The paper presents a method of modifying polyacrylonitrile (PAN) fibers using polyaniline (PANI). The PAN fibers were doped with polyaniline that was obtained in two different ways. The first consisted of doping a spinning solution with polyaniline that was synthesized in an aqueous solution (PAN/PANI blended), and the second involved the synthesis of polyaniline directly in the spinning solution (PAN/PANI in situ). The obtained fibers were characterized by the methods: X-ray powder diffraction (XRD), scanning electron microscope (SEM), fourier-transform infrared spectroscopy (FTIR), thermogravimetry (TG) and differential scanning calorimetry (DSC). Analysis of the results showed strong interactions between the nitrile groups of polyacrylonitrile and polyaniline in the PAN/PANI in situ fibers. The results of mechanical strength tests indicated that the performance of the PAN/PANI mixture significantly improved the mechanical parameters of polyaniline, although these fibers had a weaker strength than the unmodified PAN fibers. The fibers obtained as a result of the addition of PANI to PAN were dielectric, whereas the PANI-synthesized in situ were characterized by a mass-specific resistance of 5.47 kΩg/cm².

In this article, a simple dead-beat control for an electromagnetic servo is proposed. An electromagnetic servo is identified as a third-order linear continuous-time plant. A method of a dead-beat control of its discrete equivalence is proposed. A variable-order, fractional-order backward difference is used in the control algorithm.

The inkjet-printing technique was used to deposit a commercial silver nanoparticle ink in order to fabricate the electro-conductive layers directly on the different natural, synthetic, blend and mineral textile fabric surfaces with simultaneous sintering at 130℃ during printing process. This modification eliminated the necessity of sintering of silver prints in a box oven and significantly minimised ink spreading over the fabric. The silver nanoink used was characterised by means of ultraviolet-visible spectrometry, dynamic light scattering and transmission electron microscopy. The changes in surface resistance of the fabrics with the silver-deposited layers have been measured by means of the four-probe method. The morphology of the silver layers has been observed by optical microscopy and scanning electron microscopy. The conducting layers were also characterised chemically by means of energy dispersive spectroscopy. The changes in surface resistance of the silver inkjet-printed textiles were evaluated in the bending tests and after the rubbing, washing and dry-cleaning processes. The obtained results proved that the proposed shape-programmed inkjet-printing method was very simple, giving an excellent adhesion of the inkjet-printed silver layers to the substrates and ensuring a very low surface resistance. The studies have confirmed the usefulness of the ink applied for inkjet printing of silver electrodes and their good tolerance to bending, washing and dry-cleaning processes.