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Volume 6, Year 2015, Issue 3, July-September

Investigation on lineworks printed with different types of flexographic printing forms for purposes of printed electronics
Author:
Juliusz Krzyżkowski, Tomasz Dąbrowa, Jacek Hamerliński, Przemysław Śleboda
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21 x
 

Abstract: Nowadays one can observe fast development of materials and technologies dedicated to inexpensive mass production of electronic devices with conventional printing techniques. One of them is flexography. In this paper investigation on quality of lineworks printed with flexographic printing technique for purposes of printed electronics is presented. There was analysed influence of different printing forms on printed elements reproduction accuracy. Results obtained with conventional graphic ink with commercially available conductive ink were compared as well. Aspects which should be taken under consideration when implementing flexography to printed electronics applications have been specified.

Keywords: printed electronics, flexography, printing

Area: Electronics, Telecommunications and Informatics

Color gamut volumes of ink-jet prints made on papers suitable for offset technique
Author:
Katarzyna Piłczyńska, Konrad Blachowski
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10 x
 

Abstract: Ink-jet as a digital technology can be used for carrying out very short runlenghts. This constitutes a very important issue nowadays since the digital printing market was estimated to grow by 71% from 2008 to 2013 year. [1] [2] There are many kinds of papers suitable for ink-jet, yet they are rather expensive. This is the reason why users of digital machines search for cheaper equivalents, i.e. offset papers. Unfortunately, such papers can give bad printing quality. Before using them, a considerable number tests should be carried out in order to check what types of offset paper are useful in ink-jet technique.

Keywords: papers suitable for ink-jet, papers applied in offset printing technique, machine with pigment aqueous-based inks, machine with UV-curable inks, gamut volume, colorimetric spaces, color appearance model

Area: Nanotechnologies and Materials

Separation of nanoparticles and nanodroplets from air using fibrous filters
Author:
Łukasz Werner, Anna Jackiewicz
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16 x
 

Abstract: Separation of particles from gas stream is of great importance in many areas of human life. Air filtering materials have wide applications. They are used inter alia in ventilation and air conditioning systems, in cars to reduce emission from diesel engines, in the device of everyday use (e.g. vacuum cleaner), as a personal protective equipment for example to avoid inhalation hazardous dust from industrial processes. Small airborne particles can cause a variety problems for human health. Long exposure to particles of submicron- and nano-sized has been related to higher death rates due to lung cancer and cardiopulmonary illness. The main object of this study was to investigate filtration efficiency of oil nanodroplets (DEHS di-ethylhexyl sebacate) and salt nanoparticles (KCl) from air using fibrous polypropylene media made by melt-blown technique. Fibrous filters are relatively inexpensive to fabricate and what is the most important they are high efficient with simultaneous low flow resistance. Three types of non-wovens having various morphology with different average fiber diameter were tested. The tests show that both KCl solid nanoparticles and DEHS nano oil-mist can be efficiently separate from the air using melt-blown fibrous materials. Moreover these filters have been also electrically charged by corona discharge.
The filtration efficiency of charged filters (electrets) was compared with efficiency of uncharged (mechanicals) samples. Results showed significant increase in filtration efficiency for the filters with electric charge compared with uncharged ones.

Keywords: electrets, fibrous filters, filtration, nanodroplets, nanoparticles

Area: Nanotechnologies and Materials

Nickel-cobalt separation by solvent extraction method
Author:
Elzbieta Radzyminska-Lenarcik, Agnieszka Wasilewska
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8 x
 

Abstract: Separation of cobalt(II), and nickel(II) ions from nitrate solutions using liquid-liqiud extraction process was reported. The measurements were run at 25oC and at fixed ionic strength equal to 0.5 (KNO3,HNO3). Initial concentrations of Co(II) and Ni(II) nitric acid in the aqueous phase were constant (0.01 M and 0.15 M, respectively). Both 1-hexylimidazole (1), and 1-hexyl-2-methylimidazole (2), both in dichloromethane were used as extractants. Their concentrations in organic phase were varied from 0.01 to 0.25 M. Cobalt(II) in an aqueous solution forms both tetrahedral and octahedral complexes. Nickel(II) forms only a six-coordinate complexes. These general differences help to provide the basis for the various separation processes currently used for cobalt-nickel separation. The steric effect for extractant 2 facilitates the extraction of tetrahedral Co(II) complexes. Extraction percent (%E) of cobalt(II) and nickel(II) in the systems studied were calculated. The percentage extraction increases for increasing values of pH of aqueous phase and is the highest for pH = 7.2. In the aqueous phase, of which the pH = 7.2, there remain 75%Ni(II) and 40% Co(II) for extractant 1 and the respective values for extractant 2 are 85% Ni(II) and 20% Co(II). The steric effect increases selectivity coefficients Co(II)/Ni(II). The highest selectivity coefficients for both extractants were obtained at a pH of aqueous phase = 6.2; their values were 5 and 8.9 for extractants 1 and 2, respectively.

Keywords: separation ions, solvent extraction, cobalt(II), nickel(II), alkylimidazole

Area: Chemistry and Pharmacy

Effect of Cu (II) Cations on 2-Decarboxy-betanin Stability in Aqueous-Organic Solutions
Author:
Anna Skopińska, Dominika Szot, Karolina Starzak, Sławomir Wybraniec
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20 x
 

Abstract: Several important factors, such us pH, exposure to light, oxygen or temperature affect significantly the betalain stability. In particular, the heavy metal ions exert negative effect on stability of betalain colorants and accelerate pigment decomposition. Trace amounts of metal ions may be present in the food products, as well as in food packaging, leading to undesirable colour changes or even discoloration of betalainic foodstuffs. Decarboxylated betalains, such as 2-decarboxy-betanin, generated, e.g. during betalain thermal treatment, may exhibit greater stability than parent pigments. Moreover, obtained derivatives retain attractive color, making them the promising material for study of pigment stability. An effect of Cu2+ cations as the most degradative metal ions on 2-decarboxy-betanin stability was investigated in ethanolic and methanolic solutions. The increase of the concentration of copper cations has a negative impact on stability of 2-decarboxy-betanin. The cations of Cu (II) in the presence of organic solvents induce the pigment degradation, while the increase of the concentration of organic solvents enhances the pigment decomposition. The main degradation products of the 2-decarboxy-betanin are compounds possessing absorption maxima at λmax ca. 430 nm. These studies allow obtaining the information needed for proper isolation and treatment of pigments, as well as proper storage of products containing betalains.

Keywords: betacyanins, 2-decarboxy-betanin, copper ions, betalain stability, Beta vulgaris L.

Area: Chemistry and Pharmacy

Differences in populations of filamentous bacteria involved in foaming and bulking of activated sludge
Author:
Aleksandra Miłobędzka, Adam Muszyński
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16 x
 

Abstract: Bulking and foaming of activated sludge are related to excessive proliferation of a specific group of activated sludge biocenosis – filamentous bacteria. The research was carried out to compare filamentous bacteria populations in foam and activated sludge in a full-scale municipal wastewater treatment plant located near Warsaw (Poland). Fluorescent in situ hybridization (FISH) – a quantitative, culture-independent, molecular method was applied to evaluate the structure of filamentous populations. Activated sludge and foam were examined for the abundance of eleven groups of these microorganisms, which occur in wastewater treatment plants in Europe. Filamentous bacteria constituted 18% and 24% of all bacteria detected in sludge and foam, respectively. The structures of filamentous bacteria populations in sludge and foam were different, although the same bacteria were found in both types of samples. The most abundant filaments belonged to phylum Chloroflexi (targeted by the CFXmix probe) and genus Microthrix (targeted by the MPAmix probe) in sludge and foam, respectively. The third significantly abundant bacteria was Haliscomenobacter hydrossis (targeted by HHY654).

Keywords: FISH, filamentous bacteria, sludge bulking, sludge foaming

Area: Environmental Sciences

Cultural and Ideological Clashes in the Context of Built Environment
Author:
Anna P. Gawlikowska
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12 x
 

Abstract: The paper presented is a theoretical work discussing architecture as a standing testimony of human conflicts stemming from cultural and ideological clashes. The author describes several types of these clashes, starting with the discrepancies between history and modernity. The clash between the old and the new is portrayed as potentially triggering conflicts, in case there is no dialogue between history and contemporary architecture. Another type of conflicts is composed of those stemming from inadequate transposition of cultural norms, which may have a detrimental influence on human identity. Globalisation is shown as one of the factors that affect this loss of identity, and is reflected in architecture. In addition to that, the paper touches upon the issue of chaos vs. order, two notions used and understood differently by the practitioners of particular architectural styles. The antagonism between chaos and order is also described as generating potential conflicts. Finally, the paper discusses the ideology-based conflicts, reflected in architecture. They are described as closely related to the loss of human values, and the symbols of these values. Throughout the work, the author comments on positive and negative practices in culturally- and ideologically-sensitive architectural design, giving examples of projects and buildings, in different time periods.

Keywords: architecture, cultural conflicts, ideological conflicts, social clash, religious conflicts, identity, globalisation

Area: Civil Engineering, Urban Planning and Architecture

Towards the reuse of materials in Polish architecture. Working in the post-socialist context
Author:
Urszula Koźmińska
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10 x
 

Abstract: The article provides a discussion on how socialism, its aesthetics and architecture have influenced contemporary architecture in Poland, especially the choices of materials and aesthetics present in Polish society. The article focuses on current problems grounded in the socialist ideology, which can be seen as: the negations of socialism (e.g. denial of maintaining habits, homogenous aesthetics, temporary solutions), the remnants of the previous system (e.g. denial of natural, local, old materials) or the effects of westernization (e.g. the use of new, ‘luxurious’ materials). The post-socialist reality is a challenge for a sustainable approach to architecture and materials. This paper aims to analyse a specific, Polish context and to establish  guidelines for the future development of sustainable concepts and architectural applications of reused materials in architecture in Poland.

Keywords: reuse, reused materials, post-socialist architecture, sustainable architecture

Area: Civil Engineering, Urban Planning and Architecture

Kinetics of volatile fatty acids and hydrogen production during anaerobic digestion of organic waste material
Author:
Justyna Grzelak, Radosław Ślęzak, Liliana Krzystek
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11 x
 

Abstract: This paper describes the changes in volatile fatty acids and hydrogen production in time, during an anaerobic digestion process of organic waste material. The experiment showed that the reaction run most efficiently between 6 and 12th hour of the reaction time. This can be an indicator for future experiments on volatile fatty acids and hydrogen production optimisation.

Keywords: biopolymers, anaerobic digestion, VFA, hydrogen.

Area: Power Engineering

 
 
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