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How can I Find the Average Color of a Photograph? Many popular image-editing tools allow you to determine the average color of a small section of an image, but we couldn't find any that could calculate the average color of an entire photograph. Enter, the Average Color Tool. Possible Uses Lithium−Air Battery: Promise and Challenges - The Journal of Physical Chemistry Letters IBM Research - Almaden, 650 Harry Road, San José, California 95120 J. Phys. Chem. Lett., 2010, 1 (14), pp 2193–2203

Videos Account Options Videos Enjoy your holiday favorites on the big screen. 'Tis the season for Chromecast. Lithium-Air Batteries: An Overview Yuan Zhong December 3, 2011 Submitted as coursework for PH240, Stanford University, Fall 2011 Introduction The technological revolution over the past centuries consumes vast amount of energy and results in significant carbon footprint. A dominate proportion of overall energy demand is attributed to transportation sector which leads to various environmental problems, such as urban air pollution. Approximately 80% of national CO emission is accounted for transportations. [1] With foreseeable shortage of fuels and emphasis on being green, electrification of road transportation is a potential solution to both energy conservation and environmental protection.

Quintura Quintura - visual search engine Quintura - visual search engine for hotels ⚫ London hotels Lithium–air battery The major appeal of the Li-air battery is the extremely high energy density, a measure of the amount of energy a battery can store for a given mass. A lithium-air battery has an energy density (per kilo) comparable to traditional gasoline per kilo. Li-air batteries gain this advantage in energy density since they use oxygen from the air instead of storing an oxidizer internally. The technology requires significant research in a variety of fields before a viable commercial implementation is expected.[1] Four approaches are being pursued; aprotic,[2][3] aqueous,[4] solid state,[5] and mixed aqueous/aprotic.[6] Lithium batteries have received considerable attention over the past 40 years.

MechE - Yang Shao-Horn Gail E. Kendall Professor of Mechanical EngineeringElectrochemical Energy Laboratory, 31-056 Room 3-334Massachusetts Institute of Technology77 Massachusetts AvenueCambridge MA 02139-4307Phone: 617-253-2259 Fax: 617-258-7018 Email: shaohorn@mit.eduWeb: Theoretical Energy Density of Li–Air Batteries + Author Affiliations Abstract A model for predication of the gravimetric and volumetric energy densities of Li-air batteries using aqueous electrolytes is developed. The theoretical gravimetric/volumetric capacities and energy densities are calculated based on the minimum weight of the electrolyte and volume of air electrode needed for completion of the electrochemical reaction with Li metal as an anode electrode. It was determined that both theoretical gravimetric/volumetric capacities and energy densities are dependent on the porosity of the air electrode. For instance, at a porosity of 70%, the maximum theoretical cell capacities are and in basic electrolyte, and and in acidic electrolyte.

Iron-air batteries may prove a cheap, eco-friendly solution for energy storage Revamping a concept that was first explored forty years ago, researchers at the University of Southern California (USC) are putting the final touches on a patent-pending design for cheap, rechargeable, high energy density iron-air batteries. Because of their unique features, the batteries look particularly well-suited to the kind of large-scale energy storage that could accelerate the adoption of renewable energy sources. The quest for a cheap, environmentally friendly rechargeable battery stretches back for decades. For one, lithium-ion batteries were first proposed in the seventies, and only recent advances in materials technology have made this technology into one of the most common, high-performing solutions for today's portable electronics. Now, a team of USC researchers may have found the key to resuscitating yet another design first proposed around the same time – the iron-air battery.

A New Class of Electrocatalysts for Hydrogen Production from Water Electrolysis: Metal Monolayers Supported on Low-Cost Transition Metal Carbides - Journal of the American Chemical Society Department of Chemical Engineering, University of Delaware, Newark, Delaware 19716, United States J. Am. Chem. Abundance of the chemical elements Estimated proportions of matter, dark matter and dark energy in the universe. Only the fraction of the mass and energy in the universe labeled "atoms" is composed of chemical elements. For example, the mass-fraction abundance of oxygen in water is about 89%, because that is the fraction of water's mass which is oxygen. However, the mole-fraction abundance of oxygen in water is only 33% because only 1 atom of 3 in water is an oxygen atom. In the universe as a whole, and in the atmospheres of gas-giant planets such as Jupiter, the mass-fraction abundances of hydrogen and helium are about 74% and 23–25% respectively, while the (atomic) mole-fractions of these elements are closer to 92% and 8%.

Advanced materials for sodium-beta alumina batteries: Status, challenges and perspectives Journal of Power Sources 195 (2010) 2431–2442 Contents lists available at ScienceDirect Journal of Power Sources journal homepage:

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