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1.
An electrical resistivity minimum has been found at low temperature in high-concentrated AuCr alloys with an antiferromagnetic long-range order. The anomalous part obtained under a simple assumption is approximately proportional to ? log T, and increases with Cr concentration up to the solubility limit.  相似文献   
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L-Threonine was transformed, stereospecifically, to a versatile β-lactam (5a) in 3 steps. This β-lactam was further converted to a key intermediate (25) for the synthesis of thienamycin and its biologically active analogues. Furthermore, the compound 5a was changed to iodides (18 and 23), cyanides (19 and 24), chloromethylketone (26) and aldehydes (30 and 31) which appear to have a latent potential as precursors for the syntheses of the carbapenems.  相似文献   
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Lipid A analogues containing glucose in substitution for glucosamine on the reducing end were synthesized, and the inhibitory activities on LPS-induced TNFα production (LPS-antagonistic activity) in vitro using human whole blood cells were measured. The IC50 values (nM) of these ten compounds, 8, 14, 21, 31, 40, 51, 57, 62, 67 and 72, were 11.2, 15.4, 2.7, 0.1, 0.4, 1.3, 3.2, 3.2, 1.4 and 14.4, respectively. And also inhibitory activities (ID50) on TNFα production toward galactosamine loaded C3H/HeN mice in vivo of compounds 21, 31, 57, 62 and 67 were measured. The values of these compounds were 0.29, 0.50, 0.61, not dose-dependent and 0.33 mg/kg, respectively.  相似文献   
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Phenomenological treatments of ferrielectrics are made in terms of two non-equivalent sublattice polarizations in the paraelectric phase. Unlike the Curie-Weiss behaviour of usual proper ferro- and antiferro-electrics, the dielectric susceptibility does not depend linearly on temperature. Particularly in the case of a first order phase transition, the Curie-Weiss constant seems to be unusually small. As an example, the dielectric properties of (NH4)2SO4, which was known to be a peculiar ferroelectric, is discussed from the ferrielectric point of view. The true Curie-Weiss constant is of a comparable order of magnitude to that of the order-disorder ferroelectric.  相似文献   
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Base treatment of N-propargyl epoxyamide 5 afforded the acetylenic 3-(hydroxyethyl)-2-azetidinone 9a, which was subsequently transformed to phenyl thiolester 2, a versatile intermediate for the carbapenem synthesis.  相似文献   
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Electronic Raman scattering has no sum rule in no and weak correlation, but the existence of sum rule has been proposed in strong correlation. The present Raman scattering disclosed that the first moment of the Raman susceptibility is proportional to the generalized moment of the optical conductivity in the metallic phase. The present experiment disclosed that a large amount of electronic states are incoherent states. The incoherent states are the relevant states for the superconductivity, because the gap opens in the incoherent states as well as the coherent states.  相似文献   
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Lipid A analogues containing a glucose moiety on their non-reducing end were synthesized, and their LPS-antagonistic activities were measured. The inhibitory activities (IC50) on LPS-induced TNFα production of these six compounds, 26, 33, 44β, 52β, 59, and 61, toward human whole blood cells were 0.49, 0.65, 0.51, 0.98, 0.46, and 1.11 nM, respectively. Inhibitory doses (ID50) of compounds 26, 33, 44β, 59, and 61 on TNFα production induced by coinjection of galactosamine and LPS in C3H/HeN mice were measured. The ID50 values of these compounds were 0.45, 0.96, <0.2, 1.08, and <0.2 mg/kg, respectively. Moreover, C3H/HeN mice preinjected with compounds 26, 33, and 44β were protected from lethality induced by coinjection of galactosamine and LPS. Out of eight mice preinjected with 1 mg/kg of compounds 26, 33, and 44β, five, eight and six mice were protected, respectively.  相似文献   
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