectroscopy were used during ex situ examination. The interfacial polycondensation reaction could be studied using electrified LLI and resulted in the material being a TiO2 film alone or film decorated with particles

Solvent-activated 3D-printed electrodes and their electroanalytical potential

Abstract This work is a comprehensive study describing the optimization of the solvent-activated carbon-based 3D printed electrodes. Three different conductive filaments were used for the preparation of 3D-printed electrodes. Electrodes treatment with organic solvents, electrochemical characterization, and finally electroanalytical application was performed in a dedicated polyamide-based cell also created using 3D printing. We have investigated the effect of the used solvent (acetone, dichloromethane, dichloroethane, acetonitrile, and tetrahydrofuran), time of activation (from immersion up to 3600 s), and the type of commercially available filament (three different options were studied, each being a formulation of a polylactic acid and conductive carbon material). We have obtained and analysed a significant amount of collected data which cover the solvent-activated carbon-based electrodes surface wettability, microscopic insights into the surface topography analysed with scanning electron microscopy and atomic force microscopy, and finally voltammetric evaluation of the obtained carbon electrodes electrochemical response. All data are tabulated, discussed, and compared to finally provide the superior activation procedure. The electroanalytical performance of the chosen electrode is discussed based on the voltammetric detection of ferrocenemethanol

The TDCPix ASIC: Tracking for the NA62 GigaTracker

The TDCPix is a hybrid pixel detector readout ASIC designed for the NA62 GigaTracker detec- tor. The asynchronously operating pixel array consists of 1800 pixels, each 300x300 m m 2 . The requirements are a single-hit timing resolution better than 200 ps RMS and a read-out efficiency of 99% or better in the presence of a beam rate between 800 MHz and 1 GHz . The discrimina- tor time walk effect is compensated by time-over-threshold discriminators connected to an array of 360 dual TDC channels. The TDCpix processes up to 210 Mhits = s and provides the hit data without the need of a trigger in a continuous data stream via four 3.2 Gb = s serialisers. Under test since January 2014, the TDCPix chip is fully functional and shows excellent performance

Electrochemistry as a Powerful Tool for Investigations of Antineoplastic Agents: A Comprehensive Review

Cancer is most frequently treated with antineoplastic agents (ANAs) that are hazardous to patients undergoing chemotherapy and the healthcare workers who handle ANAs in the course of their duties. All aspects related to hazardous oncological drugs illustrate that the monitoring of ANAs is essential to minimize the risks associated with these drugs. Among all analytical techniques used to test ANAs, electrochemistry holds an important position. This review, for the first time, comprehensively describes the progress done in electrochemistry of ANAs by means of a variety of bare or modified (bio)sensors over the last four decades (in the period of 1982–2021). Attention is paid not only to the development of electrochemical sensing protocols of ANAs in various biological, environmental, and pharmaceutical matrices but also to achievements of electrochemical techniques in the examination of the interactions of ANAs with deoxyribonucleic acid (DNA), carcinogenic cells, biomimetic membranes, peptides, and enzymes. Other aspects, including the enantiopurity studies, differentiation between single-stranded and double-stranded DNA without using any label or tag, studies on ANAs degradation, and their pharmacokinetics, by means of electrochemical techniques are also commented. Finally, concluding remarks that underline the existence of a significant niche for the basic electrochemical research that should be filled in the future are presented.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Micro and Nano Engineerin

Electrochemical behavior of cocaine cutting agents at the polarized liquid-liquid interface

In this work, we have used cyclic voltammetry to investigate the interfacial behavior of cocaine cutting agents at the electrified liquid-liquid interface formed between a solution of the water and 1,2-dichloroethane phases. Among 27 chemical species used to adulterate cocaine street samples, only 8 were detectable in the available potential window. These include procaine, lidocaine, levamisole, hydroxyzine, caffeine, phenylethylamine, diltiazem, and diphenhydramine. From the calibration curves obtained using voltammetric data, we have extracted the electroanalytical parameters such as detection sensitivities, limits of detection, and limits of quantifications. Also, for each electrochemically active drug, we have calculated diffusion coefficients and plotted the ion partition and concentration fraction diagrams. All this information is discussed in a view of the cocaine sensors development focused on its detection from demanding matrix defined by the street samples composition.Resources & RecyclingChemE/Chemical Engineerin

GigaTracker, the NA62 Beam Tracker

The GigaTracker measures the momentum, the direction and the crossing time of all the NA62 secondary beam particles. It is composed of three hybrid silicon pixel stations and four achromatic magnets. All the stations have a rate capability above 750 MHz, a single hit time resolution better than 200 ps and a thickness less than 0.5 % of X = X 0 . The stations’ sensor is read out by ten custom TDCpix ASICs. An innovative microchannel cooling solution is used to keep the sensor temperature below 0 °C. The stations are operated in vacuum and are easily swappabl

GigaTracker, a Thin and Fast Silicon Pixels Tracker

GigaTracker, the NA62’s upstream spectrometer, plays a key role in the kinematically constrained background suppression for the study of the K + ! p + n ̄ n decay. It is made of three independent stations, each of which is a six by three cm 2 hybrid silicon pixels detector. To meet the NA62 physics goals, GigaTracker has to address challenging requirements. The hit time resolution must be better than 200 ps while keeping the total thickness of the sensor to less than 0.5 mm silicon equivalent. The 200 μm thick sensor is divided into 18000 300 μm 300 μm pixels bump-bounded to ten independent read-out chips. The chips use an end-of-column architecture and rely on time-over- threshold discriminators. A station can handle a crossing rate of 750 MHz. Microchannel cooling technology will be used to cool the assembly. It allows us to keep the sensor close to 0 C with 130 μm of silicon in the beam area. The sensor and read-out chip performance were validated using a 45 pixel demonstrator with a laser test setup and during a test beam. The time resolution was found to be better than 175 ps, well within the specification

Operational experience with the NA62 Gigatracker

The Gigatracker is a hybrid silicon pixel detector developed for the NA62 experiment at CERN, which aims at measuring the branching fraction of the ultra-rare kaon decay K + → π + ν ν at the CERN SPS. The detector has to track particles in a 75 GeV/c hadron beam with a flux reaching 1.3 MHz/mm 2 and provide single-hit timing with better than 200 ps r.m.s. resolution for a total material budget of less than 0.5% X 0 per station. The tracker comprises three 61 × 27 mm 2 stations installed in vacuum (about 10 − 6 mbar) and cooled with liquid C 6 F 14 circulating through micro- channels etched inside few hundred of microns thick silicon plates. Each station is composed of a 200 μ m thick planar silicon sensor bump-bonded to 2 × 5 custom 100 μ m thick ASIC, called TDCpix. Each chip contains 40 × 45 asynchronous pixels, each 300 × 300 μ m 2 and is instrumented with 720 time-to-digital converter channels with 100 ps bin. In order to cope with the high rate, the TDCpix is equipped with four 3.2 Gb/s serializers sending out the data. Detector description, operational experience and results from the NA62 experimental runs will be presented