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= = = Alloys = = =
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Antimony forms a highly useful alloy with lead , increasing its hardness and mechanical strength . For most applications involving lead , varying amounts of antimony are used as alloying metal . In lead – acid batteries , this addition improves the charging characteristics and reduces generation of unwanted hydrogen d... |
= = = Other applications = = =
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Three other applications make up nearly all the rest of the consumption . One of these uses is as a stabilizer and a catalyst for the production of polyethyleneterephthalate . Another application is to serve as a fining agent to remove microscopic bubbles in glass , mostly for TV screens ; this is achieved by the inte... |
Antimony is being increasingly used in the semiconductor industry as a dopant for heavily doped n @-@ type silicon wafers in the production of diodes , infrared detectors , and Hall @-@ effect devices . In the 1950s , tiny beads of a lead @-@ antimony alloy were used to dope the emitters and collectors of n @-@ p @-@ ... |
Few biological or medical applications exist for antimony . Treatments principally containing antimony are known as antimonials and are used as emetics . Antimony compounds are used as antiprotozoan drugs . Potassium antimonyl tartrate , or tartar emetic , was once used as an anti @-@ schistosomal drug from 1919 on . ... |
Antimony @-@ based drugs , such as meglumine antimoniate , are also considered the drugs of choice for treatment of leishmaniasis in domestic animals . Unfortunately , as well as having low therapeutic indices , the drugs are poor at penetrating the bone marrow , where some of the Leishmania amastigotes reside , and s... |
In the heads of some safety matches , antimony ( III ) sulfide is used . Antimony @-@ 124 is used together with beryllium in neutron sources ; the gamma rays emitted by antimony @-@ 124 initiate the photodisintegration of beryllium . The emitted neutrons have an average energy of 24 keV . Antimony sulfides have been s... |
Antimony also is used in the making of bullets and bullet tracers . This element is also used in paint and glass art crafts and as opacifier in enamel .
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= = Precautions = =
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The effects of antimony and its compounds on human and environmental health differ widely . The massive antimony metal does not affect human and environmental health . Inhalation of antimony trioxide ( and similar poorly soluble Sb ( III ) dust particles such as antimony dust ) is considered harmful and suspected of c... |
For oral absorption , ICRP ( 1994 ) recommended values of 10 % for tartar emetic and 1 % for all other antimony compounds . Dermal absorption for metals is estimated at most 1 % ( HERAG , 2007 ) . Inhalation absorption of antimony trioxide and other poorly soluble Sb ( III ) substances ( such as antimony dust ) is est... |
Antimony is mainly excreted from the human body via urine . Antimony and its compounds do not cause acute human health effects , with the exception of antimony potassium tartrate ( " tartar emetic " ) , a prodrug that is intentionally used to treat leishmaniasis patients .
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Prolonged skin contact with antimony dust may cause dermatitis . However , it was agreed at the European Union level that the skin rashes observed are not substance @-@ specific , but most probably due to a physical blocking of sweat ducts ( ECHA / PR / 09 / 09 , Helsinki , 6 July 2009 ) . Antimony dust may also be ex... |
Antimony is incompatible with strong acids , halogenated acids , and oxidizers ; when exposed to newly formed hydrogen it may form stibine ( SbH3 ) .
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The 8 hour time weighted average ( TWA ) is set at 0 @.@ 5 mg / m3 by the American Conference of Governmental Industrial Hygienists and by the Occupational Safety and Health Administration ( OSHA ) as a legal permissible exposure limit ( PEL ) in the workplace . The National Institute for Occupational Safety and Healt... |
World Health Organization : 20 µg / L
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Japan : 15 µg / L
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United States Environmental Protection Agency , Health Canada and the Ontario Ministry of Environment : 6 µg / L
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EU and German Federal Ministry of Environment : 5 µg / L
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The TDI proposed by WHO is 6 µg antimony per kilogram of body weight . The IDLH ( immediately dangerous to life and health ) value for antimony is 50 mg / m3 .
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= Mortimer Wheeler =
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Sir Robert Eric Mortimer Wheeler CH , CIE , MC , TD , FSA , FRS , FBA ( 10 September 1890 – 22 July 1976 ) was a British archaeologist and officer in the British Army . Over the course of his career , he served as Director of both the National Museum of Wales and London Museum , Director @-@ General of the Archaeologi... |
Born in Glasgow to a middle @-@ class family , Wheeler was raised largely in Yorkshire before relocating to London in his teenage years . After studying Classics at University College London ( UCL ) , he began working professionally in archaeology , specializing in the Romano @-@ British period . During World War I he... |
In 1934 , he established the Institute of Archaeology as part of the federal University of London , adopting the position of Honorary Director . In this period , he oversaw excavations of the Roman sites at Lydney Park and Verulamium and the Iron Age hill fort of Maidan Castle . During World War II , he re @-@ joined ... |
Wheeler is recognised as one of the most important British archaeologists of the twentieth century , responsible for successfully encouraging British public interest in the discipline and advancing methodologies of excavation and recording . Further , he is widely acclaimed as a major figure in the establishment of So... |
= = Early life = =
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= = = Childhood : 1890 – 1907 = = =
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Mortimer Wheeler was born on 10 September 1890 in the city of Glasgow , Scotland . He was the first child of the journalist Robert Mortimer Wheeler and his second wife Emily Wheeler ( née Baynes ) . The son of a tea merchant based in Bristol , in youth Robert had considered becoming a Baptist minister , but instead be... |
When Wheeler was four , his father was appointed chief leader writer for the Bradford Observer . The family relocated to Saltaire , a village northwest of Bradford , a cosmopolitan city in Yorkshire , northeast England , which was then in the midst of the wool trade boom . Wheeler was inspired by the moors surrounding... |
In 1899 , Wheeler joined Bradford Grammar School shortly before his ninth birthday , where he proceeded straight to the second form . In 1902 Robert and Emily had a second daughter , whom they named Betty ; Mortimer showed little interest in this younger sister . In 1905 , Robert agreed to take over as head of the Lon... |
= = = University and early career : 1907 – 14 = = =
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After passing the entrance exam on his second attempt , in 1907 Wheeler was awarded a scholarship to read classical studies at University College London ( UCL ) , commuting daily from his parental home to the university campus in Bloomsbury , central London . At UCL , he was taught by the prominent classicist A. E. Ho... |
Wheeler began studying for a Master of Arts degree in classical studies , which he attained in 1912 . During this period , he also gained employment as the personal secretary of the UCL Provost Gregory Foster , although he later criticised Foster for transforming the university from " a college in the truly academic s... |
During his studies , Wheeler had developed his love of archaeology , having joined an excavation of Viroconium Cornoviorum , a Romano @-@ British settlement in Wroxeter , in 1913 . Considering a profession in the discipline , he won a studentship that had been established jointly by the University of London and the So... |
At this period , there were very few jobs available within British archaeology ; as the later archaeologist Stuart Piggott related , " the young Wheeler was looking for a professional job where the profession had yet to be created . " In 1913 Wheeler secured a position as junior investigator for the English Royal Comm... |
= = = First World War : 1914 – 18 = = =
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After the United Kingdom 's entry into World War I in 1914 , Wheeler volunteered for the armed forces . Although preferring solitary to group activities , Wheeler found that he greatly enjoyed soldiering . For the next seven months , he was posted as an instructor in the University of London Officer Training Corps . I... |
In October 1917 Wheeler was posted to the 76th Army Field Artillery Brigade , one of the Royal Field Artillery brigades under the direct control of the General Officer Commanding , Third Army . The brigade was then stationed in Belgium , where it had been engaged in the Battle of Passchendaele against German troops al... |
Wheeler and the brigade arrived in Italy on 20 November , and proceeded through the Italian Riviera to reach Caporetto , where it had been sent to bolster the Italian troops against a German and Austro @-@ Hungarian advance . As the Russian Republic removed itself from the war , the German Army refocused its efforts o... |
= = Career = =
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= = = National Museum of Wales : 1919 – 26 = = =
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On returning to London , Wheeler moved into a top @-@ floor flat near Gordon Square with his wife and child . He returned to working for the Royal Commission , examining and cataloguing the historic structures of Essex . In doing so , he produced his first publication , an academic paper on Colchester 's Roman Balkern... |
He obtained a post as the Keeper of Archaeology at the National Museum of Wales , a job that also entailed becoming a lecturer in archaeology at the University College of South Wales and Monmouthshire . Taking up this position , he moved to Cardiff with his family in August 1920 , although he initially disliked the ci... |
Wheeler was impatient to start excavations , and in July 1921 started a six @-@ week project to excavate at the Roman fort of Segontium ; accompanied by his wife , he used up his holiday to oversee the project . A second season of excavation at the site followed in 1922 . Greatly influenced by the writings of the arch... |
Over the field seasons of 1924 and 1925 , Wheeler ran excavations of the Roman fort of Y Gaer near Brecon , a project aided by his wife and two archaeological students , Nowell Myres and Christopher Hawkes . During this project , he was visited by the prominent Egyptologist Sir Flinders Petrie and his wife Hilda Petri... |
In 1924 , the Director of the National Museum of Wales , William Evans Hoyle , resigned amid ill health . Wheeler applied to take on the role of his replacement , providing supportive testimonials from Charles Reed Peers , Robert Bosanquet , and H. J. Fleure . Although he had no prior museum experience , he was succes... |
= = = London Museum : 1926 – 33 = = =
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Upon the retirement of the Keeper of the London Museum , Harmon Oates , Wheeler was invited to fill the vacancy . He had been considering a return to London for some time and eagerly agreed , taking on the post , which was based at Lancaster House in the St James 's area , in July 1926 . In Wales , many felt that Whee... |
Tessa 's biographer L.C. Carr later commented that together , the Wheelers " professionalized the London Museum " . Wheeler expressed his opinion that the museum " had to be cleaned , expurgated , and catalogued ; in general , turned from a junk shop into a tolerably rational institution " . Focusing on reorganising t... |
Soon after joining the museum , Wheeler was elected to the council of the Society of Antiquaries . Through the Society , he became involved in the debate as to who should finance archaeological supervision of building projects in Greater London ; his argument was that the City of London Corporation should provide the ... |
Wheeler was keen to continue archaeological fieldwork outside London , undertaking excavations every year from 1926 to 1939 . After completing his excavation of the Carlaeon amphitheatre in 1928 , he began fieldwork at the Roman settlement and temple in Lydney Park , Gloucestershire , having been invited to do so by t... |
From there , Wheeler was invited to direct a Society of Antiquaries excavation at the Roman settlement of Verulamium , which existed on land recently acquired by the Corporation of St Albans . He took on this role for four seasons from 1930 to 1933 , before leaving a fifth season of excavation under the control of the... |
= = = Institute of Archaeology : 1934 – 39 = = =
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Wheeler had long desired to establish an academic institution devoted to archaeology that could be based in London . He hoped that it could become a centre in which to establish the professionalisation of archaeology as a discipline , with systematic training of students in methodological techniques of excavation and ... |
After ending his work at Verulamium , Wheeler turned his attention to the late Iron Age hill @-@ fort of Maidan Castle near to Dorchester , Dorset , where he excavated for four seasons from 1934 to 1937 . Co @-@ directed by Wheeler , Tessa , and the Curator of Dorset County Museum , Charles Drew , the project was carr... |
In 1936 , Wheeler embarked on a visit to the Near East , sailing from Marseilles to Port Said , where he visited the Old Kingdom tombs of Sakkara . From there he went via Sinai to Palestine , Lebanon , and Syria . During this trip , he visited various archaeological projects , but was dismayed by the quality of their ... |
After a search that had taken several years , Wheeler was able to secure a premises for the Institute of Archaeology : St. John 's Lodge in Regent 's Park , central London . Left empty since its use as a hospital during the First World War , the building was owned by the Crown and was controlled by the First Commissio... |
Wheeler had also become President of the Museums Association , and in a presidential address given in Belfast talked on the topic of preserving museum collections in war time , believing that Britain 's involvement in a second European conflict was imminent . In anticipation of this event , in August 1939 he arranged ... |
After Maidan Castle , Wheeler turned his attention to France , where the archaeological investigation of Iron Age sites had lagged behind developments in Britain . There , he oversaw a series of surveys and excavations with the aid of Leslie Scott , beginning with a survey tour of Brittany in the winter of 1936 – 37 .... |
= = = Second World War : 1939 – 45 = = =
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Wheeler had been expecting and openly hoping for war with Nazi Germany for a year prior to the outbreak of hostilities ; he believed that the United Kingdom 's involvement in the conflict would remedy the shame that he thought had been brought upon the country by its signing of the Munich Agreement in September 1938 .... |
In the summer of 1941 , Wheeler and three of his batteries were assigned to fight against German and Italian forces in the North African Campaign . In September , they set sail from Glasgow aboard the RMS Empress of Russia ; because the Mediterranean was controlled largely by enemy naval forces , they were forced to t... |
Serving with the Eighth Army , Wheeler was present in North Africa when the Axis armies pushed the Allies back to El Alamein . He was also part of the Allied counter @-@ push , taking part in the Second Battle of El Alamein and the advance on Axis @-@ held Tripoli . On the way he became concerned that the archaeologic... |
Promoted to the rank of brigadier , after the German surrender in North Africa , Wheeler was sent to Algiers where he was part of the staff committee planning the invasion of Italy . There , he learned that the India Office had requested that the army relieve him of his duties to permit him to be appointed Director Ge... |
Wheeler left Italy in November 1943 and returned to London . There , he resigned as the director of the London Museum and focused on organising the Institute of Archaeology , preparing it for its adoption of a new director , V. Gordon Childe , after the war . He also resigned as director of the Society of Antiquaries ... |
= = = Archaeological Survey of India : 1944 – 48 = = =
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Wheeler arrived in Bombay in the spring of 1944 . There , he was welcomed by the city 's governor , John Colville , before heading by train to Delhi and then Simla , where the headquarters of the Archaeological Survey of India were located . Wheeler had been suggested for the job by Archibald Wavell , the Viceroy of I... |
From the beginning of his tenure , he sought to distance himself from previous Director @-@ Generals and their administrations by criticising them in print and attempting to introduce new staff who had no loyalty to his predecessors . Assigned with a four @-@ year contract , Wheeler attempted to recruit two archaeolog... |
In October 1944 , he opened his six @-@ month archaeological field school in Taxila , where he instructed various students from across India in the methodologies of the discipline . Wheeler became very fond of his students , with one of them , B. B. Lal , later commenting that " behind the gruff exterior , Sir Mortime... |
Turning his attention to southern India , Wheeler discovered remnants of a Roman amphora in a museum , and began excavations at Arikamedu , revealing a port from the first century CE which had traded in goods from the Roman Empire . The excavation had been plagued by severe rains and tropical heat , although it was du... |
Wheeler established a new archaeological journal , Ancient India , planning for it to be published twice a year . He had trouble securing printing paper and faced various delays ; the first issue was released in January 1946 , and he would release three further volumes during his stay . Wheeler married Kim Collingridg... |
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