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51.
Jennifer E. Mihalick William P. Griffiths III James E. Muten Travis A. Olson John B. Hein 《Journal of solution chemistry》1999,28(8):1019-1030
Solution calorimetry was used to determine enthalpies and stability constants for binding of lead(II) or cadmium(II) by galacturonic acid and several monosaccharides in aqueous solution. New values for enthalpies of solution in water are reported for galacturonic acid and maltose monohydrate. The interaction of water solvent with the reactants is the largest factor in the binding process. 相似文献
52.
Per JensenSteven S. Wesolowski Nicole R. BrinkmannNancy A. Richardson Yukio YamaguchiHenry F. Schaefer III P.R. Bunker 《Journal of Molecular Spectroscopy》2002,211(2):254-261
The potential energy surface and dipole moment surfaces of the ã4A2 electronic state of CH2+ are calculated ab initio using an augmented correlation-consistent polarized valence quadruple-ζ (aug-cc-pVQZ) basis set, with the incorporation of dynamical correlation using the coupled cluster method with single and double excitations and perturbatively connected triple excitations [CCSD(T)]. We use these surfaces in the MORBID program system to calculate rotation and rotation-vibration term values for ã-state CH2+, CD+2, and CHD+ and to simulate the rotation and rotation-vibration absorption spectrum of CH2+ in the ã4A2 electronic state. Our work is motivated by studies of CH2+ that use the Coulomb explosion imaging technique and by the goal of predicting spectra that may be obtained from discharge sources. Although the ã state is the lowest-lying excited state above the X?/Ã ground state pair, it turns out to be relatively high-lying, and we determine that Te(ã)=30447.5 cm−1. The equilibrium bond angle for ã-state CH2+ is only 77.1°; as a result the asymmetric top κ value is close to 0, and the molecule is equally far from the oblate and prolate symmetric top limits in this electronic state. 相似文献
53.
Maryam I. Daneshvar Guillermo A. Casay Gabor Patonay Malgorzata Lipowska Lucjan Strekowski Lawrence Evans III Leila Tarazi Abraham George 《Journal of fluorescence》1996,6(2):69-75
The design and application of a fluorescent fiber-optic immunosensor (FFOI) are reported. The FFOI is utilized for the detection of antibody/antigen binding within the near-infrared (NIR) spectral region. The technique is developed through the combined use of fiber-optic, semiconductor laser-excitation, fluorescence detection, NIR dye, and immunochemical techniques. The antibody is immobilized on the FFOI and utilized as a recognition component for trace amounts of specific antigen. The FFOI is constructed to utilize an antibody sandwich technique. The assay involves the immobilization of the capture antibody on the sensing tip of the FFOI followed by the exposure of the immobilized sensing tip to the antigen. The antigen-coated FFOI is then introduced to a second antibody previously labeled with the NIR dye. Typical measurements are performed in about 15 min. A semiconductor laser provides the excitation (780 nm) of the immune complex. The resulting emission is detected by a silicon photodiode detector (820 nm). The intensity of the resulting fluorescence is directly proportional to the concentration of the antigen. The sensitivity of the analysis reaches 10 ng/ml and the response time is 10–15 min. 相似文献
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D. Korobkin Y.A. Urzhumov B. Neuner III C. Zorman Z. Zhang I.D. Mayergoyz G. Shvets 《Applied Physics A: Materials Science & Processing》2007,88(4):605-609
We theoretically and experimentally study electromagnetic properties of a novel mid-infrared metamaterial: optically thin
silicon carbide (SiC) membrane perforated by an array of sub-wavelength holes. Giant absorption and transmission is found
using Fourier transformed infrared (FTIR) microscopy and explained by introducing a frequency-dependent effective permittivity
εeff(ω) of the perforated film. The value of εeff(ω) is determined by the excitation of two distinct types of hole resonances: delocalized slow surface polaritons (SSPs) whose
frequencies are largely determined by the array period, and a localized surface polariton (LSP) corresponding to the resonance
of an isolated hole. Only SSPs are shown to modify εeff(ω) strongly enough to cause giant transmission and absorption. Because of the sub-wavelength period of the hole array, anomalous
optical properties can be directly traced to surface polaritons, and their interpretation is not obscured by diffractive effects.
Giant absorbance of this metamaterial can be utilized in designing highly efficient thermal radiation sources.
PACS 41.20.Cv; 42.70.Qs; 71.45.Gm 相似文献
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