ARTICLES PUBLISHED ONLINE: 18 MAY 2015 | DOI: 10.1038/NNANO.2015.89 Black silicon solar cells with interdigitated back-contacts achieve 22.1% efficiency Hele Savin1*, Päivikki Repo1, Guillaume von Gastrow1, Pablo Ortega2, Eric Calle2, Moises Garín2 and Ramon Alcubilla2 The nanostructuring of silicon surfaces—known as black silicon—is a promising approach to eliminate front-surface reflection in photovoltaic devices without the need for a conventional antireflection coating. This might lead
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Colon cancer develops in the large intestine (colon), the lower part of your digestive system. Rectal cancer develops in the rectum, which makes up the last several inches of your intestinal tract. Together, they're referred to as colorectal cancers. Rectal cancer begins as small clumps of cells called polyps. Although most polyps are noncancerous (benign), some become cancerous over time. Regular screening to find and remove precancerous polyps can prevent rectal cancer from developing. Changes
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the wall. Do not forget to re-align the binoculars from time to time onto the sun. The moon and stars cannot be observed in this way because the light coming from them is too weak. 2. Sun clock Place a flowerpot with a long stick fixed into the hole at the bottom in a spot, which is sunny, all day. The stick’s shadow moves along the rim of the pot as the sun moves. Each hour by the clock mark the position of the shadow on the pot. If the sun is shining, you can read off the time. Because of
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Until recently most Earth scientists believed that past climate change occurred on relatively long time scales of tens of thousands of years or more Most also thought that climate change was controlled largely by changes in the distribution of solar radiation with Earth's orbital oscillations providing an external forcing to the climate system and pacing the so called Milankovitch cycles However dramatic discoveries during the early s changed this paradigm Climatic records produced from the Greenland
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After the Raptor leaves, Agathon flees into the wilderness and tries to elude Cylon forces, surviving by using anti-radiation injections and the other contents of his survival kit. Eventually, he is captured by a Number Six copy, but is rescued by Valerii (unknown to Agathon, his rescuer is another copy of Cylon model Number Eight).[8] Valerii's true motive in accompanying Agathon is the participation in a Cylon experiment designed to attempt to create a viable Cylon/human hybrid offspring. The Cylons
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caused danger to our society. Examples of this are the texting while driving ban in 39 states and the driving while talking on your cell phone, the hands free law, in 10 states. A growing concern now is the possible health effects of cell phone radiation. Though, nothing is conclusive, a few states jumped in and started proposing for bills to be passed. Cell phone unlocking is a hot topic today. Consumers believe that if you purchase your phone, it is yours to do what you wish. Congress didn’t
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A microscope (from the Ancient Greek "small" "to look" or "see") is an instrument used to see objects that are too small for the naked eye. The science of investigating small objects using such an instrument is calledmicroscopy. Microscopic means invisible to the eye unless aided by a microscope. There are many types of microscopes. The most common (and the first to be invented) is the optical microscope, which uses light to image the sample. Other major types of microscopes are theelectron microscope (both
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MAJOR PROJECT LASER TORCH BASED VOICE TRANSMITTER AND RECEIVER CHAPTER -1 INTRODUCTION 1.1 ABOUT PROJECT LASER TORCH-BASED VOICE TRANSMITTER AND RECEIVER Using this circuit you can communicate with your neighbors wirelessly. Instead of RF signals, light from a laser torch is used as the carrier in the circuit. The laser torch can transmit light up to a distance of about 500 meters. The phototransistor of the receiver must be accurately oriented towards the laser beam from the torch. If there
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CA L I F O R N I A S TA N DA R D S T E S T Released Test Questions Earth Science Introduction - Earth Science The following released test questions are taken from the Earth Science Standards Test. This test is one of the California Standards Tests administered as part of the Standardized Testing and Reporting (STAR) Program under policies set by the State Board of Education. All questions on the California Standards Tests are evaluated by committees of content experts, including teachers
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faces to forested mountain tops and on atolls. Generally the Sali lives in groups. It is a cavity nester. A pair lays up to four eggs and both parents incubate the eggs. They are omnivorous, feeding on seeds, fruit and insects. Description: Glossy black with a short tail and yellow eye as an adult, the Sali is about nine inches or twenty-three centimeters long. Range: The Micronesian Starling is widely distributed in Micronesia ranging through Palau; Yap; Guam; the Commonwealth of the Northern Mariana
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