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Open access

Elwira Tomczak and Paweł Tosik

Abstract

Azo dye-plant sorbent system was investigated in the paper. Direct Orange 26 and Reactive Blue 81 azo dyes were sourced from Boruta-Zachem Kolor Sp. z o.o. Mechanically and chemically modified rye straw was used as a “low-cost” biosorbent. During experiments, dye concentration changes in the solution and sorbent in time were measured at constant temperature until equilibrium was reached. Sorption equilibrium was described by 2-parameter (Freundlich, Langmuir) and 3-parameter (Redlich-Peterson and Radke-Prausnitz) equations widely used in adsorption studies. Characteristic coefficients of equations were determined and the proposed approximations of the results of experimental studies were evaluated statistically. Higher sorption capacity was obtained for Direct Orange 26 than for Reactive Blue 81.

Open access

Elwira Tomczak and Paweł Tosik

Abstract

This paper discusses the adsorption of Direct Orange 26 azo dye on sunflower husk - an agricultural waste product. During the study, sorption kinetics and equilibrium as well as sorption capacity of the husk were investigated. The adsorption kinetics was analyzed using pseudo-first and pseudo-second order equations, which indicated a chemical sorption mechanism. The sorption equilibrium was approximated with the two-parameter Freundlich and Langmuir equations and the three-parameter Redlich-Peterson equation. The main experiments were carried out in a laboratory adsorption column under different process conditions. Experimental data were interpreted with the Thomas model, based on the volumetric flow rate, initial composition of the feed solution and mass of the adsorbent. The results of modeling the adsorption equilibrium, adsorption kinetics and adsorption dynamics were evaluated statistically.

Open access

Arkadiusz Tomczak, Paweł Zalewski and Rafał Gralak

Abstract

Modern Integrated Navigation Systems (INS) integrate information obtained from various sensors and functions. Processed data are presented on the computer display generally with the aim to increase navigator’s situation awareness and to reduce his/her workload. The investigations described in the paper were carried out to assess the advantages of the new functionality of the test INS (e-Navigation enhanced Integrated Navigation System ee-INS), developed in the EU financed EfficienSea Project, that looks and works like a standard ECDIS. This new functionality implements ‘Exchange of Intended Route’ service. The experiment was conducted in a full mission ship simulator environment with 20 experienced mariners. The bridge layout without ECDIS ‘Exchange of Intended Route’ functionality, and bridge layout with this functionality implemented, was applied in research and its results enabled to carry out their comparison. The navigators’ workload was measured by NASA-TLX method. Navigators’ situation awareness in respect to other ship’s state and the final passing distance were utilized to evaluate safety of navigation process.

Open access

Andrzej Tomczak, Paweł Różański and Ewa Jówko

Abstract

Introduction. Taking up emergency actions when fighting various types of natural disasters requires appropriate psychophysical preparation. Thanks to the development of technique, coordination motor abilities have gained greater importance than physical strength and endurance in such activities. The purpose of the present work was to assess the impact of 36 hours of survival activities and sleep deprivation on selected coordination motor abilities in students of the University of Physical Education. Material and methods. The study involved 12 male students of the University of Physical Education in Warsaw, specialising in “Physical Education in Uniformed Services”. The age of the participants was 21.0 ± 0.74 years, their body height was 179.5 ± 5.6 cm, and their body mass was 74.6 ± 8.0 kg. The assessment was performed based on the following coordination motor ability tests: a test measuring the differentiation of the use of forearm muscle strength, a running motor adjustment test, and a measurement of divided attention. A test involving shooting from a pneumatic gun and a measurement of the maximal force of the forearm were also carried out. Tests and trials were conducted before training (P1), after 24 hours of training (P2), after completing the training - that is after 36 hours of training (P3), and after 12 hours of rest (P4). During the training, the participants completed 12 km on foot, paddled for approximately 6 hours, rowed kayaks for about 4 hours, and performed survival tasks. Results. The analysis of the results of the study of maximal force and the ability to differentiate forearm muscle strength showed that the forearm muscle strength remained at the same level during the entire training. The ability to differentiate forearm muscle strength deteriorated after night training. There were no statistically significant differences in the results of the running motor adjustment tests and in shooting performance between individual measurements. Conclusions. Participation in long-term survival training with very low intensity, combined with sleep deprivation, caused a temporary deterioration in the ability to differentiate forearm muscle strength. This may indicate that people involved in rescue operations during which the psychophysical load is small will be able to perform tasks correctly for a long time.

Open access

Pawel Tomczak and Jakub Traczyk

Abstract

The anchoring heuristic refers to phenomena when an arbitrary number affects subsequent numerical estimations. Oppenheimer, LeBoeuf and Brewer (2008) showed that it is not necessary for the anchor to be a numerical value (i.e., the act of drawing lines of different length effectively shifts numerical estimations), yet current models describing the anchoring heuristic do not fully account for the mechanism of non-numerical anchoring. However, this effect shows similarity to the basic anchoring effect - obtained without the comparative question and based on the availability of the given number in working memory. In this study, we attempt to verify whether those two effect share the same psychological mechanism. In Experiment 1, we show that non-numerical anchoring based on magnitude priming cannot be obtained when the lines are just observed. The examined mechanism proves to be dependent on the act of drawing, displaying limitations similar to the basic anchoring effect, previously pointed out by Brewer and Chapman (2002). By using the same numerical anchors in different size formats, in Experiment 2 we showed that anchoring based on magnitude priming occurs even when the numerical values do not affect the estimations. The results are discussed in the light of a possible mechanism that underlies the investigated effect.