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Encrustation of the ureteral double-J Stents made of styrene/ethylene/butylene and polyurethane before and after implantation

Haliński Adam, Pasik Kalila, Haliński Andrzej, Haliński Paweł, Trinchieri Alberto, Buchholz Noor, Arkusz Katarzyna

Acta of Bioengineering and Biomechanics

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2022

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Vol. 24, no. 2

109--117

EN

The aim of this study was to determine the affinity to crystal, calculi and biofilm deposition on ureteral double-J stents (DJ stents) after ureterorenoscopic–lithotripsy procedure (URS-L). The analysis was performed in two aspects: to determine which material used for fabricating ureteral stents promotes encrustation and which part of the DJ stents is the most vulnerable for blockage. Methods: One hundred and twenty patients with an indwelling DJ stent duration between 7 and 78 days were included in this study. The encrustation of DJ stents was characterized by scanning electron microscopy (SEM), and the mechanical properties of DJ stents were examined using the standard MTS Micro Bionix tensile test. Results: This study showed that polyurethane catheters have a much higher affinity for encrustation than styrene/ethylene/butylene block copolymer. Obtained results indicated the proximal (renal pelvis) and distal (urinary bladder) part is the most susceptible to post-URS-L fragments and urea salt deposition. Both the DJ ureteral stents’ outer and inner surfaces were completely covered even after 7 days of implantation. Conclusions: Performed analysis pointed out that polyurethane DJ stents have a much higher affinity for encrustation of calculi and NaCl crystals compared to the silicone-based copolymer. The surface of the ureteral stents needs improvement to minimize salt and kidney stone deposition, causing pre-biofilm formation and the occurrence of defects and cracks.

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Analysis of the Variability of the Composition of Sewage Sludge Before and After Drying Treatment – SEM Studies

Kiper Justyna, Głowacka Anna, Rucińska Teresa

Journal of Ecological Engineering

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2019

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Vol. 20, nr 7

45--52

EN

The aim of the study was to determine the physical and chemical properties of the sewage sludge from “Pomorzany” and “Zdroje” municipal wastewater treatment plants located in Szczecin, Poland. The paper presents the outcomes of SEM observation of dried and stabilized sewage sludge. The research on the obtained materials was conducted using reference methods; the images from a scanning electron microscope were used. The amount of sewage sludge produced with the methods of its management was presented. The technology of sludge management is based on its dehydration up to dry weight content of roughly 20% and then drying in contact dryers up to 90–92% dry weight, separately in both plants. Dried sewage sludge is subsequently burned in mechanical grid boilers at “Pomorzany” WWTP. The analyzed materials were characterized by the pH of 7.90–8.42, dry mass and average organic matter content were 18.949% and 68.903%, respectively. The elements identified in the largest amount on the surface of analyzed materials included calcium, iron, phosphorus, sulphur and silicon. The amount of phosphorus ranging from 1.82 to 3.44% indicates the possibility of using sewage sludge as organic fertilizer product or an alternative source of phosphorus.

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Rare calciphilous diatoms from the genus Gomphonema (Bacillariophyta) in lotic waters of SE Poland

Noga T., Poradowska A., Peszek Ł., Rybak M.

Oceanological and Hydrobiological Studies

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2018

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Vol. 47, No. 1

27--40

EN

The aim of this work was to present a morphological description and ecological characteristics of a rare species from the Gomphonema genus, occurring in calcium-rich waters, along with its new occurrence sites. The research was carried out in flowing waters of mountain and sub-mountain streams and rivers in Poland: the Wołosaty, the Wisłoka, the San and their tributaries. The occurrence of many rare and new to Polish flora species from the genus Gomphonema was recorded: G. cuneolus E. Reichardt, G. drutelingense E. Reichardt, G. innocens E. Reichardt,G. lateripunctatum E. Reichardt & Lange-Bertalot, G. lippertii E. Reichardt & Lange-Bertalot and G. calcifugum Lange-Bertalot & E. Reichardt. These species occur mostly in alkaline or close-to-neutral waters with medium or low electrolytic conductivity (78–530 μS cm-1), low nutrient content and medium-to-high calcium ion content (12.4–76.4 mg l-1). Despite the rare occurrence in other parts of the world, the studied Gomphonema species has found favorable conditions in unpolluted and calcium-rich stream beds with flysch strata. The literature data define G. calcifugum as a non-calciphilous species, but this study shows that it can develop in a wide pH range and in calcium-rich waters.

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How to prepare bacteria with adsorbed nanoparticles for SEM and TEM observations

Pajerski W., Golda-Cepa M., Jarosz M., Indyka P., Pawlyta M., Kotarba A.

Engineering of Biomaterials

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2018

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Vol. 21, no. 148

67

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Morphology of Reimeria ovata (Hust.) Levkov & Ector in comparison with similar Reimeria species

Noga T., Stanek-Tarkowska J., Rybak M., Kochman-Kędziora N.

Oceanological and Hydrobiological Studies

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2017

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Vol. 46, No. 1

123--131

EN

Reimeria ovata (Hust.) Levkov & Ector was found during field research conducted from 2013 to 2015 on the Wołosaty stream and its selected tributaries. Valves measured in the studied material are narrower than valves described in the currently available literature and have more striae per 10 µm. Specimens of R. ovata observed under a light microscope were morphologically very similar to those of R. sinuata, particularly in the case of small individuals. The precise distinction between these two species was only possible under SEM. R. ovata has been found in cold, oligotrophic waters, highly saturated with oxygen, with alkaline or circumneutral pH, but never in large numbers. The aim of this work was to identify the new locations of R. ovata and to determine morphological and ecological characteristics of this species.

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Comparison of corrosion resistance in physiological saline solution of two austenitic stainless steels – 316LV and REX734

Romańczuk E., Oksiuta Z.

Acta Mechanica et Automatica

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2017

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Vol. 11, no. 2

91--95

EN

In this work two austenitic stainless steels, REX734 and 316LV were tested in terms of their microstructure and corrosion properties. The REX734 is a newer generation stainless steel, with modified chemical composition, in comparison to the 316LV grade. Potentiodynamic study of corrosion resistance was conducted in physiological saline solution (0.9% NaCl solution). In spite of the similarities of microstructure, grain size and phase structure in both materials, the corrosion tests revealed that the REX734, with lower nickel and higher nitrogen content, had better corrosion resistance than 316LV. Repassivation potential in the REX734 was almost six times higher than for the 316LV steel. Superior corrosion resistance of the REX734 steel was also confirmed by surface observations of both materials, since bigger and more densely distributed pits were detected in 316LV alloy.

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Degradation of Creep Resistant Ni - alloy During Aging at Elevated Temperature Part II: Structure Investigations

Kaczorowski M., Skoczylas P., Krzyńska A.

Archives of Foundry Engineering

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2015

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Vol. 15, iss. 4

45--50

EN

The results of structure observations of Ni base superalloy subjected to long-term influence of high pressure hydrogen atmosphere at 750K and 850K are presented. The structure investigation were carried out using conventional light-, scanning- (SEM) and transmission electron microscopy (TEM). The results presented here are supplementary to the mechanical studies given in part I of this investigations. The results of study concerning mechanical properties degradation and structure observations show that the differences in mechanical properties of alloy subjected different temperature are caused by more advanced processes of structure degradation during long-term aging at 850K, compare to that at 750K. Higher service temperature leads to formation of large precipitates of δ phase. The nucleation and growth of needle- and/or plate-like, relative large delta precipitates proceed probably at expense strengthening γ" phases. Moreover, it can't be excluded that the least stable γ" phase is replaced with more stable γ' precipitates. TEM observations have disclosed differences in dislocation structure of alloy aged at 750K and 850K. The dislocation observed in alloy subjected to 750K are were seldom observed only, while in that serviced at high stress and 850K dislocation array and dislocation cell structure was typical.