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Main Influence (main + influence)
Selected AbstractsOrganic Phase PPO Biosensors Prepared by Multilayer Deposition of Enzyme and Alginate Through Avidin-Biotin InteractionsELECTROANALYSIS, Issue 24 2004S. Cosnier Abstract Films of electrogenerated polypyrrole and hydrophilic alginate, both functionalized with biotin moieties, were used to allow for the transfer of polyphenol oxidase activity in organic media. Enzyme electrodes, based on multilayered structures, were protected at the molecular level by the affinity binding of alginate as a hydrophilic additive, and were then transferred into chlorobenzene, dichloromethane, chloroform, ethyl acetate or acetonitrile. The biosensor performance for the detection of catechol at ,0.2,V was investigated, highlighting the main influence of the hydrophobicity of the solvent and, to a lesser extent, the dielectric constant. The effect of the substrate hydrophobicity on the biosensor response was examined in chlorobenzene. [source] Geology and the London UndergroundGEOLOGY TODAY, Issue 1 2009Jonathan D. Paul Geology as a whole is the main influence on determining the feasibility of tunnelling for underground railways, and at what cost. Favourable conditions encouraged the early development of a network, significantly alter the methods used for construction, and are what form the tunnels, in terms of horizontal and vertical alignment. Local geology is shown, by means of two cross-sections following the tunnels, to be more important than the overall regional geology, where the underlying strata exhibit pronounced variations in permeability, and so mechanical properties. Geological complexities specific to the area of tunnelling generate problems during construction, but lead to technological innovation in the long term and a better understanding of local stratigraphy. As the result of this, and the increase in the quality of preliminary surveys, we are increasingly able to tunnel in areas previously considered treacherous. [source] Morphology in Immiscible Polymer Blends During Solidification of an Amorphous Dispersed Phase under ShearingTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 6 2002Yves Deyrail Abstract Solidification under shear of dispersed polycarbonate (PC) fibers in copolymer polyethylene-methyl acrylate matrix (EMA) was investigated using a hot optical shear device. First, the deformation of PC droplets and its modeling under isothermal conditions were studied for comprehension purposes. Overall agreement with literature models was found and the main influence of the viscosity ratio has been stressed. Second, the morphology control through dynamic quenching was experimented. It consists of solidifying the amorphous PC dispersed phase under shear flow. Break-up times of PC fibers were taken into account. Shear rate and quenching-time balance was demonstrated. Thus, during dynamic solidification, a fibrillar morphology could be obtained through rapid quenching. Long quenching times allow nodular morphology, whose size depends on the shear rate used. PC rods can be obtained by adjusting the shear rate during dynamic quenching. La solidification sous cisaillement du polycarbonate (PC) dispersé dans une matrice copolymère éthylène-acétate de vinyle (EMA) a été suivie à l'aide d'un microscope et d'une platine de cisaillement chauffante. Dans un premier temps la déformation isotherme de billes de PC pour différentes températures a été étudiée, ainsi que sa modélisation. Une bonne corrélation avec les modèles issus de la littérature a été obtenue. L'importance du rapport des viscosités a été ainsi soulignée. Dans un second temps le contrôle de la morphologie par le procédé de « refroidissement dynamique » a été expérimenté. Celui-ci consiste à solidifier le PC sous cisaillement pendant le refroidissement. Les temps de rupture des fibres de PC ont été considérés et l'importance du couple gradient de cisaillement-temps de refroidissement sur le contrôle de la morphologie a été mis en évidence. Pendant la solidification, un refroidissement rapide permet d'obtenir une morphologie fibrillaire. [source] Investigation of the Influence of Volute Design on Journal Bearing Bias Force Using Computational Fluid DynamicsARTIFICIAL ORGANS, Issue 9 2010Roland Graefe Abstract Hydrodynamic fluid film bearings represent an optimal possibility for rotary blood pump (RBP) miniaturization and wear-free operation. Size is a key parameter in the development of ventricular assist devices (VADs) as smaller patients and the pediatric population become eligible for the device. In order to maintain rotor suspension, radial journal bearings have been widely used in industrial applications as well as in some VADs. A main influence on the performance of such a bearing is the applied hydraulic bias force. This study combines numerical and analytical approaches to determine the bias force of different impeller-volute configurations and the resulting eccentricity for the hydraulic design point and also for off-design operation. Significant differences occur for different impeller-volute configurations, with the circular volute displaying the most beneficial properties for a stable impeller suspension. Moreover, an analytical prediction of eccentricity was found to be incorrect for the relatively small forces that occur in RBPs. [source] Kinetics and mechanisms of solvolysis of 3-chloro-3-ethylpentane in alcohols as solvents.JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 3 2001Application of multiparametric equations, factor analysis to the solvolytic reactions of tert -alkyl halides Abstract This paper introduces a new set of rate constants for solvolysis of 3-chloro-3-ethylpentane in eight monoalcohols, from methanol to 2-methylbutan-1-ol, and in 10 dialcohols, from ethane-1,2-diol to pentane-1,5-diol, and also in diethylene and triethylene glycol. These results together with previous obtained data for several solvolytic reactions of tert -alkyl halides (2-iodo-2-methylpropane, 2-bromo-2-methylpropane, 2-chloro-2-methylpropane, 2-bromo-2-methylbutane, 2-chloro-2-methylbutane and 3-chloro-3-methylpentane) in the same mono- and dialcohols were studied by means of a standard multiparametric approach and by target factor analysis (TFA). TFA provides an open criterion for selecting the quantity and nature of the possible causes of the variation in the rate constants. The results allow one to identify and quantify the dominant solute,solvent interaction mechanisms affecting the reactions. Solvent dipolarity, polarizability and hydrogen bond donor acidity are the main influences on reactivity, although mono- and dialcohols behave differently. Copyright © 2001 John Wiley & Sons, Ltd. [source] A survey of influences on the practice of psychotherapists and clinical psychologists in training in the UKCLINICAL PSYCHOLOGY AND PSYCHOTHERAPY (AN INTERNATIONAL JOURNAL OF THEORY & PRACTICE), Issue 2 2006Mike P. Lucock A questionnaire survey of 95 qualified psychotherapists of various therapeutic orientations and 69 psychologists in clinical training was carried out to investigate the main influences on their clinical practice, using the Questionnaire of Influencing Factors on Clinical Practice in Psychotherapies (QuIF-CliPP). For the qualified group the most highly rated factors were current supervision, client characteristics, client feedback, psychological formulation, intuition/judgement, professional training and post-qualification training. For the trainees, those rated highest were current supervision, past supervision, client characteristics, client feedback, psychological formulation and professional training. Evidence based factors such as treatment manuals and evidence based guidelines were rated relatively low for both groups, although the cognitive behaviour therapists rated them significantly higher than the other groups. Personal therapy was rated highly by the psychodynamic, psychoanalytic, person centred and eclectic therapists but not by CB therapists. The implications of these findings for the application of evidence based practice and the need to evaluated supervision, personal therapy and training are discussed.,Copyright © 2006 John Wiley & Sons, Ltd. [source] | ||||||||||