Induced pattern

No swelling-induced pattern deformation occurs and high aspect ratio sub-half-micron patterns in 1 micron film thickness are obtained with high sensitivity. 

We have found the combination of the azide compound and the styrene resin is well suited for achieving high resolution and high aspect ratio patterns using KrF excimer laser stepper system, because of the absence of swelling-induced pattern deformation during alkaline development and the suitable optical density at 248 nm in terms of sensitivity. 

The Decontaksolv system uses extraction fluids to desorb and solubilize the PCB components from wall surfaces and the core and windings of equipment. The efficiency of decontamination is a function of the induced pattern of phase change of the extraction fluid within the material containing the PCBs, a different pattern being used for each type of equipment. The decontamination mode used depends on the type of equipment, transformers, capacitors, or other material being processed, and on the size of the equipment and concentration of PCBs. 

Patterns Generated by the Outer Membrane. As in the single cell case, the outer membrane itself can generate electro-physiological patterns, even in the absence of reactions in the cell mass, R = 0. Such surface induced patterns were first discussed in the context of reaction-diffusion patterns in Ref. 

V.Z. Yakhnin, A.B. Rovinsky, and M. Menzinger, Differential-flow-induced pattern formation in the exothermic A B reaction, J. Phys. Chem. 95 2116 (1994). 

Sallaz M, Jourdan F. 1992. Apomorphine disrupts odour-induced patterns of glomerular activation in the olfactory bulb. Neuroreport 3 833-836. 

However, the reader should be aware that there are many other systems in which different types of patterns have been observed that result from a qualitatively different kind of coupling. Hence they also require fundamentally different models from that considered in this chapter. This first includes convection-induced patterns. These might arise from large concentration gradients in the solutions or different sinface tensions as found, for example, under certain conditions for anodic metal dissolu-or for some inhibited charge-transfer processes at Hg elec-... 

To characterize the coherence of noise-induced patterns in the distributed excitable medium we calculate the relative fluctuations of the spatial average C/i(t) of the activator field u x,t)... 

In order to control the noised-induced patterns, we will now use the method of time-delayed feedback which was previously applied successfully in deterministic chaos control of this particular system [47] as well as for control of noise-induced oscillations in simple models [7-9] without spatial degrees of freedom. 

A. G. Balanov, V. Beato, N. B. Janson, H. Engel, and E. Scholl Delayed feedback control of noise-induced patterns in excitable media, Phys. Rev. E... 

N. E. Voicu, S. Harkema, and U. Steiner, Electric-field-induced pattern morphologies in thin liquid films. Adv. Funct. Mat. 16, 926 (2006). 

Abstract A systematic overview of various electric-field induced pattern forming instabilities in nematic liquid crystals is given. Particular emphasis is laid on the characterization of the threshold voltage and the critical wavenumber of the resulting patterns. The standard hydrodynamic description of nematics predicts the occurrence of striped patterns (rolls) in five different wavenumber ranges, which depend on the anisotropies of the dielectric permittivity and of the electrical conductivity as well as on the initial director orientation (planar or homeotropic). Experiments have revealed two additional pattern types which are not captured by the standard model of electroconvection and which still need a theoretical explanation. 

Case G planar alignment, 6 < 0 o-q < 0. Standard EC (based on the CH mechanism) cannot occur for the material parameter combination e < 0, da < 0 [2] except the a induced" pattern type. Nevertheless, convection associated with roll formation has been observed in ac electric field in the homologous series of N-(p-n-alkoxybenzylidene)-n-alkylanilines, di-n-4-4 -alkyloxyazoxybenzenes and 4-n-alkyloxy-phenyl-4-n alkyloxy-benzoates [52-54]. The characteristics of the patterns the orientation of the rolls, contrast, frequency dependence of the wavevector and the threshold, director variation in space and time etc. - are substantially different from those observed in the standard EC. Since this roll formation process falls outside of the frame of the standard model, it has been called nonstandard electroconvection (ns-EC). 

Fig. 9.1 (a) Evolution of swelling-induced pattern formation on acrylamide hydrogel formed in a petri dish, (b) The schematic of the gel before and after swelling (left), and the condition for instability plotted for two independent parameters (right). (Reprinted by permission from Macmillan Publishers Ltd Nature [19], 1987)... 

Self-oscillatory patterns can be created by repeating swelling and de-swelling of the polymer network in a closed system, i.e., without any external stimuU. In comparison to stimuli-induced patterns (summarized above), self-oscillatory patterns have no on-off switch, and can repeat itself periodically, such as a beating heart (Fig. 9.9). The idea was based on Belousov-Zhabotinsky (BZ) type reaction [66] to induce spontaneous temporal change in the redox potential to control swelling... 

Xiang, H Lin, Y Russell, T.P. Electrically induced patterning in block copolymer films. Macromolecules 37, 5358-5363 (2004)... 

N. Eber, L.O. Palomares, P. Salamon, A. Krekhov and A. Buka, Temporal evolution and morphological transitions of electric field induced patterns at low frequency driving, (unpublished). 

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