Polymorphism of Ba2SiP4

The three‐dimensional SiP4 network in the known phosphidosilicate Ba2SiP4‐tI28 is analogous to β‐Cristobalite if oxygen is formally replaced by P–P dimers. Here we report a second polymorph Ba2SiP4‐oP56 [Pnma, a = 12.3710(4) Å, b = 14.6296(7) Å, c = 7.9783(3) Å; Z = 8] with chains of SiP4 tetrahedra connected by P–P bonds, reminiscent to the elusive fibrous SiO2. Ba2SiP4 is enantiotropic. The high temperature polymorph Ba2SiP4‐oP56 transforms to the low‐temperature phase Ba2SiP4‐tI28 at 650 °C and reconstructs to the high‐temperature modification at 1100 °C. DFT calculations predict an indirect optical bandgap of about 1.7 eV

Neue Kohlenstoffnanomaterialien aus massenselektierten molekularen Fragmenten

This work presents the results of various investigations regarding novel carbon nanomaterials. The general strategy to generate these materials was the use of the Low Energy Cluster Beam Deposition method which consists of the ionization and fragmentation of sublimable molecules in the gas phase followed by mass selection and soft-landing of the generated fragment ions on conducting or semiconducting surfaces. Also, the properties of already existing materials were modified by thermal treatment, doping with alkali metals and oxidation with atomic and molecular oxygen. This work contains studies concerning the following issues: - a series of measurements in which the binding energies between polyaromatic hydrocarbons (PAHs) and HOPG were measured by temperature programmed desorption in order to determine the graphite interlayer cohesion energy - the generation of PAH oligomers by deposition of dehydrogenated PAH fragments - a comparative study on the reactivity of various PAHs with atomic oxygen and also oxidized HOPG surfaces in order to explore the mediating role of these surfaces - an investigation of the efficiency and side reactions of the HF limination from fluorinated PAHs which are designed as precursors to generate curved nanostructures from planar molecules - attempts to purify single-walled carbon nanotubes by removing tensides or polymer coatings using thermal treatment and oxidation with atomic and molecular oxygen - the direct confirmation of covalent bonds between non-IPR fullerene cages by observing the sublimation of dimers - measurements on the properties of Cs doped non-IPR fullerene solids The properties of the generated materials were characterized using standard UHV methods of surface science: photoelectron spectroscopy, temperature programmed desorption, Raman spectroscopy as well as various microscopic methods

Zur Gliederung, Bildung und Altersstellung des Kalksteinschutts am Trauf der westlichen Schwäbischen Alb

Nach der Größe der Gesteinsstücke und dem Gehalt an Feinbestandteilen sind die Schuttmassen am Trauf der westlichen Alb drei verschiedenen Schuttarten zuzuordnen: dem „Schutt der Scherbenhalden", dem „grobstückigen Kalkschutt" und dem „feinsplitterigen Kalkschutt". Die beiden letzteren wurden während der Würmeiszeit gebildet und transportiert, während die Scherbenhalden hauptsächlich postglazial entstanden sind. Aus dem Profilaufbau, aus der Verbreitung und dem Tiefgang der vorhandenen Taschenböden ergibt sich, daß der „feinsplitterige Kalkschutt" nur während ausgesprochener Kaltzeiten (Hochglaziale) und stellenweise (besonders am Fuße des Albtraufs) in situ aus ursprünglich grobstückigem Kalkschutt gebildet wurde.researc

OS DESAFIOS DO ENSINO DA FILOSOFIA: EM BUSCA DE CRITÉRIOS DIDÁTICOS E METODOLÓGICOS

O presente artigo trata da necessidade de utilizardidáticas e metodologias no ensino médio adequadas àespecificidade da abordagem filosófica. A partir da análisedas relações entre a Educação e a Filosofia, procura-seidentificar os principais desafios que se relacionam à adoçãode uma práxis pedagógica capaz de superar a dicotomiaentre a teoria e a prática no processo de ensino-aprendizagemda disciplina

Sex-Specific Relationships Between Interoceptive Accuracy and Emotion Regulation

Over the last years, there has been a resurge in the interest to study the relationship between interoception and emotion. By now, it is well established that interoception contributes to the experience of emotions. However, it may also be possible that interoception contributes to the regulation of emotions. To test this possibility, we studied the relationship between interoception and emotion regulation in a sample of healthy individuals (n = 84). We used a similar heartbeat detection task and a similar self-report questionnaire for the assessment of interoceptive accuracy and emotion regulation as in previous studies. In contrast to previous studies, we differentiated between male and female individuals in our analyses and controlled our analyses for individual characteristics that may affect the relationship between interoceptive accuracy and emotion regulation. We found sex-differences in interoceptive accuracy and emotion regulation that amounted to a sex-specific relationship between interoceptive accuracy and emotion regulation: Whereas interoceptive accuracy was related to reappraisal but not to suppression in male individuals, interoceptive accuracy was unrelated to reappraisal and suppression in female individuals. These findings indicate that the relationship between interoception and emotion regulation is far more complex than has been suggested by previous findings. However, these findings nonetheless support the view that interoception is essential for both, the regulation and experience of emotions

Frequenzanalyse der Herzratenvariabilität in der Präventivmedizin

Aim was to test the ability of the parameter heart rate variability (HRV) to give insight into different stress-strain relations in the field of preventive medicine. Based on an overview of HRV`s physiology and potential, methodological aspects of HRV-analysis and HRV in the applied setting were explored. Results lead to the assumption that precise and valid measurements of inter-heartbeat-intervals are essential for HRV-analysis. Considering these criteria, HRV can complete the picture drawn by other physiological measures with respect to stress, strain and health risks of an individual

High‐Purity Er3_{3}N@C80_{80} Films: Morphology, Spectroscopic Characterization, and Thermal Stability

Films comprising the endohedral fullerene Er3N@C80 are deposited onto highly oriented pyrolytic graphite (HOPG) substrates in high purity enabled by performing mass-selected low-energy deposition from a cation beam. In the initial stage, the growth on HOPG is dominated by spontaneous nucleation of small 2D islands both on intact terraces as well as the step edges. The island growth exhibits strong differences from lms comprising other fullerenes grown by the same method. This behavior can be explained by the surface-diffusion-mediated nucleation model presented in previous work: Dominant components in the behavioural differences are a high intercage dispersion interaction and a lower kinetic energy of cages migrating on the surface in comparison with previously deposited materials. When annealed, the lms undergo several competing processes: A small fraction desorbs in the temperature range 700–800 K, another fraction forms covalent intercage bonds instead of the previous purely dispersive bonding mode, and a third fraction probably decomposes to small fragments

Reestruturação da agricultura familiar: o caso da feira de produtores de Erechim

This article is a descriptive case study about Agricultor Fair in Erechim-RS. This study has the purpose to feature the organizational way and how the agriculture products are exhibited. The familiar agriculture, with the increasing of the agroindustry has provided the development of several regions in Brazil, generating good jobs and profits. With the theoretical base and the case study of this fair, it was possible to identify the high level of satisfaction of the participants, as well as the good organizational structure of the place, either for of the municipal government or the exhibitors. The advantages of this activity are the services offered because they can provide practical situations for the costumers and also save time and space for the exhibitors because of the joint use of the place and sharing of tasks, as well as the increasing of the profits for the exhibitors.Este artigo é um estudo de caso, de caráter descritivo sobre a Feira de Produtores de Erechim-RS, tem por proposição caracterizar a forma organizacional da feira e comosão comercializados os produtos expostos. A agricultura familiar, com o advento da agroindústria tem propiciado o desenvolvimento de diversas regiões no Brasil, gerandoemprego e renda. Com a base teórica e o estudo de caso da feira foi possível identificar um alto nível de satisfação dos participantes, bem como, uma boa estrutura organizacional do local tanto em nível do poder público municipal, como também dos feirantes associados. As vantagens com esta atividade são que os serviços prestadosfornecem praticidade aos  consumidores, economia de tempo e de espaço aos feirantespelo uso conjunto do local e divisão de tarefas, como também aumento na receita dosfeirantes

Neuromuscular function and fatigue resistance of the plantar flexors following short-term cycling endurance training

Previously published studies on the effect of short-term endurance training on the neuromuscular function of the plantar flexors have shown that the H-reflex elicited at rest and during weak voluntary contractions was increased following the training regime. However, these studies did not test H-reflex modulation during isometric maximum voluntary contraction (iMVC) and did not incorporate a control group in their study design to compare the results of the endurance training group to individuals without the endurance training stimulus. Therefore, this randomized controlled study was directed to investigate the neuromuscular function of the plantar flexors at rest and during iMVC before and after eight weeks of cycling endurance training. Twenty-two young adults were randomly assigned to an intervention group and a control group. During neuromuscular testing, rate of torque development, isometric maximum voluntary torque and muscle activation were measured. Triceps surae muscle activation and tibialis anterior muscle co-activation were assessed by normalized root mean square of the EMG signal during the initial phase of contraction (0-100, 100-200 ms) and isometric maximum voluntary contraction of the plantar flexors. Furthermore, evoked spinal reflex responses of the soleus muscle (H-reflex evoked at rest and during iMVC, V-wave), peak twitch torques induced by electrical stimulation of the posterior tibial nerve at rest and fatigue resistance were evaluated. The results indicate that the endurance training did not lead to a significant change in any variable of interest. Data of the present study conflict with the outcome of previously published studies that have found an increase in H-reflex excitability after endurance training. However, these studies had not included a control group in their study design as was the case here. It is concluded that short-term cycling endurance training does not necessarily enhance H-reflex responses and fatigue resistance