The complexes, [Cu{EC(5)H(3)(R-3)N}](4) (E/R = Se/Me or Te/R; R = H or Me) were isolated by the reaction between CuCl and NaEC(5)H(3)(R-3)N and were characterized by elemental analyses, uv-vis and NMR ((1)H, (13)C) spectroscopy. The crystal structures of [Cu{SeC(5)H(3)(Me-3)N}](4) and [Cu(TeC(5)H(4)N)](4) revealed that the molecules are tetrameric in which each copper atom lies at the vertex of...

Three-dimensional Delaunay triangulations are the most common form of three-dimensional triangulations known, but they are not very suitable for tetrahedral nite element meshes because they tend to contain poorly-shaped sliver tetrahedra. In this paper, we present an algorithm for constructing improved-quality triangulations with respect to a tetrahedron shape measure. This algorithm uses combi...

We present an algorithm to test two tetrahedra for overlap. The algorithm is based on a dimension reduction technique that allows to apply the Separating Axis Theorem avoiding part of the computation needed to perform the Separating Axis Test. Source code is available online.

The kinetics of substitution of [Ti(ur)6]3+ by H2O and SCN¯ ion in ethanol solution have been measured spectrophotometrically by stopped-flow method. Water is a good nucleophile toward Ti(III) substrates. Even the solvent ethanol appears to be a poor ligand when compared to water. Substitution, in general follows two parallel pathways: "direct" (second order...

Three quinary polar intermetallic compounds in the (Eu(1-x)Ca(x))9In8(Ge(1-y)Sn(y))8 (x = 0.66, y = 0.03) and the (Eu(1-x)Ca(x))3In(Ge(3-y)Sn(1+y)) (x = 0.66, 0.68; y = 0.13, 0.27) phases have been synthesized using the molten In-metal flux method, and the crystal structures are characterized by powder and single-crystal X-ray diffractions. Two orthorhombic structural types can be viewed as an ...

Institute of Engineering Cybernetics Academy of Sciences of Republic Belarus Surganova 6, 220012 Minsk, Belarus {tuzikov,sheynin,vasiliev}@mpen.bas-net.by Received April 10, 2002 It is well known that such important geometric characteristics of 3D bodies as volume and orientation can be defined in terms of moments. A moment computation depends greatly on a body representation. The most popular ...

In this paper we prove that the surface of the regular truncated tetrahedron can be triangulated into 10 non-obtuse geodesic triangles, and also into 12 acute geodesic triangles. Furthermore, we show that both triangulations have minimal size.

In this paper, an adaptive attitude control algorithm is developed based on neural network for a satellite using four reaction wheels in a tetrahedron configuration. Then, an attitude control based on feedback linearization control is designed and uncertainties in the moment of inertia matrix and disturbances torque have been considered. In order to eliminate the effect of these uncertainties, ...

When various p-substituted phenols (substituent = NO2, CN, CH2OH, COCH3, COPh, COOH, F, Cl, and Br) were incubated with rat liver microsomes, the substituent was eliminated to produce hydroquinone, and the reaction was inhibited by CO and a cytochrome P450-specific inhibitor. In the case of p-cresol (substituent = CH3), p-toluquinol was formed instead of hydroquinone. Experiments using 18O2 pro...