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1.
Nanocrystals of the semiconducting chalcopyrite CuFeS2 have been synthesized utilizing a facile solution-based method. Depending on the choice of precursors and synthesis conditions, the nanocrystals exhibit either a spherical (~12 nm) or pyramidal morphology (~30 nm), with a narrow size distribution. The band gap of the pyramidal nanocrystals is very close to the bulk value, but a larger band gap is obtained for the spherical nanocrystals likely because of size confinement effect. 相似文献
2.
Hemoglobin was isolated from chicken blood and purified by biochemical methods.This hemoglobin was allowed to interact with copperglutathione (CuGSH) and the interaction pattern was monitored by spectrophotometric and spectrofluorimetric techniques. The interaction ratio was found to be 1:0.7 in both the cases. The equilibrium constant data suggested associative binding and a fluorimetric study revealed that such association occurred around tryptophan residues of hemoglobin. 相似文献
3.
Mathematische Annalen - 相似文献
4.
This article initiates a detailed analysis of the spectral representation for the ground state representation of the infinite one-dimensional Heisenberg ferromagnet. Here, we obtain explicit expressions for the infinite volume (weak) limits of the projections constructed from Bethe's eigenfunctions for the finite volume Heisenberg Hamiltonians. Assuming the limits are projections, we establish various spectral properties for the Hamiltonian restricted to the corresponding subspaces. 相似文献
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8.
Ramasamy K Mazumdar D Zhou Z Wang YH Gupta A 《Journal of the American Chemical Society》2011,133(51):20716-20719
Nanocrystals and nanoclusters of the room-temperature magnetic spinel CuCr(2)S(4) have been synthesized using a facile solution-based method. The synthesis involves hot injection of an excess of 1-dodecanethiol (1-DDT) into a boiling coordinating solvent containing CuCl(2) and CrCl(3)·6H(2)O. Using octadecylamine (ODA) as a solvent yields cube-shaped nanocrystals with an average size of 20 ± 2 nm, while with oleylamine (OLA), nanoclusters with an average size of 31 ± 2.5 nm are obtained. In both cases, powder X-ray diffraction patterns confirmed the formation of the pure spinel phase without any impurities. While the synthesized powders are superparamagnetic near room temperature, they exhibit ferromagnetic behavior at lower temperatures, with magnetization (M(S)) values of 30 emu/g (1.63 μ(B)/f.u.) and 33 emu/g (1.79 μ(B)/f.u.) for the ODA- and OLA-capped nanocrystals and nanoclusters, respectively, at 5 K. 相似文献
9.
Consider a sequenceF
1,F
2,... of i.i.d. random transformations from a countable setV toV. Such a sequence describes a discrete-time stochastic flow onV, in which the position at timen of a particle that started at sitex isM
n(x), whereM
n
=F
n
F
n–1
F
1. We give conditions on the law ofF
1 for the sequence (M
n) to be tight, and describe the possible limiting law. an example called the block charge model is introduced. The results can be formulated as a statement about the convergence in distribution of products of infinite-dimensional random stochastic matrices. In practical terms, they describe the possible equilibria for random motions of systems of particles on a countable set, without births or deaths, where each site may be occupied by any number of particles, and all particles at a particular site move together. 相似文献
10.
Summary In this paper, we continue earlier works of one of the authors on vague convergence of the sequence
k,n=
k+1 *...*
n, where
n is a sequence of probability measures on semigroups or groups. Typical results in this paper are: Theorem. Let S be a locally compact noncompact second countable group such that
being the support of a probability measure on S. Suppose there exists an open set V with compact closure such that x
–1
Vx=V for every xS. Then for all compact sets K, sup{
n
(Kx): xS0 as n. Theorem. Let S be an at most countable discrete group. Let
n be a sequence of probability measures on S. Then for all nonnegative integers k, the sequence
k,n converges vaguely to some probability measure if and only if there exists a finite subgroup G such that the series
and for any proper subgroup G of G and any choice of elements gn in S, the series
. A sufficient condition for the vague convergence of the sequence
k,n to a probability measure is that (i) there exists a finite subgroup G such that
and (ii)
n(e)>s>0 for all n, e being the identity.The author was supported by NSF grant MCS77-03639 相似文献