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Interhelical Spacing in Liquid Crystalline Spermine and Spermidine-DNA Precipitates
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ABSTRACT
The structure of polyamines-DNA precipitates was studied by x-ray diffraction. Precise measurements of the interhelix distance a^sub H^ were obtained at different NaCl, polyamine, and DNA concentrations. Most of the results were obtained using spermine and few others using spermidine. The precipitates are liquid crystalline, either hexagonal and/or cholesteric, with an interhelical spacing that depends on the ionic concentrations and on the polyamine type. In our experimental ...
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Polymer Engineering and Science
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Polymer Engineering and Science
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Polymer Engineering and Science
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Research and Markets Adds Report: Photoalignment of Liquid Crystalline Materials: Physics and Applications
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Polymer Engineering and Science
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Polymer Engineering and Science
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Structures and tensile properties of a magnetically and mechanically oriented liquid crystalline copolyester, Xydar.
Polymer Engineering and Science
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