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Wanda Wilczyńska-Michalik and Marek Michalik

Celestite in the Weathering Crust on Limestone Exposed to an Urban Atmosphere in Cracow (Poland)

Celestite containing very low amounts of barium occurs in weathering reaction zones developed on the Pińczów limestone exposed to the polluted atmosphere of Cracow. The mineral occurs both in limestone pore spaces filled with gypsum and in black gypsum crust. The Pińczów limestone contains ca 500 ppm strontium which was released during the reaction with atmospheric pollutants. The nucleation and growth of celestite, requiring significant concentration of components in evaporating solutions, is associated with gypsum crystallization.

Open access

Arkadiusz Derkowski and Marek Michalik

Statistical Approach to the Transformation of Fly Ash into Zeolites

The experimental conversion of F-class fly ash into zeolites is described. The ash, composed mainly of aluminosilicate glass, mullite and quartz, was collected in the Cracow power plant (southern Poland). The experiments involved the heating of fly ash samples in PTFE vessels. Time, temperature and solution composition were the reaction parameters considered in the experiments and in the subsequent modeling. A series of reactions with 0.5, 3 and 5M NaOH solutions (and some with additional 3M NaCl) were carried out at 70°, 100° and 150°C for 12-48 hours under autogenic pressure (not measured) and at a constant ash-to-solution ratio of 33.3 g/l. The following zeolite phases were synthesized: sodalite (SOD structure), hydroxysodalite (SOD), CAN type phases, Na-X (FAU), and NaP1 (GIS). Statistically calculated relationships based on the mineral- and chemical compositions of the reaction products support the conclusion that the type of zeolite phase that crystallizes depends on the concentration of OH- and Cl- in solution and on the temperature of the reaction. The duration of reaction, if on the order of tens of hours, is of less significance. The nature of the zeolite phase that crystalises is controlled by the intensity and selectivity of the substrate dissolution. That dissolution can favour, in sequence, one or other of the components in the substrate, resulting in Si/Al variation in the reaction solutions. Mullite dissolution (decreasing solution Si/Al) characterizes the most advanced reaction stages. The sequence of crystallization of the zeolite phases mirrors the sequential dissolution of substrate components, and the composition of the crystallizing zeolite crystals reflects the changes in the solution Si/Al.

Open access

Maja Stanisławska and Marek Michalik

Xenotime-(Y) veins in a Neoproterozoic metamudstone (Małopolska Block, S Poland)

First occurrence of xenotime-(Y) veins in the Neoproterozoic metamudstone, NW margin of the Małopolska Block, is reported here. The veins are <5 μm thick, inhomogeneous and of varied morphology. Their textural characteristics, exhibiting very low U and Th contents (<1 wt%) and relatively high heavy rare earth elements (REE) contents (12-24 REE2O3 wt%), suggest hydrothermal genesis, though diagenetic precursors of the veins are not excluded. The veins provide good evidence of the mobility of Y, REE, U and Th in low-temperature conditions (anchimetamorphic to greenschist facies). The observed differences in the chemical composition of the veins may indicate multiple stages of formation, possibly during several hydrothermal events that affected the area.

Open access

Marek Michalik, Andrzej Skowroński and Monika Kasina

Editorial

Open access

Ryszard Kryza, Marek Michalik and Piotr Wyszomirski

2009: 40th Birthday of the Mineralogical Society of Poland

Open access

Wanda Wilczyńska-Michalik, Kamil Rzeźnikiewicz, Bartłomiej Pietras and Marek Michalik

Abstract

During single particle analysis of aerosol in Kraków (Poland) we noticed a new component, that is, aggregates of TiO2 particles. These aggregates are from 0.5 to 4 μm and are composed of individual particles whose size typically varies from between 100 and 350 nm. Smaller particles (below 100 nm) also occur. TiO2 particles are relatively abundant in the summer. The size distribution of the particles corresponds to “pigmentary” TiO2, which indicates that they could be derived from paints and building materials. TiO2 particles were not previously identified in aerosol samples in Kraków, and therefore this phenomenon is likely to be related to the common usage of new building materials and paints. A review of the literature suggests that TiO2 particles, especially within the nanosize range, could result in health and environmental impacts; however, evaluation of the actual threat is difficult.

Open access

Kamil Michalik, Marek Zatoń, Paulina Hebisz and Rafał Hebisz

Abstract

Introduction. Since mountain biking involves exercise of varying intensity, competitive performance may be affected by the rate of recovery. The aim of the current study was to determine whether maximal oxygen uptake is associated with the rate of heart rate and oxygen uptake recovery in mountain bike athletes.

Material and methods. The study examined 29 mountain bikers, including members of the Polish National Team. These athletes specialised in cross-country Olympic (XCO) racing. After undergoing a graded stress test on a cycle ergometer, the subjects were divided into two groups: G1, consisting of athletes with higher aerobic capacity (n = 12; VO2max > 60 ml∙kg−1∙min−1), and G2, comprising athletes with lower aerobic capacity (n = 17; VO2max < 55 mL∙kg−1∙min−1). Heart rate and oxygen uptake recovery was measured after the graded stress test in a sitting position.

Results. HRmax values did not differ significantly between the two groups. HR1’, HR2’, and HR4’ values recorded for G1 were statistically significantly lower compared to those achieved by G2. %HR1’, %HR2’, %HR4’, and %HR5’ values were also significantly lower in G1 than in G2. No significant differences were found in oxygen uptake during recovery (VO2-1’, 2’, 3’, 4’, 5’) between the two groups. Significantly lower %VO2max-1’, %VO2max-2’, and %VO2max-5’ values were observed in G1 compared to those in G2. No significant correlations were found between VO2max per kilogram of body mass and the recovery efficiency index in either group. There was, however, a statistically significant correlation between VO2max and the recovery efficiency index (R = 0.52) in the entire group of athletes (n = 29).

Conclusion. The study showed that the work capacity of mountain bike athletes was associated with the rate of heart rate and oxygen uptake recovery.

Open access

Marek Zatoń and Kamil Michalik

Abstract

Purpose. The aim of this study was to investigate the influence of 8-week-long interval training (targeting glycolytic capacity) on selected markers of physical fitness in amateur long-distance runners. Methods. The study involved 17 amateur long-distance runners randomly divided into an experimental (n = 8) and control (n = 9) group. The control group performed three or four continuous training sessions per week whereas the experimental group performed two interval running training sessions and one continuous running training session. A graded treadmill exercise test and the 12-min Cooper test were performed pre- and post-training. Results. O2max and the rate of recovery increased in the experimental group. Relative oxygen uptake, minute ventilation, and heart rate speed decreased in low- (6 km/h) and medium-intensity (12 km/h) running. Conclusions. Both training modalities showed similar results. However, the significant differences in training volume (4-8 min interval training vs. 40-150 min continuous training) indicates that the modalities targeting glycolytic capacity may be more efficient for amateur runners prepare for long-distance events.

Open access

Łukasz Rutkowski, Marek Zatoń and Kamil Michalik

Abstract

Purpose. The aim was to investigate the relationship between aerobic fitness as ascribed by maximum oxygen uptake (VO2max) and post-exercise recovery after incremental exercise to volitional exhaustion.

Methods. A sample of 17 professional cyclists (age 17.4 ± 3.1 years; VO2max 61.1 ± 7.2 ml/min/kg) were recruited. A graded exercise test was administered on a cycle ergometer. Upon termination, the participants remained seated, and oxygen uptake (VO2), minute ventilation (VE), and heart rate (HR) were measured in the 1st, 3rd, and 5th minute of recovery.

Results. Post-exercise VO2 dynamics revealed a 69% and 80.9% reduction from VO2max in the 1st and 5th minute, respectively. HR decreased only by 41% of HRmax, in the 5th minute of recovery. A positive correlation between the differential rate of recovery for VO2 and VO2max indicated a dependency between aerobic fitness and recovery potential. Correlative strength decreased with time, and by the 5th minute of recovery a significant correlation was evidenced only between VO2 and VE.

Conclusions. As recovery potential is associated with the aerobic fitness level, training effects may be monitored based on the recovery of VO2 and HR to pre-exercise values.

Open access

Monika Kasina and Marek Michalik

Abstract

The recovery of valuable metals from metallurgical slag disposals is a promising option to protect natural resources, limited due to technology development and increased consumption. The Ad-hoc Working Group on Defining Critical Raw Materials within the Raw Materials Supply Group has proposed a list of critical elements which have the greatest economic importance and meet the requirements of sustainable development in Europe. The goal of this study was to examine steelmaking- and blast-furnace slags from metallurgical processes to determine concentrations of elements of the greatest criticality for Poland, e.g. Nb, Ta and REE, and to discuss the viability of their recovery. Slag analyses indicate enrichment of REE relative to UCC, NASC and average chondrite compositions in blast-furnace slags and Nb and Ta in steelmaking slags. To make recovery of these critical elements reasonable and profitable, it is recommended that they be recovered together with other useful raw materials.