SYNOPSISNylon-11 polymorphs have been studied by x-ray diffraction and by infrared spectroscopy. A y or y-like phase of Nylon-11 was produced by treating the metastable 6' phase with gaseous HC1 or DC1 and then exposing the resulting complex (amidonium salt) to 100% RH H20 or D20 vapor. An oriented form of the y or y-like phase results from treatment of the oriented 6' phase, but stretching of the unoriented y or y-like phase, obtained by treatment of the unoriented 6' phase, induces a transformation to the a phase stable at room temperature. The use of DCl and D20 produced highly deuterated samples with Fermi resonances indicating the relative strengths of the hydrogen bonds are weakest in the a phase, intermediate in the 6'phase and strongest in the y or y-like phase. 0 1994 John Wiley & Sons, Inc.

High‐temperature superconducting (HTS) power equipment has the potential to become a key 21st century technology for improving the capacity, efficiency, and reliability of the electric delivery system. For example, higher‐capacity HTS power lines could provide a new approach to building transmission and distribution systems that will reduce the footprint and allow additional capacity to be placed in service within existing rights‐of‐way. The U.S. Department of Energy has supported HTS research and development for almost 20 years. Two of its recent cable projects have been commissioned and are now powering over the equivalent of more than 61,000 homes.

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