PL
 |
EN
Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 8

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
1
Content available Pervaporation applied for dewatering of reaction mixture during esterification
Krasiński A., Grudzień A., Wierzba P., Hajmowicz H., Zawada K., Synoradzki L.
Chemical and Process Engineering
|
2016
|
Vol. 37, nr 1
121--131
EN
In this work the esterification of diethyl tartrate was studied. The research was focused on the enhancement of reversible reaction yield, which is accomplished by dewatering of the reaction mixture. The removal of water shifts the equilibrium towards the main product. Pervaporation was applied for this purpose, and results were compared to distillation. The advantages and limitations of both processes are discussed. The experimental part consists of dewatering of mixture after the reaction had reached the equilibrium, and was subsequently fed to the test rig equipped with a single zeolite membrane purchased from Pervatech B.V. Results show a significant conversion increase as a result of water removal by pervaporation. Compared to distillation no addition of organics is necessary to efficiently remove water above the azeotrope. Nevertheless, some limitations and issues which call for optimisation are pointed out. A simple numerical model is proposed to support design and sizing of the pervaporation system. Various modes of integrated system operation are also briefly discussed.
2
Content available Spin trapping studies of essential oils in lipid systems
Makarova K., Drązikowska K., Suska B., Zawada K., Wawer I.
Nukleonika
|
2015
|
Vol. 60, No. 3, part 1
461--468
EN
In the present work, we report the results of a spin trapping ESR study of four essential oils widely used for skin care products such as creams and bath salts. The studied essential oils are Rosmarini aetheroleum (rosemary), Menthae piperitae aetheroleum (mint), Lavandulae aetheroleum (lavender), and Thymi aetheroleum (thyme). Fenton reaction in the presence of ethanol was used to generate free radicals. The N-tert- -butyl-α-phenylnitrone (PBN) was used as a spin trap. In the Fenton reaction, the rosemary oil had the lowest effect on radical adduct formation as compared to the reference Fenton system. Since essential oils are known to be lipid soluble, we also conducted studies of essential oils in Fenton reaction in the presence of lipids. Two model lipids were used, namely 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and 1,2-dipalmitoyl-sn- -glycero-3-phosphocholine (DPPC). The obtained results suggested that in the presence of DOPC lipids, the •OH and PBN/•CHCH3(OH) radicals are formed in both phases, that is, water and lipids, and all the studied essential oils affected the Fenton reaction in a similar way. Whereas, in the DPPC system, the additional type of PBN/X (aN = 16.1 G, aH = 2.9 G) radical adduct was generated. DFT calculations of hyperfi ne splittings were performed at B3LYP/6-311+G(d,p)/EPR-II level of theory for the set of c-centered PBN adducts in order to identify PBN/X radical.
3
Content available Oxidative stability of the lipid fraction in cookies : the EPR study
Zawada K., Kozłowska M., Żbikowska A.
Nukleonika
|
2015
|
Vol. 60, No. 3, part 1
469--473
EN
Cookies are a group of convenient food products that are popular among consumers. They may contain high amounts of fats, which can be prone to oxidation. To retard the oxidative deterioration, synthetic and natural antioxidants may be added. Herb and spice extracts can be sources of natural biologically active substances with antioxidant activity. In this work, electron paramagnetic resonance spectroscopy was used to monitor the lipid oxidation in cookies with rosemary and thyme extracts subjected to the storage in elevated temperature. It was shown that thyme extract can be used as a natural antioxidant source for the preparation of bakery products, while the rosemary extract should be used with care in fat-rich products exposed to high temperatures.
4
Content available Conceptual prototype of USB wireless adapter
Wodo W., Hanzlik L., Zawada K.
Challenges of Modern Technology
|
2014
|
Vol. 5, no. 4
8--11
EN
In this paper we investigate the issue of wireless USB hubs. Our aim is to adapt any USB device to its wireless version. We propose a minimized mobile hardware solution in the form of an electronic device and software allowing remote usage of peripherals such as keyboards, mice, USB sticks, etc. On the U.S. market similar solutions are known, but they are based on a many-to-one communication model and their design does not encourage mobility. With these designs peripheral devices still have one common point (in this case a hub instead of a computer). Additionally, hubs need external power supplies, thus they are connected to the grid by cable. Our solution is based on a one-to-one communication model and have a few key advantages for mobility. First, there is the possibility of minimizing the device itself and shortening the wire of the corresponding peripheral. Furthermore power consumption of the transmitter is much lower, and therefore there is no need to use an external power supply.
5
Content available remote Wartości i możliwości wykorzystania terenów poprzemysłowych rejonu Olkusza
Zawada K.
Czasopismo Techniczne. Architektura
|
2007
|
R. 104, z. 7-A
153-158
PL
W niniejszym artykule poruszono problemy związane z wpływem działalności przemysłowej na środowisko w rejonie Olkusza oraz przedstawiono działania podejmowane w celu poprawy jakości zdegradowanego środowiska przyrodniczego. Wskazano też na potrzebę interdyscyplinarnego spojrzenia na problem sposobu rekultywacji poprzemysłowych terenów, z zachowaniem wartości kulturowych i tożsamości omawianego regionu.
EN
The article tackles the question of the influence of industrial activity on the natural environment of Olkusz Region and the actions undertaken to improve the quality of the degraded natural environment. Furthermore, it points at the need for an interdisciplinary analysis of the problem of the means and methods of reclamation of post-industrial areas, with respect for cultural values and identity of the region in question.
6
Content available remote Wykorzystanie funduszy Unii Europejskiej w małych miastach poprzemysłowych - na wybranych przykładach
Zawada K.
Czasopismo Techniczne. Architektura
|
2006
|
R. 103, z. 12-A
322-329
PL
Od momentu przystąpienia Polski do Unii Europejskiej nastąpił wzrost liczby działań zmierzających do pozyskiwania funduszy na podnoszenie jakości przestrzeni małych miast poprzemysłowych. W artykule, na przykładzie wybranych małych miast południowej Polski, zostały zilustrowane działania władz lokalnych w celu pozyskania dofinansowania z funduszy Unii Europejskiej na różnorodne projekty. Na podstawie przedstawionych wzorcowych miast można stwierdzić, że zrealizowane inwestycje różnorodnie wpływają na strukturę miasta i jego otoczenie. W większości przypadków są to działania liniowe oraz punktowe, zazwyczaj poprawiające infrastrukturę techniczną miasta. Nieliczne są natomiast projekty kompleksowe, które mogą poprawić jakość przestrzeni w mieście oraz stymulujące wpłynąć na perspektywiczny rozwój regionu.
EN
Since Poland's access to EU an increase of number of activities aiming at gaining funds for improving quality of small post-industrial towns' space may be noticed. In the article the measures taken by local governments to raise the funds for various projects have been presented on chosen examples of small southern towns. Those models allow a conclusion that realised investments may diversely influence the town's structure and surroundings. Most measures were of linear or point type usually improving technical infrastructure of the town, while few were comprehensive measures which may improve the quality of town's space and stimulate region's development.
7
Content available remote Możliwości wykorzystania funduszy unijnych dla rewitalizacji zdegradowanych obszarów poprzemysłowych
Zawada K.
Czasopismo Techniczne. Architektura
|
2005
|
R. 102, z. 2-A
291--300
EN
One of the aims of ZPORR is vivacity and social attractiveness as well as development of touristic and cultural potential of the structures and grounds in the state of degradation. Not only is the increase of attractiveness of these areas aiming at economic development but also creating new posts, taking care of natural environment and, probably above all, preserving natural heritage which forms the identity of a place, possibility to identify, recognize it unmistakably. Actions related to projects supported with EU funds concern, among other, grounds where industrial activity has been ceased or is residual. Krakow has such valuable areas which wait to be brought back to life. The grounds of Zakłady im. L. Zieleniewskiego and adjacent former military grounds are examples of this. Is it possible to revitalise them? How to transform them so as to preserve their identity and to increase their economic and investment attractiveness?
8
Content available remote Fundusze unijne a problem restrukturyzacji miast poprzemysłowych na wybranych przykładach
Zawada K.
Czasopismo Techniczne. Architektura
|
2005
|
R. 102, z. 15-A
164--174
PL
W sytuacji, kiedy nastąpiło wyeksploatowanie zasobów surowcowych, branże przemysłu sektorów tradycyjnych popadły w poważne trudności gospodarcze, w wielu miastach opartych na działalności jednego, dwóch dużych zakładów przemysłowych obserwuje się brak impulsów podtrzymujących dalszy rozwój miasta. Autor pokazuje na dwóch przykładach obecną sytuację miast poprzemysłowych, problemy, starania zmierzające do wykorzystania funduszy celowych na restrukturyzację miast, różnorodne działania zmierzające do powstania nowych miejsc pracy, poprawy środowiska naturalnego czy działania podnoszące jakość zdegradowanej przestrzeni. Autor dochodzi do konkluzji, że istnieje ogromna potrzeba restrukturyzacji i ożywienia gospodarczego miast poprzemysłowych, a realizacja zadań z tym związanych jest skomplikowana, długotrwała i bardzo kosztowna.Możliwość pozyskiwania wsparcia finansowego z funduszy europejskich jest pewną szansą, jednakże programy dotyczące rewitalizacji powinny obejmować zarówno sferę ekonomiczną, przestrzenno-funkcjonalną, kompozycyjną, ekologiczną, jak i społeczną.
EN
As all the resources have been exploited, industrial branches of traditional sectors fell into economic difficulties and in numerous towns based on one or two big industrial companies no impulses for further development may be noticed. The author presents on two examples the current situation of postindustrial towns, the problems and the efforts aiming at the use of the intentional funds in restructuring of cities various actions being taken to create new posts and to improve the natural environment or degraded space. The author draws the conclusion that there is great need for restructuring and economic revitalization of postindustrial towns and realization of the tasks connected with it will be very complex, long-lasting and very expensive. The possibility of gaining EU financial support is a chance, nevertheless the revitalization programmes should concern the spheres of economy, space and functionality, composition, ecology and sociology.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.