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Purpose: Occlusion plays a role in the execution of physical abilities in various. The aim of this study was to clarify the effect of clenching on the spinal alignment.

Beyond-lithium-ion batteries are promising candidates for high-energy-density, low-cost and large-scale energy storage applications. However, the main challenge lies in the development of suitable electrode materials. Here, we demonstrate a new type of zero-strain cathode for reversible intercalation of beyond-Li+ ions (Na+, K+, Zn2+, Al3+) through interface strain engineering of a 2D multilayered VOPO4-graphene heterostructure. In-situ characterization and theoretical calculations reveal a reversible intercalation mechanism of cations in the 2D multilayered heterostructure with a negligible volume change. When applied as cathodes in K+-ion batteries, we achieve a high specific capacity of 160 mA h g-1 and a large energy density of ~570 W h kg-1, presenting the best reported performance to date. Moreover, the as-prepared 2D multilayered heterostructure can also be extended as cathodes for high-performance Na+, Zn2+, and Al3+-ion batteries. This work heralds a promising strategy to utilize strain engineering of 2D materials for advanced energy storage applications.

© 2017 Two-dimensional (2D) materials have shown outstanding properties that make them the materials of choice for future semiconductor and flexible nanoelectronics. Hexagonal boron nitride nanosheet (BNNS) is one of the most studied 2D materials due to its extraordinary properties and potential applications. The synthesis of large, homogeneous, and few-layered BNNS, however, remains challenging. Among the various synthetic routes, chemical vapour deposition (CVD) is preferred on the grounds of its potential to yield large BNNS with controllable atomic layers and minimal contamination. We thus devote this review to the CVD growth of BNNS, and its characterization and applications. The recent progresses in the CVD growth of BNNS is firstly summarized from the aspects of precursors, substrates, growth mechanisms, and transfer techniques. This review then moves on to the characterization of few-atomic-layered h-BN sheets, covering a variety of microscopic and spectroscopic techniques that have proved useful for assessing the quality of BNNS. The applications of the BNNS are also summarized. This review is expected to instigate new methods and improvements in relation to the CVD growth of BNNS, which has enabled exceptional performance as a key component of nanoscale electronics.

Noncovalent functionalization of multi-walled boron nitride nanotubes (BNNTs) was achieved through water-soluble synthetic polymers wrapping. This led to the excellent disentanglement and dispersion of BNNTs in an aqueous phase. Various spectroscopic techniques revealed that π-π stacking interactions played the key role for the polymer-functionalization of BNNT. To show a prospective application of polymer-functionalized BNNTs in surface engineering fields, the disentangled BNNTs were used as the raw/starting materials for the creation of superhydrophobic surfaces.

An X-ray diffraction study has been carried out on boron nitride multi-walled nanotubes up to 19.1 GPa. The fit to the unit cell volumes yields a zero pressure bulk modulus K-0 = 34.9 +/- 1 GPa and its pressure derivative K-0' = 5.9 +/- 0.3. The compression is highly anisotropic, with the intertube-axis being close to 19 times more compressible than the a-axis. At the highest pressure the diffraction peaks were present even though they were weak and broad, which is in contrast to previous high-pressure Raman results.

Physical review / B 77, 235422 (2008). doi:10.1103/PhysRevB.77.235422, Published by APS, College Park, Md.

Die Bildung von Streptolysin-S durch den Streptococcus haemolyticus wird durch Zugabe von Nucleinsaure gesteigert. Die hemmende Wirkung von hamolysierenden Streptokokken auf Ehrlich-Ascitescarcinom und Yoshida-Ascitessarkom ist dadurch zu erklaren, das die Keime auf Kosten der in den Tumorzellen enthaltenen Ribonucleinsaure Streptolysin bilden. Anderen Keimen (s. Tabelle 2) fehlt diese Eigenschaft. Auf einschlagige alte Beobachtungen an Menschen wird hingewiesen. Da chemische Stoffe, welche die Hamolysin-S-Bildung durch Streptokokken vermindern oder gar aufheben, dies dadurch tun, das sie in den auch fur das Wachstum der Tumorzellen wichtigen Ribonucleinsaure-Stoffwechsel eingreifen, wurde unter derartigen Stoffen nach anticanceros wirkenden Mitteln gesucht und ein sehr wirksames (Azo 106) gefunden.

We first describe the synthesis of novel and highly porous boron nitride (BN) nanospheres (100-400 nm o.d.) that exhibit a rough surface consisting of open BN nanocones and corrugated BN ribbons-The material was produced by reacting B2O3 with nanoporous carbon spheres under nitrogen at ca. 1750 °C. The BN nanospheres were characterized using scanning electron microscopy, high-resolution electron microscopy, and electron energy loss spectroscopy. The porous BN spheres show relatively large surface areas of ca. 290 m2/g and exhibit surprisingly stable field emission properties at low turn-on voltages (e.g., 1-1.3 Vlμm). We attribute these outstanding electron emission properties to the presence of finite BN ribbons located at the surface of the nanospheres (exhibiting zigzag edges), which behave like metals as confirmed by first-principles calculations. In addition, our ab initio theoretical results indicate that the work function associated to these zigzag BN ribbons is 1.3 eV lower when compared with BN-bulk material. Refereed/Peer-reviewed