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Nanogel nanosecond photonic crystal optical switching 总被引:3,自引:0,他引:3
Reese CE Mikhonin AV Kamenjicki M Tikhonov A Asher SA 《Journal of the American Chemical Society》2004,126(5):1493-1496
We developed a robust nanosecond photonic crystal switching material by using poly(N-isopropylacrylamide) (PNIPAM) nanogel colloidal particles that self-assemble into crystalline colloidal arrays (CCAs). The CCA was polymerized into a loose-knit hydrogel which permits the individual embedded nanogel PNIPAM particles to coherently and synchronously undergo their thermally induced volume phase transitions. A laser T-jump from 30 to 35 degrees C actuates the nanogel particle shrinkage; the resulting increased diffraction decreases light transmission within 900 ns. Additional transmission decreases occur with characteristic times of 19 and 130 ns. Individual NIPAM sphere volume switching occurs in the approximately 100 ns time regime. These nanogel nanosecond phenomena may be useful in the design of fast photonic crystal switches and optical limiting materials. Smaller nanogels will show even faster volume phase transitions. 相似文献
14.
C. Van den Abeele D. Ryckbosch G. De Meyer J. F. Dias L. Van Hoorebeke R. Van de Vyver J. -O. Adler K. Hansen L. Isaksson H. Ruijter P. Svensson B. Schröder 《Zeitschrift für Physik A Hadrons and Nuclei》1995,351(2):133-136
The values of the angle-integrated cross section for the decay to various low-lying states in39K following the40Ca(,) reaction at a mean photon energy of 60 MeV are reported on, together with the values of the reduced Legendre coefficientsa
i
. The40Ca(,gp) and40Ca(,n) reactions yield the same angular cross-section values and these agree with the corresponding RPA-calculations.Senior Research Associate NFWO 相似文献
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Strachan JD Adler H Alling P Ancher C Anderson H Anderson JL Ashcroft D Barnes CW Barnes G Batha S Bell MG Bell R Bitter M Blanchard W Bretz NL Budny R Bush CE Camp R Caorlin M Cauffman S Chang Z Cheng CZ Collins J Coward G Darrow DS DeLooper J Duong H Dudek L Durst R Efthimion PC Ernst D Fisher R Fonck RJ Fredrickson E Fromm N Fu GY Furth HP Gentile C Gorelenkov N Grek B Grisham LR Hammett G Hanson GR Hawryluk RJ Heidbrink W Herrmann HW Hill KW Hosea J Hsuan H Janos A Jassby DL Jobes FC 《Physical review letters》1994,72(22):3526-3529
17.
M. Adler A. Morozov T. Shiota P. van Moerbeke 《Communications in Mathematical Physics》1996,180(1):233-263
In this paper we solve the following problems: (i) find two differential operatorsP andQ satisfying [P, Q]=P, whereP flows according to the KP hierarchy P/t
n
=[(P
n/p
)+,P], withp:=ordP2; (ii) find a matrix a integral representation for the associated -function. First we construct an infinite dimensional spaceW= span{
0(z,
1(z,...)} of functions ofz invariant under the action of two operators, multiplication byz
p
andA
c
:=z/z–z+c. This requirement is satisfied, for arbitraryp, if
0 is a certain function generalizing the classical Hänkel function (forp=2); our representation of the generalized Hänkel function as adouble Laplace transform of a simple function, which was unknown even for thep=2 case, enables us to represent the -function associated with the KP time evolution of the spaceW as a double matrix Laplace transform in two different ways. One representation involves an integration over the space of matrices whose spectrum belongs to a wedge-shaped contour
-+
- defined by
± = +e±i/p. The new integrals above relate to matrix Laplace transforms, in contrast with matrix Fourier transforms, which generalize the Kontsevich integrals and solve the operator equation [P, Q]=1.The support of a National Science Foundation grant #DMS-95-4-51179 is gratefully acknowledged.The hospitality of the Volterra Center at Brandeis University is gratefully acknowledged.The hospitality of the University of Louvain and Brandeis University is gratefully acknowledged.The support of a National Science Foundation grant #DMS-95-4-51179, a Nato, an FNRS and a Francqui Foundation grant is gratefully acknowledged. 相似文献
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C. Bellmann A. Opfermann H.-J. Jacobasch H.-J. Adler 《Analytical and bioanalytical chemistry》1997,358(1-2):255-258
In the field of corrosion prevention, the characterisation of metal surfaces is useful to obtain information about the necessary
preparation of the surface and about the quality of thin coatings of coupling and protective agents. Electrokinetic measurements
can be used to determine the properties of modified polymer surfaces, metal sheets, and different surface preparations. However,
it was necessary first to create special conditions for measuring the streaming potential, such as electrical isolation of
the sample sheets together with the use of inert systems, as shown by the example of aluminium. According to the usual procedure
the metal was first coated with a thin layer of a coupling agent. The effect of this adhesive agent depends on the degree
of its adsorption by the metal surface. The quality of this layer can be characterised by streaming potential measurements,
which can show the degree of coverage, the adhesive strength of the coated layer, and the effective chemical properties of
the treated surface. These results were confirmed by wetting measurements. The production of surfaces which allow us to couple
a coating varnish to the adhesive agent in good quality was demonstrated.
Received: 24 June 1996 / Revised: 30 January 1997 / Accepted: 30 January 1997 相似文献