Meyer-Neldel rule in the conductivity of phase separated manganites

Abstract Meyer-Neldel behaviour of the conductivity of phase separated La1−xCaxMnO3 manganite system in the low Ca-doping range has been investigated. Evolution of the isokinetic temperature of the conductivity, modified by Ca-doping, hydrostatic pressure and current bias has been determined. In addition, the evolution of the isokinetic temperature with ageing has also been studied. It is found that the Meyer-Neldel behaviour of the manganite system stems from multi-excitation entropy mechanism. The isokinetic temperatures estimated from pressure and doping effects coincide but differ from those determined using current and ageing controlled conductivity changes. It is concluded that in the presence of a detailed theoretical model of the excitations coupling in manganites, the investigations of the Meyer-Neldel effect may became a powerful tool for characterization and investigation of transport mechanisms in phase separated manganites.

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OCCURRENCE OF SUPERCONDUCTIVITY IN Ca-DOPED (Pb,Cu)Sr2PrCu2Oz

International Journal of Modern Physics B ◽

10.1142/s0217979205028578 ◽

2005 ◽

Vol 19 (01n03) ◽

pp. 361-367

Author(s):

H. K. LEE ◽

Y. H. KIM ◽

D. H. HA

Keyword(s):

Magnetic Properties ◽

Electrical Resistivity ◽

Structural Changes ◽

Hole Doping ◽

Ca Doping ◽

Bulk Ceramic ◽

Electrical And Magnetic Properties ◽

Ceramic Samples ◽

Doping Effects ◽

Occurrence Of Superconductivity

We have investigated the Ca -doping effects on the structural, electrical and magnetic properties of ( Pb 0.5 Cu 0.5) Sr 2( Pr 1-x Ca x Cu 2 O z( x =0-0.5) bulk ceramic samples. The electrical resistivity, thermoelectric power and magnetic susceptibility measurements reveal that the Ca doping introduces holes into the system and thereby superconductivity with onset T c, of about 36 K is induced for a phase with x =0.5. These results are discussed in conjunction with the roles of hole doping, structural changes and Pr - O hybridization in CuO 2 layers.

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Ca-doping effects on N-type ferrimagnetism of NdVO3

Solid State Communications ◽

10.1016/j.ssc.2004.12.044 ◽

2005 ◽

Vol 133 (9) ◽

pp. 559-564 ◽

Cited By ~ 13

Author(s):

Y. Kimishima ◽

M. Uehara ◽

T. Saitoh

Keyword(s):

Ca Doping ◽

Doping Effects

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Blood Volume Modeling and Refilling Rate Estimation in Hemodialysis by Continuous Hemoglobin Monitoring

The International Journal of Artificial Organs ◽

10.1177/039139889501800906 ◽

1995 ◽

Vol 18 (9) ◽

pp. 509-512 ◽

Cited By ~ 3

Author(s):

G. Arrigo ◽

R. Bucci ◽

G. Colasanti ◽

A. Rustici ◽

M. Sivo ◽

...

Keyword(s):

Experimental Data ◽

Theoretical Model ◽

Hydrostatic Pressure ◽

Blood Volume ◽

Dynamic Modeling ◽

Protein Concentration ◽

Time Course ◽

Data Series ◽

Plasma Protein Concentration ◽

Volume Modeling

Eleven bicarbonate hemodialyses (HD) of 6 patients under constant ultrafiltration were continuously monitored with an optical Hb-meter, considered to be a marker of blood volume (BV) changes. A theoretical model was fed experimental data for prediction of blood volume and estimation of vascular parameters, and a time course of rate of refilling was extrapolated. The adequacy of the model was very good for the time course of BV prediction (r2=0.85-0.95, n=11) and for plasma protein concentration (r2=0.83-0.86, n=2). Parameters estimated included (mean-DS): filtration coefficient (Cf)=0.22 (0.16) dl/min∗mmHg, transcapillary hydrostatic pressure (DP)=17.80 (3.44) mmHg and protein concentration of the refilling fluid (Cref)=0.45 (0.30) g/dl. In conclusion our study has shown that the model chosen fits the observed BV profile well in all cases, thus the Hb data series can be used for BV dynamic modeling and for estimation of vascular parameters.

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Ca Doping Effects in YBa2Cu4O8 Prepared by the Citrate Pyrolysis Method

Advances in Superconductivity IV ◽

10.1007/978-4-431-68195-3_51 ◽

1992 ◽

pp. 245-248

Author(s):

Kuniyuki Koyama ◽

Alain Junod ◽

Thomas Graf ◽

Gilles Triscone ◽

Jean Muller

Keyword(s):

Ca Doping ◽

Pyrolysis Method ◽

Doping Effects

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Physical Properties of Isolated Perfused Renal Tubular Basement Membranes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065997 ◽

1971 ◽

Vol 29 ◽

pp. 390-391

Author(s):

Jared Grantham ◽

Larry Welling

Keyword(s):

Basement Membrane ◽

Basement Membranes ◽

Transport Mechanisms ◽

Permeability Characteristics ◽

Peritubular Capillaries ◽

Strategic Location ◽

Tubular Lumen ◽

Glomerular Filtrate ◽

Urine Formation ◽

Renal Tubular

In the course of urine formation in mammalian kidneys over 90% of the glomerular filtrate moves from the tubular lumen into the peritubular capillaries by both active and passive transport mechanisms. In all of the morphologically distinct segments of the renal tubule, e.g. proximal tubule, loop of Henle and distal nephron, the tubular absorbate passes through a basement membrane which rests against the basilar surface of the epithelial cells. The basement membrane is in a strategic location to affect the geometry of the tubules and to influence the movement of tubular absorbate into the renal interstitium. In the present studies we have determined directly some of the mechanical and permeability characteristics of tubular basement membranes.

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Doping effects on the geometric and electronic structure of tin clusters

Physical Chemistry Chemical Physics ◽

10.1039/c9cp05124d ◽

2019 ◽

Vol 21 (44) ◽

pp. 24478-24488 ◽

Cited By ~ 1

Author(s):

Martin Gleditzsch ◽

Marc Jäger ◽

Lukáš F. Pašteka ◽

Armin Shayeghi ◽

Rolf Schäfer

Keyword(s):

Density Functional Theory ◽

Electronic Structure ◽

Density Functional ◽

Beam Deflection ◽

Functional Theory ◽

Doping Effects ◽

Depth Analysis ◽

Trajectory Simulations

In depth analysis of doping effects on the geometric and electronic structure of tin clusters via electric beam deflection, numerical trajectory simulations and density functional theory.

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A theoretical model for understanding dentists' behavior in treating patients with AIDS

Journal of Dental Education ◽

10.1002/j.0022-0337.1991.55.11.tb02589.x ◽

1991 ◽

Vol 55 (11) ◽

pp. 708-716 ◽

Cited By ~ 1

Author(s):

MS Chen

Keyword(s):

Theoretical Model

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Alveolobronchiolar transport mechanisms

Archives of Internal Medicine ◽

10.1001/archinte.131.1.109 ◽

1973 ◽

Vol 131 (1) ◽

pp. 109-114 ◽

Cited By ~ 19

Author(s):

G. M. Green

Keyword(s):

Transport Mechanisms

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A Model for Analyzing Suicide Prevention

Crisis ◽

10.1027//0227-5910.21.2.80 ◽

2000 ◽

Vol 21 (2) ◽

pp. 80-89 ◽

Cited By ~ 3

Author(s):

Maila Upanne

Keyword(s):

Risk Factors ◽

Theoretical Model ◽

Protective Factors ◽

Suicide Prevention ◽

Suicide Risk ◽

Practical Work ◽

Individual Risk ◽

Self Assessment ◽

Prevention Project ◽

Individual Risk Factors

This study monitored the evolution of psychologists' (n = 31) conceptions of suicide prevention over the 9-year course of the National Suicide Prevention Project in Finland and assessed the feasibility of the theoretical model for analyzing suicide prevention developed in earlier studies [ Upanne, 1999a , b ]. The study was formulated as a retrospective self-assessment where participants compared their earlier descriptions of suicide prevention with their current views. The changes in conceptions were analyzed and interpreted using both the model and the explanations given by the subjects themselves. The analysis proved the model to be a useful framework for revealing the essential features of prevention. The results showed that the freely-formulated ideas on prevention were more comprehensive than those evolved in practical work. Compared to the earlier findings, the conceptions among the group had shifted toward emphasizing a curative approach and the significance of individual risk factors. In particular, greater priority was focused on the acute suicide risk phase as a preventive target. Nonetheless, the overall structure of prevention ideology remained comprehensive and multifactorial, stressing multistage influencing. Promotive aims (protective factors) also remained part of the prevention paradigm. Practical working experiences enhanced the psychologists' sense of the difficulties of suicide prevention as well as their criticism and feeling of powerlessness.

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