Abstract Gilsonite has a wide variety of applications in the industry, including manufacture electrodes, paints and resins, as well production asphalt roof-waterproofing material. ash is determining parameter for its application some industries (e.g., gilsonite with content < 5% used an additive drilling fluids, resins). Due to shortage high grade (low ash) reserves, aim this study develop p...

We report on the growth mechanism of YBa2Cu3O7−x. Our study is based on the analysis of ultrathin, YBa2Cu3O7−x layers in c-axis oriented YBa2Cu3O7−x / PrBa2Cu3O7 superlattices. We have found that the release of epitaxial strain in very thin YBCO layers triggers a change in the dimensionality of the growth mode. Ultrathin, epitaxially strained, YBCO layers with thickness below 3 unit cells grow ...

We compare the roughness of minimal energy(ME) surfaces and scalar “quasi-static” fracture surfaces(SQF). Two dimensional ME and SQF surfaces have the same roughness scaling, w ∼ L (L is system size) with ζ = 2/3. The 3-d ME and SQF results at strong disorder are consistent with the randombond Ising exponent ζ(d ≥ 3) ≈ 0.21(5 − d) (d is bulk dimension). However 3-d SQF surfaces are rougher than...

We perform a comprehensive survey of the potential energy landscapes of 13-atom Morse clusters, and describe how they can be characterized and visualized. Our aim is to detail how the global features of the funnel-like surface change with the range of the potential, and to relate these changes to the dynamics of structural relaxation. We find that the landscape becomes rougher and less steep as...

Heat transfer in rough circular cylinder microfins is studied and a new analytical model is developed. Assuming Gaussian isotropic surface roughness, it is shown that both cross-sectional and surface areas ofmicrofins increase by increasing roughness. Consequently, an enhancement is observed in the heat transfer rate and thermal performance of microfins. The effect of roughness is more profound...

A method for extending atomistic computer simulations of solids beyond the nanosecond time scale was used to simulate metal crystal growth on the time scale of laboratory experiments. Transitions involving concerted motion of multiple atoms on the crystal surface are found to lead to remarkably smooth growth of pure Al(100). Cu(100) is found to grow with a rougher surface, consistent with exper...

We consider the L-critical quintic focusing nonlinear Schrödinger equation (NLS) on R. It is well known that H solutions of the aforementioned equation blow-up in finite time. In higher dimensions, for H spherically symmetric blow-up solutions of the L-critical focusing NLS, there is a minimal amount of concentration of the L-norm (the mass of the ground state) at the origin. In this paper we p...

© 2000 The International Bank for Reconstruction and Development / THE WORLD BANK Lant Pritchett is with the East Asia and the Pacific Country Units at the World Bank. His e-mail address is [email protected]. The author would like to thank William Easterly, Ross Levine, Deon Filmer, Dani Rodrik, and the participants at seminars at the World Bank and the Massachusetts Institute of Technol...

The use of magnesium alloys is limited due to their susceptibility to corrosion although they have many attractive physical and mechanical properties. To increase mechanical and corrosion properties of these alloys, many deposition method and coating types are used. Electroless Ni–B coatings have received considerable interest recently due to its unique properties such as cost-effectiveness, th...

Recently ([21]), a new meshfree approximation method for Darcy’s problem has been introduced and analyzed. This method is based on a symmetric collocation approach using radial basis functions producing solutions with an analytically divergence-free velocity part. However, the error analysis provided in [21] works only for smooth solutions, where the smoothness is intrinsically linked to the sm...