The second language acquisition (SLA) literature reports numerous studies of proficient second language (L2) speakers who diverge significantly from native speakers despite the evidence offered by the L2 input. Recent SLA theories have attempted to account for native speaker/non-native speaker (NS/NNS) divergence by arguing for the dissociation between syntactic knowledge and morpho(pho)nology. In particular, Lardiere (1998), Prévost and White (2000), and Goad and White (2004) claim that highly proficient learners have knowledge of the abstract syntactic properties of the language but occasionally fail to associate them with the correct morphological or phonological forms. On the other hand, theories that support partial availability of Universal Grammar (UG) (Tsimpli and Roussou 1991; Hawkins and Chan, 1997) argue for a problem in the syntax: while UG principles and operations are available in SLA, the formal features of the target language that are not instantiated in the L1 or have a different setting, cause learnability problems. This article discusses acquisitional data in the light of the Interpretability Hypothesis (Tsimpli and Mastropavlou, 2007), which is a reformulation of the SLA theory suggested by Tsimpli and Roussou (1991) in minimalist terms. It is argued that a minimalist approach to SLA can be implemented to specify the status of the features that are least accessible to re-setting in the SLA process, given (1) constraints on their learnability and (2), their setting in the L1 grammar. The phenomenon discussed concerns the use of the resumptive strategy in wh- subject and object extraction by intermediate and advanced Greek learners of English. It is proposed that the acceptability rate of pronouns in the extraction site is conditioned by the Logical Form (LF) interpretability of the features involved in the derivation. Hence, the interpretable features of animacy and discourse-linking are hypothesized to be involved in the analysis of English pronouns by Greek L2 learners, while the first language (L1) specification of resumptive pronouns as clusters of uninterpretable Case and Agreement features resists resetting.

A method for the synthesis of highly crystalline Rh₂P nanoparticles on SiO₂ support materials and their use as truly eterogeneous single-site catalysts for the hydroformylation of ethylene and propylene is presented. The supported Rh₂P nanoparticles were investigated by transmission electron microscopy and by infrared analysis of adsorbed CO. The influence of feed gas composition and reaction temperature on the activity and selectivity in the hydroformylation reaction was evaluated by using high throughput experimentation as an enabling element; core findings were that beneficial effects on the selectivity were observed at high CO partial pressures and after addition of water to the feed gas. The analytical and performance data of the materials gave evidence that high temperature reduction leading to highly crystalline Rh₂P nanoparticles is key to achieving active, selective, and longterm stable catalysts

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The mutual interaction between Rh nanoparticles and manganese/iron oxide promoters in silica-supported Rh catalysts for the hydrogenation of CO to higher alcohols was analyzed by applying a combination of integral techniques including temperature-programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS) and Fourier transform infrared (FTIR) spectroscopy with local analysis by using high angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) in combination with energy dispersive X-ray spectroscopy (EDX). The promoted catalysts show reduced CO adsorption capacity as evidenced through FTIR spectroscopy, which is attributed to a perforated core-shell structure of the Rh nano-particles in accordance with the microstructural analysis from electron microscopy. Iron and manganese occur in low formal oxidation states between 2+ and zero in the reduced catalysts as shown by using TPR and XAS. Infrared spectroscopy measured in diffuse reflectance at reaction temperature and pressure indicates that partial coverage of the Rh particles is maintained at reaction temperature under operation and that the remaining accessible metal adsorption sites might be catalytically less relevant because the hydrogenation of adsorbed carbonyl species at 523 K and 30 bar hydrogen essentially failed. It is concluded that Rh 0 is poisoned due to the adsorption of CO under the reaction conditions of CO hydrogenation. The active sites

The direct conversion of syngas to ethanol, typically using promoted Rh catalysts, is a cornerstone reaction in CO2 utilization and hydrogen storage technologies. A rational catalyst development requires a detailed structural understanding of the activated catalyst and the role of promoters in driving chemoselectivity. Herein, we report a comprehensive atomic‐scale study of metal–promoter interactions in silica‐supported Rh, Rh–Mn, and Rh–Mn–Fe catalysts by aberration‐corrected (AC) TEM. While the catalytic reaction leads to the formation of a Rh carbide phase in the Rh–Mn/SiO2 catalyst, the addition of Fe results in the formation of bimetallic Rh–Fe alloys, which further improves the selectivity and prevents the carbide formation. In all promoted catalysts, Mn is present as an oxide decorating the metal particles. Based on the atomic insight obtained, structural and electronic modifications induced by promoters are revealed and a basis for refined theoretical models is provided.

A facile synthesis approach for the synthesis of ternary intermetallic nanocrystals was demonstrated exemplarily with the Heusler compound Co2FeGa. The method, involving prefabricated multiwalled carbon nanotubes which act as a template and protective shell, results in the formation of mainly spherical, chemically stable, and crystalline nanoparticles with a well-defined diameter distribution. As an example, for novel functionalities arising from downscaling a bulk material, we observe an enhancement of the coercive field of the Co2FeGa nanocrystals by a factor of ≈30. Our work can facilitate the exploration and eventually the tuning of physical properties of ternary and other intermetallic compounds at the nanoscale.

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We present in situ experimental observations of fullerenes seamlessly fusing to single-walled carbon nanotubes. The morphing-entry of a fullerene to the interior of a nanotube is also captured. The confined (1D) motion of the newly-encapsulated fullerene within its host attests to the actual change from the exterior to interior.