Search results for "Theory"
showing 10 items of 24627 documents
Perfectionism and performance-related psychobiosocial states: The mediating role of competition appraisals.
2022
Using the multi-states (MuSt) theory as a framework, the present study focused on the individual (personality) antecedents of psychobiosocial states. Psychobiosocial states comprise emotional subjective experiences and their correlates (cognitive, motivational, volitional, bodily, motor-behavioural, operational, and communicative), that can be functional for performance (helpful) or dysfunctional (harmful). Specifically, we examined the relationships between two perfectionism dimensions (perfectionistic strivings and concerns) and functional and dysfunctional psychobiosocial states. The hypothesised mediational role of competitive appraisals was also tested. Participants (N = 271, 138 femal…
Copper-hydride nanoclusters with enhanced stability by N-heterocyclic carbenes
2021
AbstractCopper-hydrides have been intensively studied for a long time due to their utilization in a variety of technologically important chemical transformations. Nevertheless, poor stability of the species severely hinders its isolation, storage and operation, which is worse for nano-sized ones. We report here an unprecedented strategy to access to ultrastable copper-hydride nanoclusters (NCs), namely, using bidentate N-heterocyclic carbenes as stabilizing ligands in addition to thiolates. In this work, a simple synthetic protocol was developed to synthesize the first large copper-hydride nanoclusters (NCs) stabilized by N-heterocyclic carbenes (NHCs). The NC, with the formula of Cu31(RS)2…
Thiol-Stabilized Atomically Precise, Superatomic Silver Nanoparticles for Catalyzing Cycloisomerization of Alkynyl Amines
2018
Abstract Both the electronic and surface structures of metal nanomaterials play critical roles in determining their chemical properties. However, the non-molecular nature of conventional nanoparticles makes it extremely challenging to understand the molecular mechanism behind many of their unique electronic and surface properties. In this work, we report the synthesis, molecular and electronic structures of an atomically precise nanoparticle, [Ag206L72]q (L = thiolate, halide; q = charge). With a four-shell Ag7@Ag32@Ag77@Ag90 Ino-decahedral structure having a nearly perfect D5h symmetry, the metal core of the nanoparticle is co-stabilized by 68 thiolate and 4 halide ligands. Both electroche…
Electronic shell structures in bare and protected metal nanoclusters
2016
This short review discusses the concept of the electronic shell structure in the context of metal nanoclusters. Electronic shell structure is a natural consequence of quantization of fermionic states in a quantum confinement, where the symmetry of the confining potential creates energetically close-lying sets of states that reflect the symmetry of the potential. It was introduced in cluster physics in early 1980s and initially influenced greatly by the related model of nuclear shell structure from 1950’s. Three application areas are discussed consisting of free gas phase clusters, clusters supported by insulating oxides or oxide thin films, and clusters that are synthesized by wet chemistry…
Rotational properties of nuclei around 254 No investigated using a spectroscopic-quality Skyrme energy density functional
2014
Abstract. Background: Nuclei in the Z≈100 mass region represent the heaviest systems where detailed spectroscopic information is experimentally available. Although microscopic-macroscopic and self-consistent models have achieved great success in describing the data in this mass region, a fully satisfying precise theoretical description is still missing. Purpose: By using fine-tuned parametrizations of the energy density functionals, the present work aims at an improved description of the single-particle properties and rotational bands in the nobelium region. Such locally optimized parametrizations may have better properties when extrapolating towards the superheavy region. Methods: Skyrme H…
Supernova-neutrino induced reactions on molybdenum via neutral-currents
2012
In this thesis which consists of an introductory part and six publications the neutralcurrent neutrino-nucleus scatterings o the stable molybdenum nuclei are studied using microscopic nuclear models. The main focus is on supernova neutrinos and the nuclear responses to them for the aforementioned nuclei are computed by folding the computed cross sections with realistic neutrino-energy spectra. In this work both the coherent and incoherent contributions to the cross sections are considered. The contributions from the prominent multipole channels to the incoherent cross sections are also discussed in great detail.
Shell-model study on event rates of lightest supersymmetric particles scattering off 83Kr and 125Te
2016
We investigate the elastic and inelastic scattering of lightest supersymmetric particle (LSP) dark matter off two possible target nuclei, 83Kr and 125Te. For the nuclear-structure calculations, we employ the nuclear shell model using recently generated realistic interactions. We have condensed the nuclear-physics contribution to a set of nuclear-structure factors that are independent of the adopted supersymmetric (SUSY) model. Total event rates are then easily calculated by combining the nuclear-structure factors with SUSY parameters of choice. In particular, 125Te shows promise as a detector material with both the elastic and inelastic channels yielding an appreciable nuclear response. pee…
Global analysis of the pMSSM in light of the Fermi GeV excess: prospects for the LHC Run-II and astroparticle experiments
2016
We present a new global fit of the 19-dimensional phenomenological Minimal Supersymmetric Standard Model (pMSSM-19) that comply with all the latest experimental results from dark matter indirect, direct and accelerator dark matter searches. We show that the model provides a satisfactory explanation of the excess of gamma-rays from the Galactic centre observed by the Fermi~Large Area Telescope, assuming that it is produced by the annihilation of neutralinos in the Milky Way halo. We identify two regions that pass all the constraints: the first corresponds to neutralinos with a mass ~80-100 GeV annihilating into WW with a branching ratio of 95% ; the second to heavier neutralinos, with mass ~…
About the reinterpretation of the Ghosh model as a price model
2001
The Ghosh model assumes that, in an input-output framework, each commodity is sold to each sector in fixed proportions. This model is strongly criticized because it seems implausible in the traditional input-output field. To answer to these critics, Dietzenbacher stresses that it can be reinterpreted as a price model: the Leontief price model is equivalent to the Ghosh model when this one is interpreted as a price model. This paper shows that the interpretation of the Ghosh model as a price model cannot be accepted because Dietzenbacher makes a strong assumption, dichotomy, while the Ghosh model does not determine prices...
Self-consistent calculation of the flux-flow conductivity in diffusive superconductors
2017
In the framework of Keldysh-Usadel kinetic theory, we study the temperature dependence of flux-flow conductivity (FFC) in diffusive superconductors. By using self-consistent vortex solutions we find the exact values of dimensionless parameters that determine the diffusion-controlled FFC both in the limit of the low temperatures and close to the critical one. Taking into account the electron-phonon scattering, we study the transition between flux-flow regimes controlled by either the diffusion or the inelastic relaxation of nonequilibrium quasiparticles. We demonstrate that the inelastic electron-phonon relaxation leads to the strong suppression of FFC compared to the previous estimates, mak…