A Possible Mechanism for the Extra-terrestrial Synthesis of Straight-chain Hydrocarbon

Nature ◽  
1964 ◽  
Vol 204 (4954) ◽  
pp. 181-182 ◽  
Author(s):  
C. B. JOHNSON ◽  
A. T. WILSON
Keyword(s):  
Straight Chain ◽  
Straight Chain Hydrocarbon ◽  
Chain Hydrocarbon

A new straight-chain hydrocarbon biomarker associated with anaerobic methane cycling

2001 ◽  
Vol 32 (8) ◽  
pp. 1019-1023 ◽  
Author(s):  
Volker Thiel ◽  
Jörn Peckmann ◽  
Oliver Schmale ◽  
Joachim Reitner ◽  
Walter Michaelis
Keyword(s):  
Straight Chain ◽  
Methane Cycling ◽  
Straight Chain Hydrocarbon ◽  
Chain Hydrocarbon

Examining the Decomposition of Ethylene-Vinyl Acetate Copolymers Using TG/GC/IR

1994 ◽  
Vol 48 (12) ◽  
pp. 1472-1476 ◽  
Author(s):  
Brian J. McGrattan
Keyword(s):  
Vinyl Acetate ◽  
Ethylene Vinyl Acetate ◽  
Straight Chain ◽  
Thermally Induced ◽  
Trapped Gases ◽  
Straight Chain Hydrocarbon ◽  
Complex Polymer ◽  
Made In ◽  
Eva Copolymers

With a combination of information from TG/IR and GC/IR measurements of the trapped gases, characterization of complex polymer decompositions can be made. In this paper, the thermally induced breakdown of ethylene-vinyl acetate (EVA) copolymers was studied. Results show that EVA undergoes a two-step decomposition: an acetate pyrolysis of the copolymer leaving a polyunsaturated linear hydrocarbon, followed by the breakdown of the hydrocarbon backbone to produce a large number of straight-chain hydrocarbon products.

scholarly journals The Microstructure and Rheology of  Complex Fluids Containing Na-caseinate

2021 ◽  
Author(s):  
◽  
Hui Lin Tan
Keyword(s):  
Emulsion Stability ◽  
Continuous Phase ◽  
Phase Behaviour ◽  
Particle Sizing ◽  
Straight Chain ◽  
Immiscible Liquids ◽  
Microstructure Stability ◽  
Fundamental Understanding ◽  
Emulsion Systems ◽  
Straight Chain Hydrocarbon

<p>Emulsions are widely utilised in commercial environments, such as in the food and cosmetic industries. In their simplest form, emulsions are a system consisting of two immiscible liquids in the presence of emulsifiers. To form an emulsion, an input of energy is required. In this thesis, Na-caseinate was used as the emulsifier and three systems were studied: soybean oil/Na-caseinate/water, palm oil/Na-caseinate/water and tetradecane/Nacaseinate/ water. Four main techniques were used to characterise the stabilised emulsions: laser diffraction particle sizing, PGSTE-NMR, rheology and cryo-SEM. Emulsion systems are extremely complex making control and predictability over their phase behaviour practically difficult. This is because the required overall characteristics of these colloids are strongly dependent on both the energy of formulation and the choice of an appropriate combination of emulsifier, dispersed phase and continuous phase. A full understanding of the microstructure, stability and physicochemical properties of caseinatestabilised emulsions has as yet not been achieved. For example, how does caseinate selfassembly control emulsion stability? How do concentrated caseinate-based emulsions differ from dilute ones and how do the different oils (food grade oils vs. straight chain hydrocarbon) affect the formation of emulsions? The aim of this PhD programme was to obtain data to allow a better fundamental understanding of the underlying parameters defining emulsion behaviour to be obtained ...</p>

scholarly journals The Microstructure and Rheology of  Complex Fluids Containing Na-caseinate

2021 ◽  
Author(s):  
◽  
Hui Lin Tan
Keyword(s):  
Emulsion Stability ◽  
Continuous Phase ◽  
Phase Behaviour ◽  
Particle Sizing ◽  
Straight Chain ◽  
Immiscible Liquids ◽  
Microstructure Stability ◽  
Fundamental Understanding ◽  
Emulsion Systems ◽  
Straight Chain Hydrocarbon

<p>Emulsions are widely utilised in commercial environments, such as in the food and cosmetic industries. In their simplest form, emulsions are a system consisting of two immiscible liquids in the presence of emulsifiers. To form an emulsion, an input of energy is required. In this thesis, Na-caseinate was used as the emulsifier and three systems were studied: soybean oil/Na-caseinate/water, palm oil/Na-caseinate/water and tetradecane/Nacaseinate/ water. Four main techniques were used to characterise the stabilised emulsions: laser diffraction particle sizing, PGSTE-NMR, rheology and cryo-SEM. Emulsion systems are extremely complex making control and predictability over their phase behaviour practically difficult. This is because the required overall characteristics of these colloids are strongly dependent on both the energy of formulation and the choice of an appropriate combination of emulsifier, dispersed phase and continuous phase. A full understanding of the microstructure, stability and physicochemical properties of caseinatestabilised emulsions has as yet not been achieved. For example, how does caseinate selfassembly control emulsion stability? How do concentrated caseinate-based emulsions differ from dilute ones and how do the different oils (food grade oils vs. straight chain hydrocarbon) affect the formation of emulsions? The aim of this PhD programme was to obtain data to allow a better fundamental understanding of the underlying parameters defining emulsion behaviour to be obtained ...</p>

scholarly journals Lipidomics of facial sebum in the comparison between acne and non-acne adolescents with dark skin

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Obumneme Emeka Okoro ◽  
Adebomi Adenle ◽  
Matteo Ludovici ◽  
Mauro Truglio ◽  
Federico Marini ◽  
...  
Keyword(s):  
Relative Abundance ◽  
Building Blocks ◽  
Carbon Chain ◽  
Gas Chromatography Mass Spectrometry ◽  
Lower Percentage ◽  
Void Space ◽  
Straight Chain ◽  
Dark Skin ◽  
Cross Sectional ◽  
Weight Percentage

AbstractLipidomics is advantageous in the study of sebum perturbations occurring in acne. An extended evaluation of the sebum lipid profiles in acne-prone sebaceous areas is lacking in dark skin. Yet, there is a void space in understanding how the building blocks of sebum lipids, i.e. individual fatty acids (FAs), are intertwined with acne-prone skin. We aimed to determine the sebum lipidome in facial areas of adolescents with and without acne in Nigeria. A cross-sectional analytical study was conducted in 60 adolescents/young adults divided in 30 acne patients (15F, 15M) and 30 age and sex-matched controls. Sebum samples obtained from foreheads and cheeks were analysed separately by gas chromatography–mass spectrometry (GCMS) and thin layer chromatography (HPTLC). Distributions of sebum components were investigated with multivariate ANOVA-simultaneous component analysis (ASCA). Sebum incretion in acne was paralleled by significantly higher abundance of triglycerides, wax esters, and squalene together with monounsaturated FAs (MUFAs), and straight chain saturated FAs (SFAs), especially those with odd-carbon chain, i.e. C13:0, C15:0, and C17:0. Profiling weight/weight percentage of individual components revealed that, in acne, the free FAs (FFAs) array was shifted towards higher relative abundance of the SFAs C15:0, C16:0, and C17:0 and lower percentage of the anteiso-branched FFAs with 12, 14, 16, and 18 carbons. In acne patients, MUFAs and PUFAs were quantitatively increased and decreased on foreheads and cheeks, respectively. Relative abundance of fatty alcohols was decreased in acne independent on the site. The results indicated that acne associates with site-specific derangement of the pathways regulating the balance among odd straight-chain and branched-chain SFAs, MUFAs, which included sapienate (C16:1n-10), PUFAs, and squalene.

TetR-family transcriptional repressor Thermus thermophilus FadR controls fatty acid degradation

Microbiology ◽  
2011 ◽  
Vol 157 (6) ◽  
pp. 1589-1601 ◽  
Author(s):  
Yoshihiro Agari ◽  
Kazuko Agari ◽  
Keiko Sakamoto ◽  
Seiki Kuramitsu ◽  
Akeo Shinkai
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Target Genes ◽  
Thermus Thermophilus ◽  
Acyl Chain ◽  
Metabolic Energy ◽  
Straight Chain ◽  
Fatty Acid Degradation ◽  
Acid Degradation

In the extremely thermophilic bacterium Thermus thermophilus HB8, one of the four TetR-family transcriptional regulators, which we named T. thermophilus FadR, negatively regulated the expression of several genes, including those involved in fatty acid degradation, both in vivo and in vitro. T. thermophilus FadR repressed the expression of the target genes by binding pseudopalindromic sequences covering the predicted −10 hexamers of their promoters, and medium-to-long straight-chain (C10–18) fatty acyl-CoA molecules were effective for transcriptional derepression. An X-ray crystal structure analysis revealed that T. thermophilus FadR bound one lauroyl (C12)-CoA molecule per FadR monomer, with its acyl chain moiety in the centre of the FadR molecule, enclosed within a tunnel-like substrate-binding pocket surrounded by hydrophobic residues, and the CoA moiety interacting with basic residues on the protein surface. The growth of T. thermophilus HB8, with palmitic acid as the sole carbon source, increased the expression of FadR-regulated genes. These results indicate that in T. thermophilus HB8, medium-to-long straight-chain fatty acids can be used for metabolic energy under the control of FadR, although the major fatty acids found in this strain are iso- and anteiso-branched-chain (C15 and 17) fatty acids.

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