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41.
Journal of Radioanalytical and Nuclear Chemistry - The influence of extraction process on Cs isotope ratios was investigated by thermal ionization mass spectrometry (TIMS) for nitric-acid (HNO3)...  相似文献   
42.
Target residues from the interaction of copper with 40MeV/nucleon 40Ar ions have been studied using thick-target, thick-catcher recoil techniques. Cross sections and average forward ranges were measured for 42 products. The data were used to obtain the mass yield distribution, the linear momentum transfer, and the excitation energy of composite systems. Comparison to similar studies for the interaction of copper with 12C ions at the same projectile energy per nucleon shows that the linear momentum transfer in central collisions depends strongly on the projectile mass.  相似文献   
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The interaction of ebselen, 2-phenyl-1,2-benzisoselenazol-3(2H)-one, a novel neuroprotective agent, with cyclodextrins (CyDs) in aqueous solution was studied by the solubility method and spectroscopic methods. The ability of sulfobutyl ether -CyD (SBE7--CyD, average degree of substitution= 6.2) to solubilize ebselen was greater, and its stability constant (> 2000 M-1) was significantly higher than those (< 1000 M-1) of other CyD complexes employed. The stability constant of the complexes rose as hydrophobicity of the substituents of CyDs increased, whereas it was negligibly affected by change in ionic strength of the medium, indicating a significant contribution of hydrophobic interaction in the complexation. SBE7--CyD gave positive and negative CD bands at around 320 and 350 nm, respectively, indicating that the guest is embedded in the asymmetric locus of the CyD cavity. 1H-NMR spectroscopic studies suggested that the mono-substituted benzene ring of ebselen is preferably included in the cavity of SBE7--CyD. The results indicate that SBE7--CyD is useful as a solubilizing agent for ebselen.  相似文献   
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Static characteristics of two different structured InAlGaAs/InAlAs superlattice avalanche photodiodes (SLAPDs) cooled by liquid nitrogen were evaluated at a wavelength of 1.5 μm. The dark current of the SLAPD having a thick superlattice layer of 0.504 μm was 5 × 10−13 A. This was successively reduced by four orders of magnitude compared to that of the thin layer SLAPD of 0.231 μm at a breakdown voltage of around 20 V. The thickened layer was effective in suppressing tunneling dark current. An output current of 1.7×l0−12 A at a bias voltage of 15 V was measured for an optical input with a wavelength of 1.5 μm and a signal power of 1 × 10−12 W. This showed a sharp distinction from the dark current.  相似文献   
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We construct a wonderful compactification of the variety parameterizing n distinct labeled points in X away from D, where X is a nonsingular variety and D is a nonsingular proper subvariety. When D is empty, it coincides with the Fulton–MacPherson configuration space.  相似文献   
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Synthesis of coformycin   总被引:2,自引:0,他引:2  
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