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Purpose: To define the actions of boron on normal neurophysiology and glioblastoma growth. Materials and Methods: PubMed and other relevant databases were searched. Results: Discovery of novel boron compounds in treatment of glioblastoma is being actively investigated, but the majority of such studies is focused on the synthesis of boron compounds as sensitizers to Boron Neutron Capture Therapy (BNCT). Nonetheless, the translational functionality of boron compounds is not limited to BNCT as many boron compounds possess direct tumoricidal activity and there is substantial evidence that certain boron compounds can cross the blood-brain barrier. Moreover, boron-containing compounds interfere with several tumorigenic pathways including intratumoral IGF-I levels, molybdenum Fe–S containing flavin hydroxylases, glycolysis, Transient Receptor Potential (TRP) and Store Operated Calcium Entry (SOCE) channels. Conclusions: Boron compounds deserve to be studied further in treatment of systemic cancers and glioblastoma due to their versatile antineoplastic functions. [ABSTRACT FROM AUTHOR]

Boron suboxide (B6O)−based materials have shown good properties which make them good candidates for cutting tool and other applications where abrasive wear resistance is important. The objective of this study was to optimize the production of B6O at ambient pressure by varying reaction temperature and time. B6O powders were produced from the reaction between boric acid and amorphous boron powders at the reaction temperatures between 300°C and 1400°C for 6 h. The powders produced were characterized in terms of particle size, phase analysis and composition, product yield, as well as morphology. Increase in temperature increased both the yield as well as the particle size of the produced powders. X-ray diffraction (XRD) pattern obtained also showed improved crystallinity of the produced powder as the temperature increases. Scanning electron microscopy (SEM) images of the synthesized powder at higher temperature clearly showed improved crystallinity (star-like crystals) as the reaction temperature was increased. The B6O powders synthesized at 1300°C for 6 h had the optimum yield of over 95%. [ABSTRACT FROM PUBLISHER]

The dissociation of O2and HO2are important reactions that occur at the cathode of fuel cells and require catalysts to proceed. There is a need to replace the presently used platinum catalyst with less expensive materials. Modelling has been used to identify potential two-dimensional catalysts such as boron- and nitrogen-doped graphene. Here, the possibility of boron nitride nano-ribbons and nano-tubes which do not require doping are considered. Density functional calculations are used to show that O2and HO2can bond to zig–zag and armchair boron nitride nano-ribbons and nano-tubes. The bond dissociation energies (BDEs) to remove an O and an OH from O2and HO2bonded to the boron nitride ribbons and tubes are calculated and are a measure of the catalytic effectiveness of the boron nitride structures. The results show that both the zig–zag and armchair boron nitride ribbons could be a catalyst for HO2dissociation but not O2dissociation. However, zig–zag boron nitride nano-tubes are shown not to be effective catalysts for the dissociation of O2or HO2.An armchair boron nitride nano-tube is shown to have a very low BDEs to remove OH from HO2bonded to it and could be an affective catalyst. [ABSTRACT FROM PUBLISHER]

A novel polyhedral oligomeric silsesquioxane containing phosphorus and boron (PB-POSS) was synthesized. The resulting PB-POSS and multiwalled carbon nanotubes (MWCNTs) were incorporated into an epoxy resin (EP) to prepare PB-POSS/MWCNTs/EP composites through a solution mixing method. The synergistic effect of MWCNTs and PB-POSS on the thermal and mechanical properties and the flame retardancy of these flame retardant composites were studied. The experimental results showed that the introduction of PB-POSS or MWCNTs further improved the LOI values of the epoxy resin, and the highest LOI value (32.8%) was obtained for the formulation containing 14.6 wt% PB-POSS and 0.4 wt% MWCNTs. In addition, the incorporation of both PB-POSS and MWCNTs significantly improved the thermal and mechanical properties of the composites. The mechanical properties of composites containing 14.7 wt% PB-POSS and 0.3 wt% MWCNTs reached the maximum. The impact strength and flexural strength increased by 42% and 7%, respectively, compared to the neat epoxy resin. Thus, a combination of PB-POSS and MWCNTs in the appropriate ratio could effectively enhance the thermal and mechanical properties and the flame retardancy of the epoxy resin matrix. [ABSTRACT FROM AUTHOR]

Redistribution of boron during the silicon solidification refining process using an Si-Al melt has been studied by electron probe microanalysis and inductively coupled plasma mass spectrometry. The results and the effects of alloy composition, cooling rate and heating method on boron removal indicate that silicon can be purified by the segregation of boron to the α-Al component of the eutectic phase after the alloy solidification. Furthermore, use of lower cooling rate and Si-Al alloy with low Si content shows enhanced boron redistribution. The lowest refining ratio (0·17) and the highest removal fraction of boron (74·3%) were achieved in 22·8 at-%Si-Al alloy at a cooling rate of 3 K min−1. Induction heating was used to obtain agglomerated Si plates and also recycled ∼73·9% (by area) of byproduct (i.e. Si-Al alloy) from 35·4 at-%Si-Al alloy. [ABSTRACT FROM AUTHOR]