Margaret O'Brien is an American film, radio and stage actress. Beginning a prolific career as a child actress in feature films for Metro-Goldwyn-Mayer at the age of four, O'Brien became one of the most popular child stars in cinema history and was honored with a Juvenile Academy Award as the outstanding child actress of 1944. In her career, she appeared on television, on stage, in supporting film roles. Margaret O'Brien was born Angela Maxine O'Brien, her father, Lawrence O'Brien, a circus performer, died. O'Brien's mother, Gladys Flores, was a well-known flamenco dancer who performed with her sister Marissa a dancer. O'Brien is of half-Spanish ancestry, she was raised Catholic. O'Brien made her first film appearance in Metro-Goldwyn-Mayer's Babes on Broadway at the age of four, but it was the following year that her first major role brought her widespread attention; as a five-year-old in Journey for Margaret, O'Brien won wide praise for her quite convincing acting style, unusual for a child of her age.
By 1943, she was considered a big enough star to have a cameo appearance in the all-star military show finale of Thousands Cheer. In 1943, at the age of seven, Margaret co-starred in "You, John Jones," a "War Bond/Effort," short film, with James Cagney and Ann Sothern, in which she recited President Lincoln's "Gettysburg Address." She played Adèle, a young French girl, spoke and sang all her dialogue with a French accent in Jane Eyre. Arguably her most memorable role was opposite Judy Garland; as Tootie Smith, the feisty but fragile little sister of Judy Garland, she was a bright point in a good film in her musical numbers with Garland and during a Halloween sequence in which she confronts a grouchy neighbor. For her performance, she was awarded a special juvenile Oscar in 1944. Margaret and June Allyson were known as "The Town Criers" of MGM. "We were always in competition: I wanted to cry better than June, June wanted to cry better than me. The way my mother got me to cry was if I was having trouble with a scene, she'd say,'why don't we have the make-up man come over and give you false tears?'
I'd think to myself,'they'll say I'm not as good as June,' and I'd start to cry." Her other successes included The Canterville Ghost, Our Vines Have Tender Grapes, Bad Bascomb with Wallace Beery, the first sound version of The Secret Garden. She played Beth in the 1949 MGM release of Little Women, but she was unable to make the transition to adult roles. O'Brien shed her child star image in 1958 by appearing on the cover of Life magazine with the caption "The Girl's Grown", was a mystery guest on the TV panel show What's My Line?. O'Brien's acting appearances as an adult have been sporadic in small independent films and occasional television roles, she has given interviews for the Turner Classic Movies cable network. O'Brien gave television credit for helping her to change her public image. In an interview in 1957, when she was 20, she said: "The wonderful thing about TV is that it has given me a chance to get out of the awkward age -- something the movies couldn't do for me. No movie producer could afford to take a chance at handing me an adult role."On December 22, 1957, O'Brien starred in "The Young Years" on General Electric Theater.
She played the role of Betsy Stauffer, a small-town nurse, in "The Incident of the Town in Terror" on television's Rawhide. She made a guest appearance on a 1963 episode of Perry Mason as Virginia Trent in "The Case of the Shoplifter's Shoe." In 1967, she made a guest appearance on the World War II TV drama Combat!. In a 1968 two-part episode of Ironside, ("Split Second to an Epitaph," O'Brien played a pharmacist, involved in drug theft and was accessory to attempted murder of star Raymond Burr's Ironside. Another rare television outing was as a guest star on the popular Marcus Welby, M. D. in the early 1970s, reuniting O'Brien with her Journey For Margaret and The Canterville Ghost co-star Robert Young. In 1991, O'Brien appeared in Murder, She Wrote, season 7, episode "Who Killed J. B. Fletcher?". While O'Brien was growing up, her awards were always kept in a special room. One day in 1954, the family's maid asked to take O'Brien's Juvenile Oscar and two other awards home with her to polish, as she had done in the past.
After three days, the maid failed to return to work, prompting O'Brien's mother to discharge her, requesting that the awards be returned. Not long after, O'Brien's mother, sick with a heart condition, suffered a relapse and died. In mourning, 17-year-old O'Brien forgot about the maid and the Oscar until several months when she tried to contact her, only to find that the maid had moved and had left no forwarding address. Several years upon learning that the original had been stolen, the Academy promptly supplied O'Brien with a replacement Oscar, but O'Brien still held on to hope that she might one day recover her original Award. In the years that followed, O'Brien attended memorabilia shows and searched antique shops, hoping she might find the original statuette, until one day in 1995 when Bruce Davis executive director of the Academy, was alerted that a miniature statuette bearing O'Brien's name had surfaced in a catalogue for an upcoming memorabilia auction. Davis contacted a mutual friend of his and O'Brien's, who in turn phoned O'Brien to tell her the long-lost Oscar had been found.
Memorabilia collectors Steve N
Robert Walker (actor, born 1918)
Robert Hudson Walker was an American actor, best remembered for his starring role in Alfred Hitchcock's thriller Strangers on a Train, released shortly before his death. He started in youthful boy-next-door roles as a World War II soldier. One of these roles was opposite Jennifer Jones, in the war epic Since You Went Away, he played Jerome Kern in Till the Clouds Roll By. Twice divorced by 30, he suffered from alcoholism and mental illness, which were exacerbated by his painful separation and divorce from Jones. Walker was born the youngest in the family of four boys in Utah. Scarred by his parents' divorce when he was still a child, he subsequently developed an interest in acting, which led his maternal aunt, Hortense McQuarrie Odlum, to offer to pay for his enrollment at the American Academy of Dramatic Arts in New York City in 1937. Walker lived in her home during his first year in the city. While attending the American Academy of Dramatic Arts, Walker met fellow aspiring actress Phylis Isley, who took the stage name Jennifer Jones.
After a brief courtship, the couple married in Tulsa, Oklahoma, on January 2, 1939. Walker had some small unbilled parts in films like Winter Carnival, two Lana Turner films at MGM These Glamour Girls and Dancing Co-Ed. Walker found work in radio while Phylis stayed home and gave birth to two sons in quick succession - actor Robert Walker Jr. and Michael Walker. Walker co-starred in the weekly show Maudie's Diary from August 1941 to September 1942. Phylis returned to auditioning where her luck changed when she was discovered in 1941 by producer David O. Selznick, who changed her name to Jennifer Jones and groomed her for stardom; the couple returned to Hollywood, Selznick's connections helped Walker secure a contract with Metro-Goldwyn-Mayer, where he started work on the war drama Bataan, playing a soldier who fights in the Bataan retreat. He followed it with a supporting role in Madame Curie. Both were notable commercial successes. Walker's charming demeanor and boyish good looks caught on with audiences, he was promoted to stardom with the title part in as the "boy-next-door" soldier in See Here, Private Hargrove.
He appeared in Selznick's Since You Went Away in which he and his wife portrayed doomed young lovers during World War II. By that time, Jones' affair with Selznick was common knowledge, Jones and Walker separated in November 1943, in mid-production; the filming of their love scenes was torturous as Selznick insisted that Walker perform take after take of each love scene with Jones. She filed for divorce in April 1945. Since You Went Away was one of the most financially successful movies of 1944, earning over $7 million. Back at MGM, Walker appeared alongside Spencer Tracy and Van Johnson in Thirty Seconds Over Tokyo, the story of the Doolittle Raid, he played flight engineer and turret gunner David Thatcher, it was another box office hit. Walker starred as a GI preparing for overseas deployment in The Clock, with Judy Garland playing his love interest in her first straight dramatic film, it was profitable. He made a romantic comedy with Hedy Lamarr and June Allyson, Her Highness and the Bellboy.
He did a second Hargrove film, What Next, Corporal Hargrove? and a romantic comedy with June Allyson, The Sailor Takes a Wife. Walker starred in the musical Till the Clouds Roll By, in which he played the popular composer Jerome Kern, which had rental receipts of over $6 million.. He starred as another composer, Johannes Brahms, in Song of Love, which co-starred Katharine Hepburn and Paul Henreid, which lost MGM over a $1 million. In between, he made a film about the construction of the atomic bomb, The Beginning or the End, which resulted in a loss at the box-office, a Tracy-Hepburn drama directed by Elia Kazan, The Sea of Grass, profitable. In 1948, Walker was borrowed by Universal to star with Ava Gardner in the film One Touch of Venus, directed by William A. Seiter; the film was a non-musical comedy adapted from a Broadway show with music by Kurt Weill. He married Barbara Ford, the daughter of director John Ford, in July 1948, but the marriage lasted only five months. Back at MGM he was in some films which lost money, Please Believe Me with Deborah Kerr and The Skipper Surprised His Wife with Joan Leslie.
More popular was a Western with Burt Lancaster, Vengeance Valley, a notable hit. Walker spent time at the Menninger Clinic in 1949. Following his discharge, he was cast by director Alfred Hitchcock in Strangers on a Train. In his final film, Walker played the title role of Leo McCarey's My Son John, made at the height of the Red Scare. Despite the film's anti-Communist themes, Walker was neither liberal nor conservative and took the job to work with McCarey and co-star Helen Hayes. Walker died before production finished, so angles from his death scene in Strangers were spliced into a similar melodramatic death scene near the end of the film. On the night of August 28, 1951, Walker's housekeeper reputedly found Walker in an emotional state, she called the actor's psychiatrist who administered amobarbital for sedation. Walker had been drinking before the outburst, it is believed the combination of amobarbital and alcohol caused him to lose consciousness and stop breathing. Efforts to resuscitate Walker failed.
The loss of such a promising young Hollywood actor was lamented. In her biography of Walker and Jones, Star-Crossed, author B
Uraninite pitchblende, is a radioactive, uranium-rich mineral and ore with a chemical composition, UO2, but due to oxidation the mineral contains variable proportions of U3O8. Additionally, due to radioactive decay, the ore contains oxides of lead and trace amounts of helium, it may contain thorium and rare earth elements. Uraninite used to be known as pitchblende (from pitch, because of its black color, blende, a term used by German miners to denote minerals whose density suggested metal content, but whose exploitation, at the time they were named, was either unknown or not economically feasible; the mineral has been known at least since the 15th century from silver mines in the Ore Mountains, on the German/Czech border. The type locality is the historic mining and spa town known as Joachimsthal, the modern day Jáchymov, on the Czech side of the mountains, where F. E. Brückmann described the mineral in 1772. Pitchblende from the Johanngeorgenstadt deposit in Germany was used by M. Klaproth in 1789 to discover the element uranium.
All uraninite minerals contain a small amount of radium as a radioactive decay product of uranium. Marie Curie used pitchblende, processing tons of it herself, as the source material for her isolation of radium in 1898. Uraninite always contains small amounts of the lead isotopes 206Pb and 207Pb, the end products of the decay series of the uranium isotopes 238U and 235U respectively. Small amounts of helium are present in uraninite as a result of alpha decay. Helium was first found on Earth in uraninite after having been discovered spectroscopically in the Sun's atmosphere; the rare elements technetium and promethium can be found in uraninite in small quantities, produced by the spontaneous fission of uranium-238. Francium can be found in uraninite at 1 francium atom for every 1 × 1018 uranium atoms in the ore as a result from the decay of actinium. Uraninite is a major ore of uranium; some of the highest grade uranium ores in the world were found in the Shinkolobwe mine in the Democratic Republic of the Congo and in the Athabasca Basin in northern Saskatchewan, Canada.
Another important source of pitchblende is at Great Bear Lake in the Northwest Territories of Canada, where it is found in large quantities associated with silver. It occurs in Australia, the Czech Republic, England, Rwanda and South Africa. In the United States, it can be found in the states of Arizona, Connecticut, New Hampshire, New Mexico, North Carolina and Wyoming; the geologist Charles Steen made a fortune on the production of uraninite in his Mi Vida mine in Moab, Utah. Uranium ore is processed close to the mine into yellowcake, an intermediate step in the processing of uranium. Thorianite Uranium ore deposits List of minerals List of uranium mines
An ore is an occurrence of rock or sediment that contains sufficient minerals with economically important elements metals, that can be economically extracted from the deposit. The ores are extracted from the earth through mining; the ore grade, or concentration of an ore mineral or metal, as well as its form of occurrence, will directly affect the costs associated with mining the ore. The cost of extraction must thus be weighed against the metal value contained in the rock to determine what ore can be processed and what ore is of too low a grade to be worth mining. Metal ores are oxides, silicates, or native metals that are not concentrated in the Earth's crust, or noble metals such as gold; the ores must be processed to extract the elements of interest from the waste rock and from the ore minerals. Ore bodies are formed by a variety of geological processes; the process of ore formation is called ore genesis. An ore deposit is an accumulation of ore; this is distinct from a mineral resource. An ore deposit is one occurrence of a particular ore type.
Most ore deposits are named according to their location, or after a discoverer, or after some whimsy, a historical figure, a prominent person, something from mythology or the code name of the resource company which found it. Ore deposits are classified according to various criteria developed via the study of economic geology, or ore genesis; the classifications below are typical. Mesothermal lode gold deposits, typified by the Golden Mile, Kalgoorlie Archaean conglomerate hosted gold-uranium deposits, typified by Elliot Lake, Ontario and Witwatersrand, South Africa Carlin–type gold deposits, including. Volcanic hosted massive sulfide Cu-Pb-Zn including. Stratiform arkose-hosted and shale-hosted copper, typified by the Zambian copperbelt. Stratiform tungsten, typified by the Erzgebirge deposits, Czechoslovakia Exhalative spilite-chert hosted gold deposits Mississippi valley type zinc-lead deposits Hematite iron ore deposits of altered banded iron formation Sudbury Basin nickel and copper, Canada The basic extraction of ore deposits follows these steps: Prospecting or exploration to find and define the extent and value of ore where it is located Conduct resource estimation to mathematically estimate the size and grade of the deposit Conduct a pre-feasibility study to determine the theoretical economics of the ore deposit.
This identifies, early on, whether further investment in estimation and engineering studies is warranted and identifies key risks and areas for further work. Conduct a feasibility study to evaluate the financial viability and financial risks and robustness of the project and make a decision as whether to develop or walk away from a proposed mine project; this includes mine planning to evaluate the economically recoverable portion of the deposit, the metallurgy and ore recoverability and payability of the ore concentrates, engineering and infrastructure costs and equity requirements and a cradle to grave analysis of the possible mine, from the initial excavation all the way through to reclamation. Development to create access to an ore body and building of mine plant and equipment The operation of the mine in an active sense Reclamation to make land where a mine had been suitable for future use Ores are traded internationally and comprise a sizeable portion of international trade in raw materials both in value and volume.
This is because the worldwide distribution of ores is unequal and dislocated from locations of peak demand and from smelting infrastructure. Most base metals are traded internationally on the London Metal Exchange, with
Crystallization is the process by which a solid forms, where the atoms or molecules are organized into a structure known as a crystal. Some of the ways by which crystals form are precipitating from a solution, freezing, or more deposition directly from a gas. Attributes of the resulting crystal depend on factors such as temperature, air pressure, in the case of liquid crystals, time of fluid evaporation. Crystallization occurs in two major steps; the first is nucleation, the appearance of a crystalline phase from either a supercooled liquid or a supersaturated solvent. The second step is known as crystal growth, the increase in the size of particles and leads to a crystal state. An important feature of this step is that loose particles form layers at the crystal's surface lodge themselves into open inconsistencies such as pores, etc; the majority of minerals and organic molecules crystallize and the resulting crystals are of good quality, i.e. without visible defects. However, larger biochemical particles, like proteins, are difficult to crystallize.
The ease with which molecules will crystallize depends on the intensity of either atomic forces, intermolecular forces or intramolecular forces. Crystallization is a chemical solid–liquid separation technique, in which mass transfer of a solute from the liquid solution to a pure solid crystalline phase occurs. In chemical engineering, crystallization occurs in a crystallizer. Crystallization is therefore related to precipitation, although the result is not amorphous or disordered, but a crystal; the crystallization process consists of two major events and crystal growth which are driven by thermodynamic properties as well as chemical properties. In crystallization Nucleation is the step where the solute molecules or atoms dispersed in the solvent start to gather into clusters, on the microscopic scale, that become stable under the current operating conditions; these stable clusters constitute the nuclei. Therefore, the clusters need to reach a critical size; such critical size is dictated by many different factors.
It is at the stage of nucleation that the atoms or molecules arrange in a defined and periodic manner that defines the crystal structure — note that "crystal structure" is a special term that refers to the relative arrangement of the atoms or molecules, not the macroscopic properties of the crystal, although those are a result of the internal crystal structure. The crystal growth is the subsequent size increase of the nuclei that succeed in achieving the critical cluster size. Crystal growth is a dynamic process occurring in equilibrium where solute molecules or atoms precipitate out of solution, dissolve back into solution. Supersaturation is one of the driving forces of crystallization, as the solubility of a species is an equilibrium process quantified by Ksp. Depending upon the conditions, either nucleation or growth may be predominant over the other, dictating crystal size. Many compounds have the ability to crystallize with some having different crystal structures, a phenomenon called polymorphism.
Each polymorph is in fact a different thermodynamic solid state and crystal polymorphs of the same compound exhibit different physical properties, such as dissolution rate, melting point, etc. For this reason, polymorphism is of major importance in industrial manufacture of crystalline products. Additionally, crystal phases can sometimes be interconverted by varying factors such as temperature. There are many examples of natural process. Geological time scale process examples include: Natural crystal formation. Human time scale process examples include: Snow flakes formation. Crystal formation can be divided into two types, where the first type of crystals are composed of a cation and anion known as a salt, such as sodium acetate; the second type of crystals are composed for example menthol. Crystal formation can be achieved by various methods, such as: cooling, addition of a second solvent to reduce the solubility of the solute, solvent layering, changing the cation or anion, as well as other methods.
The formation of a supersaturated solution does not guarantee crystal formation, a seed crystal or scratching the glass is required to form nucleation sites. A typical laboratory technique for crystal formation is to dissolve the solid in a solution in which it is soluble at high temperatures to obtain supersaturation; the hot mixture is filtered to remove any insoluble impurities. The filtrate is allowed to cool. Crystals that form are filtered and washed with a solvent in which they are not soluble, but is miscible with the mother liquor; the process is repeated to increase the purity in a technique known as recrystallization. For biological molecules in which the solvent channels continue to be present to retain the three dimensional structure intact, microbatch crystallization under oil and vapor diffusion methods have been the common methods. Equipment for the main industrial processes for crystallization. Tank crystallizers. Tank crystallization is an old method still used in some specialized cases.
Saturated solutions, in tank crystallization, are allowed to cool in open tanks. After a period of time the mother liquo