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Light-emitting diode

A light-emitting diode (LED) is a semiconductor light source.[3] LEDs are used as indicator lamps in many devices and are increasingly used for other lighting. Introduced as a practical electronic component in 1962,[4] early LEDs emitted low-intensity red light, but modern versions are available across the visible, ultraviolet, and infrared wavelengths, with very high brightness. When a light-emitting diode is forward-biased (switched on), electrons are able to recombine with electron holes within the device, releasing energy in the form of photons. This effect is called electroluminescence and the color of the light (corresponding to the energy of the photon) is determined by the energy gap of the semiconductor. LEDs are often small in area (less than 1 mm2), and integrated optical components may be used to shape its radiation pattern.[5] LEDs present many advantages over incandescent light sources including lower energy consumption, longer lifetime, improved robustness, smaller size, and faster switching. LEDs powerful enough for room lighting are relatively expensive and require more precise current and heat management than compact fluorescent lamp sources of comparable output. Light-emitting diodes are used in applications as diverse as aviation lighting, automotive lighting, advertising, general lighting, and traffic signals. LEDs have allowed new text, video displays, live video, and sensors to be developed, while their high switching rates are also useful in advanced communications technology. Infrared LEDs are also used in the remote control units of many commercial products including televisions, DVD players, and other domestic appliances.

The BG-BL01 is a combination device, both solar battery charger and emergency LED Light. The solar power come courtesy of a HIT Solar panel, the same type of current generation panels that are found on homes. The BG-BL01 also comes equipped with a USB port, two AA Battery Charger slots and three LED lights.

ASUS lifted the veil over its long-awaited redesigned 9.2mm thin PadFone at the MWC. Sporting a 4.3-inch Super AMOLED qHD display, Snapdragon S4 with the new Adreno 225 GPU, and 8MP camera with LED flash and f/2.2 aperture, as well as 16-64GB of internal storage plus microSD slot, it has what we would expect from a modern high-end. Connectivity is taken care of 42Mbps HSPA+ radio, Wi-Fi, Bluetooth 4.0, HDMI and A-GPS, while a 1,520mAh battery unit is included as a juicer. The Padfone can get inserted into an optional tablet frame, whose 10.1 inch screen then gets powered by the phone itself, and can extend your battery life significantly. There is another dock, which allows you to add a detachable keyboard accessory, like on the Transformer Pad series. This one also comes with a stylus that except for doodling can be used to receive your phone calls as well, considering that the phone is inserted in the mothership.

The U49325 Sun Runner Stirling Engine is a solar-powered Stirling Engine which offers a dramatic demonstration of energy conversion.   This motor and its parabolic mirror can be attached to any conventional camera tripod. When properly aimed at the sun, the polished aluminum parabolic mirror focuses incoming solar energy on the heat cap of the engine, which is converted to rotary motion. Unit comes complete with motor, parabolic mirror, and wrenches. Standard camera tripod is not supplied. This engine is completely assembled and ready to run. Each unit is test run at the factory prior to shipping. Motor runs at 2,000 RPM and up. This engine can also run as a horizontal engine with an alcohol burner. Demonstrate this exciting method of harnessing the sun’s clean and renewable energy to your students.  Weight: 6.00 lbs Dimensions: Engine: 8.25 x 3 inches (L x W) Flywheel: 3.25 inchesParabolic Mirror: 18 inch diameterPlease note that this item is designed to demonstrate the operating principles of a Stirling engine for educational use and is not designed for power production.  It can potentially be coupled with a generator for producing very small amounts of electricity but is incapable of powering anything beyond a small light bulb or LED.

In the space of one hour, my entire digital life was destroyed. First my Google account was taken over, then deleted. Next my Twitter account was compromised, and used as a platform to broadcast racist and homophobic messages. And worst of all, my AppleID account was broken into, and my hackers used it to remotely erase all of the data on my iPhone, iPad, and MacBook.