In this work, new polyoxymethylene (POM)/hydroxyapatite (HAp) nanocomposites for long‐term bone implants have been obtained via extrusion and injection molding processes and characterized by differential scanning calorimetry (DSC), temperature‐modulated DSC (TMDSC), scanning electron microscopy (SEM), transmission electron microscopy (TEM), wide‐angle X‐ray diffraction (WAXD), Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG), and tensile mechanical and in vitro stability tests. Based on the DSC results, it was found that the degree of crystallinity increases for POM/0.5% HAp sample and decreases for POM/1.0% HAp and POM/2.5% HAp. SEM and TEM observations for POM/HAp nanocomposites indicated that the dispersion of HAp in the polymer matrix was uniform and the diameter of the HAp particles was less than 100 nm for most of them. Young's modulus increases with increasing HAp concentration, whereby elongation at break decreases. On the contrary, HAp concentration does not have a significant influence on the tensile strength. TG results show that for POM/0.5% HAp, POM/1.0% HAp, and POM/2.5% HAp, thermal stability slightly increases in comparison to pure POM, whereas for POM/5.0 HAp and POM/10.0% HAp, lower thermal stability was observed. In vitro data reveal that with an increase of HAp content, bioactivity of nanocomposites increases; a good in vitro chemical stability of POM and POM nanocomposites was confirmed. Copyright © 2011 John Wiley & Sons, Ltd.

The results of the studies on the synthesis, mechanical and thermal properties of polypropylene composites with various amount of halloysite filler are presented. Halloysite (HNT) belongs to the silica type characterized by a two-layer 1:1 structure. This work was aimed to develop a method for the modification of halloysite in its prime use as a filler for polypropylene by extrusion. The composites contain 1, 3, 5 and 7 wt.% of HNT. The degree of crystallinity of the composites decrease with increasing halloysite content. The results confirm the expectations that composites of interesting physicochemical, mechanical and thermal properties can be obtained. The mechanical properties studied show that the filler modification method used leads to the synthesis of polymer composites of improved thermal and mechanical properties.

The article refers to a non-classic model of an organization, which is a hypertext organization. The hypertext organization combines a highly hierarchical organizational structure with the flexibility of management solutions supporting the conversion of various types of knowledge. It is considered to be a one of the most adequate models for managing the organization of the 21st century. Thereby, it contains in its assumptions solutions corresponding to challenges of the knowledge age and management of knowledge workers. The hypertext organization is able to successfully meet difficult requirements of the modern market and needs of an evolving society of different generations. It is important to show that the hypertext organization, being able to switch between “contexts” of knowledge creation, enables an efficient response to changing internal and external knowledge requirements. The article is a theoretical discourse, the aim of which is to outline a concise characterization of a new solution in the subject of organizational structures, present the essence of hypertext solutions and show chances and capabilities of knowledge management in such organizations, that finally allow a transformation of institutions in intelligent organizations. Special attention will be paid to strongly hierarchical organizations such as uniformed services, especially the armed forces.

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Shaping the image of uniformed services is related to many conditions, including historical ones, stereotypes, or the opinion of circles that have often come into conflict with, for example, the Police. Thus, it is more difficult for uniformed services than for enterprises to influence their image in the eyes of society, the more so as the media often create specific messages through their reports. The image of each organization is a component of intellectual capital, which is a consolidated intangible resource. Managing this comprehensive intangible resource will result in, among other things, higher efficiency, increased innovation and creativity, greater involvement of staff, and the desire to self-improve, which will lead to shaping a better and better image. The study aims to present results of research on the image as an intangible resource as an intellectual capital element, and preliminary research on perceiving the image of the Police and the Armed Forces of the Republic of Poland. They were carried out on a selected sample of young people.