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Background: The ubiquitous Lewis acid/base interactions are important in solution processes. Analytical chemistry may benefit from a better understanding of the role of Lewis basicity at the molecular level or acting through a bulk solvent effect. Objective: To delineate (i) the basicity at a molecular level, hereafter referred to as solute basicity, and (ii) the solvent basicity, which is a bulk-liquid property. Methods: The literature that relates Lewis basicity scales and solvent effects is analyzed. A special focus is placed on two extensive scales, the Donor Number, DN, and the BF3 Affinity scale, BF3A, which were obtained by calorimetric measurements on molecules as solutes diluted in a quasi-inert solvent, and therefore define a molecular Lewis basicity. We discuss the validity of these solute scales when regarded as solvent scales, in particular when the basicity of strongly associated liquids is concerned. Results: We demonstrate the drawbacks of confusing the Lewis basicity of a solvent molecule, isolated as a solute, and that of the bulk liquid solvent itself. Conclusion: Consequently, we recommend a reasoned use of the concept of Lewis basicity taking clearly into account the specificity of the process for which a Lewis basicity effect may be invoked. In particular, the action of the Lewis base, either as an isolated entity or as a bulk liquid, must be distinguished.

Background: The vehicle fuel injector directly affects the power performance, emission characteristics and economic efficiency of the engine. At present, several testing standards are stipulated on accurate measurement of the working characteristics of fuel injectors. Objective: The purpose of this study is to provide an efficient patent about the method and system for testing the working characteristics of a vehicle fuel injector. Methods: Two key techniques are significant to establish a standard test environment. The patent about the pressure control approach and the injector driving method was proposed. The adaptive fuzzy PID approach was applied to control pressure. An adaptive multi-functional driver was designed and developed for both the voltage-driven and current-driven port fuel injectors. Results: The experiments on the two key technologies were conducted. During the dynamic flow test, the settling time using the system was 1ms. For the static flow test, the settling time was 1 s. The maximum changing rate of pressure fluctuation was 1%. Then, the system was verified by test on the flow characteristics and dynamic response of the voltage-driven and current-driven injectors. The linear deviation of each dynamic flow curve was between ± 3% to ± 6%. Furthermore, the deviation of the dynamic flow curves from the repeated test was small. The maximum deviation of the static flow results was less than 4% and the dynamic response of the injector varied with the change of the pressure. Conclusion: The system meets the requirements of the related standards. The experimental results prove that the system is stable and reliable.

Background: In the present situation where there is a water shortage globally, nanoparticles can play a vital role in treating wastewater to make it usable for several processes. Industrial wastewater contains numerous heavy metals and associated wastes that enter our food chain by one means or other. This article provides a review of applications of nanoparticles in wastewater treatment and highlights the significance of photocatalytic nanoparticles in general. Methods: Online journals and books related to wastewater treatment using nanoparticles are reviewed to compile their essentials findings. General mechanisms, applications, limitations, and comparison of photocatalytic nanoparticles are reviewed as well. Results: A study of photocatalytic nanoparticles shows that TiO2 and ZnO nanoparticles have excellent photocatalytic capabilities as compared to other nanoparticles due to their bandgap properties; however, the usage of these nanoparticles is limited since there is higher recombination rate of electrons and holes in photocatalysis. Further, individual limitations also exist as TiO2 is inoperable in the visible light region. So, their heterostructures with other nanoparticles have been developed to overcome their limitations. Other nanoparticles, like noble metals, and those like CuO, CeO2, SnO2 have potential in carrying out photocatalytic degradation of contaminants of wastewaters. Conclusion: Several contaminants can be eliminated from wastewater bodies using photocatalytic nanoparticles. The efficiency of photocatalytic nanoparticles can be enhanced by coupling them with suitable species. Research in this area can prevent the water shortage of upcoming years.

Au sein de l'Idrrim, le groupe spécialisé EAPIC (Essais d'aptitude par intercomparaison) organise des essais d'aptitude par comparaison interlaboratoires dans le domaine routier. La série 8.2.17, réalisée en 2017-2018 sur le module des enrobés, a fourni des données en grand nombre sur de nombreux paramètres pouvant influer sur les résultats d'essais. L'article fournit les principaux enseignements tirés de leur analyse.

Le guide « bruit de roulement » est un ouvrage collectif rédigé par le Groupe National Caractéristiques de Surface (GNCDS), groupe de travail spécialisé de l'IDRRIM. Destiné aux acteurs de la construction routière, il constitue une aide à la prescription de revêtements acoustiques et la prise en compte du bruit dans la gestion d'un réseau routier. Il rappelle les connaissances fondamentales sur l'émission et la propagation du bruit de roulement, les règlementations en cours et modèles de prévision, les méthodes de mesure et propose des outils et recommandations pour la prise en compte du bruit par la maîtrise d'ouvrage. En cours de validation, il devrait être publié prochainement.