Diffusion-Limited Extraction of Organic Ions by a Track-Membrane Interfaced Vacuum Inlet

2003 ◽  
Vol 9 (3) ◽  
pp. 187-193 ◽  
Author(s):  
V.V. Gridin ◽  
T.K. Kim ◽  
A. Bekkerman ◽  
V. Bulatov ◽  
K.-H. Jung ◽  
...  
Keyword(s):  
Ambient Pressure ◽  
High Mobility ◽  
Solute Concentration ◽  
Charged Species ◽  
Ion Injection ◽  
Diffusion Limited ◽  
Track Membranes ◽  
Charge Extraction ◽  
Organic Solutions ◽  
State Charge

Glycerol-wetted track membranes (polyethylene terephthalate) were used to interface a low-vacuum facility (∼ 10−3 Torr) to an ambient pressure liquid analyte. High-field charge extraction conditions were routinely maintained between the liquid samples and a grid collector. The latter was positioned just near to the vacuum-facing side of such membranes. Upon establishing a steady-state charge-extraction regime, the collector currents were monitored and recorded at various solute concentration levels. The collector currents, which depend on solute concentration, were found to agree with recent theoretical treatments of such processes. Both positively- and negatively-charged species from organic solutions were routinely extracted. Ion injection for the low- and the high-mobility species has favored the diffusion-limited and the evaporation-limited schemes, respectively. Variable concentrations of 1-pyrenoyl-methylpyridinium bromide as well as naphthylacetic and anthracenecarboxylic acids in glycerol were used.

Time resolved magnetic modulation of ion recombination in organic solutions: spin motion in radical ion pairs

1977 ◽  
Vol 55 (11) ◽  
pp. 2102-2106 ◽  
Author(s):  
Jean Klein ◽  
René Voltz
Keyword(s):  
Solid Solutions ◽  
Organic Liquid ◽  
Ion Pairs ◽  
Lattice Relaxation ◽  
Solute Concentration ◽  
High Energy ◽  
Spin Lattice Relaxation ◽  
Time Resolved ◽  
Spin Lattice ◽  
Organic Solutions

The evolution of the singlet character of correlated ion radical pairs, prepared by high energy impact (3 particles) in organic liquid and solid solutions, is monitored by nanosecond time resolved solute recombination fluorescence. Results obtained show that the relative variations [IB(t) − I0(t)]/I0(t) of the luminescence intensity in presence IB(t) and in absence I0(t) of magnetic fields (B < 5 kG) decrease exponentially with time, according to a field and solute concentration dependent rate, in liquid but not in solid solutions; in the case of 2b PPD as solute, a damped oscillating component could be observed. The results are interpreted in terms of hyperfine interaction induced coherent singlet–triplet mixing and of field and solute concentration dependent spin–lattice relaxation.

Growth of gas bubbles in the biotissues with convective acceleration

2014 ◽  
Vol 07 (06) ◽  
pp. 1450072 ◽  
Author(s):  
S. A. Mohammadein ◽  
K. G. Mohamed
Keyword(s):  
Concentration Distribution ◽  
Bubble Dynamics ◽  
Ambient Pressure ◽  
Growth Stages ◽  
Gas Bubble ◽  
Bubble Motion ◽  
Dissolved Gas ◽  
Diffusion Limited ◽  
The Mathematical Model ◽  
Dominant Parameter

This paper presents formulae and explanation about the growth of a convective gas bubble in the blood and other tissues of divers who surface too quickly, concentration distribution around the growing bubble is also presented. The formulae are valid all over the growth stages, i.e. under variable ambient pressure while the diver is ascending, and under constant ambient pressure at diving stops or at sea level. The mathematical model is solved analytically by using the method of combined variables. The growth process is affected by tissue diffusivity, concentration constant and the initial void fraction, which is the dominant parameter. Results show that, the time of the complete growth, in the convective growth model, is shorter than those earlier presented by Mohammadein and Mohamed [Concentration distribution around a growing gas bubble in tissue, Math. Biosci.225(1) (2010) 11–17] and Srinivasan et al. [Mathematical models of diffusion-limited gas bubble dynamics in tissue, J. Appl. Physiol.86 (1999) 732–741] for the growth of a stationary gas bubble, this explains the effect of bubble motion on consuming the oversaturated dissolved gas from the tissue into growing bubble which leads to increment in the growth rate to be more than those presented in the previous stationary models.

scholarly journals Surface State Charge Dynamics of a High-Mobility Three-Dimensional Topological Insulator

2011 ◽  
Vol 107 (13) ◽  
Author(s):  
Jason N. Hancock ◽  
J. L. M. van Mechelen ◽  
Alexey B. Kuzmenko ◽  
Dirk van der Marel ◽  
Christoph Brüne ◽  
...  
Keyword(s):  
Topological Insulator ◽  
Surface State ◽  
Three Dimensional ◽  
High Mobility ◽  
Charge Dynamics ◽  
State Charge

Publisher’s Note: Surface State Charge Dynamics of a High-Mobility Three-Dimensional Topological Insulator [Phys. Rev. Lett.107, 136803 (2011)]

2011 ◽  
Vol 107 (14) ◽  
Author(s):  
Jason N. Hancock ◽  
J. L. M. van Mechelen ◽  
Alexey B. Kuzmenko ◽  
Dirk van der Marel ◽  
Christoph Brüne ◽  
...  
Keyword(s):  
Topological Insulator ◽  
Surface State ◽  
Three Dimensional ◽  
High Mobility ◽  
Charge Dynamics ◽  
State Charge

Multichannel extraction of charged species from liquid with use of track membranes

1997 ◽  
Vol 40-41 ◽  
pp. 615-620 ◽  
Author(s):  
A.A. Balakin ◽  
A.F. Dodonov ◽  
L.I. Novikova ◽  
V.L. Talrose
Keyword(s):  
Charged Species ◽  
Track Membranes

scholarly journals Physical determinants of vesicle mobility and supply at a central synapse

eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
Jason Seth Rothman ◽  
Laszlo Kocsis ◽  
Etienne Herzog ◽  
Zoltan Nusser ◽  
Robin Angus Silver
Keyword(s):  
High Mobility ◽  
Mossy Fibre ◽  
Ribbon Synapses ◽  
Diffusion Limited ◽  
Replenishment Rate ◽  
Central Synapse ◽  
Vesicle Mobility ◽  
Constrained Models ◽  
Central Synapses ◽  
Ribbon Structures

Encoding continuous sensory variables requires sustained synaptic signalling. At several sensory synapses, rapid vesicle supply is achieved via highly mobile vesicles and specialized ribbon structures, but how this is achieved at central synapses without ribbons is unclear. Here we examine vesicle mobility at excitatory cerebellar mossy fibre synapses which sustain transmission over a broad frequency bandwidth. Fluorescent recovery after photobleaching in slices from VGLUT1Venus knock-in mice reveal 75% of VGLUT1-containing vesicles have a high mobility, comparable to that at ribbon synapses. Experimentally constrained models establish hydrodynamic interactions and vesicle collisions are major determinants of vesicle mobility in crowded presynaptic terminals. Moreover, models incorporating 3D reconstructions of vesicle clouds near active zones (AZs) predict the measured releasable pool size and replenishment rate from the reserve pool. They also show that while vesicle reloading at AZs is not diffusion-limited at the onset of release, diffusion limits vesicle reloading during sustained high-frequency signalling.

scholarly journals Two-dimensional hole gas in organic semiconductors

2020 ◽  
Author(s):  
Naotaka Kasuya ◽  
Junto Tsurumi ◽  
Toshihiro Okamoto ◽  
Shun Watanabe ◽  
Jun Takeya
Keyword(s):  
Organic Semiconductors ◽  
Ambient Pressure ◽  
High Mobility ◽  
Electronic States ◽  
Two Dimensional ◽  
Dimensional Electron ◽  
Metal Insulator ◽  
Semiconductor Interfaces ◽  
Dimensional Electron Gas ◽  
Low Dimensional

Abstract A highly conductive metallic gas that is quantum mechanically confined at a solid-state interface is an ideal platform to explore nontrivial electronic states that are otherwise inaccessible in bulk materials. Although two-dimensional electron gas (2DEG) has been realized in conventional semiconductor interfaces, examples of two-dimensional hole gas (2DHG), which is the counter analogue of 2DEG, are still limited. Here, we report the observation of a 2DHG in solution-processed organic semiconductors in conjunction with an electric double-layer using ionic liquids. A molecularly flat single crystal of high mobility organic semiconductors serves as a defect-free interface that facilitates two-dimensional confinement of high-density holes. Remarkably low sheet resistance of 6 kΩ and high hole gas density of 1014 cm14 result in a metal-insulator transition at ambient pressure. The measured degenerated holes in the organic semiconductors provide a broad opportunity to tailor low-dimensional electronic states using molecularly engineered heterointerfaces.

Analytical Electron Microscopy of Surface-Modified Ceramics

1985 ◽  
Vol 43 ◽  
pp. 276-279
Author(s):  
P. S. Sklad
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Theoretical Models ◽  
Ceramic Materials ◽  
Solute Concentration ◽  
Second Phase ◽  
Analytical Electron ◽  
Implantation Techniques ◽  
Lattice Damage ◽  
Surface Modified

Over the past several years, it has become increasingly evident that materials for proposed advanced energy systems will be required to operate at high temperatures and in aggressive environments. These constraints make structural ceramics attractive materials for these systems. However it is well known that the condition of the specimen surface of ceramic materials is often critical in controlling properties such as fracture toughness, oxidation resistance, and wear resistance. Ion implantation techniques offer the potential of overcoming some of the surface related limitations.While the effects of implantation on surface sensitive properties may be measured indpendently, it is important to understand the microstructural evolution leading to these changes. Analytical electron microscopy provides a useful tool for characterizing the microstructures produced in terms of solute concentration profiles, second phase formation, lattice damage, crystallinity of the implanted layer, and annealing behavior. Such analyses allow correlations to be made with theoretical models, property measurements, and results of complimentary techniques.

Point Defect Absorption and Dislocation Loop Formation at Grain Boundaries in Hvem-Irradiated Zr and Its Alloys:1. Influence of Solute Addition

1985 ◽  
Vol 43 ◽  
pp. 350-351
Author(s):  
R.A. Herring ◽  
M. Griffiths ◽  
M.H Loretto ◽  
R.E. Smallman
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Point Defect ◽  
Reactor Core ◽  
Solute Concentration ◽  
Nuclear Industry ◽  
Dislocation Loops ◽  
Loop Formation ◽  
Component Material ◽  
Impurity Interaction

Because Zr is used in the nuclear industry to sheath fuel and as structural component material within the reactor core, it is important to understand Zr's point defect properties. In the present work point defect-impurity interaction has been assessed by measuring the influence of grain boundaries on the width of the zone denuded of dislocation loops in a series of irradiated Zr alloys. Electropolished Zr and its alloys have been irradiated using an AEI EM7 HVEM at 1 MeV, ∼675 K and ∼10-6 torr vacuum pressure. During some HVEM irradiations it has been seen that there is a difference in the loop nucleation and growth behaviour adjacent to the grain boundary as compared with the mid-grain region. The width of the region influenced by the presence of the grain boundary should be a function of the irradiation temperature, dose rate, solute concentration and crystallographic orientation.

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