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1. Catalytic Enantioselective Dehydrogenative Si–O Coupling to Access Chiroptical Silicon-Stereogenic Siloxanes and Alkoxysilanes

Author:
Jiefeng Zhu; Shuyou Chen; Chuan He
Source:
Journal of the American Chemical Society 2021 v.143 no.14 pp. 5301-5307
ISSN:
1520-5126
Subject:
siloxanes,   etc   ; dehydrogenation; enantioselectivity; fluorescence;     Show all 4 Subjects
Abstract:
... A rhodium-catalyzed enantioselective construction of triorgano-substituted silicon-stereogenic siloxanes and alkoxysilanes is developed. This process undergoes a direct intermolecular dehydrogenative Si–O coupling between dihydrosilanes with silanols or alocohols, giving access to a variety of highly functionalized chiral siloxanes and alkoxysilanes in decent yields with excellent stereocontrol ...
DOI:
10.1021/jacs.1c01106

2. Paper-based filter membrane for high-efficient sampling and direct mass spectrometric analysis of siloxanes in outdoor air

Author:
Zhifeng Niu; Jun Shi; Zeru Xu; Yajun Zheng; Zhicheng Xiang; Jia Zhao; Zhiping Zhang
Source:
Atmospheric environment 2021 v.254 pp. 118427
ISSN:
1352-2310
Subject:
siloxanes,   etc   ; air; atmospheric pressure; climate; environment; environmental assessment; humidity; mass spectrometry; paper; silica; solvents; temperature; toxicity; wind direction; wind speed;     Show all 15 Subjects
Abstract:
... Siloxanes have been found widespread usages in our daily lives, but the knowledge on their migration, transformation and toxicity is still limited. Herein we explored the feasibility of using one-sided silica coated paper as filter membrane to capture siloxanes in the outdoor air, followed by direct mass spectrometric analysis. In contrast to mostly utilized fiber membrane, silica coated paper ...
DOI:
10.1016/j.atmosenv.2021.118427

3. Removal of siloxanes from biogas upgraded to biomethane by Cryogenic Temperature Condensation System

Author:
Grzegorz Piechota
Source:
Journal of cleaner production 2021 v.308 pp. 127404
ISSN:
0959-6526
Subject:
siloxanes,   etc   ; biogas; carbon dioxide; chlorine; flame ionization; fluorine; heat; landfills; life cycle assessment; relative humidity; silica; temperature; volatile organic compounds;     Show all 13 Subjects
Abstract:
... An eco-friendly system based on Cryogenic Temperature Condensation System (CTCS) that was designed to remove siloxanes as well as another organic and inorganic impurities from biogas was investigated. Moreover, the analyzed biogas was theoretically upgraded to biomethane and the CTCS was implemented as a part of biogas upgrading pre-treatment process. Testing was conducted during three stages ...
DOI:
10.1016/j.jclepro.2021.127404

4. Methyl siloxanes in road dust from a large silicone manufacturing site in China: implications of human exposure

Author:
Jiali Cheng; Zhenwu Tang; Yan Ma; Hongmin Yin; Tong Meng; Jiazheng Sun
Source:
Environmental science and pollution research 2021 v.28 no.13 pp. 16054-16064
ISSN:
0944-1344
Subject:
dust; exposure scenario; humans; pollution; research; silicone; surveys; China
Abstract:
... Methyl siloxanes are becoming increasingly prevalent in the environment because of their extensive use in various consumer products. Little is known about the distribution of these chemicals around factories or their presence in road dust. We conducted a survey of four cyclic (D₃–D₆) and 13 linear (L₄–L₁₆) siloxanes in road dusts around a manufacturing site and found a total siloxane ...
DOI:
10.1007/s11356-020-11773-1

5. Air pollution caused by phthalates and cyclic siloxanes in Hanoi, Vietnam: Levels, distribution characteristics, and implications for inhalation exposure

Author:
Hoang Quoc Anh; Ha My Nu Nguyen; Trung Quang Do; Khiem Quang Tran; Tu Binh Minh; Tri Manh Tran
Source:
Science of the total environment 2021 v.760 pp. 143380
ISSN:
0048-9697
Subject:
siloxanes,   etc   ; air; air pollution; environment; inhalation exposure; phthalates; phthalic acid; urban areas; Vietnam;     Show all 9 Subjects
Abstract:
... Contamination status and distribution characteristics of ten phthalic acid esters (PAEs) and three cyclic volatile methyl siloxanes (CSs) were determined in the air (gas and particle) samples collected from indoor and outdoor spaces of several chemistry laboratories, offices, and homes from urban area of Hanoi, the capital city of Vietnam. Air concentrations of Σ10PAEs (median 688; range 142–2390 ...
DOI:
10.1016/j.scitotenv.2020.143380

6. Suitability of Thermal Swing Adsorption for the Treatment of Siloxanes and Toluene in Biogas: An Experimental Study

Author:
Téo Polimann; Michel Ondarts; Jonathan Outin; Nolwenn Le Pierrès; Evelyne Gonze
Source:
Energy & fuels 2021 v.35 no.6 pp. 4954-4965
ISSN:
1520-5029
Subject:
siloxanes,   etc   ; activated carbon; adsorbents; adsorption; biogas; desorption; energy; temperature; toluene;     Show all 9 Subjects
Abstract:
... at high temperatures: no significant decrease was found between the 4th cycle and the 50th cycle. On the contrary, a constant decrease was measured at moderate temperatures. Both the surface analysis (infrared measure) and the analysis of the gas from the desorption step indicate that siloxanes were deposited on the ACC and polymerized to a high-molecular-weight polymer. This reaction could cause ACC ...
DOI:
10.1021/acs.energyfuels.0c03959

7. Development of a New Passive Sampling Method for the Measurement of Atmospheric Linear and Cyclic Volatile Methyl Siloxanes

Author:
Fulya Okan; Mustafa Odabasi; Baris Yaman; Yetkin Dumanoglu
Source:
Environmental science & technology 2021 v.55 no.8 pp. 4522-4531
ISSN:
1520-5851
Subject:
siloxanes,   etc   ; adsorbents; air; infrastructure; land use; solvents; wastewater treatment;     Show all 7 Subjects
Abstract:
... A new passive sampling method was developed and characterized to measure atmospheric volatile methyl siloxanes (VMS). The infrastructure of a commercial passive air sampler (PAS) was used along with XAD-2 resin as the adsorbent. Experimental sampling rates (SR) determined using collocated active and passive samplers ranged between 0.0363 (L5) and 0.0561 (D3) m³/day and agreed well ...
DOI:
10.1021/acs.est.1c00227

8. Synthesis, Characterization, and Thermal Properties of Fluoropyridyl-Functionalized Siloxanes of Diverse Polymeric Architectures

Author:
Kevin A. Stewart; Dylan Shuster; Maria Leising; Isaac Coolidge; Erica Lee; Charles Stevens; Andrew J. Peloquin; Daniel Kure; Abby R. Jennings; Scott T. Iacono
Source:
Macromolecules 2021 v.54 no.10 pp. 4871-4879
ISSN:
1520-5835
Subject:
Lewis bases; alkenes; crosslinking; glass transition; polydimethylsiloxane; polymerization; pyrolysis; thermal stability
Abstract:
... ) of PFP in good isolated yields. These multi-reactive monomers were polymerized via Pt-catalyzed hydrosilylation with hydride-terminated polydimethylsiloxanes (H-PDMSs) possessing varying degrees of polymerization and cross-linked with the highly functionalized octadimethylhydrosilyl cubic siloxane. These resulting polymers of varying architecture possessed exceptional thermal stability with no onset ...
DOI:
10.1021/acs.macromol.1c00333

9. Poly(dimethylsiloxane) and oligo(dimethylsiloxane) solvent effects on aromatic donor–acceptor interactions

Author:
Shogo Amemori; Kyoka Kikuchi; Motohiro Mizuno
Source:
Chemical communications 2021 v.57 no.9 pp. 1141-1144
ISSN:
1364-548X
Subject:
siloxanes,   etc   ; aromatic compounds; solubility; solvents;     Show all 4 Subjects
Abstract:
... Solvents with a wide range of polarities, including poly(dimethylsiloxane) and oligo(dimethylsiloxane), were used to evaluate aromatic donor–acceptor interactions between pyrene and pyromellitic diimide derivatives. The donor–acceptor interactions were stronger in siloxane solvents than in aliphatic solvents, possibly because of the poor solubility of the aromatics in siloxanes. ...
DOI:
10.1039/d0cc06638a

10. Siloxanes removal in a two-phase partitioning biotrickling filter: Influence of the EBRT and the organic phase

Author:
Celia Pascual; Sara Cantera; Raúl Muñoz; Raquel Lebrero
Source:
Renewable energy 2021 v.177 pp. 52-60
ISSN:
0960-1481
Subject:
bacterial communities; biofilters; biogas; combustion; oils; silicone; solubility
Abstract:
... Biogas contain minor concentration of volatile methyl siloxanes (VMS), responsible for severe damages in turbines or internal combustion engines. Sustainable biological processes for VMS abatement are limited by the low aqueous solubility of VMS. In order this limitation, the siloxanes (D4, D5, L2 and L3) removal performance of a two-phase partitioning biotrickling filter (TP-BTF) was study ...
DOI:
10.1016/j.renene.2021.05.144

11. Oligodimethylsiloxane-Oligoproline Block Co-Oligomers: the Interplay between Aggregation and Phase Segregation in Bulk and Solution

Author:
Brigitte A.G. Lamers; Andreas Herdlitschka; Tobias Schnitzer; Mathijs F.J. Mabesoone; Sandra M.C. Schoenmakers; Bas F.M. de Waal; Anja R.A. Palmans; Helma Wennemers; E.W. Meijer
Source:
Journal of the American Chemical Society 2021 v.143 no.10 pp. 4032-4042
ISSN:
1520-5126
Subject:
siloxanes,   etc   ; aggregation behavior; gels; proline; solvents;     Show all 5 Subjects
Abstract:
... siloxanes permits a study of the aggregation behavior of oligoproline moieties in a variety of solvents, including a highly apolar solvent like methylcyclohexane. The apolar solvent is more reminiscent of the polarity of the siloxane bulk, which gives insights into the supramolecular interactions that govern both bulk and solution assembly processes of the oligoproline. This extensive structural ...
DOI:
10.1021/jacs.1c01076

12. Are telechelic polysiloxanes better than hemi-telechelic for self-cleaning applications?

Author:
Muhammad Naveed; Muhammad Rabnawaz
Source:
Journal of colloid and interface science 2021 v.600 pp. 174-186
ISSN:
0021-9797
Subject:
siloxanes,   etc   ; methylmethacrylate; polymerization; separation;     Show all 4 Subjects
Abstract:
... Polysiloxanes are becoming new trend in self-cleaning (oil- and water‐repellent) applications due to their low-cost and environmentally friendly nature. Lower phase separation of polysiloxanes in coating matrix is critical to obtain excellent self-cleaning properties. We hypothesize that telechelic polysiloxanes can bind to coating matrix at both ends and thus will suppress phase separation of pol ...
DOI:
10.1016/j.jcis.2021.05.007

13. Sampling, on-line and off-line measurement of organic silicon compounds at an industrial biogas-fed 175-kWe SOFC plant

Author:
Adelaide Calbry-Muzyka; Mohamed Tarik; Marta Gandiglio; Jianrong Li; Debora Foppiano; Iris de Krom; Dita Heikens; Christian Ludwig; Serge Biollaz
Source:
Renewable energy 2021 v.177 pp. 61-71
ISSN:
0960-1481
Subject:
siloxanes,   etc   ; adsorption; biogas; energy industry; fuel cells; liquids; silicon;     Show all 7 Subjects
Abstract:
... The use of biogas in the energy sector requires efficient removal of harmful trace levels of impurities. Reliable and robust online analytical equipment to measure these impurities is necessary and must be validated using offline techniques. In this work, total silicon and siloxanes were measured at an industrial solid oxide fuel cell fed by biogas. SOFC anodes are sensitive to silicon-based ...
DOI:
10.1016/j.renene.2021.05.047

14. Maternal transfer and occurrence of siloxanes, chlorinated paraffins, metals, PFAS and legacy POPs in herring gulls (Larus argentatus) of different urban influence

Author:
Nina C. Knudtzon; Helene Thorstensen; Anders Ruus; Morten Helberg; Kine Bæk; Ellen K. Enge; Katrine Borgå
Source:
Environment international 2021 v.152 pp. 106478
ISSN:
0160-4120
Subject:
siloxanes,   etc   ; Larus argentatus; airports; blood; bromination; capital; carbon; eggs; environment; females; food waste; herring; lipophilicity; niches; nitrogen; persistent organic pollutants; polychlorinated biphenyls; urbanization; waste management; Norway;     Show all 20 Subjects
Abstract:
... volatile methyl siloxane (cVMSs), which to our knowledge have not been assessed in herring gulls previously. We compare concentrations of legacy and emerging contaminants and metals in blood and eggs between two herring gull colonies located 51 km apart, in the urban influenced Norwegian Oslofjord. While both colonies are within an urbanised area, the inner fjord is more so, as it is surrounded by Oslo ...
DOI:
10.1016/j.envint.2021.106478

15. Gas Chromatography–Mass Spectrometry Analysis of High-Purity Volatile Inorganic Hydrides

Author:
A. Yu. Sozin; V. A. Krylov; O. Yu. Chernova; T. G. Sorochkina; A. P. Kotkov; N. D. Grishnova; A. I. Skosyrev; G. V. Pushkarev
Source:
Journal of analytical chemistry 2021 v.76 no.5 pp. 535-545
ISSN:
1061-9348
Subject:
siloxanes,   etc   ; analytical chemistry; gas chromatography-mass spectrometry; germanium; quantitative analysis; silicon;     Show all 6 Subjects
Abstract:
... ₄ siloxanes; fluorosiloxanes; oxygen-containing hydrocarbons; sulfur-containing substances; and hydrides of other elements. Gas chromatography–mass spectrometry analysis made it possible to detect the presence of impurities in isotopically enriched silicon and germanium hydrides, which are their molecular isobars. The use of gas chromatography–mass spectrometry in the analysis of high-purity inorganic ...
DOI:
10.1134/S1061934821030126

16. Methylsiloxane occurrence and distribution in free-range poultry eggs near a rural industrial park: Indicators of potential risks to birds

Author:
Zhenwu Tang; Jiali Cheng; Hongmin Yin; Tong Meng; Jiazheng Sun
Source:
Journal of hazardous materials 2021 v.415 pp. 125683
ISSN:
0304-3894
Subject:
siloxanes,   etc   ; chickens; ducks; dust; ecotoxicology; egg albumen; egg yolk; eggs; free range husbandry; progeny; China;     Show all 11 Subjects
Abstract:
... The ecological harm from methylsiloxanes has drawn worldwide attention. This study investigated three cyclic (D₄–D₆) and four linear siloxanes (L₇–L₁₀) in the eggs of free-range poultry collected near a rural industrial park in China and found total concentrations in the range of 19.2–1204 (median, 268) ng/g dry weight. Higher concentrations of methylsiloxanes were observed in chicken eggs than ...
DOI:
10.1016/j.jhazmat.2021.125683

17. A New Stationary Phase for Capillary Gas Chromatography: Calix[4]resorcinarene Functionalized with Imidazolium Cationic Units

Author:
Xiaomin Shuai; Zhiqiang Cai; Xinyu Zhao; Yujie Chen; Qian Zhang; Ziwei Ma; Junjie Hu; Tao Sun; Shaoqiang Hu
Source:
Chromatographia 2021 v.84 no.4 pp. 325-333
ISSN:
0009-5893
Subject:
siloxanes,   etc   ; capillary gas chromatography; chemical species; imidazoles; ionic liquids;     Show all 5 Subjects
Abstract:
... In this work, a novel calix[4]resorcinarene-based ionic liquid (C4RA-2IL) was synthesized, structurally characterized, and statically coated on capillary column as stationary phase for capillary gas chromatography (GC). The column efficiency of the C4RA-2IL column is 3345 plates m⁻¹, which are determined by n-dodecane at 120 °C. Based on its McReynolds constants, the C4RA-2IL column showed moderat ...
DOI:
10.1007/s10337-021-04018-x

18. Reversible Thermochromic Photonic Coatings with a Protective Topcoat

Author:
Weixin Zhang; Albert P. H. J. Schenning; Augustinus J. J. Kragt; Guofu Zhou; Laurens T. de Haan
Source:
ACS applied materials & interfaces 2021 v.13 no.2 pp. 3153-3160
ISSN:
1944-8252
Subject:
siloxanes,   etc   ; color; crosslinking; liquid crystals; phase transition; photons; temperature;     Show all 7 Subjects
Abstract:
... The fabrication of reversible and robust thermochromic coatings remains challenging. In this work, a temperature-responsive photonic coating with a protective topcoat is fabricated. A cholesteric oligosiloxane liquid crystal possessing a smectic-to-cholesteric phase-transition temperature response is synthesized. A planar alignment of its cholesteric phase is possible with blade coating. By stabil ...
DOI:
10.1021/acsami.0c19236

19. Experimental characterization of nozzle flow expansions of siloxane MM for ORC turbines applications

Author:
Giorgia Cammi; Camilla Cecilia Conti; Andrea Spinelli; Alberto Guardone
Source:
Energy 2021 v.218 pp. 119249
ISSN:
0360-5442
Subject:
siloxanes,   etc   ; compressibility; data collection; energy; fluid mechanics; renewable energy sources; temperature; vapors;     Show all 8 Subjects
Abstract:
... . It was investigated whether one parameter only can univocally identify a non-dimensional nozzle expansion. Significant validation data for simulation codes and design tools are provided for MM and for siloxanes in general. ...
DOI:
10.1016/j.energy.2020.119249

20. Disulfide-Containing Polysiloxane with Multicolor Fluorescence and Visible-Light Excitation: Design, Synthesis, and Mechanism Exploration

Author:
Tian Bai; Hongxia Yan; Yunsheng Zhang; Liulong Guo; Yan Zhao
Source:
Journal of physical chemistry 2021 v.125 no.17 pp. 4321-4329
ISSN:
1520-5207
Subject:
siloxanes,   etc   ; biocompatibility; chemical structure; fluorescence; pH; solvents; ultraviolet radiation;     Show all 7 Subjects
Abstract:
... Aggregation-induced emission (AIE) polysiloxane has attracted growing attention in recent years due to its outstanding biocompatibility. However, polysiloxane usually requires high-energy UV light for excitation and exhibits monochromatic blue emission. Moreover, the experimental selection process of polysiloxane with designed features is time-consuming and laborious. So, in this paper, we develop ...
DOI:
10.1021/acs.jpcb.1c00191