Influence of Diluent Concentration in Localized High Concentration Electrolytes: Elucidation of Hidden Diluent-Li+ Interactions and Li+ Transport Mechanism

2021 ◽  
Author(s):  
Saul Perez-Beltran ◽  
Xia Cao ◽  
Ji-Guang Zhang ◽  
Patrick Z El-Khoury ◽  
Perla B Balbuena
Keyword(s):  
Transport Mechanism ◽  
High Concentration ◽  
Oxidative Behavior

Localized high concentration electrolytes (LHCE) offer a viable dilution strategy for high concentration electrolytes (HCE) as the dilution process barely impacts the enhanced reductive/oxidative behavior of the HCE formulation but...

Kinetic studies on transport of PAH and other organic acids in isolated renal tubules

1965 ◽  
Vol 208 (2) ◽  
pp. 391-396 ◽  
Author(s):  
K. C. Huang ◽  
Dorothy S. T. Lin
Keyword(s):  
Organic Acids ◽  
Partition Coefficient ◽  
Transport Mechanism ◽  
Hippuric Acid ◽  
Kinetic Studies ◽  
Inhibitory Effect ◽  
Renal Tubules ◽  
High Concentration ◽  
Low Concentration ◽  
Tubular Transport

Studies were made on the uptake and washout of PAH and other organic acids in isolated renal tubules and cells at 25 C. The renal tubules accumulated PAH rapidly in the first 30-min period. Probenecid, its diethyl- and dimethyl analogues, hippuric acid, and 2,4-dinitrophenol inhibited the tubular transport of PAH competitively. A relationship between the inhibitory effect and the partition coefficient of the compound was observed; the higher the partition coefficient, the greater the inhibition. DNP was also accumulated in the isolated renal tubules. This accumulation was depressed by probenecid, indicating that DNP is probably transported by the same tubular transport mechanism for PAH and other organic acids. In washout experiments probenecid and DNP showed a biphasic action, namely, they stimulated the PAH washout in low concentration and inhibited it in high concentration However, hippuric acid, which has a low partition coefficient, demonstrated an augmentation of PAH washout even at a concentration of 2 x 10–2 m

scholarly journals Modulated Structure Determination and Ion Transport Mechanism of Oxide-Ion Conductor CeNbO4+δ

2019 ◽  
Author(s):  
Jian Li ◽  
Fengjuan Pan ◽  
Shipeng Geng ◽  
Cong Lin ◽  
Mathieu Allix ◽  
...  
Keyword(s):  
Performance Optimization ◽  
Transport Mechanism ◽  
Ionic Conduction ◽  
Excess Oxygen ◽  
High Concentration ◽  
Ion Migration ◽  
Ion Conductor ◽  
Oxide Ion Conductor ◽  
Continuous Rotation ◽  
Oxide Ion

<p>CeNbO<sub>4+δ</sub>, a family of oxygen hyperstoichiometry materials with varying oxygen contents (CeNbO<sub>4</sub>, CeNbO<sub>4.08</sub>, CeNbO<sub>4.25</sub>, CeNbO<sub>4.33</sub>) and showing mixed electronic and oxide ionic conduction, have been known for four decades. However, the oxide ionic transport mechanism has remained unclear due to the unknown atomic superstructures of CeNbO<sub>4.08</sub> and CeNbO<sub>4.33</sub>. Here, we determinate the complex superstructures of CeNbO<sub>4.08 </sub>(89 unique atoms), <a>CeNbO<sub>4.25 </sub>(75 unique atoms) and CeNbO<sub>4.33</sub> (19 unique atoms) by using recently developed continuous rotation electron diffraction (cRED) technique from nano single crystals. </a><a>The Ce cationic size contraction upon oxidation in CeNbO<sub>4+δ</sub> allows not only excess oxygen incorporation into the CeNbO<sub>4</sub> host lattice at the interstitial site within the Ce cation chains (referred to as O<sub>i</sub>), but also relaxation of the<sub> </sub>NbO<sub>n</sub> polyhedra in CeNbO<sub>4.08</sub>, CeNbO<sub>4.25</sub>, CeNbO<sub>4.33</sub> being bridged through mixed corner/edge-sharing in 3-dimentional directions. </a>Two kinds of oxide ion migration events are identified in CeNbO<sub>4.08</sub> and CeNbO<sub>4.25</sub> phases by molecular dynamic simulations, which form long-rang 3-dimensional migration pathway through the interstitial sites O<sub>i</sub> via a synergic-cooperation knock-on mechanism involving continuous breaking and reformation of Nb<sub>2</sub>O<sub>9</sub> units. However, the excess oxygen in the CeNbO<sub>4.33</sub> phase hardly migrates because of ordered distribution of high-concentration excess oxide ions. The relationship between the structure and oxide ion migration for the whole series of CeNbO<sub>4+</sub><sub>d</sub> compounds elucidated here provides a direction for the performance optimization of these compounds and the development of oxygen hyperstoichiometric materials for wide variety of applications.</p>

Effect of coinfusion of cholic acid and sulfated cholic acid on bile formation in rats

1989 ◽  
Vol 256 (1) ◽  
pp. G62-G66
Author(s):  
I. M. Yousef ◽  
B. Tuchweber ◽  
D. Mignault ◽  
A. Weber
Keyword(s):  
Toxic Effect ◽  
Bile Acids ◽  
Cholic Acid ◽  
Bile Flow ◽  
Transport Mechanism ◽  
High Concentration ◽  
Bile Formation

The effect of combined infusion of sulfated cholic acid and nonsulfated cholic acid on bile formation was investigated. The data show that the secretion of sulfated cholic acid is slower and does not share the same transport mechanism(s) as nonsulfated cholic acid. Sulfated cholic acid significantly increased bile flow and reduced the secretion of biliary phospholipids, cholesterol, and protein associated with the secretion of exogenous nonsulfated cholic acid, only when they were infused in a ratio higher than 2:1 (sulfated:nonsulfated). Thus it is concluded that sulfated bile acids may protect the liver against the toxic effect of high concentration of bile acids. The relevance of these findings to human cholestasis remains to be determined because sulfated bile acids do not predominate in serum during cholestasis.

scholarly journals Modulated Structure Determination and Ion Transport Mechanism of Oxide-Ion Conductor CeNbO4+δ

2019 ◽  
Author(s):  
Jian Li ◽  
Fengjuan Pan ◽  
Shipeng Geng ◽  
Cong Lin ◽  
Mathieu Allix ◽  
...  
Keyword(s):  
Performance Optimization ◽  
Transport Mechanism ◽  
Ionic Conduction ◽  
Excess Oxygen ◽  
High Concentration ◽  
Ion Migration ◽  
Ion Conductor ◽  
Oxide Ion Conductor ◽  
Continuous Rotation ◽  
Oxide Ion

<p>CeNbO<sub>4+δ</sub>, a family of oxygen hyperstoichiometry materials with varying oxygen contents (CeNbO<sub>4</sub>, CeNbO<sub>4.08</sub>, CeNbO<sub>4.25</sub>, CeNbO<sub>4.33</sub>) and showing mixed electronic and oxide ionic conduction, have been known for four decades. However, the oxide ionic transport mechanism has remained unclear due to the unknown atomic superstructures of CeNbO<sub>4.08</sub> and CeNbO<sub>4.33</sub>. Here, we determinate the complex superstructures of CeNbO<sub>4.08 </sub>(89 unique atoms), <a>CeNbO<sub>4.25 </sub>(75 unique atoms) and CeNbO<sub>4.33</sub> (19 unique atoms) by using recently developed continuous rotation electron diffraction (cRED) technique from nano single crystals. </a><a>The Ce cationic size contraction upon oxidation in CeNbO<sub>4+δ</sub> allows not only excess oxygen incorporation into the CeNbO<sub>4</sub> host lattice at the interstitial site within the Ce cation chains (referred to as O<sub>i</sub>), but also relaxation of the<sub> </sub>NbO<sub>n</sub> polyhedra in CeNbO<sub>4.08</sub>, CeNbO<sub>4.25</sub>, CeNbO<sub>4.33</sub> being bridged through mixed corner/edge-sharing in 3-dimentional directions. </a>Two kinds of oxide ion migration events are identified in CeNbO<sub>4.08</sub> and CeNbO<sub>4.25</sub> phases by molecular dynamic simulations, which form long-rang 3-dimensional migration pathway through the interstitial sites O<sub>i</sub> via a synergic-cooperation knock-on mechanism involving continuous breaking and reformation of Nb<sub>2</sub>O<sub>9</sub> units. However, the excess oxygen in the CeNbO<sub>4.33</sub> phase hardly migrates because of ordered distribution of high-concentration excess oxide ions. The relationship between the structure and oxide ion migration for the whole series of CeNbO<sub>4+</sub><sub>d</sub> compounds elucidated here provides a direction for the performance optimization of these compounds and the development of oxygen hyperstoichiometric materials for wide variety of applications.</p>

Effects of Anolyte Concentration on Removal of Fluorine from Contaminated Soil by Electrokinetic Treatment

2012 ◽  
Vol 518-523 ◽  
pp. 2500-2504
Author(s):  
Ming Zhou ◽  
Shu Fa Zhu ◽  
Ya Na Liu
Keyword(s):  
Removal Efficiency ◽  
Contaminated Soil ◽  
Applied Voltage ◽  
Transport Mechanism ◽  
Experimental Results ◽  
High Concentration ◽  
Electrokinetic Treatment ◽  
The Cost

A series of electrokinetic experiments were conducted on fluorine-contaminated soil with different anolyte (NaOH) concentrations in a self-made electrolyzer to investigate the effects of anolyte concentration on removal of fluorine. Experimental results showed that anolyte concentration (0.1mol L-1) was more suitable of the six anolyte concentration tested, in contrast to the removal efficiency of fluorine and the cost of the high concentration of anolyte. On this anolyte concentration that 57.75% fluorine could be removed from contaminated soil within 10 days under the applied voltage (1.0 V cm-1). The results also indicated that electromigration was a dominant transport mechanism responsible for the removal of fluorine from contaminated soil than electroosmosis.

scholarly journals Modulated structure determination and ion transport mechanism of oxide-ion conductor CeNbO4+δ

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Jian Li ◽  
Fengjuan Pan ◽  
Shipeng Geng ◽  
Cong Lin ◽  
Lukas Palatinus ◽  
...  
Keyword(s):  
Performance Optimization ◽  
Transport Mechanism ◽  
Ionic Conduction ◽  
Excess Oxygen ◽  
High Concentration ◽  
Ion Migration ◽  
Modulated Structure ◽  
Ion Conductor ◽  
Oxide Ion Conductor ◽  
Oxide Ion

Abstract CeNbO4+δ, a family of oxygen hyperstoichiometry materials with varying oxygen content (CeNbO4, CeNbO4.08, CeNbO4.25, CeNbO4.33) that shows mixed electronic and oxide ionic conduction, has been known for four decades. However, the oxide ionic transport mechanism has remained unclear due to the unknown atomic structures of CeNbO4.08 and CeNbO4.33. Here, we report the complex (3 + 1)D incommensurately modulated structure of CeNbO4.08, and the supercell structure of CeNbO4.33 from single nanocrystals by using a three-dimensional electron diffraction technique. Two oxide ion migration events are identified in CeNbO4.08 and CeNbO4.25 by molecular dynamics simulations, which was a synergic-cooperation knock-on mechanism involving continuous breaking and reformation of Nb2O9 units. However, the excess oxygen in CeNbO4.33 hardly migrates because of the high concentration and the ordered distribution of the excess oxide ions. The relationship between the structure and oxide ion migration for the whole series of CeNbO4+δ compounds elucidated here provides a direction for the performance optimization of these compounds.

Influx of Two Dipeptides, Glycylsarcosine and l-glutamyl-l-glutamic Acid, into hamster Jejunum in Vitro

1979 ◽  
Vol 56 (1) ◽  
pp. 15-23 ◽  
Author(s):  
D. M. Matthews ◽  
R. H. Gandy ◽  
E. Taylor ◽  
D. Burston
Keyword(s):  
Glutamic Acid ◽  
Brush Border ◽  
Transport Mechanism ◽  
Inhibitory Effect ◽  
The Other ◽  
Peptide Transport ◽  
High Concentration ◽  
Simple Diffusion ◽  
Diffusion Component

1. This paper reports an investigation of whether the dipeptides glycylsarcosine and l-glutamyl-l-glutamic acid share a single mediated transport mechanism into hamster jejunum, or whether one of these peptides is transported in part by a transport mechanism unavailable to the other. It describes the kinetics of influx of glycylsarcosine and of l-glutamyl-l-glutamic acid into rings of everted hamster jejunum in vitro, incubations being carried out at pH 5 in order to minimize brush-border and intra-medium hydrolysis of l-glutamyl-l-glutamic acid, so that peptide transport rather than a mixture of peptide transport and transport of free glutamic acid was studied. With glycylsarcosine, brush-border and intra-medium hydrolysis are negligibly small. 2. Estimates of the simple diffusion component in transport of each peptide were made by treating each of the substrates as a competitive inhibitor of its own mediated transport (assuming that mediated transport conforms to simple Michaelis-Menten kinetics), extrapolating the observed inhibitory effect over a range of concentrations to an infinitely high concentration of inhibitor, and estimating the transport component remaining at such a concentration. This component in transport would be expected to represent transport by simple diffusion, and this assumption was supported by the observation that for glycylsarcosine the uninhibitable component in transport was linearly proportional to substrate concentration; with l-glutamyl-l-glutamic acid the observations were too few to provide this demonstration. Estimates of apparent Kt and Vmax. for mediated transport of both peptides are given. Before correction for simple diffusion, linearizing plots were clearly biphasic for both peptides; after correction for simple diffusion, they became linear, providing no evidence for transport of either peptide by more than one mediated transport system, though not excluding the possibility of multiple systems. 3. Measurement of influx of [14C]Gly-Sar over a range of concentrations both alone and in the presence of a constant concentration of Glu-Glu showed that after correction for the non-mediated component in influx of Gly-Sar (simple diffusion), influx of this peptide conformed to Michaelis-Menten kinetics and the inhibitory effect of Glu-Glu on influx of Gly-Sar appeared to be competitive. The extent of inhibition corresponded well with that predicted from the Kt values of the two peptides. 4. Measurement of influx of [14C]Gly-Sar (1 mmol/l) in the presence of a range of concentrations of Glu-Glu, with extrapolation of the inhibitory effect of Glu-Glu to an infinitely high concentration of this peptide, showed that at such a concentration mediated influx of Gly-Sar was completely abolished, influx being reduced to the simple diffusion component in total influx of [14C]Gly-Sar. Measurement of influx of [14C]Glu-Glu (1 mmol/l) in the presence of a range of concentrations of Gly-Sar, with extrapolation of the inhibitory effect of Gly-Sar to an infinitely high concentration of this peptide, showed that at such a concentration mediated influx of Glu-Glu was completely abolished, influx being reduced to the simple diffusion component in total influx of [14C]Glu-Glu. 5. The results are compatible with the conclusion that Gly-Sar and Glu-Glu are taken up by the absorptive cells by a single mediated mechanism. They do not exclude the possibility that these peptides are taken up by multiple common mechanisms, but they do appear to exclude the possibility that at the substrate concentration used (1 mmol/l) there is appreciable uptake of one of the peptides by a system unavailable to the other.

Inhibition of absorption of d-xylose by phlorizin in the anesthetized rat

1965 ◽  
Vol 209 (1) ◽  
pp. 165-168 ◽  
Author(s):  
Antoun A. Salem ◽  
Arthur E. Cocco ◽  
Thomas R. Hendrix
Keyword(s):  
Transport Mechanism ◽  
Significant Inhibition ◽  
Sugar Concentration ◽  
High Concentration ◽  
Major Pathway ◽  
Anesthetized Rats

The effect of phlorizin on d-xylose absorption was studied in jejunal and ileal segments of anesthetized rats at different concentrations of the sugar. There was an inhibition of d-xylose absorption (79–92%) at sugar concentrations of 2.5 and 5.0 g/liter. A significant but less striking inhibition was demonstrated at a sugar concentration of 10 g/liter, but no significant inhibition could be demonstrated at a concentration of 50 g/liter. It is postulated that a specific "phlorizin-sensitive" transport mechanism is involved in d-xylose absorption and is the major pathway for absorption at low sugar concentrations. As the sugar concentration increases this mechanism becomes saturated and the amount of sugar transported through it becomes constant, while the fraction transported through a "phlorizin-insensitive" mechanism becomes greater. This would explain why at a relatively high concentration of 50 g/liter no significant inhibition could be demonstrated.

Cytomembrane Preservation in Tissue Dehydrated Only With Glutaraldehyde and Epon 812 Resin

1973 ◽  
Vol 31 ◽  
pp. 320-321
Author(s):  
Daniel C. Pease
Keyword(s):  
Diffraction Pattern ◽  
X Ray Diffraction ◽  
High Concentration ◽  
Unpublished Study ◽  
X Ray ◽  
Sectioned Material

A previous study demonstrated that tissue could be successfully infiltrated with 50% glutaraldehyde, and then subsequently polymerized with urea to create an embedment which retained cytomembrane lipids in sectioned material. As a result, the 180-190 Å periodicity characteristic of fresh, mammalian myelin was preserved in sections, as was a brilliant birefringence, and the capacity to bind OsO4 vapor in the hydrophobic bilayers. An associated (unpublished) study, carried out in co-operation with Drs. C.K. Akers and D.F. Parsons, demonstrated that the high concentration of glutaraldehyde (and urea) did not significantly alter the X-ray diffraction pattern of aldehyde-fixed, myelin. Thus, by itself, 50% glutaraldehyde has little effect upon cytomembrane systems and can be used with confidence for the first stages of dehydration.

Effects of Vincristine on Endothelial Microtubules in the Spinal Cord

1976 ◽  
Vol 34 ◽  
pp. 58-59
Author(s):  
John L. Beggs ◽  
John D. Waggener ◽  
Wanda Miller
Keyword(s):  
Spinal Cord ◽  
Biological Activity ◽  
Horseradish Peroxidase ◽  
Transport Mechanism ◽  
Vasogenic Edema ◽  
Vesicular Transport ◽  
Close Proximity

Microtubules (MT) are versatile organelles participating in a wide variety of biological activity. MT involvement in the movement and transport of cytoplasmic components has been well documented. In the course of our study on trauma-induced vasogenic edema in the spinal cord we have concluded that endothelial vesicles contribute to the edema process. Using horseradish peroxidase as a vascular tracer, labeled endothelial vesicles were present in all situations expected if a vesicular transport mechanism was in operation. Frequently,labeled vesicles coalesced to form channels that appeared to traverse the endothelium. The presence of MT in close proximity to labeled vesicles sugg ested that MT may play a role in vesicular activity.

Sign in / Sign up

Export Citation Format

Share Document