Reversible tunability

Switching of an H-PDLC has also been accomplished mechanically [29], By using a relatively elastic photopolymer, De Rosa and coworkers were able to switch off the gratings by applying a shear stress to the cell. LC alignment may play a role in the results, however, the authors attributed the effect to a tilting of the grating. In other words, the direction of diffraction should be reversibly tunable by this method. 

A interesting recent precedent related to the reversibly tunable exfoliation of SWNTs using poly(acrylic acid) at varying pH levels is reported by Grunlan, J. C. Liu, L. Kim, Y. S. Nano Lett. 2006, 6,911. 

Usually, the size separation porous membranes have cutoff values for their smallest diameter on their transmembrane path, and the cutoff diameter is not usually tunable once they are synthesized. Utilizing supercompressible and fully elastic properties, CNMs were designed with mechanically reversible tunable pores. The CNM (-300 pm thick) with an... 

M. Mathews, N. Tamaoki, Reversibly tunable helicity induction and inversion in liquid crystal self-assembly by a planar chiropdc trigger molecule. Chem. Commun. 3609-3611 (2009)... 

Reversible tunability of reflective coloration using diarylethene-containing GLCs is envisioned in Figure 12. 

Minko S., Muller M., Motornov M., Nitschke M., Grundke K., and Stamm M., Two-level structured self-adaptive surfaces with reversibly tunable properties , J Am Chem Soc, 2003 125(13) 3896-3900. 

There is considerable interest in developing new types of magnetic materials, with a particular hope that ferroelectric solids and polymers can be constructed— materials having spontaneous electric polarization that can be reversed by an electric field. Such materials could lead to new low-cost memory devices for computers. The fine control of dispersed magnetic nanostructures will take the storage and tunability of magnetic media to new levels, and novel tunneling microscopy approaches allow measurement of microscopic hysteresis effects in iron nanowires. 

Nitrogen-containing explosives [249] and trinitrotoluene [250] have been determined in soil by gas chromatography with thermionic NP detection and reverse-phase high-performance liquid chromatography. Warmont et al. [251] used tunable infrared laser detection to study the pyrolysis products of explosives in soil. 

The PR effect was first observed in 1966 as an undesirable effect in an EO crystal, LiNb03 [1], It was soon realized that this effect is reversible and its PR mechanism was then identified [2,3], These PR materials can be applied to high-capacity optical memories, dynamic hologram formations, massive interconnections, high-speed tunable filters, and true-time relay lines for phase array... 

Rejections of other ions besides Na+ and Cl- are tunable characteristics of the reverse osmosis membranes that depend upon the intrinsic nature of polymer separating layer and how it has been processed. In general, bivalent ions like Ca2+ and SO4- are more easily rejected than are monovalent ones like Na+ and Cl-. 

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