Enhanced photochemical hydrogen production by a molecular diiron catalyst incorporated into a metal-organic framework.

A molecular proton reduction catalyst [FeFe](dcbdt)(CO)6 (1, dcbdt = 1,4-dicarboxylbenzene-2,3-dithiolate) with structural similarities to [FeFe]-hydrogenase active sites has been incorporated into a highly robust Zr(IV)-based metal-organic framework (MOF) by postsynthetic exchange (PSE). The PSE protocol is crucial as direct solvothermal synthesis fails to produce the functionalized MOF. The molecular integrity of the organometallic site within the MOF is demonstrated by a variety of techniques, including X-ray absorption spectroscopy. In conjunction with [Ru(bpy)3](2+) as a photosensitizer and ascorbate as an electron donor, MOF-[FeFe](dcbdt)(CO)6 catalyzes photochemical hydrogen evolution in water at pH 5. The immobilized catalyst shows substantially improved initial rates and overall hydrogen production when compared to a reference system of complex 1 in solution. Improved catalytic performance is ascribed to structural stabilization of the complex when incorporated in the MOF as well as the protection of reduced catalysts 1(-) and 1(2-) from undesirable charge recombination with oxidized ascorbate

When routine calls for information become interpersonally sensitive

This paper examines interpersonally sensitive exchanges in two calls for information to the call centre of a public transport company. In order to provide relevant information and facilitate sequence progressivity, the agents need to go through specific steps. Although this is typical of institutional settings, customers may not necessarily be aware of them. The excerpts examined in this paper show how the customers’ lack of knowledge of the institutional steps the agents have to go through to attend to their requests and customers’ claims to product knowledge, coupled with the agents’ labour intensive work at the call centre, provide fertile ground for the agents’ verbal outbursts which are oriented to as interpersonally sensitive by the customers in so far as they are interpreted as inappropriate and potentially impolite. The analysis draws on the notion of face and incorporates a variety of concepts from pragmatics and Conversation Analysis

Exploring the moral compass: denunciations in a Facebook carpool group

With the advent of the internet and social media, car and vanpooling have become easily available alternatives to public transport in many parts of the world. This paper draws on publicly available data from a Facebook car and vanpooling group used by Slovenian cross-border commuters to make their journeys to and from Austria more economically sustainable. It examines public displays of moral indignation following allegations of malpractice by relatively new members whose whole purpose in joining the group was to earn a living from driving vans across borders. Vanpool users collaboratively denounce van service providers for transgressing some of the social responsibilities that ought to bind members of the group together and for their lack of accountability. The accusations which entail exaggerations, complaints, insults and threats, among other hostile verbal attacks, convey moral indignation and are similarly resisted and challenged by the drivers. They offer a window into conflicting behavioural expectations at a time of socioeconomic change and transition. The alleged lack of service van providers’ accountability which, in turn, informs the van users’ displays of moral indignation is indicative of the moral relativism that emerges as a result of the relocalisation and transforming nature of a contemporary global practice at a time when changes in social life are underway. The primacy of the economic return that vanpooling provides van service providers and cross-commuters with is oriented to by the former as outstripping typical social responsibilities related to the provision of the regulated services, and by the latter, as morally unjustifiable despite acknowledging its economic value

Momentum Spectra for Dynamically Assisted Schwinger Pair Production

Recently the dynamically assisted Schwinger mechanism, i.e., electron-positron pair production from vacuum by a combination of laser pulses with different time scales has been proposed. The corresponding results, which suggest that the rate of produced pairs is significantly enhanced by dynamical effects, are verified. Employing the framework of quantum kinetic theory intrinsically enables us to additionally provide momentum space information on the generated positron spectrum.Comment: 6 pages, 7 figure

Optimized Synthesis of Tetrafluoroterephthalic Acid: A Versatile Linking Ligand for the Construction of New Coordination Polymers and Metal-Organic Frameworks

Pure 2,3,5,6-tetrafluoroterephthalic acid (H(2)tfBDC) is obtained in high yields (95%) by reacting 1,2,4,5-tetrafluorobenzene with a surplus (>2 equiv) of n-butyllithium in tetrahydrofuran (THF) and subsequent carbonation with CO2 without any extensive purification procedure. A single crystal X-ray structure analysis of H2tfBDC (1) confirms former data obtained for a deuterated sample (P (1) over bar, Z = 1). Recrystallization from water/acetone leads to single crystals of H(2)tfBDC center dot 2H(2)O (2, P2(1)/c, Z. 2), where an extensive hydrogen bonding network is found. By reacting H2tfBDC with an aqueous ammonia solution, single crystals of (NH4)(2)tfBDC (3, C2/m, Z. 2) are obtained. 3 is thermally stable up to 250 degrees C and shows an enhanced solubility in water compared to H(2)tfBDC. Monosubstituted 2,3,5,6-tetrafluorobenzoic acid (H(2)tfBC, 4) is obtained by reacting 1,2,4,5-tetrafluorobenzene with stoichiometric amounts (1 equiv) of n-butyllithium in THF. Its crystal structure (Fdd2, Z = 16) shows dimeric units as characteristic structural feature

Machine Translated Atwood: Utopia or Dystopia?

Margaret Atwood’s masterful linguistic creativity exceeds the limits of ordinary discourse. Her elliptical language contributes to interpretative gaps, while the ambiguity and openness of her texts intentionally deceive the reader. The translator of Atwood’s texts therefore faces the challenge of identifying the rich interpretative potential of the original, as well as of preserving it in the target language. Witnessing the rise of artificial intelligence, a natural question arises whether a human translator could ever be replaced by a machine in translating such challenging texts. This article aims to contribute to the ongoing debate on literary machine translation by examining the translations of Atwood’s “Life Stories” generated by two neural machine translation (NMT) systems and comparing them to those produced by translation students. We deliberately chose a literary text where the aesthetic value depends mostly on the author’s personal style, and which we had presumed would be problematic to translate

THE ROLE OF TRUST IN THE FOOD SUPPLY CHAIN

Abstract Dimensions of supply chain relationships such as trust, commit ment, co -operation, communicat ion and adaptation play a vital role for a successful and efficient flow of products and/or services. As recent scandals in the field o f food industry have shown, t his phenomenon has not received enough attention. Namely, studies of supply chain relationships have primarily focused on relationship processes as such, but have failed to acknowledge their impact on all relevant parties or the overall reputation. Hence, in light of relevant studies the present paper aims to identify and discuss problems in relationships between different parties in food supply chain in Slovenia, fro m the consumers' viewpoint. More specifically, the object ive is to examine the role of trus t as seen in Slovene consumers' react ions to food scandals in Slovenia (and Europe) covered by different media. The findings indicate that consumers not only mistrust the institutions responsible for food safety and quality assurance, but also the claims on products

Asymmetric Synthesis of b-Substituted a-Methylenebutyro- lactones via TRIP-Catalyzed Allylation: Mechanistic Studies and Application to the Synthesis of (S)-(À)-Hydroxymatairesinol

Abstract: Asymmetric allylation of (hetero)aromatic aldehydes by a zinc(II)-allylbutyrolactone species catalyzed by a chiral BINOL-type phosphoric acid gave b-substituted a-methylenebutyrolactones in 68 to > 99% ee and 52-91% isolated yield. DFT studies on the intermediate Zn 2+ -complex -crucial for chiral induction -suggest a six-membered ring intermediate, which allows the phosphoric acid moiety to activate the aldehyde. The methodology was applied to the synthesis of the antitumour natural product (S)-(À)-hydroxymatairesinol