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Worldwide production capacities of carbon‐based chemicals and associated products are steadily increasing. At the same time the reduction of greenhouse gas emissions such as carbon dioxide is of paramount importance in order to mitigate the anthropogenic impact of climate change. In Carbon2Chem® a cross industrial network develops concepts towards the utilization of steel mill gases for the sustainable production of “green” base chemicals, including methanol. This Review describes the technological challenges emerging from the use of these alternative feedstocks, specifically in the context of methanol production processes.

The frequency dependencies of the storage and loss shear moduli, G' and G", of myosin rod solutions at 1.0 and 7.0 degrees C were measured by use of the Birnboim-Schrag multiple lumped resonator apparatus in solvents with and without glycerol. The infinite dilution moduli were determined and compared with theoretical models for a rigid rod and a freely jointed trinodular rod and with an empirical model for a semiflexible rod. Only the latter could fit the data. A rotational relaxation time of 25 mus and a slowest bending time of 3.1 mus, both reduced to water at 20 degrees C, were determined from the fit. A persistence length of about 130 nm was obtained from either the bending time, the rotational relaxation time, or the intrinsic viscosity. The average thermal excursion of the end of subfragment 2 was estimated to be 26 nm, more than sufficient to span the gap between the thick and thin filaments in muscles at all sarcomere lengths. Thus, a hinge between heavy meromyosin and light meromyosin does not appear necessary for myosin-actin contact. Young's modulus of about 1 x 10(9) N/m2 also makes it unlikely that subfragment 2 can be the elastic element in the Huxley-Simmons model of muscle contraction.

SynopsisThe frequency dependences of the storage and loss shear moduli, G' and G", of pronasetreated collagen dissolved in acetate buffer at pH 4.0 were measured at 17.0"C by use of the Birnboim-Schrag multiple lumped resonator apparatus. Some of the solutions contained 70% glycerol. The infinite-dilution moduli were determined and compared with theoretical models for a rigid cylinder and a semiflexible rod. Only the latter could fit the data. A rotational time of 144 ps and a slowest flexural relaxation time of 21 p s , both reduced to water at 20°C, were determined from the fit. The intrinsic viscosity and rotational relaxation time correspond to a semiflexible rod with persistence length of about 170 nm and a Young's modulus of 4 X 1O'O dyn/cm2.

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