Studies Toward the Synthesis of Phenylacetylene Macrocycle Based Rotaxane Precursors as Building Blocks for Organic Nanotubes

2012 ◽  
Vol 2012 (27) ◽  
pp. 5335-5349 ◽  
Author(s):  
Katy Cantin ◽  
Antoine Lafleur-Lambert ◽  
Philippe Dufour ◽  
Jean-François Morin
Keyword(s):  
Building Blocks ◽  
Organic Nanotubes

scholarly journals Microfluidics for the rapid and controlled preparation of organic nanotubes of bent-core based dendrimers

2021 ◽  
Author(s):  
M. Blanca Ros ◽  
Martín Castillo-Vallés ◽  
Pilar Romero ◽  
Victor Sebastian
Keyword(s):  
Building Blocks ◽  
Microfluidic System ◽  
Promising Tool ◽  
Organic Nanotubes ◽  
Controlled Preparation

Recently, bent-core molecules have arised as excellent building blocks for the obtaining of nanostructures in solvents. Herein, we report the use of a coaxial microfluidic system as a promising tool...

Helical Organic Nanotubes from Simple Chiral Building Blocks

2013 ◽  
Vol 13 (10) ◽  
pp. 6961-6966
Author(s):  
Wei Wei ◽  
Kun Huang ◽  
Chih-Ning Pao ◽  
Zuming Hu ◽  
Yunfeng Lu
Keyword(s):  
Building Blocks ◽  
Organic Nanotubes

ATOMISTIC MODELING AND MECHANICS OF SELF-ASSEMBLED ORGANIC NANOTUBES

2011 ◽  
Vol 03 (04) ◽  
pp. 667-684 ◽  
Author(s):  
LUIS RUIZ ◽  
SINAN KETEN
Keyword(s):  
Hydrogen Bonds ◽  
Large Scale ◽  
Shear Failure ◽  
Cyclic Peptide ◽  
Building Blocks ◽  
Great Promise ◽  
Deformation And Failure ◽  
Self Assembling ◽  
Self Assembled ◽  
Organic Nanotubes

Organic building blocks inspired by biological systems are promising for fabricating nanostructured materials for a broad range of applications such as antimicrobials, biosensors, electronics, and biomaterials. Self-assembling cyclic peptide organic nanotubes have shown great promise for these applications due to their precise structural features, diverse chemical functionalization capabilities and exceptional stability arising from arrangement of hydrogen bonds into cooperative clusters. Mechanical behavior of organic nanotubes is important for various possible applications ranging from subnanoporous selective membranes to molecular templates for electronics. However, large-scale deformation mechanisms of organic nanotubes have not been studied thus far. Here we investigate the mechanisms involved in the large deformation and failure of self-assembled organic nanotubes, focusing on geometry effects characteristic of protein nanostructures. We carry out molecular dynamics simulations to assess the role of hydrogen bonds as weak interactions in the context of deformation and failure processes involving bending and shear loads. Mechanisms of failure are found to depend on the cross-sectional geometry and the deformation rate, where a transition to localized shear failure is observed at high-strain rates. Our results provide important physical insight into the mechanics of organic nanotubes central to emerging applications of self-assembling peptides in biomedicine and biotechnology.

Photochemical Evolution of Interstellar/Precometary Organic Material

1997 ◽  
Vol 161 ◽  
pp. 23-47 ◽  
Author(s):  
Louis J. Allamandola ◽  
Max P. Bernstein ◽  
Scott A. Sandford
Keyword(s):  
Origin Of Life ◽  
Building Blocks ◽  
Complex Species ◽  
Infrared Observations ◽  
Interstellar Ice ◽  
Polycyclic Aromatic ◽  
Ultraviolet Photolysis ◽  
The Origin Of Life ◽  
Simple Molecules ◽  
Complex Organic

AbstractInfrared observations, combined with realistic laboratory simulations, have revolutionized our understanding of interstellar ice and dust, the building blocks of comets. Since comets are thought to be a major source of the volatiles on the primative earth, their organic inventory is of central importance to questions concerning the origin of life. Ices in molecular clouds contain the very simple molecules H2O, CH3OH, CO, CO2, CH4, H2, and probably some NH3and H2CO, as well as more complex species including nitriles, ketones, and esters. The evidence for these, as well as carbonrich materials such as polycyclic aromatic hydrocarbons (PAHs), microdiamonds, and amorphous carbon is briefly reviewed. This is followed by a detailed summary of interstellar/precometary ice photochemical evolution based on laboratory studies of realistic polar ice analogs. Ultraviolet photolysis of these ices produces H2, H2CO, CO2, CO, CH4, HCO, and the moderately complex organic molecules: CH3CH2OH (ethanol), HC(= O)NH2(formamide), CH3C(= O)NH2(acetamide), R-CN (nitriles), and hexamethylenetetramine (HMT, C6H12N4), as well as more complex species including polyoxymethylene and related species (POMs), amides, and ketones. The ready formation of these organic species from simple starting mixtures, the ice chemistry that ensues when these ices are mildly warmed, plus the observation that the more complex refractory photoproducts show lipid-like behavior and readily self organize into droplets upon exposure to liquid water suggest that comets may have played an important role in the origin of life.

Laboratory and in-situ analysis of comet dust

1988 ◽  
Vol 46 ◽  
pp. 8-9
Author(s):  
D.E. Brownlee ◽  
A.L. Albee
Keyword(s):  
Electron Microscopy ◽  
Solar System ◽  
Laboratory Study ◽  
Isotopic Analysis ◽  
Building Blocks ◽  
Sem Analysis ◽  
Early Solar System ◽  
Cometary Material ◽  
Comet Dust

Comets are primitive, kilometer-sized bodies that formed in the outer regions of the solar system. Composed of ice and dust, comets are generally believed to be relic building blocks of the outer solar system that have been preserved at cryogenic temperatures since the formation of the Sun and planets. The analysis of cometary material is particularly important because the properties of cometary material provide direct information on the processes and environments that formed and influenced solid matter both in the early solar system and in the interstellar environments that preceded it.The first direct analyses of proven comet dust were made during the Soviet and European spacecraft encounters with Comet Halley in 1986. These missions carried time-of-flight mass spectrometers that measured mass spectra of individual micron and smaller particles. The Halley measurements were semi-quantitative but they showed that comet dust is a complex fine-grained mixture of silicates and organic material. A full understanding of comet dust will require detailed morphological, mineralogical, elemental and isotopic analysis at the finest possible scale. Electron microscopy and related microbeam techniques will play key roles in the analysis. The present and future of electron microscopy of comet samples involves laboratory study of micrometeorites collected in the stratosphere, in-situ SEM analysis of particles collected at a comet and laboratory study of samples collected from a comet and returned to the Earth for detailed study.

Cryo-TEM of amphiphilic polymer and amphiphile/polymer solutions

1993 ◽  
Vol 51 ◽  
pp. 876-877
Author(s):  
Yeshayahu Talmon
Keyword(s):  
Microstructural Characterization ◽  
Building Blocks ◽  
Quantitative Information ◽  
Physical Models ◽  
Specimen Preparation ◽  
Time Resolved ◽  
Temperature Changes ◽  
Temperature And Humidity ◽  
Microstructured Fluids ◽  
Air Streams

To achieve complete microstructural characterization of self-aggregating systems, one needs direct images in addition to quantitative information from non-imaging, e.g., scattering or Theological measurements, techniques. Cryo-TEM enables us to image fluid microstructures at better than one nanometer resolution, with minimal specimen preparation artifacts. Direct images are used to determine the “building blocks” of the fluid microstructure; these are used to build reliable physical models with which quantitative information from techniques such as small-angle x-ray or neutron scattering can be analyzed.To prepare vitrified specimens of microstructured fluids, we have developed the Controlled Environment Vitrification System (CEVS), that enables us to prepare samples under controlled temperature and humidity conditions, thus minimizing microstructural rearrangement due to volatile evaporation or temperature changes. The CEVS may be used to trigger on-the-grid processes to induce formation of new phases, or to study intermediate, transient structures during change of phase (“time-resolved cryo-TEM”). Recently we have developed a new CEVS, where temperature and humidity are controlled by continuous flow of a mixture of humidified and dry air streams.

Emotional Variability Predicts Tiredness in Daily Life

2016 ◽  
Vol 37 (3) ◽  
pp. 181-193 ◽  
Author(s):  
Aire Mill ◽  
Anu Realo ◽  
Jüri Allik
Keyword(s):  
Sampling Method ◽  
Daily Life ◽  
Emotional Experience ◽  
Experience Sampling ◽  
Experience Sampling Method ◽  
Building Blocks ◽  
Intraindividual Variability ◽  
Unique Role ◽  
Over Time

Abstract. Intraindividual variability, along with the more frequently studied between-person variability, has been argued to be one of the basic building blocks of emotional experience. The aim of the current study is to examine whether intraindividual variability in affect predicts tiredness in daily life. Intraindividual variability in affect was studied with the experience sampling method in a group of 110 participants (aged between 19 and 84 years) during 14 consecutive days on seven randomly determined occasions per day. The results suggest that affect variability is a stable construct over time and situations. Our findings also demonstrate that intraindividual variability in affect has a unique role in predicting increased levels of tiredness at the momentary level as well at the level of individuals.

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