Search results for "Anode"

One-stage periodical anodic-cathodic double pulse deposition of nanocomposite materials. Application to Prussian Blue/polypyrrole film coated electro…

2014

Abstract Novel electrochemical method of one-stage deposition of composite films on electrode surface has been proposed. The procedure includes a periodical series of potentiostatic or galvanostatic pulses of alternative polarity imposed at electrode in contact with a mixture of two solute precursors, one of which is able to generate a solid phase under its electrooxidation while another one is transformed into another solid phase under its electroreduction. Parameters of anodic and cathodic pulses (potential or current, pulse duration) may be chosen independently from one another, their relation allows one to vary the relative contents of components in the deposited composite. Thickness of…

Exciton quenching by diffusion of 2,3,5,6-tetrafluoro-7,7’,8,8’-tetra cyano quino dimethane and its consequences on joule heating and lifetime of org…

2013

In this Letter, the effect of F(4)-TCNQ insertion at the anode/hole transport layer (HTL) interface was studied on joule heating and the lifetime of organic light-emitting diodes (OLEDs). Joule heating was found to reduce significantly (pixel temperature decrease by about 10 K at a current density of 40 mA/cm(2)) by this insertion. However, the lifetime was found to reduce significantly with a 1 nm thick F(4)-TCNQ layer, and it improved by increasing the thickness of this layer. Thermal diffusion of F(4)-TCNQ into HTL leads to F(4)-TCNQ ionization by charge transfer, and drift of these molecules into the emissive layer caused faster degradation of the OLEDs. This drift was found to reduce w…

Radiation engineering of functional biomaterials: from smart hydrogels to theragnostic nanodevices

2009

Semipermeable membrane to retain platinum atoms in the electrodeposition process of alpha spectrometry sources

1998

Abstract In earlier work alpha sources electrodeposited on stainless steel backings were analyzed by X-ray fluorescence (XRF) and Rutherford backscattering spectrometry (RBS) finding that during the electrodeposition process large quantities of platinum from the anode were deposited on the cathode surface jointly with the actinides. In the present work, a method to retain platinum atoms using an electrodeposition cell with a semipermeable membrane located between anode and cathode is proposed and tested. The XRF and RBS of alpha sources electrodeposited using this method show that there is less platinum on the stainless steel backing, thereby improving the quality of sources to be measured …

A selective microscale x-ray fluorescence analyzing method for determination of trace elements

1973

Abstract A new selective X-ray fluorescence analyzing method for trace element determination has been developed. In this method each trace element is measured independently. The excitation source is an X-ray tube that has a changeable anode and a variable high voltage. The exciting radiation is shaped with critical absorbers. The sample is viewed at backward angles through an absorber to reduce backscattered radiation. The estimated accuracy of this method is of the order of 10 per cent in thesub-ppm range of trace element concentration in organic samples. Measurement times are of the order of a few minutes.

Crosslinking of poly(vinylpyrrolidone) activated by electrogenerated hydroxyl radicals: a first step towards a simple and cheap synthetic route of na…

2016

A facile electrosynthesis route for the preparation of polymer nanogels based on the in situ production of hydroxyl radicals is reported for the first time. Electro-Fenton process with continuous H2O2 electrogeneration and Fe2+ regeneration performs better than electro-oxidation with a boron-doped diamond or dimensionally stable anode for promoting crosslinking of poly(vinylpyrrolidone). Keywords: Electrogenerated hydroxyl radicals, BDD, DSA, Electro-Fenton, Polymer modification, Nanogel

Mechanically stable metal layers for ohmic and blocking contacts on CdZnTe detectors by electroless deposition

2015

CdZnTe detectors are commonly exploited for the detection of gamma rays. However, obtaining mechanical stable, low noise contacts on CdZnTe is still an issue. In particular, ohmic contacts would be preferable for high flux applications. In this work, we show that it is possible to obtain mechanical stable gold contacts by electroless deposition in methanol solution. Moreover, we show that electroless deposited nickel contacts are also mechanical stable and are good candidates for the realization of ohmic contacts on high resistivity CdZnTe crystals.

Charge carrier transport mechanisms in CdZnTe detectors grown by the vertical Bridgman technique

2016

In this work, we report on the results of electrical characterization of CdZnTe (CZT) detectors, with gold electroless contacts, grown by the boron oxide encapsulated vertical Bridgman technique (B-VB), currently produced at IMEM-CNR (Parma, Italy). The detectors, with different thicknesses (1 and 2.5 mm), have the same electrode layout: the anode is a central electrode (2 x 2 mm(2)) surrounded by a guard ring electrode. The cathode is a planar electrode covering the detector surface (4.1 x 4.1 mm(2)). Current-voltage (I-V) characteristics were measured at different temperatures in order to study the charge transport and the electrical properties. These detectors were compared with the trav…

The influence of aluminium cations on electrocarboxylation processes in undivided cells with Al sacrificial anodes

2005

Abstract The influence of Al cations on the electrochemical carboxylation of acenaphthylene ( 1 ), benzophenone ( 2 ), 6-methoxy-2-acetonaphthone ( 3 ), and benzyl chloride ( 4 ) has been investigated in dimethylformamide at a glassy carbon cathode. The Al 3+ ions were either added at the beginning of the experiment or were released from the anode during electrocarboxylation. It has been found that when Al cations are added to the reaction medium, they strongly influence the reduction process, in most cases leading to a complete change of the mechanism. For example, in the case of 1 , the radical anion ( 1 − ) formed upon 1e − reduction rapidly reacts with Al 3+ to give an Al(III) adduct, w…

Extracorporeal Stimulation of Sacral Nerve Roots for Observation of Pelvic Autonomic Nerve Integrity: Description of a Novel Methodological Setup.

2017

Introduction: Neurophysiologic monitoring can improve autonomic nerve sparing during critical phases of rectal cancer surgery. Objectives: To develop a system for extracorporeal stimulation of sacral nerve roots. Methods: Dedicated software controlled a ten-electrode stimulation array by switching between different electrode configurations and current levels. A built-in impedance and current level measurement assessed the effectiveness of current injection. Intra-anal surface electromyography (sEMG) informed on targeting the sacral nerve roots. All tests were performed on five pig specimens. Results: During switching between electrode configurations, the system delivered 100% of the set cur…