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51.
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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We investigate when the set of finite products of distinct terms of a sequence 〈x
n
〉
n=1∞ in a semigroup (S,⋅) is large in any of several standard notions of largeness. These include piecewise syndetic, central, syndetic, central*, and IP*. In the case of a “nice” sequence in (S,⋅)=(ℕ,+) one has that FS(〈x
n
〉
n=1∞) has any or all of the first three properties if and only if {x
n+1−∑
t=1
n
x
t
:n∈ℕ} is bounded from above.
N. Hindman acknowledges support received from the National Science Foundation via Grant DMS-0554803. 相似文献
60.
Cavin III Ralph K. Herr Daniel J.C. Zhirnov Victor V. 《Journal of nanoparticle research》2000,2(3):213-235
The purpose of this paper is to identify areas in the basic physical sciences where additional research is needed to sustain the extraordinary progress in electronics that has now extended for several decades. Also, it is argued that basic research will provide the foundation for the discovery of new generations of nanoelectronic devices that will continue the experimental rate of reduction in cost per function. Some of the fundamental areas requiring further research are the chemistry and physics of material interfaces, conductivity at small dimensions, deterministic doping effects, and nanomagnetics. Discovery research also is needed in the functional synergy of nanoelectronic materials and non-traditional fabrication methods. 相似文献