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Macroscopic orientation of self-organized supramolecular polymeric materials has been demonstrated by oscillatory shear flow using in-situ small-angle X-ray scattering (SAXS). In the case when a homopolymer poly(4-vinylpyridine) and pentadecylphenol molecules are stoichiometrically complexed to form comb copolymer-like supermolecules, the self-organized lamellar local structures align parallel when sheared below the order-disorder transition temperature at 56 °C using 0.5 Hz frequency and 100% strain amplitude. Therefore, the hydrogen bonds between the phenolic and pyridine groups are strong enough to withstand the applied flow. In the case of a diblock copolymer of polystyrene and poly(4-vinylpyridine) stoichiometrically complexed with pentadecylphenol molecules to form the supermolecules, the self-organization yields lamellar-within-lamellar local structure near room temperature. The larger lamellar diblock copolymer structure showed a parallel orientation relative to the shearing plates upon shearing at 125 °C (i.e., above the order-disorder transition of the short length scale comb copolymer-like structure) with initially 0.5 Hz and finally 1 Hz, both at 50% strain amplitude. On cooling, the short length scale lamellar structure, consisting of poly(4-vinylpyridine) block and pentadecylphenol, is formed inside the layers of the comb copolymer-like material in perpendicular orientation.

It was demonstrated that polymeric supramolecular nanostructures with several length scales allow straightforward tailoring of hierarchical order-disorder and order-order transitions and the concurrent switching of functional properties. Poly(4-vinyl pyridine) (P4VP) was stoichiometrically protonated with methane sulfonic acid (MSA) to form P4VP(MSA) 1.0 , which was then hydrogen-bonded to pentadecylphenol. Microphase separation, re-entrant closed-loop macrophase separation, and high-temperature macrophase separation were observed. When MSA and pentadecylphenol were complexed to the P4VP block of a microphase-separated diblock copolymer poly[styrene- block -(4-vinyl pyridine)], self-organized structures-in-structures were obtained whose hierarchical phase transitions can be controlled systematically. This microstructural control on two different length scales (in the present case, at 48 and 350 angstroms) was then used to introduce temperature-dependent transitions in electrical conductivity.

This paper reviews paraprofessional employment in libraries and examines the trend toward assigning increasingly complex duties to academic library paraprofessionals. During the spring of 1989, directors of academic health sciences libraries in the United States and Canada were surveyed to determine the duties assigned to paraprofessionals. The results show that paraprofessionals are assigned a wide range of duties, including supervising functional areas, such as circulation and interlibrary loan, and some tasks often considered professional, such as original cataloging and in-depth reference work. The findings illustrate the importance of the paraprofessional to librarianship.

We propose a two-fold approach to model reduction of fluid-structure interaction. The state equations for the fluid are solved with reduced basis methods. These are model reduction methods for parametric partial differential equations using well-chosen snapshot solutions in order to build a set of global basis functions. The other reduction is in terms of the geometric complexity of the moving fluidstructure interface. We use free-form deformations to parameterize the perturbation of the flow channel at rest configuration. As a computational example we consider a steady fluid-structure interaction problem: an incompressible Stokes flow in a channel that has a flexible wall.