Expansion in the Width and Collective Dynamics of a Domain Wall

We show that collective dynamics of a curved domain wall in a (3+1)-dimensional relativistic scalar field model is represented by Nambu-Goto membrane and (2+1)-dimensional scalar fields defined on the worldsheet of the membrane. Our argument is based on a recently proposed by us version of the expansion in the width. Derivation of the expansion is significantly reformulated for the present purpose. Third and fourth order corrections to the domain wall solution are considered. We also derive an equation of motion for the core of the domain wall. Without the (2+1)-dimensional scalar fields this equation would be nonlocal.Comment: 26 pages, LaTeX, no figure

The role of subjective theories for leadership evaluation

The current article argues that taking subjective theories of both the rater and ratee into consideration contributes to a deeper understanding of leadership evaluations. In the present study, individuals' pre-existing implicit personality theory One of the most common and controversial concepts in organizational psychology is the concept of leadership. Diverse approaches have been developed and then discarded, leaving a lack of either a generally recognized Correspondence should be addressed t

Effect of cyclodextrin encapsulation on the photocyclization of diphenylamine: Cavity imposed restriction on the reaction rate

The kinetics of the photocyclization of diphenylamine (DPA) to carbazole (CAZL) has been studied fluorometrically in air-equilibrated aqueous solution as well as in constrained microheterogeneous media provided by [alpha]-, [beta]-, and [gamma]- cyclodextrins (CDs). It is observed that the fluorophore is embedded within the CD cavities without any alteration of the overall reaction quantum yield in the different environments. However, the rate of the photoreaction is modified remarkably within the CD environments. A restriction on the intramolecular rotation of the phenyl planes of DPA, imposed by the steric rigidity within the CD cavities, has been ascribed to be responsible for the suppression of the reaction rates within the CD environments. A semi-empirical (AM1) calculation gives the molecular dimension of the substrate and corroborates the proposition from a consideration of the cavity size of the different cyclodextrins.http://www.sciencedirect.com/science/article/B6TGR-44WJT2F-D/1/fbeee114a055a066bec9406d2538f43

Rationalizing Fabrication and Design Toward Highly Efficient and Stable Blue Light-Emitting Electrochemical Cells Based on NHC Copper(I) Complexes

International audienceRecently, the use of a new family of electroluminescent copper(I) complexes—i.e., the archetypal [Cu(IPr)(3‐Medpa)][PF6] complex; IPr: 1,3‐bis‐(2,6‐di‐iso‐propylphenyl)imidazole‐2‐ylidene; 3‐Medpa: 2,2′‐bis‐(3‐methylpyridyl)amine—has led to blue light‐emitting electrochemical cells (LECs) featuring luminances of 20 cd m−2, stabilities of 4 mJ, and efficiencies of 0.17 cd A−1. Herein, this study rationalizes how to enhance these figures‐of‐merit optimizing both device fabrication and design. On one hand, a comprehensive spectroscopic and electrochemical study reveals the degradation of this novel emitter in common solvents used for LEC fabrication, as well as the impact on the photoluminescence features of thin‐films. On the other hand, spectro‐electrochemical and electrochemical impedance spectroscopy assays suggest that the device performance is strongly limited by the irreversible formation of oxidized species that mainly act as carrier trappers and luminance quenchers. Based on all of the aforementioned, device optimization was realized using ionic additives and a hole transporter either as a host–guest or as a multilayered architecture approach to decouple hole/electron injection. The latter significantly enhances the LEC performance, reaching luminances of 160 cd m−2, stabilities of 32.7 mJ, and efficiencies of 1.2 cd A−1. Overall, this work highlights the need of optimizing both device fabrication and design toward highly efficient and stable LECs based on cationic copper(I) complexes