Wyniki wyszukiwania - BazTech

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Flak Tomasz, Paluch Jarosław, Gabor Jadwiga, Okła Hubert, Stanula Arkadiusz, Markowski Jarosław, Plich Jan, Swinarew Andrzej S.

Engineering of Biomaterials

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2020

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Vol. 23, no. 155

17--21

EN

The use of antibiotics to treat bacterial infections is becoming less and less effective year by year due to the increasing resistance of bacteria. The microbial evolutionarily acquired resistance to antibiotics increases the threat to man’s life due to difficulties regarding effective therapies to fight infections. Therefore, apart from treatment, it is necessary to introduce appropriate prophylaxis which limits the multiplication of bacterial colonies on everyday use objects. Due to the antibiotic resistance phenomenon, it is important to find a new material with antibacterial properties for FDM 3D printing in medical applications. The work contains research on a new chemical compound used as an additive to thermoplastics. The rhodamine derivative was synthesized via the 4-diphenylaminobenzaldehyde reaction with 1.3-indendione in a boiling mixture of EtOH/H2SO4. The obtained chemical compound was used as a bacteriostatic modifier of the polycarbonate (PC) properties, as such a modification enables application e.g. for medical device housings or for surfaces frequently touched by people. The modifier and the commercially available polymer were compounded with a high-temperature screw extruder and a filament for FDM 3D printer was created. The modified polymer revealed antibacterial properties relative to Escherichia coli and good thermal stability during the processing.

2

Badania znacznikowe hydrodynamiki komór osadu czynnego

Janiak K., Knap M., Balbierz P., Dobryszycki P.

Gaz, Woda i Technika Sanitarna

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2013

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Nr 1

33--38

PL

Hydrodynamika reaktorów osadu czynnego jest jednym z najważniejszych czynników warunkujących skuteczną pracę bloku biologicznego. Jedną z metod oceny dynamiki mieszania i transportu cieczy w reaktorach są badania znacznikowe. W artykule przedstawiono metodykę, wyniki oraz interpretację wstępnych testów znacznikowych przeprowadzonych z wykorzystaniem Rodaminy В w komorach beztlenowych komunalnej oczyszczalni ścieków w Lesznie (RLM 80 000). Uzyskane wyniki pokazują, iż reżim mieszania w badanych komorach jest zbliżony do idealnego reaktora o pełnym wymieszaniu, jednak obserwuje się krótkie spięcie pomiędzy dopływem i odpływem, a rzeczywisty czas przetrzymania jest o około 10-15% krótszy od teoretycznego. W artykule przedstawiono również metody doboru modelu zastępczego.

EN

Hydrodynamics of activated sludge reactors is one of the most important factors influencing its effectiveness. One of methods used to assess dynamics of fluid mixing and transport are tracer studies. In article methodology, results and interpretation of preliminary tracer tests (Rhodamine В as the tracer) conducted at Leszno WWTP (80 000 p.e) are presented. Obtained results shows that tested reactors behave almost like ideal completely stirred reactors with short circuits and hydraulic retention time 10-15 % lower than theoretical (T=V/Q). Article presents also methods of hydraulic model selection.

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Influence of selected fluorescent dyes on small aquatic organisms

Rowiński P.M., Chrzanowski M.M.

Acta Geophysica

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2011

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Vol. 59, no. 1

91-109

EN

Rhodamine B and Rhodamine WT are fluorescent dyes commonly used as tracers in hydrological investigations. Since introducing intensely red substances into rivers raises understandable doubts of ecological nature, the authors aimed at examining the influence of these dyes on small water fauna using bioindication methods. Quantitative results, calculated with the use of Bliss-Weber probit statistical method, were achieved by means of standardized ecotoxicological tests containing ready-to-hatch resting forms of fairy shrimp (Thamnocephalus platyurus). Qualitative studies included observation of water flea crustacean (Daphnia magna) and horned planorbis snail (Planorbis corneus), both typically present in rivers and representative for temperate climate, as well as guppy fish (Poecilla reticulata), paramecium protozoan (Paramaecium caudatum) and the above-mentioned fairy shrimp. The investigation revealed that both dyes in concentrations used for hydrological purposes are low enough to exert almost no toxic impact on water fauna considered.

4

Excited-state Solvation of Rhodamines: Dielectric and Specific Contributions

Ferreira J. A. B., Costa S. M. B.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 4

893-899

EN

Primary to tertiary amine based compounds of the form 9'-(2-ester-carbonyl)-phenyl- 3',6'-bis-(amino)-xanthylium) are studied as models for this class of compounds as regards the S1S0 shifts in solution. The magnitude of the solvatochromic shift decreases from primary amine to tertiary amine rhodamine chromophore. Primary aminoxanthylium spectral energy at maximum absorption decreases with the solvent electronic polarization whilst it increases with the orientational polarization function, suggesting extensive reorientation in the dipolar moment upon S1S0 excitation. By contrast, upon electronic excitation smaller dipolar moment variations are found in N-alkyl rhodamines, respectively with secondary and tertiary amine groups. Primary and secondary amine rhodamines' NH groups establish strong interactions with electron rich atomic centers of solvent molecules increasing the electronic stabilization energy.

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Flow injection chemiluminescence determination of polyhydroxy phenols in the presence of rhodamine B as a sensitiser

Lv Y., Zhang Z., He D., Hu Y.

Chemia Analityczna

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2003

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Vol. 48, No. 6

959-966

EN

A novel flow injection chemiluminescence (CL) system for determination of polyhydroxy phenols, including phloroglucinol, pyrogallol, resorcinol and pyrocatechol has been described. The system utilises CL reaction of ferricyanide with polyhydroxy phenols in sodium hydroxide media sensitised by the fluorescent dye Rhodamine B. The proposed procedure has a linear range of 0.05-5.0 ng ml/' for phloroglucinol, and 0.01-1.0 ug mL(-1) for pyrogallol, resorcinol and pyrocatechol. The method is sensitive, simple, and fast. The chemiluminescence reaction mechanism has been also proposed and briefly discussed.

PL

Opisano nową metodę analizy wstrzykowej z wykorzystaniem chemiluminescencji (CL) do oznaczania wielowodorotlenowych fenoli, włączając w to floroglucynę, pirogalol, rezor-cynę i pirokatechinę. Metoda jest oparta na chemiluminescencyjnej reakcji żelazocyjanku z fenolami wielowodorotlenowymi w środowisku wodorotlenku sodowego, sensybilizowanej za pomocą fluorescencyjnego barwnika rodaminy B. Procedura charakteryzuje się liniowym zakresem oznaczania: 0,05-5,0ug mL(-1) dla floroglucyny oraz 0,01-1,0 ug mL(-1) dla piro-galolu, rezorcyny i pirokatechiny. Metoda jest czuła, prosta i szybka. Przedsykutowano pokrótce możliwy mechanizm reakcji chemiluminescencyjnej.

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Spectrophotometric determination of zinc in soils and sediments with 5,7-diiodo-8-hydroxyquinoline and rhodamine 6G

Nair S., Biju V. M., Vijayalakshmy B., Rao T.P.

Chemia Analityczna

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2001

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Vol. 46, No. 4

589-596

EN

A method is described based on the selective extraction of zinc-5,7-diiodo-8-hydroxy-quinoline-rhodamine 6G ternary ion-association complex into toluene. Zinc contents as low as 0.005-0.15 pprn in soil and sediment samples can be readily determined. The relative standard deviation for 10 replicate measurements of Zn at a level of 0.025 ppm is 1.34%.

PL

Opisano metodę selektywnej ekstrakcji toluenem trójskładnikowego kompleksu jono-wo-asocjacyjnego Zn-5,7-dijodo-8-hydroksychinolina-rodamina 6G. Metoda nadaje się. do oznaczania małych ilości cynku (0.005-0.15 ppm) w próbkach gleby i osadów w zbiornikach wodnych. Względne odchylenie standardowe dla ilości 0.025 ppm i n =1O wynosi 1.34%.

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Spectrophotometric determination of vanadium(V) with 5,7-dichlorooxine nad Rhodamine 6G

Varma R. L., Reddy M. L. P., Rao T.P.

Chemia Analityczna

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2000

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Vol. 45, No. 5

745-750

EN

A selective method is described for the determination of 0.5-15 ug of vanadium(V) present in 50 ml based on the extraction of ternary ion-association complex formed by reacting vanadium(V) with 5,7-dichlorooxine and Rhodamine 6G. The method is highly sensitive (e = 6.12 x 104 1 mol(-1) cm(-1) at 516 nm). Very few ions interfere in the above determination which can be overcome by the addition of fluoride, citrate and thiourea. The developed method is precise and reliable. This was proved determining V(V) in certified reference material.

PL

Opisano selektywną metodę oznaczania wanadu(V) w zakresie od 0.5 do 15 ug w 50 ml. Polega ona na ekstrakcji toluenem trójskładnikowego kompleksu asocjacyjnego powstającego w reakcji z 5,7-dichlorooksynąi Rodamią 6G. Metoda jest bardzo czuła, molowy współczynnik absorpcji wynosi 6.12 x 10(-4)10 mol(-1) cm(-1) przy Lambda = 516 nm. Bardzo niewiele jonów zakłóca oznaczenie i mogą być one maskowane dodatkiem fluorku, cytrynianu i tiomocznika. Opracowana metoda jest precyzyjna i dokładna co potwierdzono oznaczaniem wanadu(V) w certyfikowanym materiale referencyjnym.