Reactivity of a trimethylstannyl molybdenum complex in mesoporous MCM-41

A highly thermostable tin–molybdenum complex is encapsulated into the hexagonal mesoporous channel host MCM-41 and thermally transformed into supported metal clusters

Sensitivity to lunar cycles prior to the 2007 eruption of Ruapehu volcano

A long-standing question in Earth Science is the extent to which seismic and volcanic activity can be regulated by tidal stresses, a repeatable and predictable external excitation induced by the Moon-Sun gravitational force. Fortnightly tides, a similar to 14-day amplitude modulation of the daily tidal stresses that is associated to lunar cycles, have been suggested to affect volcano dynamics. However, previous studies found contradictory results and remain mostly inconclusive. Here we study how fortnightly tides have affected Ruapehu volcano (New Zealand) from 2004 to 2016 by analysing the rolling correlation between lunar cycles and seismic amplitude recorded close to the crater. The long-term (similar to 1-year) correlation is found to increase significantly (up to confidence level of 5-sigma) during the similar to 3 months preceding the 2007 phreatic eruption of Ruapehu, thus revealing that the volcano is sensitive to fortnightly tides when it is prone to explode. We show through a mechanistic model that the real-time monitoring of seismic sensitivity to lunar cycles may help to detect the clogging of active volcanic vents, and thus to better forecast phreatic volcanic eruptions

A Tax on Tax Revenue. The Incentive Effects of Equalizing Transfers: Evidence from Germany

Several recent studies suggest that equalizing transfers in a federal system may distort the tax policy decisions of states. We study this issue for the German federal fiscal system. In a simple theoretical model, we first identify a substitution and an income effect of equalizing transfers. Our main hypothesis is that both effects should tend to reduce tax revenue of German states. We perform various empirical tests which confirm this hypothesis.

A new lattice Boltzmann model for interface reactions between immiscible fluids

In this paper, we describe a lattice Boltzmann model to simulate chemical reactions taking place at the interface between two immiscible fluids. The phase-field approach is used to identify the interface and its orientation, the concentration of reactant at the interface is then calculated iteratively to impose the correct reactive flux condition. The main advantages of the model is that interfaces are considered part of the bulk dynamics with the corrective reactive flux introduced as a source/sink term in the collision step, and, as a consequence, the model’s implementation and performance is independent of the interface geometry and orientation. Results obtained with the proposed model are compared to analytical solution for three different benchmark tests (stationary flat boundary, moving flat boundary and dissolving droplet). We find an excellent agreement between analytical and numerical solutions in all cases. Finally, we present a simulation coupling the Shan Chen multiphase model and the interface reactive model to simulate the dissolution of a collection of immiscible droplets with different sizes rising by buoyancy in a stagnant fluid

High-intracavity-power thin-disk laser for the alignment of molecules

We propose a novel approach for strong alignment of gas-phase molecules for experiments at arbitrary repetition rates. A high-intracavity-power continuous-wave laser will provide the necessary ac electric field of $\!10^{10}$- $10^{11}~\text{W}/\text{cm}^2$. We demonstrate thin-disk lasers based on Yb:YAG and Yb:Lu$_2$O$_3$ in a linear high-finesse resonator providing intracavity power levels in excess of 100~kW at pump power levels on the order of 50~W. The multi-longitudinal-mode operation of this laser avoids spatial-hole burning even in a linear standing-wave resonator. The system will be scaled up as in-vacuum system to allow for the generation of fields of $10^{11}~\text{W}/\text{cm}^2$. This system will be directly applicable for experiments at modern X-ray light sources, such as synchrotrons or free-electron lasers, which operate at various very high repetition rates. This would allow to record molecular movies through temporally resolved diffractive imaging of fixed-in-space molecules, as well as the spectroscopic investigation of combined X-ray-NIR strong-field effects of atomic and molecular systems

Teacher´s feedback and social integration: is there a link between social referencing theory and social integration in school

Schüler mit sonderpädagogischem Förderbedarf werden im Zuge der Umsetzung der UN-Behindertenrechtskonvention perspektivisch eher an allgemeinbildenden Schulen unterrichtet. Im folgenden Beitrag wird aus dem sozialpsychologischen Ansatz des „social referencings“ ein Modell zur Entstehung sozialer Integrationsprozesse in der Schule abgeleitet. Das Modell liefert Ansatzpunkte, wie Lehrer die soziale Integration ihrer Schüler günstig beeinflussen könnten. In einer Querschnittstudie mit 296 Schülerinnen und Schülern wurde überprüft, ob Lehrersympathie, Schulleistung oder die von den Klassenkameraden vermutete Lehrersympathie einen Einfluss auf die soziale Integration eines Schülers haben. Signifikante Effekte wurden insbesondere für die Lehrersympathie festgestellt. (DIPF/Orig.)Due to the incipient development towards inclusive education, the German school system is facing severe changes. One of the core issues therein is the social integration of children with special educational needs. Several national and international studies suggest that the social integration of these children seems to be less satisfactory put into practice than initially intended. Based on social referencing theory the present paper develops an alternative model of social integration in school that emphasizes teachers’ relevance for integration process. A cross-section study with 296 pupils suggests that teachers valuation and teachers valuation as perceived by classmates could in fact influence social integration of a single student in everyday school life. (DIPF/Orig.