1,550 research outputs found
Solar cell research, phase 2 Semiannual report
Radiation effects on properties of lithium solar cell
A toolkit of mechanism and context independent widgets
Most human-computer interfaces are designed to run on a static platform (e.g. a workstation with a monitor) in a static environment (e.g. an office). However, with mobile devices becoming ubiquitous and capable of running applications similar to those found on static devices, it is no longer valid to design static interfaces. This paper describes a user-interface architecture which allows interactors to be flexible about the way they are presented. This flexibility is defined by the different input and output mechanisms used. An interactor may use different mechanisms depending upon their suitability in the current context, user preference and the resources available for presentation using that mechanism
Deterministic nano-assembly of a coupled quantum emitter - photonic crystal cavity system
The interaction of a single quantum emitter with its environment is a central
theme in quantum optics. When placed in highly confined optical fields, such as
those created in optical cavities or plasmonic structures, the optical
properties of the emitter can change drastically. In particular, photonic
crystal (PC) cavities show high quality factors combined with an extremely
small mode volume. Efficiently coupling a single quantum emitter to a PC cavity
is challenging because of the required positioning accuracy. Here, we
demonstrate deterministic coupling of single Nitrogen-Vacancy (NV) centers to
high-quality gallium phosphide PC cavities, by deterministically positioning
their 50 nm-sized host nanocrystals into the cavity mode maximum with
few-nanometer accuracy. The coupling results in a 25-fold enhancement of NV
center emission at the cavity wavelength. With this technique, the NV center
photoluminescence spectrum can be reshaped allowing for efficient generation of
coherent photons, providing new opportunities for quantum science.Comment: 13 pages, 4 figure
Robust concurrent remote entanglement between two superconducting qubits
Entangling two remote quantum systems which never interact directly is an
essential primitive in quantum information science and forms the basis for the
modular architecture of quantum computing. When protocols to generate these
remote entangled pairs rely on using traveling single photon states as carriers
of quantum information, they can be made robust to photon losses, unlike
schemes that rely on continuous variable states. However, efficiently detecting
single photons is challenging in the domain of superconducting quantum circuits
because of the low energy of microwave quanta. Here, we report the realization
of a robust form of concurrent remote entanglement based on a novel microwave
photon detector implemented in the superconducting circuit quantum
electrodynamics (cQED) platform of quantum information. Remote entangled pairs
with a fidelity of are generated at Hz. Our experiment
opens the way for the implementation of the modular architecture of quantum
computation with superconducting qubits.Comment: Main paper: 7 pages, 4 figures; Appendices: 14 pages, 9 figure
A Topside Equatorial Ionospheric Density and Composition Climatology During and After Extreme Solar Minimum
During the recent solar minimum, solar activity reached the lowest levels observed during the space age. This extremely low solar activity has accompanied a number of unexpected observations in the Earth's ionosphere and thermosphere when compared to previous solar minima. Among these are the fact that the ionosphere is significantly contracted beyond expectations based on empirical models. Climatological altitude profiles of ion density and composition measurements near the magnetic dip equator are constructed from the C/NOFS satellite to characterize the shape of the top side ionosphere during the recent solar minimum and into the new solar cycle. The variation of the profiles with respect to local time, season, and solar activity are compared to the IRI-2007 model. Building on initial results reported by Heelis et al. [2009], here we describe the extent of the contracted ionosphere, which is found to persist throughout 2009. The shape of the ionosphere during 2010 is found to be consistent with observations from previous solar minima
Performance of the IRI-2007 Model for Topside Ion Density and Composition Profiles During the 23/24 Solar Minimum
The recent solar minimum between cycles 23 and 24 was unusually extended and deep, resulting in an ionosphere that is significantly different from that expected based on previous solar minima. The ion density and composition estimates from the Communication/Navigation Outage Forecast System (C/NOFS) satellite are used to evaluate the performance of the IRI-2007 model between 400 and 850 kIn altitude in equatorial regions. The current model is shown to typically overestimate the expected topside density of 0+ and underestimate the density of H+ during 2008 and 2009. The overestimation of ion density by IRI-2007 is found to vary with local time and longitude
In Situ NMR Parameter Monitoring Systems and Methods for Measuring PH and Temperature
Devices and methods are provided for measuring temperatures and pHs of a sample in situ using NMR spectroscopy, and for sealing one or more ends of a capillary tube after a reference material has been added to the capillary tube, which is used in an in situ NMR temperature measurement device. A method for measuring a pH of a sample in situ using NMR spectroscopy includes providing an in situ NMR pH measurement device. This device includes a sample housing member configured to house a target sample, at least one pH sensor configured to exhibit an NMR spectral change due to a change in pH value of the target sample, and a pH sensor containment member configured to house the at least one pH sensor. The target sample is added to the sample housing member. NMR spectra are obtained to then determine the pH of the target sample
Transport of Cytoplasmically Synthesized Proteins into the Mitochondria in a Cell Free System from Neurospora crassa
Synthesis and transport of mitochondrial proteins were followed in a cell-free homogenate of Neurospora crassa in which mitochondrial translation was inhibited. Proteins synthesized on cytoplasmic ribosomes are transferred into the mitochondrial fraction. The relative amounts of proteins which are transferred in vitro are comparable to those transferred in whole cells.
Cycloheximide and puromycin inhibit the synthesis of mitochondrial proteins but not their transfer into mitochondria.
The transfer of immunoprecipitable mitochondrial proteins was demonstrated for matrix proteins, carboxyatractyloside-binding protein and cytochrome c.
Import of proteins into mitochondria exhibits a degree of specificity. The transport mechanism differentiates between newly synthesized proteins and preexistent mitochondrial proteins, at least in the case of matrix proteins.
In the cell-free homogenate membrane-bound ribosomes are more active in the synthesis of mitochondrial proteins than are free ribosomes. The finished translation products appear to be released from the membrane-bound ribosomes into the cytosol rather than into the membrane vesicles.
The results suggest that the transport of cytoplasmically synthesized mitochondrial proteins is essentially independent of cytoplasmic translation; that cytoplasmically synthesized mitochondrial proteins exist in an extramitochondrial pool prior to import; that the site of this pool is the cytosol for at least some of the mitochondrial proteins; and that the precursors in the extramitochondrial pool differ in structure or conformation from the functional proteins in the mitochondria
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