scholarly journals Silk Self-Assembly Mechanisms and Control From Thermodynamics to Kinetics

2012 ◽  
Vol 13 (3) ◽  
pp. 826-832 ◽  
Author(s):  
Qiang Lu ◽  
Hesun Zhu ◽  
Cencen Zhang ◽  
Feng Zhang ◽  
Bing Zhang ◽  
...  
Keyword(s):  
Self Assembly ◽  
And Control

Kinetic Control of Interpenetration in Fe-Biphenyl-4,4′-dicarboxylate MOFs by Coordination and Oxidation Modulation

2018 ◽  
Author(s):  
Dominic Bara ◽  
Claire Wilson ◽  
Max Mörtel ◽  
Marat M. Khusniyarov ◽  
ben slater ◽  
...  
Keyword(s):  
Self Assembly ◽  
Surface Areas ◽  
Metal Precursors ◽  
Additional Coordination ◽  
Fine Control ◽  
Multiple Alternative ◽  
Metal Organic ◽  
Dft Simulations ◽  
High Valent ◽  
And Control

Phase control in the self-assembly of metal-organic frameworks (MOFs) – materials wherein organic ligands connect metal ions or clusters into network solids with potential porosity – is often a case of trial and error. Judicious control over a number of synthetic variables is required to select for the desired topology and control features such as interpenetration and defectivity, which have significant impact on physical properties and application. Herein, we present a comprehensive investigation of self-assembly in the Fe-biphenyl-4,4'-dicarboxylate system, demonstrating that coordination modulation, the addition of competing ligands into solvothermal syntheses, can reliably tune between the kinetic product, non-interpenetrated MIL-88D(Fe), and the thermodynamic product, two-fold interpenetrated MIL-126(Fe). DFT simulations reveal that correlated disorder of the terminal anions on the metal clusters in the interpentrated phase results in H-bonding between adjacent nets and is the thermodynamic driving force for its formation. Coordination modulation slows self-assembly and therefore selects the thermodynamic product MIL-126(Fe), while offering fine control over defectivity, inducing mesoporosity, but electron microscopy shows the MIL-88D(Fe) phase persists in many samples despite not being evident in diffraction experiments, suggesting its presence accounts for the lower than predicted surface areas reported for samples to date. Interpenetration control is also demonstrated by utilizing the 2,2'-bipyridine-5,5'-dicarboxylate linker; DFT simulations show that it is energetically prohibitive for it to adopt the twisted conformation required to form the interpenetrated phase, and are confirmed by experimental data, although multiple alternative phases are identified due to additional coordination of the Fe cations to the N-donors of the ligand. Finally, we introduce oxidation modulation – the concept of using metal precursors in a different oxidation state to that found in the final MOF – as a further protocol to kinetically control self-assembly. Combining coordination and oxidation modulation allows the synthesis of pristine MIL-126(Fe) with BET surface areas close to the predicted maximum capacity for the first time, suggesting that combining the two may be a powerful methodology for the controlled self-assembly of high-valent MOFs.<br><br>

scholarly journals Guided Self-Assembly and Control of Vortices in Ensembles of Active Magnetic Rollers

Langmuir ◽  
2019 ◽  
Vol 36 (25) ◽  
pp. 6957-6962 ◽  
Author(s):  
Gašper Kokot ◽  
Andrey Sokolov ◽  
Alexey Snezhko
Keyword(s):  
Self Assembly ◽  
And Control

Structure and Self-Assembly of Multicolored Naphthalene Diimides Semiconductor

Nano LIFE ◽  
2016 ◽  
Vol 06 (03n04) ◽  
pp. 1642007
Author(s):  
Zhili Yao ◽  
Yuan Sun ◽  
Chen Kang
Keyword(s):  
Self Assembly ◽  
Optoelectronic Devices ◽  
Supramolecular Interactions ◽  
Promising Candidate ◽  
One Dimensional ◽  
Ordered Nanostructures ◽  
The One ◽  
Naphthalene Diimides ◽  
And Control ◽  
New Strategies

The one-dimensional (1D) self-assembly of [Formula: see text]-electron molecules offers efficient strategies to enhance energy and charge transfer via highly ordered and conductive [Formula: see text] stacking of the chromophores. The chromophore rich nanostructures have great potential to serve as promising candidate materials for optoelectronic devices. However, the design and control of highly ordered nanostructures with multicolored chromophore redox gradients require finely chosen synthetic strategies and a delicate balance of supramolecular interactions. In this paper, we will introduce new strategies focused on self-assembly of nanofibers based on lysine derivatives functionalized with multi colored chromophores.

scholarly journals Readout and control of an endofullerene electronic spin

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Dinesh Pinto ◽  
Domenico Paone ◽  
Bastian Kern ◽  
Tim Dierker ◽  
René Wieczorek ◽  
...  
Keyword(s):  
Self Assembly ◽  
Large Scale ◽  
Dipolar Interaction ◽  
Nitrogen Vacancy ◽  
Zero Field ◽  
Zero Field Splitting ◽  
Paramagnetic Resonance ◽  
Near Surface ◽  
Atomic Spins ◽  
And Control

AbstractAtomic spins for quantum technologies need to be individually addressed and positioned with nanoscale precision. C60 fullerene cages offer a robust packaging for atomic spins, while allowing in-situ physical positioning at the nanoscale. However, achieving single-spin level readout and control of endofullerenes has so far remained elusive. In this work, we demonstrate electron paramagnetic resonance on an encapsulated nitrogen spin (14N@C60) within a C60 matrix using a single near-surface nitrogen vacancy (NV) center in diamond at 4.7 K. Exploiting the strong magnetic dipolar interaction between the NV and endofullerene electronic spins, we demonstrate radio-frequency pulse controlled Rabi oscillations and measure spin-echos on an encapsulated spin. Modeling the results using second-order perturbation theory reveals an enhanced hyperfine interaction and zero-field splitting, possibly caused by surface adsorption on diamond. These results demonstrate the first step towards controlling single endofullerenes, and possibly building large-scale endofullerene quantum machines, which can be scaled using standard positioning or self-assembly methods.

Guidance and control for satellite in-orbit-self-assembly proximity operations

2015 ◽  
Vol 41 ◽  
pp. 289-302 ◽  
Author(s):  
Mohamed Okasha ◽  
Chandeok Park ◽  
Sang-Young Park
Keyword(s):  
Self Assembly ◽  
Proximity Operations ◽  
Guidance And Control ◽  
And Control

Interplay between bulk self-assembly, interfacial and foaming properties in a catanionic surfactant mixture of varying composition

Soft Matter ◽  
2017 ◽  
Vol 13 (39) ◽  
pp. 7197-7206 ◽  
Author(s):  
José Ferreira ◽  
Alesya Mikhailovskaya ◽  
Alexis Chenneviere ◽  
Frédéric Restagno ◽  
Fabrice Cousin ◽  
...  
Keyword(s):  
Self Assembly ◽  
Solution Viscosity ◽  
Foaming Properties ◽  
Mixing Ratio ◽  
Surfactant Mixture ◽  
Catanionic Surfactant ◽  
Bulk Nanostructures ◽  
And Control ◽  
Foam Drainage

Bulk nanostructures and foaming vary markedly with surfactant mixing ratio. Aggregates are unchanged inside foam and control foam drainage through solution viscosity.

scholarly journals Fluid-Mediated Stochastic Self-Assembly at Centimetric and Sub-Millimetric Scales: Design, Modeling, and Control

Micromachines ◽  
2016 ◽  
Vol 7 (8) ◽  
pp. 138 ◽  
Author(s):  
Bahar Haghighat ◽  
Massimo Mastrangeli ◽  
Grégory Mermoud ◽  
Felix Schill ◽  
Alcherio Martinoli
Keyword(s):  
Self Assembly ◽  
Modeling And Control ◽  
And Control

scholarly journals DNA-dependent macromolecular condensation drives self-assembly of the meiotic DNA break machinery

2020 ◽  
Author(s):  
Corentin Claeys Bouuaert ◽  
Stephen Pu ◽  
Juncheng Wang ◽  
Dinshaw J. Patel ◽  
Scott Keeney
Keyword(s):  
Self Assembly ◽  
Chromosome Structure ◽  
Coiled Coil ◽  
Double Strand Breaks ◽  
Dna Double Strand Breaks ◽  
Strand Breaks ◽  
Dna Breakage ◽  
And Control

Formation of meiotic DNA double-strand breaks (DSBs) by Spo11 is tightly regulated and tied to chromosome structure, but the higher-order assemblies that execute and control DNA breakage are poorly understood. We address this question through molecular characterization of Saccharomyces cerevisiae RMM proteins (Rec114, Mei4 and Mer2)—essential, conserved components of the DSB machinery. Each subcomplex of Rec114–Mei4 (2:1 heterotrimer) or Mer2 (homotetrameric coiled coil) is monodisperse in solution, but they independently condense with DNA into dynamic, reversible nucleoprotein clusters that share properties with phase-separated systems. Multivalent interactions drive condensation, which correlates with DSB formation in vivo. Condensates fuse into mixed Rec114–Mei4–Mer2 clusters that further recruit Spo11 complexes. Our data show how the DSB machinery self-assembles on chromosome axes to create centers of DSB activity. We propose that multilayered control of Spo11 arises from recruitment of regulatory components and modulation of biophysical properties of the condensates.

Sign in / Sign up

Export Citation Format

Share Document