| 1. |
- Anne, R., et al.
(författare)
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Dissociation Reactions of the Be-11 One-Neutron Halo - the Interplay between Structure and Reaction-Mechanism
- 1993
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Ingår i: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 0370-2693. ; 304:1-2, s. 55-59
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Tidskriftsartikel (refereegranskat)abstract
- The angular distributions of the forward neutrons in the exclusive (Be-10 + n) channel have been measured. They can be accounted for quantitatively and without free parameters in terms of Coulomb and diffraction dissociation. The results show that the transverse momentum distributions result from an interplay between the tail of the wave function (the halo) and the reaction mechanism.
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| 2. |
- Anne, R., et al.
(författare)
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Exclusive and Restricted-Inclusive Reactions Involving the Be-11 One-Neutron Halo
- 1994
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Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 575:1, s. 125-154
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Tidskriftsartikel (refereegranskat)abstract
- Reactions of a 41 MeV/u beam of the radioactive halo nucleus Be-11 have been studied with a counter telescope coupled to an array of neutron detectors covering angles up to 97-degrees. The technique allows to determine single-neutron inclusive and exclusive angular distributions. The targets (Be, Ti and Au) were chosen to illustrate the relative roles played by nuclear and Coulomb mechanisms. The channels leading to Be-10, the dissociation channels, correspond to impact parameters larger than the sum of the radii of the target and the Be-10 core. It is shown that for the dissociation process it is possible to account almost quantitatively for the integral, single- and double-differential cross sections from models without free parameters including the Coulomb, Serber and Glauber (diffraction-dissociation) mechanisms. The neutron distributions from the nondissociative reaction channels show little individuality and it is convenient to group them together as the channel ''neutron plus anything different from Be-10''. We refer to these as ''restricted-inclusive'' reactions. These seem to be a promising tool for obtaining accurate information on the halo wave function in momentum coordinates.
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| 3. |
- Borge, M. J. G., et al.
(författare)
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Beta-Decay to the Proton Halo State in F-17
- 1993
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Ingår i: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 317:1-2, s. 25-30
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Tidskriftsartikel (refereegranskat)abstract
- In the first experiment at the newly constructed ISOLDE Facility the first-forbidden beta-decay of Ne-17 into the first excited state of F-17 has been measured. It is a factor two faster than the corresponding mirror decay and thus gives one of the largest recorded asymmetries for beta decays feeding bound final states. Shell-model calculations can only reproduce the asymmetry if the halo structure of the F-17 state is taken into account.
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| 4. |
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| 5. |
- Rasmusson, A. G., et al.
(författare)
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Effect of calcium ions and inhibitors on internal NAD(P)H dehydrogenases in plant mitochondria
- 1991
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Ingår i: European Journal of Biochemistry. - : Wiley. - 0014-2956 .- 1432-1033. ; 202:2, s. 617-623
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Tidskriftsartikel (refereegranskat)abstract
- Both the external oxidation of NADH and NADPH in intact potato (Solanum tuberosum L. cv. Bintje) tuber mitochondria and the rotenone-insensitive internal oxidation of NADPH by inside-out submitochondrial particles were dependent on Ca2+. The stimulation was not due to increased permeability of the inner mitochondrial membrane. Neither the membrane potential nor the latencies of NAD+-dependent and NADP+-dependent malate dehydrogenases were affected by the addition of Ca2+. The pH dependence and kinetics of Ca2+-dependent NADPH oxidation by inside-out submitochondrial particles were studied using three different electron acceptors: O2, duroquinone and ferricyanide. Ca2+ increased the activity with all acceptors with a maximum at neutral pH and an additional minor peak at pH 5.8 with O2 and duroquinone. Without Ca2+, the activity was maximal around pH 6. The K(m) for NADPH was decreased fourfold with ferricyanide and duroquinone, and twofold with O2 as acceptor, upon addition of Ca2+. The V(max) was not changed with ferricyanide as acceptor, but increased twofold with both duroquinone and O2. Half-maximal stimulation of the NADPH oxidation was found at 3 μM free Ca2+ with both O2 and duroquinone as acceptors. This is the first report of a membrane-bound enzyme inside the inner mitochondrial membrane which is directly dependent on micromolar concentrations of Ca2+. Mersalyl and dicumarol, two potent inhibitors of the external NADH dehydrogenase in plant mitochondria, were found to inhibit internal rotenone-insensitive NAD(P)H oxidation, at the same concentrations and in manners very similar to their effects on the external NAD(P)H oxidation.
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| 6. |
- Rasmusson, A. G., et al.
(författare)
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Isolation of the rotenome-sensitive NADH-ubiquinone reductase (complex I) from red beet mitochondria
- 1994
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Ingår i: Physiologia Plantarum. - : Wiley. - 0031-9317 .- 1399-3054. ; 90:3, s. 607-615
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Tidskriftsartikel (refereegranskat)abstract
- Complex 1 of the respirator) chain (EC 1.6.531, measured as NADH-duroquinone and NADH-ubiquinone, reductase activities, was isolated from purified red beetroot (Beta vulgaris L.I mitochondria. The mitochondria were disrupted by freeze-thawing and inner membrane vesicles were pelleted. After solubilization of the vesicles with Triton X-100, the enzyme complex was purified 11-fold (compared to the activity in the inner membrane vesicles) by size-exclusion chromatography on a Sephacryl S-400 HR column and then by ion-exchange chromatography on a DEAE-Sepharose CL-6B column. Triton X-100 was present throughout the purification procedure. Tire purified complex showed approximately 30 bands on SDS-PAGE and about 15 polypeptides including those at 80. 54, 53. 51. 27. 25 and 22 kDa cross-reacted with polyclonal antibodies raised against complex I from Neurospora crassa. This is similar lo the pattern obtained with complex I from Neurospera crassa.Analysis by nativc-SDS 2-dimensional PAGE revealed the existence of several molecular mass forms of the purified complex.After reconstitution of the purified complex into phosphatidylcholine vesicles, the NADH-ubiquinone reductase activity had a Km (NADH) of about I μM and was inhibited by both rotenone and dicyclohexylcarbodiimide.
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| 7. |
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