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Boron forms various compounds with metal atoms occupying voids in the boron framework. As a synthesis method it has been found that the addition of small amounts of third elements like carbon, nitrogen, and silicon can result in the formation of novel and varied rare earth boron cluster structures. A wide variation of 1D, 2D, and 3D magnetic behavior with unexpectedly strong magnetic interactions has been discovered in rare earth boron icosahedra compounds which are magnetically dilute, f-electron insulators. As an intriguing phenomenon, the B12 icosahedra cluster, which is a building block of the structure, has been indicated to function as a novel mediator of magnetic interaction. These phenomena are borides. Attractive high temperature thermoelectric properties are also emerging in borides. Attractive high temperature thermoelectric properties are also emerging in this group of compounds, which is striking due to the great potential of utilizing waste heat. Recent developments on the long awaited n-type counterpart to boron carbide, the homologous series of RE-B-C(N) compounds, REB17CN, REB22C2N, and REB28.5C4, will be presented together with those of p-type REB44Si2. General new ways to improve the thermoelectric properties are also discussed. For example, seeding with highly electrically conductive metallic borides like REB4 and REB6 is found to be a way to significantly increase the thermoelectric figure of merit. Electric resistivity significantly decreases while Seebeck coefficients and thermal conductivity are not sizably affected. [ABSTRACT FROM AUTHOR]

In this paper, we introduce the prototype of a low cost haptically augmented stylus for pen computing on touch screens. The stylus supports human-computer interaction through a dynamic haptic feedback. This reflective feedback is generated by a magnetically operated brake system. The feedback actuator is integrated in the stylus. Therefore, the pen supports the use of multiple styli on a single touch screen. The pen provides a broad scale of feedback – especially for the display of haptic surface cues. Hence, it is predestined for stroke gestures, as they are commonly used in crossing-based pen interfaces. [ABSTRACT FROM AUTHOR]

Samples of titanium carbide (TiCx) in a carbon matrix have been prepared by the nonhydrolytic sol-gel process. The nanocomposite powder samples containing one the TiCx of average size ca. 30 nm encapsulated in carbon cages of 3 wt.% and other the TiCx in carbon matrix (ca. 10 wt.%) have been obtained. The temperature dependence of the EPR spectra of titanium carbide has shown coexistence of two different paramagnetic centers, one arising from conducting electrons and the other from trivalent titanium ion complexes. Comparison with a similar titanium nitride (TiNx) is made, where no EPR spectra of trivalent titanium ions exist. The titanium nitride has shown only the EPR spectra arising from magnetic localized centers and not from trivalent titanium ion complexes. The magnetic ordering and superconducting states are observed in titanium carbide in the low temperature region, while in titanium nitride only the later state is recorded. The titanium nitride is a good conducting material while the titanium carbide shows an extraordinary behaviour, especially in the higher temperature region where a sharp jump in conductivity is recorded about 250 K. It is suggested that the disorder-order processes are more intense in the nonstoichiometric titanium carbide. [ABSTRACT FROM AUTHOR]

Detailed gravity and magnetic maps reveal the regional structural features of the central Mediterranean Sea. These maps incorporate substantial proprietary databases as well as data exchanged with other companies or agencies. They include comprehensive regional Bouguer anomalies, residual magnetic field and its reduction to the pole. In addition to the gravity and magnetic products, a topographic map was created by merging several data sets, including a DTM (digital terrain model) acquired by Getech (Geophysical Exploration Technology of Leeds -- UK), together with satellite, land and marine data. This topographic map was implemented in interpretation of the gravity data. [ABSTRACT FROM AUTHOR]