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44-406: The AVR was based on the concept of a "Daniels pile" by Farrington Daniels , the inventor of pebble bed reactors. Rudolf Schulten is commonly recognized as the intellectual father of the reactor. A consortium of 15 community electric companies owned and operated the plant. Over its lifetime the reactor had many accidents, earning it the name "shipwreck." From 2011 to 2014, outside experts examined

88-463: A boy, he was fascinated with Thomas Edison , Samuel F. B. Morse , Alexander Graham Bell , and John Charles Fields . He decided early that he wanted to be an electrician and inventor. He attended Central and East Side high schools. By this point he liked chemistry and physics, but equally enjoyed "Manual Training." In 1906, he entered the University of Minnesota , majoring in chemistry and adding to

132-447: A chemical compound. Spectroscopy is the related sub-discipline of physical chemistry which is specifically concerned with the interaction of electromagnetic radiation with matter. Another set of important questions in chemistry concerns what kind of reactions can happen spontaneously and which properties are possible for a given chemical mixture. This is studied in chemical thermodynamics , which sets limits on quantities like how far

176-439: A limited extent, quasi-equilibrium and non-equilibrium thermodynamics can describe irreversible changes. However, classical thermodynamics is mostly concerned with systems in equilibrium and reversible changes and not what actually does happen, or how fast, away from equilibrium. Which reactions do occur and how fast is the subject of chemical kinetics , another branch of physical chemistry. A key idea in chemical kinetics

220-667: A mass market edition in 1974 by Ballantine Books , after the 1973 oil crisis , and was described as "The best book on solar energy that I know of" by the Whole Earth Catalog 's Steve Baer . Physical chemistry Physical chemistry is the study of macroscopic and microscopic phenomena in chemical systems in terms of the principles, practices, and concepts of physics such as motion , energy , force , time , thermodynamics , quantum chemistry , statistical mechanics , analytical dynamics and chemical equilibria . Physical chemistry, in contrast to chemical physics ,

264-471: A mixture, is a special case of another key concept in physical chemistry, which is that to the extent an engineer needs to know, everything going on in a mixture of very large numbers (perhaps of the order of the Avogadro constant , 6 x 10 ) of particles can often be described by just a few variables like pressure, temperature, and concentration. The precise reasons for this are described in statistical mechanics ,

308-402: A reaction can proceed, or how much energy can be converted into work in an internal combustion engine , and which provides links between properties like the thermal expansion coefficient and rate of change of entropy with pressure for a gas or a liquid . It can frequently be used to assess whether a reactor or engine design is feasible, or to check the validity of experimental data. To

352-590: A regret about its failures and scientific misconduct with respect to the AVR. Farrington Daniels Farrington Daniels (March 8, 1889 – June 23, 1972) was an American physical chemist who is considered one of the pioneers of the modern direct use of solar energy . Daniels was born in Minneapolis, Minnesota on March 8, 1889. Daniels began day school in 1895 at the Kenwood School and then on to Douglas School. As

396-540: A specialty within physical chemistry which is also shared with physics. Statistical mechanics also provides ways to predict the properties we see in everyday life from molecular properties without relying on empirical correlations based on chemical similarities. The term "physical chemistry" was coined by Mikhail Lomonosov in 1752, when he presented a lecture course entitled "A Course in True Physical Chemistry" ( Russian : Курс истинной физической химии ) before

440-453: A teaching fellowship, and received a PhD in 1914. His doctoral research on the electrochemistry of thallium alloys was supervised by Theodore William Richards . In the summer of 1912, Daniels had visited England and Europe. After earning his PhD, Harvard would have sent him on a traveling fellowship in Europe, but World War I broke out. So instead he accepted a position as instructor at

484-410: Is applied to chemical problems. One of the key concepts in classical chemistry is that all chemical compounds can be described as groups of atoms bonded together and chemical reactions can be described as the making and breaking of those bonds. Predicting the properties of chemical compounds from a description of atoms and how they bond is one of the major goals of physical chemistry. To describe

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528-610: Is located next to the largest open-pit coal mine in Germany, the Tagebau Hambach . In 1959, 15 municipal electric companies established the "Association of Experimental Reactor GmbH" (AVR Ltd) to demonstrate the feasibility and viability of a gas-cooled, graphite-moderated high temperature reactor. In 1961, BBC and Krupp began AVR construction, led by Rudolf Schulten , performed on almost purely industrial basis until 1964. The federal government provided financial assistance, supported by

572-416: Is predominantly (but not always) a supra-molecular science, as the majority of the principles on which it was founded relate to the bulk rather than the molecular or atomic structure alone (for example, chemical equilibrium and colloids ). Some of the relationships that physical chemistry strives to understand include the effects of: The key concepts of physical chemistry are the ways in which pure physics

616-586: Is probably the most important 20th century development. Further development in physical chemistry may be attributed to discoveries in nuclear chemistry , especially in isotope separation (before and during World War II), more recent discoveries in astrochemistry , as well as the development of calculation algorithms in the field of "additive physicochemical properties" (practically all physicochemical properties, such as boiling point, critical point, surface tension, vapor pressure, etc.—more than 20 in all—can be precisely calculated from chemical structure alone, even if

660-443: Is that for reactants to react and form products , most chemical species must go through transition states which are higher in energy than either the reactants or the products and serve as a barrier to reaction. In general, the higher the barrier, the slower the reaction. A second is that most chemical reactions occur as a sequence of elementary reactions , each with its own transition state. Key questions in kinetics include how

704-554: The Argonne National Laboratory , serving as first chairman of its Board of Governors from 1946 until 1948. It was in that role, in 1947, that Daniels conceived the pebble bed reactor , a reactor design in which helium rises through fissioning uranium oxide or carbide pebbles, cooling them by carrying away heat for power production. The "Daniels' pile" was an early version of the later high-temperature gas-cooled reactor developed further at ORNL without success, but which

748-416: The University of Wisconsin–Madison 's Solar Energy Laboratory, he explored such areas of practical application as cooking , space heating , agricultural and industrial drying, distillation , cooling and refrigeration , and photo- and thermo-electric conversion , and he was also interested in energy storage . In particular, he believed there were many practical applications of solar energy for ready use in

792-547: The Worcester Polytechnic Institute , where, besides teaching, he found he had considerable time for research in calorimetry , for which he received a grant from the American Academy of Arts and Sciences . He joined the University of Wisconsin in 1920 as an assistant professor in 1920, and remained until his retirement in 1959 as chairman of the chemistry department. During World War II , Daniels joined

836-600: The developing world . Daniels was active with the Association for Applied Solar Energy in the mid-1950s. He suggested that AFASE embark upon the publication of a scientific journal, and the first issue of The Journal of Solar Energy Science and Engineering appeared in January, 1957. Later, as Professor Emeritus of Chemistry of the University of Wisconsin–Madison , he led a group of solar scientists who proposed that AFASE be reorganized, that its directors and officers be elected by

880-414: The 21st century. After the AVR vessel is moved into intermediate storage, the reactor buildings will be dismantled, and soil and groundwater will be decontaminated. Costs from 1988 to present are €700 million. The total AVR decommissioning costs are expected to be in the order of €1.5 to 2.5 billion, all public funds, i.e. to exceed its construction costs by far. From 2011 to 2014, outside experts examined

924-505: The AVR GmbH to ensure continued operation, since electricity generation only covered a small part of the operating costs . In the mid-1970s annual revenue was about 3 million DM, versus operating and fuel disposal costs of 11 million DM. JRC also subsidized AVR through procurement and disposal of fuel as JRC has been owner of AVR fuel. In addition, the AVR operation was scientifically supervised by JRC. From 1974 to 1978, mainly carbide BISO fuel

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968-505: The German government in February 2010. Fuel removal out of AVR was difficult and lasted four years. During this time it became obvious that the AVR bottom reflector was broken; about 200 fuel pebbles remain wedged in its crack. Currently no dismantling method for the AVR vessel exists. It is planned to develop some procedure during the next 60 years and to start with vessel dismantling at the end of

1012-414: The atoms and bonds precisely, it is necessary to know both where the nuclei of the atoms are, and how electrons are distributed around them. Quantum chemistry , a subfield of physical chemistry especially concerned with the application of quantum mechanics to chemical problems, provides tools to determine how strong and what shape bonds are, how nuclei move, and how light can be absorbed or emitted by

1056-600: The casks to the United States have been considered due to the extremely high disposal expenses. In 2014, a massive concrete wall to protect against terrorist plane crashes was to be built. On July 2, 2014, the Federal Environment ministry issued an evacuation order for the temporary storage. AVR was the basis of the technology licensed to China to build HTR-10 and the HTR-PM , which became operational in 2021. The reactor

1100-474: The chemical molecule remains unsynthesized), and herein lies the practical importance of contemporary physical chemistry. See Group contribution method , Lydersen method , Joback method , Benson group increment theory , quantitative structure–activity relationship Some journals that deal with physical chemistry include Historical journals that covered both chemistry and physics include Annales de chimie et de physique (started in 1789, published under

1144-474: The core. Helium flowed up through the core of pebbles. AVR's helium outlet temperature was 950 °C, but fuel temperature instabilities occurred during operation with localised exceedingly high temperatures. As a consequence the whole reactor vessel became heavily contaminated by Cs and Sr . Concerning beta-contamination AVR is the highest contaminated nuclear installation worldwide as AVR management confirmed 2001. Thus in 2008,

1188-414: The development of quantum mechanics into quantum chemistry from the 1930s, where Linus Pauling was one of the leading names. Theoretical developments have gone hand in hand with developments in experimental methods, where the use of different forms of spectroscopy , such as infrared spectroscopy , microwave spectroscopy , electron paramagnetic resonance and nuclear magnetic resonance spectroscopy ,

1232-457: The historical operations and operational hazards and described serious concealed problems and wrongdoings in their final 2014 report. For example, in 1978 operators bypassed reactor shutdown controls to delay an emergency shutdown during an accident for six days. In 2014 the JRC and AVR publicly admitted to failures. Its decommissioning has been exceptionally difficult, time-consuming and expensive. Since

1276-470: The historical operations and operational hazards and in April 2014, published a report on the AVR operation. The report listed hidden or downplayed events and accidents and described serious concealed problems and wrongdoings. For example, in 1978 operators bypassed reactor shutdown controls to delay an emergency shutdown during an accident for six days. In 2014 the JRC and AVR publicly admitted to failures and issued

1320-507: The leading figures in physical chemistry in the late 19th century and early 20th century. All three were awarded the Nobel Prize in Chemistry between 1901 and 1909. Developments in the following decades include the application of statistical mechanics to chemical systems and work on colloids and surface chemistry , where Irving Langmuir made many contributions. Another important step was

1364-456: The membership, and that the name be changed to The Solar Energy Society – all of which was done. He supported solar energy because, as he said in 1955, "We realize, as never before, that our fossil fuels – coal, oil, and gas – will not last forever." One of his classic books is Direct Use of the Sun's Energy , published by Yale University Press in 1964. The book was reprinted in

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1408-426: The original operators were overwhelmed by the effort, government agencies took over dismantling and disposal. In 2003 the reactor and its nuclear waste became government property. The temporary storage of 152 casks of spent fuel has been a controversy since 2009. The approval expired in 2013, because stress tests could not sufficiently demonstrate safety; no permanent solution has been reached. Since 2012 plans to export

1452-577: The politician and founder of the Jülich Research Center (JRC), Leo Brandt. In 1964, Schulten became Director of the JRC and started to devote more attention to the pebble bed reactor. In 1966, AVR first achieved criticality, and was connected to the national power grid in 1967. Construction cost figures vary between 85 and 125 million Deutsche marks Since about 1970 the AVR GmbH was de facto dependent on JRC, although it remained formally independent until 2003. JRC provided generous operating grants to

1496-412: The rate of reaction depends on temperature and on the concentrations of reactants and catalysts in the reaction mixture, as well as how catalysts and reaction conditions can be engineered to optimize the reaction rate. The fact that how fast reactions occur can often be specified with just a few concentrations and a temperature, instead of needing to know all the positions and speeds of every molecule in

1540-419: The reactor vessel was filled with light concrete to fixate the radioactive fine particle dust. In 2012, the reactor vessel of 2100 metric tons was to be transported about 200 meters by air-cushion sled and seven cranes to an intermediate storage site. During a severe water accident in 1978, Sr leaked, and in 1999 soil and groundwater contamination below the reactor was discovered, as confirmed by

1584-542: The staff of the Metallurgical Laboratory , a part of the Manhattan Project effort by the United States to develop the first nuclear weapons. He served first as associate director of the laboratory's chemistry division from the summer of 1944 before, on July 1, 1945, becoming overall director of that institution, a post held until May 1946. He was active in the planning of the laboratory's immediate successor,

1628-459: The students of Petersburg University . In the preamble to these lectures he gives the definition: "Physical chemistry is the science that must explain under provisions of physical experiments the reason for what is happening in complex bodies through chemical operations". Modern physical chemistry originated in the 1860s to 1880s with work on chemical thermodynamics , electrolytes in solutions, chemical kinetics and other subjects. One milestone

1672-683: The suitability of the AVR for coal gasification , and thus contribute to long-term plans for coal in Northrhine-Westfalia . Because a pebble bed core cannot be equipped with instruments, the high AVR core temperatures were unknown until one year before the AVR shut-down, in 1988. In 2000, AVR admitted that it was contaminated with 100  TBq Sr , being the most heavily Sr contaminated nuclear facility worldwide. The core held about 100,000 fuel element pebbles. Each contained about 1g of U . On average each would take 6 to 8 months to pass through

1716-500: The usual mathematics and analytical courses some courses in botany and scientific German. He was initiated into the Beta Chapter of Alpha Chi Sigma in 1908. He sometimes worked summers as a railroad surveyor . He took his degree in chemistry in 1910. The following year he spent half his time in teaching and received an MS for graduate work in physical chemistry . He entered Harvard in 1911, paying for his studies partly through

1760-760: Was developed later as nuclear power reactor by Rudolf Schulten . Daniels became concerned to limit or stop the nuclear arms race after the war. In that regard, he became a board member of the Bulletin of the Atomic Scientists . Daniels is also known for writing several textbooks on physical chemistry , including Mathematical preparation for physical chemistry (1928), Experimental physical chemistry , co-authored with J. Howard Mathews and John Warren (1934), Chemical Kinetics (1938), Physical Chemistry , co-authored with Robert Alberty (1957). Some of these books went through many subsequent editions until about 1980. He

1804-726: Was elected in 1928 a Fellow of the American Association for the Advancement of Science (AAAS). He was elected to the United States National Academy of Sciences in 1947 and the American Philosophical Society in 1948. He was awarded the Priestley Medal and elected to the American Academy of Arts and Sciences in 1957. Daniels died on June 23, 1972, from complications from liver cancer . He

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1848-517: Was in the core. From 1983 to 1988, oxide fuel with TRISO particles was used. During its initial years (1967-1973) the AVR was nominally operated with cooling gas outlet temperatures of 650–850 °C . In February 1974, the cooling gas outlet temperature was raised to 950 °C. These final high temperatures were a world record for nuclear facilities, though later exceeded by the US test reactor UHTREX . Such high temperatures were supposed to demonstrate

1892-494: Was survived by his wife, four children, and twelve grandchildren. He was inducted posthumously to the Alpha Chi Sigma Hall of Fame in 1982. Daniels became a leading American expert on the principles involved with the practical utilization of solar energy. He pursued understanding of the heat and the convection that can be derived from it, as well as the electrical energy that could be derived from it. As Director of

1936-594: Was the publication in 1876 by Josiah Willard Gibbs of his paper, On the Equilibrium of Heterogeneous Substances . This paper introduced several of the cornerstones of physical chemistry, such as Gibbs energy , chemical potentials , and Gibbs' phase rule . The first scientific journal specifically in the field of physical chemistry was the German journal, Zeitschrift für Physikalische Chemie , founded in 1887 by Wilhelm Ostwald and Jacobus Henricus van 't Hoff . Together with Svante August Arrhenius , these were

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