Comparative Specular X-ray Reflectivity, Positron Annihilation Lifetime Spectroscopy, and Incoherent Neutron Scattering Measurements of the Dynamics in Thin Polycarbonate Films

2004 ◽  
Vol 37 (8) ◽  
pp. 2890-2900 ◽  
Author(s):  
Christopher L. Soles ◽  
Jack F. Douglas ◽  
Wen-li Wu ◽  
Huagen Peng ◽  
David W. Gidley
Keyword(s):  
Neutron Scattering ◽  
Positron Annihilation ◽  
Positron Annihilation Lifetime Spectroscopy ◽  
X Ray ◽  
Positron Annihilation Lifetime ◽  
Incoherent Neutron Scattering ◽  
Scattering Measurements ◽  
Incoherent Neutron

scholarly journals Morphology of Thin Film Composite Membranes Explored by Small-Angle Neutron Scattering and Positron-Annihilation Lifetime Spectroscopy

Membranes ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 48 ◽  
Author(s):  
Vitaliy Pipich ◽  
Marcel Dickmann ◽  
Henrich Frielinghaus ◽  
Roni Kasher ◽  
Christoph Hugenschmidt ◽  
...  
Keyword(s):  
Thin Film ◽  
Neutron Scattering ◽  
Positron Annihilation ◽  
Small Angle ◽  
Small Angle Neutron Scattering ◽  
Positron Annihilation Lifetime Spectroscopy ◽  
Film Composite ◽  
Positron Annihilation Lifetime ◽  
Thin Film Composite

The morphology of thin film composite (TFC) membranes used in reverse osmosis (RO) and nanofiltration (NF) water treatment was explored with small-angle neutron scattering (SANS) and positron-annihilation lifetime spectroscopy (PALS). The combination of both methods allowed the characterization of the bulk porous structure from a few Å to µm in radius. PALS shows pores of ~4.5 Å average radius in a surface layer of about 4 μm thickness, which become ~40% smaller at the free surface of the membranes. This observation may correlate with the glass state of the involved polymer. Pores of similar size appear in SANS as closely packed pores of ~6 Å radius distributed with an average distance of ~30 Å. The main effort of SANS was the characterization of the morphology of the porous polysulfone support layer as well as the fibers of the nonwoven fabric layer. Contrast variation using the media H2O/D2O and supercritical CO2 and CD4 identified the polymers of the support layers as well as internal heterogeneities.

Incoherent Neutron Scattering Measurements on KDP

1992 ◽  
Vol 61 (8) ◽  
pp. 2619-2623 ◽  
Author(s):  
Susumu Ikeda ◽  
Kaoru Shibata ◽  
Yusuke Nakai ◽  
Peter W. Stephens
Keyword(s):  
Neutron Scattering ◽  
Incoherent Neutron Scattering ◽  
Scattering Measurements ◽  
Incoherent Neutron

Similarity of Vibrational Spectra of High Density Amorphous Ice and High Pressure Phase Ice Vi

1994 ◽  
Vol 376 ◽  
Author(s):  
A.I. KOLESNIKOV
Keyword(s):  
High Pressure ◽  
Hydrogen Bonds ◽  
Neutron Scattering ◽  
Amorphous Phase ◽  
Vibrational Spectra ◽  
Amorphous Ice ◽  
Incoherent Neutron Scattering ◽  
Scattering Measurements ◽  
Pressure Phase ◽  
Incoherent Neutron

ABSTRACTInelastic incoherent neutron scattering measurements on the hdaice, ice Ih and high-pressure phases ice VI and ice VIII revealed similarity between the amorphous phase and crystalline ice VI and led to the new proposition that hda ice consists of two interpenetrating hydrogen-bonded networks with no hydrogen bonds between “sublattices”.

scholarly journals Convenient Preparation of Graphene Oxide from Expandable Graphite and Its Characterization by Positron Annihilation Lifetime Spectroscopy

2019 ◽  
Vol 5 (1) ◽  
pp. 6 ◽  
Author(s):  
Guido Panzarasa ◽  
Giovanni Consolati ◽  
Marco Scavini ◽  
Mariangela Longhi ◽  
Fiorenza Quasso
Keyword(s):  
Graphene Oxide ◽  
Positron Annihilation ◽  
Nitrogen Adsorption ◽  
Positron Annihilation Lifetime Spectroscopy ◽  
Expandable Graphite ◽  
X Ray Diffraction ◽  
X Ray ◽  
Positron Annihilation Lifetime ◽  
Convenient Preparation ◽  
Extract Information

Graphene oxide (GO) is conveniently prepared from expandable graphite using a simplified Hummers’ method. The product is thoroughly characterized by usual techniques (UV-vis, Fourier-transform infrared (FTIR) and Raman spectroscopies, zeta potential, electron microscopy, X-ray diffraction, nitrogen adsorption) to confirm the success of synthesis. Positron annihilation lifetime spectroscopy (PALS) is then used to extract information on the microenvironment in between the layers of graphene oxide.

A Broad Perspective on the Dynamics of Highly Confined Polymer Films

2001 ◽  
Vol 710 ◽  
Author(s):  
Christopher L. Soles ◽  
Jack F. Douglas ◽  
Wen-Li Wu ◽  
Huagen Peng ◽  
David W. Gidley
Keyword(s):  
Thin Film ◽  
Broad Perspective ◽  
X Ray ◽  
Positron Annihilation Lifetime ◽  
Incoherent Neutron Scattering ◽  
Thermal Expansion Coefficients ◽  
Chemically Amplified ◽  
Expansion Coefficients ◽  
Technological Significance ◽  
Incoherent Neutron

ABSTRACTThe manner in which the dynamics of a polymer are affected by thin film confinement is of technological significance, impacting thin film applications such as lubricants, adhesives, and chemically amplified photoresists. In this manuscript we use specular X-ray reflectivity (SXR), beam positron annihilation lifetime spectroscopy (PALS), and incoherent neutron scattering (INS) to study the influence of thin film confinement on the apparent glass transition temperature Tg and the thermal expansion coefficients of thin polycarbonate (PC) films. Both the SXR and PALS indicate a significant suppression of Tg when the film thickness becomes less than 200 Å. However, the INS measurements suggest an increase in the apparent Tg below this same length scale. These disparate estimates of the thin film Tg seem to indicate that each technique is sensitive to slightly different aspects of the glass formation process. However, all three agree that thin film confinement results in reduced thermal motion, regardless of the precise temperature that is ‘designated' as the thin film Tg.

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