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101.
Brian J. Larsen Robert J. Rosano Thomas A. Ford-Hutchinson Allen B. Reitz Jay E. Wrobel 《Tetrahedron》2018,74(22):2762-2768
The 1,3-indandione scaffold is an important structural motif used in the preparation of a large number of industrial chemical and pharmaceutical compounds. However, few approaches allow for the direct C2 acylation on these building blocks. A method was developed using DMAP and EDCI, which is mild in reactivity, covers a diverse range of carboxylic acid acylating agents, is compatible with electron releasing and withdrawing substituents on the 1,3-indandione partner, and performs well in a polar aprotic solvent (for solubility reasons) This method cleanly afforded twenty five different products in yields of 32–96%. 相似文献
102.
The circular dichroism of titanium‐doped silver chiral nanorod arrays grown using the glancing angle deposition (GLAD) method is investigated in the visible and near infrared ranges using transmission ellipsometry and spectroscopy. These films are found to have significant circular polarization effects across broad ranges of the visible to NIR spectrum, including large values for optical rotation. The characteristics of these circular polarization effects are strongly influenced by the morphology of the deposited arrays. Thus, the morphological control of the optical activity in these nanostructures demonstrates significant optimization capability of the GLAD technique for fabricating chiral plasmonic materials.
103.
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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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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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
110.