this study is concerned with the prediction of particles’ velocity in a dilute turbulent gas-solidboundary layer flow using a fully eulerian two-fluid model. the closures required for equationsdescribing the particulate phase are derived from the kinetic theory of granular flows. gas phaseturbulence is modeled by one-equation model and solid phase turbulence by mlh theory. resultsof one-way and...

A new sensitive and selective spectrophotometric method for the determination of iron using a PVC membrane containing bathophenanthroline and dioctylphethalate as the solid phase extraction medium is investigated. Fe(II) in an aqueous sample solution is trapped on the membrane with an anion species, picrate ion and forms a complex with bathophenanthroline. The absorbance of the red-orange m...

in this research, mechanical alloying was used to produce ti-50al, ti-45al-5cr and ti-45al-5w (at%) alloys. the effect of ternary addition (cr and w) on microstructure and production efficiency of tial alloy were investigated. alloying was performed in a planetary mill and the milling time varying from 5 to 70h. the structural evaluation in these powders was done by x-ray diffraction (xrd) tech...

Precipitation ofsolid paraffins is one ofthe most common problems in the oil industry, imposing high operating costs. There have been a great many efforts for the prediction <span style="font-size: 10p...

Isocyanates 7 were formed from monoprotected diamines 3 or 6, which in turn can be easily prepared from commercially available N-BOCor N-FMOC-protected amino acid derivatives. Isocyanates 7, formed in situ, could be coupled directly to a solid support functionalized with amine groups or to amino acids anchored on resins using CH2Cl2 as solvent and an 11 h coupling time at 25 °C. Such couplings ...

5 2.

The chemical synthesis of peptides or small proteins is often an important step in many research projects and has stimulated the development of numerous chemical methodologies. The aim of this review is to give a substantial overview of the solid phase methods developed for the production or purification of polypeptides. The solid phase peptide synthesis (SPPS) technique has facilitated conside...

The main objective of this contribution is to describe the fundamental concepts associated with solid-phase microextraction (SPME). Theory provides insight when developing SPME methods and identifies parameters for rigorous control and optimization. A mathematical model has been developed to understand the principal processes of SPME by applying basic fundamental principles of thermodynamics an...

Berrueta LA, Gallo B and Vicente F (1995) A review of solid-phase extraction: basic principles and new developments. Chromatographia 40(7/8): 474}483. Guzman NA, Park SS, Schaufelberger D et al. (1997) Review: new approaches in clinical chemistry: on-line analyte concentration and microreaction capillary electrophoresis for the determination of drugs, metabolic intermediates and biopolymers in ...