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Between 2010 and 2015, the Bellechasse Regional County Municipality (Bellechasse RCM) was affected by particularly noxious odors issuing from its Municipal Solid Waste Landfill (Bellechasse RCM MSWL) in Armagh, Canada. A study carried out in 2015-2016 by Centre de recherche industrielle du Québec (CRIQ) confirmed that it was still possible for hydrogen sulfide (H2S) emissions to cause odor issues in and around the site. The experimental project carried out by CRIQ in cooperation with Bellechasse RCM, Englobe, Quebec City and the Regroupement des récupérateurs et des recycleurs de matériaux de construction et de démolition du Québec (represented by AIM Éco-centre) made it possible to test three (3) different industrial residue as an alternative cover materials on site and study how they controlled H2S emissions, volatile organic compounds (VOCs) and odors at the Bellechasse RCM’s landfill. The site was monitored from November 2016 to September 2017 to confirm the effectiveness of alternative biofiltration cover materials (soil + compost), domestic waste incineration bottom ash and 0 to 2.5-inch concrete residues and to compare the results with the sand cover currently used as the cover material. Effectiveness was determined by measuring the Area Source Emission Rate (ASER) with a 3 m x 3 m static flux chamber developed for the project. Methane measurements were concomitantly taken to confirm that the biogas could escape through the cover materials. The monitoring results made it possible to demonstrate that domestic waste incineration bottom ash as well as 0-2.5 in. concrete received the highest load of H2S and showed an H2S capture performance of greater than 83ϿFor volatile organic compounds, materials such as 0-2.5 in. concrete and the alternative biofiltration cover materials were most effective for capture (greater than 73Ͽfor the highest loads. The lowest content of CH4 after covering was measured for the alternative cover materials. The site where the incineration bottom ash was used managed to decrease odors by ±200 odor units. Overall, we have demonstrated in this project, the capacity of different alternative cover materials under real condition for the control of gas emissions from landfill.

An approach using physical vapor deposition technology to produce nanoparticles (NPs) containing radioactive atoms and the methodology to transfer them in pure water is investigated. NPs are synthesized by magnetron sputtering at high pressure and radioactive atoms are loaded on magnetron cathodes prior to sputtering. The technique was tested for gold cathode loaded with Co and Au. Linked to biological vector molecules, the nanoparticles can be used to enhance diagnostic sensitivity in medical imaging or to treat cancer.Sizes and morphologies of the NPs were analyzed by electron microscopy, UV-Visible spectroscopy and atomic absorption spectroscopy. Results show well dispersed NPs with sizes varying between 5 and 10. nm. Activities of these NPs were measured with a CAPINTEC well counter and a High Purity Germanium detector system. Centrifugation analyses also demonstrate that the choice of the activated metal which can be alloyed with NPs plays an important role in the synthesis. This was confirmed by the Au-Co phase diagram that shows that cobalt cannot be included efficiently in the gold NPs conversely to gold. © 2011 Elsevier B.V.

In this work, we investigate the surface reactivity of substrates coated with thin layers (estimated thickness ≤30nm) of plasma polymerized allylamine films (PPAA), an amine-functionalized polymer deposited by plasma-enhanced chemical vapor deposition (PECVD) with radiofrequency (RF) discharges. Our results show that very thin layers, or islands, can retain on their surface molecules that are able to react through their NH functions. We have tested and assessed by X-Ray Electron Spectroscopy (XPS) and Quartz Crystal Microbalance (QCM) the surface density of chemical functions vs. layer thicknesses by using chemical derivatization with two types of agents: imine formation by a reaction of primary amine from the coating with aldehyde (Pentafluorobenzaldehyde, PFBA) and amide-bond formation by reaction with an activated carboxylic group (Succinimidyl Succinate Terminated Polyethylene glycol, EGSS). Results show that the PPAA coatings-even for very thin layers of a few nanometers-promote the chemisorption of the tagging molecules. The aging under air and evolution of reactive amine surface concentration with time under air are also presented. © 2010 Elsevier B.V.

Surface properties of nanoparticles to be used for radioimmunotherapy need to be optimized to allow antibody conjugation while ensuring biocompatibility. We aimed to investigate cell adhesion and proliferation onto different coatings to be used for nanoparticles. C, CH or SiO coatings deposited onto glass coverslips by magnetron deposition as well as nitrogen functionalized materials synthetized using different reactive sputtering conditions and PPAA (plasma polymerized allylamine) coating, were compared. Amine functionalization did increase hydrophilicity in all the materials tested. Biocompatibility was assessed by measuring cell viability, morphology, attachment, spreading, and pro-inflammatory cytokine secretion. The results show that C and CN were the most biocompatible substrates while SiO and SiO N were the most toxic materials. PPAA coatings displayed unexpectedly an intermediate biocompatibility. A correlation could be observed between wettability and cell proliferation except for C coated surface, indicating that more complex processes than hydrophilicity alone are taking place that affect cell functions. © Springer Science+Business Media, LLC 2011.

High-pressure DC magnetron sputtering was used for the deposition of cobalt on amorphous carbon (a-C) and SiO. Deposition conditions, substrate surface morphology and annealing parameters are investigated in order to promote the synthesis of large arrays of nanoparticles, with regular size and shape. Uniformly distributed Co nanoparticles a few nanometers in size were formed under annealing at 700°C in H. Particle nucleation and growth are discussed based on X-ray photoelectron spectroscopy, transmission and scanning electron microscopy and kinetic Monte Carlo modeling (KMC). © Springer-Verlag 2010.

Large quantities of gold nanoparticles (Au NPs) were prepared by physical vapour deposition (PVD) technique. The produced nanoparticles were transferred into water solutions [containing 1% of carboxymethylcellulose (CMC)]. To achieve this resuspension, the Au NPs were embedded in a NaCl matrix, also deposited by PVD. In order to avoid the instantaneous and irreversible aggregation of the Au NPs, a surface modification needs to be performed, for example, by coating the metallic particles with plasma polymerized polymers. In this work, we present selected conditions allowing the production of aqueous solutions of Au NPs with small diameters (ca. 10 nm). The whole process is carried out thanks to a fully automatic plasma deposition system, allowing the production of high concentration of gold nanoparticles.

Due to its surface properties, especially the presence of amine groups, plasma polymerized allylamine (PPAA) is involved in a large range of applications. Most of them are related to biology and biochemistry. In this work, we demonstrate a quick and simple way to produce PPAA thin films by conventional DC magnetron sputtering. To the best of our knowledge, this is the first method not involving radiofrequency (RF) or microwave discharges. In this paper, we show preliminary characterizations on the produced films (bulk analysis) carried out by ion beam techniques. The Hydrogen content in the whole layers was measured by ERD. The surface composition was probed by XPS on pentafluorobenzaldehyde (PFBA) derivatized films: the maximum concentration of amine groups is 1.6%. (C) 2008 Elsevier B.V. All rights reserved.

Nanocomposites based on an ethylene-vinyl acetate copolymer (27 wt.-% vinyl acetate) and multiwall carbon nanotubes (MWNTs) have been prepared by melt blending and their thermal degradation and flame retardant properties have been evaluated. Special attention has been paid to the influence of the nanotube nature on the flammability properties and more particularly on the time to ignition (TTI) as measured by cone calorimetry. It has been shown that there is a strong influence of the nature of carbon nanotubes on the fire behaviour of the composites, especially previous MWNTs crushing proved to substantially delay the TTI while maintaining much reduced heat release rate (HRR). Such a remarkable behaviour might be explained by the chemical reactivity of radical species present at the surface/extremities of crushed MWNTs during the combustion process.

Hybrid WO3–CNT (carbon nanotube) films were prepared in two steps: in the first step, the drop coating method was employed for coating silicon substrates with a MWCNT (multiwalled CNT) film prepared with oxygen plasma functionalized MWCNTs; in the second step, a layer of WO3 nanoparticles was deposited over the MWCNT film by using an advanced gas deposition unit. The WO3 nanoparticles are formed by condensation. SEM images show that the morphology of the hybrid films is characterized by an overlayer formed from WO3 particles anchored at the surface of a well-dispersed MWCNT underlayer. TEM images show that the hybrid films are composed of a WO3 matrix supported through a dispersed mesh of CNTs—the CNTs act as internal pillars. This morphology increases the surface area for gas interaction.

Organic polymers - carbon nanotubes nanocomposites are synthesized either by mechanical mixing of the two components or by covalently linking the nanotubes to the matrix. The various procedures will be overviewed and the determining factors will be identified for the best mechanical properties of the composites. On the other hand, it will be shown that for highest electrical conductivity much smaller amounts of carbon nanotubes are needed if the nanotubes can be aligned. The thermal conductivity of the nanocomposites will also be overviewed. Finally, together with nanoclay particles, nanotubes are inducing remarkable flame retardant properties in the nanocomposites materials.

Carbon nanotubes focus the attention of many scientists because of their huge potential of industrial applications, but there is a paucity of information on the toxicological properties of this material. The aim of this experimental study was to characterize the biological reactivity of purified multi-wall carbon nanotubes in the rat lung and in vitro. Multi-wall carbon nanotubes (CNT) or ground CNT were administered intratracheally (0.5, 2 or 5 mg) to Sprague-Dawley rats and we estimated lung persistence, inflammation and fibrosis biochemically and histologically. CNT and ground CNT were still present in the lung after 60 days (80% and 40% of the lowest dose) and both induced inflammatory and fibrotic reactions. At 2 months, pulmonary lesions induced by CNT were characterized by the formation of collagen-rich granulomas protruding in the bronchial lumen, in association with alveolitis in the surrounding tissues. These lesions were caused by the accumulation of large CNT agglomerates in the airways. Ground CNT were better dispersed in the lung parenchyma and also induced inflammatory and fibrotic responses. Both CNT and ground CNT stimulated the production of TNF-alpha in the lung of treated animals. In vitro, ground CNT induced the overproduction of TNF-alpha by macrophages. These results suggest that carbon nanotubes are potentially toxic to humans and that strict industrial hygiene measures should to be taken to limit exposure during their manipulation.

Morphological and rheological properties of new ternary nanocomposites based on ethylene vinyl acetate copolymers (EVA), commercial organo-modified clays (organoclays) and purified multi-walled carbon nanotubes (MWNTs), prepared via direct melt blending, have been evaluated. For sake of comparison, the corresponding binary compositions, i.e., EVA filled with either organoclays or MWNTs, have been investigated as well. While extensive exfoliation can be observed for binary EVA/clay nanocomposites, the addition of MWNTs appears to limit clay exfoliation. Rheological properties show that both clay and MWNTs increase the elastic modulus of the nanocomposites, reflecting the high degree of nanoparticle interconnectivity that can be found in these materials.

We report on the controllable growth of individual, uniform carbon nanotubes using thermal chemical vapor deposition (CVD). We performed a detailed study of the various factors influencing the growth of single nanotubes. In particular, we investigated the role played by catalyst layer thickness, catalyst dot size, deposition temperature, and gas source pressure on the growth process of straight, single nanotubes. Straight, individual nanotubes with uniform diameter can be obtained by decomposition of 0.1 mbar of acetylene at a temperature of 800 °C over a 5 nm thick nickel film that is patterned into square dots with dimensions below 500 nm. We compare the performance of thermal CVD and of plasma enhanced CVD for growing individual nanotubes.

In this study, a new type of materials, based on ethylene–vinyl acetate (EVA) copolymers, commercial organo-modified clays (organoclays) and multi-walled carbon nanotubes (MWNTs) has been prepared via direct melt blending. Both crude and purified MWNTs have been investigated. Thermal, flame retardant and tensile properties of the resulting new ternary nanocomposites have been measured and compared to the corresponding binary systems, i.e., EVA filled with either clays or carbon nanotubes. This new family of composites exhibits enhanced properties even at very low filler level usually inferior to 5 wt%. Interestingly, a synergistic effect arising from the combination of MWNTs and organoclays has been evidenced in some cases.

In this paper, the chemical functionalization of multi-walled carbon nanotubes by a fluorinated trichlorosilane ((tridecafluoro-1,1,2,2-tetrahydrooctyl)trichlorosilane) is investigated. The chlorosilane has been shown to react with carboxylic acid moieties, created by an oxidative process on the nanotube walls, as well as with alcohol groups obtained by a reductive reaction of these previous oxidized nanotubes. The derivatizations were directly confirmed by x-ray photoelectron spectroscopy and thermogravimetry analyses. Little difference in the functionalization was observed for the oxidized or reduced nanotubes. However, the amount of grafted silane seems to be slightly more important when the silanization is carried out with reduced nanotubes.

International audience; Adherent-invasive Escherichia coil (AIEC) have previously been shown to induce gut inflammation in patients with Crohn's disease (CD). We developed a set of mannosides to prevent AIEC attachment to the gut by blocking the FimH bacterial adhesin. The crystal structure of the FimH lectin domain in complex with a lead thiazolylaminomannoside highlighted the preferential position for pharmacomodulations. A small library of analogues showing nanomolar affinity for FimH was then developed. Notably, AIEC attachment to intestinal cells was efficiently prevented by the most active compound and at around 10000-fold and 100-fold lower concentrations than mannose and the potent FimH inhibitor heptylmannoside, respectively. An ex vivo assay performed on the colonic tissue of a transgenic mouse model of CD confirmed this antiadhesive potential. Given the key role of AIEC in the chronic intestinal inflammation of CD patients, these results suggest a potential antiadhesive treatment with the FimH inhibitors developed.

Driving the equilibrium between selenides and osmium(VIII) reagents with selenoxides and osmium(VI) by a subsequent reaction (rearrangement of allyl selenoxides to allyl alcohols or addition of osmium(VIII) species on CC double bonds) to one side, allows the transformation of methyl geranyl selenides to linalool and of methyl citronellyl selenoxide to 6,7-dihydroxy citronellyl selenide.

Releases of creosote and pentachlorophenol (PCP) at a New Brighton, Minnesota wood treatment facility, resulted in widespread soil and groundwater contamination. Site investigations lead to the facility’s inclusion on the National Priorities List (NPL), and the Minnesota Pollution Control Agency was designated lead regulatory agency. Biological treatment was the preferred remedy for 18,000 yd3 of contaminated soil, and Biogenie was contracted to design, construct and operate an ex situ Biopile to achieve the remedial objectives.

Driving the equilibrium between selenides and osmium(VIII) reagents with selenoxides and osmium(VI) by a subsequent reaction (rearrangement of allyl selenoxides to allyl alcohols or addition of osmium(VIII) species on C=C double bonds) to one side, allows the transformation of methyl geranyl selenides to linalool and of methyl citronellyl selenoxide to 6,7-dihydroxy citronellyl selenide.