Infrared characterisation of acetonitrile and propionitrile aerosols under Titan's atmospheric conditions

2017 ◽  
Vol 19 (4) ◽  
pp. 2915-2925 ◽  
Author(s):  
C. Ennis ◽  
R. Auchettl ◽  
M. Ruzi ◽  
E. G. Robertson
Keyword(s):  
Particle Size ◽  
Infrared Spectroscopy ◽  
Atmospheric Conditions ◽  
Diffusion Kinetics ◽  
Insight Into ◽  
Ice Morphology

Acetonitrile and propionitrile aerosols were generated under simulated Titan conditions where new insight into the ice morphology, particle size and formation/diffusion kinetics has been extracted by online infrared spectroscopy.

scholarly journals Changes of Pd Oxidation State in Pd/Al2O3 Catalysts Using Modulated Excitation DRIFTS

Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 116
Author(s):  
Gian Luca Chiarello ◽  
Ye Lu ◽  
Miren Agote-Arán ◽  
Riccardo Pellegrini ◽  
Davide Ferri
Keyword(s):  
Particle Size ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Oxidation State ◽  
Diffuse Reflectance ◽  
X Ray ◽  
Spectral Changes ◽  
Diffuse Reflectance Infrared ◽  
X Ray Absorption ◽  
Reversible Reduction

Infrared spectroscopy is typically not used to establish the oxidation state of metal-based catalysts. In this work, we show that the baseline of spectra collected in diffuse reflectance mode of a series of Pd/Al2O3 samples of increasing Pd content varies significantly and reversibly under alternate pulses of CO or H2 and O2. Moreover, these baseline changes are proportional to the Pd content in Pd/Al2O3 samples exhibiting comparable Pd particle size. Similar measurements by X-ray absorption spectroscopy on a different 2 wt.% Pd/Al2O3 confirm that the baseline changes reflect the reversible reduction-oxidation of Pd. Hence, we demonstrate that changes in oxidation state of metal-based catalysts can be determined using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and that this behavior is part of the spectral changes that are returned by experiments under operando conditions.

scholarly journals Low temperature synthesis and characterization of Mn3O4 nanoparticles

2007 ◽  
Vol 5 (1) ◽  
pp. 169-176 ◽  
Author(s):  
Abdülhadi Baykal ◽  
Yüksel Köseoğlu ◽  
Mehmet Şenel
Keyword(s):  
Particle Size ◽  
Infrared Spectroscopy ◽  
Low Temperature ◽  
Synthesis And Characterization ◽  
Low Temperature Synthesis ◽  
Temperature Synthesis ◽  
X Ray ◽  
Peak Broadening ◽  
Mn3o4 Nanoparticles

AbstractHeating hydrous manganese (II) hydroxide gel at 85 °C for 12 hours produces Mn3O4 nanoparticles. They were characterized by X-ray powder diffraction (XRD) and infrared spectroscopy (FTIR). The particle size estimated from the SEM and X-ray peak broadening is approximately 32 nm, showing them to be nanocrystalline. EPR measurements confirm a typical Mn2+signal with a highly resolved hyperfine structure.

Revisiting graphene–polymer nanocomposite for enhancing anticorrosion performance: a new insight into interface chemistry and diffusion model

Nanoscale ◽  
2018 ◽  
Vol 10 (26) ◽  
pp. 12612-12624 ◽  
Author(s):  
Dipak Dutta ◽  
Andita Nataria Fitri Ganda ◽  
Jui-Kung Chih ◽  
Cheng-Chun Huang ◽  
Chung-Jen Tseng ◽  
...  
Keyword(s):  
Galvanic Corrosion ◽  
Polymer Nanocomposite ◽  
Diffusion Kinetics ◽  
Interfacial Chemistry ◽  
Interface Chemistry ◽  
Graphene Nanocomposite ◽  
Kinetics Of ◽  
And Diffusion ◽  
Insight Into ◽  
Percolation Network

The interfacial chemistry and diffusion kinetics of a polymer–graphene nanocomposite anticorrosion coating were studied to minimize galvanic corrosion facilitated by the formation of an interconnected graphene percolation network.

Characterization of Electrophoretic Lipoprotein Fractions: Immunochemical and Electron Microscopic Studies

1972 ◽  
Vol 18 (6) ◽  
pp. 534-538
Author(s):  
Mario Werner ◽  
Albert L Jones
Keyword(s):  
Electron Microscopy ◽  
Particle Size ◽  
Electrophoretic Pattern ◽  
Electron Microscopic ◽  
Lipoprotein Subfractions ◽  
New Techniques ◽  
Microscopic Studies ◽  
Insight Into

Abstract To improve the characterization of electrophoretic lipoprotein subfractions, we developed two new techniques for analyzing lipoproteins after electrophoresis on thin agarose layers. Overlay with antisera exactly localizes specific apoproteins without any distortion caused by antigen diffusion; electron microscopy of eluted fractions determines the varying particle-size distribution. Applied together, these methods can detect individual differences between hyperlipemic samples that are not immediately apparent in the electrophoretic pattern, and should provide valuable new insight into the classification of hyperlipoproteinemias.

scholarly journals Thermodynamics of Pyrocumulus: A Conceptual Study

2018 ◽  
Vol 146 (8) ◽  
pp. 2579-2598 ◽  
Author(s):  
Kevin J. Tory ◽  
William Thurston ◽  
Jeffrey D. Kepert
Keyword(s):  
Full Range ◽  
Fire Behavior ◽  
Atmospheric Conditions ◽  
Neutral Buoyancy ◽  
Lightning Strikes ◽  
Plume Temperature ◽  
Conceptual Study ◽  
Lifting Condensation Level ◽  
In Fire ◽  
Insight Into

Abstract In favorable atmospheric conditions, fires can produce pyrocumulonimbus cloud (pyroCb) in the form of deep convective columns resembling conventional thunderstorms, which may be accompanied by strong inflow, dangerous downbursts, and lightning strikes that can produce dangerous changes in fire behavior. PyroCb formation conditions are not well understood and are difficult to forecast. This paper presents a theoretical study of the thermodynamics of fire plumes to better understand the influence of a range of factors on plume condensation. Plume gases are considered to be undiluted at the fire source and approach 100% dilution at the plume top (neutral buoyancy). Plume condensation height changes are considered for this full range of dilution and for a given set of factors that include environmental temperature and humidity, fire temperature, and fire-moisture-to-heat ratios. The condensation heights are calculated and plotted as saturation point (SP) curves on thermodynamic diagrams. The position and slope of the SP curves provide insight into how plume condensation is affected by the environment thermodynamics and ratios of fire heat to moisture production. Plume temperature traces from large-eddy model simulations added to the diagrams provide additional insight into plume condensation heights and plume buoyancy at condensation. SP curves added to a mixed layer lifting condensation level on standard thermodynamic diagrams can be used to identify the minimum plume condensation height and buoyancy required for deep, moist, free convection to develop, which will aid pyroCb prediction.

Improved Crystallinity of Zinc Sulfide Nanoparticles in Aqueous Environment

2005 ◽  
Vol 879 ◽  
Author(s):  
Navendu Goswami ◽  
P. Sen
Keyword(s):  
Particle Size ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Fourier Transform Infrared Spectroscopy ◽  
Zinc Sulfide ◽  
Structural Transformation ◽  
Powder Diffraction ◽  
Aqueous Environment ◽  
X Ray ◽  
Zinc Sulfide Nanoparticles

AbstractZinc sulfide nanoparticles, prepared employing a non-equilibrium route, are investigated for surface related effects. Water has been shown to induce a structural transformation in nanoparticles prepared this way, which is not related to their particle size. Employing Fourier transform infrared spectroscopy and x-ray powder diffraction, we show here the importance of S-H interaction in the buildup to the final ZnS structure of these nanoparticles. These particles hold promise as water sensors.

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