A light-emitting diode (LED) is a semiconductor light source.[6] LEDs are used as indicator lamps in many devices and are increasingly used for other lighting. Appearing as practical electronic components in 1962‚[7] 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 switched on‚ electrons are able to recombine with holes within the device‚ releasing energy
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discovery of penicillin. this has help society to understand the causes of disease‚ and the ways to tackle it. These discoveries began in the 1800s‚ where doctors at the time were just beginning to speculate about germs and microbes with a new invention‚ the microscope. the microscope can see what is invisible to human eye and it was good use for identifying micro organism as they were incredibly small. those doctors who believed germs existed thought they were the result of disease and not the
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structures depended on the extraction of mined materials. Early civilizations depended upon sheer labor to extract these materials. This was shown to be very labor and time intensive. Especially early on when stone tools were the only thing available. The solution to this problem came in the late 1800s with the invention of dynamite. Gunpowder is considered the first explosive to be discovered. It was first discovered many years ago in China and India. Early uses of gunpowder were primarily for military use
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Introduction Identification and classification of bacteria is important to make easier manipulation on the bacteria for various purposes such as for medical‚ research‚ developmental‚ and biotechnicalfieldsThe cell wall is the basis for classification of bacteria according to the Gram stain. Accordingto the chemical make up of bacterial cell wall‚ a staining procedure‚ Gram stain‚ helps usclassify bacteria into two subgroups‚ The cell wall can stain either positive or negative‚depending on its chemistry
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Sarah E. Goode‚ born in 1855‚ was the first African American woman to receive a United States patent. Her invention was a cabinet bed. When the bed was not in use‚ the invention also functioned as a roll-top desk. During the time of its invention‚ people commonly lived in studios or small apartments. Most people did not have the space for bulky or large pieces of furniture because there was little space in there homes as it was. However‚ the cabinet desk was an ideal piece of furniture because it
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The Invention of the DVD Many people enjoy watching or listening to DVDs every day. Now people can see more than just the movie. They can enjoy many different special features or quickly go to a certain spot in the movie without having to rewind or fast forward. Many people do not know how this invention came to be. Who invented the DVD and how did they do it? What are the different types DVDs? The invention we enjoy today only exists because of the hard work of many people. The DVD was
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Laziness is the Mother of all Inventions I think it was Isaac Newton who said. “Necessity is the mother of all inventions”. I beg to differ. In my opinion‚ Laziness is the mother of all inventions. Consider the original lazy caveman. All the hardworking cavemen were busy sneaking through the bushes in the hot sun‚ risking lives trying to catch animals without any tools. But then there was this lazy caveman who thought‚ “Hunting is too much hard work. I think I should come up with something to make
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the most important technology evolutions‚ Greece and Rome both had an impact on technology evolution. Most of their inventions and discoveries are still used today. Throughout the history of Rome‚ the Romans intelligence served them well with inventions like aqueducts‚ bound books‚ money‚ newspapers‚ or even concrete. However‚ the same could be said about Greece. The Greeks inventions consisted of the water mill‚ alarm clock‚ and basics of modern science. Romans technology changed more drastically
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abstract of the document here. The abstract is typically a short summary of the contents of the document.] | Ancient Chinese inventions have had a huge impact on the modern world as we know it. Numerous technological and cultural advancements have spawned off from the inventions derived from Ancient China‚ which spans over thousands of years ago. A lot of the inventions really attest to how more advanced Ancient China was in science and technology. In the world today‚ they still symbolize excellence
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The Airplane: Public Reaction Wilbur and Orville Wright invented the world’s first airplane at the turn of the twentieth century. Mary Bellis described the years following the brothers’ discovery‚ during which various engineers furthered their invention to where it stands today‚ capable of intercontinental travel for commercial‚ transportation and militaristic use. The airplane’s introduction and advancement was first met with apathy‚ then with both praise and criticism from people of varying social
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