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Vibrational Spectroscopy of Linear Molecules
To determine the vibrational spectroscopy of linear molecules, the rotation and vibration of linear molecules are taken into account to predict which vibrational (normal) modes are active in the infrared spectrum and the Raman spectrum.
  • 531
  • 11 Nov 2022
Biography
Julius Edgar Lilienfeld
Julius Edgar Lilienfeld (April 18, 1882 – August 28, 1963) was a Jewish Austro-Hungarian-born German-American physicist and electronic engineer, credited with the first patents on the field-effect transistor (FET) (1925) and electrolytic capacitor (1931). Because of his failure to publish articles in learned journals and because high-purity semiconductor materials were not available yet, his
  • 1.2K
  • 10 Nov 2022
Topic Review
Large Synoptic Survey Telescope
The Large Synoptic Survey Telescope (LSST) is a wide-field survey reflecting telescope with an 8.4-meter primary mirror, currently under construction, that will photograph the entire available sky every few nights. The word synoptic is derived from the Greek words σύν (syn "together") and ὄψις (opsis "view"), and describes observations that give a broad view of a subject at a particular time. The telescope uses a novel 3-mirror design, a variant of three-mirror anastigmat, which allows a compact telescope to deliver sharp images over a very wide 3.5-degree diameter field of view. Images will be recorded by a 3.2-gigapixel CCD imaging camera, the largest digital camera ever constructed. The telescope is located on the El Peñón peak of Cerro Pachón, a 2,682-meter-high mountain in Coquimbo Region, in northern Chile , alongside the existing Gemini South and Southern Astrophysical Research Telescopes. The LSST Base Facility is located about 100 kilometres (62 mi) away by road, in the town of La Serena. The LSST was proposed in 2001, and construction of the mirror began (with private funds) in 2007. LSST then became the top-ranked large ground-based project in the 2010 Astrophysics Decadal Survey, and the project officially began construction 1 August 2014 when the National Science Foundation (NSF) authorized the FY2014 portion ($27.5 million) of its construction budget. The ceremonial laying of the first stone was performed on 14 April 2015. Site construction began on April 14, 2015, with engineering first light anticipated in 2019, science first light in 2021, and full operations for a ten-year survey commencing in January 2022. LSST, unlike almost all previous large astronomical observatories, has committed to making all data public as soon as it is taken. In their words "By providing immediate public access to all the data it obtains, it will provide everyone, the professional and the “just curious” alike, a deep and frequent window on the entire sky."
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Topic Review
List of Unnumbered Minor Planets: 2002 T–Y
This is a partial list of unnumbered minor planets for principal designations assigned between 1 October 2002 and 31 December 2002 (T–Y).
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  • 10 Nov 2022
Topic Review
Pakistan Institute of Nuclear Science & Technology
Located in Nilore, it maintains a broad portfolio in providing post-graduate and post-doctoral research opportunities in supercomputing, renewable energy, physical, philosophical, materials, environmental, and mathematical sciences. Researchers and scholars are invited from universities throughout Pakistan.
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  • 10 Nov 2022
Topic Review
List of Unnumbered Minor Planets: 2002 P–Q
This is a partial list of unnumbered minor planets for principal designations assigned between 1 August 2002 and 31 August 2002 (P–Q).
  • 372
  • 10 Nov 2022
Topic Review
Gauss' Method
In orbital mechanics (subfield of celestial mechanics), Gauss's method is used for preliminary orbit determination from at least three observations (more observations increases the accuracy of the determined orbit) of the orbiting body of interest at three different times. The required information are the times of observations, the position vectors of the observation points (in Equatorial Coordinate System), the direction cosine vector of the orbiting body from the observation points (from Topocentric Equatorial Coordinate System) and general physical data. Carl Friedrich Gauss developed important mathematical techniques (summed up in Gauss's methods) which were specifically used to determine the orbit of Ceres. The method shown following is the orbit determination of an orbiting body about the focal body where the observations were taken from, whereas the method for determining Ceres' orbit requires a bit more effort because the observations were taken from Earth while Ceres orbits the Sun.
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  • 10 Nov 2022
Topic Review
Bose–Hubbard Model
The Bose–Hubbard model gives a description of the physics of interacting spinless bosons on a lattice. It is closely related to the Hubbard model which originated in solid-state physics as an approximate description of superconducting systems and the motion of electrons between the atoms of a crystalline solid. The model was first introduced by Gersch and Knollman in 1963 in the context of granular superconductors. (The term 'Bose' in its name refers to the fact that the particles in the system are bosonic.) The model rose to prominence in the 1980s after it was found to capture the essence of the superfluid-insulator transition in a way that was much more mathematically tractable than fermionic metal-insulator models. The Bose–Hubbard model can be used to describe physical systems such as bosonic atoms in an optical lattice, as well as certain magnetic insulators. Furthermore, it can also be generalized and applied to Bose–Fermi mixtures, in which case the corresponding Hamiltonian is called the Bose–Fermi–Hubbard Hamiltonian.
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Topic Review
Energy Accidents
Energy resources bring with them great social and economic promise, providing financial growth for communities and energy services for local economies. However, the infrastructure which delivers energy services can break down in an energy accident, sometimes causing much damage, and energy fatalities can occur, and with many systems often deaths will happen even when the systems are working as intended. Historically, coal mining has been the most dangerous energy activity and the list of historical coal mining disasters is a long one. Underground mining hazards include suffocation, gas poisoning, roof collapse and gas explosions. Open cut mining hazards are principally mine wall failures and vehicle collisions. In the US alone, more than 100,000 coal miners have been killed in accidents over the past century, with more than 3,200 dying in 1907 alone. According to Benjamin K. Sovacool, 279 major energy accidents occurred from 1907 to 2007 and they caused 182,156 deaths with $41 billion in property damages, with these figures not including deaths from smaller accidents. However, by far the greatest energy fatalities that result from energy generation by humanity, is the creation of air pollution. The most lethal of which, particulate matter, which is primarily generated from the burning of fossil fuels and biomass is (counting outdoor air pollution effects only) estimated to cause 2.1 million deaths annually.
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Topic Review
Virtual Breakdown Mechanism
The Virtual breakdown mechanism is a concept in the field of electrochemistry. In electrochemical reactions, when the cathode and the anode are close enough to each other (i.e., so-called "nanogap electrochemical cells"), the double layer the regions from the two electrodes is overlapped, forming a large electric field uniformly distributed inside the entire electrode gap. Such high electric fields can significantly enhance the ion migration inside bulk solutions and thus increase the entire reaction rate, akin to the "breakdown" of the reactant(s). However, it is fundamentally different from the traditional "breakdown". The Virtual breakdown mechanism was discovered in 2017 when researchers studied pure water electrolysis based on deep-sub-Debye-length nanogap electrochemical cells. Furthermore, researchers found the relation of the gap distance between cathodes and anodes to the performance of electrochemical reactions.
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