| 1. |
- Jones, R, et al.
(författare)
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Identification of the dominant nitrogen defect in silicon
- 1994
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 72:12, s. 1882-1885
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Tidskriftsartikel (refereegranskat)abstract
- The structure of the dominant N pair defect in Si is determined from channeling, infrared local vibrational mode spectroscopy, and ab initio local density functional theory. Channeling experiments show that the N atoms are displaced by 1.1±0.1 Å from lattice sites along 〈100〉. Annealing experiments reveal that this N site is associated with two N-related local vibrational modes originating from the N pair. The ab initio calculations demonstrate that the pair consists of two neighboring 〈100〉 oriented N-Si split interstitials, arranged in an antiparallel configuration, and with four N-Si bonds forming a square lying on {011}.
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| 2. |
- Linden, M, et al.
(författare)
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Airway inflammation in smokers with nonobstructive and obstructive chronic bronchitis
- 1993
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Ingår i: The American Review of Respiratory Disease. - 0003-0805. ; 148:5, s. 1226-1232
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Tidskriftsartikel (refereegranskat)abstract
- To assess the manifestation and location of airway inflammation in smokers with chronic bronchitis (CB) or chronic obstructive pulmonary disease (COPD), we lavaged the airways of 12 smokers with CB and 11 smokers with COPD and coexisting CB (OCB). For comparison, the airways of 5 asymptomatic smokers (AS) and 10 healthy nonsmokers (HNS) were lavaged. In all cases, the first lavage aliquot, labeled "bronchial lavage" (BL), was processed separately from the four subsequent aliquots, which were combined and labeled "bronchoalveolar lavage" (BAL). The composition of BL and BAL fluids indicate an ongoing inflammatory process in the airways of all three groups of smokers. CB patients with obstruction had significantly lower concentrations of inflammatory cells in the BL and BAL fluids compared with subjects with nonobstructed CB. Furthermore, airway obstruction, indicated by a reduced FEV1, was significantly correlated with the concentrations of glutathione (p < 0.001), myeloperoxidase (MPO; p < 0.01), and eosinophil cationic protein (ECP; p < 0.01) in BAL fluids. Taken together, these findings suggest that the manifestations of inflammation present in the airways of smokers with CB are different in those who have developed obstruction compared with those who have not.
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| 3. |
- Rasmussen, F Berg, et al.
(författare)
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Nitrogen in germanium : identification of the pair defect
- 1994
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Ingår i: Physical Review B Condensed Matter. - 0163-1829 .- 1095-3795. ; 50:7, s. 4378-4384
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Tidskriftsartikel (refereegranskat)abstract
- Several nitrogen-related centers have been introduced by ion implantation of nitrogen into germanium and studied by infrared-absorption spectroscopy. Two local vibrational modes at 825.3 and 658.6 cm-1 were especially prominent. Measurements on annealed samples implanted with either pure 14N or 15N, or implanted with both isotopes showed these modes to arise from a nitrogen pair defect analogous to one previously suggested to occur in silicon. Based on this and ab initio pseudopotential cluster theory, a model of the pair is proposed which is consistent with the observed infrared absorption. This model is similar to that of the nitrogen pair in silicon and offers an explanation of the low donor efficiency of nitrogen in germanium. Several other nitrogen-related local vibrational modes are also observed in the implanted material.
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| 4. |
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