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68-505: The Vinča Institute of Nuclear Sciences is a nuclear physics research institution near Belgrade , Serbia. Since its founding, the institute has also conducted research in the fields in physics, chemistry and biology. The scholarly institute is part of the University of Belgrade . The institute was established in 1948 as the Institute for Physics. Several different research groups started in

136-526: A classical system , rather than a quantum-mechanical one. In the resulting liquid-drop model , the nucleus has an energy that arises partly from surface tension and partly from electrical repulsion of the protons. The liquid-drop model is able to reproduce many features of nuclei, including the general trend of binding energy with respect to mass number, as well as the phenomenon of nuclear fission . Superimposed on this classical picture, however, are quantum-mechanical effects, which can be described using

204-493: A phase transition from normal nuclear matter to a new state, the quark–gluon plasma , in which the quarks mingle with one another, rather than being segregated in triplets as they are in neutrons and protons. Eighty elements have at least one stable isotope which is never observed to decay, amounting to a total of about 251 stable nuclides. However, thousands of isotopes have been characterized as unstable. These "radioisotopes" decay over time scales ranging from fractions of

272-408: A different number of protons. In alpha decay , which typically occurs in the heaviest nuclei, the radioactive element decays by emitting a helium nucleus (2 protons and 2 neutrons), giving another element, plus helium-4 . In many cases this process continues through several steps of this kind, including other types of decays (usually beta decay) until a stable element is formed. In gamma decay ,

340-518: A gratis website, Scopus CiteScore, was introduced. It provides citation data for all 25,000+ active titles such as journals, conference proceedings and books in Scopus and provides an alternative to the impact factor , a journal-level indicator which may correlate negatively with reliability. Scopus IDs for individual authors can be integrated with the non-proprietary digital identifier ORCID . In 2018, Scopus started embedding partial information about

408-421: A low dose of radiation. Mathé operated on all five of them, performing the first successful allogeneic bone marrow transplant ever performed on unrelated human beings. The donors were all French: Marcel Pabion, Albert Biron, Raymond Castanier, and Odette Draghi—mother of four young children. The fifth donor was Léon Schwartzenberg  [ fr ] , a member of Mathé's team. On 11 November 1958, Maksić became

476-408: A nucleus decays from an excited state into a lower energy state, by emitting a gamma ray . The element is not changed to another element in the process (no nuclear transmutation is involved). Other more exotic decays are possible (see the first main article). For example, in internal conversion decay, the energy from an excited nucleus may eject one of the inner orbital electrons from the atom, in

544-456: A number of countries. Scopus also allows patent searches from a dedicated patent database, Lexis-Nexis , albeit with limited functionality. Comparing ease of use and coverage of Scopus and the Web of Science (WOS), a 2006 study concluded that Scopus is "easy to navigate, even for the novice user. ... The ability to search both forward and backward from a particular citation would be very helpful to

612-518: A process which produces high speed electrons but is not beta decay and (unlike beta decay) does not transmute one element to another. In nuclear fusion , two low-mass nuclei come into very close contact with each other so that the strong force fuses them. It requires a large amount of energy for the strong or nuclear forces to overcome the electrical repulsion between the nuclei in order to fuse them; therefore nuclear fusion can only take place at very high temperatures or high pressures. When nuclei fuse,

680-488: A second to trillions of years. Plotted on a chart as a function of atomic and neutron numbers, the binding energy of the nuclides forms what is known as the valley of stability . Stable nuclides lie along the bottom of this energy valley, while increasingly unstable nuclides lie up the valley walls, that is, have weaker binding energy. The most stable nuclei fall within certain ranges or balances of composition of neutrons and protons: too few or too many neutrons (in relation to

748-507: A spin of ± + 1 ⁄ 2 . In the Rutherford model of nitrogen-14, 20 of the total 21 nuclear particles should have paired up to cancel each other's spin, and the final odd particle should have left the nucleus with a net spin of 1 ⁄ 2 . Rasetti discovered, however, that nitrogen-14 had a spin of 1. In 1932 Chadwick realized that radiation that had been observed by Walther Bothe , Herbert Becker , Irène and Frédéric Joliot-Curie

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816-494: A very large amount of energy is released and the combined nucleus assumes a lower energy level. The binding energy per nucleon increases with mass number up to nickel -62. Stars like the Sun are powered by the fusion of four protons into a helium nucleus, two positrons , and two neutrinos . The uncontrolled fusion of hydrogen into helium is known as thermonuclear runaway. A frontier in current research at various institutions, for example

884-402: Is a measure reflecting the yearly average number of citations to recent articles published in that journal. It is produced by Elsevier , based on the citations recorded in the Scopus database. Absolute rankings and percentile ranks are also reported for each journal in a given subject area. An article published by "Scholarly Criticism" in 2024 alleges that Elsevier unethically indexed

952-416: Is a scientific abstract and citation database , launched by the academic publisher Elsevier as a competitor to older Web of Science in 2004. An ensuing competition between the two databases has been characterized as "intense" and is considered to significantly benefit their users in terms of continuous improvent in coverage, search/analysis capabilities, but not in price. Free database The Lens completes

1020-412: Is held together by the strong nuclear force, unless it is too large. Unstable nuclei may undergo alpha decay, in which they emit an energetic helium nucleus, or beta decay, in which they eject an electron (or positron ). After one of these decays the resultant nucleus may be left in an excited state, and in this case it decays to its ground state by emitting high-energy photons (gamma decay). The study of

1088-516: Is potentially hazardous for the health and safety of the wider area of Serbia, not just for Belgrade. Additionally, after removing all the radioactive waste, the institute can truly be transformed into the modern scientific-business park. Vinča Nuclear Institute is a publisher of three journals, two among them are listed in Scopus and WoS : Thermal Science and Nuclear Technology & Radiation Protection . Nuclear physics Nuclear physics

1156-471: Is still closed. Though, it is meant to be only a transition location where the processed waste from H1 is to be kept before being transported to the permanent location. Still, as of 2018, large quantities of nuclear waste remain in the institute, the permanent location hasn't been selected, and the waste is not being treated and processed at all. The waste in Vinča is of low to mid-level radioactivity, which means it

1224-638: Is the field of physics that studies atomic nuclei and their constituents and interactions, in addition to the study of other forms of nuclear matter . Nuclear physics should not be confused with atomic physics , which studies the atom as a whole, including its electrons . Discoveries in nuclear physics have led to applications in many fields. This includes nuclear power , nuclear weapons , nuclear medicine and magnetic resonance imaging , industrial and agricultural isotopes, ion implantation in materials engineering , and radiocarbon dating in geology and archaeology . Such applications are studied in

1292-410: Is the preferred option for chemical searches is all cases. Scopus also offers author profiles which cover affiliations, number of publications and their bibliographic data, references , and details on the number of citations each published document has received. It has alerting features that allow registered users to track changes to a profile and a facility to calculate authors' h -index . In 2016,

1360-459: Is the source of energy for nuclear power plants and fission-type nuclear bombs, such as those detonated in Hiroshima and Nagasaki , Japan, at the end of World War II . Heavy nuclei such as uranium and thorium may also undergo spontaneous fission , but they are much more likely to undergo decay by alpha decay. For a neutron-initiated chain reaction to occur, there must be a critical mass of

1428-685: Is updated 2 to 3 times per year. Each year Scopus receives around 3,500 submissions for new titles to be included and accepts approximately 25% of them. The re-evaluation policy is based on four criteria of Publication Concern, Under Performance, Outlier Performance and Continuous curation. Between 2004 and 2020, Scopus included 41,525 and excluded 688 titles Between 2016 and 2023, the CSAB has re-evaluated 990 titles published by 539 different publishers, leading to 536 titles discontinued for indexing. In 2024 Scopus covered around 28,000 active journals and nearly 300,000 books. Nevertheless, research continues to show

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1496-466: The Joint European Torus (JET) and ITER , is the development of an economically viable method of using energy from a controlled fusion reaction. Nuclear fusion is the origin of the energy (including in the form of light and other electromagnetic radiation) produced by the core of all stars including our own Sun. Nuclear fission is the reverse process to fusion. For nuclei heavier than nickel-62

1564-433: The nuclear shell model , developed in large part by Maria Goeppert Mayer and J. Hans D. Jensen . Nuclei with certain " magic " numbers of neutrons and protons are particularly stable, because their shells are filled. Other more complicated models for the nucleus have also been proposed, such as the interacting boson model , in which pairs of neutrons and protons interact as bosons . Ab initio methods try to solve

1632-428: The open access status of works, using Unpaywall data. However, Scopus' ris export files do not contain the information about Open Access status. Since Elsevier is the owner of Scopus and is also one of the main international publishers of scientific journals, an independent and international Scopus Content Selection and advisory board (CSAB) was established in 2009 to prevent a potential conflict of interest in

1700-462: The "heavier elements" (carbon, element number 6, and elements of greater atomic number ) that we see today, were created inside stars during a series of fusion stages, such as the proton–proton chain , the CNO cycle and the triple-alpha process . Progressively heavier elements are created during the evolution of a star. Energy is only released in fusion processes involving smaller atoms than iron because

1768-464: The 1950s, and two research reactors were built. The institute operates two research reactors; RA and RB. The research reactors were supplied by the USSR . The larger of the two reactors was rated at 6.5 MW and used Soviet-supplied 80% enriched uranium fuel. The nuclear research program ended in 1968; the reactors were switched off in 1984. On 15 October 1958, there was a criticality accident at one of

1836-422: The Scopus keywords are more focused on the specific article content, whereas WoS has more keywords related to the broad category of the article's subject. A larger number of narrow-targeted keywords allows Scopus users to find a larger number of relevant publications, while filtering out false positives. On the other hand, WoS exports (e.g. in the ris format) the doi numbers of cited articles, while Scopus exports

1904-403: The atom, in which the atom had a very small, very dense nucleus containing most of its mass, and consisting of heavy positively charged particles with embedded electrons in order to balance out the charge (since the neutron was unknown). As an example, in this model (which is not the modern one) nitrogen-14 consisted of a nucleus with 14 protons and 7 electrons (21 total particles) and the nucleus

1972-453: The beta decay spectrum was continuous rather than discrete. That is, electrons were ejected from the atom with a continuous range of energies, rather than the discrete amounts of energy that were observed in gamma and alpha decays. This was a problem for nuclear physics at the time, because it seemed to indicate that energy was not conserved in these decays. The 1903 Nobel Prize in Physics

2040-538: The binding energy per nucleon peaks around iron (56 nucleons). Since the creation of heavier nuclei by fusion requires energy, nature resorts to the process of neutron capture. Neutrons (due to their lack of charge) are readily absorbed by a nucleus. The heavy elements are created by either a slow neutron capture process (the so-called s -process ) or the rapid , or r -process . The s process occurs in thermally pulsing stars (called AGB, or asymptotic giant branch stars) and takes hundreds to thousands of years to reach

2108-486: The binding energy per nucleon decreases with the mass number. It is therefore possible for energy to be released if a heavy nucleus breaks apart into two lighter ones. The process of alpha decay is in essence a special type of spontaneous nuclear fission . It is a highly asymmetrical fission because the four particles which make up the alpha particle are especially tightly bound to each other, making production of this nucleus in fission particularly likely. From several of

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2176-413: The choice of journals to be included in the database and to maintain an open and transparent content coverage policy, regardless of publisher. The board consists of scientists and subject librarians. Nevertheless, critique over a perceived conflict of interest has continued. CSAB team is responsible for inclusion and exclusion of different titles on Scopus. The list of journals and books indexed in Scopus

2244-542: The content of Proca's equations for developing a theory of the atomic nuclei in Nuclear Physics. In 1935 Hideki Yukawa proposed the first significant theory of the strong force to explain how the nucleus holds together. In the Yukawa interaction a virtual particle , later called a meson , mediated a force between all nucleons, including protons and neutrons. This force explained why nuclei did not disintegrate under

2312-474: The discovery of radioactivity by Henri Becquerel in 1896, made while investigating phosphorescence in uranium salts. The discovery of the electron by J. J. Thomson a year later was an indication that the atom had internal structure. At the beginning of the 20th century the accepted model of the atom was J. J. Thomson's "plum pudding" model in which the atom was a positively charged ball with smaller negatively charged electrons embedded inside it. In

2380-426: The equivalence of mass and energy to within 1% as of 1934. Alexandru Proca was the first to develop and report the massive vector boson field equations and a theory of the mesonic field of nuclear forces . Proca's equations were known to Wolfgang Pauli who mentioned the equations in his Nobel address, and they were also known to Yukawa, Wentzel, Taketani, Sakata, Kemmer, Heitler, and Fröhlich who appreciated

2448-418: The field of nuclear engineering . Particle physics evolved out of nuclear physics and the two fields are typically taught in close association. Nuclear astrophysics , the application of nuclear physics to astrophysics , is crucial in explaining the inner workings of stars and the origin of the chemical elements . The history of nuclear physics as a discipline distinct from atomic physics , starts with

2516-400: The first man to receive a graft from an unrelated donor (Pabion). Out of five treated patients, only Vranić died. The others recovered and returned to Belgrade to continue working in Vinča or other institutes. Several years later, Dangubić gave birth to a healthy baby girl. In the 1980s, the waste was kept in the open. The waste was then transferred into two hangars, H1 and H2, while the ground

2584-412: The foil with their trajectories being at most slightly bent. But Rutherford instructed his team to look for something that shocked him to observe: a few particles were scattered through large angles, even completely backwards in some cases. He likened it to firing a bullet at tissue paper and having it bounce off. The discovery, with Rutherford's analysis of the data in 1911, led to the Rutherford model of

2652-747: The heat emanating from the Earth's core results from radioactive decay. However, it is not known if any of this results from fission chain reactions. According to the theory, as the Universe cooled after the Big Bang it eventually became possible for common subatomic particles as we know them (neutrons, protons and electrons) to exist. The most common particles created in the Big Bang which are still easily observable to us today were protons and electrons (in equal numbers). The protons would eventually form hydrogen atoms. Almost all

2720-511: The heaviest elements of lead and bismuth. The r -process is thought to occur in supernova explosions , which provide the necessary conditions of high temperature, high neutron flux and ejected matter. These stellar conditions make the successive neutron captures very fast, involving very neutron-rich species which then beta-decay to heavier elements, especially at the so-called waiting points that correspond to more stable nuclides with closed neutron shells (magic numbers). Scopus Scopus

2788-439: The heaviest nuclei whose fission produces free neutrons, and which also easily absorb neutrons to initiate fission, a self-igniting type of neutron-initiated fission can be obtained, in a chain reaction . Chain reactions were known in chemistry before physics, and in fact many familiar processes like fires and chemical explosions are chemical chain reactions. The fission or "nuclear" chain-reaction , using fission-produced neutrons,

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2856-415: The inclusion of predatory journals . While marketed as a global point of reference, Scopus and WoS have been characterised as "structurally biased against research produced in non-Western countries, non-English language research, and research from the arts, humanities, and social sciences". or Science-wide author databases of standardized citation indicators CiteScore (CS) of an academic journal

2924-417: The influence of proton repulsion, and it also gave an explanation of why the attractive strong force had a more limited range than the electromagnetic repulsion between protons. Later, the discovery of the pi meson showed it to have the properties of Yukawa's particle. With Yukawa's papers, the modern model of the atom was complete. The center of the atom contains a tight ball of neutrons and protons, which

2992-705: The journal Heliyon , which is published by Elsevier's subsiduary, in Scopus within a few months of its launch. This indexing occurred with one citation and four published issues in 2015, which the article suggests does not align with the rules prescribed for other journals. The article further alleges that Elsevier was motivated to engage in this practice, which the article calls a "conflict of interest," in order to attract authors to publish in Heliyon, which charges an article processing charge of USD 2,100 per publication. In 2024 French National Centre for Scientific Research CNRS ended its subscription to Scopus, while maintaining for

3060-418: The neutrons created in the Big Bang were absorbed into helium-4 in the first three minutes after the Big Bang, and this helium accounts for most of the helium in the universe today (see Big Bang nucleosynthesis ). Some relatively small quantities of elements beyond helium (lithium, beryllium, and perhaps some boron) were created in the Big Bang, as the protons and neutrons collided with each other, but all of

3128-660: The nuclear many-body problem from the ground up, starting from the nucleons and their interactions. Much of current research in nuclear physics relates to the study of nuclei under extreme conditions such as high spin and excitation energy. Nuclei may also have extreme shapes (similar to that of Rugby balls or even pears ) or extreme neutron-to-proton ratios. Experimenters can create such nuclei using artificially induced fusion or nucleon transfer reactions, employing ion beams from an accelerator . Beams with even higher energies can be used to create nuclei at very high temperatures, and there are signs that these experiments have produced

3196-460: The nuclear waste allows decommissioning of Vinča's remaining reactor to be completed. In 2012 the Law on Radiation Protection and Nuclear Safety was adopted. It envisioned that within 10 years, that is by 2022, the waste from Vinča must be transferred to the permanent and safe depository location. A new and modern hangar, H3, was built in the meantime but due to the legal procedures and licensing problems it

3264-409: The number of protons) will cause it to decay. For example, in beta decay , a nitrogen -16 atom (7 protons, 9 neutrons) is converted to an oxygen -16 atom (8 protons, 8 neutrons) within a few seconds of being created. In this decay a neutron in the nitrogen nucleus is converted by the weak interaction into a proton, an electron and an antineutrino . The element is transmuted to another element, with

3332-471: The origin of the ozone, but by that time they were already irradiated. The news was briefly broadcast by the state agency Tanjug , but the news on the incident was then suppressed. The reasons included the fact that the state commission concluded that the incident was caused by the researchers' carelessness and indiscipline. The patients were first treated in Belgrade, under the care of Dr. Vasa Janković. Thanks to

3400-401: The period between 1990 and 2020. In terms of the structured query language search capabilities Scopus is somewhat more advanced than Web of Science : for example, WoS can perform only NEAR/n queries, Scopus can also do PRE/n queries. Also, when the same article was covered in Scopus and in the Web of Science (WoS), its Scopus entry had a keyword ratio 3-5 of than its WoS counterpart, and

3468-512: The personal connections of the Institute director Pavle Savić , who was a collaborator of Irène and Frédéric Joliot-Curie , they were transferred to the Curie Institute in Paris . In Paris, they were treated by oncologist Georges Mathé . Five researchers were heavily radiated: Rosanda Dangubić, Života Vranić, Radojko Maksić, Draško Grujić and Stijepo Hajduković, while Živorad Bogojević received

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3536-574: The problem of the spin of nitrogen-14, as the one unpaired proton and one unpaired neutron in this model each contributed a spin of 1 ⁄ 2 in the same direction, giving a final total spin of 1. With the discovery of the neutron, scientists could at last calculate what fraction of binding energy each nucleus had, by comparing the nuclear mass with that of the protons and neutrons which composed it. Differences between nuclear masses were calculated in this way. When nuclear reactions were measured, these were found to agree with Einstein's calculation of

3604-498: The relevant isotope present in a certain space under certain conditions. The conditions for the smallest critical mass require the conservation of the emitted neutrons and also their slowing or moderation so that there is a greater cross-section or probability of them initiating another fission. In two regions of Oklo , Gabon, Africa, natural nuclear fission reactors were active over 1.5 billion years ago. Measurements of natural neutrino emission have demonstrated that around half of

3672-487: The research reactors. Six workers received large doses of radiation. One died shortly afterwards; the other five received the first ever bone marrow transplants in Europe. Six young researchers, all between 24 and 26 years of age, were conducting an experiment on the reactor, and the results were to be used by one student for his thesis . At some point, they smelled the strong scent of ozone. It took them 10 minutes to discover

3740-427: The researcher. The multidisciplinary aspect allows the researcher to easily search outside of his discipline" and "One advantage of WOS over Scopus is the depth of coverage, with the full WOS database going back to 1945 and Scopus going back to 1966. However, Scopus and WOS complement each other as neither resource is all-inclusive." A small number of studies found ca. 80-90% overlap in coverage between WoS and Scopus for

3808-524: The source of the energy of radioactivity would have to wait for the discovery that the nucleus itself was composed of smaller constituents, the nucleons . In 1906, Ernest Rutherford published "Retardation of the α Particle from Radium in passing through matter." Hans Geiger expanded on this work in a communication to the Royal Society with experiments he and Rutherford had done, passing alpha particles through air, aluminum foil and gold leaf. More work

3876-486: The strong and weak nuclear forces (the latter explained by Enrico Fermi via Fermi's interaction in 1934) led physicists to collide nuclei and electrons at ever higher energies. This research became the science of particle physics , the crown jewel of which is the standard model of particle physics , which describes the strong, weak, and electromagnetic forces . A heavy nucleus can contain hundreds of nucleons . This means that with some approximation it can be treated as

3944-437: The titles of cited articles. Also, Scopus allows exporting 20,000 references (e.g. as a ris file) at once, while WoS export is limited to 5,000 references at once. Scopus provides chemical search by CAS number and by chemical name, while WoS does not have these features. On the other hand, WoS has chemical structure search, but only a small number of publications are actually indexed for chemical structure searches. SciFinder

4012-493: The triad of main universal academic research databases. Journals in Scopus are reviewed for sufficient quality each year according to four numerical measures: h -Index , CiteScore , SJR ( SCImago Journal Rank ) and SNIP ( source normalized impact per paper ). For this reason, the journals listed in Scopus are considered to meet the requirement for peer review quality established by several research grant agencies for their grant recipients and by degree -accreditation boards in

4080-443: The years that followed, radioactivity was extensively investigated, notably by Marie Curie , a Polish physicist whose maiden name was Sklodowska, Pierre Curie , Ernest Rutherford and others. By the turn of the century, physicists had also discovered three types of radiation emanating from atoms, which they named alpha , beta , and gamma radiation. Experiments by Otto Hahn in 1911 and by James Chadwick in 1914 discovered that

4148-480: Was a particularly remarkable development since at that time fusion and thermonuclear energy, and even that stars are largely composed of hydrogen (see metallicity ), had not yet been discovered. The Rutherford model worked quite well until studies of nuclear spin were carried out by Franco Rasetti at the California Institute of Technology in 1929. By 1925 it was known that protons and electrons each had

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4216-439: Was actually due to a neutral particle of about the same mass as the proton, that he called the neutron (following a suggestion from Rutherford about the need for such a particle). In the same year Dmitri Ivanenko suggested that there were no electrons in the nucleus — only protons and neutrons — and that neutrons were spin 1 ⁄ 2 particles, which explained the mass not due to protons. The neutron spin immediately solved

4284-584: Was awarded jointly to Becquerel, for his discovery and to Marie and Pierre Curie for their subsequent research into radioactivity. Rutherford was awarded the Nobel Prize in Chemistry in 1908 for his "investigations into the disintegration of the elements and the chemistry of radioactive substances". In 1905, Albert Einstein formulated the idea of mass–energy equivalence . While the work on radioactivity by Becquerel and Marie Curie predates this, an explanation of

4352-408: Was performed during 1909, at the University of Manchester . Ernest Rutherford's assistant, Professor Johannes "Hans" Geiger, and an undergraduate, Marsden, performed an experiment in which Geiger and Marsden under Rutherford's supervision fired alpha particles ( helium 4 nuclei ) at a thin film of gold foil. The plum pudding model had predicted that the alpha particles should come out of

4420-463: Was published in 1909 by Geiger and Ernest Marsden , and further greatly expanded work was published in 1910 by Geiger . In 1911–1912 Rutherford went before the Royal Society to explain the experiments and propound the new theory of the atomic nucleus as we now understand it. Published in 1909, with the eventual classical analysis by Rutherford published May 1911, the key preemptive experiment

4488-512: Was remediated. Until 1990, the waste from the entire country of Yugoslavia was stored in Vinča. H2 also harbors the barrels with the depleted uranium and DU bullets, remnants of the ammunition collected on four locations in south Serbia after the 1999 NATO bombing of Serbia . In August 2002, a joint US-Russian mission removed 100 pounds of highly enriched uranium from the Vinča Nuclear Institute, to be flown to Russia . In 2009, it

4556-455: Was reported that the nuclear fuel storage pool, containing large quantities of radioactive waste , was in poor condition. In 2010, 2.5 tonnes of waste, including 13 kg of 80% highly enriched uranium, were transported from Vinča to a reprocessing facility at Mayak , Russia. This was the IAEA 's largest ever technical cooperation project, and thousands of police protected the convoys. Removal of

4624-495: Was surrounded by 7 more orbiting electrons. Around 1920, Arthur Eddington anticipated the discovery and mechanism of nuclear fusion processes in stars , in his paper The Internal Constitution of the Stars . At that time, the source of stellar energy was a complete mystery; Eddington correctly speculated that the source was fusion of hydrogen into helium, liberating enormous energy according to Einstein's equation E = mc . This

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