1. |
- Persson, Bertil R, et al.
(författare)
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Radioactivity exploration from the Arctic to the Antarctic. Part 3. The SWEDARP expedition Oct 1988 – April 1989
- 2015
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Ingår i: Acta Scientiarum Lundensia. - 1651-5013. ; 2015:004, s. 1-17
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Tidskriftsartikel (refereegranskat)abstract
- The Swedish Antarctic Research Expedition named “SWEDARP” was performed during October 1988 through April 1989. The aim of our project was to study the radioactivity in air and water from Gothenburg to the Antarctic. Between Gothenburg and the Equator, the average activity concentration of 7Be in air was 4.3 ± 0.7 mBq/m3. The activity concentration of 7Be in the South Atlantic down to Antarctica varied between 1.3 and 1.7 with an average of 1.5 ± 0.8 mBq/m3. The average activity concentration of 210Pb in air during autumn 1988 on the route Gothenburg- Montevideo was about 290±270 micro-Bq/m3 and on the return in spring 1989 it was about 230±140 micro-Bq/m3. At the Equator, the average activity concentration of 210Pb in November 1988 was about 630±170 and in April 1989 about 260±210 microBq/m3. In the South Atlantic down to Antarctica during February-March 1989, the activity concentration of 210Pb varied between 11 and 58 micro-Bq/m3. The average activity concentration of 210Po in air during the route Gothenburg- Montevideo in 1988 was about 63±58, and on the return, it was about 60±44 The Swedish Antarctic Research Expedition named “SWEDARP” was performed during October 1988 through April 1989. The aim of our project was to study the radioactivity in air and water from Gothenburg to the Antarctic. Between Gothenburg and the Equator, the average activity concentration of 7Be in air was 4.3 ± 0.7 mBq/m3. The activity concentration of 7Be in the South Atlantic down to Antarctica varied between 1.3 and 1.7 with an average of 1.5 ± 0.8 mBq/m3. The average activity concentration of 210Pb in air during autumn 1988 on the route Gothenburg- Montevideo was about 290±270 micro-Bq/m3 and on the return in spring 1989 it was about 230±140 micro-Bq/m3. At the Equator, the average activity concentration of 210Pb in November 1988 was about 630±170 and in April 1989 about 260±210 microBq/m3. In the South Atlantic down to Antarctica during February-March 1989, the activity concentration of 210Pb varied between 11 and 58 micro-Bq/m3. The average activity concentration of 210Po in air during the route Gothenburg- Montevideo in 1988 was about 63±58, and on the return, it was about 60±44 micro-Bq/m3. At the Equator, the average activity concentration in Nov 1988 was about 132±45, and in April 1989 about 70±60 micro-Bq/m3. The activity concentration of 210Po in the South Atlantic down to Antarctica during February-March 1989 varied between 6 and 14 micro-Bq/m3. The inventory (Bq.m-2) of various deposited ratio nuclides, measured in moss, lichen, soil and lake sediments was: 280 ±110 for 210Pb (excess); 155 ± 95 for 137Cs, 4.6 ± 2.6 for 239+240Pu, 1.6 ± 1.0 for 241Am and, 0.95± 0.5 for 238Pu. 137Cs activity concentration (Bq.m-3) in surface waters samples along the route of the SWEDARP expedition was about 3 Bq.m-3 above 20 °N , decreased to about 2 Bq.m-3 between 20 °N and 40 °S where it decrease to about 1 Bq.m-3 , and at 55 °S (e) there is a further decrease to about 0.3 Bq.m-3. Radio-Caesium, which originates from atmospheric nuclear weapons tests carried out in the late 1950's and the early 1960's shows a long residence time in surface waters of the North and South Atlantic Oceans with half-time, corrected for physical decay estimated to be more than bout 100 years. Concentration factor for 137Cs estimated to 15000 for fish in the Antarctic is much higher than the value of 500 given by The IAEA 1985. Concentration factors for MacroAlgea/Water, was found to be about 1800 in the Antarctic compared to 100 the Arctic. The 239+240Pu activity concentrations in the surface water was about 8 mBq.m-3 in the latitude band 5°-25 °N , about 3 mBq.m-3 in the latitude band 25-5 °N; and about 1,5 mBq.m-3 in the latitude band 0 °S-60 °S. Plutonlum-238 activity was measured in a few water samples from the southern hemisphere with activity ratio of 238Pu to 239+240Pu in the range of 0.14-0.22. Plutonium isotopes 239+240Pu from atmospheric nuclear weapons tests has a low half-life of 7-8 years due to the higher affinity to sinking particles for Pu than Cs. In the southern hemisphere, 238Pu was found as the result of the 1964 burn-up of a satellite in the atmosphere over the Mozambique Channel. The Average activity concentrations (Bq/kgdw,) of 137Cs are in flesh of seals 2.5, penguins 0.2 and, fish 2.5 in liver of seals 0.6 and penguins 0.7 and in kidneys of seals 0.5. The Average activity concentrations (Bq/kgdw) of 210Po are in flesh of seals 8, penguins 4 and, fish 7, in liver of seals 110 and penguins 43 and, fish 5, and in kidneys of seals 91 and of penguins 43. The Average activity concentrations (Bq/kgdw,) of 210Pb are in flesh of seals 0,3, penguins 0,2, and fish 0.6, in liver of seals 4 and penguins 1 and, fish 1, and in kidneys of seals 1 and of penguins 1. The Average activity concentration of 137Cs in samples of Krill is about 1.7 Bq/kgdw of 210Po and 210Pb are in samples of Amphipods, 87 and 1.4 Bq/kgdw respectively. Radio-Caesium, which originates from atmospheric nuclear weapons tests carried out in the late 1950's and the early 1960's shows a long residence time in surface waters of the North and South Atlantic Oceans with half-time, corrected for physical decay estimated to be more than bout 100 years. Plutonium isotopes 239+240Pu from atmospheric nuclear weapons tests has a low half-life of 7-8 years due to the higher affinity to sinking particles for Pu than Cs. In the southern hemisphere, 238Pu was found as the result of the 1964 burn-up of a satellite in the atmosphere over the Mozambique Channel.Bq/m3. At the Equator, the average activity concentration in Nov 1988 was about 132±45, and in April 1989 about 70±60 micro-Bq/m3. The activity concentration of 210Po in the South Atlantic down to Antarctica during February-March 1989 varied between 6 and 14 micro-Bq/m3. The inventory (Bq.m-2) of various deposited ratio nuclides, measured in moss, lichen, soil and lake sediments was: 280 ±110 for 210Pb (excess); 155 ± 95 for 137Cs, 4.6 ± 2.6 for 239+240Pu, 1.6 ± 1.0 for 241Am and, 0.95± 0.5 for 238Pu. 137Cs activity concentration (Bq.m-3) in surface waters samples along the route of the SWEDARP expedition was about 3 Bq.m-3 above 20 °N , decreased to about 2 Bq.m-3 between 20 °N and 40 °S where it decrease to about 1 Bq.m-3 , and at 55 °S (e) there is a further decrease to about 0.3 Bq.m-3. Radio-Caesium, which originates from atmospheric nuclear weapons tests carried out in the late 1950's and the early 1960's shows a long residence time in surface waters of the North and South Atlantic Oceans with half-time, corrected for physical decay estimated to be more than bout 100 years. Concentration factor for 137Cs estimated to 15000 for fish in the Antarctic is much higher than the value of 500 given by The IAEA 1985. Concentration factors for MacroAlgea/Water, was found to be about 1800 in the Antarctic compared to 100 the Arctic. The 239+240Pu activity concentrations in the surface water was about 8 mBq.m-3 in the latitude band 5°-25 °N , about 3 mBq.m-3 in the latitude band 25-5 °N; and about 1,5 mBq.m-3 in the latitude band 0 °S-60 °S. Plutonlum-238 activity was measured in a few water samples from the southern hemisphere with activity ratio of 238Pu to 239+240Pu in the range of 0.14-0.22. Plutonium isotopes 239+240Pu from atmospheric nuclear weapons tests has a low half-life of 7-8 years due to the higher affinity to sinking particles for Pu than Cs. In the southern hemisphere, 238Pu was found as the result of the 1964 burn-up of a satellite in the atmosphere over the Mozambique Channel. The Average activity concentrations (Bq/kgdw,) of 137Cs are in flesh of seals 2.5, penguins 0.2 and, fish 2.5 in liver of seals 0.6 and penguins 0.7 and in kidneys of seals 0.5. The Average activity concentrations (Bq/kgdw) of 210Po are in flesh of seals 8, penguins 4 and, fish 7, in liver of seals 110 and penguins 43 and, fish 5, and in kidneys of seals 91 and of penguins 43. The Average activity concentrations (Bq/kgdw,) of 210Pb are in flesh of seals 0,3, penguins 0,2, and fish 0.6, in liver of seals 4 and penguins 1 and, fish 1, and in kidneys of seals 1 and of penguins 1. The Average activity concentration of 137Cs in samples of Krill is about 1.7 Bq/kgdw of 210Po and 210Pb are in samples of Amphipods, 87 and 1.4 Bq/kgdw respectively. Radio-Caesium, which originates from atmospheric nuclear weapons tests carried out in the late 1950's and the early 1960's shows a long residence time in surface waters of the North and South Atlantic Oceans with half-time, corrected for physical decay estimated to be more than bout 100 years. Plutonium isotopes 239+240Pu from atmospheric nuclear weapons tests has a low half-life of 7-8 years due to the higher affinity to sinking particles for Pu than Cs. In the southern hemisphere, 238Pu was found as the result of the 1964 burn-up of a satellite in the atmosphere over the Mozambique Channel.
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2. |
- Aquilante, Francesco, et al.
(författare)
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Software news and update MOLCAS 7 : The Next Generation
- 2010
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Ingår i: Journal of Computational Chemistry. - : Wiley. - 0192-8651 .- 1096-987X. ; 31:1, s. 224-247
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Forskningsöversikt (refereegranskat)abstract
- Some of the new unique features of the MOLCAS quantum chemistry package version 7 are presented in this report. In particular, the Cholesky decomposition method applied to some quantum chemical methods is described. This approach is used both in the context of a straight forward approximation of the two-electron integrals and in the generation of so-called auxiliary basis sets. The article describes how the method is implemented for most known wave functions models: self-consistent field, density functional theory, 2nd order perturbation theory, complete-active space self-consistent field multiconfigurational reference 2nd order perturbation theory, and coupled-cluster methods. The report further elaborates on the implementation of a restricted-active space self-consistent field reference function in conjunction with 2nd order perturbation theory. The average atomic natural orbital basis for relativistic calculations, covering the whole periodic table, are described and associated unique properties are demonstrated. Furthermore, the use of the arbitrary order Douglas-Kroll-Hess transformation for one-component relativistic calculations and its implementation are discussed. This section especially focuses on the implementation of the so-called picture-change-free atomic orbital property integrals. Moreover, the ElectroStatic Potential Fitted scheme, a version of a quantum mechanics/molecular mechanics hybrid method implemented in MOLCAS, is described and discussed. Finally, the report discusses the use of the MOLCAS package for advanced studies of photo chemical phenomena and the usefulness of the algorithms for constrained geometry optimization in MOLCAS in association with such studies.
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3. |
- Guehne, Otfried, et al.
(författare)
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Compatibility and noncontextuality for sequential measurements
- 2010
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Ingår i: PHYSICAL REVIEW A. - 1050-2947. ; 81:2, s. 022121-
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Tidskriftsartikel (refereegranskat)abstract
- A basic assumption behind the inequalities used for testing noncontextual hidden variable models is that the observables measured on the same individual system are perfectly compatible. However, compatibility is not perfect in actual experiments using sequential measurements. We discuss the resulting "compatibility loophole" and present several methods to rule out certain hidden variable models that obey a kind of extended noncontextuality. Finally, we present a detailed analysis of experimental imperfections in a recent trapped-ion experiment and apply our analysis to that case.
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4. |
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5. |
- Persson, Bertil R, et al.
(författare)
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Radioactivity exploration from the Arctic to the Antarctic. Part 4: The Arctic Ocean-91 expedition
- 2015
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Ingår i: Acta Scientiarum Lundensia. - 1651-5013. ; 2015:005, s. 1-14
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Tidskriftsartikel (refereegranskat)abstract
- The Arctic Ocean expedition in 1991 with the Swedish icebreaker M/S Oden was focused on oceanography and geology. The aim of our project was exploring the activity concentrations in surface air of 7Be, 210Pb. and 210Po in the surface air, radioactive isotopes of Caesium (134Cs, 137Cs) and plutonium (239+240Pu) in seawater. During the cruise in the Arctic Ocean during 1991-07-28 to 1991-10-04 the average activity concentrations in surface air of 7Be was 0.6±0.4 mBq.m-3 , 210Pb 46±34 microBq.m-3 and 210Po 37±23 microBq.m-3 The activity concentration of 137Cs in the surface of the Arctic Ocean was in the range of 8-12 Bq.m-3. When crossing the Nansen basin the activity concentration of 137Cs increased to about 18 Bq.m-3 at 88 °N 80 °E, and there was an accumulation of 137Cs in an area around at 88 °N and 80-100 °E and locally increased activity at 83 °N 10 °E. The 134Cs/137Cs activity ratios was about 0.02 due to the contribution mainly from Sellafield and a few percent contribution from Chernobyl. The 134Cs/137Cs activity ratio decreased to about 0.002-0.005 in areas of high 137Cs activity concentration which exclude contribution of 134Cs of nuclear reactor fuel. The activity concentration of 239+240Pu in the surface of the Arctic Ocean was in the range of 6 - 8 mBq.m-3. But locally the activity concentration of 239+240Pu was found to be increased to 11 mBq.m-3 at 86°N 48-53°E, and to 16 mBq.m-3 at 83°N 10°E.
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6. |
- Persson, Bertil R, et al.
(författare)
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Radioactivity Exploration from the Arctic to the Antarctic. Part 6: The Arctic Ocean-96 expedition
- 2015
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Ingår i: Acta Scientiarum Lundensia. - 1651-5013. ; 2015:007, s. 1-22
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Tidskriftsartikel (refereegranskat)abstract
- The Swedish Arctic Ocean-96 expedition arranged by the Swedish Polar Research Committee took place during 1996 with the Swedish icebreaker M/S Oden. The expedition focused on studying the distribution of radionuclides in different water masses in the central Arctic Ocean. The expedition crossed the Barents Sea, entered the Nansen Basin at the St. Anna Trough, and continued north across the Amundsen Basin. The main part of the expedition was concentrated on the north Lomonosov Ridge and the return route passed the North Pole and went south along 10 oE towards Svalbard. In both legs, water samples in the surface and subsurface layers were collected for the determination of fission products and transuranic elements in seawater and sediment. The highest 137Cs, 90Sr and 129l activities and 134Cs/137Cs activity ratios are found in a band stretching from the northern Lomonosov Ridge, over the North Pole and south along 10-15 oE to 85 oN. The releases from European nuclear fuel reprocessing plants and Chernobyl fallout traced by the 129I and 134Cs/137Cs signals respectively have approximately the same spatial distribution in the Arctic Ocean surface layer. The activity concentration of 90Sr in surface water is about 2 Bq.m-3. For 239+240Pu the lowest concentrations in the surface water of 4 mBq.m-3 was found on the Lomonosov Ridge and in the Makarov Basin. In the Eurasian Basin, the concentrations 239+240Pu are about 13 mBq.m-3 . For all the radionuclides analysed, the water profiles generally show activities decreasing with depth. An exception is the high 137Cs activity concentrations found in the lower halocline layer at the Lomonosov Ridge and Makarov Basin stations. The maxima were not observed in the 90Sr or l29l measurements. It is assumed to be due to a contribution of Chernobyl fallout to the Arctic Ocean surface layers in the years around 1990. Inventories down to 900 m death reveal that between 60-70 % of the 137Cs, 90Sr and in the Arctic Ocean water, are present in the surface layer inflow from the Atlantic. The total inventories down to 900 m in the Eurasian Basin of the Arctic Ocean estimate to 6.7 PBq for 137Cs, 3.4 PBq for 90Sr and 5.3x1028 atoms for 129l.
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7. |
- Shami, Annelie, et al.
(författare)
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Fibromodulin Deficiency Reduces Low-Density Lipoprotein Accumulation in Atherosclerotic Plaques in Apolipoprotein E-Null Mice.
- 2012
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Ingår i: Arteriosclerosis, Thrombosis and Vascular Biology. - 1524-4636.
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: The aim of this study was to analyze how an altered collagen structure affects development of atherosclerotic plaques. METHODS AND RESULTS: Fibromodulin-null mice develop an abnormal collagen fibril structure. In apolipoprotein E (ApoE)-null and ApoE/fibromodulin-null mice, a shear stress-modifying carotid artery cast induced formation of atherosclerotic plaques of different phenotypes; inflammatory in low-shear stress regions and fibrous in oscillatory shear stress regions. Electron microscopy showed that collagen fibrils were thicker and more heterogeneous in oscillatory shear stress lesions from ApoE/fibromodulin-null mice. Low-shear stress lesions were smaller in ApoE/fibromodulin-null mice and contained less lipids. Total plaque burden in aortas stained en face with Oil Red O, as well as lipid accumulation in aortic root lesions, was also decreased in ApoE/fibromodulin-null mice. In addition, lipid accumulation in RAW264.7 macrophages cultured on fibromodulin-deficient extracellular matrix was decreased, whereas levels of interleukin-6 and -10 were increased. Our results show that an abnormal plaque collagen fibril structure can influence atherosclerotic plaque development. CONCLUSIONS: The present findings suggest a more complex role for collagen in plaque stability than previously anticipated, in that it may promote lipid-accumulation and inflammation at the same time as it provides mechanical stability.
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8. |
- Svenson, Ulrika, et al.
(författare)
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Telomere length in peripheral leukocytes is associated with immune cell tumor infiltration and prognosis in colorectal cancer patients
- 2016
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Ingår i: Tumor Biology. - : Springer Science and Business Media LLC. - 1010-4283 .- 1423-0380. ; 37:8, s. 10877-10882
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Tidskriftsartikel (refereegranskat)abstract
- Telomeres are protective structures at the end of chromosomes, essential for chromosomal integrity. A large number of studies have investigated leukocyte telomere length as a possible risk marker for various cancers, colorectal cancer (CRC) included. In contrast, studies investigating leukocyte telomere length in relation to CRC survival are lacking. We previously reported that relative telomere length (RTL) of leukocytes collected at diagnosis predicted survival in patients with breast and kidney cancer. We suggested that these findings might reflect various immunological mechanisms, affected by the presence of a tumor. In the present study, leukocyte RTL was examined in relation to immune cell tumor infiltration and prognosis in 130 patients with CRC diagnosis. RTL was measured with a well-established qPCR method. We found that patients with the highest degree of lymphocyte tumor infiltration had shorter leukocyte RTL. Consistent with our previous findings, short RTL was a favorable prognostic marker in univariate survival analysis. In the current study, RTL did not remain as an independent predictor in multivariate survival analysis, when including metastatic status in the model. However, a non-significant trend towards a similar telomere-associated survival pattern was observed in patients with limited disease. In contrast, for patients who died of other causes than CRC, short RTL was associated with significantly shorter survival time. To our knowledge, this is the first study to investigate an association between leukocyte RTL, immune cell tumor infiltration, and cancer-specific survival in CRC patients. Larger studies are warranted to verify these findings.
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9. |
- Veryazov, Valera, et al.
(författare)
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How to Select Active Space for Multiconfigurational Quantum Chemistry?
- 2011
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Ingår i: International Journal of Quantum Chemistry. - : Wiley. - 0020-7608. ; 111:13, s. 3329-3338
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Tidskriftsartikel (refereegranskat)abstract
- Bjorn Roos is one of the pioneers in the development and usage of multiconfigurational methods, in particular, the complete active space self-consistent field method and the perturbational complete active space perturbation theory through second order. To perform multiconfigurational calculations using these methods, a set of active orbitals must be selected, and the success of the methods depends on the choice of this set. This is not only sometimes easy but also sometimes difficult, especially for use of the more recent RASSCF and RASPT2 methods (which use a "restricted active space" rather than the complete one). Although an automated procedure for selecting the active orbitals would be a preferable solution, this does not seem feasible yet. An account of the problem is given, with examples and some approaches that usually work. (C) 2011 Wiley Periodicals, Inc. Int J Quantum Chem 111: 3329-3338, 2011
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10. |
- Wang, Xuefeng, et al.
(författare)
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Infrared Spectra and Quantum Chemical Calculations of the Uranium Carbide Molecules UC and CUC with Triple Bonds.
- 2010
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Ingår i: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 1520-5126 .- 0002-7863. ; 132, s. 8484-8488
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Tidskriftsartikel (refereegranskat)abstract
- Laser evaporation of carbon-rich uranium/carbon alloys followed by atom reactions in a solid argon matrix and trapping at 8 K gives weak infrared absorptions for CUO at 852 and 804 cm−1. A new band at 827 cm−1 becomes a doublet with mixed carbon 12 and 13 isotopes and exhibits the 1.0381 isotopic frequency ratio, which is appropriate for the UC diatomic molecule, and another new band at 891 cm−1 gives a three-band mixed isotopic spectrum with the 1.0366 isotopic frequency ratio, which is characteristic of the linear CUC molecule. CASPT2 calculations with dynamical correlation find the C≡U≡C ground state as linear 3Σu+ with 1.840 Å bond length and molecular orbital occupancies for an effective bond order of 2.83. Similar calculations with spin-orbit coupling show that the U≡C diatomic molecule has a quintet (Λ = 5, Ω = 3) ground state, a similar 1.855 Å bond length, and a fully developed triple bond of 2.82 effective bond order.
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