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1.
Nanomaterials (Basel) ; 14(10)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38786773

RESUMO

Climate neutrality for the year 2050 is the goal assumed at the level of the EU27+UK. As Romania is no exception, it has assumed the gradual mitigation of pollution generated by the energy sector, and by 2030, according to 'Fit for 55', the share of energy from renewable sources must reach 42.5% from total energy consumption. For the rest of the energy produced from traditional sources, natural gas and/or coal, modern technologies will be used to retain the gaseous noxes. Even if they are not greenhouse gases, NO and SO2, generated from fossil fuel combustion, cause negative effects on the environment and biodiversity. The adsorption capacity of different materials, three nanomaterials developed in-house and three commercial adsorbents, both for NO and SO2, was tackled through gas chromatography, elemental analysis, and Fourier-transform infrared spectroscopy. Fe-BTC has proven to be an excellent material for separation efficiency and adsorption capacity under studied conditions, and is shown to be versatile both in the case of NO (80.00 cm3/g) and SO2 (63.07 cm3/g). All the developed nanomaterials generated superior results in comparison to the commercial adsorbents. The increase in pressure enhanced the performance of the absorption process, while temperature showed an opposite influence, by blocking the active centers on the surface.

2.
Int J Mol Sci ; 24(19)2023 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-37834434

RESUMO

In the face of escalating environmental challenges, understanding the intricate relationship between plant metabolites, pollution stress, and climatic conditions is of paramount importance. This study aimed to conduct a comprehensive analysis of metabolic variations generated through 1H and 13C NMR measurements in evergreen needles collected from different regions with varying pollution levels. Multivariate analyses were employed to identify specific metabolites responsive to pollution stress and climatic factors. Air pollution indicators were assessed through ANOVA and Pearson correlation analyses. Our results revealed significant metabolic changes attributed to geographical origin, establishing these conifer species as potential indicators for both air pollution and climatic conditions. High levels of air pollution correlated with increased glucose and decreased levels of formic acid and choline. Principal component analysis (PCA) unveiled a clear species separation, largely influenced by succinic acid and threonine. Discriminant analysis (DA) confirmed these findings, highlighting the positive correlation of glucose with pollution grade. Beyond pollution assessment, these metabolic variations could have ecological implications, impacting interactions and ecological functions. Our study underscores the dynamic interplay between conifer metabolism, environmental stressors, and ecological systems. These findings not only advance environmental monitoring practices but also pave the way for holistic research encompassing ecological and physiological dimensions, shedding light on the multifaceted roles of metabolites in conifer responses to environmental challenges.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Traqueófitas , Poluição do Ar/análise , Monitoramento Ambiental/métodos , Análise Multivariada , Glucose/análise , Poluentes Atmosféricos/análise
3.
Nanomaterials (Basel) ; 13(19)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37836278

RESUMO

Until reaching climate neutrality by attaining the EU 2050 level, the current levels of CO2 must be mitigated through the research and development of resilient technologies. This research explored potential approaches to lower CO2 emissions resulting from combustion fossil fuels in power plant furnaces. Different nanomaterials (MOFs versus silica nanoparticles) were used in this context to compare their effectiveness to mitigate GHG emissions. Porous materials known as metal-organic frameworks (MOFs) are frequently employed in sustainable CO2 management for selective adsorption and separation. Understanding the underlying mechanism is difficult due to their textural characteristics, the presence of functional groups and the variation in technological parameters (temperature and pressure) during CO2-selective adsorption. A silica-based nanomaterial was also employed in comparison. To systematically map CO2 adsorption as a function of the textural and compositional features of the nanomaterials and the process parameters set to a column-reactor system (CRS), 160 data points were collected for the current investigation. Different scenarios, as a function of P (bar) or as a function of T (K), were designed based on assumptions, 1 and 5 vs. 1-10 (bar) and 313.15 and 373.15 vs. 313.15-423.15 (K), where the regression analyses through Pearson coefficients of 0.92-0.95, coefficients of determination of 0.87-0.90 and p-values < 0.05, on predictive and on-site laboratory data, confirmed the performances of the CRS.

4.
Sci Total Environ ; 899: 165344, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37414185

RESUMO

Compound specific isotope analysis was extensively used to characterise the environmental processes associated with the abiotic and biotic transformation of persistent halogenated organic pollutants including those of contaminants of emerging concern (CECs). In the last years, the compound specific isotope analysis was applied as tool to evaluate the environmental fate and was expanded to larger molecules like brominated flame retardants and polychlorinated biphenyls. Multi-element (C, H, Cl, Br) CSIA methods have been also employed both in laboratory and field experiments. Nevertheless, despite the instrumental advances of isotope ratio mass spectrometers systems, the instrumental detection limit for gas chromatography-combustion-isotope ratio mass spectrometer (GC-C-IRMS) systems is challenging, especially when it is utilized to δ13C analysis. Liquid chromatography-combustion isotope ratio mass spectrometry methods are challenging, taking into consideration the chromatographic resolution required when analysing complex mixtures. For chiral contaminants, enantioselective stable isotope analysis (ESIA) has turned up as alternative approach but, up to now, it has been used for a limited number of compounds. Taking into consideration the occurrence of new emerging halogenated organic contaminants, new GC and LC methods for non-target screening using high resolution mass spectrometry are needed to be developed prior to the compound specific isotope analysis (CSIA) methods.

5.
Foods ; 12(7)2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37048347

RESUMO

The climate warming trend challenges the chemical risk associated with wine production worldwide. The present study investigated the possible difference between chemical wine profile during the drought year 2012 compared to the post-drought year 2013. Toxic metals (Cd and Pb), microelements (Mn, Ni, Zn, Al, Ba, and Cu), macroelements (Na, Mg, K, Ca, and P), isotopic ratios (87Sr/86Sr and 206Pb/207Pb), stable isotopes (δ18O, δ13C, (D/H)I, and (D/H)II), and climatic data were analyzed. The multivariate technique, correlation analysis, factor analysis, partial least squares-discriminant analysis, and hierarchical cluster analysis were used for data interpretation. The maximum temperature had a maximum difference when comparing data year apart. Indeed, extreme droughts were noted in only the spring and early summer of 2012 and in 2013, which increased the mean value of ground frost days. The microelements, macroelements, and Pb presented extreme effects in 2012, emphasizing more variability in terms of the type of wine. Extremely high Cd values were found in the wine samples analyzed, at up to 10.1 µg/L. The relationship between precipitation and δ18O from wine was complex, indicating grape formation under the systematic influence of the current year precipitation, and differences between years were noted. δ13C had disentangled values, with no differentiation between years, and when coupled with the deuterium-hydrogen ratio, it could sustain the hypothesis of possible adulteration. In the current analysis, the 87Sr/86Sr showed higher values than in other Romanian studies. The temperature had a strong positive correlation with Pb, while the ground frost day frequency correlated with both Pb and Cd toxic elements in the wine. Other significant relationships were disclosed between the chemical properties of wine and climate data. The multivariate statistical analysis indicated that heat stress had significant importance in the chemical profile of the wine, and the ground frost exceeded the influence of water stress, especially in Transylvania.

6.
Foods ; 11(18)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36140966

RESUMO

The 1H-NMR carbohydrates profiling was used to discriminate fruits from Rosaceae family in terms of botanical origin and harvest year. The classification was possible by application of multivariate data analysis, such as principal component analysis (PCA), linear discriminant analysis (LDA) and Pearson analysis. Prior, a heat map was created based on 1H-NMR signals which offered an overview of the content of individual carbohydrates in plum, apricot, cherry and sour cherry, highlighting the similarities. Although, the PCA results were almost satisfactory, based only on carbohydrates signals, the LDA reached 94.39% and 100% classification of fruits according to their botanical origin and growing season, respectively. Additionally, a potential association with the relevant climatic data was explored by applying the Pearson analysis. These findings are intended to create an efficient NMR-based solution capable of differentiating fruit juices based on their basic sugar profile.

7.
Nutrients ; 14(12)2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35745094

RESUMO

Natural ecosystems are polluted with various contaminants, and among these heavy metals raise concerns due to their side effects on both environment and human health. An investigation was conducted on essential oil samples, comparing similar products between seven producers, and the results indicated a wide variation of metal content. The recommended limits imposed by European Union regulations for medicinal plants are exceeded only in Mentha × pipperita (Adams, 0.61 mg/kg). Except for Thymus vulgaris, the multivariate analysis showed a strong correlation between toxic and microelements (p < 0.001). We verified plant species−specific bioaccumulation patterns with non-metric multidimensional scaling analysis. The model showed that Adams, Doterra, Hypericum, and Steaua Divina essential oils originated from plants containing high micro and macroelement (Cu, Mn, Mg, Na) levels. We noted that the cancer risk values for Ni were the highest (2.02 × 10−9−7.89 × 10−7). Based on the target hazard quotient, three groups of elements were associated with a possible risk to human health, including As, Hg, and Cd in the first group, Cr, Mn, Ni, and Co in the second, and Zn and Al in the third. Additionally, the challenge of coupling inter-element relationships through a network plot analysis shows a considerable probability of associating toxic metals with micronutrients, which can address cumulative risks for human consumers.


Assuntos
Mercúrio , Metais Pesados , Óleos Voláteis , Ecossistema , Monitoramento Ambiental/métodos , Humanos , Mercúrio/análise , Medição de Risco
8.
Plants (Basel) ; 10(12)2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34961181

RESUMO

Three species of Stachys genus (S. byzantina, S. officinalis, S. sylvatica) were investigated in the present study in terms of aromatic profile and total polyphenol content, as well as antibacterial activity and antioxidant capacity. Gas chromatography coupled with flame ionization detection (GC/FID) was used for exploration of the herbal alcoholic extracts. Using statistical analysis, volatile organic compounds (VOCs) and total phenolic chemical fingerprints were compared in order to describe differences and identify putative signature traits of the three Stachys species. The results showed that the analyzed Stachys extracts have a total polyphenol content being between 197 ± 0.27 mg GAE/g for S. sylvatica and 232 ± 43 mg GAE/g for S. officinalis. The antioxidant activity was between 444 ± 58 mM Trolox/g (S. sylvatica) and 602 ± 75 mM Trolox/g (S. officinalis). The volatile compounds identified were mostly sesquiterpenes, followed by monoterpenes and secondary compounds. The most abundant in all three species was germacrene D (21.9% 28-25.2%). The multivariate analysis demonstrated the potential of using plant tissue VOC profiles to discriminate between different Stachy species, with a total of 31 VOCs being identified from all three species. Although there were strong similarities among the three species' VOC profiles, distinctions can be made using chemometric analysis. The microbiological results showed an antimicrobial capacity of all three extracts, especially on Gram-positive bacteria. In addition to increasing consumers' understanding regarding the health benefits of these Stachy species, this investigation contributes to defining and preserving a precious genetic and cultural-historical biodiversity.

9.
Plants (Basel) ; 10(12)2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34961215

RESUMO

In this work, the challenges and progression in stable isotope investigation, from the analytical tools and technical sample preparation procedures to the dendroclimatological experiments, were reviewed in terms of their use to assess tree physiological responses to environmental changes. Since the isotope signature of whole wood is not always a reliable tool in studying the climate changes, cellulose is often preferred as the study material in paleoclimatic studies. Nevertheless, the isotope analysis of cellulose is challenging due to the difficulty to remove the other wood components (extractives, lignin, pectin, and hemicelluloses). Additionally, in the case of hydrogen isotope analysis, about 30% of the hydrogen atoms of cellulose are exchanged with the surrounding water, which complicates the isotope analysis. In recent years, more automated isotope analysis methods were developed based on high temperature pyrolysis of cellulose, followed by the chromatographic separation of H2 from CO and by their individual isotope analysis using isotope ratio mass spectrometry. When used to investigate climate factors, the combined isotope analysis δ13C and δ18O appears to be the most promising isotope tool. In contrast, the role of δ2H values is yet to be elucidated, together with the development of new methods for hydrogen isotope analysis.

10.
Molecules ; 24(24)2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31818015

RESUMO

This study aims to assess the capability of the 1H-NMR profiling of fruits from different genera in combination with multivariate data analysis to provide feasible information for fruit juices' authenticity in terms of botanical origin. Nine fruit varieties from four genera were selected for the experimental plan. The juice obtained from the fruits was characterized using the 1H-NMR technique, selecting the obtained amino acid profile of fruits as a potential specific fingerprint. Due to the complex information provided by the NMR spectra, a chemometric approach of the data was further applied to enable the differentiation of the fruit samples, highlighting thus its suitability as a discrimination tool for the varietal origin. The advantage of this analytical approach is given by the relatively simple working procedure, which consists of an easy, fast, and accessible preparation stage while providing complex information on fruit composition.


Assuntos
Aminoácidos/química , Sucos de Frutas e Vegetais , Frutas/química , Bebidas , Humanos , Espectroscopia de Ressonância Magnética , Análise Multivariada
11.
Molecules ; 24(7)2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30965673

RESUMO

:The aim of the study was to investigate the differences between walnut genotypes of various geographical and genetic origins grown under the same or different environmental conditions. The biological material analyzed consisted in walnut kernels of 34 cultivars, nine advanced selections, and six hybrids harvested in 2015 and 2016, summing up to a total of 64 samples. The walnuts, walnut oil, and residue were characterized in respect to their chemical (proximate composition-fat, protein, nutritional value, fatty acids profile by ¹H-NMR) and carbon-13 isotopic composition. The data was used to statistically discriminate the cultivars according to composition, geographical area of origin, and year of harvest, comparing the Romanian cultivars, selections, and hybrids with the internationally available ones.


Assuntos
Ácidos Graxos/análise , Juglans/genética , Nozes/química , Proteínas de Plantas/análise , Isótopos de Carbono , China , Genótipo , Grécia , Juglans/química , Juglans/classificação , Juglans/metabolismo , Valor Nutritivo , Filogeografia , Espectroscopia de Prótons por Ressonância Magnética , Romênia
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