595 research outputs found
Plasmonic backscattering enhanced inverted photovoltaics
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98669/1/ApplPhysLett_99_113306.pd
A first-principles study of the vibrational properties of crystalline tetracene under pressure
Mode substitution induced by electric mobility hubs: Results from Amsterdam
\ua9 2024 The Author(s)Electric mobility hubs (eHUBS) are locations where multiple shared electric modes including electric cars and e-bikes are available. To assess their potential to reduce private car use, it is important to investigate to what extent people would switch to eHUBS modes after their introduction. Moreover, people may adapt their behaviour differently depending on their current travel mode. This study is based on stated preference data collected in Amsterdam. We analysed the data using mixed logit models. We found that users of different modes not only have varied general preferences for different shared modes but also have different sensitivity for attributes such as travel time and cost. Public transport users are more likely to switch to eHUBS modes than car users. People who bike and walk have strong inertia, but the percentage choosing eHUBS modes doubles when the trip distance is longer (5 or 10 km)
Monte-Carlo simulations of the recombination dynamics in porous silicon
A simple lattice model describing the recombination dynamics in visible light
emitting porous Silicon is presented. In the model, each occupied lattice site
represents a Si crystal of nanometer size. The disordered structure of porous
Silicon is modeled by modified random percolation networks in two and three
dimensions. Both correlated (excitons) and uncorrelated electron-hole pairs
have been studied. Radiative and non-radiative processes as well as hopping
between nearest neighbor occupied sites are taken into account. By means of
extensive Monte-Carlo simulations, we show that the recombination dynamics in
porous Silicon is due to a dispersive diffusion of excitons in a disordered
arrangement of interconnected Si quantum dots. The simulated luminescence decay
for the excitons shows a stretched exponential lineshape while for uncorrelated
electron-hole pairs a power law decay is suggested. Our results successfully
account for the recombination dynamics recently observed in the experiments.
The present model is a prototype for a larger class of models describing
diffusion of particles in a complex disordered system.Comment: 33 pages, RevTeX, 19 figures available on request to
[email protected]
Evaluation of in-vivo and in-vitro microbiological methods for testing the efficacy of parenteral antibiotics: A Review
Antibiotics are available as innovators and generics. An innovator or branded drug is a medicine that is discovered, developed and marketed by a pharmaceutical company which also holds the patent for that drug. Generics only become available after the patent on the innovator expires. Generic drugs are required to have the same active ingredient, strength, dosage form, and route of administration as the innovator product. Generics should be bioequivalent to the innovator and when used, should have the same efficacy and safety profile. This is crucial for parenteral antibiotics because according to the World Health Organization and U.S. Food and Drug Administration criteria, parenteral generic products do not need to provide evidence for in-vivo bioavailability or bioequivalence before they can be marketed. Published evidence shows that there is a disparity in the efficacy of different generic antibiotic products. In-vitro microbiological methods of efficacy testing have been recognized as a standardized and cost-effective approach to clarify doubts regarding the efficacy of generic parenteral antibiotics. However, in-vitro methods used alone, might not be a good measurement of antibiotic efficacy as several studies have shown disparities between in-vitro and in-vivo efficacy of parenteral antibiotics.</p
Electrochemical integration of graphene with light absorbing copper-based thin films
We present an electrochemical route for the integration of graphene with
light sensitive copper-based alloys used in optoelectronic applications.
Graphene grown using chemical vapor deposition (CVD) transferred to glass is
found to be a robust substrate on which photoconductive Cu_{x}S films of 1-2 um
thickness can be deposited. The effect of growth parameters on the morphology
and photoconductivity of Cu_{x}S films is presented. Current-voltage
characterization and photoconductivity decay experiments are performed with
graphene as one contact and silver epoxy as the other
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