Misplaced Pages

#476523

47-591: IUC may refer to: International Union of Crystallography , founded in 1948 International University College of Turin , a university located in Torino, Italy International University of Chabahar , a university located in Chabahar, Iran Inter-University Center for Japanese Language Studies , a Japanese language school located in Yokohama, Japan IntraUterine Contraceptive ,

94-500: A crystal could be rotated to precise angles while measuring the energy of reflections. This enabled father and son to measure the distances between the atomic sheets in a number of simple crystals. They calculated the spacing of the atoms from the weight of the crystal and the Avogadro constant , which enabled them to measure the wavelengths of the X-rays produced by different metallic targets in

141-513: A crystal in front of a photographic plate; alongside of the spot where the beam struck there were additional spots from deflected rays – hence X-rays are waves. In 1912, as a first-year research student at Cambridge, W. L. Bragg, while strolling by the river, had the insight that crystals made from parallel sheets of atoms would not diffract X-ray beams that struck their surface at most angles because X-rays deflected by collisions with atoms would be out of phase, cancelling one another out. However, when

188-478: A focus for the relations of crystallography to other sciences. The IUCr fulfils these objectives by publishing in print and electronically primary scientific journals through the Acta Crystallographica journal series, as well as Journal of Applied Crystallography , Journal of Synchrotron Radiation , IUCrJ , the series of reference volumes International Tables for Crystallography , distributing

235-646: A guest at the house expressed surprise at seeing him there. He died at a hospital near his home at Waldringfield , Ipswich , Suffolk. He was buried in Trinity College, Cambridge ; his son David is buried in the Parish of the Ascension Burial Ground in Cambridge, where Bragg's friend, who had he survived would have been his brother-in-law, Rudolph Cecil Hopkinson is also buried. In August 2013, Bragg's relative,

282-451: A hormonal contraceptive Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title IUC . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=IUC&oldid=868203401 " Category : Disambiguation pages Hidden categories: Short description

329-451: A hot wire air wave detector that solved the problem. In this work he was aided by Charles Galton Darwin , William Sansome Tucker , Harold Roper Robinson , Edward Andrade and Henry Harold Hemming. British sound ranging was very effective; there was a unit in every British Army and their system was adopted by the Americans when they entered the war. For his work during the war he was awarded

376-541: A long-time family friend, moved to Cambridge, Lawrence Bragg replaced him as Langworthy Professor of Physics at the Victoria University of Manchester . He recruited an excellent faculty, including former sound rangers, but he believed that his knowledge of physics was weak and he had no classroom experience. The students, many veterans, were critical and rowdy. He was deeply shaken but with family support he pulled himself together and prevailed. He and R. W. James measured

423-633: A method to localise enemy artillery from the boom of their firing. On 2 September 1915 his brother was killed during the Gallipoli Campaign . Shortly afterwards, he and his father were awarded the Nobel Prize in Physics. He was 25 years old and remains the youngest science laureate. The problem with sound ranging was that the heavy guns boomed at too low a frequency to be detected by a microphone. After months of frustrating failure he and his group devised

470-454: A thesis. Among Bragg's other interests was shell collecting ; his personal collection amounted to specimens from some 500 species; all personally collected from South Australia. He discovered a new species of cuttlefish – Sepia braggi , named for him by Joseph Verco . The composition of X-rays was unknown, his father argued that X-rays are streams of particles, others argued that they are waves. Max von Laue directed an X-ray beam at

517-671: A year of the termination of fighting in WWII , he arranged for an international meeting of crystallographers in London which was attended by some 120 scientists from most of the allied countries. In that London meeting Ewald was elected Chairman of the Provisional International Crystallographic Committee, which put into action the decision to form the International Union of Crystallography. Sir Lawrence Bragg

SECTION 10

#1733115917477

564-583: Is a Messenger , argued that he was more a crystallographer than a physicist, Bragg's lifelong activity showed otherwise—he was more of a physicist than anything else. Thus, from 1939 to 1943, he served as President of the Institute of Physics , London. In the 1967 New Year Honours he was appointed Member of the Order of the Companions of Honour by Queen Elizabeth II . Since 1967 the Institute of Physics has awarded

611-400: Is denoted by a g . Place holder 1 denotes an orthogonal direction with no reflections. Lawrence Bragg Sir William Lawrence Bragg (31 March 1890 – 1 July 1971), known as Lawrence Bragg , was an Australian-born British physicist and X-ray crystallographer , discoverer (1912) of Bragg's law of X-ray diffraction , which is basic for the determination of crystal structure . He

658-493: Is different from Wikidata All article disambiguation pages All disambiguation pages International Union of Crystallography The objectives of the IUCr are to promote international cooperation in crystallography and to contribute to all aspects of crystallography, to promote international publication of crystallographic research, to facilitate standardization of methods, units, nomenclatures and symbols, and to form

705-458: The 3 10 helix , a conformation that they had proposed earlier. In this conformation, every third peptide is hydrogen-bonded back to the first peptide, thus forming a ring containing ten atoms. They had the complete structure of an enzyme in time for Bragg's 75th birthday. He became Professor Emeritus in 1966. X-ray analysis of protein structure flourished in subsequent years, determining the structures of scores of proteins in laboratories around

752-497: The Laboratory of Molecular Biology , initially consisting of Perutz, John Kendrew and two assistants. Bragg worked with them and by 1960 they had resolved the structure of myoglobin to the atomic level. After this Bragg was less involved; their analysis of haemoglobin was easier after they incorporated two mercury atoms as markers in each molecule. The first monumental triumph of the MRC

799-667: The Lawrence Bragg Medal and Prize . Additionally since 1992, the Australian Institute of Physics has awarded the Bragg Gold Medal for Excellence in Physics to commemorate Lawrence Bragg (in front on the medal) and his father, William Bragg, for the best PhD thesis by a student at an Australian university . The Electoral district of Bragg , in the South Australian House of Assembly , was created in 1970, and

846-631: The Military Cross and appointed Officer of the Order of the British Empire . He was also Mentioned in Despatches on 16 June 1916, 4 January 1917 and 7 July 1919. Hot wire sound ranging was used in World War II during which he served as a civilian adviser. Between the wars, from 1919 to 1937, he worked at the Victoria University of Manchester as Langworthy Professor of Physics. He became

893-479: The Royal Institution he was: In 1921 he married Alice Hopkinson (1899–1989), a cousin of a friend who had been killed in the war. They had four children, the engineer Stephen Lawrence (1923–2014), David William (1926–2005), Margaret Alice (1931–2022) (who married the diplomat Mark Heath ), and Patience Mary (1935–2020). Alice was on the staff at Withington Girls' School until Bragg was appointed director of

940-462: The Wallpaper group with a 4 character name. First it has a P or C for primitive or centered groups. Groups are denoted by a number 1, 2, 3, 4, or 6 for the highest order of symmetry. Groups can have one or two reflections, denoted as vertical mirrors first (horizontal reflection), and horizontal second (vertical reflection). A simple reflection is denoted by an m (mirror), and a glide-reflection

987-513: The 1962 Nobel Prize in Physiology or Medicine; Wilkins' share recognised the contribution of X-ray crystallographers at King's College London . Among them was Rosalind Franklin , whose " photograph 51 " showed that DNA was a double helix , not the triple helix that Linus Pauling had proposed. Franklin died before the prize (which only goes to living people) was awarded. In 1953 the Braggs moved into

SECTION 20

#1733115917477

1034-536: The Discourse on 'Oscillations and noise in jet engines' given by his engineer-son Stephen , who was then Chief Scientist at Rolls-Royce Ltd and later became Vice-Chancellor of Brunel University ." He also introduced a programme of highly regarded Schools' Lectures, enlivened by the elaborate demonstrations that were a hallmark of the Institution. He gave three of these lectures on "electricity". He continued research in

1081-549: The Institution by recruiting a small group to work in the Davy-Faraday Laboratory in the basement and in the adjoining house, supported by grants he obtained. A visitor to the laboratory succeeded in inserting heavy metals into the enzyme lysozyme ; the structure of its crystal was solved in 1965 at the Royal Institution by D. C. Phillips and his coworkers, with the computations on the 9,040 reflections performed on

1128-489: The National Physical Laboratory in 1937. She was active in a number of public bodies and served as Mayor of Cambridge from 1945 to 1946. Bragg's hobbies included drawing – family letters were illustrated with lively sketches – painting, literature and a lifelong interest in gardening. When he moved to London, he missed having a garden and so worked as a part-time gardener, unrecognised by his employer, until

1175-524: The X-ray beam struck at an angle at which the distances it passed between atomic sheets in the crystal equalled the X-ray's wavelength then those deflected would be in phase and produce a spot on a nearby film. From this insight he wrote the simple Bragg equation that relates the wavelength of the X-ray and the distance between atomic sheets in a simple crystal to the angles at which an impinging X-ray beam would be reflected. His father built an apparatus in which

1222-647: The X-ray tubes. W. H. Bragg reported their results at meetings and in a paper, giving credit to "his son" (unnamed) for the equation, but not as a co-author, which gave his son "some heartaches", which he never overcame. Bragg was commissioned early in World War I in the Royal Horse Artillery as a second lieutenant of the Leicestershire battery . In 1915 he was seconded to the Royal Engineers to develop

1269-415: The absolute energy of reflected X-rays, which validated a formula derived by C. G. Darwin before the war. Now they could determine the number of electrons in the reflecting targets, and they were able to decipher the structures of more complicated crystals like silicates. It was still difficult: requiring repeated guessing and retrying. In the late 1920s they eased the analysis by using Fourier transforms on

1316-422: The autumn of 1909 and received a major scholarship in mathematics, despite taking the exam while in bed with pneumonia . After initially excelling in mathematics, he transferred to the physics course in the later years of his studies, and graduated with first class honours in 1911. In 1914 Bragg was elected to a Fellowship at Trinity College – a Fellowship at a Cambridge college involves the submission and defence of

1363-679: The broadcaster Melvyn Bragg , presented a BBC Radio 4 programme ("Bragg on the Braggs") on the 1915 Nobel Prize in Physics winners. Bragg was elected a Fellow of the Royal Society (FRS) in 1921 – "a qualification that makes other ones irrelevant". He was knighted by King George VI in the 1941 New Year Honours, and received both the Copley Medal and the Royal Medal of the Royal Society . Although Graeme Hunter, in his book on Bragg Light

1410-574: The data. In 1930, he became deeply disturbed while weighing a job offer from Imperial College, London. His family rallied around and he recovered his balance while they spent 1931 in Munich, where he did research. He became director of the National Physical Laboratory in Teddington in 1937, bringing some co-workers along. However, administration and committees took much of his time away from

1457-486: The digital computer at the University of London, which greatly facilitated the work. Two of the illustrations of the positioning of amino acids in the chain were drawn by Bragg. Unlike myoglobin, in which nearly 80 per cent of the amino-acid residues are in the alpha-helix conformation, in lysozyme the alpha-helix content is only about 40 per cent of the amino-acid residues found in four main stretches. Other stretches are of

IUC - Misplaced Pages Continue

1504-671: The director of the Cavendish Laboratory , Cambridge, when the discovery of the structure of DNA was reported by James D. Watson and Francis Crick in February 1953. Bragg was born in Adelaide , South Australia to Sir William Henry Bragg (1862–1942), Elder Professor of Mathematics and Physics at the University of Adelaide , and Gwendoline (1869–1929), daughter of Sir Charles Todd , government astronomer of South Australia In 1900, Bragg

1551-485: The director of the National Physical Laboratory in Teddington in 1937. After World War II, Bragg returned to Cambridge, splitting the Cavendish Laboratory into research groups. He believed that "the ideal research unit is one of six to twelve scientists and a few assistants". When demobilised he returned to crystallography at Cambridge. They had agreed that father would study organic crystals, son would investigate inorganic compounds. In 1919 when Ernest Rutherford ,

1598-598: The elegant flat for the Resident Professor in the Royal Institution in London, the position his father had occupied when he died. In 1934 and 1961 Lawrence had delivered the Royal Institution Christmas Lecture and since 1938 he had been Professor of Natural Philosophy in the Institution, delivering an annual lecture. His father's successors had weakened the Institution, so Bragg had to rebuild it. He bolstered finances by enlisting corporate sponsors,

1645-520: The general run of apparatus can be constructed." Senior members of staff now had offices, telephones, and secretarial support. The scope of the department was enlarged with a new unit on radio astronomy. Bragg's own work focused on the structure of metals, using both X-rays and the electron microscope . In 1947 he persuaded the Medical Research Council (MRC) to support what he described as the "gallant attempt" to determine protein structure as

1692-649: The quarterly IUCr Newsletter , maintaining the online World Directory/Database of Crystallographers , awarding the Ewald Prize and organising the triennial Congress and General Assembly. In 1944 the yearly meeting of the X-ray Analysis Group (XRAG) of the UK Institute of Physics was held in Oxford, and the distinguished German crystallographer Paul Peter Ewald , who then taught at Queen's University Belfast ,

1739-639: The traditional Friday Evening Discourses were followed by a dinner party for the speaker and carefully selected possible patrons, more than 120 of them each year. "Two of these Discourses in 1965 gave him particular pleasure. On 7 May, Lady Bragg, who had been a member of the Royal Commission on Marriage and Divorce (1951–55) and was Chairman of the National Marriage Guidance Council , lectured on 'Changing patterns in marriage and divorce'; and on 15 November, Bragg listened with evident pride to

1786-491: The workbench. Rutherford died and the search committee named Lawrence Bragg as next in the line of the Cavendish Professors who direct the Cavendish Laboratory . The Laboratory had an eminent history in atomic physics and some members were wary of a crystallographer, which Bragg surmounted by even-handed administration. He worked on improving the interpretation of diffraction patterns. In the small crystallography group

1833-446: The world. Twenty eight Nobel Prizes have been awarded for work using X-ray analysis. The disadvantage of the method is that it must be done on crystals, which precludes seeing changes in shape when enzymes bind substrates and the like. This problem was solved by the development of another line Bragg had initiated, using modified electron microscopes to image single frozen molecules: cryo-electron microscopy . In his long association with

1880-542: Was a refugee research student without a mentor: Max Perutz . He showed Bragg X-ray diffraction data from haemoglobin , which suggested that the structure of giant biological molecules might be deciphered. Bragg appointed Perutz as his research assistant and within a few months obtained additional support with a grant from the Rockefeller Foundation . The work was suspended during the Second World War when Perutz

1927-459: Was a student at Queen's School, North Adelaide , followed by five years at St Peter's College, Adelaide . He went to the University of Adelaide at the age of 16 to study mathematics, chemistry and physics, graduating in 1908. In the same year his father accepted the Cavendish chair of physics at the University of Leeds , and brought the family to England. Bragg entered Trinity College, Cambridge in

IUC - Misplaced Pages Continue

1974-619: Was decoding the structure of DNA by James Watson and Francis Crick . Bragg announced the discovery at a Solvay conference on proteins in Belgium on 8 April 1953, though it went unreported by the press. He then gave a talk at Guy's Hospital Medical School in London on Thursday, 14 May 1953, which resulted in an article by Ritchie Calder in the News Chronicle of London on Friday, 15 May 1953, entitled "Why You Are You. Nearer Secret of Life". Bragg nominated Crick, Watson and Maurice Wilkins for

2021-585: Was interned as an enemy alien and then worked in military research. During the war the Cavendish offered a shortened graduate course which emphasised the electronics needed for radar . Bragg worked on the structure of metals and consulted on sonar and sound ranging, for which the Tucker microphone was still used. Bragg was knighted and became Sir Lawrence in 1941. After his father died in 1942, Bragg served for six months as Scientific Liaison Officer to Canada. He also organised periodic conferences on X-ray analysis, which

2068-537: Was invited to give the evening lecture. In it he gave a historical survey of some of the stages in the evolution of X-ray crystallography and ended with a strong plea for the formation of an international society or union which would represent, and unify publication for, the new science. This idea was followed up by the British crystallographers, and particularly by Sir Lawrence Bragg , the Chairman of XRAG. In June 1946, within

2115-401: Was joint recipient (with his father, William Henry Bragg ) of the Nobel Prize in Physics in 1915, "For their services in the analysis of crystal structure by means of X-rays "; an important step in the development of X-ray crystallography. Bragg was knighted in 1941. As of 2024, he is the youngest ever Nobel laureate in physics, having received the award at the age of 25. Bragg was

2162-410: Was the first formally elected President of the IUCr, with Ralph Walter Graystone Wyckoff and Arne Westgren as Vice-Presidents. Ewald was elected as 5th President of the IUCr, the 'international society or union' that he had originally conceived, in 1960. The IUCr notation is the notation for the symmetry group adopted by the International Union of Crystallography in 1952. It identifies members of

2209-460: Was widely used in military research . After the war Bragg led in the formation of the International Union of Crystallography and was elected its first president. He reorganised the Cavendish into units to reflect his conviction that "the ideal research unit is one of six to twelve scientists and a few assistants, helped by one or more first-class instrument mechanics and a workshop in which

#476523