Tuning the surface energies in a family of poly-3-alkylthiophenes bearing hydrophilic side-chains synthesized via direct arylation polymerization (DArP)

2021 ◽  
Author(s):  
Alexander Schmitt ◽  
Sanket Samal ◽  
Barry C. Thompson
Keyword(s):  
Surface Energy ◽  
Electronic Properties ◽  
Functional Groups ◽  
Functional Group ◽  
Side Chains ◽  
Direct Arylation ◽  
Surface Energies ◽  
Direct Arylation Polymerization

A family of Poly(3-alkylthiophene) copolymers bearing different functional groups was synthesized via direct arylation polymerization and the functional group impact on surface energy, crystallinity, and electronic properties was investigated.

Surface energies and electronic properties of intermetallic compound B2-AgMg

2019 ◽  
Vol 33 (08) ◽  
pp. 1950097
Author(s):  
Jing-Bo Sun ◽  
Jian-Gang Yao ◽  
Jiang Meng ◽  
Shuping Li ◽  
Yong Jiang ◽  
...  
Keyword(s):  
Intermetallic Compound ◽  
Surface Energy ◽  
Electronic Properties ◽  
Surface Analysis ◽  
Chemical Potential ◽  
New Method ◽  
Surface Energies ◽  
Surface Models

A new method was used to predict the surface energies of three low-index surfaces for intermetallic compound B2-AgMg. The results show that Ag-terminal and Mg-terminal are the two kinds of surface models for (1 0 0) and (1 1 1) surfaces which are non-stoichiometry. (1 1 0) surface has only one surface terminal, which is stoichiometry, and the smallest surface energy (about [Formula: see text] in three low-index surfaces. The surface energies are related to the chemical potential of Ag and Mg atoms for (1 0 0) and (1 1 1) surfaces, but it is of no concern to this factor for stoichiometry (1 1 0) surface. Analysis of electronic properties is coincident with the calculated surface energies.

scholarly journals Evolution Mechanism of Metallic Dioxide MO2 (M = Mn, Ti) from Nanorods to Bulk Crystal: First-Principles Research

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Pengsen Zhao ◽  
Guifa Li ◽  
Bingtian Li ◽  
Haizhong Zheng ◽  
Shiqiang Lu ◽  
...  
Keyword(s):  
Surface Energy ◽  
Electronic Properties ◽  
Surface Effect ◽  
Mulliken Charge ◽  
Mulliken Population ◽  
Evolution Mechanism ◽  
Surface Energies ◽  
Surface Areas ◽  
Nanometer Materials ◽  
Intrinsic Mechanism

Using first-principle calculations, the surface energy, cohesive energy, and electronic properties of α-MnO2 and rutile TiO2 nanorods and microfacets were investigated and clarified to, in the first instance, determine the evolution mechanism. The results show that the surface energies of α-MnO2 nanorods and microfacets conform to function 1.0401 Jm−2 + N × 0.608 Jm−2, while the surface energies of the rutile TiO2 nanorods and microfacets are governed by a 1.0102 × 1.1997 rule. Their electronic properties, such as the Mulliken population and Mulliken charge, can only be normalized by their surface areas to attain a linear function. Meanwhile, the surface energy of α-MnO2 with the nanostructure closely conforms to the function for normalized Mulliken population and Mulliken charge as f(x)=102.9×x+0.101 with an R2 value of 0.995. Thus, our research into the evolution mechanism affecting the surface effect of nanometer materials will be useful for investigating the intrinsic mechanism of the nanometer effect and doping process of metallic dioxide catalysts.

A Strategy for Thioamide Incorporation During Fmoc Solid-Phase Peptide Synthesis with Robust Stereochemical Integrity

2019 ◽  
Author(s):  
luis camacho III ◽  
Bryan J. Lampkin ◽  
Brett VanVeller
Keyword(s):  
Amino Acid ◽  
Functional Groups ◽  
Peptide Synthesis ◽  
Solid Phase ◽  
Solid Phase Peptide Synthesis ◽  
Side Chains ◽  
Amino Acid Side Chains ◽  
Peptide Elongation

We describe a method to protect the sensitive stereochemistry of the thioamide—in analogy to the protection of the functional groups of amino acid side chains—in order to preserve the thioamide moiety during peptide elongation.<br>

Influence of synthetic pathway, molecular weight and side chains on properties of indacenodithiophene-benzothiadiazole copolymers made by direct arylation polycondensation

2021 ◽  
Vol 9 (13) ◽  
pp. 4597-4606
Author(s):  
Desiree Adamczak ◽  
Andrea Perinot ◽  
Hartmut Komber ◽  
Anna Illy ◽  
Sandra Hultmark ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Side Chains ◽  
Direct Arylation ◽  
Synthetic Pathway ◽  
Direct Arylation Polycondensation

Poly(indacenodithiophene-alt-benzothiadiazole) with different side chains and molecular weight is made using two different pathways in which all C–C coupling steps are achieved by C–H activation, and the products are comprehensively investigated.

scholarly journals Resilience of Epiphytic Lichens to Combined Effects of Increasing Nitrogen and Solar Radiation

2021 ◽  
Vol 7 (5) ◽  
pp. 333
Author(s):  
Lourdes Morillas ◽  
Javier Roales ◽  
Cristina Cruz ◽  
Silvana Munzi
Keyword(s):  
Global Change ◽  
Solar Radiation ◽  
Functional Groups ◽  
Physiological Response ◽  
Functional Group ◽  
Environmental Drivers ◽  
Combined Effects ◽  
Environmental Stressor ◽  
Comprehensive Understanding ◽  
Direct Sunlight

Lichens are classified into different functional groups depending on their ecological and physiological response to a given environmental stressor. However, knowledge on lichen response to the synergistic effect of multiple environmental factors is extremely scarce, although vital to get a comprehensive understanding of the effects of global change. We exposed six lichen species belonging to different functional groups to the combined effects of two nitrogen (N) doses and direct sunlight involving both high temperatures and ultraviolet (UV) radiation for 58 days. Irrespective of their functional group, all species showed a homogenous response to N with cumulative, detrimental effects and an inability to recover following sunlight, UV exposure. Moreover, solar radiation made a tolerant species more prone to N pollution’s effects. Our results draw attention to the combined effects of global change and other environmental drivers on canopy defoliation and tree death, with consequences for the protection of ecosystems.

scholarly journals Vertical Orientation of Liquid Crystal on 4-n-Alkyloxyphenoxymethyl-Substituted Polystyrene Containing Liquid Crystal Precursor

Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 736
Author(s):  
Kyutae Seo ◽  
Hyo Kang
Keyword(s):  
Molecular Structure ◽  
Liquid Crystal ◽  
Surface Energy ◽  
Polymer Films ◽  
Ultraviolet Irradiation ◽  
Molar Fraction ◽  
Side Chain ◽  
Polymer Modification ◽  
Vertical Orientation ◽  
Surface Energies

We synthesized a series of polystyrene derivatives that were modified with precursors of liquid crystal (LC) molecules, such as 4-ethyloxyphenol (homopolymer PEOP and copolymer PEOP#; # = 20, 40, 60, and 80, where # indicates the molar fraction of 4-ethyloxyphenoxymethyl in the side chain), 4-n-butyloxyphenol (PBOP), 4-n-hexyloxyphenol (PHOP), and 4-n-octyloxyphenol (POOP), via polymer modification reaction to investigate the orientation of LC molecules on polymer films, exhibiting part of the LC molecular structure. LC molecules showed a stable and uniform vertical orientation in LC cells fabricated with polymers that have 4-ethyloxyphenoxymethyl in the range of 40–100 mol%. In addition, similar results were obtained in LC cells fabricated with homopolymers of PEOP, PBOP, PHOP, and POOP. The vertical orientation of LC molecules in LC cells fabricated with polymer films correlated to the surface energy of polymer films. For example, vertical LC orientation was observed when the total surface energies of the polymer films were lower than approximately 43.2 mJ/m2. Good alignment stabilities were observed at 150 °C and 20 J/cm2 of ultraviolet irradiation for LC cells fabricated with PEOP film.

The action of rennin on casein: the effect of modifying functional groups on the casein

1965 ◽  
Vol 32 (2) ◽  
pp. 193-201 ◽  
Author(s):  
R. D. Hill ◽  
Raione R. Laing
Keyword(s):  
Methylene Blue ◽  
Amino Acid ◽  
Functional Groups ◽  
Amino Acid Analysis ◽  
Side Chains ◽  
Photo Oxidation

Summaryk-Casein and whole casein when photo-oxidized in the presence of methylene blue lose the ability to clot when treated with rennin. Two effects are involved—first the photo-oxidation alters the k-casein fraction so that the rennin is unable to split off the glycopeptide fragment, and secondly, in whole casein the photo-oxidation interferes with the aggregation in the presence of Ca++that normally follows rennin action. As a result of amino acid analysis and specific treatments which affect other photo-oxidizable side chains, it is concluded that both of these effects are caused by the alteration of histidines.

SURFACE ENERGY ENGINEERING OF Cu SURFACE BY STRAIN: FIRST-PRINCIPLES CALCULATIONS

2013 ◽  
Vol 20 (06) ◽  
pp. 1350054 ◽  
Author(s):  
L. HE ◽  
Y. W. LIU ◽  
W. J. TONG ◽  
J. G. LIN ◽  
X. F. WANG
Keyword(s):  
Surface Energy ◽  
First Principles ◽  
Strain Distribution ◽  
First Principles Calculations ◽  
Surface Energies ◽  
Energy Engineering

Surface energies of strained Cu surfaces were studied systematically using first-principles methods. Results showed that the strain-stabilization of Cu surface was anisotropic and strongly related to the strain distribution. This strain-induced approach could be used as an effective way to engineer the surface energies of metals.

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