scholarly journals Side Chain Motion of Poly(L-glutamate)s Having Long Alkyl Side Chains as Studied by Spin-Probe Technique

1991 ◽  
Vol 23 (1) ◽  
pp. 55-64 ◽  
Author(s):  
Masashi Yamaguchi ◽  
Masao Tezuka ◽  
Akihiro Tsutsumi
Keyword(s):  
Spin Probe ◽  
Side Chain ◽  
Side Chains ◽  
Probe Technique ◽  
Alkyl Side Chains ◽  
Side Chain Motion

scholarly journals Synthesis of New Derivatives of BEDT-TTF: Installation of Alkyl, Ethynyl, and Metal-Binding Side Chains and Formation of Tris(BEDT-TTF) Systems

2021 ◽  
Vol 7 (8) ◽  
pp. 110
Author(s):  
Songjie Yang ◽  
Matteo Zecchini ◽  
Andrew Brooks ◽  
Sara Krivickas ◽  
Desiree Dalligos ◽  
...  
Keyword(s):  
Metal Binding ◽  
Tricarboxylic Acid ◽  
Metal Salts ◽  
Side Chain ◽  
Side Chains ◽  
Ethynyl Group ◽  
X Ray ◽  
Transition Metal Salts ◽  
Alkyl Side Chains ◽  
Derivatives Of

The syntheses of new BEDT-TTF derivatives are described. These comprise BEDT-TTF with one ethynyl group (HC≡C-), with two (n-heptyl) or four (n-butyl) alkyl side chains, with two trans acetal (-CH(OMe)2) groups, with two trans aminomethyl (-CH2NH2) groups, and with an iminodiacetate (-CH2N(CH2CO2−)2 side chain. Three transition metal salts have been prepared from the latter donor, and their magnetic properties are reported. Three tris-donor systems are reported bearing three BEDT-TTF derivatives with ester links to a core derived from benzene-1,3,5-tricarboxylic acid. The stereochemistry and molecular structure of the donors are discussed. X-ray crystal structures of two BEDT-TTF donors are reported: one with two CH(OMe)2 groups and with one a -CH2N(CH2CO2Me)2 side chain.

scholarly journals Controlled steric selectivity in molecular doping towards closest-packed supramolecular conductors

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Shinya Kohno ◽  
Yu Yamashita ◽  
Naotaka Kasuya ◽  
Tsubasa Mikie ◽  
Itaru Osaka ◽  
...  
Keyword(s):  
Conjugated Polymers ◽  
Steric Effects ◽  
Side Chain ◽  
Side Chains ◽  
Void Space ◽  
Alkyl Side Chains ◽  
Recent Developments ◽  
High Carrier ◽  
Molecular Doping ◽  
Steric Selectivity

Abstract Recent developments in molecular doping technologies allow extremely high carrier densities in polymeric semiconductors, exhibiting great diversity because of the unique size, conformation, and steric effect of molecular dopants. However, it is controversial how steric effects can limit the doping efficiency and to what extent dopants can be accommodated in polymers. Here, we employ two distinct conjugated polymers with different alkyl side-chain densities, where polymers are doped via anion-change, allowing greater variation in the incorporation of molecular dopants having different electrostatic potentials and shapes. We characterize the doping efficiency with regard to steric effects, considering the unique void space in the conjugated polymers. Our study reveals that doping efficiency of polymers with sparse alkyl side-chains is significantly greater than that with dense side-chains. A closest-packed supramolecule is realized with a particular combination of a sparse polymer and a large dopant, giving rise to high conductivity, air stability, and remarkably high work function. This work provides a critical insight into overcoming steric effects in molecular doping.

n-Alkylresorcinol Occurrence in Mercurialis perennis L. (Euphorbiaceae)

2010 ◽  
Vol 65 (3-4) ◽  
pp. 174-179 ◽  
Author(s):  
Peter Lorenz ◽  
Matthias Knödler ◽  
Julia Bertrams ◽  
Melanie Berger ◽  
Ulrich Meyer ◽  
...  
Keyword(s):  
Side Chain ◽  
Side Chains ◽  
Alkyl Side Chain ◽  
Alkyl Side Chains ◽  
Chain Lengths ◽  
New View

Investigation of the dichloromethane extracts from herbal and root parts of Mercurialis perennis L. afforded a mixture of 11 homologous n-alkylresorcinols (ARs) with saturated odd-numbered alkyl side chains (C15:0-C27:0). In addition to three predominant ARs (C19:0, C21:0 and C23:0), a number of minor ARs were identified by use of LC-MS/MS and GC-MS techniques. Among the compounds detected, four uncommon ARs with evennumbered alkyl side chain lengths were also determined. The overall AR concentration in herbal parts was 7 to 9 times higher compared to that of the roots. The results presented may open a new view on the phytochemistry and pharmacognosy of M. perennis and other members of the Euphorbiaceae family.

Low band gap conjugated polymers combining siloxane-terminated side chains and alkyl side chains: side-chain engineering achieving a large active layer processing window for PCE > 10% in polymer solar cells

2017 ◽  
Vol 5 (33) ◽  
pp. 17619-17631 ◽  
Author(s):  
Xuncheng Liu ◽  
Li Nian ◽  
Ke Gao ◽  
Lianjie Zhang ◽  
Lechi Qing ◽  
...  
Keyword(s):  
Conjugated Polymers ◽  
Active Layer ◽  
Polymer Solar Cells ◽  
Hole Transport ◽  
Random Copolymers ◽  
Side Chain ◽  
Active Layer Thickness ◽  
Side Chains ◽  
Alkyl Side Chains ◽  
Thickness Tolerance

Side-chain random copolymers show high 3-D hole transport and offer excellent active layer thickness tolerance.

Impact of the alkyl side chain position on the photovoltaic properties of solution-processable organic molecule donor materials

2016 ◽  
Vol 4 (30) ◽  
pp. 11747-11753 ◽  
Author(s):  
J. Zhang ◽  
X. W. Zhu ◽  
C. He ◽  
H. J. Bin ◽  
L. W. Xue ◽  
...  
Keyword(s):  
Organic Molecule ◽  
Side Chain ◽  
Side Chains ◽  
Alkyl Side Chain ◽  
Photovoltaic Properties ◽  
Alkyl Side Chains ◽  
Solution Processable ◽  
New Compounds

Two new compounds with alkyl side chains at different positions have a similar structure, but exhibit different photovoltaic properties.

scholarly journals Integrated multi-omics investigations reveal the key role of synergistic microbial networks in removing plasticizer di-(2-ethylhexyl) phthalate from estuarine sediments

2021 ◽  
Author(s):  
Sean Ting-Shyang Wei ◽  
Yi-Lung Chen ◽  
Yu-Wei Wu ◽  
Tien-Yu Wu ◽  
Yi-Li Lai ◽  
...  
Keyword(s):  
Phthalic Acid ◽  
Profile Analysis ◽  
Metabolite Profile ◽  
Degradation Pathway ◽  
Estuarine Sediments ◽  
Side Chain ◽  
Side Chains ◽  
Human Beings ◽  
Alkyl Side Chains ◽  
Ethylhexyl Phthalate

Di-(2-ethylhexyl) phthalate (DEHP) is the most widely used plasticizer worldwide with an annual global production of over eight million tons. Because of its improper disposal, endocrine-disrupting DEHP often accumulates in estuarine sediments in industrialized countries at sub-millimolar levels, resulting in adverse effects on both ecosystems and human beings. The microbial degraders and biodegradation pathways of DEHP in O2-limited estuarine sediments remain elusive. Here, we employed an integrated meta-omics approach to identify the DEHP degradation pathway and major degraders in this ecosystem. Estuarine sediments were treated with DEHP or its derived metabolites, o-phthalic acid and benzoic acid. The rate of DEHP degradation in denitrifying mesocosms was two times slower than that of o-phthalic acid, suggesting that side-chain hydrolysis of DEHP is the rate-limiting step of anaerobic DEHP degradation. On the basis of microbial community structures, functional gene expression, and metabolite profile analysis, we proposed that DEHP biodegradation in estuarine sediments is mainly achieved through synergistic networks between denitrifying proteobacteria. Acidovorax and Sedimenticola are the major degraders of DEHP side-chains; the resulting o-phthalic acid is mainly degraded by Aestuariibacter through the UbiD-dependent benzoyl-CoA pathway. We isolated and characterized Acidovorax sp. strain 210-6 and its extracellular hydrolase, which hydrolyzes both alkyl side-chains of DEHP. Interestingly, genes encoding DEHP/MEHP hydrolase and phthaloyl-CoA decarboxylase—key enzymes for side-chain hydrolysis and o-phthalic acid degradation, respectively—are flanked by transposases in these proteobacterial genomes, indicating that DEHP degradation capacity is likely transferred horizontally in microbial communities.

scholarly journals Unexpected Trends in the Hydrophobicity of Fluorinated Amino Acids Reflect Competing Changes in Polarity and Conformation

2018 ◽  
Author(s):  
João R. Robalo ◽  
Ana Vila Verde
Keyword(s):  
Amino Acids ◽  
Free Energy ◽  
Side Chain ◽  
Side Chains ◽  
Hydration Free Energy ◽  
Crossover Point ◽  
Fluorinated Amino Acids ◽  
Road Map ◽  
Alkyl Side Chains ◽  
The Impact

<div><div><div><p>Fluorination can dramatically improve the thermal and proteolytic stability of proteins and their enzymatic activity. Key to the impact of fluorination on protein properties is the hydrophobicity of fluorinated amino acids. We use molecular dynamics simulations, together with a new fixed-charge, atomistic force field, to quantify the changes in hydration free energy for amino acids with alkyl side chains and with 1 to 6 –CH to –CF side chain substitutions. Fluorination changes the hydration free energy by 1.5 to +2 kcal mol<sup>-</sup>1, but the number of fluorines is a poor predictor of hydrophobicity. Changes in hydration free energy reflect two main contributions: i) fluorination alters side chain-water interactions; we identify a crossover point from hydrophilic to hydrophobic fluoromethyl groups which may be used to estimate the hydrophobicity of fluorinated alkyl side-chains; ii) fluorination alters the number of backbone-water hydrogen bonds via changes in the relative side chain-backbone conformation. Our results offer a road map to mechanistically understand how fluorination alters hydrophobicity of (bio)polymers.</p></div></div></div>

A New Challenge of Polymer Thermoelectric Materials as Ecomaterials

2007 ◽  
Vol 539-543 ◽  
pp. 2329-2332 ◽  
Author(s):  
Yoshikazu Shinohara ◽  
Yoshio Imai ◽  
Yukihiro Isoda ◽  
Kentaro Hiraishi ◽  
Hachiro Nakanishi
Keyword(s):  
Electrical Conductivity ◽  
Seebeck Coefficient ◽  
Thermoelectric Properties ◽  
Oxidative Polymerization ◽  
Side Chain ◽  
Side Chains ◽  
Nmr Analysis ◽  
Alkyl Side Chains ◽  
High Seebeck Coefficient ◽  
Polymer Thermoelectric

Typical conductive polymers of poly(3-alkylthiophenes) were synthesized by oxidative polymerization. Polythiophene with no side chain was also electrolyticaly polymerized. Alkyl side chains were CnH2n+1 with n=4, 6, 8, 12. The regioregularity with the HT linkage was larger than 99% based on NMR analysis. We have evaluated the effect of side chain size on the thermoelectric properties of Seebeck coefficient and electrical conductivity. The results were as follows: 1) Seebeck coefficient decreased with an increasing electrical conductivity. 2) High Seebeck coefficient >1mV/K was observed at low electrical conductivity <10-2S/cm. 3) Small side chains, especially no side chain caused higher thermoelectric properties of polythiophene series.

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