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Number of results: 8
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Abstract

The author of the text focuses on the economics of everyday life as defined by a contextual and qualitative measuring of various aspects of hospitality through the use of terms such as “more,” “less,” and “just right.” He analyzes the presence of food, alcohol, and coffee during the visit of guests. Each of these three material components of hospitality is regulated according to specific principles: “too much is better than too little” in regard to food, “too little is better than too much” for alcohol, and there has to be “at least” coffee. A detailed analysis of these principles leads to the conclusion that Polish hospitality is today oriented toward moderation. The popular belief in the abundance of Polish hospitality as a national feature is thus called into question.
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Authors and Affiliations

Ariel Modrzyk
1
ORCID: ORCID

  1. Uniwersytet im. Adama Mickiewicza
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Abstract

Alcohol is a recognized teratogen that affects various aspects of fetal development. Tissue that is particularly susceptible to its teratogenicity is neuronal tissue. The effect of prenatal alcohol exposure (PAE) on the central nervous system has been extensively studied, yet the knowledge on the influence of PAE on the autonomic nervous system is scarce. The purpose of this article is to review the current state of knowledge about the impact of PAE on the autonomic nervous system. Studies conducted on the PAE animal model have shown that prenatal alcohol exposure is associated with significant alterations in the autonomic nervous system, but the mechanisms and consequences are not yet clearly defined. It was established that PAE causes decreased heart rate variability (HRV) in fetal cardiotocography. Several studies have revealed that later, in infancy and childhood, reduced parasympathetic activity with or without compensating sympathetic activity is observed. This may result in behavioral and attention disorders, as well as an increased predisposition to sudden infant death syndrome. Both animal and human studies indicate that the relationship between PAE and autonomic dysfunction exists, however large, well-designed, prospective studies are needed to confirm the causal relationship and characterize the nature of the observed changes.

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Authors and Affiliations

Michał Jurczyk
Katarzyna Anna Dyląg
Kamil Skowron
Krzysztof Gil
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Abstract

Kinetic studies of esterification reaction of maleic anhydride with butan-1-ol, 2-methylpropan-1-ol and butan-2-ol were carried out in a semibatch reactor, in the presence of four acidic catalysts: sulfuric acid, phosphotungstic acid, ion exchange resin Dowex 50WX8 and tetrabutyl zirconate. Phosphotungstic acid proved to be the most active catalyst. The temperature range was 383–413 K, the initial molar ratio of alcohol to acid ranged 2.2-5:1. The kinetic parameters were given. The kinetics appeared to be that of the second order with respect both to the acid and to the alcohol. The reaction carried out in the presence of tetrabutyl zirconate was very slow and depended only on acid concentration. The effect of temperature on the reaction rate follows the Arrhenius equation well.
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Authors and Affiliations

Maria Bartoszewicz
1
Maria Kulawska
2
Wiesław Organek
2

  1. Łukasiewicz Research Network – Institute of Heavy Organic Synthesis “Blachownia”, Energetyków 9, 47-225 Kędzierzyn-Koźle, Poland
  2. Polish Academy of Sciences, Institute of Chemical Engineering, Bałtycka 5, 44-100 Gliwice, Poland
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Abstract

Polish Academy of Sciences, Institute of Chemical Engineering, 44-100 Gliwice, Bałtycka 5, Poland A review concerning main processes of hydrogenation of carbon oxides towards synthesis of methanol, mixture of methanol and higher aliphatic alcohols and one-step synthesis of dimethyl ether as well as methanol steam reforming is given. Low-temperature methanol catalysts and lowtemperature modified methanol catalysts containing copper as primary component and zinc as secondary one are described.

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Authors and Affiliations

Maria Kulawska
Maria Madej-Lachowska
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Abstract

The subject of this paper was to compare the influence of selected coatings on bending strength of moulds and cores manufactured in a furan technology. In a range of study, there were used three kinds of coatings - water based coating and two kind of alcohol based coating manufactured by FOSECO. Coating were applicated by brush, overpouring/flow and spraying. For each application method, there were realized different kind of drying- at ambient temperature, in a furnace and by burning. Physicochemical properties of coatings were such selected to accommodate them to the application method and type of coating. Based on the conducted studies it was observed that for water based coating application method doesn’t have an important influence on bending strength and it is necessary to optimize the time and temperature of drying to achieve better results of bending strength. For alcohol based coatings, drying by burning causes significant deterioration of bending strength of the mould and core and drying process at ambient allows to obtain high bending strength of mould/cores in regard to time of drying.
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Authors and Affiliations

J. Dorula
R. Romelczyk
N. Przyszlak
B. Siodmok
A. Studnicki
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Abstract

The purpose of this paper was to search the relations between the structure of the compressed expanded graphite – polymer – turbostratic carbon composites on successive stages of technological treatment and parameters describing the acoustic emission phenomena in these materials. The acoustic emission method can be used for measurements of changes in the structure and many different properties of materials. These investigations are a continuation of our earlier studies concerning physical, mechanical and chemical properties of porous composites created on the basis of a compressed expanded graphite matrix, obtained after successive technological procedures of impregnation, polymerization and carbonization of polyfurfuryl alcohol. The aim of this work was to investigate materials obtained at different levels of technological processing, thus with different densities, porosity, physical and chemical properties, by using the acoustic emission method. In compressed expanded graphite composites structures one can differentiate two basic directions: perpendicular to the bedding plane of graphite flakes and parallel to this one. The all presented results were obtained for the uniaxial strain applied in the direction perpendicular to the bedding plane of the composite structure. Analysis of acoustic emission parameters provides information on physical and chemical processes in these materials.

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Authors and Affiliations

A. Berdowska
J. Berdowski
F. Aubry
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Abstract

In the present study, a novel PVA–g–PMA hybrid membrane was developed for application in direct methanol fuel cell (DMFC). Maleic anhydride (MA) was grafted on polyvinyl alcohol (PVA) both ionically and chemically using potassium persulfate (KPS), for the first time. ThePVA–g–PMA thus synthesized was then blended with 3–Amino–4–[3–(triethylammonium sulfonato)phenyl amino]phenylene hydrochloride. The prepared membranes were characterized by FT–IR, TGA. 0.0104 S/cm of proton conductivity was found for the membrane. The ion exchange capacity was found to be 2.175 meq/g and the water uptake capacity as 14.9%. The single-chamber fuel cell power density was higher (34.72 mW/cm2) and current density (62.11 mA/cm2) when compared to Nafion 117 membrane.
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Authors and Affiliations

Pratima Gajbhiye
1
A.K. Tiwari
2
Karan Mann
1
J.S. Kahlon
1
H. Upadhyay
3

  1. School of Chemical Engineering and Physical Sciences, Lovely Professional University, Phagwara, Punjab-144 411, India
  2. Department of Chemical Engineering, NIT Jalandhar, Punjab-144011, India
  3. School of Agriculture, Lovely Professional University, Phagwara, Punjab-144 411, India
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Abstract

The main aim of the study was to search for the relationship between the anisotropy of the structure of polyfurfuryl alcohol (PFA) – polymer/compressed expanded graphite (CEG)-matrix composites at subsequent stages of the technological process and characteristics of the acoustic emission (AE) descriptors. These composites, obtained after successive technological procedures of impregnation, polymerization, and carbonization, possess different structure, densities, porosity, and other physicochemical properties. In the structures of composites prepared on the basis of CEG, two basic directions can be distinguished: parallel to the bedding plane of graphite sheets and perpendicular to it. The measurements were carried out for the stress acting in these two main directions. The investigation has shown that the AE method enables the detection of anisotropy in the structure of materials. The results of the research show that all four of the acoustic emission descriptors studied in this work are sensitive to the technological stages of these materials on the one hand and their structure anisotropy on the other. Fourier analysis of the recorded spectra provides interesting conclusions about the structural properties of composites as well as a lot of information about the bonding forces between the carbon atoms of which the CEG matrix is composed and the PFA polymer or turbostratic carbon.
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Authors and Affiliations

Sylwia Berdowska
1
Janusz Berdowski
1 2
Aubry Frederic
3

  1. Faculty of Electrical Engineering, Czestochowa University of Technology, Al. Armii Krajowej 17, 42-200 Częstochowa, Poland
  2. Faculty of Science and Technology, J. Dlugosz University in Czestochowa, Al. Armii Krajowej 13/15, 42-200 Częstochowa, Poland
  3. Maitrise de Chimie-Physique, Université Henri Poincaré, Nancy, France

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