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1.
J Environ Manage ; 362: 121331, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38833931

RESUMO

This study introduces an innovative LED-IoT photoreactor, representing a significant advancement in response to the demand for sustainable water purification. The integration of LED-IoT installations addresses the challenge of intermittent sunlight availability, employing LEDs with a spectrum mimicking natural sunlight. Passive Infra-Red (PIR) sensors and Internet of things (IoT) technology ensure consistent radiation intensity, with the LED deactivating in ample sunlight and activating in its absence. Utilizing a visible light-absorbing photocatalyst developed through sol-gel synthesis and mild-temperature calcination, this research demonstrates a remarkable carbamazepine removal efficiency exceeding 95% under LED-IoT system illumination, compared to less than 90% efficiency with sunlight alone, within a 6-h exposure period. Moreover, the designed photocatalytic system achieves over 60% mineralization of carbamazepine after 12 h. Notably, the photocatalyst demonstrated excellent stability with no performance loss during five further cycles. Furthermore, integration with renewable energy sources facilitated continuous operation beyond daylight hours, enhancing the system's applicability in real-world water treatment scenarios. A notable application of the LED-IoT system at an operating sewage treatment plant showed nearly 80% efficiency in carbamazepine removal from sewage in the secondary settling tank after 6 h of irradiation, coupled with nearly 40% mineralization efficiency. Additionally, physicochemical analyses such as XPS and STA-FTIR confirm that the carbamazepine photooxidation process does not affect the surface of the photocatalyst, showing no adsorption for degradation products.


Assuntos
Carbamazepina , Energia Solar , Poluentes Químicos da Água , Purificação da Água , Carbamazepina/química , Carbamazepina/isolamento & purificação , Purificação da Água/métodos , Poluentes Químicos da Água/química , Luz Solar , Eliminação de Resíduos Líquidos/métodos , Catálise
2.
Molecules ; 27(19)2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36235101

RESUMO

Polyphenols, organic acids and metal ions are an important group of compounds that affect the human health and quality of food and beverage products, including wines. It is known that a specific correlation between these groups exist. While wines coming from the New World and the Old World countries are extensively studied, wines coming from cool-climate countries are rarely discussed in the literature. One of the goals of this study was to determine the elemental composition of the wine samples, which later on, together as polyphenols and organic acids content, was used as input data for chemometric analysis. The multivariate statistical approach was applied in order to find specific correlations between the selected group of compounds in the cool-climate wines and the features that distinguish the most and differ between red and white wines and rosé wines. Moreover, special attention was paid to resveratrol and its correlation with selected wine constituents.


Assuntos
Vinho , Ácidos/análise , Humanos , Metais/análise , Compostos Orgânicos/análise , Polifenóis/análise , Resveratrol/análise , Vinho/análise
3.
Med Sci Monit ; 27: e935438, 2021 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-34759258

RESUMO

Medical Science Monitor is retracting the following publication on the basis of duplicated published content. 1) Kubaszewski L, Ziola-Frankowska A, Frankowski M, Rogala P, Gasik Z, Kaczmarczyk J, Nowakowski A, Dabrowski M, Labedz W, Miekisiak G, Gasik R. Comparison of trace element concentration in bone and intervertebral disc tissue by atomic absorption spectrometry techniques. J Orthop Surg Res. 2014 Oct 25;9: 99. doi: 10.1186/s13018-014-0099-y. PMID: 25342441; PMCID: PMC4220064. 2) Kubaszewski L, Ziola-Frankowska A, Frankowski M, Nowakowski A, Czabak-Garbacz R, Kaczmarczyk J, Gasik R. Atomic absorption spectrometry analysis of trace elements in degenerated intervertebral disc tissue. Med Sci Monit. 2014 Nov 4;20: 2157-64. doi: 10.12659/MSM.890654. PMID: 25366266; PMCID: PMC4301216. 3) Nowakowski A, Kubaszewski L, Frankowski M, Wilk-Franczuk M, Ziola-Frankowska A, Czabak-Garbacz R, Kaczmarczyk J, Gasik R. Analysis of trace element in intervertebral disc by Atomic Absorption Spectrometry techniques in degenerative disc disease in the Polish population. Ann Agric Environ Med. 2015;22(2): 362-7. doi: 10.5604/12321966.1152096. PMID: 26094540. We have reviewed the content of all three similar publications. We note that Medical Science Monitor was the second to publish this study, in November 2014. At that time, the Corresponding Author gave no declaration of submitting this study to any other journal, nor of previously publishing this study. Reference: Lukasz Kubaszewski, Anetta Ziola-Frankowska, Marcin Frankowski, Andrzej Nowakowski, Róza Czabak-Garbacz, Jacek Kaczmarczyk, Robert Gasik. Atomic Absorption Spectrometry Analysis of Trace Elements in Degenerated Intervertebral Disc Tissue. Med Sci Monit, 2014; 20: 2157-2164. DOI: 10.12659/MSM.890654.

4.
Molecules ; 26(20)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34684804

RESUMO

This paper presents a new method for the simultaneous speciation analysis of arsenic (As(III)-arsenite, As(V)-arsenate, DMA-dimethylarsinic acid, MMA-methylarsonic acid, and AsB-arsenobetaine) and selenium (Se(IV)-selenite, Se(VI)-selenate, Se-Methionine, and Se-Cystine), which was applied to a variety of seafood and onion samples. The determination of the forms of arsenic and selenium was undertaken using the High-Performance Liquid Chromatography Inductively Coupled Plasma Mass Spectrometry (HPLC-ICP-MS) analytical technique. The separation of both organic and inorganic forms of arsenic and selenium was performed using two analytical columns: an anion exchange column, Dionex IonPac AS22, containing an alkanol quaternary ammonium ion, and a double bed cation-anion exchange guard column, Dionex Ion Pac CG5A, containing, as a first layer, fully sulfonated latex for cation exchange and a fully aminated layer for anion exchange as the second layer. The ammonium nitrate, at pH = 9.0, was used as a mobile phase. The method presented here allowed us to separate the As and Se species within 10 min with a suitable resolution. The applicability was presented with different sample matrix types: seafood and onion.


Assuntos
Arsênio/análise , Contaminação de Alimentos/análise , Cebolas/química , Cebolas/toxicidade , Alimentos Marinhos/análise , Alimentos Marinhos/toxicidade , Selênio/análise , Animais , Intoxicação por Arsênico , Arsenicais/análise , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Humanos , Espectrometria de Massas , Compostos Organosselênicos/análise , Compostos Organosselênicos/toxicidade , Compostos de Selênio/análise , Compostos de Selênio/toxicidade
5.
Molecules ; 26(9)2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-34062968

RESUMO

The ozonation of aromatic compounds in low-pH water is ineffective. In an acidic environment, the decomposition of ozone into hydroxyl radicals is limited and insufficient for the degradation of organic pollutants. Radical processes are also strongly inhibited by halogen ions present in the reaction medium, especially at low pH. It was shown that even under such unfavorable conditions, some compounds can initiate radical chain reactions leading to the formation of hydroxyl radicals, thus accelerating the ozonation process, which is referred to as so-called "self-enhanced ozonation". This paper presents the effect of bromides on "self-enhanced ozonation" of benzoic acid (BA) at pH 2.5. It is the first report to fully and quantitatively describe this process. The presence of only 15 µM bromides in water inhibits ozone decomposition and completely blocks BA degradation. However, the effectiveness of this process can be regained by ozonation in the presence of phosphates or sulphate. The addition of these inorganic salts to the bromide-containing solution helps to recover ozone decomposition and BA degradation efficiency. As part of this research, the fractions of hydroxyl, sulphate and phosphate radicals reacting with benzoic acid and bromides were calculated.

6.
Molecules ; 25(5)2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32121003

RESUMO

Aluminum is very common in the natural environment and in everyday human life. We are living in the "aluminum age." Its average daily intake should not exceed a few mg/day. Unfortunately, despite the growing number of alarming data about the toxicity of this element, human exposure to aluminum is constantly increasing. The toxicity and bioavailability of aluminum depends mainly on the form in which it occurs. The main variables conditioning the form are the concentration, the type, the molar ratio of aluminum to ligand, the pH value, and the temperature. This research presents a new method for speciation analysis of both inorganic and organic aluminum complexes in model solutions by LC-ICP-MS. Different solutions with variable pH values and different Al/ligand molar ratios (fluorides and several organic ligands, e.g., citrates and oxalates ions) were used. The chromatographic separation process was carried out based on isocratic and gradient elution, using a cation exchange analytical column. All determinations have been confirmed based on chemical equilibrium modeling programs. The new developed method was successfully applied for the first time in speciation analysis of real samples: white and red wine.


Assuntos
Alumínio/química , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Vinho/análise , Alumínio/análise , Compostos de Alumínio/análise , Ácido Cítrico/análise , Fluoretos/análise , Concentração de Íons de Hidrogênio , Modelos Químicos , Ácido Oxálico/análise
7.
Molecules ; 23(11)2018 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-30463175

RESUMO

This paper presents the results of determination of hazardous metal (Cd, Cu, Cr, Hg, Mn, Ni, Pb, Zn) and metalloid (As, Sb) levels in toys available in the Polish market. Two independent sample preparation methods were used to determine the concentration and content of the metals and metalloids. The first one is defined by the guidelines of the EN-71 standard and undertook extraction in 0.07 mol/L HCl. This method was used to conduct speciation analysis of Cr(III) and Cr(VI), as well as for the determination of selected metals and metalloids. The second method conducted mineralization in a HNO3 and H2O2 mixture using microwave energy to determine the content of metals and metalloids. Determination of chromium forms was made using the high-performance liquid chromatography inductively coupled plasma mass spectrometry (HPLC-ICP-MS) method, while those of metals and metalloids were made using the ICP-MS technique. Additionally, in order to determine total content of chromium in toys, an energy dispersive X-ray fluorescence spectrometer (EDX) was used. The results of the analyses showed that Cr(VI) was not detected in the toys. In general, the content of heavy metals and metalloids in the studied samples was below the migration limit set by the norm EN-71.


Assuntos
Substâncias Perigosas , Metais Pesados/análise , Jogos e Brinquedos , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Saúde Pública/métodos , Espectrometria por Raios X , Oligoelementos/análise
8.
Molecules ; 23(11)2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30400672

RESUMO

Knowledge about the metal content of wine is very important, for many reasons. Depending on the element, its quantity varies in wine from ng/L to mg/L. Despite the fact that metals are not directly connected to the taste and aroma of the wine, their content should be determined and controlled, because excess is undesirable, and in some cases prohibited, due to potential toxicity. Several analytical procedures for metal determination are applied. However, due to sensitivity, low limit of detection and speed of analysis, inductively coupled plasma-mass spectrometry (ICP-MS) is one of the most frequently used techniques. The aim of this study was to reveal specific relationships between the wine samples or between the chemical variables in order to classify the wines according to their metal content by application of chemometric analysis. For metals content determination, two techniques, ICP-MS and inductively coupled plasma-optical emission spectrometry (ICP-OES), were applied. Data obtained showed that none of the wine samples surpassed the toxic levels reported for metals in the literature, thus, these wines appeared to be safe as regards the risk associated with the potentially toxic metals intake. However, specific correlations between metals and specific aspects of the wines themselves have been found.


Assuntos
Espectrometria de Massas , Metais/análise , Vinho/análise
9.
J Environ Sci (China) ; 65: 153-161, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29548386

RESUMO

The research presents the first results of aluminium speciation analysis in aqueous extracts of individual plant parts of Betula pendula and soil samples, using High Performance Ion Chromatography with Diode Array Detection (HPIC-DAD). The applied method allowed us to carry out a full speciation analysis of aluminium in the form of predominant aluminium-fluoride complexes: AlF(x=2,3,4)(3-x) (first analytical signal), AlF2+ (second analytical signal) and Al3+ (third analytical signal) in samples of lateral roots, tap roots, twigs, stem, leaf and soil collected under roots of B. pendula. Concentrations of aluminium and its complexes were determined for two types of environment characterised by different degree of human impact: contaminated site of the Chemical Plant in Lubon and protected area of the Wielkopolski National Park. For all the analysed samples of B. pendula and soil, AlF(x=2,3,4)(3-x) had the largest contribution, followed by Al3+ and AlF2+. Significant differences in concentration and contribution of Al-F complexes and Al3+ form, depending on the place of sampling (different anthropogenic pressure) and plant part of B. pendula were observed. Based on the obtained results, it was found that transport of aluminium is "blocked" by lateral roots, and is closely related to Al content of soil.


Assuntos
Alumínio/análise , Betula/química , Monitoramento Ambiental , Poluentes do Solo/análise , Alumínio/química , Cromatografia , Folhas de Planta/química , Raízes de Plantas/química , Solo/química , Poluentes do Solo/química
10.
J Sep Sci ; 39(18): 3482-7, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27422313

RESUMO

We present the development of a method for the simultaneous determination of inorganic nitrogen species in oxidized (NO2 (-) , NO3 (-) ) and reduced (NH4 (+) ) forms using ion chromatography with diode-array detection (205, 208, and 425 nm, respectively). The oxidized forms were determined directly after the separation in the anion exchanger, while the reduced form was determined in the column hold-up time after derivatization with the Nessler reagent. The use of an appropriate modifier (Seignette reagent) and mobile phase (NaCl) enabled the determination of inorganic nitrogen species in highly salinated environmental samples (water, sediments). Moreover, low detection limits were obtained of 0.04 mg/L for NH4 (+) and 0.006 and 0.005 mg/L for NO2 (-) and NO3 (-) , respectively. The analysis of environmental samples indicated NH4 (+) contents of up to 1161 ± 47 mg/kg and NO3 (-) of up to 148 ± 6 mg/kg for sediment samples, as well as the NH4 (+) concentrations of up to 0.98 ± 0.10 mg/L, NO2 (-) of up to 24 ± 1 mg/L and NO3 (-) of up to 20 ± 1 mg/L for water samples.

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