Laminar motion of the incompressible fluids in self-acting thrust bearings with spiral grooves.

We analyze the laminar motion of incompressible fluids in self-acting thrust bearings with spiral grooves with inner or external pumping. The purpose of the study is to find some mathematical relations useful to approach the theoretical functionality of these bearings having magnetic controllable fluids as incompressible fluids, in the presence of a controllable magnetic field. This theoretical study approaches the permanent motion regime.

Pseudo extra reflection conditions.

The extra reflection conditions as given in Volume A of International Tables for Crystallography may not be rigorously fulfilled if the thermal vibrations and positional or static disorder of the atoms are not isotropic. Although small in most cases, the intensities of reflections violating the extra reflection conditions can become measurable for large thermal and positional anisotropy. It would be useful to have an inventory of these `pseudo extra reflection conditions' for all space groups in the early stage of structure investigation.

Superparamagnetic hybrid micelles, based on iron oxide nanoparticles and well-defined diblock copolymers possessing beta-ketoester functionalities.

The quality of surface coating of magnetic nanoparticles destined as nanoprobes in clinical applications is of utmost significance for their colloidal stability and biocompatibility. A novel approach for the fabrication of such a coating involves the synthesis of well-defined diblock copolymers based on 2-(acetoacetoxy)ethyl methacrylate (chelating) and poly(ethylene glycol)methyl ether methacrylate (water-soluble, thermoresponsive), prepared by reversible addition-fragmentation chain transfer polymerization. Fabrication of magneto-responsive micelles was accomplished via chemical coprecipitation of Fe(III)/Fe(II) in the presence of diblock copolymers.