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1

Destruction Mechanism of Z10400 Zn-based Alloy Subjected to Cavitational Erosion

100%

Jasionowski R. , Zasada D. , Polkowski W.

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tom Vol. 13, iss. 2 spec.

48--52

EN

Z10400 zinc-based alloy has a very good casting properties and high resistance to corrosion. These two advantages make that Z10400 zinc-based alloy is commonly used for cathodic protection of hulls of ships. Cathodic anodes made of Z10400 zinc-based alloy in the propeller and flap rudder areas are also additionally exposed to the cavitation erosion. The aim of this work was to determine the cavitation erosion resistance of Z10400 zinc-based alloy, which is applied as protectors in cathodic protection of hulls of ships. The examination of cavitational erosion was carried out on a jet-impact measuring device. Study of the mechanism of the destruction of Z10400 alloy based on analysis was performed with scanning electron microscope Quanta 3d FEG and electron back scattered diffraction (EBSD) method.

2

Effect of Crystalographic Texture on Cavitation Wear Resistance of As-Cast CuZn10Alloy

100%

Polkowski W. , Jasionowski R. , Zasada D.

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nr 2

3

EBSD Strain Analysis of CuZn10 Cast Alloy During Cavitational Wear

100%

Jasionowski R. , Zasada D. , Polkowski W.

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tom Vol. 13, iss. 1 spec.

51--56

EN

Microstreams of liquid formed during the implosion of cavitation bubbles and the effects of pressure waves coming from disappearing bubbles are the main causes of damage of the washed surface, leading to loss of material (the cavitation erosion). Repeated cavitation implosions cause non-uniform stress state resulting in the strengthening of the surface layer, change of micro-geometry and surface cracks leading to detachment of the material particles. Course of cavitation erosion process depends on the effects of plastic deformation at the beginning of the destruction. The aim of this study was analysis of plastic deformation by EBSD method of CuZn10 cast alloy at the beginning of the cavitation destruction process.

4

A comparison of various imaging modes in scanning electron microscopy during evaluation of selected Si/refractory sessile drop couples after wettability tests at ultra-high temperature

88%

Polkowska A. , Warmuzek M. , Kalarus J. , Polkowski W. , Sobczak N.

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tom Vol. 57, no. 4

337--344

EN

In this work, FEI SciosTM field emission gun scanning electron microscope (FEG SEM) equipped with a unique combination of analytical and imaging detectors was utilized to examine structure and chemistry of selected Si/ refractory couples. The couples were obtained in wettability tests performed by the sessile drop method coupled with contact heating of a refractory substrate (h-BN, SiC) at ultra-high temperature (up to 1750°C). The SEM observations were carried out on top-views of the couples, in order to evaluate surface and interfacial phenomena in Si/h-BN and Si/SiC systems. A full range of available detectors (e.g. classical Everhart-Thornley detector (ETD) or advanced in-lens detectors) working under various operation modes (secondary electrons (SE), backscattered electrons (BSE), a mixed mode), were used upon analyses in order to reveal specific features of obtained structures.

5

Awareness of gastrointestinal tract malignancies among the population of Lublin province (Eastern Poland) - a cross-sectional study

75%

Barbecka M. , Kolasinska-Bzoma M. , Kolasinska-Gliwa E. , Polkowski W. , Offerhaus G. J. A. , Maciejewski R. , Sitarz R.

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nr 3

6

Bioimpedance vector pattern in women with breast cancer detected by bioelectric impedance vector analysis. Preliminary observations

75%

Malecka-Massalska T. , Chara K. , Smolen A. , Kurylcio A. , Polkowski W. , Lupa-Zatwarnicka K.

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2012

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tom 19

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nr 4

7

Wetting behavior of Si-13.5B alloy on polycrystalline h-BN-based substrates

63%

Polkowski W. , Sobczak N. , Nowak R. , Kudyba A. , Bruzda G. , Polkowska A. , Homa M. , Turalska P. , Shuleshova O. , Kaban I.

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tom Vol. 57, no. 4

321--326

EN

In this work, for the first time the results of an experimental evaluation of the high temperature behavior of molten Si-B alloy in contact with refractory materials at temperatures up to 1750°C, under static argon atmosphere (p = 850– 900 mbar), is shown. The material investigated, having a nominal chemical composition of Si-13.5B (at. %), was fabricated by using the crucible-less electric arc-melting process assisted by the levitation drop method. The wettability of the molten alloy in contact with commercial hexagonal boron nitride (h-BN) substrates was evaluated by means of especially developed sessile drop technique combined with a contact heating procedure. It was found that both couples show a lack of wettability in the whole tested temperature range (the measured contact angle was θ > 130°). The more stable behavior in contact with molten Si-13.B alloy, evidenced by higher θ values and a lack of drop vibration during the high temperature exposition, was observed for the h-BN based composite substrate.

8

Melanoma and skin cancers in psoriatic patients treated with phototherapy. Role of the p16 protein in psoriasis

63%

Szponar-Bojda A. , Pietrzak A. , Sobczynska-Tomaszewska A. , Borzecki A. , Kurylcio A. , Polkowski W. , Poluha A. , Chodorowska G.

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nr 4

9

Altered tissue electrical properties in women with breast cancer – Preliminary observations.

51%

Malecka-Massalska T. , Chara K. , Golebiowski P. , Wladysiuk M. , Smolen A. , Kurylcio A. , Zuchora B. , Zubrzycki J. , Orlowska-Kowalik G. , Lupa-Zatwarnicka K. , Polkowski W.

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nr 3

EN

Introduction and objectives: In the United States, breast cancer (BC) is the most common non-skin cancer. In Poland, it is estimated that the number of new breast cancer cases affects about 13,500 women each year. There are many methods for nutritional status assessment. One of them is bioimpedance analysis (BIA). Direct bioimpedance measures (resistance, reactance, phase angle (PA)) determined by bioelectrical impedance analysis (BIA) detectf changes in tissue electrical properties. The study was conducted to investigate whether there are any tissue electrical differences in patients with breast cancer. Materials and methods: The direct bioimpedance measures determined by bioelectrical impedance analysis (BIA) were performed on 34 patients with BC and 34 healthy volunteers. The measurements were made with ImpediMed bioimpedance analysis SFB7 BioImp v1.55 (Pinkenba Qld 4008, Australia). Results: Reactance and resistance at 50 kHz was found to be significantly greater in patients with BC than in the control group (53.59° ± 1.53 vs. 47.26° ± 1.25, respectively, p=0.0031; 603.24° ± 15.38 ohm vs. 515.87° ± 11.48 ohm, respectively, p=0.00004). Conclusion: Pre-surgical patients diagnosed with BC have altered tissue electrical properties. Further observations of a larger patient group would be valuable to calculate survival, validate the prognostic significance of PA, and monitor nutritional and therapeutic interventions in this patient population.