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Search Publications by: John Barker (Fed)

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Displaying 1 - 25 of 46

Antivesiculation and Complete Unbinding of Tail-Tethered Lipids

January 8, 2024
Author(s)
Kuo-Chih Shih, Geoffray Leriche, Chung-Hao Liu, Jibao He, Vijay John, John Barker, Michihiro Nagao, Lin Yang, Jerry Yang, Mu-Ping Nieh
We report the effect of tail-tethering on vesiculation and complete unbinding of bilayered membranes. Amphiphilic molecules of a bolalipid, resembling the tail-tethered molecular structure of archaeal lipids, with two identical zwitterionic

Facile Polymerization in a Bicellar Template to Produce Polymer Nano-Rings

January 15, 2023
Author(s)
Chung-Hao Liu, Catherine Cheu, John Barker, Lin Yang, Mu-Ping Nieh
Hypothesis: A well-defined discoidal bicelle composed of three lipids, specifically zwitterionic long-chain 1,2-dipalmitoyl phosphocholine (DPPC) and short-chain 1,2-dihexanoyl phosphocholine (DHPC) doped with anionic 1,2-dipalmitoyl phosphoglycerol (DPPG)

The Very Small-Angle Neutron Scattering Instrument at the National Institute of Standards and Technology

February 27, 2022
Author(s)
John Barker, James Moyer, Steven Kline, G. Jensen, Jeremy Cook, Cedric V. Gagnon, Elizabeth Kelley, Jean Philippe Chabot, Nicholas C. Maliszewskyj, Chirag B. Parikh, Wangchun Chen, C. Glinka
A description and the performance of the Very Small-Angle Neutron Scattering (VSANS) Diffractometer at the National Institute of Standards and Technology are presented. The measurement range of the instrument extends over three decades of momentum transfer

Spin-Analyzed SANS for Soft Matter Applications

June 20, 2017
Author(s)
WangChun Chen, John Barker, Ronald L. Jones, Kathryn Krycka, Shannon Watson, Cedric Victor Lucien Gagnon, T. Perevozchivoka, Paul Butler, Thomas R. Gentile
The small angle neutron scattering (SANS) of nearly Q-independent nuclear spin-incoherent scattering from hydrogen present in most soft matter and biology samples may raise an issue in structure determination in certain soft matter applications. This is

Comparison of Pinhole Collimation and Focusing Optics for SANS

September 21, 2015
Author(s)
Charles J. Glinka, John G. Barker, David F. Mildner
We examine quantitatively the instrumental factors that affect the theoretical performance and practical application of conventional pinhole collimation and focusing optics for Small-Angle Neutron Scattering (SANS) measurements. We calculate the relative