Wyniki wyszukiwania - BazTech

1

Nanohydrogels based on self-assembly of cationic curdlan and anionic hydroxypropylcellulose derivatives for piroxicam delivery

Lachowicz D., Kaczyńska A., Barnasik A., Karewicz A., Berent K., Zapotoczny S.

Engineering of Biomaterials

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2020

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Vol. 23, no. 158 spec. iss.

17

2

Chitosan-based nanocapsules of core-shell architecture

Szafraniec J., Odrobińska J., Lachowicz D., Kania G., Zapotoczny S.

Polimery

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2017

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T. 62, nr 7-8

509--515

EN

N-dodecyl derivative of cationically modified chitosan was used to prepare core-shell nanocapsules templated on liquid cores. Surfactant-free method based on ultrasound-assisted direct emulsification of aqueous solution of polysaccharide with oleic acid was applied. Formation of spherical capsules was confirmed by scanning and transmission electron microscopies. Dynamic light scattering measurements were used to determine physicochemical parameters of the obtained particles as well as to follow the process of multilayer shell formation. Confocal microscopy was applied to examine the ability of encapsulation of hydrophobic compounds inside the cores of the nanocapsules. Performed studies confirmed that hydrophobically modified cationic chitosan provides long-term stabilization of oil-in-water emulsion for biomedical applications as no toxic effect was observed in acute oral toxicity studies.

PL

Do przygotowania nanokapsuł na ciekłych rdzeniach stabilizowanych bez użycia małocząsteczkowych surfaktantów użyto N-dodecylowej pochodnej zmodyfikowanego kationowo chitozanu. Kapsuły otrzymano w procesie wspomaganej ultradźwiękami bezpośredniej emulsyfikacji fazy wodnej zawierającej modyfikowany polisacharyd oraz kwas oleinowy. Powstawanie sferycznych kapsuł potwierdzono za pomocą skaningowej oraz transmisyjnej mikroskopii elektronowej. Obrazowanie z użyciem mikroskopii konfokalnej posłużyło natomiast do zbadania zdolności do enkapsulacji hydrofobowych barwników w rdzeniach chitozanowych nanokapsuł. Stosując technikę dynamicznego rozpraszania światła wyznaczono fizykochemiczne parametry nanoemulsji oraz stwierdzono powstawanie wielowarstwowych otoczek. Przeprowadzone badania dowiodły, że zastosowanie hydrofobowo zmodyfikowanej kationowej pochodnej chitozanu pozwala na uzyskanie stabilnych w czasie emulsji typu olej w wodzie. Wykazany brak toksyczności układów w warunkach in vivo pozwala na ich zastosowanie do celów biomedycznych.

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Porównanie trwałości zmęczeniowej nadstopów niklu w postaci odlewanej klasycznie i krystalizowanej kierunkowo, przeznaczonych do budowy turbin gazowych

Lachowicz D.

Zeszyty Naukowe. Mechanika / Politechnika Opolska

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2014

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z. 104

97-100

EN

As the costs of structural materials are increasing, manufacturers reach to produce not only energy efficient but powerful engines to meet customer demand. Economics dictate a need of researching into new techniques of using older superalloy designs to achieve superior performance. This paper showcases a thermo-mechanical fatigue reliability comparison between well, established superalloys: IN-738LC and CM-247LC in either cast or directionally solidified form.

4

Laboratory study of effectiveness of sorbents intended for oil spill combating

Kończewicz W., Walaszkowska N., Lachowicz D., Otremba Z.

Journal of KONES

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2014

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Vol. 21, No. 4

247--254

EN

While various floating objects driven by combustion engines are exploited, unintentional oil spill might be done (caused by fuel, lubricant or gear leaks). So arisen undesirable pollution is usually removed from water environment using various types of booms, pumps and skimmers as well as by various oil-sorption materials. Sometimes oil spills are dispersed into bulk of water (only in water-areas that are rich with oil-consumption bacteria). The reason for undertaking investigations described in this paper was a real problem with oil pollution in narrow spaces of port and shipyard basins, marines and inland shipping routes. The paper describes study on sorptivity of chosen materials proposed as measures to combat oil spills on the water surface. Natural, synthetic and mineral materials were investigated at laboratory conditions, which was based on contacting those materials with, on the one hand, only water and – on the second hand – with oil in two ways, namely: with oil only and with oil as a film on the water surface. The authors presents in graphical form dependencies of sorptivity on a type of sorbent and on the time. In addition, air temperature, oxygen content in the water, density and viscosity oil are registered. The data obtained from the measurements play a role input data to establish procedure for usefulness of defines sorbent-materials in define conditions of application.

5

Study on oil sorbents effectiveness

Kończewicz W., Grabowska O., Lachowicz D., Otremba Z.

Journal of KONES

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2013

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Vol. 20, No. 1

135--138

EN

The paper presents search for objective and quantitative method of determination usefulness of various loose sorbents destined for cleaning surfaces polluted with oil. The motivation to take up the topic is that oil pollution emergence in marine areas remains still as the environmental problem. During the ship exploitation there is possibility of appearing of the fuel oil, lubricating oil, hydraulic oil or even transformer oil leaks on the board which might be erased by washing or using sorbent powders and granules or mates. In the case of disposing the washing liquids, the large volume of oil-in-water emulsion is forming which is gathered in a tank and further transported to the vessel cleaning system. In the case when sorbents are applied in an early phase of oil leakage, the vessel cleaning system is less overloaded which reduce the probability of failure. We report analyses of effectiveness of mineral and organic sorbents. The time-period of incepting of defined amount of oil by define amount of sorbent is applied as the sorption effectiveness parameter. Time plots of oil sorption as well as visualizations of this process are presented. Method to characterize the efficiency of sorbents in relation to used lubricating oil is proposed which will stand as the base for further works directed towards elaborating optimal sorbent-set which can be rapidly used for combat spillages and leaks of oils and even other liquid dangerous payloads carried by ships.

6

Narzędzia do monitoringu sieci osiedlowych

Kudzia P., Lachowicz D., Nowicki K.

Zeszyty Naukowe Wydziału ETI Politechniki Gdańskiej. Technologie Informacyjne

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2005

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T. 6

251-260

PL

Przedstawiono popularne narzędzia wykorzystywane do monitoringu sieci osiedlowych, dokonano ich klasyfikacji, porównania oraz oceny możliwości zastosowania w sieciach w zależności od ich rozmiarów. Zaprezentowano rozwiązanie autorskie - qStatus - uzupełniające możliwości dostępnych rozwiązań typu Open Source.

EN

Article shows study of requirements for monitoring software that can be used in Community Local Area Networks. Review and comparison of most popular, in authors opinion, Open Source solutions is presented. Also monitoring application - qStatus - written by authors is described.