Parcourir Faculté des arts et des sciences – Département de chimie – Travaux et publications par titre
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Linking the chemical speciation of cerium to its bioavailability in water for a freshwater alga
(Wiley, 2015-03-13)Over the past decade, researchers have begun to use metals of the lanthanide family for numerous applications, including liquid crystal display (LCD) screens, optical fibers, and laser technology. Unfortunately, little is presently known about their ... -
Metal-ligand bonding in six-coordinate d-block complexes probed by luminescence spectroscopy at variable pressure
(De Gruyter, 2022)Luminescence spectra measured at variable pressure can reveal unique insight on ground- and emitting state properties of transition metal compounds. This chapter summarizes illustrative results for chromium(III) complexes with the d3 electron configuration ... -
Metal–ligand interactions and salt bridges as sacrificial bonds in mussel byssus-derived materials
(American Chemical Society, 2016-09-02)The byssus that anchors mussels to solid surfaces is a protein-based material combining strength and toughness as well as a self-healing ability. These exceptional mechanical properties are explained in part by the presence of metal ions forming ... -
Mixtures of rare earth elements show antagonistic interactions in Chlamydomonas reinhardtii
(Elsevier, 2021-06-14)In order to better understand the environmental risks of the rare earth elements (REEs), it is necessary to determine their fate and biological effects under environmentally relevant conditions (e.g. at low concentrations, REE mixtures). Here, the ... -
Molecular origin of the odd–even effect of macroscopic properties of n-Alkanethiolate self-assembled monolayers : bulk or interface?
(American Chemical Society, 2020-06-29)Elucidating the influence of the monolayer interface versus bulk on the macroscopic properties (e.g., surface hydrophobicity, charge transport, and electron transfer) of organic self-assembled monolayers (SAMs) chemically anchored to metal surfaces is ... -
Molecular-level photo-orientation insights into macroscopic photo-induced motion in azobenzene-containing polymer complexes
(American Chemical Society, 2021-07-13)As part of continuing efforts to deepen the understanding of photo-induced mass transport in azo-containing polymers, we compared the diffraction efficiency (DE) during surface-relief grating (SRG) inscription, photo-induced molecular orientation (<P2>), ... -
Molecular-level study of photoorientation in hydrogen-bonded azopolymer complexes
(American Chemical Society, 2018-01-25)To optimize azobenzene-containing materials for applications such as rewritable waveguides and holographic data storage, it is imperative to understand the effect of the azobenzene structure on the photoresponse of the material. Supramolecular ... -
Near-infrared vibrational overtone spectra of teepleite, Na2B(OH)4Cl, and its deutero analog : research report
(2021-12-05)Single crystals of the naturally occurring mineral teepleite, Na2B(OH)4Cl, and its deuterated analog were grown and their polarized near-infrared absorption spectra recorded at 10 K. The spectra show three intense, sharp sets of O–H and O–D overtone ... -
On the importance of noncrystalline phases in semicrystalline electrospun nanofibers
(American Chemical Society, 2021-11-18)Tailoring the properties of electrospun fibers requires a detailed understanding and control of their microstructure. We investigate the structure/property relationships in fabrics of randomly aligned fibers of polylactide, a prevalent biopolymer, ... -
Orientation and partial disentanglement in individual electrospun fibers : diameter dependence and correlation with mechanical properties
(American Chemical Society, 2015-06-29)Electrospun fibers are versatile materials that exhibit unusual and tunable properties when studied at the single fiber level, including an exponential increase in modulus with a decreasing diameter toward the nanoscale. Understanding the detailed ... -
Photoactive/passive molecular glass blends : an efficient strategy to optimize azomaterials for surface relief grating inscription
(American Chemical Society, 2016-12-15): Irradiation of azomaterials causes various photophysical and photomechanical effects that can be exploited for the preparation of functional materials such as surface relief gratings (SRGs). Herein, we develop and apply an efficient strategy to ... -
Photocontrol of supramolecular azo-containing block copolymer thin films during dip-coating : toward nanoscale patterned coatings
(American Chemical Society, 2019-05-07)Dip-coating allows nanostructured block copolymer (BCP) thin film fabrication in a fast and facile one-step process. It can also be coupled with external controls, such as illumination. Herein, we expose several design principles that enable photocontrol ... -
Polarized raman analysis of polymer chain orientation in ultrafine individual nanofibers with variable low crystallinity
(American Chemical Society, 2018-10-26)Recent mechanical studies of ultrafine electrospun polymer nanofibers showed they can simultaneously possess high strength and toughness attributed to high degree of chain alignment coupled with low crystallinity. Quantitative analysis of macromolecular ... -
Pressure-induced change of d-d luminescence energies, vibronic structure and band intensities in transition metal complexes
(Taylor and Francis, 2006-08-16)The effects of hydrostatic pressure on the luminescence spectra of tetragonal transition metal complexes with nondegenerate electronic ground states are analyzed quantitatively by means of models based on potential energy surfaces defined along normal ... -
Probing interfacial interactions and dynamics of polymers enclosed in boron nitride nanotubes
(Wiley, 2021-11-23)Understanding interfacial interactions in polymer systems is crucial for their applicability for instance in adhesives and coatings. Enclosing polymers in a cylindrical volume provides a system for studying interactions dictated by a continuous ... -
Quantification and characterization of Ti-, Ce- and Ag5 nanoparticles in global surface waters and precipitation
(American Chemical Society, 2021-06-28)Nanoparticle (NP) emissions to the environment are increasing as a result of anthropogenic activities, prompting concerns for ecosystems and human health. In order to evaluate the risk of NPs, it is necessary to know their concentrations in various ... -
Quantification of ZnO nanoparticles and other Zn containing colloids in natural waters using a high sensitivity single particle ICP-MS
(Elsevier, 2019-03-08)Inductively coupled plasma mass spectrometry in single particle mode (SP-ICP-MS) is becoming a powerful tool of choice for the quantification and characterization of metallic nanoparticles (NP) at very low concentrations. Nonetheless, this technique ... -
Quantifying polymer chain orientation in strong and tough nanofibers with low crystallinity : towards next generation nanostructured superfibers
(American Chemical Society, 2019-04-19)Advanced fibers revolutionized structural materials in the second half of the 20th century. However, all high-strength fibers developed to date are brittle. Recently, pioneering simultaneous ultrahigh strength and toughness were discovered in fine (<250 ... -
Raman spectroscopy of individual poly(ethylene oxide) electrospun fibers : effect of the collector on molecular orientation
(Elsevier, 2016-09-06)Electrospun fibers are complex polymeric materials with a typical diameter of a few hundred nanometers that are often frozen in out-of-equilibrium states due to the fast solvent evaporation and high elongational forces during the process. Their ... -
Release of TiO2 nanoparticles from painted surfaces in cold climates : characterization using a high sensitivity single-particle ICP-MS
(Royal Society of Chemistry, 2020)Paints and coatings represent one of the major applications of TiO2 nanoparticles (NPs). While it has been previously shown that NPs are released from painted surfaces, there is still a lack of experimental data on their release rates under natural ...