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To collect and dispose growing amounts of municipal solid waste (MSW) changed to be a hot topic along with the rapid urbanization in past decades. Cities are more and more dependent on the incineration instead of landfilling due to the cost-efficiency and environmental concerns. Considering the limited number of incineration plants and complicated situation of transportation in both spatial and temporal dimensions in different cities, the optimal routing for waste collection turns to be meaningful research topic. In this research, the ant colony optimization (ACO)-based multi-objective routing model coupled with min-max model and Dijkstra’s algorithm is proposed to address the question of which route to take from these waste-generating points to the target incineration plant(s) considering travel time, accident probability (black spots), and population exposure, so as to support the routing decision-making. The model is successfully implemented in Singapore and the effectiveness of the model has also been justified. Besides, few limitations of this research have also been discussed, some of which would also be the future directions of our research, especially the design and integration of a web-based routing decision-making support system. [ABSTRACT FROM PUBLISHER]

A new class of bisthiourea-functionalized molecular clips were designed and synthesized for anion recognition. Clip 1 showed excellent affinity to the biologically relevant fluoride ion in a 1:1 ratio as shown by UV-vis, �H and �9F NMR studies. Moreover, the binding was accompanied with visually noticeable color changes, enabling the compound to act as a colorimetric fluoride sensor. [ABSTRACT FROM AUTHOR]

Abstract: A novel ratiometric fluorescent sensor bearing two benzimidazole groups has been synthesized. The sensor showed a ratiometric fluorescence response with an enhancement of the ratios of emission intensities at 443 and 378 nm from 0.17 to 3.21 for Cr3+. The ratios of emission intensities at 443 and 380 nm were enhanced from 0.40 to 2.09 for Fe3+. Fe3+ revealed significant adsorption in the UV–vis region, which can be used to discriminate Cr3+ and Fe3+. Detection limits of the method for Cr3+ and Fe3+ were 25 μM and 2 μM, respectively. In addition, the sensor showed good selectivity to Cr3+ and Fe3+ over other metal ions. [Copyright &y& Elsevier]

We designed and synthesized a "hybrid" molecular container 1, which is structurally related to both cucurbit[n]uril (CB[n]) and pillar[n]arene type receptors. Receptor 1 was fully characterized by 1 H NMR, 13 C NMR, IR, MS and X-ray single crystal diffraction. The self-association behavior, host-guest recognition properties of 1, and the [salt] dependence of K a were investigated in detail by 1 H NMR and isothermal titration calorimetry (ITC). Optical transmittance and TEM measurements provide strong evidence that receptor 1 undergoes co-assemble with amphiphilic guest C10 in water to form supramolecular bilayer vesicles (diameter 25.6±2.7 nm, wall thickness ≈3.5 nm) that can encapsulate the hydrophilic anticancer drug doxorubicin (DOX) and the hydrophobic dye Nile red (NR). The release of encapsulated DOX or NR from the vesicles can be triggered by hexamethonium (8 c) or spermine (10) which leads to the disruption of the supramolecular vesicles., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)