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Green Organic Reactions “on Water”
Published in Vera M. Kolb, Green Organic Chemistry and Its Interdisciplinary Applications, 2017
A new nomenclature that would make a distinction between in-water reactions of soluble versus insoluble reactants was needed. The new nomenclature introduces terms “on water,” “in water,” “water-promoted,” and “in the presence of water,” among others (Lubineau et al., 1994; Shapiro and Vigalok, 2008; Chandra and Fokin, 2009). These terms are often used interchangeably, although they refer to reactions that may occur under quite different conditions. The nomenclature that is used most often is as follows:The “in-water” reactions describe the cases in which the reactants are water soluble, but also the cases in which the reaction occurs in micelles that are dispersed in water (see Section 3.3.3 for the award-winning micelle design by Lipshutz).The “on-water” reactions are those in which the insoluble reactants are stirred in aqueous emulsions or suspensions. Thus, they occur in heterogeneous systems (Klijn and Engberts, 2005; Narayan et al., 2005; Chandra and Fokin, 2009).“Water-promoted” organic reactions are those that show an outcome that is superior when the reactions are performed in water compared to traditional organic solvents.“In the presence of water” can be used broadly, but also more specifically, for the cases in which water is added to traditional organic solvents.
Effect of setting accelerator additive on short- and long-term properties of cold recycled mixture containing bitumen emulsion–cement composites
Published in Road Materials and Pavement Design, 2020
Seyed Yousof Abbasnejad, Amir Modarres
Figure 7 shows the SEM image of PC2S0 paste. In a conventional cement paste, three calcium aluminate (C3A) reacts right after contacting cement particles with water. This reaction results in the production of ettringite crystals (Janotka, 2001; Yuan, Yu, & Brouwers, 2017). The existence of C3A crystals in PC2S0 image indicates the retarding effect of bitumen emulsion on cement hydration and limited progression of C3A-water reaction in this paste. Figure 8(a) shows a sample micrograph of PC2S10 paste after partial curing at a magnification of 10,000x. In this figure, several ettringite crystals are found that are absent in PC2S0 micrograph as shown in Figure 7. With regard to Figure 8(b), the SEM image of PC2E0 paste showed highly similar morphological form and chemical structure to PC2S10. Apart from several elongated crystals in this micrograph, the dense and integrated structure indicates the formation of cementitious compositions after the partial curing period.
Ignition of combustible mixtures by hot particles at varying relative speeds
Published in Combustion Science and Technology, 2019
Thorsten Zirwes, Feichi Zhang, Thomas Häber, Henning Bockhorn
Figure 14 shows the reaction zone in terms of the water reaction rate (a), the temperature field (b) and velocity in the main flow direction (c) at the start of propagation away from the particle, which corresponds to a time shortly after Figure 12(c) and before Figure 12(d). The flame, that was previously stabilized in the recirculation zone, has moved further downstream. Because the particle is still heating up, the thermal boundary thickness increases which allows the flame to stabilize further downstream. When the surface temperature reaches K as shown in Figure 14, the point of stabilization has moved just beyond the region of flow reversal. From this time on, the flame propagates through the rest of the computational domain.
Colloidal cesium lead bromide-based anisotropic nanorods for improving outcoupling in perovskite light-emitting diodes
Published in Journal of Information Display, 2023
Muhammad Imran Saleem, Jeong-Hwan Lee
The anisotropic CsPbBr3 nanorods are synthesized by the hot-injection method with the assistance of surface ligand modification of non-luminescent Cs4PbBr6 NPDs at the oil–water interface [36]. The stoichiometric amount of Cs-oleate was injected into a 100 mL three-neck flask containing 0.2 mmol PbBr2, 10 mL ODE, 1 mL OA, and 1 mL OLM at 140°C. The reaction is terminated with ice water after 10 s. The mixture was centrifuged at 8000 rpm for 5 min to separate the NPDs Cs4PbBr6 NCs, and the precipitate was redispersed in 10 mL cyclohexane for an oil–water reaction.