The new spin cluster [MnII4MnIII3(teaH)3(tea)3](ClO4)2×3MeOH realizes a topological structure of mixed-valence manganese clusters which is especially favorable for a high-spin ground state. The magnetic properties of the spin cluster are studied numerically by exact diagonalization of the spin Hamiltonian. By magnetic susceptibility two exchange constants are found: J1/kB = − 1.28 K and J2/kB = + 4.25 K, which lead to a S = 11 high-spin ground state. Electron spin resonance (ESR) measurements at three frequencies 95, 190 and 285 GHz confirm the large spin of the ground state and reveal an Ising anisotropy of the ground state which is characterized by the spin Hamiltonian H = α(Sz)2 + β(Sz)4 with α/h.c. = − 0.08 cm−1 and β = − 2.1 × 10−4 cm−1. Ac-susceptibility shows thermally activated relaxation of the magnetization for temperatures above T = 1 K with an activation energy of ΔE/kB = − 19.5 K and a relaxation time of τ0 ≈ 10−8 s.

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A number of heterogeneously catalyzed reactions, mainly gas-phase reactions, have been performed previously at a laboratory scale and a successful proof of concept was achieved. Since the beginning of this century, there has been a shift in focus on the transfer from laboratory scale to production scale. In particular, this review deals with the technical concepts and economic aspects involved in such a shift. Heterogenously catalyzed gas-phase and liquid-phase processes are discussed separately. The preparation of wall catalysts is a key technology in both cases and is described in an additional subsection. Finally, an evaluation of the developmental status is given.

It is estimated that operating continuously on a B20 fuel containing the current allowable ASTM specification limits for metal impurities in biodiesel could result in a doubling of ash exposure relative to lube-oil derived ash. The purpose of this study was to determine if a fuel containing metals at the ASTM limits could cause adverse impacts on the performance and durability of diesel emission control systems. An accelerated durability test method was developed to determine the potential impact of these biodiesel impurities. The test program included engine testing with multiple DPF substrate types as well as DOC and SCR catalysts. The results showed no significant degradation in the thermo-mechanical properties of cordierite, aluminum titanate, or silicon carbide DPFs after exposure to 150,000 mile equivalent biodiesel ash and thermal aging. However, exposure of a cordierite DPF to 435,000 mile equivalent aging resulted in a 69% decrease in the thermal shock resistance parameter. It is estimated that the additional ash from 150,000 miles of biodiesel use would also result in a moderate increases in exhaust backpressure for a DPF. A decrease in DOC activity was seen after exposure to 150,000 mile equivalent aging, resulting in higher HC slip and a reduction in NO 2 formation. The metal-zeolite SCR catalyst experienced a slight loss in activity after exposure to 435,000 mile equivalent aging. This catalyst, placed downstream of the DPF, showed a 5% reduction in overall NOx conversion activity over the HDDT test cycle.