A procedure for computing the spot production rate in transitional boundary layers

The present work describes a method for the computation of the nucleation rate of turbulent spots in transitional boundary layers from particle image velocimetry (PIV) measurements. Different detection functions for turbulent events recognition were first tested and validated using data from direct numerical simulation, and this latter describes a flat-plate boundary layer under zero pressure gradient. The comparison with a previously defined function adopted in the literature, which is based on the local spanwise wall-shear stress, clearly highlights the possibility of accurately predicting the statistical evolution of transition even when the near-wall velocity field is not directly available from the measurements. The present procedure was systematically applied to PIV data collected in a wall-parallel measuring plane located inside a flat plate boundary layer evolving under variable Reynolds number, adverse pressure gradient (APG) and free-stream turbulence. The results presented in this work show that the present method allows capturing the statistical response of the transition process to the modification of the inlet flow conditions. The location of the maximum spot nucleation is shown to move upstream when increasing all the main flow parameters. Additionally, the transition region becomes shorter for higher Re and APG, whereas the turbulence level variation gives the opposite trend. The effects of the main flow parameters on the coefficients defining the analytic distribution of the nucleation rate and their link to the momentum thickness Reynolds number at the point of transition are discussed in the paper.[GRAPHICS]

Liquid baits with Oenococcus oeni increase captures of Drosophila suzukii

The spotted-wing drosophila (SWD), Drosophila suzukii Matsumura (Diptera: Drosophilidae), native to Eastern Asia, is an invasive alien species in Europe and the Americas, where it is a severe pest of horticultural crops, including soft fruits and wine grapes. The conventional approach to controlling infestations of SWD involves the use of insecticides, but the frequency of application for population management is undesirable. Consequently, alternative strategies are urgently needed. Effective and improved trapping is important as an early risk detection tool. This study aimed to improve Droskidrink® (DD), a commercially available attractant for SWD. We focused on the chemical and behavioral effects of adding the bacterium Oenococcus oeni (Garvie) to DD and used a new trap design to enhance the effects of attractive lures. We demonstrate that microbial volatile compounds produced by O. oeni are responsible for the increase in the attractiveness of the bait and could be later utilized for the development of a better trapping system. Our results showed that the attractiveness of DD was increased up to two-fold by the addition of commercially available O. oeni when combined with an innovative trap design. The new trap-bait combination increased the number of male and especially female catches at low population densitie

Megatrends and Trends Shaping Supply Chain Innovation

Companies operate in a macro-environment that is changing considerably due to large, transformative global forces namely megatrends and trends. The wave of these megatrends and trends generates new prospects as well as challenges for the future of supply chains. This chapter provides a review of 23 major megatrends and 72 trends identified in multiple dimensions along Political, Economic, Social, Technological, Legal, and Environmental (PESTLE) dimensions. The results are based on a systematic literature review and an experts’ workshop, and can be used to generate future supply chain scenarios

La conservazione preventiva del patrimonio librario come possibile alternativa al restauro tradizionale

The present paper focuses on the close relation between library collections and their preservation environment, aiming, in particular, at highlighting the importance of promoting and sustaining the monitoring. The paper proposes some simple and ready-to-use technologies – smart monitoring – to prevent future damages

Mechanochemical synthesis of PbTiO3 from PbO and TiO2

Data on mechanochemical synthesis of PbTiO3 from PbO and TiO2 without subsequent heating of activated mixtures are presented. Physical and chemical processes occurring during mechanical activation are followed by the X-ray diffraction (XRD) method, scanning electron microscope (SEM) analysis and measurement of BET specific surface area. It was shown that during vibro milling of 10 g oxide mixture, formation of PbTiO3 was ended after 60 min. The progression of the chemical reaction was detected by the XRD method and chemical analysis. (C) 1998 Elsevier Science S.A. All rights reserved

Mechanochemical synthesis of PbTiO3 from PbO and TiO2

Data on mechanochemical synthesis of PbTiO3 from PbO and TiO2 without subsequent heating of activated mixtures are presented. Physical and chemical processes occurring during mechanical activation are followed by the X-ray diffraction (XRD) method, scanning electron microscope (SEM) analysis and measurement of BET specific surface area. It was shown that during vibro milling of 10 g oxide mixture, formation of PbTiO3 was ended after 60 min. The progression of the chemical reaction was detected by the XRD method and chemical analysis. (C) 1998 Elsevier Science S.A. All rights reserved