Defluorosilylation of Industrially Relevant Fluoroolefins Using Nucleophilic Silicon Reagents

A number of new magnesium and lithium silyl reagents were prepared and shown to be outstanding nucleophiles in reactions with industrially relevant fluoroolefins. These reactions result in a net transformation of either sp² or sp³ C?F bonds into C?Si bonds by two modes of nucleophilic attack (S_NV or S_N2′). The methods are mild, proceeding with high chemo‐ and regioselectivity. Mechanistic pathways are described that lead to new substitution patterns from HFO‐1234yf, HFO‐1234ze, and HFO‐1336mzz, previously inaccessible by transition metal catalyzed difluorosilylation routes.     

Optimization of spin-triplet supercurrent in ferromagnetic Josephson junctions

We have observed long-range spin-triplet supercurrents in Josephson junctions containing ferromagnetic (F) materials, which are generated by noncollinear magnetizations between a central Co/Ru/Co synthetic antiferromagnet and two outer thin F layers. Here we show that the spin-triplet supercurrent is enhanced up to 20 times after our samples are subject to a large in-plane field. This occurs because the synthetic antiferromagnet undergoes a "spin-flop" transition, whereby the two Co layer magnetizations end up nearly perpendicular to the magnetizations of the two thin F layers. We report direct experimental evidence for the spin-flop transition from scanning electron microscopy with polarization analysis and from spin-polarized neutron reflectometry. These results represent a first step toward experimental control of spin-triplet supercurrents.     

Challenges and applications of isotachophoresis coupled to mass spectrometry: A review

Electrophoretic separations are of growing interest to tackle complex analytical challenges. Nevertheless, capillary electrophoresis, as the most common mode, still suffers from insufficient detection limits due to low capillary loadability. ITP is of growing interest as preconcentration method for capillary electrophoresis and is also interesting to be applied as an independent analytical method. While mass spectrometric detection is common for capillary electrophoresis, the combination of ITP with MS is still a niche technique. In this work, we want to give an overview on isotachophoretic effects in CE-MS and ITP-MS methods, as well as coupling techniques of ITP with CE-MS. The challenges and possibilities associated with mass spectrometric detection in ITP and its coupling to capillary electrophoresis are critically discussed.     

Emotional voices in context: a neurobiological model of multimodal affective information processing

Just as eyes are often considered a gateway to the soul, the human voice offers a window through which we gain access to our fellow human beings? minds – their attitudes, intentions and feelings. Whether in talking or singing, crying or laughing, sighing or screaming, the sheer sound of a voice communicates a wealth of information that, in turn, may serve the observant listener as valuable guidepost in social interaction. But how do human beings extract information from the tone of a voice? In an attempt to answer this question, the present article reviews empirical evidence detailing the cerebral processes that underlie our ability to decode emotional information from vocal signals. The review will focus primarily on two prominent classes of vocal emotion cues: laughter and speech prosody (i.e. the tone of voice while speaking). Following a brief introduction, behavioral as well as neuroimaging data will be summarized that allows to outline cerebral mechanisms associated with the decoding of emotional voice cues, as well as the influence of various context variables (e.g. co-occurring facial and verbal emotional signals, attention focus, person-specific parameters such as gender and personality) on the respective processes. Building on the presented evidence, a cerebral network model will be introduced that proposes a differential contribution of various cortical and subcortical brain structures to the processing of emotional voice signals both in isolation and in context of accompanying (facial and verbal) emotional cues.     

Homogenization of layered materials with rigid components in single-slip finite crystal plasticity

We determine the effective behavior of a class of composites in finite-strain crystal plasticity, based on a variational model for materials made of fine parallel layers of two types. While one component is completely rigid in the sense that it admits only local rotations, the other one is softer featuring a single active slip system with linear self-hardening. As a main result, we obtain explicit homogenization formulas by means of \(\Gamma \)-convergence. Due to the anisotropic nature of the problem, the findings depend critically on the orientation of the slip direction relative to the layers, leading to three qualitatively different regimes that involve macroscopic shearing and blocking effects. The technical difficulties in the proofs are rooted in the intrinsic rigidity of the model, which translates into a non-standard variational problem constraint by non-convex partial differential inclusions. The proof of the lower bound requires a careful analysis of the admissible microstructures and a new asymptotic rigidity result, whereas the construction of recovery sequences relies on nested laminates.     

A molecular Mo4Bi4 framework composed exclusively of unsupported metal-metal bonds

Reaction of [Cp(2)MoH(2)] with bismuth allyloxide, [Bi{OCH(CH(3))CH==CH(2)}(3)], gave rise to an extended octanuclear complex wherein two cyclic Mo(2)Bi(2) units composed of four Mo-Bi bonds are linked by a Bi-Bi bond. The fact that the construction of such an assembly could be accomplished only in the case of a monomethylation of the parent allyl residue demonstrates a subtle substituent effect.