Magnetic Anisotropy Switch: Easy Axis to Easy Plane Conversion and Vice Versa

The rational design of the magnetic anisotropy of molecular materials constitutes a goal of primary importance in molecular magnetism. Indeed, the applications of molecular nanomagnets, such as single‐molecule magnets and molecular magnetic refrigerants, depend on the full control over this property. Axially anisotropic magnetic systems are frequently classified as easy axis or easy plane, depending on whether the lowest energy is obtained by application of a magnetic field parallelly or perpendicularly to the unique axis. Here, the magnetic anisotropy of three lanthanide complexes is studied as a function of magnetic field and temperature. It is found that for two of these the type of magnetic anisotropy switches as a function of these parameters. Thus, this paper experimentally demonstrates that the magnetic anisotropy is not uniquely defined by the intrinsic electronic structure of the systems in question but can also be reversibly switched using external stimuli: temperature and magnetic field.     

Databases for computational thermodynamics and diffusion modeling

Databases for computational thermodynamics and diffusion modeling can be applied to the prediction of phase diagrams and microstructural evolution. These predictions can be used for alloy and process design, as well as to improve modeling capabilities that would decrease the time for new alloy and process development. Databases that are currently available to scientists, engineers, and students need to be expanded and improved. Accordingly, a workshop was held March 21–22, 2002, to identify the database and information delivery tool needs of industry and education. As a result of the workshop a roadmap was developed to show how these needs can be met during the next decade in a cost-effective way through expanded collaborative efforts in education, basic research, and database development. The workshop consisted of a series of invited talks given to the group as a whole followed by general discussions of needs and benefits, and the construction of a roadmap of future activities. A brief report of a follow-up meeting held on May 27, 2003, is given in the Appendix.     

The challenge of networked enterprises for cloud computing interoperability

Manufacturing enterprises have to organize themselves into effective system architectures forming different types of Networked Enterprises (NE) to match fast changing market demands. Cloud Computing (CC) is an important up to date computing concept for NE, as it offers significant financial and technical advantages beside high-level collaboration possibilities. As cloud computing is a new concept the solutions for handling interoperability, portability, security, privacy and standardization challenges have not been solved fully yet. The paper introduces the main characteristics of future Internet-based enterprises and the different CC models. An overview is given on interoperability and actual standardization issues in CC environments. A taxonomy on possible connecting forms of networked enterprises and cloud-based IT systems with reference on interoperability is introduced, parallel presenting four use cases as well. Finally, an example of connecting cloud and NE is presented as an effective application of cloud computing in manufacturing industry.     

Mass transfer in tube banks with two-phase flow

The fluid dynamic behaviour and the liquid-solid mass transfer to horizontal cylinders, under bubble induced convection, was investigated. The gas void fraction was measured and overall mass transfer coefficients were determined for single cylinders as well as for banks of tubes with various characteristics.     

Life reflection: A social–cognitive analysis of life review.

Life review and reminiscence are 2 concepts used to describe the phenomenon of people reflecting on their lives. Rather than used synonymously, these 2 concepts need to be distinguished on the basis of a social–cognitive process analysis. For that purpose, life reflection is introduced as a new term. Evidence shows that life reflection is a social–cognitive process that begins in adolescence and continues across the life span. It serves different functions across the life span, but at all ages it contributes to self-insight and a self-critical perspective. Striving for new insights about oneself and about life in general is challenging and taxing. Reflecting together with a trusted person, thus, may facilitate the process. A study testing and supporting some of these propositions is reported. Results are discussed in the context of lifespan theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Emotional versus neutral expressions and perceptions of social dominance and submissiveness.

Emotional expressions influence social judgments of personality traits. The goal of the present research was to show that it is of interest to assess the impact of neutral expressions in this context. In 2 studies using different methodologies, the authors found that participants perceived men who expressed neutral and angry emotions as higher in dominance when compared with men expressing sadness or shame. Study 1 showed that this is also true for men expressing happiness. In contrast, women expressing either anger or happiness were perceived as higher in dominance than were women showing a neutral expression who were rated as less dominant. However, sadness expressions by both men and women clearly decreased the extent to which they were perceived as dominant, and a trend in this direction emerged for shame expressions by men in Study 2. Thus, neutral expressions seem to be perceived as a sign of dominance in men but not in women. The present findings extend our understanding of the way different emotional expressions affect perceived dominance and the signal function of neutral expressions—which in the past have often been ignored. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of Brønsted acidity in the SCR of NO over Fe-MFI catalysts

The selective catalytic reduction (SCR) of NO with isobutane and with NH₃ was studied over Fe-MFI catalysts which differ strongly in Brønsted acidity but are similar in Fe content and structure of Fe sites, having shown similar activity in N₂O decomposition in related work. The catalysts were prepared by exchange of Na-ZSM-5 (Si/Al ca. 14) with Fe²⁺ ions formed in situ by acidic dissolution of Fe powder and by steam extraction of framework iron from Fe-silicalite or from H-[Fe]-ZSM-5 (Si/Al ca. 30). The characterization of acidic properties by ammonia TPD and by IR of adsorbed pyridine at different temperatures revealed marked differences in acidity between exchanged and steam-activated samples, the latter being (almost) void of strong Brønsted sites. The structural similarity of the iron sites was confirmed by UV–Vis and EPR spectroscopic results. The weakly acidic samples were inferior both in isobutane-SCR and in ammonia-SCR. With isobutane, dramatic differences over the whole range of parameters studied imply a vital role of Brønsted acidity in the reaction mechanism (e.g. in isobutane activation). In NH₃-SCR, large reaction rates were achieved with non-acidic catalysts as well, but a promoting effect of acidity was noted for catalysts that contain the iron in the most favorable site structure (oligomeric Fe oxo clusters). This suggests that an acid-catalyzed step (e.g. the decomposition of NH₄NO₂) may be rate-limiting at low temperatures.     

The intensity of facial expression is determined by underlying affective state and social situation.

The present study concerned the influence of the presence of others on facial expressions of emotion. The proposition that facial expressive displays are better predicted by the social context than by emotional state (A. J. Fridlund, 1991) was tested in an experiment varying both the sociality of the context and the intensity of the emotion elicitor as well as the relationship between expressor and audience. The results indicate that the intensity of expressive displays cannot be satisfactorily predicted by either of these factors alone but is influenced by a complex interplay of all 3 factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Transfer studies of polystyrene nanoparticles in the ex vivo human placenta perfusion model: key sources of artifacts

Nanotechnology is a rapidly expanding and highly promising new technology with many different fields of application. Consequently, the investigation of engineered nanoparticles in biological systems is steadily increasing. Questions about the safety of such engineered nanoparticles are very important and the most critical subject with regard to the penetration of biological barriers allowing particle distribution throughout the human body. Such translocation studies are technically challenging and many issues have to be considered to obtain meaningful and comparable results. Here we report on the transfer of polystyrene nanoparticles across the human placenta using an ex vivo human placenta perfusion model. We provide an overview of several challenges that can potentially occur in any translocation study in relation to particle size distribution, functionalization and stability of labels. In conclusion, a careful assessment of nanoparticle properties in a physiologically relevant milieu is as challenging and important as the actual study of nanoparticle–cell interactions itself.