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The Book-Makers: A History of the Book in 18 Remarkable Lives by Adam Smyth The Bodley Head, [pounds sterling]25, pp. 380 For some readers this book will have the charm [...]

I found Fr. David Neuhaus' views on the situation in Israel and Palestine disturbing and one-sided. I agree wholeheartedly with him that Netanyahus government will always be an obstacle to [...]

Disassembly is an inevitable step in the recovery of valuable materials from end-of-life (EoL) mobile phones. Although a Hybrid Graph is one of the prevalent method for disassembly modeling, it cannot accurately describe the subassembly disassembling process. In this paper, an improved disassembly hybrid graph model (IDHGM) for selective disassembly sequence planning is proposed for the limitations of the subassembly disassembling process of EoL mobile phones. The containment, exclusion, and subassembly are considered in view of the close connection of mobile phone parts and the occurrence of interlocking between parts. Based on the different disassembly sequences of the same part, a time cell array is used to calculate the disassembly time. The disassembly sequence is optimized by the ant colony algorithm and disassembly time is set as the optimization objective. “Honor 6” mobile phone was selected as a case study to demonstrate the feasibility of the proposed model. The results show that the disassembly sequence generated by IDHGM takes less disassembly time and can accurately describe the subassembly disassembling process.

A plausible route for the spontaneous synthesis of an activated ribonucleotide that is poised for polymerization has been put forth (Powner et al.(2009) Nature, 459, 239–242). A key step in this route necessitates the regioselective phosphorylation of the secondary alcohol on C3′of an anhydroarabinonucleoside in the presence of the primary alcohol on C5′. Here, we propose that this regioselectivity relies on electron delocalization between a lone pair (n) of O5′and an antibonding orbital (π*) of C2N3. This n→π* interaction modulates reactivity without the use of a protecting group. Thus, a stereoelectronic effect could have opened a gateway to the “RNA world”, the chemical milieu from which the first forms of life are thought to have emerged on Earth some 4 billion years ago.

Neodymium-iron-boron (NdFeB) magnets offer the strongest magnetic field per unit volume, and thus, are widely used in clean energy applications such as electric vehicle motors. However, rare earth elements (REEs), which are the key materials for creating NdFeB magnets, have been subject to significant supply uncertainty in the past decade. NdFeB magnet-to-magnet recycling has recently emerged as a promising strategy to mitigate this supply risk. This paper assesses the environmental footprint of NdFeB magnet-to-magnet recycling by directly measuring the environmental inputs and outputs from relevant industries and compares the results with production from “virgin” materials, using life cycle assessments. It was found that magnet-to-magnet recycling lowers environmental impacts by 64–96%, depending on the specific impact categories under investigation. With magnet-to-magnet recycling, key processes that contribute 77–95% of the total impacts were identified to be (1) hydrogen mixing and milling (13–52%), (2) sintering and annealing (6–24%), and (3) electroplating (6–75%). The inputs from industrial sphere that play key roles in creating these impacts were electricity (24–93% of the total impact) and nickel (5–75%) for coating. Therefore, alternative energy sources such as wind and hydroelectric power are suggested to further reduce the overall environmental footprint of NdFeB magnet-to-magnet recycling.