Institution
Stockholm University
Education•Stockholm, Sweden•
About: Stockholm University is a education organization based out in Stockholm, Sweden. It is known for research contribution in the topics: Population & Context (language use). The organization has 21052 authors who have published 62567 publications receiving 2725859 citations. The organization is also known as: University of Stockholm & Stockholms universitet.
Topics: Population, Context (language use), Galaxy, Supernova, Catalysis
Papers published on a yearly basis
Papers
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TL;DR: In this paper, the existence of ghost-free theories of massive spin-2 fields in both fixed and dynamical gravitational backgrounds was shown to be true for both non-linear and bimetric massive gravity theories.
Abstract: In massive gravity and in bimetric theories of gravity, two constraints are needed to eliminate the two phase-space degrees of freedom of the Boulware-Deser ghost. For recently proposed non-linear theories, a Hamiltonian constraint has been shown to exist and an associated secondary constraint was argued to arise as well. In this paper we explicitly demonstrate the existence of the secondary constraint. Thus the Boulware-Deser ghost is completely absent from these non-linear massive gravity theories and from the corresponding bimetric theories. Equivalently, this proves the existence of classically ghost-free theories of massive spin-2 fields, in both fixed and dynamical gravitational backgrounds.
503 citations
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TL;DR: It was discovered later that the spent catalyst of an acetaldehyde reactor, which caused the pollution, contained approximately 1 per cent methyl mercury; and the biological methylation of mercury was thought to be insignificant.
Abstract: THERE have been incidences of extensive alkyl-mercury poisoning in Japan and Sweden. In Japan a large number of people belonging to the fishing population around Minamata Bay were seriously affected by what is now called Minamata disease. This incident was traced back to pollution of the bay with the mercury containing effluent of a large chemical plant. When methyl thiomethyl-mercury was isolated from shellfish in the area of the bay it was suggested that mercury could be alkylated by “plankton and other marine life”2. It was discovered later that the spent catalyst of an acetaldehyde reactor, which caused the pollution, contained approximately 1 per cent methyl mercury; and the biological methylation of mercury was thought to be insignificant.
502 citations
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TL;DR: Evidence that black carbon may strongly reduce the risk posed by organic contaminants in sediments and soils is reviewed, implying that current environmental risk assessment systems for these contaminants may be unnecessarily safe.
502 citations
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CERN1, Goethe University Frankfurt2, Helsinki Institute of Physics3, University of Helsinki4, University of Leeds5, Paul Scherrer Institute6, University of Washington7, University of Innsbruck8, University of Lisbon9, ETH Zurich10, California Institute of Technology11, University of Eastern Finland12, Finnish Meteorological Institute13, Lebedev Physical Institute14, Stockholm University15, University of Vienna16, Leibniz Association17, University of Beira Interior18, Carnegie Mellon University19
TL;DR: Ion-induced nucleation of pure organic particles constitutes a potentially widespread source of aerosol particles in terrestrial environments with low sulfuric acid pollution.
Abstract: Atmospheric aerosols and their effect on clouds are thought to be important for anthropogenic radiative forcing of the climate, yet remain poorly understood. Globally, around half of cloud condensation nuclei originate from nucleation of atmospheric vapours. It is thought that sulfuric acid is essential to initiate most particle formation in the atmosphere, and that ions have a relatively minor role. Some laboratory studies, however, have reported organic particle formation without the intentional addition of sulfuric acid, although contamination could not be excluded. Here we present evidence for the formation of aerosol particles from highly oxidized biogenic vapours in the absence of sulfuric acid in a large chamber under atmospheric conditions. The highly oxygenated molecules (HOMs) are produced by ozonolysis of α-pinene. We find that ions from Galactic cosmic rays increase the nucleation rate by one to two orders of magnitude compared with neutral nucleation. Our experimental findings are supported by quantum chemical calculations of the cluster binding energies of representative HOMs. Ion-induced nucleation of pure organic particles constitutes a potentially widespread source of aerosol particles in terrestrial environments with low sulfuric acid pollution.
502 citations
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Danish Space Research Institute1, National Space Institute2, University of Helsinki3, ENEA4, University of Ferrara5, University of Valencia6, Stockholm University7, Spanish National Research Council8, Alenia Aeronautica9, Bosch10, European Space Research and Technology Centre11, Max Planck Society12, Harvard University13
TL;DR: The JEM-X monitor as discussed by the authors provides X-ray spectra and imaging with arcminute angular resolution in the 3 to 35 keV band with an angular resolution of 3 0 across an eective field of view of about 10 diameter.
Abstract: The JEM-X monitor provides X-ray spectra and imaging with arcminute angular resolution in the 3 to 35 keV band. The good angular resolution and the low energy response of JEM-X plays an important role in the identification of gamma ray sources and in the analysis and scientific interpretation of the combined X-ray and gamma ray data. JEM-X is a coded aperture instrument consisting of two identical, coaligned telescopes. Each of the detectors has a sensitive area of 500 cm 2 , and views the sky through its own coded aperture mask. The two coded masks are inverted with respect to each other and provides an angular resolution of 3 0 across an eective field of view of about 10 diameter.
501 citations
Authors
Showing all 21326 results
Name | H-index | Papers | Citations |
---|---|---|---|
Hongjie Dai | 197 | 570 | 182579 |
Hyun-Chul Kim | 176 | 4076 | 183227 |
Richard S. Ellis | 169 | 882 | 136011 |
Stanley B. Prusiner | 168 | 745 | 97528 |
Anders Björklund | 165 | 769 | 84268 |
Yang Yang | 164 | 2704 | 144071 |
Tomas Hökfelt | 158 | 1033 | 95979 |
Bengt Winblad | 153 | 1240 | 101064 |
Zhenwei Yang | 150 | 956 | 109344 |
Marvin Johnson | 149 | 1827 | 119520 |
Jan-Åke Gustafsson | 147 | 1058 | 98804 |
Markus Ackermann | 146 | 610 | 71071 |
Hans-Olov Adami | 145 | 908 | 83473 |
Markku Kulmala | 142 | 1487 | 85179 |
Kjell Fuxe | 142 | 1479 | 89846 |