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1.
Shijie Liu Georg Roeder Gulnur Aygun Kristian Motzek Peter Evanschitzky Andreas Erdmann 《Optik》2012,123(10):928-931
A 3D model is set up to simulate the exposure process of inclined/rotated UV lithography for negative SU-8 resists. The formation of inclined resist pillars and microstructures with truncated cone shapes is simulated based on a 3D exposure model in combination with a post exposure bake model for chemically amplified resists and the Mack development model. As one of the interesting applications employing this promising lithography technique for MEMS fabrication, a solid microneedle for drug delivery is simulated. 相似文献
2.
The magnetic phase diagram of amorphous Ni80? x Fe x B16Si4 was studied by de-magnetization measurement, by57Fe-Mössbauer spectroscopy and pulsed spin echo NMR. 相似文献
3.
Adams MR Aïd S Anthony PL Averill DA Baker MD Baller BR Banerjee A Bhatti AA Bratzler U Braun HM Breidung H Busza W Carroll TJ Clark HL Conrad JM Davisson R Derado I Dhawan SK Dietrich FS Dougherty W Dreyer T Eckardt V Ecker U Erdmann M Faller F Fang GY Figiel J Finlay RW Gebauer HJ Geesaman DF Griffioen KA Guo RS Haas J Halliwell C Hantke D Hicks KH Hughes VW Jackson HE Jancso G Jansen DM Jin Z Kaufman S Kennedy RD Kinney ER Kirk T Kobrak HG Kotwal AV Kunori S Lancaster S Lord JJ Lubatti HJ 《Physical review letters》1995,74(9):1525-1529
4.
Synchronization between experimental observations and a dynamical model with undetermined parameters can assist in completing the specification of the model parameters. The quality of the synchronization, a cost function to be minimized, typically depends on the difference between the data time series and the model time series. If the coupling between the data and the model is too strong, this cost function is small for any data and any model, and the variation of the cost function with respect to the parameters of interest is too small to permit selection of a value of the parameters. If the coupling is too small, synchronization is lost. We introduce two methods for balancing the competing desires of a small cost function and the numerical ability to determine parameters accurately. One method of ‘balanced’ synchronization adds a requirement that the conditional Lyapunov exponent of the model system, conditioned on being driven by the data, remain negative but small. The other method allows the coupling to vary in time according to the error in synchronization. This second method succeeds because the data and the model exhibit generalized synchronization in the region where the parameters of the model are well determined. 相似文献
5.
Jeanne Bamberger Andrea diSessa 《International Journal of Computers for Mathematical Learning》2003,8(2):123-160
The argument examined in this paper is that music – when approached through making and responding to coherent musical structures,facilitated
by multiple, intuitively accessible representations – can become a learning context in which basic mathematical ideas can
be elicited and perceived as relevant and important. Students' inquiry into the bases for their perceptions of musical coherence
provides a path into the mathematics of ratio,proportion, fractions, and common multiples. Ina similar manner, we conjecture
that other topics in mathematics – patterns of change,transformations and invariants – might also expose, illuminate and account
for more general organizing structures in music. Drawing on experience with 11–12 year old students working in a software
music/math environment, we illustrate the role of multiple representations, multi-media, and the use of multiple sensory modalities
in eliciting and developing students' initially implicit knowledge of music and its inherent mathematics.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
6.
M.?Erdmann S.?Baumann S.?Gr?fe V.?EngelEmail author 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2004,30(3):327-333
The combined electronic and nuclear motion during a predissociation process is studied in a model system. The latter consists of an electron and an ion which are allowed to move in one dimension and interact with each other and two fixed ions via screened Coulomb interactions. The fragmentation dynamics is illustrated in terms of the temporal changes of electronic and nuclear densities. In this way it is possible to reveal the influence of non-adiabatic coupling, not only on the nuclear wave-packet motion, but also on the transient electronic structure.Received: 10 June 2004, Published online: 24 August 2004PACS:
31.50.Gh Surface crossings, non-adiabatic couplings - 31.70.Hq Time-dependent phenomena: excitation and relaxation processes, and reaction rates 相似文献
7.
8.
Many nitrogen- and sulfur-containing heterocyclic compounds exhibit biological activity. Among these heterocycles are benzo[4,5]thiazolo[2,3-c][1,2,4]triazoles for which two main synthetic approaches exist. Here we report a new synthetic protocol that allows the preparation of these tricyclic compounds via the oxidation of a mercaptophenyl moiety to its corresponding disulfide. Subsequent C-H bond functionalization is thought to enable an intramolecular ring closure, thus forming the desired benzo[4,5]thiazolo[2,3-c][1,2,4]triazole. This method combines a high functional group tolerance with short reaction times and good to excellent yields. 相似文献
9.
Excitons of polydiacetylene chains, diluted in a 3BCMU monomer single crystal, turn at very low light intensity into a nonabsorbing polariton state once the polymer concentration exceeds 10{-4} in weight. The transition is evident from a Lorentzian absorption peak which is truncated at an optical density OD approximately 2 and is consistent with polariton coupling of light to eigenstates of the solid while Rabi coupling of individual chains to light is excluded. The saturated absorption is nearly independent of polymer content and crystal thickness and defines a surface region where photons are converted into polaritons, the corresponding electromagnetic eigenmodes of matter. 相似文献