Free cooling of granular materials is analyzed on the basis of a pseudoLiouville operator. Exchange of translational and rotational energy requires surface roughness for spherical grains, but occurs for non-spherical grains, like needles, even if they are perfectly smooth. Based on the assumption of a homogeneous cooling state, we derive an approximate analytical theory. It predicts that coolin...

We have developed a quantitative and relatively model-independent measure of lipid fluidity using EPR and have applied this method to compare the temperature dependence of lipid hydrocarbon chain fluidity, overall protein rotational mobility, and the calcium-dependent enzymatic activity of the Ca-ATPase in sarcoplasmic reticulum. We define membrane lipid fluidity to be T/eta, where eta is the v...

This paper describes an approach for making use of the components of the experimentally determined rotational diffusion tensor derived from NMR relaxation measurements in macromolecular structure determination. The parameters of the rotational diffusion tensor describe the shape and size of the macromolecule or macromolecular complex, and are therefore complementary to traditional NMR restraint...

Nowadays the position of the renewable energy is so important because of the environment pollution and the limitation of fossil fuels in the world. Energy can be generated more and more by the renewable sources, but the fossil fuels are non-renewable. One of the most important renewable sources is the wind energy. The wind energy is an appropriate alternative source of fossil fuel. The replacem...

Black hole-torus powered by the spin energy of a Kerr black hole. Equivalence in poloidal topology to pulsar magnetospheres suggests a long-lived state in suspended accretion when the black hole spins rapidly. The rotational energy is released in several channels: baryon-poor jets along open flux tubes extending from the horizon to infinity, gravitational radiation from the torus, winds and, co...

We shall study a special class of systems called dissipative systems. Intuitively, we can think of systems interacting with the surrounding via some input / output ports, exchanging power with the surrounding, storing some energy and dissipating some. For example, electrical systems exchange power with the surrounding via an inner product between the current and voltage, i.e., Pe = v i. Energy ...