Impact of the surface characteristics of rainwater tank material on biofilm development

In order to determine the impact of rainwater construction material on the development of a biofilm, three materials were tested: concrete, clay, and PVC. The biofilm attachment was initially more effective on clay coupons, but, after a period of three days, concrete coupons produced a greater quantity of biofilm than clay and PVC, in that order. The heterotrophic plate count in the rainwater indicated that this quantity tended to first increase following a rainfall, and then decrease. The new materials seemed to attach themselves to the existing biofilm on the wall and/or sediment in the form of small particles. The presence of fecal coliforms in the biofilm coupons was noted after major rainfall events, and this was correlated with the increase in fecal coliforms in the water. This study concluded that the most favorable support for biofilm development is concrete, clay, and PVC, in that order.     

Overview of the local production process of raw milk butter in Wallonia (Belgium)

This study aims to describe the procedures and practices used in local production of raw milk butter. The demand for local products is increasing; hence, there is a need to describe the practices used in the artisanal production of raw milk butter. Therefore, a survey of 147 raw milk butter producers was carried out. The results from the survey indicate that there is not one single way to produce butter at artisanal level. In terms of maturation, six temperature sequences were distinguished. Attention is required at every step of production starting from breeding.     

基建仓库

基建仓库项目位于莱瓦顿的Harlingervaart运河岸边,作为周边建筑的仓库,它具有独特的趣味性良好的形体感,因此被认为是立于运河沿岸广场上的一座雕塑。建筑的入口处挑出悬臂,并且顺势突出建筑南侧的体量     

Electroless ultrasonic functionalization of diamond nanoparticles using aryl diazonium salts

We report a novel and very handful strategy for the functionalization of diamond nanoparticles (NDs), based on the ultrasound-assisted grafting of aryl groups from the electroless reduction of diazonium salts. For this study, 4-nitrobenzenediazonium salt was used as a model molecule and the reaction was investigated in neutral and acidic aqueous media. Spectroscopic evidence for the successful attachment of aryl groups to nanodiamonds (NDs) was given by IR and XPS which clearly detect characteristic NO₂ peaks. Moreover, the absence of any peaks from the ⁺N≡N group in the IR spectra is a clear indication of the chemical reduction of the parent diazonium salt at the surface of NDs. This spontaneous chemical modification of NDs by aryl diazonium salts was confined to the surface of the ND particles; indeed, XRD measurements have shown that the crystalline structure of the bulk of the particles was unaffected. It opens up new possibilities towards the control of the surface chemical composition of NDs using simple protocols operated in very soft conditions, i.e. in water at room temperature. It shows conclusively that the chemistry toolbox of experts interested in nanodiamonds should contain aryl diazonium salts, given their versatility in forming active platforms.     

Comparing Al-SBA-15 Support and Pt/Al-SBA-15 Catalyst: Changes in Al Speciation and Acidic Properties Induced by the Introduction of Pt via Aqueous Medium

Differences between the acidic properties of silicoaluminic Pt-containing catalysts and those assessed on their parent supports have been reported in the literature and attributed to the presence of the metal nanoparticles and to their influence on the acid sites. It is shown here that for mesoporous materials containing various types of Al species, an alternative explanation can be proposed. ²⁷Al NMR spectroscopy, FTIR of adsorbed CO and probe catalytic tests suggest the redistribution of aluminium atoms upon contact of the parent support with the aqueous solution containing the Pt precursor. Upon contact with water and thermal treatment, strong and mild Brønsted sites (Si–O(H)–Al) transform into strong Lewis sites (isolated tetracoordinated Al atoms). As a consequence, it may not be straightforward to deduce the acidic properties of metal-containing catalysts supported on Al-containing mesoporous materials from those of the bare support, because the surface species may differ significantly.     

THz Photoconductive Antennas Made From Ion-Bombarded Semiconductors

We review the most important developments in the technology of THz photoconductive antennas made from ion-bombarded semiconductors. We describe the structural, optical and electrical properties of various ion-bombarded semiconductors and discuss the nature of the defects introduced by the ion bombardment technique and their impact on the characteristics of THz photoconductive antennas. Finally, we present the performances achieved by photoconductive antennas based on ion-bombarded semiconductors for optical excitation at various wavelength.     

Theoretical Modelling of Film-Forming Mechanisms Under Transient Conditions: Application to Deceleration and Experimental Validation

This paper proposes an analytical model for line (1D) and point contacts (2D), based upon the Ertel’s hypothesis to predict the evolution of film thickness in steady-state and transient conditions in elastohydrodynamic lubrication. This theoretical approach, applied to a velocity ramp at constant deceleration, is perfectly supported by experimental results in terms of film thickness distribution during the deceleration process and in terms of central film thickness at the vanishing of the entrainment velocity. This work emphasizes the role of the transport effects of the lubricant at the instantaneous entrainment velocity on the time and length scales at which the film thickness disturbances induced by the deceleration process occur until the complete halting of the surfaces.     

Context-sensitive decision support systems in road safety

Enterprises often embed decision-making processes in procedures in order to address issues in all cases. However, procedures often lead to sub-optimal solutions for any specific decision. As a consequence, each actor develops the practice of addressing decision making in a specific context. Actors contextualize decision making when enterprises are obliged to decontextualize decision making to limit the number of procedures and cover whole classes of decision-making processes by generalization. Practice modeling is not easy because there are as many practices as contexts of occurrence. This chapter proposes a way to deal effectively with practices. Based on a conceptual framework for dealing with context, we present a context-based representation formalism for modeling decision making and its realization by actors. This formalism is called contextual graphs and is discussed using the example of modeling car drivers’ behaviors. This article is part of the “Handbook on Decision Support Systems” edited by Frada Burstein and Clyde W. Holsapple (2008) Springer.