Search results for "conduct"
showing 10 items of 4412 documents
Influence of Ge doping level on the EPR signal of Ge(1), Ge(2) and E'Ge defects in Ge-doped silica
2011
Abstract We present an experimental investigation on the Ge doping level dependence of the Electron Paramagnetic Resonance (EPR) signal spectral features of the Ge(1), Ge(2) and E'Ge defects induced in Ge doped silica. We have studied samples produced by sol–gel or PCVD techniques and doped with different amounts of Ge up to 20% by weight. The samples were gamma or beta ray irradiated and successively they were thermally treated to isolate the EPR signals of the different point defects. The data show that the EPR line shapes of the Ge(1) and the Ge(2) centers are progressively modified for doping level higher than 1%, whereas the line shape of the E'Ge defect appears independent from the do…
Solvothermal Synthesis of Molybdenum–Tungsten Oxides and Their Application for Photoelectrochemical Water Splitting
2018
Molybdenum and tungsten oxides are of interest as semiconductors for the production of clean and sustainable energy. Here we show that synergistic effects arising from a combination of noncrystalli...
Modeling of surface vs. bulk ionic conductivity in fixed charge membranes
2003
A two-region model for describing the conductivity of porous fixed charge membranes is proposed. In the surface region, the conductivity is due to the mobile positive ions (counterions) around the negative fixed charges. In the pore center region, the conductive properties resemble those of the external electrolyte solution because the fixed charges are assumed to be effectively neutralized by the counterions in the surface region. Activation energies and surface diffusion coefficients are estimated by assuming that the counterion jump from a fixed charge group is the rate limiting process for surface transport. The barrier energy for this jump is calculated using a simple electrostatic mod…
Electrostatic phenomena in ion exchange membranes
1971
Abstract Specific and transport properties of a cation and an anion exchange membrane in Na + and Cl - form respectively have been measured in water and dioxane water mixtures. A greater electrolyte absorption and a lesser specific conductivity and counterion transport number in solvents at higher dioxane content indicate strong electrostatic interactions between fixed groups in the membrane and counterions.
Analytical solutions of magnetohydrodynamical problems on a flow of conducting fluid in the entrance region of channels in a strong magnetic field šķ…
2014
Darbā iegūti analītiskie atrisinājumi magnetohidrodinamiskiem (MHD) uzdevumiem par elektrovadoša šķidruma plūsmu plakanā un cilindriskā kanālā stiprā magnētiskā laukā gadījumiem, kad šķidrums ietek kanālos caur galīga platuma spraugu vai caur galīga rādiusa atveri kanāla sānu malā. Pamatojoties uz iegūtajiem atrisinājumiem, veikta plūsmas ātruma lauka skaitliskā analīze. Iegūti uzdevumu asimptotiskie atrisinājumi lieliem Hartmana skaitļiem. Turklāt darbā pētīta pilna spiediena spēka šķidruma ieplūdes apgabalā atkarība no funkcijas veida, ar kuru ir uzdots ātruma robežnosacījums. Pētījums veikts analītiski, risinot divas hidrodinamiskas problēmas un divas MHD problēmas par viskoza šķidruma i…
Valores personales en el baloncesto de formación y su relación con el bienestar y la intención futura de práctica a través de la motivación
2020
RESUMEN Tomando como marco teórico la teoría de los valores humanos (Schwartz, 1992; Schwartz et al., 2012), y la teoría de la autodeterminación (Deci y Ryan, 1985, 2000), el objetivo del estudio consistió en poner a prueba un modelo, en una muestra de 115 jugadores jóvenes de baloncesto (Medad = 13.98, DT = 0.13), en el que se hipotetizó que los diferentes tipos de motivación (motivación autónoma, controlada y no motivación) actuarían como mediadores de la relación entre los valores informados por los jugadores (auto-trascendencia, conservación, auto-promoción y apertura al cambio) y los indicadores de bienestar (vitalidad subjetiva y afectos positivos), así como con la intención futura de…
La resistenza di interfaccia calcestruzzo poroso-terreni a grana fina per il consolidamento di pendii mediante trincee drenanti profonde
2022
Le trincee drenanti profonde rappresentano uno dei metodi più efficaci per la mitigazione del rischio da frana, in pendii con falda idrica. Esse sono realizzate mediante pannelli o pali secanti. Il riempimento è costituito di calcestruzzo poroso o materiale granulare. Se le trincee sono adeguatamente “innestate” nel terreno stabile e il materiale di riempimento ha sufficiente resistenza e rigidezza come il calcestruzzo poroso, si ha ulteriore in-cremento di resistenza a taglio per effetto shear keys, oltre a quello derivante dalla riduzione delle pressioni in-terstiziali. L’incremento di resistenza è dovuto sia alla resistenza all’interfaccia calcestruzzo–terreni sia a quella intrinseca del…
An Internet-delivered Cognitive-Behavioral Therapy (iCBT) for Prolonged Grief Disorder (PGD) in adults: A multiple-baseline single-case experimental …
2022
The death of a loved one has physical, psychological, and social consequences. Between 9.8 and 21.5 % of people who lose a loved one develop Prolonged Grief Disorder (PGD). Internet- and computer-based interventions (i.e., Internet-delivered Cognitive-Behavioral Therapy, iCBT) are cost-effective and scalable alternatives that make it possible to reach more people with PGD. The main goal of the present investigation was to examine the effect and feasibility (usability and satisfaction) of an iCBT (GROw program) for adults with PGD. A secondary objective was to detect adherence to the app (Emotional Monitor) used to measure daily grief symptoms. The study had a singlecase multiple-baseline AB…
EFECTOS A LARGO PLAZO DE UNA INTERVENCIÓN PSICOSOCIAL EN EL CONTEXTO FAMILIAR DE NIÑOS CON TDAH
2016
Abstract.The aim of this study was to analyze the long-term effects of an intervention that integrated three programs implemented with 27 children with ADHD combined subtype of 7 to 10 years old, their parents and their teachers. The intervention lasted 10 weeks and included behavior modification, cognitive behavioral techniques, social skills and academic accommodations. Effects on different variables of family functioning were assessed. The results show that significant improvements observed after treatment in virtually all the variables analyzed are not mostly maintained a year later. Complementary analyzes show, in line with the results obtained after treatment, lowers results in the su…
Intrinsic spin-orbit interaction in diffusive normal wire Josephson weak links: Supercurrent and density of states
2015
We study the effect of the intrinsic (Rashba or Dresselhaus) spin-orbit interaction in superconductor--nanowire--superconductor (SNS) weak links in the presence of a spin-splitting field that can result either from an intrinsic exchange field or the Zeeman effect of an applied field. We solve the full non-linear Usadel equations numerically and analyze the resulting supercurrent through the weak link and the behavior of the density of states in the center of the wire. We point out how the presence of the spin-orbit interaction gives rise to a long-range spin triplet supercurrent, which remains finite even in the limit of very large exchange fields. In particular, we show how rotating the fi…