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1.
We demonstrate the potential of femtosecond two-color pulse interferometry for in vitro optical glucose monitoring, by dispersion of the group refractive index in a glucose solution sample with respect to a red-color
light and a blue-color light. By comparison with femtosecond one-color pulse interferometry, the basic performance of the
present system with regard to sensitivity, quantitativeness, and tolerance to surrounding disturbances, is evaluated. The
resulting accuracy and precision of glucose determination are 77 and 118mg/dl for 10-mm-sample-thickness, respectively. This
near-common-path configuration of the two-color pulse light provides good stability to fluctuations of sample temperature,
which is important in clinical applications. Considering the performance of femtosecond two-color pulse interferometry as
an optical glucose sensor, a suitable measurement site for in vivo optical glucose monitoring is discussed. 相似文献
2.
3.
A wetting/dewetting process was utilized to prepare self-organized organic dye particles of micrometer and submicrometer size.
Near-field scanning optical microscopy successfully identified near-field excited near-field fluorescence from single particles.
The majority of the small particles with diameters around 2 mm or less, however, did not show fluorescence under near-field
observation. In contrast, far-field fluorescence, when excited by a polarized evanescent field, was observed, with the intensity
depending on the excitation polarization, indicating that molecules' transition moment within dye particles was oriented parallel
to the substrate surface. Single particle fluorescence spectrum consistently showed an identical sharp peak with a large redshift,
indicating that the particles were composed of identical dye aggregates similar to J-aggregates. These observations suggest
that the near-field at the probe tip was polarized parallel to the probe axis. Another observation, that molecules were oriented
in a similar direction among adjacent particles, suggests that the dewetting process contributed to the alignment of the molecular
direction among adjacent particles, which further proves that the present specimen was formed by a self-organizing mechanism. 相似文献
4.
Shindo M Yoshikawa T Itou Y Mori S Nishii T Shishido K 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,12(2):524-536
Ynolates were found to react with alpha-alkoxy-, alpha-siloxy-, and alpha-aryloxyketones at room temperature to afford tetrasubstituted olefins with high Z selectivity. Since the geometrical selectivity was determined in the ring opening of the beta-lactone enolate intermediates, the torquoselectivity was controlled by the ethereal oxygen atoms. From experimental and theoretical studies, the high Z selectivity is induced by orbital and steric interactions rather than by chelation. In a similar manner, alpha-dialkylamino ketones provided olefins with excellent Z selectivity. These products can be easily converted into multisubstituted butenolides and gamma-butyrolactams in good yield. 相似文献
5.
Photoinduced magnetization of the cyano-bridged 3d-4f heterobimetallic assembly Nd(DMF)4(H2O)3(mu-CN)Fe(CN)5.H2O (1) (DMF = N,N-dimethylformamide) is described in this paper. The chiMT values are enhanced by about 45% after UV light illumination in the temperature range of 5-50 K. We propose that UV light illumination induces a structural distortion in 1. This small structural change is propagated by molecular interactions in the inorganic network. Furthermore, the cooperativity resulting from the molecular interaction functions to increase the activation energy of the relaxation processes, which makes observation of the photoexcited state possible. The flexible network structure through the hydrogen bonds in 1 plays an essential role for the photoinduced phenomenon. This finding may open up a new domain for developing the molecule-based magnetic materials. 相似文献
6.
Some N-alkyl-naphthylazo pyridinium salts as new reagents for the spectrophotometric determination of anionic surfactants 总被引:1,自引:0,他引:1
Summary Eleven pyridinium azo dyes with straight-chain alkyl groups CnH2n+1–(n=6–18) and bromoalkyl groups BrCmH2m–(m=6–12) were synthesized with the intention of developing reagents for the determination of low levels of anionic surfactants in an aqueous medium. The effect of the alkyl chain length of these reagents on the reactivity with anionic surfactants such as sodium dodecylsulphate (SDS), sodium linear-dodecylbenzenesulphonate (DBS), sodium dodecylsulphonate (DS) and sodium laurate (SL) was studied. It was found that the alkyl chain length played an important role in the formation of ion associates and the composition of the ion associates formed. These reagents were classified into four groups with respect to the reactivity with anionic surfactants. The first group (n,m=6) reacts only with DBS. The second group (n,m=8) reacts with SDS, DBS and DS. The third group (n,m=10, 12) reacts with SDS, DBS and DS; however, the colour intensity of the DBS-ion associate was unstable. The fourth group (n=14, 16, 18) reacts with all anionic surfactants examined, and the composition of the ion associates with SDS and DS was 2:1 ([reagent]/[surfactant]) though that of the ion associates of the three reagent groups mentioned above was 1:1. The optimal conditions for the determination of anionic surfactants in river water with 1-octyl-4-(4-aminonaphthylazo)-pyridinium bromide was examined. The calibration graph was linear up to 3×10–6 mol/l, and the apparent molar absorptivity of the ion associate was 3.8×104 l mol–1 cm–1 (at 427 nm). The relative standard deviation for 2.4×10–6 mol/l SDS was 4.9%. Recoveries of 88–107% were found for 8.0×10–7 mol/l SDS in river water samples. 相似文献
7.
Motoki Okaniwa Naoyuki Kawashima Michitaka Kaizu Yasuaki Mutsuga 《Journal of polymer science. Part A, Polymer chemistry》2013,51(15):3132-3143
A new polymer blend composed of a hydrogenated ring‐opening polymer (HROP) with an ester group and hydroxyl functionalized polystyrene (HFP) produced the excellent transparent materials which enabled a precise birefringence control in keeping with the other physical properties for optical film use. The blend with a composition from 0.28 to 0.35 for the HFP weight fraction showed an extraordinary wavelength dispersion, transmitting through a zero birefringence point at the critical fraction of 0.45, while each polymer showed an ordinary wavelength dispersion. The observed excellent transparency even above those of the glass transition temperature was attributed to a depressed phase separation that resulted from strong hydrogen bond between the ester and hydroxyl groups. An IR analysis of the film demonstrated a remarkable red‐shift in the carbonyl peak with an increase of the hydroxylated polystyrene content, indicating a strong hydrogen bond between those groups. This new polymer blend provides a useful design to achieve practical demands for film use, both optical and mechanical under the fabrication conditions using the melt extrusion technique. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3132–3143 相似文献
8.
Applications of Clifford’s Geometric Algebra 总被引:1,自引:0,他引:1
We survey the development of Clifford’s geometric algebra and some of its engineering applications during the last 15 years. Several recently developed applications and their merits are discussed in some detail. We thus hope to clearly demonstrate the benefit of developing problem solutions in a unified framework for algebra and geometry with the widest possible scope: from quantum computing and electromagnetism to satellite navigation, from neural computing to camera geometry, image processing, robotics and beyond. 相似文献
9.
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