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#676 2020-02-08 00:43:12

ganesh
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Re: crème de la crème

642) Gregory Pincus

Gregory Pincus, in full Gregory Goodwin Pincus, (born April 9, 1903, Woodbine, New Jersey, U.S.—died August 22, 1967, Boston, Massachusetts), American endocrinologist whose work on the antifertility properties of steroids led to the development of the first effective birth-control pill.

Pincus was educated at Cornell University and Harvard University (M.S., Sc.D., 1927) and also studied in England and Germany. He was a faculty member at Harvard (1931–38), Clark University in Worcester, Massachusetts (1938–45), Tufts Medical School in Medford, Massachusetts (1946–50), and Boston University (1950–67).

In 1944 Pincus and Hudson Hoagland founded the Worcester Foundation for Experimental Biology, which became an important centre for the study of steroid hormones and mammalian reproduction. Margaret Sanger encouraged his work, and in 1951 Pincus and his collaborators began to work with synthesized hormones and the prevention of pregnancy. They found that inhibition of ovulation was an effective means of preventing pregnancy in laboratory animals and moved to perfect an oral contraceptive for women.

Pincus’s publications include ‘The Eggs of Mammals’ (1936) and ‘The Control of Fertility’ (1965). He also edited a number of monographs on aspects of hormones.

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It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi. 

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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#677 2020-02-10 01:05:13

ganesh
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Re: crème de la crème

643) George Constantinescu


George Constantinescu, (first name's diminutive is Gogu, last name also Constantinesco; 4 October 1881 – 11 December 1965) was a Romanian scientist, engineer and inventor. During his career, he registered over 130 inventions. He is the creator of the ‘theory of sonics’, a new branch of continuum mechanics, in which he described the transmission of mechanical energy through vibrations.

Born in Craiova in "the Doctor's House" near the Mihai Bravu Gardens, he was influenced by his father George, born in 1844 (a professor of mathematics and engineering science, specialized in mathematics at the Sorbonne University). Gogu Constantinescu settled in the United Kingdom in 1912. He was an honorary member of the Romanian Academy.

Family

He married Alexandra (Sandra) Cocorescu in Richmond, London, in December 1914. The couple moved to Wembley and, after their son Ian was born, they moved to Weybridge. The marriage broke down in the 1920s and ended in divorce. He then married Eva Litton and the couple moved to Oxen House, beside Lake Coniston. Eva had two children, Richard and Michael, by a previous marriage.

Inventions and designs

Synchronization gear

His hydraulic machine gun synchronization gear allowed airplane-mounted guns to shoot between the spinning blades of the propeller. The Constantinesco synchronization gear (or "CC" gear) was first used operationally on the D.H.4s of No. 55 squadron R.F.C. from March 1917, during World War I, and rapidly became standard equipment, replacing a variety of mechanical gears. It continued to be used by the Royal Air Force until World War II – the Gloster Gladiator being the last British fighter to be equipped with "CC" gear.

Sonics

In 1918, he published the book ‘A treatise on transmission of power by vibrations’  in which he described his Theory of sonics. The theory is applicable to various systems of power transmission but has mostly been applied to hydraulic systems. Sonics differs from hydrostatics, being based on waves, rather than pressure, in the liquid. Constantinescu argued that, contrary to popular belief, liquids are compressible. Transmission of power by waves in a liquid (e.g. water or oil) required a generator to produce the waves and a motor to use the waves to do work, either by percussion (as in rock drills) or by conversion to rotary motion.
Internal combustion engines

He had several patents for improvements to carburetors, for example US1206512. He also devised a hydraulic system (patent GB133719) for operating both the valves and the fuel injectors for diesel engines.

Torque converter

He invented a mechanical torque converter actuated by a pendulum. This was applied to the Constantinesco, a French-manufactured car. It was also tried on rail vehicles. A 250 hp petrol engined locomotive with a Constantinescu torque converter was exhibited at the 1924 Wembley Exhibition. The system was not adopted on British railways but it was applied to some railcars on the Romanian State Railways.

Other

Other inventions included a "railway motor wagon". The latter ran on normal flanged steel wheels but the drive used a road vehicle powertrain with rubber tyres pressed against the rails. This is similar to the system used on many modern road-rail vehicles. He also designed the Constanţa Mosque (a project completed by the architect Victor Ştefănescu).

Recent developments

Research on a ‘sonic asynchronous motor for vehicle applications’ (based on Constantinescu's work) has been done at the Transilvania University of Brașov. The date of the paper is believed to be 5 October 2010.

Death

He died at Oxen House, beside Coniston Water on 11/12 December 1965, and is buried in the churchyard at Lowick, Cumbria.

Recognition

The Dimitrie Leonida Technical Museum in Bucharest has exhibits relating to George Constantinescu.

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It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi. 

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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#678 2020-02-12 00:34:28

ganesh
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Re: crème de la crème

644) Sir Henry Cole

Sir Henry Cole (15 July 1808 – 18 April 1882) was a British civil servant and inventor who facilitated many innovations in commerce and education in 19th century in the United Kingdom. Cole is credited with devising the concept of sending greetings cards at Christmas time, introducing the world's first commercial Christmas card in 1843.

Biography

The world's first commercially produced Christmas card, made by Henry Cole 1843.

Henry Cole was born in Bath the son of Captain Henry Robert Cole, then of the 1st Dragoon Guards, and his wife Lætitia Dormer. He was sent in 1817 to Christ's Hospital, and upon leaving school in 1823 became clerk to Francis Palgrave, and then a sub-commissioner under the Record Commission. Cole was employed in transcribing records, but found time to study water-colour painting under David Cox, and exhibited sketches at the Royal Academy. He lived with his father in a house belonging to the novelist Thomas Love Peacock, who retained two rooms in it, and became a friend of young Cole. Cole drew for him, helped him in writing critiques of musical performances, and was introduced by him to John Stuart Mill, Charles Buller, and George Grote. The friends used to meet at Grote's house in Threadneedle Street for discussions twice a week. A new Record Commission was issued in 1831, and in 1833 Cole was appointed a sub-commissioner. The secretary, Charles Purton Cooper, quarrelled with the commission, and with Cole, who applied to Charles Buller for protection. A committee of the House of Commons was appointed upon Buller's motion in 1836, which reported against the existing system, and the commission lapsed on the death of William IV on 20 June 1837. Cole wrote many articles in support of Buller. He was appointed by Lord Langdale, who, as Master of the Rolls, administered the affairs of the commission, to take charge of the records of the exchequer of pleas.

The record office was constituted in 1838 under the Public Record Office Act 1838, and Cole became one of the four senior assistant-keepers. He ranged a large mass of records in the Carlton House Riding School, where he was placed for the purpose 2 November 1841. His reports upon the unsuitability of this place contributed to bring about the erection of the building in Fetter Lane (begun in 1851). Cole's duties at the record office did not absorb his whole energy. In 1838, with the leave of his superiors, he became secretary to a committee for promoting postal reform. He edited their organ, the Post Circular, suggested by himself, of which the first number appeared 14 March 1838. He got up petitions and meetings with such energy that Cobden offered to him in 1839 the secretaryship of the Anti-Cornlaw League.
Parliament granted power to carry out the new postal scheme in August 1839, and the treasury offered premiums for the best proposals as to stamps. Cole gained one of the premiums; he attended the treasury to discuss details, and was employed there till the beginning of 1842 in working out the scheme.

From 1837 to 1840, he worked as an assistant to Rowland Hill and played a key role in the introduction of the Penny Post. He is sometimes credited with the design of the world's first postage stamp, the Penny Black.

In 1843, Cole introduced the world's first commercial Christmas card, commissioning artist John Callcott Horsley to make the artwork.

Felix Summerly pseudonym

Cole was personally interested in industrial design, and under the pseudonym Felix Summerly designed a number of items which went into production, including a prize-winning teapot manufactured by Minton. As Felix Summerly, he also wrote a series of children's books, including 'The home treasury' (1843-1855); 'A hand-book for the architecture, sculpture, tombs, and decorations of Westminster Abbey' (1859); 'Beauty and the beast: an entirely new edition' (1843); 'An Alphabet of Quadrupeds' (1844); and 'The pleasant history of Reynard the Fox, told by the pictures by Albert van Everdingen' (1843).

Cole and the exhibitions

Through his membership of the Society for the Encouragement of Arts, Manufactures, and Commerce, Cole lobbied government for support for his campaign to improve standards in industrial design. The backing of Prince Albert was secured, and in 1847 a royal charter was granted to the Royal Society for the Encouragement of Arts, Manufactures and Commerce (RSA). Under the patronage of Prince Albert, Cole organised a successful Exhibition of Art Manufactures in 1847, with enlarged exhibitions following in 1848 and 1849.

Cole visited the 1849 11th Quinquennial Paris Exhibition and noticed the lack of an exhibition open to international participants. He saw that the RSA's planned exhibitions for 1850 and 1851 could be adapted into a larger international exhibition, and he secured the backing of Queen Victoria to establish in 1850 the Royal Commission for the Exhibition of 1851 to manage the new exhibition, under the Presidency of Prince Albert.

The Great Exhibition of the Works of Industry of all Nations was held in the Crystal Palace in Hyde Park, London, from 1 May to 15 October 1851, and was an enormous popular and financial success, partially due to the astute management of Henry Cole.

Museums

As one of the Commissioners, Cole was instrumental in the decision that the £186,000 surplus from the Great Exhibition would be used for improving science and art education in the United Kingdom. Land was purchased in the South Kensington area and developed as the centre for a number of educational and cultural institutions, known half-jokingly as "Albertopolis". Henry Cole was appointed the first General Superintendent of the Department of Practical Art, set up by the government to improve standards of art and design education in Britain with reference to their applicability to industry. In this capacity he was instrumental in the development of the Victoria and Albert Museum which had begun as the Museum of Ornamental Art in Marlborough House. Cole oversaw its move to its current site, and became first director of what was called South Kensington Museum from 1857 to 1873. In 1974 a part of the museum that was once known as the Huxley Building was renamed the Henry Cole Building; today it forms the Henry Cole Wing of the V&A.

Honours and legacy

Cole was instrumental in the development of the National Art Training School (renamed the Royal College of Art in 1896) and played a part in the establishment of many other South Kensington institutions, such as the Royal College of Music and Imperial College London. In fact, the Imperial College Mathematics Department was formerly based in the Henry Cole Wing on Exhibition Road, before the premises were donated to the Victoria & Albert Museum.

Cole was awarded the CB for his work on the Great Exhibition and was knighted by Queen Victoria in 1875. Often referred to in the press as "Old King" Cole, he was known to have the closest personal backing of the Queen and especially of the Prince Consort, who when he needed a facilitator for one of his pet projects, was heard to remark: "We must have steam, get Cole".

An English heritage blue plaque commemorates where Cole lived and worked at 33 Thurloe Square, South Kensington, London, opposite the Victoria and Albert Museum.

In 2001, one of Cole's first Christmas cards, which was sent to his grandmother in 1843, sold at auction for £22,500.

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It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi. 

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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#679 2020-02-14 00:51:25

ganesh
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Re: crème de la crème

645) Charles Chamberland

Charles Chamberland (12 March 1851 – 2 May 1908) was a French microbiologist from Chilly-le-Vignoble in the department of Jura who worked with Louis Pasteur.

In 1884 he developed a type of filtration known today as the Chamberland filter or Chamberland-Pasteur filter, a device that made use of an unglazed porcelain bar. The filter had pores that were smaller than bacteria, thus making it possible to pass a solution containing bacteria through the filter, and having the bacteria completely removed from the solution. Chamberland was also credited for starting a research project that led to the invention of the autoclave device in 1879.

He worked with Pasteur and came up, by chance, with a vaccine for chicken cholera. He went away on holiday, forgetting to inject the disease into some chickens as he had been told. When he came back he saw the jar of bacteria sitting on the side and thought he would inject it into the chickens anyway. To his amazement they did not die. He reported this to Pasteur, who told him to inject a fresh form into the chickens. He went on to inject the fresh form into the same chickens, and they didn't die. He had found a vaccine. They had also discovered that a weakened form of a disease could act as a vaccine.

(A Chamberland filter, also known as a Pasteur–Chamberland filter, is a porcelain water filter invented by Charles Chamberland in 1884. It was developed after Henry Doulton's ceramic water filter of 1827. It is similar to the Berkefeld filter in principle.)

(An autoclave is a pressure chamber used to carry out industrial and scientific processes requiring elevated temperature and pressure in relation to ambient. Autoclaves are used in medical applications to perform sterilization and in the chemical industry to cure coatings and vulcanize rubber and for hydrothermal synthesis. Industrial autoclaves are used in industrial applications, especially in the manufacturing of composites.

Many autoclaves are used to sterilize equipment and supplies by subjecting them to pressurized saturated steam at 121 °C (250 °F) for around 15–20 minutes depending on the size of the load and the contents  The autoclave was invented by Charles Chamberland in 1884, although a precursor known as the steam digester was created by Denis Papin in 1679. The name comes from Greek auto-, ultimately meaning self, and Latin clavis meaning key, thus a self-locking device.)

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It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi. 

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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#680 2020-02-16 00:58:56

ganesh
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Re: crème de la crème

646) Sir Julian Huxley

Sir Julian Huxley, in full Sir Julian Sorell Huxley, (born June 22, 1887, London—died Feb. 14, 1975, London), English biologist, philosopher, educator, and author who greatly influenced the modern development of embryology, systematics, and studies of behaviour and evolution.

Julian, a grandson of the prominent biologist T.H. Huxley, a brother of novelist Aldous Huxley, and the oldest son of the biographer and man of letters Leonard Huxley, was educated at Eton and Balliol College, Oxford. His scientific research included important work on hormones, developmental processes, ornithology, and ethology. He developed and headed the biology department at the newly formed Rice University in Houston, Texas, before serving in the British Army Intelligence Corps between 1916 and the end of World War I. He later became professor of zoology at King’s College, London University; served for seven years as secretary to the Zoological Society of London, transforming the zoo at Regent’s Park and being actively involved in the development of that at Whipsnade in Bedfordshire; and became a Fellow of the Royal Society. He is perhaps best known among biologists for coining the term “evolutionary synthesis” to refer to the unification of taxonomy, genetics, and Darwinian theory in the 1940s. He was the first director general of the United Nations Educational, Scientific and Cultural Organization (UNESCO) in 1946–48. He was knighted in 1958. In 1961 he cofounded the World Wildlife Fund for Nature. A biography “The Huxleys” by Ronald W. Clark was published in 1968.

In 1919 Huxley married Marie Juliette Baillot, daughter of a Swiss lawyer, by whom he had two sons: Anthony Julian Huxley, who conducted valuable operational research on aircraft, became an authority on exotic garden plants, and produced the standard encyclopaedia on mountains, and Francis Huxley, who became a lecturer in social anthropology at Oxford.

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It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi. 

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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#681 2020-02-18 00:57:29

ganesh
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Re: crème de la crème

647) Rosalind Franklin

Rosalind Franklin, in full Rosalind Elsie Franklin, (born July 25, 1920, London, England—died April 16, 1958, London), British scientist best known for her contributions to the discovery of the molecular structure of deoxyribonucleic acid (DNA), a constituent of chromosomes that serves to encode genetic information. Franklin also contributed new insight on the structure of viruses, helping to lay the foundation for the field of structural virology.

Franklin attended St. Paul’s Girls’ School before studying physical chemistry at Newnham College, University of Cambridge. After graduating in 1941, she received a fellowship to conduct research in physical chemistry at Cambridge. But the advance of World War II changed her course of action: not only did she serve as a London air raid warden, but in 1942 she gave up her fellowship in order to work for the British Coal Utilisation Research Association, where she investigated the physical chemistry of carbon and coal for the war effort. Nevertheless, she was able to use this research for her doctoral thesis, and in 1945 she received a doctorate from Cambridge. From 1947 to 1950 she worked with Jacques Méring at the State Chemical Laboratory in Paris, studying X-ray diffraction technology. That work led to her research on the structural changes caused by the formation of graphite in heated carbons—work that proved valuable for the coking industry.

In 1951 Franklin joined the Biophysical Laboratory at King’s College, London, as a research fellow. There she applied X-ray diffraction methods to the study of DNA. When she began her research at King’s College, very little was known about the chemical makeup or structure of DNA. However, she soon discovered the density of DNA and, more importantly, established that the molecule existed in a helical conformation. Her work to make clearer X-ray patterns of DNA molecules laid the foundation for James Watson and Francis Crick to suggest in 1953 that the structure of DNA is a double-helix polymer, a spiral consisting of two DNA strands wound around each other.

From 1953 to 1958 Franklin worked in the Crystallography Laboratory at Birkbeck College, London. While there she completed her work on coals and on DNA and began a project on the molecular structure of the tobacco mosaic virus. She collaborated on studies showing that the ribonucleic acid (RNA) in that virus was embedded in its protein rather than in its central cavity and that this RNA was a single-strand helix, rather than the double helix found in the DNA of bacterial viruses and higher organisms. Franklin’s involvement in cutting-edge DNA research was halted by her untimely death from cancer in 1958.

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It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi. 

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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#682 2020-02-20 00:56:04

ganesh
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Re: crème de la crème

648) Pehr Victor Edman

Pehr Victor Edman (April 14, 1916 — March 19, 1977) was a Swedish biochemist. He developed a method for sequencing proteins; the Edman degradation.

Early life

Edman was born in Stockholm, Sweden. In 1935 he started studying medicine at Karolinska Institutet, where he became interested in basic research and received a bachelor in medicine in 1938. His research was interrupted by the outbreak of World War II, where he was drafted to serve in the Swedish army. He returned to the Karolinska Institutet where he earned his doctoral degree under advice from Professor Erik Jorpes in 1946.

Developing the Edman Degradation

At the time Edman started working on Angiotensin, it was just being recognized that proteins are distinct entities with a defined molecular mass, electric charge and structure. This inspired Edman to develop a method, that could be used to determine the sequence of amino acids in the protein. In 1947 he was awarded a travel stipend to go to Rockefeller Institute of Medical Research. When he returned to Sweden in 1950 to be an Assistant Professor at the University of Lund, he published his first paper using the method later known as Edman degradation, to determine the sequence of a protein. To his death he continued to work to improve the method to be able to determine longer stretches with smaller amounts of sample.

Late career

In 1957 he moved to Australia to be the director of St. Vincent's School of Medical Research. In 1967 he successfully developed an automated protein sequencer, called the sequenator, with his assistant Geoffrey Begg.

In 1972 he moved to the Max-Planck-Institut of Biochemistry, Martinsried near Munich. He worked with his second wife, Agnes Henschen, and she used Edman's method to sequence fibrinogen.

In 1977 Edman died of a brain tumor after a short coma.

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It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi. 

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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#683 2020-02-22 00:15:58

ganesh
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Re: crème de la crème

649) Mikhail Dolivo-Dobrovolsky


Mikhail Osipovich Dolivo-Dobrovolsky  (2 January [O.S. 21 December 1861] 1862 – 15 November [O.S. 3 November] 1919) was a Polish-Russian engineer, electrician, and inventor.

As one of the founders (the others were Nikola Tesla, Galileo Ferraris and Jonas Wenström) of polyphase electrical systems, he developed the three-phase electrical generator and a three-phase electrical motor (1888) and studied star and delta connections. The triumph of the three-phase system was displayed in Europe at the International Electro-Technical Exhibition of 1891, where Dolivo-Dobrovolsky used this system to transmit electric power at the distance of 176 km with 75% efficiency. In 1891 he also created a three-phase transformer and short-circuited (squirrel-cage) induction motor. He designed the world's first three-phase hydroelectric power plant in 1891.

Life

Mikhail Dolivo-Dobrowolsky was born as the son of the Russian civil servant and landowner of Polish descent Josif Florovich Dolivo-Dobrowolski and Olga Mikhailovna Jewreinova from an old Russian noble family in Gatchina near Saint Petersburg. He spent his school days in Odessa, where his father was transferred in 1872. After secondary school he went to the Riga Polytechnic at the age of 16. At the end of the 1870s, after the murder of Tsar Alexander II, a wave of repression broke out, with which all progressively oriented students were expelled from their university, which was equivalent to a study ban in all of Russia. Among them was Dolivo-Dobrowolsky. After his forced exmatriculation in Riga in 1881, he left his homeland in 1883 and went to Germany.

He studied electrical engineering at the Department of Electrical Engineering and Information Technology of the Technische Hochschule Darmstadt (TH Darmstadt) in Germany from 1883 to 1884. From 1885 to 1887, he became one of Eramus Kittler's first assistants. There he published several smaller publications and was in close contact with Carl Hering, a mechanical engineer from the USA and Kittler's first assistant.

After the inventions, Dolivo-Dobrowolsky continued his research in the field of heavy current technology, inventing the phase meter in 1892 and the ferrodynamic wattmeter in 1909. He published papers and gave numerous lectures. From 1903 to 1907 he devoted himself to scientific work in Lausanne, where he acquired Swiss citizenship with his entire family in 1906.

After his return to Berlin, he continued his work at AEG and became Technical Director of the apparatus factory in 1909. On 24 October 1911, he received an honorary doctorate from the TH Darmstadt, whose Dolivo building bears his name today. During his life he obtained over 60 patents.

In 1919, Dolivo-Dobrowolski died of a severe heart condition at the academic hospital in Heidelberg. He was buried at the forest cemetery of Darmstadt, where his grave (grave site: R 6a 7) - located very close to the memorial of his teacher Erasmus Kittler - can still be visited today. In the city centre of Darmstadt in 1969 a street was named after Dr.-Ing. E. h. Michael Dolivo-Dobrowolsky, the Dolivostraße.

Invention of the three-phase system

In 1887, AEG Director General Emil Rathenau offered him a position, whereupon Dolivo-Dobrowolsky remained associated with the company until the end of his life. At the AEG, Dolivo-Dobrowolsky initially made an effort to further perfect direct current technology. After all, AEG's origins lay in an Edison subsidiary, and Edison, like Siemens, relied entirely on direct current. At that time, alternating current gradually attracted the attention of technicians, and engineers from Ganz Works in Budapest had designed the first transformer in today's sense in 1885. However, AC technology required further equipment, especially reliable and self-starting motors; AC theory was also still underdeveloped. Before Dolivo-Dobrowolsky, the Italian Galileo Ferraris drew attention to alternating current. Ferraris experimented with two alternating currents shifted by 90°, with which he operated specially designed motors. However, he believed that the maximum efficiency was 50 %. Independently of this, in 1887 Nikola Tesla designed a synchronous motor for two-phase alternating current, which was to introduce the two-phase alternating current network in America. Nikola Tesla already dealt with the subject in 1882 and developed a system in a very short time, which was protected by extensive patents. It comprised both motors and generators with multi-phase, preferably two-phase alternating currents.

Regardless of these events, a forward-looking solution was found at AEG in 1888. Dolivo-Dobrowolsky worked with chained three-phase alternating current and introduced the term three-phase current. The associated asynchronous motor invented by him was the first functional solution. However, the asynchronous motor with squirrel-cage rotor had the problem of delivering only low torque at low speeds, such as when starting up. The solution was the slip ring motor, a variation of the asynchronous motor in which the short circuit of the rotor is opened and guided to the outside via sliprings. By connecting various external resistors, Dolivo-Dobrowolsky was able to introduce an asynchronous motor with high starting torque in 1891.

At the beginning of 1889, the first AEG three-phase motors were in operation, and in the following year they already produced 2 to 3 horsepower. Dolivo-Dobrowolsky paid attention to well distributed windings, a low dispersion of the lines of force and as uniform a force field as possible and achieved a satisfactory result. In 1891, he also developed the first Delta-wye transformer for this purpose.

First remote transmission of electrical energy

At AEG and the Swiss cooperation partner Maschinenfabrik Oerlikon (MFO), all components for a three-phase network were available, but until now they had only been in trial operation. At this time, Oskar von Miller made the extremely daring proposal to present the three-phase current transmission system Lauffen-Frankfurt at the International Electrotechnical Exhibition planned for 1891 in Frankfurt at the MFO, where Dolivo-Dobrowolsky and his chief electrician partner Charles E. L. Brown realized the project: A 300 HP three-phase AC generator of the MFO was to be driven by the water turbine of the cement plant in Lauffen am Neckar, generating a voltage of about 50 V and 40 Hz, transforming it up to 15 kV (later 25 kV) and then transmitting it via 175 km of overhead line to Frankfurt and transforming it down again to supply a 100 HP asynchronous motor and several small three-phase motors as well as about 1000 incandescent lamps. The power output of the motors, which had previously been in test operation, was still only 2 to 3 hp. Nevertheless, the plant was put into operation on the evening of 24 August 1891, and a test committee determined that 75 % of the energy generated in Lauffen arrived in Frankfurt. This proved that, on the one hand, alternating current was profitable for a large-scale public electricity supply and, on the other hand, that the three-phase components were now of the same quality as those of direct current technology. The image-boosting effect of the demonstration at the World Expo finally led to the breakthrough of three-phase AC technology. At Siemens and Edison, however, AC technology only slowly gained acceptance, which enabled AEG to become a global company.

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It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi. 

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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#684 2020-02-24 00:56:27

ganesh
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Re: crème de la crème

650) Charles Fabry

Maurice Paul Auguste Charles Fabry (11 June 1867 – 11 December 1945) was a French physicist.

Life

Fabry graduated from the École Polytechnique in Paris and received his doctorate from the University of Paris in 1892, for his work on interference fringes, which established him as an authority in the field of optics and spectroscopy. In 1904, he was appointed Professor of Physics at the University of Marseille, where he spent 16 years.

Career

In optics, he discovered an explanation for the phenomenon of interference fringes. Together with his colleague Alfred Pérot he invented the Fabry–Pérot interferometer in 1899. He and Henri Buisson discovered the ozone layer in 1913.

In 1921, Fabry was appointed Professor of General Physics at the Sorbonne and the first director of the new Institute of Optics. In 1926 he also became professor at the École Polytechnique. He was the first general director of the Institut d'optique théorique et appliquée and director of "grande école" École supérieure d'optique (SupOptique). In 1929, he received the Prix Jules Janssen, the highest award of the Société astronomique de France, the French astronomical society.

Fabry was the President of the Société astronomique de France from 1931-1933.

During his career Fabry published 197 scientific papers, 14 books, and over 100 popular articles. For his important scientific achievements he received the Rumford Medal from the Royal Society of London in 1918. In the United States his work was recognized by the Henry Draper Medal from the National Academy of Sciences (1919) and the Franklin Medal from the Franklin Institute (1921). In 1927 he was elected to the French Academy of Sciences.

(In optics, a Fabry–Pérot interferometer (FPI) or etalon is an optical cavity made from two parallel reflecting surfaces (i.e.: thin mirrors). Optical waves can pass through the optical cavity only when they are in resonance with it. It is named after Charles Fabry and Alfred Perot, who developed the instrument in 1899. Etalon is from the French étalon, meaning "measuring gauge" or "standard".

Etalons are widely used in telecommunications, lasers and spectroscopy to control and measure the wavelengths of light. Recent advances in fabrication technique allow the creation of very precise tunable Fabry–Pérot interferometers. The device is called an interferometer when the distance between the two surfaces (and with it the resonance length) can be changed, and etalon when the distance is fixed (however, the two terms are often used interchangeably)).

Charles_Fabry_pillars.jpg


It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi. 

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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#685 Today 00:17:26

ganesh
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Re: crème de la crème

651) Benoît Fourneyron

Benoît Fourneyron, (born Oct. 31, 1802, Saint-Étienne, Fr.—died July 31, 1867, Paris), French inventor of the water turbine.

The son of a mathematician, he graduated in the first class of the new Saint-Étienne engineering school in 1816. While working in the ironworks at Le Creusot, he studied a proposal advanced by his former professor, Claude Burdin, for a new type of waterwheel that Burdin named a “turbine.” Though neither the Academy of Sciences nor the Society for the Encouragement of Industry accepted Burdin’s paper, Fourneyron recognized its importance and undertook its realization. He built in 1827 a small, six-horsepower unit in which water was directed outward from a central source onto blades or vanes set at angles in a rotor.

By 1837 Fourneyron had produced a turbine capable of 2,300 revolutions per minute, 80 percent efficiency, and 60 horsepower, with a wheel a foot in diameter and weighing only 40 pounds (18 kilograms). Besides its more obvious advantages over the waterwheel, Fourneyron’s turbine could be installed as a horizontal wheel with a vertical shaft. It achieved immediate international success, powering industry in continental Europe and in the United States, notably the New England textile industry. But the real significance of the invention did not emerge until 1895, when Fourneyron turbines were installed on the American side of Niagara Falls to turn generators for electric-power production.

Fourneyron perceived the potential of steam-driven turbines, but his attempts to make a satisfactory steam turbine were thwarted by the inadequacy of available materials and workmanship.

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It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi. 

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