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1

Determination of organochlorine pesticides in water using GC combined with dispersive solid-phase extraction with single-walled carbon nanotubes

Sun Peng, Cui Yanhong, Yan Rui, Lian Yongfu

Acta Chromatographica

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2021

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Vol. 33, no. 2

202--207

EN

In this study, single-walled carbon nanotubes (SWNTs) were used to determine organochlorine pesticides (chlorothalonil and pentachloronitrobenzene) in water using dispersive solid-phase extraction (DSPE), followed by gas chromatography (GC). The optimal adsorption conditions were determined by analyzing the effect of adsorbent dosage, adsorption time, eluent type and volume, and elution time. Under the optimal conditions, a good linearity was obtained at concentrations from 10 to 400 μg L−1 with correlation coefficients ranging from 0.9991 to 0.9986. The limits of detection (LOD) for the two organochlorine pesticides were 0.025 and 0.049 μg L−1, and the limits of quantification (LOQ) were 0.080 and 0.156 μg L−1, respectively. The accuracy of the proposed method was evaluated by measuring the recovery of the spiked samples, which ranged from 82.5% to 110.5% at spiking levels of 0.5–10 μg L−1 with relative standard deviations lower than 5.6% (n = 6). This method was successfully applied to determine the target analytes in canal water, drinking water, and water taken from the inlets and outlets of a wastewater treatment plant. The results demonstrate that the developed method has great potential for determining the two organochlorine pesticides in water samples.

2

Occurrence of Cryptosporidium, Giardia and Toxoplasma in surface waters in the area of Cracow

Polus M., Kocwa-Haluch R.

Environment Protection Engineering

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2014

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Vol. 40, nr 2

105--113

EN

Despite some knowledge on the risks from exposure to intestinal parasitic protozoa such as Cryptosporidium, Giardia and Toxoplasma, no occurrence studies of these protozoa were conducted in Cracow area. Therefore, the purpose of the work was to examine the presence of Cryptosporidium, Giardia and Toxoplasma in surface water samples including intakes and recreational waters. The study showed that the vast majority of water samples were positive for Cryptosporidium sp., and some of the samples were positive for Giardia intestinalis. None of the tested water samples showed the presence of Toxoplasma. Given the limitations of the research methods used and the limits of detection, these results indicated that the concentration of protozoan cysts/oocysts may range from <1 to dozens oocysts/cysts per liter of water. These concentrations are comparable to the values given in reports of major worldwide outbreaks of cryptosporidiosis or giardiasis, which indicating a need to further investigate Cracow's surface waters.

3

Polimery z odciśniętą cząsteczką - selektywne sorbenty do izolowania związków estrogennych

Sadowski R., Gadzała-Kopciuch R., Buszewski B.

Analityka : nauka i praktyka

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2014

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nr 2

4--8

4

Stosowanie zasad "zielonej chemii" w metodykach oznaczania pozostałości pestycydów w próbkach wody

Tankiewicz M., Fenik J., Biziuk M.

Analityka : nauka i praktyka

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2013

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nr 1

48--53

PL

Nieustanny wzrost zużycia pestycydów powoduje, że w większych ilościach przedostaja się one do środowiska wodnego. Stanowi to źródło narażenia zdrowia i życia nie tylko ludzkiego, lecz wszytskich organizmów żywych. Oprócz stosowania technik bezrozpuszczalnikowych dominującym trendem w przygotowaniu próbek, zgodnie z zasadami "zielonej chemii", jest także miniaturyzacja i automatyzacja technik.

5

Gas chromatographic determination of parabens after in-situ derivatization and dispersive liquid-liquid microextraction

Prichodko A, Janenaite E, Smitiene V, Vickackaite V.

Acta Chromatographica

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2012

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Vol. 24, no. 4

589--601

EN

Dispersive liquid-liquid microextraction in combination with an in situ derivatization is suggested for parabens sampling and preconcentration. The derivatization was carried out with acetic anhydride under alkaline conditions maintained using di-potassium hydrogen phosphate. The effects of an extraction solvent type, extraction and disperser solvents volume, extraction time, and ionic strength of the solution on the extraction efficiency were investigated. Chlorobenzene containing n-hexadecane as internal standard was used as an extracting solvent and acetone was used as a disperser solvent. The calibration graphs were linear up to 10 mg mL-1, correlation coefficients were 0.997–0.999, enrichment factors were from 70 for methylparaben to 210 for butylparaben, and detection limits were 22, 4.2, 3.3, and 2.5 µg L−1 for methylparaben, ethylparaben, propylparaben, and butylparaben, respectively. Repeatabilities of the results were acceptable with relative standard deviations up to 11%. A possibility to apply the proposed method for parabens determination in water samples was demonstrated.

6

Development of a new kinetic spectrophotometric method for determination of Mn(II) in natural waters

Igov A.R., Simonovic R. M., Pecev T. G., Pecev E.T.

Chemia Analityczna

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2009

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Vol. 54, No. 2

247-256

EN

A new kinetic method for determination of traces of Mn(II) has been developed. The method is based on the catalytic effect of Mn(II) on the oxidation of trimethylenediamine-N,N,N',N'--tetra acetic acid (TDTA) by KMnO4 in acid media. Under optimal conditions the limit of determination of Mn(II) was 0.5 ng mL-1. The probable relative error was 4.0-2.8% in . the concentration range of Mn(II) 1.0-5.0 ng mL-1. Limit of detection was 0.12 ng mL-1. The effects of certain foreign ions upon the reaction rate were determined in order to assess selectivity of the method, which was found relatively good. Kinetic equations for the investigated process were proposed. The method has been applied to the determination of Mn(II) ' in natural water.

PL

Opracowano nową, kinetycznąmetodę oznaczania śladowych ilości Mn(II), wykorzystującą , katalityczny wpływ Mn(II) na utlenianie kwasu trimetylenodiamino-N,N,N',N-tetraoctowego (TDTA) w środowisku kwaśnym. W optymalnych warunkach granica oznaczalności Mn(II) wynosiła 0,5 ng L-1. Prawdopodobny błąd względny zawierał się w granicach 4,0-2,8% przy stężeniu Mn(II) od 1,0 do 5,0 ng L-1. Granica wykrywalności wynosiła 0.12 ng L-1. Metoda odznacza się dobrą selektywnością, co stwierdzono badając wpływ innych jonów na szybkość reakcji. Zaproponowano równania kinetyczne opisujące badany proces. Metodę zastosowano do oznaczania zawartości Mn(ll) w naturalnych zbiornikach wodnych.

7

Comparison of selected methods of preparation water samples for analysis of trace elements

Rajkowska M., Lidwin-Kaźmierkiewicz M., Antonowicz J.

Chemia i Inżynieria Ekologiczna

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2007

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Vol. 14, nr 12

1255-1260

EN

The aim of this work was to compare selected methods of preparing water samples for analysis of trace elements: Al, Cd, Cr, Cu, Fe, Li, Mn, Ni, Pb, V and Zn. Four methods were compared: two standard methods EPA 3015A and EPA 200.7 and also two modifications of the EPA 3015 A method. In the first modification the samples of water were concentrated by evaporation in Kjeldahl flasks and in the second method by lyophilization. The efficiency of analysis was verified by method of standard addition. In the method of concentration of water in Kjeldahl flasks and also, in the method of lyophilization of the water samples, the obtained results: (100 š 15 %) indicate high efficiency of both methods. In the standard methods, the results were lower than those in the modified methods.

PL

Celem tej pracy było porównanie wybranych metod przygotowania próbek wody do oznaczania pierwiastków śladowych: Al, Cd, Cr, Cu, Fe, Li, Mn, Ni, Pb, V, Zn. Wybrano cztery metody: dwie standardowe EPA 301SA i EPA 200.7, a także dwie modyfikacje metody EPA 301SA. Pierwsza modyfikacja polegała na zagęszczaniu próbek wody poprzez odparowywanie w kolbach Kjeldahla, w drugiej metodzie zastosowano liofilizację. Efektywność analiz była weryfikowana metodą dodatku wzorca. W metodzie zagęszczania wody w kolbach Kjeldahla, a także w metodzie z zastosowaniem liofilizacji uzyskano wyniki w granicach (100 š 15 %), co wskazuje na dużą skuteczność tych metod. W metodach standardowych otrzymano wyniki mniej zadowalające.

8

Voltammetric determination of thallium in water and plant material

Krasnodębska-Ostręga B., Stryjewska E.

Chemia Analityczna

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2004

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Vol. 49, No. 4

519-526

EN

Differential pulse anodic stripping voltammetry with a hanging mercury drop electrode was applied for the determination of thallium in wastewater and horseradish samples collected in highly contaminated region. To decompose the organic matter in water samples, the UV irradiation was employed. The digestion of the plant material was conducted with a HNO(3)/HClO(4) mixture using the microwave decomposition under elevated pressure. Thallium determinations were carried out in the presence of DTPA as a complexing agent. The detection limit was equal to 0.7 ng ml/1. The interference of Cd and Pb was also studied. The proposed method was validated using the reference materials and the inter-method comparison (ICP-MS).

PL

Metodę pulsowej różnicowej woltamperometrii inwersyjmej na HMDE zastosowano do oznaczania talu w próbkach środowiskowych (wody odpadowe i korzeń chrzanu) pochodzących z regionu o wysokim stopniu skażenia. Próbki wód przed oznaczeniami naświetlano promieniowaniem UV, a materiał roślinny poddany został rozkładowi za pomocą mieszaniny HNO(3) i HClO(4) przy użyciu mikrofal w warunkach podwyższonego ciśnienia. Elektrolit podstawowy zawierał DTPA jako czynnik kompleksujący. Granica oznaczalności metody wynosi 0.7 ng ml/1. Zbadano także wpływ obecności jonów Cd i Pb. Walidację zaproponowanej procedury analitycznej przeprowadzono przy użyciu materiału odniesienia oraz poprzez porównanie uzyskanych wyników z wynikami otrzymanymi metodą ICP-MS.

9

Determination of total phosphorus in water samples by flow-injection analysis

Zhang J. F., Wang X. R., Shen H., Wu J. C., Xue Y. Q.

Chemia Analityczna

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2004

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Vol. 49, No. 4

527-533

EN

A new colorimetric-FIA method for the determination of total phosphorus in water samples has been described. For the purpose of the above analysis the newly invented constant micro-flux mixing pumps, as well as the PLC (industrial programmable controller) manipulator and IOP (intelligent operation panel) were used to simplify the procedure. The proposed method allowed one to determine total phosphorus in the concentration range: 0.02-0.50 mg L-1, with a detection limit of 0.005 mg L-1. The analysis required only 4 min to be completed. The proposed method is suitable for the automated and continuous analysis, and was successively applied to the determination of total phosphorus in wastewater samples.

PL

Opisano nową, jednościeżkową metodę kolorymetryczno-przepływową do oznaczania całkowitego fosforu w próbkach wody. Do tego celu skonstruowano pompy mieszające o stałym mikrostrumieniu oraz przemysłowy, programowany kontroler i inteligentny panel operacyjny do manipulacji i przeliczeń. Całkowity fosfor można oznaczać w zakresie 0,02-0,5 mg L(-1), granica wykrywalności wynosi 0,005 mg L(-1). Całkowity czas oznaczania wynosi 4 min. Proponowana metoda nadaje się do analizy automatycznej i ciągłej. Została zastosowana do oznaczania całkowitego fosforu w ściekach.

10

A new passive sampler as an alternative tool for monitoring of water pollutants

Kot-Wasik A.

Chemia Analityczna

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2004

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Vol. 49, No. 5

691-705

EN

By using a passive sampler for a long sampling period, it is possible to monitor the pollutant concentration in time. In this paper such an approach has been applied to some organic pollutants in water. A new passive sampler has been designed and examined. After exposing the passive sampler to the pollutants for a certain period of time (varied from days to weeks), its solvent filling was subjected to the analysis by liquid chromatography for the content of these pollutants. The sorption of the analytes took place in 50 L-in-volume containers with water of the known concentration of the selected organic pollutants. Investigations were focused on e phenol-type compounds, some pesticides and herbicides. Several parameters were found to strongly influence the performance of the passive method, i.e. the uptake of the pollutants through different membranes, the filling solvents, and the exposure time in various environments.

11

Istotne błędy i sposoby ich minimalizowania w procedurach analitycznych próbek wody

Barałkiewicz D.

LAB Laboratoria, Aparatura, Badania

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2002

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R. 7, nr 4

20-22

PL

Jakość wyniku analitycznego nie jest jakimś wyimaginowanym ideałem, ale zależy od konkretnych wymagań narzuconych analitykowi przez zleceniodawcę. Aby analityk mógł zapewnić odpowiednią jakość wyniku analitycznego, powinien być choć częściowo zorientowany w problematyce, która dotyczy zagadnienia będącego przedmiotem analizy.