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151.
Does there exist any equivalence between the notions of inconsistency and consequence in paraconsistent logics as is present in the classical two valued logic? This is the key issue of this paper. Starting with a language where negation (?{neg}) is the only connective, two sets of axioms for consequence and inconsistency of paraconsistent logics are presented. During this study two points have come out. The first one is that the notion of inconsistency of paraconsistent logics turns out to be a formula-dependent notion and the second one is that the characterization (i.e. equivalence) appears to be pertinent to a class of paraconsistent logics which have double negation property.  相似文献   
152.
The line shape parameters of rovibrational transitions of water vapour belonging to the (2ν1 + ν2 + ν3) overtone band due to collisions between absorber molecules and noble gas helium have been measured in the spectral range between 11988.494 cm?1 and 12218.829 cm?1 using NIR diode laser spectrometer. In addition nitrogen and air broadening effects on some water vapour transitions belonging to the same band have also been studied. Wavelength modulation spectroscopy along with phase sensitive detection technique are used to record first derivative (1f) signal of buffer gas broadened water vapour transitions. Observed line shapes are fitted to standard Voigt profiles by non-linear least squares fitting program to extract the line shape parameters, like line strength and pressure broadening coefficients. The broadening effects induced by different types of buffer gases on water vapour line shapes are compared. Rotational quantum number (J) dependence of broadening coefficients of water vapour transitions is also examined.  相似文献   
153.
154.
We simulate viscous fingering generated by separating two plates with a constant force, in a lifting Hele-Shaw cell. Variation in the patterns for different fluid viscosity and lifting force is studied. Viscous fingering is strongly affected by anisotropy. We report a computer simulation study of fingering patterns, where circular or square grooves are etched on to the lower plate. Results are compared with experiments.  相似文献   
155.
Liquid chromatography/mass spectrometry (LC/MS) has been applied to analyze N,N'-ethylenebisdithiocarbamate fungicides (EBDCs: manzeb, maneb and zineb) in environmental water samples. The EBDCs that are zinc and/or manganese salts are transformed into readily water-soluble sodium salts by adding an alkaline EDTA solution. The N,N'-ethylenebisdithiocarbamate anion is extracted into chloroform-hexane (3:1) as an ion pair with tetrabutylammonium, and then S-alkylated with methyl iodide. The extraction and derivatization are carried out at room temperature. The derivatized ethylenebisdithiocarbamic acid dimethyl ester is introduced into an LC/MS equipped with a negative ion electrospray ionization interface. Identification of the compound is performed with the specific quasi-molecular ion, and the quantitative analyses are carried out using the peak areas. The average recoveries and coefficients of variation of EBDCs at sub-ppb level are 79.1% and 29.3% (n = 6), respectively. The limit of detection based on standard deviation of 0.043 microg/L for manzeb is achieved.  相似文献   
156.

We will show that any infinite sequence of epimorphisms between finitely generated hyperbolic 3-manifold groups eventually consists of isomorphisms.

  相似文献   

157.
158.
The temperature dependence of the thermal expansion for GaAs and InP is investigated theoretically using the experimental pressure derivatives of elastic stiffness constants and phonon frequencies. The linear correlation between the transverse acoustical mode Grüneisen parameter γXTA and the metallic transion pressure Pt obtained by Weinstein is not satisfied for GaAs and InP, but the observed thermal expansion of GaAs is well reproduced. In addition, the linear expansion coefficient of InP is predicted theoretically as a function of temperature. Then, the phonon dispersion curves of GaAs and InP at their covalent-metallic transition pressures are quantitatively shown.  相似文献   
159.
The surface of montmorillonite, a hydrophilic layer silicate, was modified with alkylammonium and alkylpyridinium cations with the aim of producing Pd nanoparticles within the hydrophobized interlamellar space. The structure and interlamellar swelling of hexadecylpyridinium and tetradodecylammonium montmorillonite were first studied in tetrahydrofuran-ethanol mixtures. It was established that both hydrophobic montmorillonites swell readily in tetrahydrofuran and the interlamellar spaces may be employed as nanoreactors for the synthesis of Pdo particles. Ethanol was adsorbed on the surface of the hydrophobic support. After addition of the precursor Pd-acetate, metallic Pd was produced on the external and internal surfaces of the support. The diameter of the particles formed was in the range of 2-5 nm as shown by TEM.  相似文献   
160.
A highly convergent total synthesis of bitungolide F leading to the assignment of its absolute stereochemistry is described. The key steps include a Horner-Wadsworth-Emmons olefination to construct the C7-C8 bond, a Wittig reaction to introduce the conjugate E,E-olefinic moiety in the molecule, and finally a ring-closing metathesis reaction to construct the six-membered alpha,beta-unsaturated delta-lactone of the molecule. Modified Evans's syn-aldol reaction, using Crimmins's protocol, was used to install the stereochemistries at the C4 and C5 centers. The stereochemistry at C9 was introduced by means of hydroxy-directed reduction of the C9 keto using Evans's protocol.  相似文献   
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