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Arthur Kantrowitz
Arthur Robert Kantrowitz (October 20, 1913 – November 29, 2008) was an American scientist, engineer, and educator. Kantrowitz grew up in The Bronx and graduated from DeWitt Clinton High School.Overbye, Dennis"Arthur R. Kantrowitz, Whose Wide-Ranging Research Had Many Applications, Is Dead at 95" ''The New York Times'', December 9, 2008. Accessed December 9, 2008. He earned his B.S., M.A. and, in 1947, his Ph.D. degrees in physics from Columbia University. Early life Kantrowitz was born in New York City on October 28, 1913. His mother was a costume designer and his father ran a clinic in the Bronx. As a child, Arthur built an electrocardiograph from old radio parts, working with his brother Adrian (who would go on to perform the first heart transplant in the United States.)Hoffman, Jascha"Dr. Adrian Kantrowitz, Cardiac Pioneer, Dies at 90" ''The New York Times'', November 19, 2008. Accessed November 19, 2008. Career During his graduate studies at Columbia, Kantrowitz s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New York City
New York, often called New York City or NYC, is the List of United States cities by population, most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the List of United States cities by population density, most densely populated major city in the United States, and is more than twice as populous as second-place Los Angeles. New York City lies at the southern tip of New York (state), New York State, and constitutes the geographical and demographic center of both the Northeast megalopolis and the New York metropolitan area, the largest metropolitan area in the world by urban area, urban landmass. With over 20.1 million people in its metropolitan statistical area and 23.5 million in its combined statistical area as of 2020, New York is one of the world's most populous Megacity, megacities, and over 58 million people live within of the city. New York City is a global city, global Culture of New ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hidden Figures (book)
''Hidden Figures: The American Dream and the Untold Story of the Black Women Who Helped Win the Space Race'' is a 2016 nonfiction book written by Margot Lee Shetterly. Shetterly started working on the book in 2010. The book takes place from the 1930s through the 1960s, depicting the particular barriers for Black women in science during this time, thereby providing a lesser-known history of NASA. The biographical text follows the lives of Katherine Johnson, Dorothy Vaughan, and Mary Jackson, three mathematicians who worked as computers (then a job description) at NACA and NASA, during the space race. They overcame discrimination there, as women and as African Americans. Also featured is Christine Darden, who was the first African-American woman to be promoted into the Senior Executive Service for her work in researching supersonic flight and sonic booms. The book reached number one on ''The New York Times'' Non-Fiction Best Sellers list and got the Anisfield-Wolf Book Award ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nobel Prize
The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfred Nobel was a Swedish chemist, engineer, and industrialist most famously known for the invention of dynamite. He died in 1896. In his will, he bequeathed all of his "remaining realisable assets" to be used to establish five prizes which became known as "Nobel Prizes." Nobel Prizes were first awarded in 1901. Nobel Prizes are awarded in the fields of Physics, Chemistry, Physiology or Medicine, Literature, and Peace (Nobel characterized the Peace Prize as "to the person who has done the most or best to advance fellowship among nations, the abolition or reduction of standing armies, and the establishment and promotion of peace congresses"). In 1968, Sveriges Riksbank (Sweden's central bank) funded the establishment of the Prize in Economi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Fusion
Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles ( neutrons or protons). The difference in mass between the reactants and products is manifested as either the release or absorption of energy. This difference in mass arises due to the difference in nuclear binding energy between the atomic nuclei before and after the reaction. Nuclear fusion is the process that powers active or main-sequence stars and other high-magnitude stars, where large amounts of energy are released. A nuclear fusion process that produces atomic nuclei lighter than iron-56 or nickel-62 will generally release energy. These elements have a relatively small mass and a relatively large binding energy per nucleon. Fusion of nuclei lighter than these releases energy (an exothermic process), while the fusion of heavier nuclei results in energy retained by the product nucleons, and the resulting reaction is endo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Total Energy Variometer
In aviation, a variometer – also known as a rate of climb and descent indicator (RCDI), rate-of-climb indicator, vertical speed indicator (VSI), or vertical velocity indicator (VVI) – is one of the flight instruments in an aircraft used to inform the pilot of the rate of descent or climb.Federal Aviation Administration, ''Glider Flying Handbook'', Skyhorse Publishing Inc., 2007 pages 4-7 and 4-8 It can be calibrated in metres per second, feet per minute (1 ft/min = 0.00508 m/s) or knots (1 kn ≈ 0.514 m/s), depending on country and type of aircraft. It is typically connected to the aircraft's external static pressure source. In powered flight, the pilot makes frequent use of the VSI to ascertain that level flight is being maintained, especially during turning maneuvers. In gliding, the instrument is used almost continuously during normal flight, often with an audible output, to inform the pilot of rising or sinking air. It is usual for gliders to be e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supersonic
Supersonic speed is the speed of an object that exceeds the speed of sound ( Mach 1). For objects traveling in dry air of a temperature of 20 °C (68 °F) at sea level, this speed is approximately . Speeds greater than five times the speed of sound (Mach 5) are often referred to as hypersonic. Flights during which only some parts of the air surrounding an object, such as the ends of rotor blades, reach supersonic speeds are called transonic. This occurs typically somewhere between Mach 0.8 and Mach 1.2. Sounds are traveling vibrations in the form of pressure waves in an elastic medium. Objects move at supersonic speed when the objects move faster than the speed at which sound propagates through the medium. In gases, sound travels longitudinally at different speeds, mostly depending on the molecular mass and temperature of the gas, and pressure has little effect. Since air temperature and composition varies significantly with altitude, the speed of s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Conference Of Laser Applications
The International Conference on Lasers and Applications, Lasers 'XX was an annual conference organized by the former Society for Optical and Quantum Electronics. The conference, known in short by ''Lasers 'XX'' (where XX refers to the particular year), was held at various locations in The United States from 1978 to 2000. The emphasis of these conferences was laser development and in particular the development of high-power lasers. The papers delivered at these conferences were published in a series of hard-bound volumes known as ''Proceedings of the International Conference on Lasers 'XX'' () by STS Press. In total, more than 20 book proceedings were published. A particular feature of these conferences was the organization of high-power panel discussions on timely topics of interest, such as the role of lasers in directed energy and the Strategic Defense Initiative (SDI), during the presidency of Ronald Reagan.C. P. Wang, ''Proceedings of the International Conference on La ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rocket Equation
A rocket (from it, rocchetto, , bobbin/spool) is a vehicle that uses jet propulsion to accelerate without using the surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entirely from propellant carried within the vehicle; therefore a rocket can fly in the vacuum of space. Rockets work more efficiently in a vacuum and incur a loss of thrust due to the opposing pressure of the atmosphere. Multistage rockets are capable of attaining escape velocity from Earth and therefore can achieve unlimited maximum altitude. Compared with airbreathing engines, rockets are lightweight and powerful and capable of generating large accelerations. To control their flight, rockets rely on momentum, airfoils, auxiliary reaction engines, gimballed thrust, momentum wheels, deflection of the exhaust stream, propellant flow, spin, or gravity. Rockets for military and recreational uses date back to at least 13th-century China. Signific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laser Propulsion
Laser propulsion is a form of beam-powered propulsion where the energy source is a remote (usually ground-based) laser system and separate from the reaction mass. This form of propulsion differs from a conventional chemical rocket where both energy and reaction mass come from the solid or liquid propellants carried on board the vehicle. History The basic concepts underlying a photon-propelled "sail" propulsion system were developed by Eugene Sanger and the Hungarian physicist György Marx. Propulsion concepts using laser-energized rockets were developed in the 1970s by Arthur Kantrowitz and Wolfgang Moekel, with a variant using laser ablation pioneered by Leik Myrabo.Myrabo, L.N. 1976MHD propulsion by absorption of laser radiation" ''Journal of Spacecraft and Rockets", Vol. 13, 8, pp. 466–472. doi 10.2514/3.27919 An exposition of Kantrowitz's laser propulsion ideas was published in 1988. Laser propulsion systems may transfer momentum to a spacecraft in two different ways. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Dioxide Laser
The carbon-dioxide laser (CO2 laser) was one of the earliest gas lasers to be developed. It was invented by Kumar Patel of Bell Labs in 1964 and is still one of the most useful types of laser. Carbon-dioxide lasers are the highest-power continuous-wave lasers that are currently available. They are also quite efficient: the ratio of output power to pump power can be as large as 20%. The CO2 laser produces a beam of infrared light with the principal wavelength bands centering on 9.6 and 10.6 micrometers (μm). Amplification The active laser medium (laser gain/ amplification medium) is a gas discharge which is air- or water-cooled, depending on the power being applied. The filling gas within a sealed discharge tube consists of around 10–20% carbon dioxide (), around 10–20% nitrogen (), a few percent hydrogen () and/or xenon (Xe), and the remainder is helium (He). A different mixture is used in a ''flow-through'' laser, where is continuously pumped through it. The specific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetohydrodynamics
Magnetohydrodynamics (MHD; also called magneto-fluid dynamics or hydromagnetics) is the study of the magnetic properties and behaviour of electrically conducting fluids. Examples of such magnetofluids include plasmas, liquid metals, salt water, and electrolytes. The word ''magnetohydrodynamics'' is derived from ' meaning magnetic field, ' meaning water, and ' meaning movement. The field of MHD was initiated by Hannes Alfvén, for which he received the Nobel Prize in Physics in 1970. The fundamental concept behind MHD is that magnetic fields can induce currents in a moving conductive fluid, which in turn polarizes the fluid and reciprocally changes the magnetic field itself. The set of equations that describe MHD are a combination of the Navier–Stokes equations of fluid dynamics and Maxwell’s equations of electromagnetism. These differential equations must be solved simultaneously, either analytically or numerically. History The first record ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gas Dynamics
Compressible flow (or gas dynamics) is the branch of fluid mechanics that deals with flows having significant changes in fluid density. While all flows are compressible, flows are usually treated as being incompressible when the Mach number (the ratio of the speed of the flow to the speed of sound) is smaller than 0.3 (since the density change due to velocity is about 5% in that case).Anderson, J.D., ''Fundamentals of Aerodynamics'', 4th Ed., McGraw–Hill, 2007. The study of compressible flow is relevant to high-speed aircraft, jet engines, rocket motors, high-speed entry into a planetary atmosphere, gas pipelines, commercial applications such as abrasive blasting, and many other fields. History The study of gas dynamics is often associated with the flight of modern high-speed aircraft and atmospheric reentry of space-exploration vehicles; however, its origins lie with simpler machines. At the beginning of the 19th century, investigation into the behaviour of fired bullets led to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
