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1. Chemical structure of medium-scale liquid pool fires

Author:
Ryan Falkenstein-Smith; Kunhyuk Sung; Jian Chen; Anthony Hamins
Source:
Fire safety journal 2021 v.120 pp. 103099
ISSN:
0379-7112
Subject:
chemical structure,   etc   ; acetone; burning; ethanol; fires; fuels; gas chromatography-mass spectrometry; liquids; methanol; soot; spectrometers;     Show all 11 Subjects
Abstract:
... This work documents a series of time-averaged local gas species measurements made throughout the centerline profile of 30 cm methanol, ethanol, and acetone pool fires steadily burning in a quiescent environment. All gas species measurements were obtained using extractive sampling, then analyzed using a gas chromatograph equipped with a mass spectrometer detector (GC/MS). The volume fraction of eac ...
DOI:
10.1016/j.firesaf.2020.103099

2. Mapping Chemical Structure–Glass Transition Temperature Relationship through Artificial Intelligence

Author:
Luis A. Miccio; Gustavo A. Schwartz
Source:
Macromolecules 2021 v.54 no.4 pp. 1811-1817
ISSN:
1520-5835
Subject:
chemical structure,   etc   ; acrylates; artificial intelligence; glass transition temperature; principal component analysis;     Show all 5 Subjects
Abstract:
... Artificial neural networks (ANNs) have been successfully used in the past to predict different properties of polymers based on their chemical structure and to localize and quantify the intramonomer contributions to these properties. In this work, we propose to move forward in order to use the mathematical framework of the ANN for embedding the chemical structure of monomers into a high ...
DOI:
10.1021/acs.macromol.0c02594

3. The “fine chemical” structure of medullosalean cuticles and infrared spectroscopy

Author:
Erwin L. Zodrow
Source:
Review of palaeobotany and palynology 2021 v.287 pp. 104383
ISSN:
0034-6667
Subject:
chemical structure,   etc   ; carbon; fossils; infrared spectroscopy; magnetism; mass spectrometry; medicine; models; paleobotany; palynology; pyrolysis gas chromatography; Canada;     Show all 12 Subjects
Abstract:
... were supported by carbon 13 magnetic resonance, or pyrolysis-gas chromatography coupled with mass spectrometry. This paper outlines and summarizes these early efforts, focusing, however, on the research opportunity that exists to unravel the fine chemical structure of the fossil cuticle. This may be the “last frontier” in the chemical study of plant-fossil cuticles. Success hinges, however ...
DOI:
10.1016/j.revpalbo.2021.104383

4. Insight into intramolecular chemical structure modifications by on-surface reaction using photoemission tomography

Author:
Iulia Cojocariu; Florian Feyersinger; Peter Puschnig; Luca Schio; Luca Floreano; Vitaliy Feyer; Claus M. Schneider
Source:
Chemical communications 2021 v.57 no.24 pp. 3050-3053
ISSN:
1364-548X
Subject:
chemical structure,   etc   ; dehydrogenation; energy; ligands; oxidation; tomography;     Show all 6 Subjects
Abstract:
... The sensitivity of photoemission tomography (PT) to directly probe single molecule on-surface intramolecular reactions will be shown here. PT application in the study of molecules possessing peripheral ligands and structural flexibility is tested on the temperature-induced dehydrogenation intramolecular reaction on Ag(100), leading from CoOEP to the final product CoTBP. Along with the ring-closure ...
DOI:
10.1039/d1cc00311a

5. Effect of temperature on Shenfu coal pyrolysis process related to its chemical structure transformation

Author:
Kai Xu; Song Hu; Liangping Zhang; Hanjian Li; Yifeng Chen; Zhe Xiong; Jun Xu; Long Jiang; Yi Wang; Sheng Su; Jun Xiang
Source:
Fuel processing technology 2021 v.213 pp. 106662
ISSN:
0378-3820
Subject:
chemical structure,   etc   ; carbon; carbonation; coal; condensation reactions; evolution; industry; pyrolysis; temperature;     Show all 9 Subjects
Abstract:
... of oxygen−/nitrogen-containing heteroatom compounds in heavy tar were significantly reduced with the increase of temperature. Finally, the devolatilization mechanism responsible for the evolution of chemical structure of Shenfu coal pyrolyzed at elevated temperatures was proposed. ...
DOI:
10.1016/j.fuproc.2020.106662

6. Effect of intense pulsed light on Lactobacillus bulgaricus exopolysaccharide yield, chemical structure and antioxidant activity

Author:
Xinyu Ge; Fengming Ma; Baiqing Zhang
Source:
International journal of food science & technology 2021 v.56 no.2 pp. 865-873
ISSN:
0950-5423
Subject:
chemical structure,   etc   ; Fourier transform infrared spectroscopy; Lactobacillus delbrueckii subsp. bulgaricus; X-ray diffraction; antioxidant activity; environmental protection; exopolysaccharides; food science; nuclear magnetic resonance spectroscopy; pulsed light irradiation;     Show all 10 Subjects
Abstract:
... chemical structure and surface morphology. The antioxidant activity of EPS was evaluated by DPPH, Fe²⁺ chelating and reducing power assays. The findings demonstrate that IPL could be a novel environment protection method for improving the production of EPS. The research results provide a theoretical basis for whether IPL is a new type of environmental protection method and can be used to improve EPS ...
DOI:
10.1111/ijfs.14730

7. Biomass-based flexible nanoscale carbon fibers: effects of chemical structure on energy storage properties

Author:
Hao Zheng; Qiping Cao; Mengni Zhu; Dang Xu; Haoyu Guo; Yao Li; Jinghui Zhou
Source:
Journal of materials chemistry A 2021 v.9 no.16 pp. 10120-10134
ISSN:
2050-7496
Subject:
chemical structure,   etc   ; biomass; capacitance; carbon; cellulose acetate; electrochemical capacitors; energy; energy density; fractionation; lignin; molecular weight; petroleum; surface area;     Show all 13 Subjects
Abstract:
... The preparation of flexible nano-scale carbon materials with good energy storage properties using biomass is a challenging task. Herein, we developed a simple and efficient strategy for preparing high-performance green nano-scale carbon fibrous materials (CFs). A fractionated process is performed to obtain lignin with different chemical structures, including active chemical groups, branched ...
DOI:
10.1039/d1ta00317h

8. Chemical structure and anti-inflammatory activity of a branched polysaccharide isolated from Phellinus baumii

Author:
Yuqing Sun; Jinxi Huo; Shi Zhong; Jianxun Zhu; Yougui Li; Xiaojun Li
Source:
Carbohydrate polymers 2021 v.268 pp. 118214
ISSN:
0144-8617
Subject:
chemical structure,   etc   ; Phellinus; anti-inflammatory activity; arabinose; galactose; gastroenteritis; glucose; interleukin-10; macrophages; mannose; phosphorylation; polysaccharides; ulcerative colitis;     Show all 13 Subjects
Abstract:
... Phellinus baumii is used to treat inflammatory bowel disease (IBD) and gastroenteritis. In this study, a 46 kDa heteropolysaccharide SHPS-1 was isolated from fruiting bodies of P. baumii. SHPS-1 consisted of arabinose, mannose, glucose, and galactose at a molar ratio of 2.2:15.7:49.3:32.8. SHPS-1 had a backbone containing 1,3-linked β-D-Glcp and 1,6-linked α-D-Galp residues, and Araf, Manp and Gal ...
DOI:
10.1016/j.carbpol.2021.118214

9. Uptake and translocation of organophosphate esters by plants: Impacts of chemical structure, plant cultivar and copper

Author:
Beibei Hu; Longfei Jiang; Qian Zheng; Chunling Luo; Dayi Zhang; Shaorui Wang; Yucheng Xie; Gan Zhang
Source:
Environment international 2021 v.155 pp. 106591
ISSN:
0160-4120
Subject:
chemical structure,   etc   ; bioaccumulation; carrots; copper; corn; cultivars; environment; environmental assessment; food chain; hydrophobicity; organophosphorus compounds; sorption;     Show all 12 Subjects
Abstract:
... Organophosphate esters (OPEs) are normally used as flame retardants, plasticizers and lubricants, but have become environmental pollutants. Because OPEs are normally present alongside heavy metals in soils, the effects of interactions between OPEs and heavy metals on plant uptake of OPEs need to be determined. In this study, we investigated the effects of OPEs chemical structure, plant cultivar ...
DOI:
10.1016/j.envint.2021.106591

10. Effect of chemical structure on optical properties of secondary organic aerosols derived from C12 alkanes

Author:
Junling Li; Weigang Wang; Kun Li; Wenyu Zhang; Chao Peng; Mingyuan Liu; Yan Chen; Li Zhou; Hong Li; Maofa Ge
Source:
Science of the total environment 2021 v.751 pp. 141620
ISSN:
0048-9697
Subject:
chemical structure,   etc   ; absorption; aerosols; air pollution; alkanes; chemical composition; electrospray ionization mass spectrometry; environment; oligomerization; refractive index; spectrometers; temperature;     Show all 12 Subjects
Abstract:
... With the development of the economy, anthropogenic emissions in the atmospheric environment increases, and air pollution has caused wide public concern. Vehicle exhaust is an important emission source in the atmosphere, and alkanes are the representative components in it. In this study, the optical properties of secondary organic aerosol (SOA) derived from several C₁₂ alkanes (2-methylundecane, he ...
DOI:
10.1016/j.scitotenv.2020.141620

11. Multiscale analysis of the thermal degradation of polyamide 6,6: Correlating chemical structure to mechanical properties

Author:
M. Pliquet; M. Rapeaux; F. Delange; P.O. Bussiere; S. Therias; J.L. Gardette
Source:
Polymer degradation and stability 2021 v.185 pp. 109496
ISSN:
0141-3910
Subject:
crystal structure; hardness; microstructure; models; molecular weight; oxidation; polyamides; thermal degradation
Abstract:
... In this paper, the thermal oxidation of polyamide 6,6 between 140°C and 200°C is evaluated. The aim of this study is to correlate the modifications of the polymer properties on scales ranging from molecular to macroscopic. Chemical structure changes are monitored by infrared and UV-visible spectroscopies. The modifications of the microstructure are evaluated using DSC while molar mass evolution ...
DOI:
10.1016/j.polymdegradstab.2021.109496

12. Melting point prediction of organic molecules by deciphering the chemical structure into a natural language

Author:
Weiming Mi; Huijun Chen; Donghua (Alan) Zhu; Tao Zhang; Feng Qian
Source:
Chemical communications 2021 v.57 no.21 pp. 2633-2636
ISSN:
1364-548X
Subject:
drugs; models; prediction
Abstract:
... not decrease with increasing size, complexity, and structural flexibility of molecules. By representing the chemical structure as a natural language, this NLP-based model offers a potential tool for quantitative structure–property prediction for drug discovery and development. ...
DOI:
10.1039/d0cc07384a

13. Translation of Chemical Structure into Dissipative Particle Dynamics Parameters for Simulation of Surfactant Self-Assembly

Author:
Ennio Lavagnini; Joanne L. Cook; Patrick B. Warren; Christopher A. Hunter
Source:
Journal of physical chemistry 2021 v.125 no.15 pp. 3942-3952
ISSN:
1520-5207
Subject:
algorithms; density functional theory; mechanics; micelles; molecular dynamics; sugars; surfactants
Abstract:
... Dissipative particle dynamics (DPD) can be used to simulate the self-assembly properties of surfactants in aqueous solutions, but in order to simulate a new compound, a large number of new parameters are required. New methods for the calculation of reliable DPD parameters directly from chemical structure are described, allowing the DPD approach to be applied to a much wider range of organic ...
DOI:
10.1021/acs.jpcb.1c00480

14. Temporal and spatial evolution of biochar chemical structure during biomass pellet pyrolysis from the insights of micro-Raman spectroscopy

Author:
Yuanjing Chen; Syed Shatir A. Syed-Hassan; Zhe Xiong; Qiaoling Li; Xun Hu; Jun Xu; Qiangqiang Ren; Zengtong Deng; Xuepeng Wang; Sheng Su; Song Hu; Yi Wang; Jun Xiang
Source:
Fuel processing technology 2021 v.218 pp. 106839
ISSN:
0378-3820
Subject:
chemical structure,   etc   ; Raman spectroscopy; aromatic compounds; biochar; biomass; carbon; heat transfer; mass transfer; pyrolysis; sawdust; temperature;     Show all 11 Subjects
Abstract:
... Biomass pellet is a popular fuel, and pyrolytic char can be a promised carbon material, further understanding char structural evolution can promote its utilization. To deeply investigate the evolution of char chemical structure and its heterogeneity during biomass pellet pyrolysis process, a new method was developed to fragment the char in space, and the chemical structures of the fragmented ...
DOI:
10.1016/j.fuproc.2021.106839

15. Study on pore and chemical structure characteristics of atmospheric circulating fluidized bed coal gasification fly ash

Author:
Jiawei Li; Zhichao Chen; Liankai Li; Yanyu Qiao; Zhenhua Yuan; Lingyan Zeng; Zhengqi Li
Source:
Journal of cleaner production 2021 v.308 pp. 127395
ISSN:
0959-6526
Subject:
atmospheric pressure; cakes; circular economy; coal; coal gasification; combustion; fluidized beds; fly ash; fractal dimensions; graphene
Abstract:
... The pore and chemical structure characteristics of the raw coal and the coal gasification fly ash (CGFA) in an atmospheric pressure circulating fluidized bed gasifier with a gas production capacity of 20000 and 40000 Nm³ h⁻¹ were studied. The results indicated the presence of developed pore structure and high carbon content of the CGFA. The comprehensive fractal dimension method was proposed ...
DOI:
10.1016/j.jclepro.2021.127395

16. Short communication: Chemical structure, concentration, and pH are key factors influencing antimicrobial activity of conjugated bile acids against lactobacilli

Author:
Xue-Jiao Wang; Bing-Yan Chen; Bao-Wei Yang; Tian-Li Yue; Chun-Feng Guo
Source:
Journal of dairy science 2021 v.104 no.2 pp. 1524-1530
ISSN:
0022-0302
Subject:
chemical structure,   etc   ; Lactobacillus; antimicrobial properties; bile; bile resistance; dairy science; glycocholic acid; humans; pH; probiotics; taurocholic acid;     Show all 11 Subjects
Abstract:
... Effects of chemical structure, concentration, and pH on antimicrobial activity of conjugated bile acids were investigated in 4 strains of lactobacilli. Considerable differences were observed in the antimicrobial activity between the 6 human conjugated bile acids, including glycocholic acid, taurocholic acid, glycodeoxycholic acid, taurodeoxycholic acid, glycochenodeoxycholic acid ...
DOI:
10.3168/jds.2020-19293

17. Chitin nanocrystals as Pickering stabilizer for O/W emulsions: Effect of the oil chemical structure on the emulsion properties

Author:
Fatma Ben Cheikh; Ayman Ben Mabrouk; Albert Magnin; Jean-Luc Putaux; Sami Boufi
Source:
Colloids and surfaces 2021 v.200 pp. 111604
ISSN:
0927-7765
Subject:
chemical structure,   etc   ; acid hydrolysis; chitin; droplet size; emulsifying; emulsions; hydrochloric acid; nanocrystals; rheology; soybean oil; stabilizers;     Show all 11 Subjects
Abstract:
... Chitin nanocrystals (ChNCs) produced by hydrochloric acid hydrolysis of chitin were used as stabilizing agent for oil-in-water (O/W) emulsification of soybean oil (SO), acrylated soybean oil (ASO), and epoxidized soybean oil (ESO). The emulsion stability, droplet size, and rheology of the emulsion were found to be significantly affected by the oil chemical structure. Strong interaction between ...
DOI:
10.1016/j.colsurfb.2021.111604

18. Cyclic and acyclic alcohols: a structure-activity relationship study correlation between insecticidal activity and chemical structure

Author:
Amel Ben Hamouda; Enis Ben Bnina; Ikbal Chaieb; Asma Laarif; Hichem Ben Jannet
Source:
International journal of tropical insect science 2021 v.41 no.2 pp. 961-968
ISSN:
1742-7592
Subject:
Tribolium castaneum; air; bioassays; citronellol; essential oils; eugenol; fumigants; insecticidal properties; insects; lethal dose 50; mortality; stored grain; structure-activity relationships
Abstract:
... The efficiency of essential oil depends upon the chemical nature, composition, and the relative proportion of its functional groups. In some case, individual compounds can exhibit a pertinent effect than do the essential oils. To underline their efficiency according to their chemical structure, five cyclic and acyclic alcohols were tested in vitro for their potential insecticidal and repellent ...
DOI:
10.1007/s42690-020-00277-7

19. Effect of crosslinking processing on the chemical structure and biocompatibility of a chitosan-based hydrogel

Author:
Jingwen Yang; Gangqiang Liang; Tuo Xiang; Wenbei Situ
Source:
Food chemistry 2021 v.354 pp. 129476
ISSN:
0308-8146
Subject:
bioavailability; biocompatibility; cell viability; chitosan; colon; crosslinking; digestive tract; electrostatic interactions; food chemistry; hydrogels; hydrophilicity; sodium; sodium tripolyphosphate
Abstract:
... Chitosan (CS)-based hydrogels with different structures were prepared to ensure the bioavailability of bioactive components. With the electrostatic interaction between CS and anionic crosslinkers, the structure of the CS-based hydrogel changed and influenced the swelling ability, which was beneficial for maintaining bioactive ingredients in the hydrogel. Compared with sodium hexametaphosphate, hyd ...
DOI:
10.1016/j.foodchem.2021.129476

20. Lignin dissolution model in formic acid–acetic acid–water systems based on lignin chemical structure

Author:
Qingzhi Ma; Lizhen Wang; Huamin Zhai; Hao Ren
Source:
International journal of biological macromolecules 2021 v.182 pp. 51-58
ISSN:
0141-8130
Subject:
Eucalyptus; bamboos; cohesion; hydrogen; lignin; models; quantitative analysis; softwood; solubility; solvents; spectroscopy; wheat straw; woody biomass
Abstract:
... The separation of lignin from woody biomass and subsequent conversion into useful products requires a solution to the problem of its solubility. The expanded C₉ formula of lignin, along with its atomic and functional groups, was determined by elemental analysis and NMRs spectroscopy. Based on the thus-obtained expanded C₉ formula, the cohesion parameters of lignin dispersion (10.8–11.1 cal¹/²·cm⁻³ ...
DOI:
10.1016/j.ijbiomac.2021.03.179