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A new strategy for the combination of supramolecular liquid phase microextraction and UV–Vis spectrophotometric determination for traces of maneb in food and water samples Полный текст
2021
Soylak, Mustafa | Agirbas, Metin | Yilmaz, Erkan
A novel and green method was developed for enrichment of maneb (manganese ethylene-bisdithiocarbamate) with a supramolecular solvent liquid phase microextraction method. The microextraction method has been used for the first time in the literature for separation-preconcentration of maneb. 1-decanol and tetrahydrofuran were used in the supramolecular solvent formation. The Mn²⁺ content of maneb was extracted in the supramolecular solvent phase as 1-(2-pyridylazo)-2-naphthol complex at pH 12.0. Manganese concentration was determined by UV–Vis spectrophotometer at 555 nm. Then, the maneb concentration equivalent to manganese concentration was calculated. The analytical parameters which effective in the method, including pH, volume of reagents, and sample volume were optimized. The limit of detection and the limit of quantification values for maneb were calculated as 2.22 μg L⁻¹ and 7.32 μg L⁻¹, respectively. The method was successfully applied in the analysis of the maneb content of water and food samples.
Показать больше [+] Меньше [-]Fear of the water or something else? Evaluating consumer willingness to pay for food products amid COVID-19 outbreak possibly from a Hubei “Wet Market” Полный текст
2021
Chen, Xuan | Hu, Wuyang | Qing, Ping | Li, Jian
Synthesis of magnetic Cu/CuFe2O4@MIL-88A(Fe) nanocomposite and application to dispersive solid-phase extraction of chlorpyrifos and phosalone in water and food samples Полный текст
2021
Amini, Shima | Amiri, Maryam | Ebrahimzadeh, Homeira | Seidi, Shahram | Hejabri kandeh, Saeed
Herein, a novel Cu/CuFe₂O₄@iron-based metal-organic framework 88 A (Cu/CuFe₂O₄@MIL-88A(Fe)) was developed through a scalable hydrothermal strategy for the magnetic dispersive solid-phase extraction of chlorpyrifos and phosalone from water, fruit juice, and vegetable samples prior to corona discharge ion mobility spectrometry analysis. The resulting nanocomposite was characterized in detail, and thus the investigation indicated that the magnetic nanocomposite had good adsorption capacity, high surface area, dispersion, and superparamagnetic properties. In addition, the fabricated sorbent provided different interactions with the target analytes, (hydrogen bonding, hydrophobic contacts, and π-π stacking interactions) resulting in the improvement of extraction efficiency. The applied method based on Cu/CuFe₂O₄@ MIL-88A(Fe) was validated by investigating the affecting parameters, including the amount of magnetic nanocomposite (10.0 mg), sample pH (7.0), salt content (7.5 % w/v), extraction time (5 min), type of elution (150 μL of methanol), and desorption time (2 min). The linearity of the method was found to be in the range of 0.6–300.0 ng mL⁻¹ and 1.5–500.0 ng mL⁻¹, for chlorpyrifos and phosalone with the coefficient of determination of ≥0.9991. The limits of detections (LODs) of 0.2 and 0.5 ng mL⁻ ¹ were obtained for the determination of chlorpyrifos and phosalone, respectively. The relative standard deviation values (RSDs %) were calculated in the range of 4.4 %–6.1 % (intra-day, n = 5) and 6.3 %–8.0 % (inter-day, n = 3) for three days. Ultimately, the developed method was successfully applied for the extraction of the desired analytes from various spiked samples with acceptable recoveries (88.3–100.4 %).
Показать больше [+] Меньше [-]Combined liquid phase microextraction and fiber-optics-based cuvetteless micro-spectrophotometry for sensitive determination of ammonia in water and food samples by the indophenol reaction Полный текст
2021
Jain, Archana | Soni, Soumitra | Verma, K. K.
The Berthelot reaction for ammonia is revisited with the aim of miniaturization and addressing interferences as encountered with food and water samples. Headspace single drop microextraction of ammonia in phosphoric acid served to attain selectivity in complex matrices, and liquid-liquid microextraction of red or blue indophenol species into 1-octanol-isooctane (60:40, v/v) resulted into high sensitivity. Fiber-optics-based cuvetteless micro-spectrophotometry has been used for colorimetric determination on microliter volumes of extract. The linear dynamic range, limit of detection and enrichment factor have been found to be 0.2–3 mg kg⁻¹, 0.14 mg kg⁻¹ and 38, respectively, measuring red species for milk, cheese and beer (4.9–5.5% error; 4.8–6.3% RSD; n = 5); and 5–400 µg L⁻¹, 0.4 µg L⁻¹ and 137, respectively, measuring blue species for water samples (3.3–5.7% error; 3.6–6.8% RSD; n = 5). A plausible reaction scheme has been proposed for nitroprusside catalysis in indophenol reaction.
Показать больше [+] Меньше [-]Activación de residuos agroalimentarios para su empleo como adsorbentes de nitratos en aguas | Activation of agri-food wastes for use as nitrate adsorbents in water Полный текст
2021
Benavides Pasachoa, Diana Marcela | Moreno Angosto, José Manuel | Fernández López, José Antonio | Ingeniería Química y Ambiental
El objetivo general del presente trabajo es realizar diferentes tratamientos de activación de residuos agroalimentarios para utilizar en la eliminación de nitratos en aguas. Como objetivos más específicos se han fijado los siguientes: Acondicionar la residuos agroalimentarios a emplear Realizar diferentes tratamientos de activación Caracterizar la biomasa antes y después de la activación Estudiar la capacidad de retención de la biomasa modificada Redactar el TFM Resumen de la Oferta: Se pretende valorizar diferentes residuos procedentes de la industria agroalimentaria, para emplear como adsorbentes de nitratos presentes en aguas. Para ello, y con objeto de mejorar el rendimiento de eliminación se procederá a realizar diferentes tratamientos de activación. Posteriormente se caracterizarán las biomasas sin modificar y modificadas, así como se procederá a evaluar su capacidad de retención. | Escuela Técnica Superior de Ingeniería Industrial | Universidad Politécnica de Cartagena
Показать больше [+] Меньше [-]The Use of Winter Water Temperature and Food Composition by the Copepod <i>Cyclops vicinus</i> (Uljanin, 1875) to Provide a Temporal Refuge from Fish Predation Полный текст
2021
Jong-Yun Choi | Seong-Ki Kim
Frequent predation induces various defense strategies in prey, including morphological changes or migration patterns in zooplankton. We hypothesized that the winter dominance of <i>Cyclops vicinus</i> in the Upo Wetlands, South Korea, is an evolved temporal defense mechanism to avoid fish predation. Long-term data (2014–2019) showed that fish consumed the most cyclopoid copepods from spring to autumn. <i>Lepomis macrochirus</i> preferentially consumed <i>C. vicinus</i>; thus, <i>C. vicinus</i> density was lower from spring to autumn. However, <i>C. vicinus</i> was abundant in winter when fish consumed fewer copepods. Nauplii density began to increase in late autumn (October–November), and their population growth was fueled through consumption of <i>Cyclotella</i> sp. and <i>Rhodomonas</i> sp. Culture experiments showed that <i>Cyclotella</i> sp. contributed more to the growth stage (copepodite or subadult) after nauplii than <i>Rhodomonas</i> sp. <i>C. vicinus</i> density was lower in the winters of 2013 and 2016 when the densities of these phytoplankton prey species were lower. In summary, although winter conditions were suitable for copepod survival and population growth, <i>C. vicinus</i> relied heavily on the diversity and species composition of its food sources. The winter dominance of <i>C. vicinus</i> could increase regional biodiversity and contribute significantly to the stability of the freshwater food web.
Показать больше [+] Меньше [-]A semi-qualitative approach to the operationalization of the Food–Environment–Energy–Water (FE2W) Nexus concept for infrastructure planning: A case study of the Niger Basin Полный текст
2021
Seidou, Ousmane | Ringler, Claudia | Kalcic, Spela | Ferrini, Luca | Ramani, Traoré Abdou | Guero, Abdou
The countries sharing the Niger River suffer from poor access to clean water and energy as well as food insecurity. The Niger River Basin Authority is tasked with advancing progress in all these areas while also reducing environmental degradation. To help the basin authority and its investors prioritize portfolio activities that support multiple securities of interest, we developed a mixed-methods approach that engaged basin countries in qualitatively ranking projects to meet energy, environmental and food security goals, complemented by quantitative modelling for the more complex ranking of water and environmental sustainability goals, necessitated by complex upstream–downstream linkages.
Показать больше [+] Меньше [-]Exploring the Use of Switchable Hydrophilicity Solvents as Extraction Phase for the Determination of Food-Packaging Contaminants in Coconut Water Samples by Gas Chromatography-Mass Spectrometry Полный текст
2021
Corazza, Gabriela | Oenning, Anderson Luiz | Bernardi, Gabrieli | Merib, Josias | Carasek, Eduardo
This work proposes, for the first time, a method based on homogenous liquid-liquid microextraction with switchable hydrophilicity solvent as extraction phase (SHS-HLLME) for the determination of food-packaging contaminants including dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), benzyl butyl phthalate (BBP), di-n-octyl phthalate (DNOP), 4-octylphenol (4-OP), 4-nonylphenol (4-NP), and benzophenone (BZP) in coconut water samples by gas chromatography-mass spectrometry (GC-MS). Experimental parameters that can influence extraction efficiency, such as type and volume of SHS, sample volume, NaOH volume, temperature, and extraction time, were investigated. Using the optimal conditions, the calibration curves were linear from 0.5 to 30 μg L⁻¹ for DMP and DEP; 1 to 30 μg L⁻¹ for DBP, BBF, and DNOF; and 5 to 30 μg L⁻¹ for BZP, 4-OP, and 4-NP. The coefficients of determination ranged from 0.9830 to 0.9972. The relative recoveries varied from 82 to 130%, and the intra- and inter-day precision values were lower than 18% for all analytes for the concentrations of 5, 15, and 30 μg L⁻¹. Limit of detection and quantification ranged from 0.15 to 1.51 μg L⁻¹ and from 0.50 to 5.0 μg L⁻¹, respectively. In addition, the robustness of the methodology was examined and exhibited satisfactory results. Finally, the method developed was successfully applied for the analysis of six coconut water samples from food packaging. In this particular case, at least one analyte was found in five samples analyzed in the range of <LOQ to 3.37 μg L⁻¹.
Показать больше [+] Меньше [-]Heavy metals and arsenic phytoremediation potential of invasive alien wetland plants Phragmites karka and Arundo donax: Water-Energy-Food (W-E-F) Nexus linked sustainability implications Полный текст
2021
Rai, Prabhat Kumar
Heavy metals and arsenic (As) are hazardous to the environment and human health. In concert with the problem of metallic contaminants, certain macrophytes in wetlands are harmful invasive alien plants (IAP). Nevertheless, there exists a knowledge gap, that whether all IAP are nuisance or possess certain beneficial role as bioresource in environmental amelioration. Present study conducted microcosm experiments to investigate the heavy metals and As phytoremediation potential of IAP (Phragmites karka (Retz.) Trin. ex Steud. and Arundo donax L.). The results revealed the significant but differential heavy metals remediation (31.0 to 73.3%; p ≤ 0.01) and anti-oxidative defence potential (in terms of enzymatic activity) of IAP. Highest translocation factor (TF-0.89) was noted in case of P. karaka for Zn. Rhizofiltration (TF < 1) was observed as main phytoremediation mechanism. In the present experimental design, P. karka was noted as better phytoremediation tool than A. donax. In future studies, phytoremediation potential of these IAP can be tested at field scale, in conjunction with ‘Water-energy food (W-E-F) nexus’ and ‘biorefinery’ co-benefits.
Показать больше [+] Меньше [-]A semi-qualitative approach to the operationalization of the Food–Environment–Energy–Water (FE2W) Nexus concept for infrastructure planning: A case study of the Niger Basin Полный текст
2021
Seidou, Ousmane; Ringler, Claudia; Kalcic, Spela; Ferrini, Luca; Ramani, Traoré Abdou; Guero, Abdou | http://orcid.org/0000-0002-8266-0488 Ringler, Claudia
The countries sharing the Niger River suffer from poor access to clean water and energy as well as food insecurity. The Niger River Basin Authority is tasked with advancing progress in all these areas while also reducing environmental degradation. To help the basin authority and its investors prioritize portfolio activities that support multiple securities of interest, we developed a mixed-methods approach that engaged basin countries in qualitatively ranking projects to meet energy, environmental and food security goals, complemented by quantitative modelling for the more complex ranking of water and environmental sustainability goals, necessitated by complex upstream–downstream linkages. | PR | IFPRI3; ISI; CRP5; DCA; 1 Fostering Climate-Resilient and Sustainable Food Supply; Capacity Strengthening | EPTD | CGIAR Research Program on Water, Land and Ecosystems (WLE)
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