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1.
The yellow complex of Pt(IV) with 1-pyridyl-4,4,6-trimethyl-1H,4H-pyrimidine-2-thiol (PyTPT) which has maximum absorbance at 430 nm, is studied for the spectrophotometric determination of the metal. Molar absorptivity is 5000 liters mol?1 cm?1 and Sandell's sensitivity is 0.039 μg/cm2. The determination of Pt(IV) (2.8–8.4 ppm) in the presence of diverse ions is described. 相似文献
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5.
Upon adsorption of various vapours, the electrical conductivity of lycopene semiconductor changes appreciably This phenomenon had been used as a probe to study the adsorption and desorption processes in these polyene crystals The adsorption and desorption kinetics have been found to follow a modified Roginsky-Zeldovich relation A three-stage adsorption process has been identified The first stage gives a Lennard-Jones potential energy curve, followed by a transition over a potential barrier to the second stage of adsorption in a potential well In the third stage a deep potential energy surface is reached by activation over a second potential barrier and strongly bound complexes between the vapour molecules and the surface molecules of the crystals are finally formed. 相似文献
6.
N. Pathak G. K. Mahanti T. K. Sinha Mahapatra 《International Journal of Infrared and Millimeter Waves》2007,28(11):953-960
In this paper, we present a new method based on real-coded Genetic Algorithm (GA) with elitist model for optimal design of
a reconfigurable symmetrical dual-beam uniformly spaced linear isotropic antenna array with phase-only control of quantized
phase shifters. The problem is to find a common amplitude distribution that will generate a pencil beam with zero phases and
a flat-top beam with discrete phases of a six-bit discrete phase shifter, without or with pre-fixing the value of dynamic
range ratio (|I
max/I
min|) of excitation current amplitude distribution equal to or less than five. 相似文献
7.
We use different determinantal Hartree-Fock (HF) wave functions to calculate true variational upper bounds for the ground
state energy of N spin-half fermions in volume V
0, with mass m, electric charge zero, and magnetic moment μ, interacting through magnetic dipole-dipole interaction. We find that at high
densities when the average interparticle distance r
0 becomes small compared to the magnetic length r
m ≡ 2mμ2/ħ2, a ferromagnetic state with spheroidal occupation function n
↑(), involving quadrupolar deformation, gives a lower upper bound compared to the variational energy for the uniform paramagnetic
state or for the state with dipolar deformation. This system is unstable towards infinite density collapse, but we show explicitly
that a suitable short-range repulsive (hard core) interaction of strength U
0 and range a can stop this collapse. The existence of a stable equilibrium high density ferromagnetic state with spheroidal occupation
function is possible as long as the ratio of coupling constants Γcm ≡ (U
0
a
3/μ2) is not very small compared to 1.
相似文献
8.
Gabriella Kervefors Kumar Bhaskar Pal Gergely L. Tolnai Mukul Mahanti Hakon Leffler Ulf J. Nilsson Berit Olofsson 《Helvetica chimica acta》2021,104(2):e2000220
β-Galactose derivatives have recently been reported to selectively inhibit galectin-3, and a library of O3-arylated galactosides with varying substitution patterns was designed to study such inhibitions further. The O3-arylated galactosides were synthesized using diaryliodonium salts under mild and transition metal free conditions, providing the target products in moderate to good yields. An O3-trifluoroethylated galactoside was also synthesized using iodonium salt chemistry. Azido-substituted products were subsequently transformed into the corresponding triazoles. After deprotection, a selection of galactoside derivatives were evaluated for inhibitory potencies against galectins-1, 3, 4 N (N-terminal domain), 4 C (C-terminal domain), 7, 8 N, 8 C, 9 N, and 9 C and one compound with promising affinity and selectivity for both the N- and C-terminal domain of galectin-9 was discovered. 相似文献
9.
The kinetics of substitution of aqua ligands fromcis-[Ru(bipy)2(H2O)2]2+ ion by salicylhydroxamic acid (L) in aqueous medium has been studied spectrophotometrically at different temperatures (50–65°C).
The following rate law has been established in the pH range 4.0 to 5.8;
相似文献
10.
In Bani?, ?repnjak, Merhar and Milutinovi? (2010) [2] the authors proved that if a sequence of graphs of surjective upper semi-continuous set-valued functions fn:X→X2 converges to the graph of a continuous single-valued function f:X→X, then the sequence of corresponding inverse limits obtained from fn converges to the inverse limit obtained from f. In this paper a more general result is presented in which surjectivity of fn is not required. The result is also generalized to the case of inverse sequences with non-constant sequences of bonding maps. Finally, these new theorems are applied to inverse limits with tent maps. Among other applications, it is shown that the inverse limits appearing in the Ingram conjecture (with a point added) form an arc. 相似文献
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