Oldřich Motyka

Recycling of blast furnace sludge by briquetting with starch binder: Waste gas from thermal treatment utilizable as a fuel

Steel plants generate significant amounts of wastes such as sludge, slag, and dust. Blast furnace sludge is a fine-grained waste characterized as hazardous and affecting the environment negatively. Briquetting is one of the possible ways of recycling of this waste while the formed briquettes serve as a feed material to the blast furnace. Several binders, both organic and inorganic, had been assessed, however, only the solid product had been analysed. The aim of this study was to assess the possibilities of briquetting using commonly available laundry starch as a binder while evaluating the possible utilization of the waste gas originating from the thermal treatment of the briquettes. Briquettes (100g) were formed with the admixture of starch (UNIPRET) and their mechanical properties were analysed. Consequently, they were subjected to thermal treatment of 900, 1000 and 1100°C with retention period of 40min during which was the waste gas collected and its content analysed using gas chromatography. Dependency of the concentration of the compounds forming the waste gas on the temperature used was determined using Principal component analysis (PCA) and correlation matrix. Starch was found to be a very good binder and reduction agent, it was confirmed that metallic iron was formed during the thermal treatment. Approximately 20l of waste gas was obtained from the treatment of one briquette; main compounds were methane and hydrogen rendering the waste gas utilizable as a fuel while the greatest yield was during the lowest temperatures. Preparation of blast furnace sludge briquettes using starch as a binder and their thermal treatment represents a suitable method for recycling of this type of metallurgical waste. Moreover, the composition of the resulting gas is favourable for its use as a fuel.

Metal-based particles in human amniotic fluids of fetuses with normal karyotype and congenital malformation—a pilot study

This study explores the inorganic composition of amniotic fluid in healthy human fetuses and fetuses with congenital malformation with a special attention to presence of metal-based solid particles. Amniotic fluid originates from maternal blood and provides fetus mechanical protection and nutrients. In spite of this crucial role, the environmental impact on the composition of amniotic fluid remains poorly studied. The samples of human amniotic fluids were obtained by amniocentesis, including both healthy pregnancies and those with congenital malformations. The samples were analysed using several techniques, including Raman microspectroscopy, scanning electron microscopy with energy-dispersed spectrometry (SEM-EDS), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. Several metal-based particles containing barium, titanium, iron, and other elements were detected by SEM-EDS and Raman microspectroscopy. XRD analysis detected only sodium chloride as the main component of all amniotic fluid samples. Infrared spectroscopy detected protein-like organic components. Majority of particles were in form of agglomerates up to tens of micrometres in size, consisting of mainly submicron particles. By statistical analysis (multiple correspondence analysis), it was observed that groups of healthy and diagnosed fetuses form two separate groups and therefore, qualitative differences in chemical composition may have distinct biological impact. Overall, our results suggest that metal-based nanosized pollutants penetrate into the amniotic fluid and may affect human fetuses.

Implantation of posterior chamber phakic intraocular lens for myopia and hyperopia - long-term clinical outcomes

PURPOSE To evaluate long-term refractive outcomes of implantable collamer lens (ICL) implantation and late postoperative complications. METHODS We assessed outcomes of patients who underwent ICL implantation (type ICM V4 for myopia, ICH V3 for hyperopia, TICM V4 for astigmatism) in our department between 1998 and 2013. It comprised 62 eyes (40 myopic and 22 hyperopic). The average follow-up period was 10.5 years. We evaluated: uncorrected and best-corrected visual acuity (UCVA and BCVA), spherical equivalent (SE), ICL vault, endothelial cell density and late postoperative complications. RESULTS In myopes, the average UCVA was 1.0±0.37 and BCVA 1.18±0.38, in hyperopes 0.78±0.19 and 1.14±0.18, respectively. The average SE in myopes, whose target refraction was emmetropia, was -0.6±0.83 Dsf, in hyperopes +0.73±0.93. Central ICL vault was 206.16μm±105.94, (range 10-427) in myopes, 195.5μm±109.09, (range 20-404) in hyperopes. The most common late postoperative complication was cataract formation. Three myopic eyes (7.5%) developed symptomatic anterior subcapsular opacities with loss of at least two lines of BCVA. Cataract significantly affecting visual acuity occurred in 5 myopic eyes (12.5%) and 2 hyperopic eyes (9.09%). In these eyes, ICL removal and cataract surgery was performed. CONCLUSIONS In our experience, ICL implantation in moderate and high ametropia was effective and relatively safe. The most common late complication was cataract formation. This complication can be managed effectively surgically with good refractive outcomes without loss of BCVA.

Three-Dimensional Reconstruction of Macroscopic Features in Biological Materials

This paper covers the topic of three dimensional reconstruction of small textureless formations usually found in biological samples. Generally used reconstructing algorithms do not provide sufficient accuracy for surface analysis. In order to achieve better results, combined strategy was developed, linking stereo matching algorithms with monocular depth cues such as depth from focus and depth from illumination.

Histological analysis of retraction pocket pars tensa of tympanic membrane in children

AIMS Histological and histochemical analysis of retraction pocket of pars tensa of tympanic membrane in children. Identification of morphological abnormalities in comparison with a healthy tympanic membrane as it is described in standard textbook. Identification of signs typical for cholesteatoma and support for a retraction theory of cholesteatoma formation. STUDY DESIGN A prospective study analysing 31 samples of retraction pockets taken during surgery. DEPARTMENTS University Hospital, Childrens Medical Centre METHODS Samples of retraction pockets were processed by a standard process for light microscopy, stained by haematoxylin-eosin. Van Giesons stain was used for differential staining of collagen, Verhoeffs stain for elastic fibre tissues, Alcian blue for acidic polysaccharides and PAS (Periodic Acid Schiff) method for basement membrane polysaccharides. RESULTS The following findings were observed in the samples of retraction pockets: hyperkeratosis (100%), hypervascularisations (100%), subepithelial fragmented elastic fibres (96%), myxoid changes (87%), subepithelial inflammatory infiltration (84%), rete pegs (71%), papilomatosis (71%), intraepithelial inflammatory cellularizations, (48%), intraepithelial spongiosis (16%) and parakeratosis (3%). No basement membrane continuity interruptions were observed. Thickness of retraction pocket, thickness of epidermis, occurrence of rete pegs and frequency of fragmented elastic fibres was higher in a Grade III stage RP than Grade II stage RP (according to Charachon). CONCLUSION Morphological abnormalities in the structure of retraction pockets in comparison with a healthy tympanic membrane were described. The changes are typical for a structure of cholesteatoma (these changes are common in matrix and perimatrix), supporting retraction theory of its origin. Our observations show that it is inflammation that probably plays a key role in the pathogenesis of retraction pocket. The frequency of some of the changes increases with the stage of retraction pocket (II-III according to Charachon). Basement membrane continuity interruptions are not typical for retraction pockets.

Novel Technique of Active Biomonitoring Introduced in the Czech Republic: Bioaccumulation of Atmospheric Trace Metals in two moss species / Nová Metoda Aktivního Biomonitoringu Zavedená V České Republice: Bioakumulace Stopových Kovů V Atmosféře U Dvou Druhů Mechů

Abstract A biomonitoring technique never before used in the Czech Republic was used to test its validity and applicability in the region of Ostrava that is eminently affected by industry. Transplants of two moss species Hylocomium splendens and Pleurozium schreberi were exposed to atmospheric pollution using the technique of an “irrigated moss bag” placed at a height of both 1 m and 2 m above ground. The samples were then analysed for concentration levels of trace elements Al, As, Cd, Cr, Cu, Fe, Hg, Pb, V and Zn. The patterns of bioaccumulation in general show that Hylocomium splendens is more suitable for monitoring purposes and that 2 m height above ground of transplants should be preferred. Abstrakt Za účelem validace byla pro biomonitoring v průmyslem ovlivněném regionu Ostravska použita metoda, která dosud v České republice nebyla aplikována. Transplantáty dvou druhů mechů Hylocomium splendens a Pleurozium schreberi byly vystaveny atmosférickému znečištění pomocí metody “irrigated moss bag” ve výšce jak 1 m, tak 2 m nad zemí. Vzorky byly poté analyzovány za účelem zjištění koncentrace stopových prvků Al, As, Cd, Cr, Cu, Fe, Hg, Pb, V a Zn. Celkový průběh bioakumulace ukazuje, že je Hylocomium splendens pro biomonitoring vhodnější, stejně tak jako výška 2 m nad zemí.