The existence of long-lived nuclear spin states in four-spin systems is explored by solution-state NMR experiments. Long-lived states are proved to exist in three different natural product molecules, each containing either a AA'BB' or a AA'XX' proton spin system. The measured state lifetimes are between four and eight times the spin-lattice relaxation time constants.

Casting is considered as a major manufacturing process. Thermal analysis of a solidifying medium is of great importance for appropriate design of casting processes. The conventional governing equation of a solidifying medium is based on the Fourier heat conduction law, which does not account for the phase-lag between the heat flux and the temperature gradient. In this paper, the concept of phas...

A scaling theory is applied in order to calculate the temperature dependence of the staggered magnetic susceptibility associated with the anti-ferromagnetism observed in high-temperature superconductors. In a logarithmic approximation, only a summation of the leading square logarithmic terms are taken into account, assuming the parquet approximation. We show that scaling theory can be applied t...

2 Although multiple pulse and multi-dimensional NMR techniques permit generation of off-diagonal density matrix elements and observation of complex coherence transfer processes, eventually the density operator returns to an equilibrium state in which all coherences (off-diagonal elements of the density operator) have decayed to zero and the populations of the energy levels of the system (diagon...

A detailed analytical and numerical analysis of a recently introduced stochastic model for fluid dynamics with continuous velocities and efficient multi-particle collisions is presented. It is shown how full Galilean invariance can be achieved for arbitrary Mach numbers and how other low temperature anomalies can be removed. The relaxation towards thermal equilibrium is investigated numerically...

A new genuinely multi-dimensional relaxation scheme is proposed. Based on a new discrete velocity Boltzmann equation, which is an improvement over previously introduced relaxation systems in terms of isotropic coverage of the multi-dimensional domain by the foot of the characteristic, a finite volume method is developed in which the fluxes at the cell interfaces are evaluated in a genuinely mul...

The electro-optic and dielectric properties of ferroelectric liquid crystal-multi-wall carbon nanotube dispersions were investigated with respect to temperature and nanotube concentration. The main physical properties, such as tilt angle, spontaneous polarization, response time, viscosity, and Goldstone-mode relaxation strength and frequency were studied. While all dispersions exhibit the expec...

The choice of a suitable material model to simulate process induced distortions is important in order achieve right first time approach the design new moulds. This work investigates ability Cure Hardening Instantaneously Linear Elastic (CHILE) and linear viscoelastic predict an aerospace composite frame. models were coupled with cure kinetics chemical shrinkage capture multi-physics phenomena t...