scholarly journals Aqueous phenol and ethylene glycol solutions in electrohydrodynamic liquid bridging

2011 ◽  
Vol 9 (3) ◽  
pp. 391-403 ◽  
Author(s):  
Mathias Eisenhut ◽  
Xinghua Guo ◽  
Astrid Paulitsch-Fuchs ◽  
Elmar Fuchs
Keyword(s):  
Mass Transport ◽  
Ethylene Glycol ◽  
Bisphenol A ◽  
Anodic Oxidation ◽  
High Voltage ◽  
Electrochemical Behavior ◽  
Pure Water ◽  
Passivation Layer ◽  
Mass Transfers ◽  
Electrophoretic Transport

AbstractThe formation of aqueous bridges containing phenol and ethylene glycol as well as bisphenol-A, hydrochinone and p-cresol under the application of high voltage DC (“liquid bridges”) is reported. Detailed studies were made for phenol and glycol with concentrations from 0.005 to 0.531 mol L−1. Conductivity as well as substance and mass transfers through these aqueous bridges are discussed and compared with pure water bridges. Previously suggested bidirectional mass transport is confirmed for the substances tested. Anodic oxidation happens more efficiently when phenol or glycol are transported from the cathode to the anode since in this case the formation of a passivation layer or electrode poisoning are retarded by the electrohydrodynamic (EHD) flow. The conductivity in the cathode beaker decreases in all experiments due to electrophoretic transport of naturally dissolved carbonate and bicarbonate to the anode. The observed electrochemical behavior is shortly discussed and compared to known mechanisms.

scholarly journals Comparative Study of Ag Nanostructures: Molecular Simulations, Electrochemical Behavior, and Antibacterial Effect

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Álvaro de Jesús Ruíz-Baltazar ◽  
Simón Yobanny Reyes-López ◽  
D. Larrañaga ◽  
R. Pérez
Keyword(s):  
Cyclic Voltammetry ◽  
Ethylene Glycol ◽  
Comparative Study ◽  
Sodium Borohydride ◽  
Electrochemical Behavior ◽  
Antibacterial Effect ◽  
Chemical Reduction ◽  
Molecular Simulations ◽  
The Other ◽  
E Coli

Nanoparticles of Ag with different sizes and structures were obtained and studied. Two methods for reductions of Ag ions were employed, chemical reduction by sodium borohydride and ethylene glycol. Cuboctahedral and icosahedral structures were obtained. Molecular simulations were carried out in order to evaluate the reactivity of both structures. On the other hand, the electrochemical activity and antibacterial effect (E. coli) of the cuboctahedral and icosahedral structures were measured experimentally. The results obtained by molecular simulation, cyclic voltammetry, and antibacterial effect were compared and discussed in this work.

Electrochemical studies of the Pb2+/Pb(Hg) system in aqueous and aqueous ethylene glycol solutions

1979 ◽  
Vol 57 (14) ◽  
pp. 1801-1803 ◽  
Author(s):  
Tibor Rabockai
Keyword(s):  
Aqueous Solution ◽  
Ethylene Glycol ◽  
Organic Solvent ◽  
Electrochemical Behavior ◽  
Experimental Error ◽  
Electrochemical Studies ◽  
Temperature Range ◽  
All Solutions ◽  
Aqueous Ethylene Glycol ◽  
Current Reversal

The electrochemical behavior of the Pb2+/Pb(Hg) system in aqueous and aqueous ethylene glycol solutions is studied in the temperature range of 20.0 to 50.0 °C by means of current reversal chronopotentiometry. It is shown that the reduction of Pb2+ ion is reversible and that kinetic or catalytic complications are not present. The value of dE1/2/dT is −0.6 mV/deg in the aqueous solution and −0.5 mV/deg in the solution with 56% (w/w) or higher concentrations of the organic solvent. In the above concentration range of ethylene glycol the activation energies of diffusion and viscosity vary from 4.3 × 103 to 7.2 × 103 cal mol−1 and from 3.7 × 103 to 6.7 × 103 cal mol−1, respectively. For all solutions the solvodynamic mean radius of the diffusing species remains constant within the experimental error, suggesting that the diffusing species is always the hydrated Pb2+ ion.

Measurement and Modeling of Latent Heat Release During Freezing of Aqueous Solutions in a Small Container

2000 ◽  
Author(s):  
Ramachandra V. Devireddy ◽  
John C. Bischof ◽  
Perry H. Leo ◽  
John S. Lowengrub
Keyword(s):  
Mass Transport ◽  
Heat Release ◽  
Latent Heat ◽  
Pure Water ◽  
Heat Of Fusion ◽  
Freezing Process ◽  
Latent Heat Release ◽  
Aqueous Systems ◽  
Heat And Mass Transport ◽  
Latent Heat Of Fusion

Abstract The latent heat of fusion, ΔHf of a cryobiological medium (a solute laden aqueous solution) is a crucial parameter in the cryopreservation process. The latent heat has often been approximated by that of pure water (∼ 335 mJ/mg). However, recent calorimetric (DSC - Pyris 1) measurements suggest that the actual magnitude of latent heat of fusion during freezing of solute laden aqueous systems is far less. Fourteen different pre-nucleated solute laden aqueous systems (NaCl-H2O, Phosphate Buffered Saline or PBS, serum free RPMI, cell culture medium, glycerol and Anti Freeze Protein solutions) were found to have significantly lower ΔHf than that of pure water (Devireddy and Bischof, 1998). In the present study additional calorimetric experiments are performed at 1, 5 and 20 °C/min in five representative cryobiological media (isotonic or 1× NaCl-H2O, 10× NaCl-H2O, 1× PBS, 5× PBS and 10× PBS) to determine the kinetics of ice crystallization. The temperature (T) and time (t) dependence of the latent heat release is measured. The experimental data shows that at a fixed temperature, the fraction of heat released at higher cooling rates (5 and 20 °C/min) is lower than at 1 °C/min for all the solutions studied. We then sought a simple model that could predict the experimentally measured behavior and examined the full set of heat and mass transport equations during the freezing process in a DSC sample pan. The model neglects the interaction between the growing ice crystals and is most appropriate during the early stages of the freezing process. An examination of the coefficients in the heat and mass transport equations shows that heat transport occurs much more rapidly than solute transport. Hence, the full model reduces to one in which the temperature profile is constant in space while the solute concentration profile obeys the full time and space dependent diffusion equation. The model reveals the important physical parameters controlling the mass transport at the freezing interface and further elucidates the experimental results, i.e. the temperature and time dependence of the latent heat release.

Electrochemical Behavior of High-Voltage LiNi0.5Mn1.5O4-xFx Electrodes at Elevated Storage Temperature

2008 ◽  
Vol 24 (01) ◽  
pp. 165-170
Author(s):  
DU Guo-Dong ◽  
◽  
◽  
NULI Yan-Na ◽  
FENG Zhen-Zhen ◽  
...  
Keyword(s):  
High Voltage ◽  
Electrochemical Behavior ◽  
Storage Temperature

scholarly journals Analysis of the Anodic Oxidation of a-Si:H in Ethylene Glycol Solution by a Current Interrupter Technique.

1992 ◽  
Vol 43 (4) ◽  
pp. 335-339 ◽  
Author(s):  
Masamitsu YUGA ◽  
Noboru AKAZAWA ◽  
Tamae YAMAZAKI ◽  
Masanori OHYAMA
Keyword(s):  
Ethylene Glycol ◽  
Anodic Oxidation ◽  
Glycol Solution ◽  
A Current

Formation of Anodic Oxide Nanotubes in H2O2 - Fluoride Ethylene Glycol Electrolyte as Template for Electrodeposition of α-Fe2O3

2013 ◽  
Vol 832 ◽  
pp. 333-337 ◽  
Author(s):  
Zainovia Lockman ◽  
Dede Miftahul Anwar ◽  
Monna Rozana ◽  
Syahriza Ismail ◽  
Ehsan Ahmadi ◽  
...  
Keyword(s):  
Oxide Film ◽  
Ethylene Glycol ◽  
Pore Size ◽  
Surface Structure ◽  
Anodic Oxidation ◽  
Chloride Solution ◽  
Anodic Oxide ◽  
Nanoporous Structure ◽  
20 Nm

Anodic oxidation of titanium (Ti), zirconium (Zr) and niobium (Nb) foils in fluoride ethylene glycol (EG) added to it 1 H2O2 as oxidant was done to produce oxide film with nanostructures at 40 V. Whilst arrays of aligned nanotubes were successfully formed on the surface of Ti and Zr respectively, anodic Nb2O5 was found to consist of nanoporous structure with pore size of ~ 20 nm. Despite long nanotubes were formed on both Ti (2 μm) and Zr (3 μm), the surface of the nanotubes suffered from severe dissolution, thinning the wall and collapsing them. Well defined, ordered surface structure of the nanotubes is required as they will be used as template for subsequent deposition of nanoparticles. This was achieved when Ti anodised in 5 ml H2O2 fluoride EG. With excess H2O2 etching at the surface occur more uniformly forming homogenous surface structure. α-Fe2O3 were then electrodeposited on this surface at-3 V from chloride solution and the mode of formation is believed to be due to electrogeneration of base at the surface of the TiO2.

Understanding the impact of calcination time of high-voltage spinel Li1+Ni0.5Mn1.5O4 on structure and electrochemical behavior

2019 ◽  
Vol 325 ◽  
pp. 134901 ◽  
Author(s):  
Johannes Betz ◽  
Laura Nowak ◽  
Jan-Paul Brinkmann ◽  
Peer Bärmann ◽  
Marcel Diehl ◽  
...  
Keyword(s):  
High Voltage ◽  
Electrochemical Behavior ◽  
Calcination Time ◽  
The Impact
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