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91.
92.
Andrej Ule 《Acta Analytica》2004,19(33):9-30
I analyze some classical solutions of the skeptical argument and some of their week points (especially the contextualist solution).
First I have proposed some possible improvement of the contextualist solution (the introduction of the explicit-implicit belief
and knowledge distinction beside the differences in the relevance of some counter-factual alternatives). However, this solution
does not block too fast jumps of the everyday context (where empirical knowledge is possible) into skeptical context (where
empirical knowledge is impossible). Then I analyze some formal analogies between some modal arguments on the contingency of
empirical facts (and the world as whole) and the skeptical arguments against empirical knowledge. I try to show that the skeptical
conclusion “Empirical knowledge does not exist” is logically coherent with the thesis that they are empirical facts and that
we have true belief on them. In order to do that without contradictions I have to accept a non-classical definition of knowledge:
S knows that p:= S is not justified to allow that non-p. Knowledge and justified allowance function here as some pseudo-theoretical
concepts which allow only some partial and conditional definitions by some “empirical” terms and logical conditions. 相似文献
93.
94.
We formulate coordinate-free conditions for identifying all the symmetry classes of the elasticity tensor and prove that these conditions are both necessary and sufficient. Also, we construct a natural coordinate system of this tensor without the a priory knowledge of the symmetry axes. 相似文献
95.
96.
Material symmetries of elasticity tensors 总被引:1,自引:0,他引:1
97.
98.
The electron transfer from aniline and its N-methyl as well as N-phenyl substituted derivatives (N-methylaniline, N,N-dimethylaniline, diphenylamine, triphenylamine) to parent solvent radical cations was studied by electron pulse radiolysis in n-butyl chloride solution. The ionization results in the case of aniline (ArNH2) and the secondary aromatic amines (Ar2NH, Ar(Me)NH) in the synchronous and direct formation of amine radical cations, as well as aminyl radicals, in comparable amounts. Subsequently, ArNH2*+ deprotonates in a delayed reaction with the present nucleophile Cl-, and forms further ArNH*. In contrast, tertiary aromatic amines such as triphenylamine and dimethylaniline yield primarily the corresponding amine radical cations Ar3N*+ or Ar(Me2)N*+, only. The persistent Ar3N*+ forms a charge transfer complex (dimer) with the parent amine molecule, whereas Ar(Me2)N*+ deprotonates to carbon-centered radicals Ar(Me)NCH2*. 相似文献
99.
Orinák A Arlinghaus HF Vering G Orináková R Hellweg S 《Journal of chromatography. A》2005,1084(1-2):113-118
New on-line analytical system coupling thin layer chromatography (TLC) and high selective identification unit-time of flight secondary ion mass spectrometry (TOF-SIMS) is introduced in this article. Chromatographic mixture separation and analyte surface deposition followed with surface TOF-SIMS analysis on-line allows to identify the analytes at trace and ultratrace levels. The selected analytes with different detectability and identification possibility were analysed in this hyphenated unit (Methyl Red indicator, Terpinolen and Giberrelic acid). Here, the chromatographic thin layer plays a universal role: separation unit, analyte depositing surface and TOF-SIMS interface, finally. Two depositing substrates and TOF-SIMS compatible interfaces were tested in above-mentioned interfacing unit: modified aluminium backed chromatographic thin layer and monolithic silica thin layer. The sets of positive and negative ions TOF-SIMS spectra obtained from different SIMS modes of analysis were used for analyte identification purposes. SIMS enables analyte detection with high mass resolution at the concentration level that is not achieved by other methods. 相似文献
100.
JPC – Journal of Planar Chromatography – Modern TLC - Thin layer chromatography with flame-ionization detection has been used for analysis of oligosaccharides. We report preliminary... 相似文献