skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Magnetic Nanocomposites and Their Incorporation into Higher Order Biosynthetic Functional Architectures

Authors:
ORCiD logo [1];  [2];  [3];  [4]; ORCiD logo [1]
  1. Center for Integrated Nanotechnologies, Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, United States
  2. Department of Chemistry, Southern New Hampshire University, 2500 North River Road, Hooksett, New Hampshire 03106, United States
  3. Imagion Biosystems, 800 Bradbury Drive SE, Albuquerque, New Mexico 87106, United States
  4. Department of Chemistry &, Biochemistry, Northern Arizona University, South San Francisco Street, Flagstaff, Arizona 86011, United States
Publication Date:
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1417217
Grant/Contract Number:
SC0001035
Resource Type:
Journal Article: Published Article
Journal Name:
ACS Omega
Additional Journal Information:
Journal Volume: 3; Journal Issue: 1; Related Information: CHORUS Timestamp: 2018-01-17 07:30:09; Journal ID: ISSN 2470-1343
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
English

Citation Formats

Watt, John, Collins, Aaron M., Vreeland, Erika C., Montano, Gabriel A., and Huber, Dale L. Magnetic Nanocomposites and Their Incorporation into Higher Order Biosynthetic Functional Architectures. United States: N. p., 2018. Web. doi:10.1021/acsomega.7b02031.
Watt, John, Collins, Aaron M., Vreeland, Erika C., Montano, Gabriel A., & Huber, Dale L. Magnetic Nanocomposites and Their Incorporation into Higher Order Biosynthetic Functional Architectures. United States. doi:10.1021/acsomega.7b02031.
Watt, John, Collins, Aaron M., Vreeland, Erika C., Montano, Gabriel A., and Huber, Dale L. 2018. "Magnetic Nanocomposites and Their Incorporation into Higher Order Biosynthetic Functional Architectures". United States. doi:10.1021/acsomega.7b02031.
@article{osti_1417217,
title = {Magnetic Nanocomposites and Their Incorporation into Higher Order Biosynthetic Functional Architectures},
author = {Watt, John and Collins, Aaron M. and Vreeland, Erika C. and Montano, Gabriel A. and Huber, Dale L.},
abstractNote = {},
doi = {10.1021/acsomega.7b02031},
journal = {ACS Omega},
number = 1,
volume = 3,
place = {United States},
year = 2018,
month = 1
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1021/acsomega.7b02031

Save / Share:
  • Abstract not provided.
  • The complex of MukF, MukE, and MukB proteins participates in organization of sister chromosomes and partitioning into both daughter cells in Escherichia coli. We purified the MukB homodimer and the MukBEF complex and analyzed them by electron microscopy to compare both structures. A MukB homodimer shows a long rod-hinge-rod v-shape with small globular domains at both ends. The MukBEF complex shows a similar structure having larger globular domains than those of the MukB homodimer. These results suggest that MukF and MukE bind to the globular domains of a MukB homodimer. The globular domains of the MukBEF complex frequently associate withmore » each other in an intramolecular fashion, forming a ring. In addition, MukBEF complex molecules tend to form multimers by the end-to-end joining with other MukBEF molecules in an intermolecular fashion, resulting in fibers and rosette-form structures in the absence of ATP and DNA in vitro.« less
  • In the present work, we study various numerical aspects of higher-order finite-element discretizations of the non-linear saddle-point formulation of orbital-free density-functional theory. We first investigate the robustness of viable solution schemes by analyzing the solvability conditions of the discrete problem. We find that a staggered solution procedure where the potential fields are computed consistently for every trial electron-density is a robust solution procedure for higher-order finite-element discretizations. We next study the convergence properties of higher-order finite-element discretizations of orbital-free density functional theory by considering benchmark problems that include calculations involving both pseudopotential as well as Coulomb singular potential fields. Ourmore » numerical studies suggest close to optimal rates of convergence on all benchmark problems for various orders of finite-element approximations considered in the present study. We finally investigate the computational efficiency afforded by various higher-order finite-element discretizations, which constitutes the main aspect of the present work, by measuring the CPU time for the solution of discrete equations on benchmark problems that include large Aluminum clusters. In these studies, we use mesh coarse-graining rates that are derived from error estimates and an a priori knowledge of the asymptotic solution of the far-field electronic fields. Our studies reveal a significant 100-1000 fold computational savings afforded by the use of higher-order finite-element discretization, alongside providing the desired chemical accuracy. We consider this study as a step towards developing a robust and computationally efficient discretization of electronic structure calculations using the finite-element basis.« less
  • We present an efficient computational approach to perform real-space electronic structure calculations using an adaptive higher-order finite-element discretization of Kohn–Sham density-functional theory (DFT). To this end, we develop an a priori mesh-adaption technique to construct a close to optimal finite-element discretization of the problem. We further propose an efficient solution strategy for solving the discrete eigenvalue problem by using spectral finite-elements in conjunction with Gauss–Lobatto quadrature, and a Chebyshev acceleration technique for computing the occupied eigenspace. The proposed approach has been observed to provide a staggering 100–200-fold computational advantage over the solution of a generalized eigenvalue problem. Using the proposedmore » solution procedure, we investigate the computational efficiency afforded by higher-order finite-element discretizations of the Kohn–Sham DFT problem. Our studies suggest that staggering computational savings—of the order of 1000-fold—relative to linear finite-elements can be realized, for both all-electron and local pseudopotential calculations, by using higher-order finite-element discretizations. On all the benchmark systems studied, we observe diminishing returns in computational savings beyond the sixth-order for accuracies commensurate with chemical accuracy, suggesting that the hexic spectral-element may be an optimal choice for the finite-element discretization of the Kohn–Sham DFT problem. A comparative study of the computational efficiency of the proposed higher-order finite-element discretizations suggests that the performance of finite-element basis is competing with the plane-wave discretization for non-periodic local pseudopotential calculations, and compares to the Gaussian basis for all-electron calculations to within an order of magnitude. Further, we demonstrate the capability of the proposed approach to compute the electronic structure of a metallic system containing 1688 atoms using modest computational resources, and good scalability of the present implementation up to 192 processors.« less