Advanced Materials Research Vol. 324

Abstract: Iatrogenic infections due to contaminated medical devices are significant problem in the field of medicine, and have motivated the search for alternative surface disinfection/sterilization methods and technologies. During the last decade, a strong effort has been made in the field of non-thermal plasmas, including fundamental work from a physical, but also biological point of view. Non-thermal plasmas are used in industry for the modification of surface properties such as to improve wettability and adherence, and also for the deposition of thin films. The present work considers the treatment of surfaces contaminated by either bacteria or proteins with the effluent gas exiting from an atmospheric pressure dielectric barrier discharge. The discharge reactor consisted of a coaxial cylindrical geometry DBD reactor energized by a 30 kHz applied voltage. The effluent gas was used to treat surfaces contaminated with Escherichia coli (strain DH10B) or RNAse A (124 amino acids, 13.7kDa, known to be thermal-resistant). Results show that the decontamination of surfaces by the effluent gas from a humid argon DBD is effective, and that the effectiveness is greater the closer the biological samples are placed to the DBD source. The results also indicate that the mechanism of bacterial inactivation is based on a combination of stable oxidative species such as ozone and hydrogen peroxide as well as shorter lived species such as hydroxyl radical.

Abstract: Air pollution Particulate Matter (PM2.5) is described as one of the major risk factors affecting human health. Hence, the objective of our research project was to evaluate the lung toxicity of PM_2.5 collected in Dunkerque (France), through the study of the metabolic activation of its organic fraction (e.g. Polycyclic Aromatic Hydrocarbons, PAHs; Volatile Organic Compounds, VOCs) and its genotoxicity in two human cell models: embryonic lung epithelial L132 cells and Alveolar Macrophages (AM) isolated from bronchiolo-alveolar lavages of healthy outpatients, in mono- and/or coculture. The coculture system we used allowed the direct exposure of AM to PM_2.5, and the interaction between the two cell types only through soluble factor diffusion. Exposure to Dunkerque City’s PM_2.5 induced the gene expression of phase I and phase II enzymes (e.g. CYP1A1, CYP2E1, CYP2F1, NQO1, GST∏1, GSTμ3) involved in the metabolic activation of PAHS and/or VOCS, in AM, in mono- and coculture, and in L132 cells, only in monoculture. Taken together, these results reinforced the key role of AM in lung defenses, and indicated that particles, as physical vector of the penetration and retention of coated-PAHS and/or VOCS within cells, enabled them to exert a durable toxicity. DNA bulky adduct formation was also reported not only in Dunkerque City’s PM_2.5-exposed AM, in mono- and coculture, but also in L132 cells from PAH-exposed coculture. Loss of Heterozygosity (LOH) and/or MicroSatellite Instability (MSI) of some MicroSatellites (MS) located in multiple critical regions of chromosome 3 were reported in L132 cells from Dunkerque City’s PM_2.5-exposed mono- or cocultures.

Abstract: Atmospheric Total Suspended Particles (TSP) were sampled from 16 different points in a coastal industrial region in North Lebanon, between April and October 2008. The samples were analyzed for water soluble ions and metals concentrations using Ion Chromatography (I.C.) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The results showed possible natural contribution to aerosols through sea salt emissions (Na/Cl-/Mg), and crustal sources (K/Fe/Ti). However, ions such as NH4+, NO3-, and SO42- were attributed to secondary aerosols. Finally, the result of the enrichment factor analysis showed that vehicles’ emissions (Zn/Cu/Pb/Ni/V/Cr), quarries (Ca), and phosphate rocks impurities (Zn/Cd/Cu/Pb) were the most important anthropogenic contributions to the metal’s load in the aerosols.

Abstract: Current researches on the topic of indoor air pollution are moving towards expertise and prevention. Therefore it seems so critical to invest in the area of expertise and create a measuring device performing chemical, physical and bacteriological analysis in one click. Our choice of development towards this system of information management is oriented towards a modular system which can simultaneously transmit on real-time the analysis in the internet. Our production work has used several solutions and analyzed several possible methods such as microprocessor that has shown its reliability. The electronic system worked well even with some problems solved at the level of detection of particles α, β and δ. The solution NO-IP as for the transfer of data over the Internet has been successfully tested. In the same way we have been constrained to achieve measurement campaigns to verify the ability of the device to give consistent values. These campaigns were conducted on the Beaulieu of the University of Rennes 1, given the size of the site; it gives us a fairly comprehensive range of situations. These measurement campaigns extended for several months, with the purpose of comparing and analyzing the various results. These campaigns offer an opportunity of testing the operation of the aircraft and assessing the performance, knowing that all measures were compared to the device certified EN (Gasman). For the development of our device, we specify the direction and scope of the study area, analyze the existing level of detection performed and technical data manipulated, obtain a comprehensive description of the electronic system and reach a reasoned choice of a solution type of development. This allowed us to develop a multifunction prototype which objective is to control the quality of indoor air pollution in habitations. This device admits the same principle as product modem M2M (Machine to Machine). Through processes M2M, machinery (measuring instruments (device) and air handling system) is already able to communicate among them without human intervention. Given this new world of service, the management of environmental risks becomes more responsive.

Abstract: Sub-micrometric iron particles (Fe⁰) and amended Fe⁰ (Cu⁰Fe⁰) were tested for the aqueous removal of b-lactam antibiotics. Comparative batch experiments were performed separately on aqueous solutions of dicloxacillin (DCX), cloxacillin (CLX) and oxacillin (OXA). Three different initial concentrations (1, 5 and 10 mg L^-1) and four different iron loads (r = 10, 20, 40 and 53 g L^-1) were tested. Furthermore, two different mixing regimes were tested: (i) non-disturbed conditions, and (ii) vortex mixing. This experimental design enabled the confirmation of the crucial role of in-situ formed iron corrosion products (Fe oxides) on the removal process. The dynamic process of Fe oxides formation induces adsorption and enmeshment (sequestration or co-precipitation) of dissolved antibiotics. Results clearly delineated the superiority of Cu⁰Fe⁰ bimetallics compared to Fe⁰. For example, after 4 h of contact with iron particles at r = 40 g L^-1, OXA, CLX and DCX (10 mg L^-1 each) disappeared to an extent of 31, 46 and 71%. However, quantitative antibiotic removal (~90%) was noticed when Cu⁰Fe⁰ bimetallic was used at lesser load (r = 20 g L^-1) under vortex mixing. On the other hand, non-disturbed systems showed partial removal (~ 25%) of antibiotics over 7 h of reaction at r = 10 g L^-1 (Fe⁰) while almost complete removals were noticed for the Cu⁰Fe⁰ bimetallic system for the same metal load and period e.g. 75, 79 and 86% removal for OXA, CLX and DCX respectively.

Abstract: Exposure to air pollution Particulate Matter (PM) is one of the risk factors involved in the high incidence of respiratory and cardio-vascular diseases. In this work, to integrate inter-seasonal and inter-site variations, fine particle (PM_2.5) samples have been collected in spring-summer 2008) and autumn 2008-winter 2009, in Dunkerque (France) under urban or industrial influence, and in Rubrouck (France), under rural influence. Attention was paid to characterize their physico-chemical characteristics, and to determine their ability to induce oxidative stress and inflammatory response in a human bronchial epithelial cell model (BEAS-2B cell line). Physico-chemical characterization of the six PM samples showed their heterogeneities and complexities depending upon their respective natural and/or anthropogenic emission sources. Lung cytotoxicity of these air pollution PM_2.5 samples, as shown in BEAS-2B cells, might rely on the induction of oxidative stress conditions and particularly on the excessive inflammatory response.

Abstract: In this work, we study the microstructure of porous alumina Al₂O₃ through the acoustic signature behavior V(z). This function depends on the low porosity when annular lenses conditions at an operating frequency of 1 GHz are used. In non destructive control, this quantitative investigation which allows the determination of mechanical materials properties is of a great importance in the measurement of the surface waves attenuation in this type of biomaterials. Hence, we have numerically simulated the porous alumina acoustic signatures through variable occultation of generating rays at the lens center, in order to quantify the occultation limiting angle. Consequently, the evaluation of the equivalent Rayleigh velocity using the fast Fourier transform (F.F.T) spectra was achieved thanks to the suppression of the Rayleigh mode generation.

Abstract: The biosorption by cork powder is considered as a new method for heavy metal removal from industrial waste waters such as chromium tanning factories. The aim of this study is to evaluate the efficiency extent of this method using a cork powder as biosorbent for hexavalent chromium Cr(VI). The Fourier Transform Infrared spectroscopy (FTIR) analysis permits to distinguish the type of functional groups likely to participate in metal binding. A linear form of BET isotherms for all the three used temperatures (25, 35 and 45°C) and a pseudo-second-order Lagergren equation of adsorption kinetics are obtained. Other experimental results highlight the meaningful influence of parameters such as contact time, pH and concentrations of the solution, on chromium adsorption rate that reach a 97% value under definite conditions particularly a pH of 2-3 values.

Abstract: Glasses have been used as decorative objects in Thailand for several hundred years. Decorative glasses can generally be seen as architectural components in old styled palaces and Buddhist objects. There were various colors ranging from transparent to amber, blue, green and red with different shades among glass of different colors. Fragments of archaeological glass samples were characterized for the first time using Raman microscopy with the aim of obtaining information that would lead to identification of the glass samples by means of laser scattering. The samples were also investigated using other techniques, such as particle induced X-ray emission spectroscopy and scanning electron microscope operated with energy dispersive X-ray fluorescence spectrometer. They were mostly lead-silica based glasses. The colors resulted from metal ions. The difference in chemical composition was confirmed by Raman signature spectra.

Abstract: The Thai amulets that created in an image of Lord Buddha meditation were made to explain the Dharma of Buddha and believed to bless every life in this world for good karma. Phra Somdej Wat Rakhang amulet is the top of the five most famous Thai amulets. There are many molds with various compositions. In this work, it was the first time that X-ray fluorescence spectrometry methods; scanning electron microscope cooperated with energy dispersive X-ray fluorescence spectrometer (SEM/EDS) and particle induced X-ray emission spectroscopy (PIXE) were carried out to analyze their compositions. Two samples were collected from different molds. Results revealed C, Ca and Si were main composition. The differences in their compositions have been used to identify and characterize for each molds.