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101.
Richard K. PhippsCharlotte H. Gotfredsen Søren R. PaludanJens C. Frisvad Kathrine EriksenBent O. Petersen Jens Ø. DuusThomas O. Larsen 《Tetrahedron letters》2011,52(5):598-601
Six new meroterpenoid compounds, hesseltins B-G, were isolated from Penicillium species along with the previously described hesseltin A. A further 14 compounds, which turned out to be photoisomers, were detected during purification and were subsequently isolated. The structures of these analogues were elucidated by comparison of their NMR spectral data with that of hesseltin A. None of the new hesseltins showed antiviral activity in a Herpes simplex virus type 2 assay. 相似文献
102.
Ravi Jasuja Theodore L. Hazlett Michael K. Helms Suk-Hyung Lee David M. Jameson Randy W. Larsen 《Chemical physics letters》2001,350(5-6):515-521
In the current report, the temperature dependence of photoinduced electron transfer between tetrakis-(4-tetramethylpyridyl)porphine (T4MPyP) and guanine monophosphate (GMP) has been examined. In the presence of GMP the fluorescence lifetime analysis reveals a Lorentzian distribution of lifetimes centered at 0.7 ns with a width of 0.9 ns displaying significant temperature dependence. Fitting temperature dependent data to the Marcus equation gives a reorganizational energy (λ) for the electron transfer reaction of 0.6 eV and an electronic coupling factor (HAB) of 3×10−3 eV. These results suggest conformational regulation of electron transfer within the non-covalent porphyrin:nucleotide complex. 相似文献
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105.
Mike Larsen 《CHANCE》2009,22(2):43-45
The graphics contest announced in Volume 23, Issue 4, of CHANCE asked readers to create a display of a 1951 data set on antibiotic effectiveness. The three winners of the contest are Mark
Nicolich, Brian Schmotzer, and Dibyojyoti Haldar. The winners’ graphs are different, yet communicate the same information—each
compares the antibiotics and bacteria and succinctly summarizes the influence of the gram staining factor. 相似文献
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108.
T.P. Leervad Pedersen J. Skov Jensen J. Chevallier O. Hansen J.M. Jensen B. Bech Nielsen A. Nylandsted Larsen 《Applied Physics A: Materials Science & Processing》2005,81(8):1591-1593
The synthesis of evenly distributed Ge nanoclusters in plasma-enhanced chemical-vapour-deposited (PE-CVD) SiO2 thin films containing 8 at. % Ge is reported. This is of importance for the application of nanoclusters in semiconductor
technology. The average diameter of the Ge nanoclusters can be controlled in the range of 3–6 nm by variation of the annealing
parameters. Using a combination of transmission electron microscopy and Raman-scattering spectroscopy, the nanoclusters were
shown to be crystalline. However, photoluminescence measurements showed no light emission that could be definitively correlated
to the presence of the nanoclusters.
PACS 61.82.Rx; 78.67.Bf; 81.07.Bc 相似文献
109.
N.R. Zangenberg J. Chevallier J.L. Hansen A Nylandsted Larsen 《Applied Physics A: Materials Science & Processing》2005,81(5):1077-1082
The effect of surface capping on the super- and undersaturation of point defects in Si has been investigated by the diffusion of deep (400 nm) and shallow (200 nm) high concentration profiles of boron grown by molecular beam epitaxy (MBE). Additional information is extracted from the self-diffusion of Ge in the Si-like Si0.50Ge0.50-matrix. The objective is to investigate the injection of vacancies and interstitials from surface or bulk with the aim of obtaining inert diffusion conditions . PACS 61.72.Ji; 66.30.-h; 68.55.Ln; 68.35.Dv; 81.65.-b 相似文献
110.