4,051 research outputs found
Review and evaluation of past solar cell development efforts
Bibliography on photovoltaic effect and solar cell developmen
Review and evaluation of past solar cell development efforts Semiannual report, Jun. 1 - Nov. 30, 1967
Historical review of scientific work on photovoltaic effects and on energy conversion devices using this effec
Development of an Accelerated Test Design for Predicting the Service Life of the Solar Array at Mead, Nebraska
Potential long-term degradation modes for the two types of modules in the Mead array were determined and judgments were made as to those environmental stresses and combinations of stresses which accelerate the degradation of the power output. Hierarchical trees representing the severity of effects of stresses (test conditions) on eleven individual degradation modes were constructed and were pruned of tests judged to be nonessential. Composites of those trees were developed so that there is now one pruned tree covering eight degradation modes, another covering two degradation modes, and a third covering one degradation mode. These three composite trees form the basis for selection of test conditions in the final test plan which is now being prepared
Progress in thin film GaAs solar cells
Solar cells using polycrystalline films of gallium arsenid
Hyperfine and Optical Barium Ion Qubits
State preparation, qubit rotation, and high fidelity readout are demonstrated
for two separate \baseven qubit types. First, an optical qubit on the narrow
6S to 5D transition at 1.76 m is implemented. Then,
leveraging the techniques developed there for readout, a ground state hyperfine
qubit using the magnetically insensitive transition at 8 GHz is accomplished
Measurement techniques and instruments suitable for life-prediction testing of photovoltaic arrays
Array failure modes, relevant materials property changes, and primary degradation mechanisms are discussed as a prerequisite to identifying suitable measurement techniques and instruments. Candidate techniques and instruments are identified on the basis of extensive reviews of published and unpublished information. These methods are organized in six measurement categories - chemical, electrical, optical, thermal, mechanical, and other physicals. Using specified evaluation criteria, the most promising techniques and instruments for use in life prediction tests of arrays were selected
Evaluation available encapsulation materials for low-cost long-life silicon photovoltaic arrays
Experimental evaluation of selected encapsulation designs and materials based on an earlier study which have potential for use in low cost, long-life photovoltaic arrays are reported. The performance of candidate materials and encapsulated cells were evaluated principally for three types of encapsulation designs based on their potentially low materials and processing costs: (1) polymeric coatings, transparent conformal coatings over the cell with a structural-support substrate; (2) polymeric film lamination, cells laminated between two films or sheets of polymeric materials; and (3) glass-covered systems, cells adhesively bonded to a glass cover (superstrate) with a polymeric pottant and a glass or other substrate material. Several other design types, including those utilizing polymer sheet and pottant materials, were also included in the investigation
Efficient numerical calculation of drift and diffusion coefficients in the diffusion approximation of kinetic equations
In this paper we study the diffusion approximation of a swarming model given by a system of interacting Langevin equations with nonlinear friction. The diffusion approximation requires the calculation of the drift and diffusion coefficients that are given as averages of solutions to appropriate Poisson equations. We present a new numerical method for computing these coefficients that is based on the calculation of the eigenvalues and eigenfunctions of a Schr¨odinger operator. These theoretical results are supported by numerical simulations showcasing the efficiency of the method
Social Interactions as a Source of Information about E-Cigarettes: A Study of U.S. Adult Smokers
The novelty of e-cigarettes and ambiguity about their effects may foster informal sharing of information, such as through social interactions. We aimed to describe smokers’ social interactions about e-cigarettes and their recommendations that others use e-cigarettes. Data were collected from 2149 adult smokers in North Carolina and California who participated in a study of the impact of pictorial cigarette pack warnings. In the previous month, almost half of participants (45%) reported talking to at least one person about e-cigarettes and nearly a third of participants (27%) recommended e-cigarettes to someone else. Smokers recommended e-cigarettes to cut back on smoking (57%), to quit smoking (48%), for health reasons (36%), and for fun (27%). In adjusted analyses, more frequent e-cigarette use, positive views about typical e-cigarette users, and attempting to quit smoking in the past month were associated with recommending e-cigarettes for health reasons (all p < 0.05). Social interactions appear to be a popular method of information-sharing about e-cigarettes among smokers. Health communication campaigns may help to fill in the gaps of smokers’ understanding of e-cigarettes and their long-term effects
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