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Electron Lens
Transmission electron microscopy (TEM) is a microscopy technique in which a beam of electrons is transmitted through a specimen to form an image. The specimen is most often an ultrathin section less than 100 nm thick or a suspension on a grid. An image is formed from the interaction of the electrons with the sample as the beam is transmitted through the specimen. The image is then magnified and Focus (optics), focused onto an imaging device, such as a fluorescent screen, a layer of photographic film, or a Detectors for transmission electron microscopy, detector such as a scintillator attached to a charge-coupled device or a direct electron detector. Transmission electron microscopes are capable of imaging at a significantly higher Optical resolution, resolution than Optical microscope, light microscopes, owing to the smaller de Broglie wavelength of electrons. This enables the instrument to capture fine detail—even as small as a single column of atoms, which is thousands o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polio EM PHIL 1875 Lores
Poliomyelitis ( ), commonly shortened to polio, is an infectious disease caused by the poliovirus. Approximately 75% of cases are asymptomatic; mild symptoms which can occur include sore throat and fever; in a proportion of cases more severe symptoms develop such as headache, neck stiffness, and paresthesia. These symptoms usually pass within one or two weeks. A less common symptom is permanent Flaccid paralysis, paralysis, and possible death in extreme cases.. Years after recovery, post-polio syndrome may occur, with a slow development of muscle weakness similar to what the person had during the initial infection. Polio occurs naturally only in humans. It is highly infectious, and is spread from person to person either through fecal–oral route, fecal–oral transmission (e.g. poor hygiene, or by ingestion of food or water contaminated by human feces), or via the oral–oral route. Those who are infected may spread the disease for up to six weeks even if no symptoms are pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollution
Pollution is the introduction of contaminants into the natural environment that cause harm. Pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light). Pollutants, the components of pollution, can be either foreign substances/energies or naturally occurring contaminants. Although environmental pollution can be caused by natural events, the word pollution generally implies that the contaminants Human impact on the environment, have a human source, such as manufacturing, Extractivism, extractive industries, poor waste management, transportation or Agricultural pollution, agriculture. Pollution is often classed as point source pollution, point source (coming from a highly concentrated specific site, such as a factory, Environmental effects of mining, mine, construction site), or nonpoint source pollution (coming from a widespread distributed sources, such as microplastics or agricultural runoff). Many sources of po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ultraviolet
Ultraviolet radiation, also known as simply UV, is electromagnetic radiation of wavelengths of 10–400 nanometers, shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight and constitutes about 10% of the total electromagnetic radiation output from the Sun. It is also produced by electric arcs, Cherenkov radiation, and specialized lights, such as mercury-vapor lamps, tanning lamps, and black lights. The photons of ultraviolet have greater energy than those of visible light, from about 3.1 to 12 electron volts, around the minimum energy required to ionize atoms. Although long-wavelength ultraviolet is not considered an ionizing radiation because its photons lack sufficient energy, it can induce chemical reactions and cause many substances to glow or fluoresce. Many practical applications, including chemical and biological effects, are derived from the way that UV radiation can interact with organic molecules. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wavelength
In physics and mathematics, wavelength or spatial period of a wave or periodic function is the distance over which the wave's shape repeats. In other words, it is the distance between consecutive corresponding points of the same ''phase (waves), phase'' on the wave, such as two adjacent crests, troughs, or zero crossings. Wavelength is a characteristic of both traveling waves and standing waves, as well as other spatial wave patterns. The multiplicative inverse, inverse of the wavelength is called the ''spatial frequency''. Wavelength is commonly designated by the Greek letter lambda (''λ''). For a modulated wave, ''wavelength'' may refer to the carrier wavelength of the signal. The term ''wavelength'' may also apply to the repeating envelope (mathematics), envelope of modulated waves or waves formed by Interference (wave propagation), interference of several sinusoids. Assuming a sinusoidal wave moving at a fixed phase velocity, wave speed, wavelength is inversely proportion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diffraction Limit
In optics, any optical instrument or systema microscope, telescope, or camerahas a principal limit to its resolution due to the physics of diffraction. An optical instrument is said to be diffraction-limited if it has reached this limit of resolution performance. Other factors may affect an optical system's performance, such as lens imperfections or aberrations, but these are caused by errors in the manufacture or calculation of a lens, whereas the diffraction limit is the maximum resolution possible for a theoretically perfect, or ideal, optical system. The diffraction-limited angular resolution, in radians, of an instrument is proportional to the wavelength of the light being observed, and inversely proportional to the diameter of its objective's entrance aperture. For telescopes with circular apertures, the size of the smallest feature in an image that is diffraction limited is the size of the Airy disk. As one decreases the size of the aperture of a telescopic lens, dif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ernst Abbe
Ernst Karl Abbe (23 January 1840 – 14 January 1905) was a German businessman, optical engineer, physicist, and social reformer. Together with Otto Schott and Carl Zeiss, he developed numerous optical instruments. He was also a co-owner of Carl Zeiss AG, a German manufacturer of scientific microscopes, astronomical telescopes, planetariums, and other advanced optical systems. Personal life Abbe was born 23 January 1840 in Eisenach, Saxe-Weimar-Eisenach, to Georg Adam Abbe and Elisabeth Christina Barchfeldt. He came from a humble home – his father was a foreman in a spinnery. Supported by his father's employer, Abbe was able to attend secondary school and to obtain the general qualification for university entrance with fairly good grades, at the Eisenach Gymnasium, which he graduated from in 1857. By the time he left school, his scientific talent and his strong will had already become obvious. Thus, in spite of the family's strained financial situation, his father decide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ernst Ruska Electron Microscope - Deutsches Museum - Munich-edit
Ernst is both a surname and a given name, the German, Dutch, and Scandinavian form of Ernest. Notable people with the name include: Surname * Adolf Ernst (1832–1899) German botanist known by the author abbreviation "Ernst" * Anton Ernst (born 1975), South African film producer * Alice Henson Ernst (1880-1980), American writer and historian * Bastian Ernst (born 1987), German politician * Britta Ernst (born 1961), German politician * Cornelia Ernst (born 1956), German politician * Edzard Ernst (born 1948), German-British academic * Emil Ernst (1889–1942), astronomer * Ernie Ernst (1924/25–2013), American judge * Eugen Ernst (1864–1954), German politician * Fabian Ernst (born 1979), German soccer player * Fedir Ernst (1891-1942), Ukrainian art historian * Gustav Ernst (born 1944), Austrian writer * Heinrich Wilhelm Ernst (1812–1865), Moravian violinist and composer * Jim Ernst (born 1942), Canadian politician * Jimmy Ernst (1920–1984), American painter, so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nobel Prize In Physics
The Nobel Prize in Physics () is an annual award given by the Royal Swedish Academy of Sciences for those who have made the most outstanding contributions to mankind in the field of physics. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901, the others being the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and Nobel Prize in Physiology or Medicine. Physics is traditionally the first award presented in the Nobel Prize ceremony. The prize consists of a medal along with a diploma and a certificate for the monetary award. The front side of the medal displays the same profile of Alfred Nobel depicted on the medals for Physics, Chemistry, and Literature. The first Nobel Prize in Physics was awarded to German physicist Wilhelm Röntgen in recognition of the extraordinary services he rendered by the discovery of X-rays. This award is administered by the Nobel Foundation and is widely regarded as the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ernst Ruska
Ernst August Friedrich Ruska (; 25 December 1906 – 27 May 1988) was a German physicist who won the Nobel Prize in Physics in 1986 for his work in electron optics, including the design of the first electron microscope. Life and career Ernst Ruska was born in Heidelberg, Germany. He was educated at the Technical University of Munich from 1925 to 1927 and then entered ''Technische Hochschule Berlin'' (now Technische Universität Berlin), where he posited that microscopes using electrons, with wavelengths 1000 times shorter than those of light, could provide a more detailed picture of an object than a microscope utilizing light, in which magnification is limited by the size of the wavelengths. In 1931, he demonstrated that a magnetic coil could act as an electron lens, and used several coils in a series to build the first electron microscope in 1933. After completing his PhD in 1933, Ruska continued to work in the field of electron optics, first at Fernseh AG in Berlin-Zehlendo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Max Knoll
Max Knoll (17 July 1897 – 6 November 1969) was a German electrical engineer and co-inventor of the electron microscope. Knoll was born in Wiesbaden and studied at the University of Munich and at the Technischen Hochschulen in Munich and Berlin-Charlottenburg, where he obtained his doctorate in the Institute for High Voltage Technology. In 1927 he became the leader of the electron research group there, where he and his co-worker, Ernst Ruska, invented the electron microscope in 1931. In April 1932, Knoll joined Telefunken in Berlin to do developmental work in the field of television design. He was also a private lecturer in Berlin. After World War II, Knoll joined the University of Munich as an extraordinary professor and director of the Institute for Electromedicine. He moved to the USA in 1948, to work at the Department of Electrical Engineering at Princeton University. In 1956 he returned to Munich and engaged in a series of experiments at the Technische Hochschule, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palynology
Palynology is the study of microorganisms and microscopic fragments of mega-organisms that are composed of acid-resistant organic material and occur in sediments, sedimentary rocks, and even some metasedimentary rocks. Palynomorphs are the microscopic, acid-resistant organic remains and debris produced by a wide variety of plants, animals, and Protista that have existed since the late Proterozoic.Neuendorf, K.K.E., J.P. Mehl, Jr., and J.A. Jackson, eds., 2005, ''Glossary of Geology'' (5th ed.). Alexandria, Virginia, American Geological Institute. 779 pp. It is the science that studies contemporary and fossil palynomorphs (paleopalynology), including pollen, spores, orbicules, dinocysts, acritarchs, chitinozoans and scolecodonts, together with particulate organic matter (POM) and kerogen found in sedimentary rocks and sediments. Palynology does not include diatoms, foraminiferans or other organisms with siliceous or calcareous tests. The name of the science and o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
