In April 1, 2002, organic light emitting diodes gain rise in the scientific community with their published, more practical form at Ames Laboratory.
“Scientists at the U.S. Department of Energy's Ames Laboratory, in collaboration with scientists at the University of Michigan, Ann Arbor, have developed and demonstrated a novel, fluorescence-based chemical sensor that is more compact, versatile and less expensive than existing technology of its kind. The new sensor holds promise for myriad potential applications, such as monitoring oxygen, inorganic gases, volatile organic compounds, biochemical compounds, and biological organisms.”(Johnston).
Ames Laboratory has been a driving force in OLED research and finally produced an effective model. Generally, OLEDs have a layer of organic materials placed between an anode and cathode, all deposited on a substrate. In the organic layer there is an emissive layer, which emits electrons easily, and a conductive layer, which has electrons removed. OLEDs operate through electrophosphorescence and thus have a similar process to what we covered; a voltage excites a species, which transfers to a different spin orbital and then drops to ground state to emit a photon.
First, a voltage is applied across the OLED causing a current of electrons to flow from cathode to anode and through the organic layer. The cathode gives electrons to the emissive layer of organic molecules. The anode removes electrons from the conductive layer of organic molecules, which creates “holes” or gaps. At the boundary between the emissive and the conductive layers, electrons find the “holes”. Electrons fill the holes by falling into a different spin state, matching the atom that's missing an electron. The electron then...
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Absorbance was defined as: log I_o/I where I_o is incident light and I is the transmitted light. Fluorescence emission spectrum is different from fluorescence excitation spectrum because it records different wavelengths of chemical s...
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...ross section, larger photostabilty and higher quantum efficiency of the detectors , impurities being prebleached and removing of the background fluorescence using pinhole arrangements in the conjugate plane <<23. The above principles are implemented using either wide field methods or point detection methods which are completely application specific. Where on one hand confocal microscopy (a point detection method) has the advantage of attaining high signal is to noise ratio and high resolution but the drawback of unable to analyze numerous mobile molecules at a time <<23. On the other hand, using wide field epi- illumination excitation techniques coupled with CCD detection can probe several mobile molecules at once but has poor noise is to signal resolution and weak temporal resolution <
The Web. The Web. 04 Feb. 2010. http://www.shmoop.com/wwi/science-technology.html>. "
...p water/luminol solution were added to each of four wells. Five drops of the reagents were then added to each well. Chemiluminescence was not observed in any well.
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The purpose of this lab was to analyse how light and color is created inside an atom in order to deduce what an unknown chemical compound was. We did two different experiments in order to examine how light is created and changed. In one, we looked at how chemical compounds affected a flame’s color, and to determine what the unknown salt contains. In the other lab, we looked at how atoms create light, and how it is displayed on the elements individual spectral line.
3) Stokes shift - Generally the emitted fluorescent light has a longer wavelength and lower energy than the absorbed light. This phenomenon is known as Stokes shift. It is due to the loss of energy between the time a photon is absorbed and when it is emitted.
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The incandescent lamp has been around since its beginning stages in the 19th century. The chapter titled “Incandescent lamps” in the book Revolution in Lamps:...
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As a graduate student, I will undertake research and coursework in Electrical Engineering to enhance my competencies in this field. I intend to complete my master's degree in order to pursue my doctorate. The research that I am most interested in pursuing at Northeastern University surrounds the optical properties of MEMS devices, and the development of substrate-based fast electro-optical interfaces. My interest in this area stems from my undergraduate study in MEMs development for tri-axial accelerometers.
Kennedy, Gerry. "The Spectronics Blog." The Spectronics Blog RSS. Spectronicsinoz, 15 May 2012. Web. 04 Mar. 2014.
Today there are many technological advancement to enhance our daily activities, whether it be as simple as an Ipod for entertainment purposes or as vital as an artificial heart for the survival of a human live, science and technology is the reason for its existence.