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Structure-toxicity relationships of nitroaromatic compounds 总被引:5,自引:0,他引:5
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S. Kabi A. Ghosh 《The European Physical Journal B - Condensed Matter and Complex Systems》2011,79(4):377-381
Electrical complex ac conductivity of the compound
Li0.9[Ni1/3Mn1/3Co1/3]O1.95 has been studied in the
frequency range 10 Hz–2 MHz and in the temperature range 93–373 K. It
has been observed that the frequency dependence of the ac conductivity obeys
a power law and the temperature dependence of the ac conductivity is quite
weak. The experimental data have been analyzed in the framework of several
theoretical models based on quantum mechanical tunneling and classical
hopping over barriers. It has been observed that the electron tunneling is
dominant in the temperature range from 93 K to 193 K. A crossover of
relaxation mechanism from electron tunneling to polaron tunneling is
observed at 193 K. Out of the several models discussed, the electron
tunneling and the polaron tunneling models are quite consistent with the
experimental data for the complex ac conductivity. The various parameters
obtained from the fits of the experimental results for the real and
imaginary parts of the conductivity to the predictions of these models are
quite reasonable. 相似文献
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L. T. Denisova L. A. Irtyugo V. V. Beletskii V. M. Denisov 《Physics of the Solid State》2016,58(7):1300-1303
Oxide compounds Pr2Sn2O7 and Nd2Sn2O7 have been obtained by solid-phase synthesis. The effect of temperature on the heat capacity of Pr2Sn2O7 (360–1045 K) and Nd2Sn2O7 (360–1030 K) has been studied using differential scanning calorimetry. The thermodynamic properties of the compounds (changes in enthalpy, entropy, and the reduced Gibbs energy) have been calculated by the experimental data of Cp = f(T). 相似文献
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《Journal of magnetic resonance. Series B》1995,106(2):131-141
The increasing use of perfluorocarbons (PFCs) as probes of tissue oxygenation on the basis of the 19F spin-lattice relaxation rate (R1) prompts comparison between several commercially available PFC blood-substitute emulsions, The relative sensitivities to both oxygen and temperature of the emulsions Oxypherol, Oxygent, and Fluosol at 7 T have been investigated, The linear response of R1 with pO2 was confirmed for each resonance in the range 4-50°C, In general, R1 is not a linear function of temperature, and we demonstrate this for perfluorotributylamine (FTBA) over an extended range of temperatures, 239-343 K. Theoretical R1 values of FTBA were compared with experimental data by computer modeling of relaxation mechanisms, To further understand the structure-function relationships of PFCs, 2D COSY experiments were used for the assignment of resonances and as an aid in interpretation of relaxation mechanisms, Finally, the utility of Oxygent and Oxypherol for measuring tissue pO2 in perfused rat hearts was compared before, during, and after eight minutes of global ischemia. 相似文献
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R. M. Eremina T. P. Gavrilova A. Günther Z. Wang R. Lortz M. Johnsson H. Berger H. A. Krug von Nidda J. Deisenhofer A. Loidl 《The European Physical Journal B - Condensed Matter and Complex Systems》2011,84(3):391-395
We report on magnetization and specific heat measurements on single-crystalline
CuTe2O5. The experimental data are directly compared to
theoretical results for two different spin structures, namely an alternating spin-chain
and a two-dimensional (2D) coupled dimer model, obtained by Das et al. [Phys. Rev. B
77, 224437 (2008)]. While the analysis of the specific heat does not allow
to distinguish between the two models, the magnetization data is in good agreement with
the 2D coupled dimer model. 相似文献
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Mikhail G. Brik Nicolae M. Avram Calin N. Avram 《Central European Journal of Physics》2005,3(4):508-524
The exchange charge model of crystal field theory has been used to analyze the ground and excited state absorption of tetrahedrally coordinated Cr4+ ion in lithium aluminum oxide LiAlO2 (γ-phase) and lithium dioxogallate LiGaO2. The parameters of the crystal field acting on the Cr4+ ion are calculated from the crystal structure data, taking into account the crystal lattice ions located at distances up to 12.744 Å in LiGaO2 and 13. 180 Å in LiAlO2. The obtained energy level schemes were compared with experimental ground and excited state absorption spectra and literature data on the application of other crystal field models (the angular overlap model and Racah theory) to the considered crystals; a good agreement with experimental data is demonstrated. 相似文献
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D. Varshney R. Sapkale G. J. Dagaonkar M. Varshney 《The European Physical Journal B - Condensed Matter and Complex Systems》2011,79(4):495-502
The mechanical, thermodynamical and elastic properties of Hg0.91Mn0.09Te compound are calculated by formulating an effective interionic interaction potential. This potential consists of the long-range
Coulomb, three body force parameter, the Hafemeister and Flygare type short-range overlap repulsion extended upto the second
neighbor ions and the van der Waals (vdW) interaction. The estimated values of phase transition pressure have revealed reasonably
good agreement with the available experimental data on the phase transition pressure P
t
= 11.5 GPa and the vast volume discontinuity in pressure-volume (PV) phase diagram indicate the structural phase transition
from zincblende (B3) to rock salt (B1) structure. Later on, the Poisson’s ratio ν, the ratio R
S/B
of S (Voigt averaged
shear modulus) over B (bulk modulus), elastic anisotropy parameter, elastic wave velocity, average wave velocity and Debye temperature as functions
of pressure is calculated. From Poisson’s ratio and the ratio R
S/B
it is inferred that Hg0.91Mn0.09Te is brittle in nature in both B3 phase
and B1 phase. To our knowledge this is the first quantitative theoretical prediction of the pressure dependence of ductile
(brittle) nature of Hg0.91Mn0.09Te compounds and still awaits experimental confirmations. 相似文献