Search results for "Electrode"

Metallic Nanoparticles Linked to Molecular Switches as Signal Processing Devices

2009

We explore theoretically the use of nanoscale switches whose conductance can be varied between two states by an external stimulus to implement signal processing devices. The building block is formed by a metallic nanoparticle linked to two electrodes by an organic ligand and a molecular switch. The system implementation exploits the sharp current resonance of the system that occurs when the frequencies of the applied potential and the induced variation on the switch conductance coincide.

Device variability and circuit redundancy in signal processing based on nanoswitches

2009

Signal processing based on molecular switches whose conductance can be tuned by an external stimulus between two (on and off) states has been proposed recently (Cervera et al 2008 J. Appl. Phys. 104 084317). The basic building block is a metal nanoparticle linked to two electrodes by an organic ligand and a nanoswitch. The net charge delivered by this nanostructure exhibits a sharp resonance when the alternating potential applied between the electrodes has the same frequency as the periodic variation between the on and off conductance states induced on the nanoswitch. This resonance can be used to process an external signal by selectively extracting the weight of the different harmonics. Ho…

Problems Involved in the Measurement of Microcirculation by Means of Microelectrodes

1973

Until now, the interpretation of local wash-out curves, measured by means of microelectrodes and using hydrogen as diffusible indicator, is an unsettled problem. It has been shown, that even the simultaneous measurement by means of a surface-multiwire-Pt-microelectrode at the isolated and hemoglobin-free perfused rat liver yields different wash-out curves (4). These differences occur with regard to the height of the curves as well as to the moment, when the maximum of the indicator’s concentration is seen by the microelectrode. Fig.1 represents four simultaneously recorded curves. The difference in sensitivity of each micro-electrode has been compensated by a computer. The fast curve corres…

Behavioral and hippocampal evoked responses in an auditory oddball situation when an unconditioned stimulus is paired with deviant tones in the cat: …

1995

Event-related potentials (ERP) in the areas CA1, CA3 and dentate fascia (Df) of the hippocampal formation were recorded during an oddball situation in the cat. A rewarding electrical stimulation of the lateral hypothalamus (US) was paired with deviant tones (2500 Hz) that occurred randomly in a series of the standard tones (2000 Hz) given to the left ear. In addition to developing orienting head movements to the side of the deviant tones, an increase in the amplitude of parallel hippocampal ERPs was observed. Both the behavioral and neural responses appeared not until a 50 ms latency range. Furthermore, time-amplitude characteristics of the ERPs corresponded to time-acceleration characteris…

Old Principle of Liquid Ion-Impedance Spectrometry (Particularly in Milk) Realised by New Components

2020

Abstract Ion impedance spectrometry enables detection of the concentrations of multiple chemical compositions in a weak solution, usually if only part of a complex signal is used and the frequency is not swept. Prior to the method described in this paper, ion impedance required rather sophisticated electronics to collect the results from an instrument, as well as the electrode polarisation minimising. We elaborated and tested circuitry that uses the newest electronics components for a chemical analysis instrument designed according to a principle patented in Latvia (No. SU-1021440A), year 1981. The newly improved ion impedance spectrometry apparatus is suited for accurate measurement of ion…

Synergistic effects of multiwalled carbon nanotubes and Al on the electrochemical hydrogen storage properties of Mg2Ni-type alloy prepared by mechani…

2012

Abstract Mg 2− x Al x Ni ( x  = 0, 0.25) electrode alloys with and without multiwalled carbon nanotubes (MWCNTs) have been prepared by mechanical alloying (MA) under argon atmosphere at room temperature using a planetary high-energy ball mill. The microstructures of synthesized alloys are characterized by XRD, SEM and TEM. XRD analysis results indicate that Al substitution results in the formation of AlNi-type solid solution that can interstitially dissolve hydrogen atoms. In contrast, the addition of MWCNTs hardly affects the XRD patterns. SEM observations show that after co-milling with 5 wt. % MWCNTs, the particle sizes of both Mg 2 Ni and Mg 1.75 Al 0.25 Ni milled alloys are decreased e…

Toward mass producible ordered bulk heterojunction organic photovoltaic devices.

2012

A strategy to fabricate nanostructured poly(3-hexylthiophene) (P3HT) films for organic photovoltaic (OPV) cells by a direct transfer method from a reusable soft replica mold is presented. The flexible polyfluoropolyether (PFPE) replica mold allows low-pressure and low- temperature process condition for the successful transfer of nanostructured P3HT films onto PEDOT/PSS-coated ITO substrates. To reduce the fabrication cost of masters in large area, we employed well-ordered anodic aluminum oxide (AAO) as a template. Also, we provide a method to fabricate reversed nanostructures by exploiting the self-replication of replica molds. The concept of the transfer method in low temperature with a fl…

Nanotransducers on printed circuit boards by rational design of high-density, long, thin and untapered ZnO nanowires

2018

Abstract Nanotransducers can offer crucial advantages in comparison with conventional sensors and actuators. However, interfacing and packaging nanostructures into complete electronic systems is very complex. Here we describe a wet chemical method for cointegrating arrays of ZnO nanowires into systems on printed circuit boards (PCBs). First, we deposit on the PCB a MnOOH layer for reproducibly increasing the nanowires density. Afterwards, we numerically demonstrate that the ligand ethylenediamine, at the isoelectric point of the ZnO nanowires tips, can effectively control, at very low concentrations, both zinc speciation and supersaturation in the nutrient solution. Accordingly, we combine …

Composites of Graphene with Large Aromatic Molecules

2009

Formation of ZnO nanowires by anodization under hydrodynamic conditions for photoelectrochemical water splitting

2020

[EN] The present work studies the influence of hydrodynamic conditions (from 0 to 5000 rpm) during Zn anodization process on the morphology, structure and photoelectrocatalytic behavior of ZnO nanostructures. For this purpose, analysis with Confocal Laser-Raman Spectroscopy, Field Emission Scanning Electron Microscope (FE-SEM) and photoelectrochemical water splitting tests were performed. This investigation reveals that hydrodynamic conditions during anodization promoted the formation of ordered ZnO nanowires along the surface that greatly enhance its stability and increases the photocurrent density response for water splitting in a 159% at the 5000 rpm electrode rotation speed.