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The reactions under which interstitial structures of Pd form are profoundly important and prevalent in catalysis; the formation and stability of Pd hydride structures are well understood, however, interstitial structures of the carbide and nitride are relatively under explored. This work reports a systematic study of the formation and stability of PdCx and PdNx at elevated temperatures and different atmospheres using in situ Pd L3 edge XANES spectroscopy. These studies were further complemented by the application of 14N MAS‐NMR experiments and computational DFT investigations. The experiments confirmed that PdCx was significantly more stable than PdNx; 14N MAS‐NMR provided direct confirmation on the formation of the nitride, however, the XANES studies evidenced very limited stability under the conditions employed. Moreover, the results suggest that the formation of the nitride imparts some structural changes that are not entirely reversible under the conditions used in these experiments. This work provides important insights into the stability of interstitial structures of Pd and the conditions in which they could be employed for directed catalytic processes. [ABSTRACT FROM AUTHOR]

Previous work by Pettit et al (2017) drew on Socio-technical Transitions Theory (STT) to contextualise recent developments in the technological and operational eco-efficiency of ships which may ameliorate sustainability issues in shipping. Within STT the Multi-Level Perspective (MLP) is a framework used to explain the permeation of innovations into society (Geels, 2014). The framework has three levels: Landscape; Regime and Niche. In order to develop a better understanding of changes that may take place in the future, this paper uses the MLP to assess the broad range of challenges facing the shipping industry with respect to future CO2 emissions at each of the three levels. The framework is applied to four scenarios for global shipping in order to understand the potential range of outcomes for CO2 emissions. The four scenarios are: ‘Business as Usual’; ‘Managed Transition’; ‘Chaotic Transition’; and ‘Managed Degrowth’. It is contended that changes in the shipping industry alone are unlikely to lead to large-scale changes in its CO2 emissions. Under ‘Business as Usual’ conditions, CO2 emissions will continue to rise as the changes required at all three levels, but primarily at the regime level, will have limited impact. Under the other three scenarios, it is suggested that there is room for optimism that CO2 emissions will decline over time.

Sn-Beta has emerged as a state-of-the-art catalyst for a range of sustainable chemical transformations. Conventionally prepared by bottom-up hydrothermal synthesis methods, recent research has demonstrated the efficiency of several top-down methods of preparation. One attractive top-down approach is Solid-State Incorporation, where a dealuminated Beta zeolite is physically mixed with a solid Sn precursor, in particular Sn(II) acetate, prior to heat treatment at 550 °C. This procedure is fast and benign, and metal incorporation requires no solvents and hence produces no aqueous Sn-containing waste streams. Although the performances of these catalysts have been well explored in recent years, the mechanism of heteroatom incorporation remains unknown, and hence, opportunities to improve the synthetic procedure via a molecular approach remain. Herein, we use a range of in situ spectroscopic techniques, alongside kinetic and computational methods, to elucidate the mechanisms that occur during preparation of the catalyst, and then improve the efficacy of the synthetic protocol. Specifically, we find that successful incorporation of Sn into the lattice occurs in several distinct steps, including (i) preliminary coordination of the metal ion to the vacant lattice sites of the zeolite during physical grinding; (ii) partial incorporation of the metal ion into the zeolite framework upon selective decomposition of the acetate ligands, which occurs upon heating the physical mixture in an inert gas flow from room temperature to 550 °C; and (iii) full isomorphous substitution of Sn into the lattice alongside its simultaneous oxidation to Lewis acidic Sn(IV), when the physically mixed material is exposed to air during a short (<1 h) isotherm period. Long isotherm steps are shown to be unnecessary, and fully oxidised Sn(IV) precursors are shown to be unsuitable for successful incorporation into the lattice. We also find that the formation of extra-framework Sn oxides is primarily dependent on the quantity of Sn present in the initial physical mixture. Based on these findings, we demonstrate a faster synthetic protocol for the preparation of Sn-Beta materials via Solid-State Incorporation, and benchmark their catalytic performance for the Meerwein-Ponndorf-Verley transfer hydrogenation reaction and the isomerisation of glucose to fructose. [ABSTRACT FROM AUTHOR]

We demonstrate a modified sol‐immobilization procedure using (MeOH)x/(H2O)1‐x solvent mixtures to prepare Pd/TiO2 catalysts that are able to reduce the formation of acid catalyzed products, e. g. ethers, for the hydrogenation of furfural. Transmission electron microscopy found a significant increase in polyvinyl alcohol (PVA) deposition at the metal‐support interface and temperature programmed reduction found a reduced uptake of hydrogen, compared to an established Pd/TiO2 preparation. We propose that the additional PVA hinders hydrogen spillover onto the TiO2 support and limits the formation of Brønsted acid sites, required to produce ethers. Elsewhere, the new preparation route was able to successfully anchor colloidal Pd to the TiO2 surface, without the need for acidification. This work demonstrates the potential for minimizing process steps as well as optimizing catalyst selectivity – both important objectives for sustainable chemistry. [ABSTRACT FROM AUTHOR]

When questioned about illegal, mood-altering substance use, 15,743 high school students surveyed in the last three years with the "Independent School Health Check" said alcohol is most commonly used. For the 30 days prior to filling out the survey, 33.9 percent of the students reported drinking, and 24.2 percent reported binge drinking (five or more drinks in a three-hour period). Although the majority who binged did so one to two times, 5.2 percent reported binging three or more times in the month. Being drunk comes with its own obvious health and safety risks, but binging and risk taking are often closely related: (1) 42 percent of bingers report cheating on tests and quizzes, 2.5 times greater than non-bingers; (2) 68 percent of bingers report oral-sex experience; (3) 53 percent report sexual intercourse; (4) 46.5 percent report marijuana use; (5) 20.1 percent report intercourse under influence; and (6) 17.0 percent report driving under the influence. Parties, particularly unchaperoned parties, represent the primary venue for binge drinking. When asked how often the student had attended parties in the month and how often the parties had been chaperoned by an adult, on average, binge drinkers reported attending unchaperoned parties 53.7 percent of the time, although the heaviest drinkers attended unchaperoned parties 63.5 percent of the time. Some drinking occurred after school--on average, 29.9 percent of the bingers drank with friends after school and 10.7 percent drank alone after school--although for the heaviest drinkers, the rate more than doubled. Adults have an important role to play in adolescent drinking and binging, particularly since adult permission is highly correlated to excess. For schools, these data suggest the benefits of adding the following aspects to school prevention programs: (1) Show students the data that demonstrates the association between binging and high-risk behaviors; (2) Encourage parents to be responsible chaperones at parties; (3) Alert parents to the illegality of and the dangers of allowing underage drinking; and (4) Help parents understand that they can make a difference in preventing the untold consequences of binge drinking for their children and their children's peers.