Amorphous iron oxide prepared by microwave heating

2000 ◽  
Vol 15 (10) ◽  
pp. 2176-2181 ◽  
Author(s):  
Oleg Palchik ◽  
Israel Felner ◽  
Gina Kataby ◽  
Aharon Gedanken
Keyword(s):  
Phase Transition ◽  
Differential Scanning Calorimetry ◽  
Iron Oxide ◽  
Iron Pentacarbonyl ◽  
Microwave Oven ◽  
The Other ◽  
Scanning Calorimetry ◽  
Amorphous Iron ◽  
Domestic Microwave Oven ◽  
Crystalline Phase Transition

Amorphous iron oxide (Fe2O3) was prepared by the pyrolysis of iron pentacarbonyl [Fe(CO)5] in a modified domestic microwave oven in refluxing chlorobenzene as a solvent under air. The reaction time was 20 min. Partially separated particles of iron oxide, 2–3 nm in diameter, were obtained. The other part showed aggregated spheres with a diameter of 25–40 nm. Differential scanning calorimetry measurements showed an amorphous/crystalline phase transition at about 250 °C.

scholarly journals The Influence of the Nature of Redox-Active Moieties on the Properties of Redox-Active Ionic Liquids and on Their Use as Electrolyte for Supercapacitors

Energies ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 6344
Author(s):  
Philipp S. Borchers ◽  
Patrick Gerlach ◽  
Yihan Liu ◽  
Martin D. Hager ◽  
Andrea Balducci ◽  
...  
Keyword(s):  
Phase Transition ◽  
Differential Scanning Calorimetry ◽  
Ionic Liquid ◽  
Ionic Liquids ◽  
Binary Mixtures ◽  
Thermal Characteristics ◽  
The Other ◽  
Scanning Calorimetry ◽  
Imidazolium Ionic Liquids ◽  
Redox Active

In this work, two new redox-active ionic liquids, one based on 2,2,6,6-tetramethylpiperidine-N-oxide and the other based on 4,4′-bipyridine, are synthesized and characterized. A ferrocene-based redox-active ionic liquid is used for referencing the results. All ionic liquids are formed via salt-metathesis from halogenate to bis(trifluoromethylsulfonyl)imide. Their fundamental thermal characteristics are assessed with differential scanning calorimetry. While the imidazolium ionic liquids show no melting point, the phase transition is well observable for the viologen-based ionic liquid. The properties of the neat redox-active ionic liquids and of binary mixtures containing these ionic liquids (0.1 m) and 1-butyl-1-methyl pyrrolidinium-bis(trifluoromethylsulfonyl)imide have been investigated. Finally, the use of these binary mixtures in combination with activated carbon-based electrodes has been considered in view of the use of these redox-active electrolytes in supercapacitors.

Structures and properties of mixtures of branched chain compounds and lecithin: phytol, α-tocopherol (vitamin E), and phytanic acid

1979 ◽  
Vol 57 (4) ◽  
pp. 458-465 ◽  
Author(s):  
Robert J. Cushley ◽  
Bruce J. Forrest ◽  
Anne Gillis ◽  
Jenifer Tribe
Keyword(s):  
Differential Scanning Calorimetry ◽  
Vitamin E ◽  
Phytanic Acid ◽  
Liquid Crystalline ◽  
Egg Yolk ◽  
Scanning Calorimetry ◽  
Chain Molecules ◽  
Structures And Properties ◽  
Branched Chain ◽  
Crystalline Phase Transition

Phospholipid bilayers containing branched chain molecules, phytol (1), vitamin E (2), and phytanic acid (3), have been investigated by 31P nmr, esr, and differential scanning calorimetry (dsc).A 31P lanthanide induced shift study indicated varying permeabilities to Pr3+ in the order phytanic acid > vitamin E > phytol > egg yolk lecithin alone; the half-lives (in days) were 0.002, 0.14, 0.83, and 6.5, respectively. The activation energy for Pr3+ permeation through the egg yolk lecithin–phytol membrane was found to be 84.9 ± 0.8 kJ.The following esr order parameters, S3, were obtained using the extrinsic spin label, 5-doxylpalmitic acid, in oriented mixed multibilayers: S3 (1) = 0.29, S3 (2) = 0.50, and S3 (3) = 0.02.Differential scanning calorimetry revealed a lowering of the gel–liquid crystalline phase transition temperature, Tc, as the concentration of incorporated isoprenoid compound increases, with eventual disappearance of the endotherm. Specific entropy, s, calculated for dipalmitoyl lecithin +25 mol% 3 is 126 J kg−1 K−1 compared to s = 114.2 J kg−1 K−1 for 1and s = 85 J kg−1 K−1 for 2.

DIFFERENTIAL SCANNING CALORIMETRY INVESTIGATION OF PHASE TRANSITION IN BaZrXTi1-XO3

2009 ◽  
Vol 108 (1) ◽  
pp. 106-115 ◽  
Author(s):  
B. GARBARZ-GLOS ◽  
R. BUJAKIEWICZ-KOROŃSKA ◽  
D. MAJDA ◽  
M. ANTONOVA ◽  
A. KALVANE ◽  
...  
Keyword(s):  
Phase Transition ◽  
Differential Scanning Calorimetry ◽  
Scanning Calorimetry

Synthesis, characterisation and liquid-crystalline phase transition studies on two higher homologues of 4O.m (m=14 and 16) series

2001 ◽  
Vol 709 ◽  
Author(s):  
C. Rama Chandra Prabhu ◽  
V.G.K.M. Pisipati
Keyword(s):  
Phase Transition ◽  
Liquid Crystalline ◽  
Scanning Calorimetry ◽  
First Order ◽  
Smectic A ◽  
Phase Transition Temperatures ◽  
Crystalline Phase Transition ◽  
M 14 ◽  
Enthalpy Data ◽  
Transition Studies

ABSTRACTThe synthesis, characterization and phase transition studies of higher homologues of N(p-nbutoxybenzylidene)p-n-alkylanilines, Viz., 4O.m series (m=14 and 16) are carried out by thermal microscopy, differential scanning calorimetry and density. The compounds exhibit a phase variant of nematic and smectic-A. Density studies reveal a first order nature of IN transitions and a weak first order NA transitions. An estimate of pressure dependence of the phase transition temperatures using the volume and enthalpy data are presented. A comparison of these results with other reported results in nO.m and other compounds are presented.

Dependence of Phase Transition of a Bent-Core Liquid Crystal on the Heating Rate

2010 ◽  
Vol 663-665 ◽  
pp. 787-790 ◽  
Author(s):  
Qing Lan Ma ◽  
Yuan Ming Huang
Keyword(s):  
Phase Transition ◽  
Differential Scanning Calorimetry ◽  
Liquid Crystal ◽  
Optical Microscopy ◽  
Heating Rate ◽  
Broad Peak ◽  
Crystal Phase ◽  
Scanning Calorimetry ◽  
Polarized Optical Microscopy ◽  
Crystal Compound

A bent-core liquid crystal compound N,N-bis (4-propoxybenzylidene)benzene- 1,3-diamine was synthesized. Phase transition properties of the synthesized compound with the deferent heating rate were characterized with differential scanning calorimetry and polarized optical microscopy. , respectively. Our results demonstrated that the bent-core compound exhibited the completely undivided multi-phases in heating-rate ranges from 1oC/min to 6oC/min while it showed a broad-peak crystal phase in higher heating-rate ranges of 7-10oC/min for the first heating.

SAXS Study of Selected Cationic Surfactant Influence on the DSPC-Based Model Phospholipid System

2007 ◽  
Vol 130 ◽  
pp. 257-262
Author(s):  
Maciej Kozak ◽  
Ludwik Domka ◽  
Stefan Jurga
Keyword(s):  
Phase Transition ◽  
Differential Scanning Calorimetry ◽  
Small Angle ◽  
Phase Behaviour ◽  
Lamellar Phase ◽  
Scanning Calorimetry ◽  
X Ray ◽  
X Ray Scattering ◽  
Hydrocarbon Chains ◽  
Main Transition

The phase behaviour of lipid bilayer systems prepared with 1,2-distearoyl-sn-glycero-3- phosphocholine (DSPC) with dodecyldimethyl(benzyloxymethyl)ammonium chloride (BzMDDAC) (at concentrations 0.1, 1 and 5%) has been studied by small angle X-ray scattering and differential scanning calorimetry. The SAXS and DSC results of the hydrated 10% DSPC revealed one typical phase transition corresponding to melting of the hydrocarbon chains at 55 °C. In the system of 10% DSPC - 0.1 % BzMDDAC the main transition was somewhat shifted towards lower temperatures, while at 1% concentration of BzMDDAC in the mixture, the lamellar phase disappeared, as evidenced by SAXS and DSC. The increase in BzMDDAC concentration to 5% in the mixture with 10% DSPC resulted in formation of a new lamellar phase.

Sign in / Sign up

Export Citation Format

Share Document