Commercial C(18) columns packed with superficially porous particles of different sizes and shell thicknesses (Ascentis Express, Kinetex, and Poroshell 120) or sub-2-μm totally porous particles (Acquity BEH) were systematically compared using a small molecule mixture and a complex natural product mixture as text probes. Significant efficiency loss was observed on 2.1-mm id columns even with a l...

Applying the pulsed field-gradient nuclear magnetic resonance (PFG-NMR) technique, timedependent self-diffusion coefficients, ) (∆ D 0 D , of water were measured in anhydrite cemented sandstones, in order to determine geometrical parameters of the pore space. As a first approach the Padé approximation, combining the short-time behaviour with the long-time asymptotic value of (where is the bulk ...

It was demonstrated that the peak parking-moment analysis (PP-MA) method could be used as an alternative for the measurement of pore diffusivity (D(p)) in porous packing materials for HPLC. The value of D(p) of uracil was measured by the PP-MA method under non-retained conditions in the RPLC systems using C18-silica gel particles and C18-silica monolith as the stationary phase and 70 vol% metha...

We extend the concept of packing dimension profiles, due to Falconer and Howroyd (1997) and Howroyd (2001), and use our extension in order to determine the packing dimension of an arbitrary image of a general Lévy process.

An equivalent definition of packing dimension is given for a set in d-dimensional Euclidean space by using its component sets as packings. It is applied to determine the packing dimensions of a class of subsets with prescribed relative group frequencies. c © 2008 Elsevier Ltd. All rights reserved.

Let X = {X(t), t ∈ RN} be a Gaussian random field with values in Rd defined by X(t) = ( X1(t), . . . , Xd(t) ) , ∀ t ∈ R , where X1, . . . , Xd are independent copies of a centered real-valued Gaussian random field X0. We consider the case when X0 is anisotropic and study the packing dimension of the range X(E), where E ⊆ RN is a Borel set. For this purpose we extend the original notion of pack...

The process of bone healing requires the restoration of both anatomy and physiology, and there is a recognized need for innovative biomaterials that facilitate remodeling throughout this complex process. While porous scaffolds with a high degree of interconnectivity are known to accelerate cellular infiltration and new bone formation, the presence of pores significantly diminishes the initial m...

A systematic study has been performed employing the use of a cationic surfactant didodecyldimethylammonium bromide (DDAB), an anionic surfactant sodium lignosulfonate (SLS) and water for Enhanced Oil Recovery (EOR) from the underground porous media of the depleting oil field of Naharkotiya, Duliajan, in the Upper Assam basin, India. The strong electrostatic interaction between the oppositely ch...

Non-porous reversed-phase (NP-RP) HPLC has been used to rapidly generate protein profiles of whole cell lysates of human breast cancer cell lines. The non-porous packing material used was silica coated with C18, which provided rapid separation with high collection efficiency of proteins from cell lysates. This method was used to study the differences in protein profiles among normal cells and f...

We report a three-dimensional (3D) porous carbon electrode containing both nanoscale and microscale porosity, which has been hierarchically organized to provide efficient ion and electron transport. The electrode organization is provided via the colloidal self-assembly of monodisperse starburst carbon spheres (MSCSs). The periodic close-packing of the MSCSs provides continuous pores inside the ...