Manhattan Project

Since the molecular weight ratio of UF compared to UFg is 349/352, the effusion rate of the lighter isotope is only 1.004 times that of the heavier one. The design of the porous membrane to affect the separation was an 

While the separations at Oak Ridge were mostly of a physical nature, dependent upon differences in atomic or molecular masses, separations at the Hanford site were mostly chemical in nature. Bombardment of uranium with neutrons produced Pu 239, a mixture of lighter metals, notably rare earths, created as nuclear fission by-products, and unchanged uranium. One consequence of the Hanford operation was the development of ion-exchange chromatography as a major purification and analytical method to separate the rare earths. It would become a general technique for separating ionic substances. 

Schematic depiction of Calvin s use of carbon 14 to label intermediates and discover the carbon pathway in photosynthesis 

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Another impetus to expansion of this field was the advent of World War 11 and the development of the atomic bomb. The desired isotope of uranium, in the form of UF was prepared by a gaseous diffusion separation process of the mixed isotopes (see Fluorine). UF is extremely reactive and required contact with inert organic materials as process seals and greases. The wartime Manhattan Project successfully developed a family of stable materials for UF service. These early materials later evolved into the current fluorochemical and fluoropolymer materials industry. A detailed description of the fluorine research performed on the Manhattan Project has been pubUshed (2). 

Many challenging industrial and military applications utilize polychlorotriduoroethylene [9002-83-9] (PCTFE) where, ia addition to thermal and chemical resistance, other unique properties are requited ia a thermoplastic polymer. Such has been the destiny of the polymer siace PCTFE was initially synthesized and disclosed ia 1937 (1). The synthesis and characterization of this high molecular weight thermoplastic were researched and utilized duting the Manhattan Project (2). The unique comhination of chemical iaertness, radiation resistance, low vapor permeabiUty, electrical iasulation properties, and thermal stabiUty of this polymer filled an urgent need for a thermoplastic material for use ia the gaseous UF diffusion process for the separation of uranium isotopes (see Diffusion separation methods). 

S. Groueff, Manhattan Project The Untold Story of the Making of the Atomic Bomb, Bantam Books, New York, 1967, pp. 211—219. 

Natural uranium consists mostly of and 0.711 wt % plus an inconsequential amount of The United States was the first country to employ the gaseous diffusion process for the enrichment of the fissionable natural uranium isotope. During the 1940s and 1950s, this enrichment appHcation led to the investment of several bUHon dollars in process faciHties. The original plants were built in 1943—1945 in Oak Ridge, Teimessee, as part of the Manhattan Project of World War II. 

Fluorine. Fluorine is the most reactive product of all electrochemical processes (63). It was first prepared in 1886, but important quantities of fluorine were not produced until the early 1940s. Fluorine was required for the production of uranium hexafluoride [7783-81 -5] UF, necessary for the enrichment of U (see DIFFUSION SEPARATION METHODS). The Manhattan Project in the United States and the Tube Alloy project in England contained parallel developments of electrolytic cells for fluorine production (63). The principal use of fluorine continues to be the production of UF from UF. ... 

Monte Carlo search methods are stochastic techniques based on the use of random numbers and probability statistics to sample conformational space. The name Monte Carlo was originally coined by Metropolis and Ulam [4] during the Manhattan Project of World War II because of the similarity of this simulation technique to games of chance. Today a variety of Monte Carlo (MC) simulation methods are routinely used in diverse fields such as atmospheric studies, nuclear physics, traffic flow, and, of course, biochemistry and biophysics. In this section we focus on the application of the Monte Carlo method for... 

One of the papers published in the first issue of JCP, by F.G. Foote and E.R. Jette, was devoted to the defect structure of FeO and is widely regarded as a classic. Frank Foote (1906-1998), a metallurgist, later became renowned for his contribution to the Manhattan Project and to nuclear metallurgy generally so chemical physics certainly did not exclude metallurgy. 

Finally, the borohydrides An(BFl4)4 must be mentioned.Those of Th and U were originally prepared as part of the Manhattan Project and those of Pa, Np and Pu have been prepared more recently, all by the general reaction... 

The origins of the national laboratoiy network can be traced back to the late 1940s and the beginning of the atomic age. At the end of World War II, the scientific community, particularly the staffs from the Manhattan Project laboratories, lobbied Congress for civilian control of atomic power. Toward this end, the federal government transferred authority from the Army to the newly established Atomic Energy... 

INEL s origins were as one of the satellite facilities for the Manhattan Project in the 1940s. Since the early... 

Ground breaking for the Clinton Laboratories, what Oak Ridge was originally called, occurred in Eebruai y 1943. Whereas the Manhattan Project at Los Alamos served as the center of weapons design,... 

Since the earliest days of the atomic age, physicists and engineers have predicted the coming of practicable nuclear fusion within ten years or a generation. Histoi y therefore offers many reasons to be skeptical about the promise of nuclear energy. At the same time, this unparalleled form of energy is not going to return to the Pandora s box pried open by the Manhattan Project more than a half century ago. 

The Manhattan Project at the University of Chicago Laboratoi"y, headed by Enrico Fermi (Italian-American), creates the first self-sustaining nuclear chain reaction. Natural gas liquified for first time in Cleveland, Ohio. 

July 16. First atomic bomb test at Aamogordo, New Mexico, under the code name Manhattan Project. ... 

The gifted chemists who worked on the "Manhattan Project" recognized and attempted to quantitatively describe the effects of a self-radiolysis soon after the preparation of macroscopic quantities of 239Pu. The present symposium provides an appropriate time and place to cite a number of these individuals for their contributions to an important aspect of Pu solution chemistry. 

Large-scale plutonium recovery/processing facilities originated at Los Alamos and Hanford as part of the Manhattan Project in 1943. Hanford Operations separated plutonium from irradiated reactor fuel, whereas Los Alamos purified plutonium, as well as recovered the plutonium from scrap and residues. In the 1950 s, similar processing facilities were constructed at Rocky Flats and Savannah River. 

Disproportionation reactions of Pu(IV) (Equations 1 and 2) and Pu(V) (Equation 3) have been known and studied since Manhattan Project days.(24,25)... 

Complete dissolution of plutonium residues, especially high temperature calcined plutonium dioxide contained in residues such as incinerator ash, continues to cause problems, despite continued research since the Manhattan Project (9). Methods to improve the Rocky Flats system include the use of additives (e.g., cerium) and electrochemistry, other solvents (HCl-SnCl2) as well as high-temperature fusion methods (10). High pressure dissolution, HF preleaching, fluorination, and other methods are being investigated. 

Like many others at Oak Ridge, the Pattersons petitioned the Manhattan Project to explode a trial bomb on Japan s countryside before targeting a city. After the bomb developed at Oak Ridge was dropped on Hiroshima, Patterson came to regard the Manhattan Project as the greatest crime that science has committed yet.. . We burned 100,000 Japanese alive. .. [I] helped... 

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