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Destruction Process (destruction + process)
Selected AbstractsFunnel-and-Gate Performance in a Moderately Heterogeneous Flow DomainGROUND WATER MONITORING & REMEDIATION, Issue 3 2001Lacrecia C. Bilbrey The funnel-and-gate ground water remediation technology (Starr and Cherry 1994) has received increased attention and application as an in situ alternative to the typical pump-and-treat system. Understanding the effects of heterogeneity on system performance can mean the difference between a successful remediation project and one that fails to meet its cleanup goals. In an attempt to characterize and quantify the effects of heterogeneity on funnel-and-gate system performance, a numerical modeling study of 15 simulated heterogeneous flow domains was conducted. Each realization was tested to determine if the predicted capture width met the capture width expected for a homogeneous flow domain with the same hulk properties. This study revealed that the capture width of the funnel-and-gate system varied significantly with the level of heterogeneity of the aquifer. Two possible remedies were investigated for bringing systems with less than acceptable capture widths to acceptable levels of performance. First, it was determined that enlarging the funnel and gate via a factor of safety applied to the design capture width could compensate for the capture width variation in the heterogeneous flow domains. In addition, it was shown that the use of a pumping well downstream of the funnel and gate could compensate for the effects of aquifer heterogeneity on the funnel-and-gate capture width. However, if a pumping well is placed downstream of the funnel and gate to control the hydraulic gradient through the gate, consideration should be given to the gate residence time in relation to the geochemistry of the contaminant removal or destruction process in the gate. [source] Assessment of naphthalene biodegradation efficiency of Pseudomonas and Burkholderia strains tested in soil model systems,JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 2 2006Andrei E Filonov Abstract The kinetic parameters of the naphthalene degradation process performed by indigenous and introduced microorganisms were studied in soil model systems. The introduction of active naphthalene-degrading strains Pseudomonas putida BS3701 and G7 in soil model systems accelerated the naphthalene destruction process by a factor of three to four. Moreover, the addition of salicylate (0.1 mg g,1 dry soil) to the systems containing the introduced microbial strains again doubled the rate of the naphthalene degradation process. To provide a quantitative assessment of the naphthalene biodegradation process, a mathematical model describing the bacterial growth, the consumption of the naphthalene, the production and subsequent consumption of naphthalene cleavage products, and the consumption of organic soil substances in soil model systems was developed. An approach for assessment of the degradation efficiency of low solubility polycyclic aromatic hydrocarbon provided by bacteria of genera Pseudomonas and Burkholderia in soil was suggested. The approach will enable comparison and selection of the most active degraders, which have the potential for application in biotechnologies for cleaning of soils contaminated by polycyclic aromatic hydrocarbons. Copyright © 2005 Society of Chemical Industry [source] A Raman spectroscopic and combined analytical approach to the restoration of severely damaged frescoes: the Palomino projectJOURNAL OF RAMAN SPECTROSCOPY, Issue 4 2008Howell G. M. Edwards Abstract The deterioration of art objects is normally relatively minor, controllable and attributable to environmental changes or bacterial invasion, and until now there has not been any recorded attempt to analyse an artwork that has been deliberately and significantly destroyed. The analytical problems are correspondingly larger but the potential reward from any information that can be forthcoming is thereby proportionately greater. The 17th Century Palomino frescoes on the vaulted ceiling of the Church of Sant Joan del Mercat in Valencia were largely destroyed by insurgents in the Spanish Civil War in 1936. The ensuing gunfire and a series of seven conflagrations inside the church had a devastating effect upon the artwork, and the surviving areas were also rendered unstable with respect to their detachment from the substrate. During the current restoration project being undertaken on these frescoes, an opportunity was provided for the application of several analytical techniques to secure information about the original pigment palette employed, the technology of application used by Palomino and the changes consequent upon the destruction process. Here, we report for the first time the use of analytical Raman spectroscopy, supported by scanning electron microscopy (SEM) and voltammetry of microparticles, for the combined identification of pigments, binders, substrate treatments and pigment alteration in an important, although badly damaged, wall painting for the informing of the ongoing conservation and restoration strategy. Copyright © 2008 John Wiley & Sons, Ltd. [source] From massacre to the genocidal processINTERNATIONAL SOCIAL SCIENCE JOURNAL, Issue 174 2002Jacques Sémelin Since the time of Raphael Lemkin's work, genocide studies have been conducted primarily at the intersection of law and social science. As a result, the term ,genocide' has frequently been employed in a normative sense, leading to considerable conceptual difficulties and debate. How can such problems be overcome? This article comes down firmly in favour of moving away from a legal approach to genocide studies. It recommends the use of non-normative vocabulary based on the concept of ,massacre', this term being suggested as a reference lexical unit. It also puts forward the more general expression ,destruction process', whose most dramatic form is massacre. Massacre is not an act of actual ,madness' but the response to what the author calls ,delusional rationality'. In that respect, he distinguishes between two destruction strategies: one aimed at a group's subjugation and the other at its eradication. It is in the latter case that one can refer to a genocidal process. This article thus considers that genocide should not be defined as a static concept but viewed rather as a particular dynamic of civilian destruction, being the product of both its perpetrators' will and of favourable circumstances. [source] Optical absorption, paramagnetic resonance and depolarisation currents in MgAl2O4 spinelPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 3 2007Roberto Paiva Abstract Optical Absorption (OA), Electron Paramagnetic Resonance (EPR) and Thermally Stimulated Depolarisation Currents (TSDC) techniques were applied to study the effects of irradiation and thermal treatments in the formation, aggregation and destruction processes of dipole defects in MgAl2O4 spinel. Irradiated MgAl2O4 crystals present two OA bands centred at 3.4 eV and 5.1 eV. The 3.4 eV band increases with the irradiation-dose, stabilizes its maximum height for doses near 10 kGy and is completely destroyed for thermal treatments above 500 K. This same band decays when the sample is maintained at room temperature reaching a constant value after a few weeks. The EPR spectrum is composed by two superimposed bands at g = 2.011. The gamma dose dependence, the thermal treatments between 370 K and 500 K and the thermal decay of the two bands at room temperature, show that each band behaves in a different way thus indicating that they are associated with two different defects. Gamma dose of 10 kGy produces a TSDC band at 245 K. When the sample is maintained at room temperature, after the gamma irradiation, for several weeks, a displacement in the peak position to 290 K, is observed. Thermal treatments above 500 K destroy the 290 K band. This band is associated to at least two V-type centres. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Influence of lipopolysaccharide and interleukin-6 on RANKL and OPG expression and release in human periodontal ligament cellsAPMIS, Issue 10 2009ANNA C. KRAJEWSKI Recent research into periodontal disease pathology focuses on the role of receptor activator of nuclear factor-,B ligand (RANKL) and osteoprotegerin (OPG) in periodontal bone destruction processes. RANKL regulates the differentiation of osteoclast by binding to its specific receptor RANK, while OPG inhibits the differentiation of osteoclasts by binding RANKL and therefore preventing RANKL to bind RANK. The aim of the present study was to investigate the influence of Porphyromonas gingivalis lipopolysaccharide (LPS) and interleukin-6 (IL-6) on RANKL and OPG expression and release in periodontal ligament (PDL) cells. Human PDL cells were stimulated for 48 h with purified P. gingivalis LPS and IL-6. OPG and sRANKL release were assessed by using enzyme-linked immunosorbent assay technique. OPG and RANKL expression was quantitatively measured by using the real-time PCR technique. Whereas P. gingivalis LPS induced sRANKL release, expression was only slightly increased, IL-6 did not show an effect on RANKL expression or release. In conclusion the data demonstrate that stimulation of PDL cells with P. gingivalis LPS leads to an increased release of sRANKL, rather than increased RANKL expression. Through this action, P. gingivalis LPS may exert its biological effect on osteoclast formation and bone resorption. [source] | ||||||||||