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51.
We developed photochemically controlled photonic crystals which may be useful in novel recordable and erasable memories and/or
display devices. These materials can operate in the UV, visible or near IR spectral regions. Information is recorded and erased
by exciting the photonic crystal with ∼ 360 nm UV light or ∼ 480 nm visible light. The recorded information is read out by
measuring the photonic crystal diffraction wavelength. The active element of the device is an azobenzene functionalized hydrogel
which contains an embedded crystalline colloidal array. UV excitation forms cis-azobenzene while visible excitation forms
trans-azobenzene. Larger dipole moment of the cis-form results in decrease of the free energy of mixing which causes the hydrogel
to swell and to red-shift the photonic crystal diffraction with a 36 s time constant. We also observed fast ms and sub-ms
transient dynamics associated with convection due to heating of the medium by UV excitation. Convective motion of the medium
stretches the PCCA for about 6 μs within which the convection decays and the elastic restoring force of the PCCA brings back
the stretched PCCA to its equilibrium state with 33 μs time constant.
Paper presented at the 2nd International Conference on Ionic Devices, Anna University, Chennai, India, Nov. 28–30, 2003. 相似文献
52.
JPC – Journal of Planar Chromatography – Modern TLC - Emodin and twelve phenolic acids (ellagic, gallic, protocatechuic, homoprotocatechuic, caffeic, p-hydroxybenzoic, p-coumaric,... 相似文献
53.
54.
Joanna Tarasińska 《Applications of Mathematics》2003,48(1):67-72
Two estimates of the regression coefficient in bivariate normal distribution are considered: the usual one based on a sample and a new one making use of additional observations of one of the variables. They are compared with respect to variance. The same is done for two regression lines. The conclusion is that the additional observations are worth using only when the sample is very small. 相似文献
55.
56.
Grzegorz M. Salamończyk 《Tetrahedron letters》2003,44(40):7449-7453
An efficient synthesis of antiviral dendritic prodrug candidates, water-soluble, polyanionic conjugates of 1st and 2nd generation thiophosphate dendrimers with acyclovir, is described. 相似文献
57.
The Schlesinger equations S
(n,m) describe monodromy preserving deformations of order m Fuchsian systems with n + 1 poles. They can be considered as a family of commuting time-dependent Hamiltonian systems on the direct product of n copies of m × m matrix algebras equipped with the standard linear Poisson bracket. In this paper we present a new canonical Hamiltonian formulation
of the general Schlesinger equations S
(n,m) for all n, m and we compute the action of the symmetries of the Schlesinger equations in these coordinates. 相似文献
58.
Hubert Grudzński 《Reports on Mathematical Physics》2004,53(3):331-338
New elements of the dual cone of the set of fermion N-representable 2-density operators are proposed. So far, the explicit form of the corresponding necessary conditions for N-representability is obtained for N = 3. In this case the new condition is stronger than the known B- and C-conditions for 3-representability. The results provide evidence that in the spectral decomposition of the N-representable 2-density operator there exists an intrinsic relation between the eigenvalue and the corresponding eigenfunction. 相似文献
59.
Orewczyk J. Jasieńska S. Iwanczenko S. 《Journal of Thermal Analysis and Calorimetry》1998,54(1):79-84
This paper presents applications of thermal analysis to observe the course of reduction of acidic pellets, metallurgical substances
whose reducibility and strength are basic parameters of use in blast furnace processes. Both parameters depend on the mineral
composition of the samples. The investigations included determination of the chemical and phase compositions of the initial
samples and reduction products.
Research was conducted on acidic pellets from Połtawa (Poland), applied in the T. Sendzimir Steelworks (Poland), in comparison
with pellets from Brazil, Canada and Lebedyn (Russia).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
60.