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Number of results: 14
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Abstract

In the theory of open systems one mentions equifinality – by drawing from various sources, one may reach the same results. The new linguistic phenomenon, which emerged due to equifinality, upsets the stability of the system, causes various types of re‑evaluation, therefore the same source causes different results. Thus, one may speak about equipotentiality. In her article, the author demonstrates how the adverbia which emerged in the late part of the Proto‑Slavic period influenced the word‑formative system of the Polish language. She focuses on the adverbs with the formants ‑o and ‑e, a class which was thriving already in the earliest period of the written Polish language (more than 500 units in the Old Polish period).
In adjectives, the adverb influenced the gradual decline of intensifying prefixes prze‑ ( przedobry ‘extremely good’) and nad‑ ( nadpełny ‘Latin: superplenus’), and on the basis of the elative na(j)‑ and ‑ szy there emerged the morphosyntactic category of grade. The development of the category of disintensification took a different direction.
Adverbs were one of the reasons which caused the decline of diminutive and augmentative verbs. The traces of these categories are preserved in the following words used in the modern Polish language: głaskać ‘to fondle, to caress, to stroke gently’, nadskakiwać ‘to fawn, to flatter, to toady’. Adverbs also influenced the gradual decline of obsolete iterativa, their properties were assumed by adverbs ( palać – często palić ‘to smoke often’).
Many original adverbs shifted to the class of functional expressions, assuming a metatextual role – of commenting upon one’s own, current utterances. Sometimes they perform the functions of thematic operators ( Intelektualnie Marek ma cechy lidera, emocjonalnie absolutnie nie ‘Mark has the qualities of a leader intellect‑wise, but not at all emotion‑wise); rhematic operators (particles, e.g. Janek podobno wyjechał ‘Janek supposedly went away’), appositions: A pani czytała to?Naturalnie! ‘And have you read it? – Naturally!’
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Authors and Affiliations

Krystyna Kleszczowa
1
ORCID: ORCID

  1. Uniwersytet Śląski Katowice
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Abstract

Currently is the biggest problem of metallurgical companies the increase of fossil fuel prices and strict environmental regulations. As a result of this, companies must look for alternatives that would reduce the amount of fossil fuels and reduce emissions. Wood sawdust has huge energy potential, which can be used in the process of agglomerate production. This type of energy is locally available, has some similar properties as fossil fuels and is economically advantageous. For these reasons, experimental study using laboratory agglomeration pan was realized to study the possibility of agglomerate production with a mixed fuel. Experimental results show the viability of mixed fuel use in the agglomeration process, but also show significant possibility for improvement. The maximum acceptable substitution ratio, which corresponds to qualitatively suitable agglomerate is 20% of pine sawdust. Based on the realized experiments and the obtained results we have acceded to the intensification of the agglomeration process with an objective to increase the amount of added substitution fuel while maintaining the required quality of agglomerate.

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Authors and Affiliations

Z. Semanová
J. Legemza
M. Hrubovčáková
R. Findorák
M. Fröhlichová
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Abstract

The shell and coil heat exchangers are commonly used in heating, ventilation, nuclear industry, process plant, heat recovery and air conditioning systems. This type of recuperators benefits from simple construction, the low value of pressure drops and high heat transfer. In helical coil, centrifugal force is acting on the moving fluid due to the curvature of the tube results in the development. It has been long recognized that the heat transfer in the helical tube is much better than in the straight ones because of the occurrence of secondary flow in planes normal to the main flow nside the helical structure. Helical tubes show good performance in heat transfer enhancement, while the uniform curvature of spiral structure is inconvenient in pipe installation in heat exchangers. Authors have presented their own construction of shell and tube heat exchanger with intensified heat transfer. The purpose of this article is to assess the influence of the surface modification over the performance coefficient and effectiveness. The experiments have been performed for the steady-state heat transfer. Experimental data points were gathered for both laminar and turbulent flow, both for co current- and countercurrent flow arrangement. To find optimal heat transfer intensification on the shell-side authors applied the number of transfer units analysis.

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Authors and Affiliations

Rafał Andrzejczyk
Tomasz Muszyński
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Abstract

Preparation and properties of hierarchically structured porous silica monoliths have been discussed from the viewpoint of their application as continuous microreactors for liquid-phase synthesis of fine chemical in multi kilogram scales. The results of recent topical papers published by two research teams of Institute of Chemical Engineering Polish Academy of Sciences (ICE) and Department of Chemical Engineering and Process Design, Chemical Faculty, Silesian University of Technology (SUT) have been analyzed to specify the governing traits of microreactors. It was concluded that even enhancement factor of 100 in activity, seen in enzyme catalyzed reactions, can be explained by a proportional reduction of its physical constraints, i.e. huge enhancement of external mass transfer and micromixing. It is induced by very chaotic flows of liquid in tens of thousands of waving connected channels of ca. 25–50 mm in diameter, present in the skeleton. The scale of enhancement in the case of less active catalysts was smaller, but still large enough to consider the most practical applications.

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Authors and Affiliations

Julita Mrowiec-Białoń
Agnieszka Ciemięga
Katarzyna Maresz
Katarzyna Szymańska
Wojciech Pudło
Andrzej B. Jarzębski
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Abstract

A novel absorbing pervaporation hybrid technique has been evaluated experimentally for the recovery of ammonia from the gas mixture in a recycle loop of synthesis plants. This process of hybridization brings together the combination of energy-efficient membrane gas separation based on poly(dimethylsiloxane) poly(diphenylsilsesquioxane) with a high selective sorption technique where a water solution with polyethylene glycol 400 (PEG-400) was used as the liquid absorbent. Process efficiency was studied using the pure and mixed gases. The influence of PEG-400 content in aqueous solutions on process selectivity and separation efficiency was studied. The ammonia recovery efficiency evaluation of an absorbing pervaporation technique was performed and compared with the conventional membrane gas separation. It was shown that the absorbing pervaporation technique outperforms the conventional membrane method in the whole range of productivity, producing the ammonia with a purity of 99.93 vol.% using the PEG 80 wt.% solution. The proposed method may be considered as an attractive solution in the optimization of the Haber process.

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Authors and Affiliations

Artem A. Atlaskin
Anton N. Petukhov
Nail R. Yanbikov
Maria E. Salnikova
Maria S. Sergeeva
Vladimir M. Vorotyntsev
Ilya V. Vorotyntsev
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Abstract

The main aim of this work is to study the thermal efficiency of a new type of a static mixer and to analyse the flow and temperature patterns and heat transfer efficiency. The measurements were carried out for the static mixer equipped with a new mixing insert. The heat transfer enhancement was determined by measuring the temperature profiles on each side of the heating pipe as well as the temperature field inside the static mixer. All experiments were carried out with varying operating parameters for four liquids: water, glycerol, transformer oil and an aqueous solution of molasses. Numerical CFD simulations were carried out using the two-equation turbulence k-ω model, provided by ANSYS Workbench 14.5 software. The proposed CFD model was validated by comparing the predicted numerical results against experimental thermal database obtained from the investigations. Local and global convective heat transfer coefficients and Nusselt numbers were detrmined. The relationship between heat transfer process and hydrodynamics in the static mixer was also presented. Moreover, a comparison of the thermal performance between the tested static mixer and a conventional empty tube was carried out. The relative enhancement of heat transfer was characterised by the rate of relative heat transfer intensification.

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Authors and Affiliations

Maciej Konopacki
Marian Kordas
Karol Fijałkowski
Rafał Rakoczy
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Abstract

The paper presents the experimental study of a novel unsteady-statemembrane gas separation approach for recovery of a slow-permeant component in the membrane module with periodical retentate withdrawals. The case study consisted in the separation of binary test mixtures based on the fast-permeant main component (N2O, C2H2) and the slow-permeant impurity (1%vol. of N2) using a radial countercurrent membrane module. The novel semi-batch withdrawal technique was shown to intensify the separation process and provide up to 40% increase in separation efficiency compared to a steady-state operation of the same productivity.

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Authors and Affiliations

Stanislav V. Battalov
Maxim M. Trubyanov
Egor S. Puzanov
Tatyana S. Sazanova
Pavel N. Drozdov
Ilya V. Vorotyntsev
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Abstract

Humic acids (HAs) are components of natural organic matter found in soil and are considered responsible for its fertility. They can be extracted from sources such as peat and lignite on an industrial scale. In order to increase the efficiency and reduce the duration of the alkaline extraction step, microwave-assisted extraction (MAE) was used in this study. Statistical analysis was implemented to describe the influence of microwave power, temperature, and time on the yield of HA extraction. Experimental points were created on the basis of the matrix, according to the Box-Behnken design. Statistical analysis showed the importance of linear correlations between the process parameters and the response. The last part of the presented study was to create the polynomial model and response surface plots, attached in poster form, which describe the result as a function of parameters of the MAE process.
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Authors and Affiliations

Kinga M. Marecka
1
ORCID: ORCID
Dominik Nieweś
1
ORCID: ORCID
Magdalena Braun-Giwerska
1
ORCID: ORCID
Marta Huculak-Mączka
1
ORCID: ORCID

  1. Wrocław University of Science and Technology, Department of Chemical Process Engineering and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland
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Abstract

Vapordynamic thermosyphon (VDT) is an efficient heat transfer device. The two-phase flow generation and dynamic interaction between the liquid slugs and vapor bubbles in the annular minichannel of the VDT condenser are the main features of such thermosyphon, which allowed to increase its thermodynamic efficiency. VDT can transfer heat in horizontal position over a long distance. The condenser is nearly isothermal with the length of tens of meters. The VDT evaporators may have different forms. Some practical applications of VDT are considered.
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Authors and Affiliations

Leonard Vasiliev
Leonid Vasiliev
Alexander Zhuravlyov
Aleksander Shapovalov
Aleksei Rodin
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Abstract

Two-dimensional numerical investigations of the fluid flow and heat transfer have been carried out for the laminar flow of the louvered fin-plate heat exchanger, designed to work as an air-source heat pump evaporator. The transferred heat and the pressure drop predicted by simulation have been compared with the corresponding experimental data taken from the literature. Two dimensional analyses of the louvered fins with varying geometry have been conducted. Simulations have been performed for different geometries with varying louver pitch, louver angle and different louver blade number. Constant inlet air temperature and varying velocity ranging from 2 to 8 m/s was assumed in the numerical experiments. The air-side performance is evaluated by calculating the temperature and the pressure drop ratio. Efficiency curves are obtained that can be used to select optimum louver geometry for the selected inlet parameters. A total of 363 different cases of various fin geometry for 7 different air velocities were investigated. The maximum heat transfer improvement interpreted in terms of the maximum efficiency has been obtained for the louver angle of 16° and the louver pitch of 1.35 mm. The presented results indicate that varying louver geometry might be a convenient way of enhancing performance of heat exchangers.

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Authors and Affiliations

Tomasz Muszyński
Sławomir Marcin Kozieł
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Abstract

In this paper we studied the intensification of the water clarification process on contact clarifiers with quartz sand fil-tering bed, which was modified with a solution of aluminum sulphate coagulant. The modification of the quartz sand filter-ing bed was carried out by applying to the surface of grains of quartz sand solution of coagulant aluminum sulphate with different doses. Investigation of the electrokinetic potential of the filtering material (quartz sand) was carried out by the percolation potential method.

The influence of electrical properties (size and sign of the charge) of the filtering bed itself and suspended solids in the water on the filtration process was studied. The filter material – quartz sand used in contact clarifiers has a negative electric charge. When the electric charge of the particles decreases, that is, as the ζ-potential decreases, the repulsive forces de-crease and it the adhesion of particles becomes possible. This is the process of coagulation of the colloid. The forces of mu-tual gravity between the colloidal particles begin to predominate over the electric repulsive forces at the ζ-potential of thesystem less than 0.03 V.

Modification of quarts filtering bed with a solution of coagulant aluminum sulphate recommended for the purification of surface water allows: to intensify the process of water clarification, to reduce the consumption of reagents by 25–30%, with the obtaining purified water of the required quality, to reduce the production areas necessary for reagent management of treatment facilities, and to reduce the cost of water treatment by 20–25%.

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Authors and Affiliations

Stanislav S. Dushkin
Serhii Martynov
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Abstract

A proper selection of steam reforming catalyst geometry has a direct effect on the efficiency and economy of hydrogen production from natural gas and is a very important technological and engineering issue in terms of process optimisation. This paper determines the influence of widely used seven-hole grain diameter (ranging from 11 to 21 mm), h/d (height/diameter) ratio of catalyst grain and Sh/St (hole surface/total cylinder surface in cross-section) ratio (ranging from 0.13 to 0.37) on the gas load of catalyst bed, gas flow resistance, maximum wall temperature and the risk of catalyst coking. Calculations were based on the one-dimensional pseudo-homogeneous model of a steam reforming tubular reactor, with catalyst parameters derived from our investigations. The process analysis shows that it is advantageous, along the whole reformer tube length, to apply catalyst forms of h/d = 1 ratio, relatively large dimensions, possibly high bed porosity and Sh/St ≈ 0.30-0.37 ratio. It enables a considerable process intensification and the processing of more natural gas at the same flow resistance, despite lower bed activity, without catalyst coking risk. Alternatively, plant pressure drop can be reduced maintaining the same gas load, which translates directly into diminishing the operating costs as a result of lowering power consumption for gas compression.

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Authors and Affiliations

Ewelina Franczyk
Andrzej Gołębiowski
Tadeusz Borowiecki
Paweł Kowalik
Waldemar Wróbel
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Abstract

Technological assurance and improvement of the economic efficiency of production are the

first-priority issues for the modern manufacturing engineering area. It is possible to achieve

a higher value of economic efficiency in multiproduct manufacturing by multicriteria optimization.

A set of optimality criteria based on technological and economic indicators was

defined with the aim of selecting the optimal manufacturing process. Competitive variants

and a system of optimization were developed and investigated. A comparative analysis of

the optimality criteria and their influence on the choice of optimal machining processes was

carried out. It was determine

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Authors and Affiliations

Alexey Kotliar
Yevheniia Basova
Vitalii Ivanov
Olena Murzabulatova
Svitlana Vasyltsova
Mariia Litvynenko
Olena Zinchenko

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