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The previously reported silica-grafted iridium(iii) hydride complex [IrH(O–SBA-15)(POCOP)] (2), prepared by treating [IrH2(POCOP)] (1) (POCOP is 1,3-bis((di-tert-butylphosphino)oxy)benzene) with SBA-15 (mesoporous silica), hydrogenates liquid alkenes (1-decene, trans-5-decene, cyclohexene, styrene, and 4-phenyl-1-butene) at room temperature and under 1 atm H2. Internal alkenes react at a lower rate than the terminal ones. For the sake of comparison, the hydrogenation of the same substrates was studied with the homogeneous catalyst [IrH2(POCOP)] (1). The heterogeneous catalyst 2hydrogenates 1-decene, cyclohexene, and 4-phenyl-1-butene faster than 1, whereas the opposite is true for styrene and trans-5-decene, which suggests that different active species are involved in the heterogeneous and homogeneous reactions. Catalysis by a truly heterogeneous species is supported by a series of “hot filtration tests”. NMR spectroscopic studies showed that 2does not undergo degrafting upon longer exposure to alkenes compared to ethene under hydrogenation conditions.

The association between metabolic syndrome (MS) and bone status remains controversial. We aimed to study the relationships between MS, bone mineral density (BMD), and bone metabolism in postmenopausal women.

Because of the complexity of mathematical models of induction motors, the dynamic behaviour of ordinary algorithms is poor. The field-oriented control method has numerous advantages, but requires high computing power. However, implementation of this method has recently become more justifiable as a result of the decreasing price stemming from the development of power electronic devices and microprocessor techniques. A DSP (TMS320C25) based field-orientation control system with digital current regulation of the induction motor without an external current control loop is proposed. Some aspects of the theory, computer simulations and experimental results of the proposed method are given.