Microwave spectroscopy is a very accurate method to determine the potential barrier restricting the rotation of a methyl group [1 —3] . The finite barrier hindering internal rotation normally splits each rotational line into two components. This splitting depends strongly on the height of the barrier. Generally the barrier is determined from the splittings in the ground torsional state. But for...

Flexible PV modules are manufactured using roll to roll (R2R) technology. These modules require a flexible barrier material to prevent water vapor ingress. The basic methodology to produce such barriers is to combine oxide layer (e.g. AlOx) coating with suitable polymer substrates. However, micro and nano scale defects can appear at any stage of the coating process thus affecting the module eff...

In simulations of the two-dimensional Ising model, we examine heterogeneous nucleation induced by a small impurity consisting of a line of l fixed spins. As l increases, we identify a limit of stability beyond which the metastable phase is not defined. We evaluate the free energy barrier for nucleation of the stable phase and show that, contrary to expectation, the barrier does not vanish on ap...

If seven maids with seven mops Swept it for half a year. Do you suppose,” the Walrus said, “That they could get it clear?” “I doubt it,” said the Carpenter, And shed a bitter tear. We consider the problem of decontaminating (cleaning) the interior of a planar shape by sweeping it with barrier curves. The contaminant is assumed to instantly travel any path not blocked by a barrier. We show that ...

We present a time dependent theory of laser catalysis, a process in which a strong light source is used to aaect tunneling through a potential barrier by inducing a transient electronic excitation to a bound state. We have performed detailed calculations of pulsed laser catalysis on a one-dimensional Eckart potential as a function of the collision energy and the laser's central-frequency. As in...

Biomimetic membranes in contact with a planar substrate or a second membrane are studied theoretically. The membranes contain specific adhesion molecules (stickers) which are attracted by the second surface. In the absence of stickers, the trans-interaction between the membrane and the second surface is assumed to be repulsive at short separations. It is shown that the interplay of specific att...

a method is described by which it is possible to determine the high barrier to ring inversion and hindered rotation by neat racemization of optically active compounds when the racemization is caused by ring inversion or hindered rotation. the method is based preparation of sufficiently pure enantiomers, mainly by chromatography on swollen microcrystalline triacetylcellulose (tac). by this techn...

In this paper, the effects of horizontal stress and dimensions of barrier pillars on the stability of drifts hr been investigated. An elastoplastic hybrid finite/boundary element program has been used. A plastic analysis of stresses in barrier pillars above the drifts in one of the underground coal mines with inclined seams is examined. Computed stresses and safety factor controur lines around ...

Background Despite successful cloning of many mammalian species, the cloning efficiency is extremely low compared to that of IVF raising the possibility of the existence of epigenetic barrier preventing successful cloning. MaterialsAndMethods Using comparative transcriptome analysis comparing transcriptomes of IVF and SCNT embryos and that of donor cells, we identified epigenetic barrier and fi...