513 research outputs found

    Heat transfer in drop-laden turbulence

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    Heat transfer by large deformable drops in a turbulent flow is a complex and rich-in-physics system, in which drop deformation, breakage and coalescence influence the transport of heat. We study this problem by coupling direct numerical simulation (DNS) of turbulence with a phase-field method for the interface description. Simulations are run at fixed-shear Reynolds and Weber numbers. To evaluate the influence of microscopic flow properties, like momentum/thermal diffusivity, on macroscopic flow properties, like mean temperature or heat transfer rates, we consider four different values of the Prandtl number, which is the momentum to thermal diffusivity ratio:, and. The drop volume fraction is for all cases. Drops are initially warmer than the turbulent carrier fluid and release heat at different rates depending on the value of, but also on their size and on their own dynamics (topology, breakage, drop-drop interaction). Computing the time behaviour of the drops and carrier fluid average temperatures, we clearly show that an increase of slows down the heat transfer process. We explain our results by a simplified phenomenological model: we show that the time behaviour of the drop average temperature is self-similar, and a universal behaviour can be found upon rescaling by. Accordingly, the heat transfer coefficient (respectively its dimensionless counterpart, the Nusselt number) scales as (respectively) at the beginning of the simulation, and tends to (respectively) at later times. These different scalings can be explained via the boundary layer theory and are consistent with previous theoretical/numerical predictions

    Biowaste home composting: Experimental process monitoring and quality control

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    none5noBecause home composting is a prevention option in managing biowaste at local levels, the objective of the present study was to contribute to the knowledge of the process evolution and compost quality that can be expected and obtained, respectively, in this decentralized option. In this study, organized as the research portion of a provincial project on home composting in the territory of Pesaro-Urbino (Central Italy), four experimental composters were first initiated and temporally monitored. Second, two small sub-sets of selected provincial composters (directly operated by households involved in the project) underwent quality control on their compost products at two different temporal steps. The monitored experimental composters showed overall decreasing profiles versus composting time for moisture, organic carbon, and C/N, as well as overall increasing profiles for electrical conductivity and total nitrogen, which represented qualitative indications of progress in the process. Comparative evaluations of the monitored experimental composters also suggested some interactions in home composting, i.e., high C/N ratios limiting organic matter decomposition rates and final humification levels; high moisture contents restricting the internal temperature regime; nearly horizontal phosphorus and potassium evolutions contributing to limit the rates of increase in electrical conductivity; and prolonged biowaste additions contributing to limit the rate of decrease in moisture. The measures of parametric data variability in the two sub-sets of controlled provincial composters showed decreased variability in moisture, organic carbon, and C/N from the seventh to fifteenth month of home composting, as well as increased variability in electrical conductivity, total nitrogen, and humification rate, which could be considered compatible with the respective nature of decreasing and increasing parameters during composting. The modeled parametric kinetics in the monitored experimental composters, along with the evaluation of the parametric central tendencies in the sub-sets of controlled provincial composters, all indicate that 12–15 months is a suitable duration for the appropriate development of home composting in final and simultaneous compliance with typical reference limits.openFabio TATANO; Giacomo Pagliaro; Paolo Di Giovanni; Enrico Floriani; Filippo ManganiTatano, Fabio; Giacomo, Pagliaro; Paolo Di, Giovanni; Enrico, Floriani; Filippo, Mangan

    Emission of non CO2 greenhouse gases from landfills of different age located in central Italy

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    none5openM. MAIONE; J. ARDUINI; M. RINALDI; F. MANGANI; B. CAPACCIONIMaione, Michela; Arduini, Jgor; M., Rinaldi; Mangani, Filippo; B., Capaccion

    Adhesive restoration of endodontically treated premolars: influence of posts on cuspal deflection

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    To determine, by means of a non-destructive experimental procedure, the effectiveness of adhesive restorations in reducing the cuspal deflection of endodontically treated premolars, with or without root canal fiber posts.To determine, by means of a non-destructive experimental procedure, the effectiveness of adhesive restorations in reducing the cuspal deflection of endodontically treated premolars, with or without root canal fiber posts. MATERIALS AND METHODS: The cuspal deflection of ten sound, intact maxillary premolars was evaluated. A loading device induced deformation by axial force (ranging from 98 to 294 N) applied on the occlusal surface of teeth while laser sensors registered the amount of deflection. Once tested, teeth were endodontically treated and the marginal ridges were removed. The teeth were randomly divided into two groups and restored with: group 1) dual curing adhesive, flowable composite, and microhybrid composite; group 2) the same materials associated with root canal glass fiber post and composite cement. The cuspal deflection test was repeated with the same protocol after restorative procedures, allowing a direct comparison of the same samples. Statistical analysis was performed using ANOVA at a significance level of 0.05. RESULTS: Different average cuspal deflection was detected in the two groups: composite resin with post insertion resulted in lower deformation compared with composite alone. Mean deflection ranged from 3.43 to 12.17 ÎĽm in intact teeth, from 14.42 to 26.93 ÎĽm in group 1, and from 15.35 to 20.39 ÎĽm in group 2. ANOVA found significant differences (p = 0.02). CONCLUSION: Bonded composite restorations with fiber posts may be more effective than composite alone in reducing the cuspal deflection in endodontically treated premolars in which the marginal ridges have been lost

    Report on the activity of the GILDA-CRG beamline 2009-2013

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    Index Technical description of the beamline..................................................................................................3 Introduction ....................................................................................................................................3 Optics..............................................................................................................................................3 The XAS end station........................................................................................................................6 Standard data collection setup.....................................................................................................6 Surface XAS apparata.................................................................................................................8 Recent sample environment and Instrumentation developments................................................9 The x-ray diffraction (XRD) end-station.......................................................................................13 Beamline control...........................................................................................................................14 Administrative aspects........................................................................................................................16 Organisation..................................................................................................................................16 Beamline Staff Situation................................................................................................................17 Statistical data on Users and scientific production.............................................................................21 Future perspectives and plans for upgrade.........................................................................................25 Aim of the project.........................................................................................................................25 Design...........................................................................................................................................26 Timetable......................................................................................................................................31 Overview of the overall scientific activity.........................................................................................33 Selection of five publications........................................................................................................33 Highlights of the scientific activity................................................................................................34 Local order in semiconductors..................................................................................................34 Nanotechnology.......................................................................................................................44 Cements and porous systems....................................................................................................48 Chemistry.................................................................................................................................56 Earth Science............................................................................................................................61 Environment.............................................................................................................................67 Cultural Heritage.......................................................................................................................72 Health, medicine and life science .............................................................................................77 Acknowledgements...........................................................................................................................84 References.........................................................................................................................................85 Generic References.......................................................................................................................85 GILDA 2009-2013 Publications....................................................................................................8

    ANALISIS KEPUTUSAN PEMBELIAN DI TOKOPEDIA YANG DIPENGARUHI CELEBRITY ENDORSER, BRAND IMAGE, KELOMPOK REFERENSI DAN USIA

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    With higher dynamics of lifr makes people want everything quick and instant. It resulted with companies now starting to do e-commerce. The purpose of this research are to find out (1) celebrity endorser influence on purchasing decision in Tokopedia (2) brand image influence on purchasing decision in Tokopedia (3) reference group influence on purchasing decision in Tokopedia (4) age influence on purchasing decision in Tokopedia (5) celebrity endorser, brand image, reference group and age influences on purchasing decision in Tokopedia. Data were analyzed using Logistic Regression. The results of this research are (1) there is no significance influence between celebrity endorser and purchasing decision in Tokopedia. This is indicated by significant value 0.588 greater than 0.05 (2) ) there is significance influence between brand image and purchasing decision in Tokopedia. This is indicated by significant value 0.003 smaller than 0.05 (3) there is significance influence between reference group and purchasing decision in Tokopedia. This is indicated by significant value 0.000 smaller than 0.05 (4) there is no significance influence between age and purchasing decision in Tokopedia. This is indicated by significant value 0.186 greater than 0.05 (5) celebrity endorser, brand image, reference group and age together affect on purchasing decision in Tokopedia of 71.2

    ANALISIS KEPUTUSAN PEMBELIAN DI TOKOPEDIA YANG DIPENGARUHI CELEBRITY ENDORSER, BRAND IMAGE, KELOMPOK REFERENSI DAN USIA

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    With higher dynamics of lifr makes people want everything quick and instant. It resulted with companies now starting to do e-commerce. The purpose of this research are to find out (1) celebrity endorser influence on purchasing decision in Tokopedia (2) brand image influence on purchasing decision in Tokopedia (3) reference group influence on purchasing decision in Tokopedia (4) age influence on purchasing decision in Tokopedia (5) celebrity endorser, brand image, reference group and age influences on purchasing decision in Tokopedia. Data were analyzed using Logistic Regression. The results of this research are (1) there is no significance influence between celebrity endorser and purchasing decision in Tokopedia. This is indicated by significant value 0.588 greater than 0.05 (2) ) there is significance influence between brand image and purchasing decision in Tokopedia. This is indicated by significant value 0.003 smaller than 0.05 (3) there is significance influence between reference group and purchasing decision in Tokopedia. This is indicated by significant value 0.000 smaller than 0.05 (4) there is no significance influence between age and purchasing decision in Tokopedia. This is indicated by significant value 0.186 greater than 0.05 (5) celebrity endorser, brand image, reference group and age together affect on purchasing decision in Tokopedia of 71.2

    Repurposing the trypanosomatidic gsk kinetobox for the inhibition of parasitic pteridine and dihydrofolate reductases

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    Three open-source anti-kinetoplastid chemical boxes derived from a whole-cell phenotypic screening by GlaxoSmithKline (Tres Cantos Anti-Kinetoplastid Screening, TCAKS) were exploited for the discovery of a novel core structure inspiring new treatments of parasitic diseases targeting the trypansosmatidic pteridine reductase 1 (PTR1) and dihydrofolate reductase (DHFR) enzymes. In total, 592 compounds were tested through medium-throughput screening assays. A subset of 14 compounds successfully inhibited the enzyme activity in the low micromolar range of at least one of the enzymes from both Trypanosoma brucei and Lesihmania major parasites (pan-inhibitors), or from both PTR1 and DHFR-TS of the same parasite (dual inhibitors). Molecular docking studies of the protein–ligand interaction focused on new scaffolds not reproducing the well-known antifolate core clearly explaining the experimental data. TCMDC-143249, classified as a benzenesulfonamide derivative by the QikProp descriptor tool, showed selective inhibition of PTR1 and growth inhibition of the kinetoplastid parasites in the 5 µM range. In our work, we enlarged the biological profile of the GSK Kinetobox and identified new core structures inhibiting selectively PTR1, effective against the kinetoplastid infectious protozoans. In perspective, we foresee the development of selective PTR1 and DHFR inhibitors for studies of drug combinations
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