190 research outputs found
Strain-induced energy band gap opening in two-dimensional bilayered silicon film
This work presents a theoretical study of the structural and electronic
properties of bilayered silicon films under in-plane biaxial strain/stress
using density functional theory. Atomic structures of the two-dimensional
silicon films are optimized by using both the local-density approximation and
generalized gradient approximation. In the absence of strain/stress, five
buckled hexagonal honeycomb structures of the bilayered silicon film have been
obtained as local energy minima and their structural stability has been
verified. These structures present a Dirac-cone shaped energy band diagram with
zero energy band gaps. Applying tensile biaxial strain leads to a reduction of
the buckling height. Atomically flat structures with zero bucking height have
been observed when the AA-stacking structures are under a critical biaxial
strain. Increase of the strain between 10.7% ~ 15.4% results in a band-gap
opening with a maximum energy band gap opening of ~168.0 meV obtained when
14.3% strain is applied. Energy band diagram, electron transmission efficiency,
and the charge transport property are calculated.Comment: 18 pages, 5 figures, 1 tabl
MODELING ANALYSIS OF THE IMPACT OF RURAL TOURISM ON ALLEVIATING THE RISK OF ALZHEIMERâS DISEASE
MODELING ANALYSIS OF THE IMPACT OF RURAL TOURISM ON ALLEVIATING THE RISK OF ALZHEIMERâS DISEASE
THE INFLUENCE OF THE SPATIOTEMPORAL EVOLUTION AND MECHANISM OF RURAL TOURISM INDUSTRY AGGLOMERATION ON TOURISTSâ CONSUMPTION MENTALITY FROM THE PERSPECTIVE OF SOCIAL PSYCHOLOGY
THE INFLUENCE OF THE SPATIOTEMPORAL EVOLUTION AND MECHANISM OF RURAL TOURISM INDUSTRY AGGLOMERATION ON TOURISTSâ CONSUMPTION MENTALITY FROM THE PERSPECTIVE OF SOCIAL PSYCHOLOGY
The Influences of Coal Mining Collapse on the Saturation Conductivity of Soil in Maowusu Sandy Land
Properties of Two-Dimensional Silicon grown on Graphene Substrate
The structure and electrical properties of a two-dimensional (2D) sheet of
silicon on a graphene substrate are studied using first-principles
calculations. A new corrugated rectangular structure of silicon is proposed to
be the most energetically favorable structure. The shifting of the Fermi energy
level indicates self-doping. Calculation of electron density shows a weak
coupling between the silicon layer and graphene substrate. The 2D silicon sheet
turns to be metallic and has a much higher value of transmission efficiency
(TE) than the underlying graphene substrate.Comment: 5 Pages, 7 figure
Ganoderma lucidum Protects Dopaminergic Neuron Degeneration through Inhibition of Microglial Activation
Abundant evidence has suggested that neuroinflammation participates in the pathogenesis of Parkinson's disease (PD). The emerging evidence has supported that microglia may play key roles in the progressive neurodegeneration in PD and might be a promising therapeutic target. Ganoderma lucidum (GL), a traditional Chinese medicinal herb, has been shown potential neuroprotective effects in our clinical trials that make us to speculate that it might possess potent anti-inflammatory and immunomodulating properties. To test this hypothesis, we investigated the potential neuroprotective effect of GL and possible underlying mechanism of action through protecting microglial activation using co-cultures of dopaminergic neurons and microglia. The microglia is activated by LPS and MPP+-treated MES 23.5 cell membranes. Meanwhile, GL extracts significantly prevent the production of microglia-derived proinflammatory and cytotoxic factors [nitric oxide, tumor necrosis factor-α (TNF-α), interlukin 1ÎČ (IL-1ÎČ)] in a dose-dependent manner and down-regulate the TNF-α and IL-1ÎČ expressions on mRNA level as well. In conclusion, our results support that GL may be a promising agent for the treatment of PD through anti-inflammation
Numerical calculation of oil film for ship stern bearing based on matrix method
Radial sliding bearings are widely used in ship shafting, its characteristics of lubricating oil film have important influence on the normal operation of the whole shaft system. In this work, the difference equations which is used to calculate the radial sliding bearing oil film features is transformed into matrix equations, the solving process be converted into solving matrix equation, combined with the powerful matrix calculation function of MATLAB, the solution process is simplified. It is not necessary to set the error precision and relaxation factor, so as to avoid the problem that the calculation result is not stable or even not convergent in the process of Successive Over Relaxation(SOR) method, and the calculation precision and stability are improved. The numerical results of matrix calculation method is compared with the result of SOR method, verified the correctness and feasibility of the matrix calculation method. Because the calculation is relatively stable, the matrix calculation method is more suitable for the calculation core of the relative computing software
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