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71.
Bearman KR Blackmore DC Carter TJ Colin F Wright JD Ross SA 《Chemical communications (Cambridge, England)》2002,(9):980-981
Encapsulation of Amberlyst A-26 supported tribromide in a 10,000 MW polyethylene glycol matrix gives a robust colour-sensitive reagent matrix which can be deposited on indium-tin oxide coated polyvinylidene fluoride (PVDF) piezoelectric film for the detection of styrene (and other alkene) vapours. 相似文献
72.
We give a classification of 3—dimensional conformally flat contact metric manifolds satisfying: =0(=L
g) orR(Y, Z)=k[(Z)Y–(Y)Z]+[(Z)hY]–(Y)hZ] wherek and are functions. It is proved that they are flat (the non-Sasakian case) or of constant curvature 1 (the Sasakian case). 相似文献
73.
Synthesis of 8-dipropylamino-7,8,9,10-tetrahydrophenanthridines as potential serotoninergic agonists
A number of 8-dipropylamino-7,8,9,10-tetrahydrophenanthridines have been prepared as analogs of the known serotoninergic agonist 8-hydroxy-2-(dipropylamino)tetralin (8-OH-DPAT) and their affinity for the 5-HT1A receptor subtype evaluated by radioligand binding assay. 相似文献
74.
EMF versus Li-composition relation is determined by electrochemical insertion for Li-V5S8. The values of the thermodynamic functions ΔG, ΔH, ΔS corresponding to the lithium insertion reaction have been deduced. The Thompson method (electrochemical potential spectroscopy) has been applied to the V5S8 cathode, but it appears not valid in our case. The calculation of current versus time function is made to analyze the validity of this method. This technique requires: fast diffusion of Li in the host material, small grain size, small increments of applied voltage, low value of the cut-off current. 相似文献
75.
Changes in the magnetic field-temperature phase diagram of CeSb with pressure have been determined up to 6kbar by magnetization measurements on a single crystal. High magnetic fields up to 70 kOe have been applied along a four fold axis of the rock-salt type structure. The features of the phase diagram are not changed by pressure except for a shift towards high temperature. The saturated magnetic moment and the hysteresis of the transition fields are independent of pressure. Variation of exchange energy with volume is deduced from the experimental results. It is shown that the effect of pressure and the magnetic volume anomaly at 0 K are essentially due to the variation of the exchange energy in the ferromagnetic (001) planes. 相似文献
76.
We compute the 2-rank of the wild kernel WK2(F) of a number field by constructing a 2-class group ad hoc. The main result generalizes in the more intricate case the canonical isomorphism established for odd primes under the assumption in a previous article (cf. (Acta. Arith. 67 (1994) 335; Math. Z. 238 (2001) 335)). It involves a criterium of triviality for the 2-part of the wild kernel of Galois number fields and, in the particular case of quadratic fields, it leads to a logarithmic interpretation of the diophantine conditions obtained by other authors. 相似文献
77.
In the present paper we classify the conformally flat contact metric
manifolds of dimension
satisfying
.
We prove that these manifolds are Sasakian of constant curvature 1. 相似文献
78.
A method is proposed to find the digital input signals to enter in nonlinear acoustical systems (power amplifiers, transducers, etc.) in order to obtain desired arbitrary response signals. The searched input signals are found by performing a Monte Carlo search guided by a simulated annealing process applied to a hidden model with a small number of parameters. The physical system is actually used in the optimization procedure, in a real-time manner, so that no theoretical model of the system response is required. The main aspects of the algorithm are described and illustrated with several examples. 相似文献
79.
Nanoscopic scale studies of LiFePO4 as cathode material in lithium-ion batteries for HEV application
We present a review of the structural properties of LiFePO4. Depending on the mode of preparation, different impurities can poison this material. These impurities are identified and
a quantitative estimate of their concentrations is deduced from the combination of X-ray diffraction analysis, Fourier transform
infrared spectroscopy, Raman spectroscopy, and magnetic measurements. An optimized preparation provides samples with carbon-coated
particles free of any impurity phase, insuring structural stability and electrochemical performance that justify the use of
this material as a cathode element a new generation of lithium secondary batteries. 相似文献
80.