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31.
A novel biosensor harnessing a peptide layer which has specific affinity to lead ion proved to be highly effective for electrochemical analysis of lead ions. The peptide modified electrode was used for the electrochemical analysis of various trace metal ions by square wave voltammetry. Compared to the other ions investigated, the peptide modified electrode was found to be highly selective to Pb2+ in the range of 50–700 nM. Furthermore, the biosensor exhibited a high reusability and good spike recovery in the tap water containing various concentration of Pb2+. 相似文献
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33.
The microwave spectrum of cyanocyclopentane has been observed and analyzed in the 26.5 to 40.0-GHz frequency region. Rotational transitions were assigned for both an axial and an equatorial conformer. These data and those for the molecule deuterated in the 1-position (1-d-cyanocyclopentane) show that both conformers adopt the Cs envelope structure. For the normal isotopic species the rotational constants have the following values, in megahertz: axial, A = 4297.196, B = 2210.245, C = 2057.205; equatorial, A = 6324.905, B = 1790.937, C = 1497.792. Relative intensity measurements indicate that the ground-state energy difference of the two conformers is 0 ± 200 cal/mole. The low-frequency (pseudorotational) potential surface has been discussed and compared with that of chlorocyclopentane. 相似文献
34.
T. Tipton J.-I. Choe S.G. Kukolich R. Hubbard 《Journal of Molecular Spectroscopy》1985,114(2):239-256
Fourier transform spectra covering the range from 1500 to 5400 cm?1 with 0.02-cm?1 resolution have been obtained for formaldehyde. A study of the region above 4000 cm?1 has yielded rotational constants and other asymmetric rotor parameters for three bands: 3ν2 (ν0 = 5177.7611 ± 0.0005 cm?1)2ν2 + ν6 (ν0 = 4734.193 ± 0.004 cm?1), and ν3 + ν5 (ν0 = 4335.102 ± 0.001 cm?1). An analysis of the A-type Coriolis interaction between the 2ν2 + ν6 state and the unobserved 2ν2 + ν4 state has yielded partially deperturbed rotational constants for the 2ν2 + ν6 state. Vibration-rotation interaction constants have been obtained for the ν2 and ν6 normal modes by combining the present results with those of previous workers. 相似文献
35.
Kang YS Lee HI Zhang Y Han YJ Yie JE Stucky GD Kim JM 《Chemical communications (Cambridge, England)》2004,(13):1524-1525
Highly ordered mesoporous materials constructed with integrated polymer-silica hybrid frameworks can be obtained via a one-step synthetic strategy using a mixture of polymer and silicate as the framework sources in the presence of a structure-directing agent. 相似文献
36.
To prove feasibility of proton chemical shift imaging ((1)H CSI) during stereotactic procedure, authors performed (1)H CSI in combination with a stereotactic headframe and selected targets according to local metabolic information, evaluated the pathologic results. The (1)H CSI directed stereotactic biopsy was performed in four patients. (1)H CSI and conventional Gd-enhancement stereotactic MRI were performed simultaneously after the fitting of a stereotactic headframe. Focal areas of increased phosphocholine(Cho)/phosphocreatine(Cr) and Lactate/Cr ratios were selected as target sites in the stereotactic MR images. (1)H CSI is possible with the stereotactic headframe in place. Pathologic samples taken from areas of increased Cho/Cr ratios and decreased NAA/Cr ratios provided information upon increased cellularity, mitoses and cellular atypism, and facilitated diagnosis. Pathologic samples taken from areas of increased Lac/Cr ratio showed predominant feature of necrosis. (1)H CSI was feasible with the stereotactic headframe in place. The final pathologic results obtained were concordant with the local metabolic information from (1)H CSI. We believe that (1)H CSI-directed stereotactic biopsy has the potential to significantly improve the accuracy of stereotactic biopsy targeting. 相似文献
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Kwang Ik KIM Zu Han LIU 《数学学报(英文版)》2008,24(1):75-86
We study the minimizers of the Ginzburg-Landau model for variable thickness, superconducting, thin films with high k, placed in an applied magnetic field hex, when hex is of the order of the "first critical field", i.e. of the order of |lnε|. We obtain the asymptotic estimates of minimal energy and describe the possible locations of the vortices. 相似文献
40.
Dong-Cheol Woo Chi-Bong Choi Sung-Ho Lee Eunjung Bang Sang-Soo Kim Hyang-Shuk Rhim Sang-Young Kim Bo-Young Choe 《Applied magnetic resonance》2010,38(1):65-74
The purpose of this study was to characterize the neurochemical profiles of various parts of the canine brain using proton
nuclear magnetic resonance spectroscopy, tissue extraction, and external simulated phantom concentration quantification. The
occipital, frontal, and temporal lobes, thalami, cerebellar cortices, and spinal cords of five pure bred adult beagles were
collected, and heavy water solutions for the nuclear magnetic resonance sample were prepared using the methanol–chloroform–water
extraction method. The metabolite concentrations in canine brain tissues were measured and compared with those found in human
and rat brain tissues. In addition, the cross peaks of Lac, Glu/Gln, and mIns were identified using two-dimensional correlation
spectroscopy in the canine frontal cortex. The present study demonstrated the absolute quantification of canine neuronal parts
using in vitro high-resolution magnetic resonance spectroscopy, with tissue extraction used to accurately measure metabolite
concentrations, thus providing valuable metabolic information regarding the various canine neuronal regions. 相似文献