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1.
J Hazard Mater ; 474: 134793, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38850954

RESUMO

Progress in the development of biodegradable or biobased ionic liquids (ILs) has led to the design of green compounds for several applications. Herein, four biocompatible dicationic ionic liquids (DILs) with ammonium-phosphonium cations and amino acid anions were synthesized and investigated their environmental impact. The structures of the DILs were confirmed by spectral analyses (1H, 13C and 31P NMR). Furthermore, physicochemical properties such as density, viscosity and refractive index were determined. Water content, bromide content and solubility were thereafter determined as the parameters needed for further studies. Subsequently, their antifeedant activity towards economically important pests of grain in storage warehouses: the granary weevil, the confused flour beetle, and the khapra beetle was examined, showing the dependence on structure. Moreover, selected DILs were investigated for toxicity towards white mustard, Daphnia magna, and Artemia franciscana to specify the environmental impact. These studies were complemented by understand the biodegradation of DILs by bacterial communities derived from soil at the agricultural land. The result was DILs with limited environmental footprints that have great potential for further application studies.


Assuntos
Aminoácidos , Artemia , Daphnia , Líquidos Iônicos , Líquidos Iônicos/toxicidade , Líquidos Iônicos/química , Animais , Aminoácidos/química , Aminoácidos/análise , Daphnia/efeitos dos fármacos , Artemia/efeitos dos fármacos , Compostos de Amônio/química , Compostos Organofosforados/química , Cátions , Ânions/química , Meio Ambiente , Biodegradação Ambiental , Besouros/efeitos dos fármacos
2.
Toxicology ; 504: 153793, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38574843

RESUMO

Photodynamic therapy (PDT) utilizes the potential of photosensitizing substances to absorb light energy and produce reactive oxygen species. Tetra-cationic porphyrins, which have organic or coordination compounds attached to their periphery, are heterocyclic derivatives with well-described antimicrobial and antitumoral properties. This is due to their ability to produce reactive oxygen species and their photobiological properties in solution. Consequently, these molecules are promising candidates as new and more effective photosensitizers with biomedical, environmental, and other biomedical applications. Prior to human exposure, it is essential to establish the toxicological profile of these molecules using in vivo models. In this study, we used Caenorhabditis elegans, a small free-living nematode, as a model for assessing toxic effects and predicting toxicity in preclinical research. We evaluated the toxic effects of porphyrins (neutral and tetra-cationic) on nematodes under dark/light conditions. Our findings demonstrate that tetra-methylated porphyrins (3TMeP and 4TMeP) at a concentration of 3.3 µg/mL (1.36 and 0.93 µM) exhibit high toxicity (as evidenced by reduced survival, development, and locomotion) under dark conditions. Moreover, photoactivated tetra-methylated porphyrins induce higher ROS levels compared to neutral (3TPyP and 4TPyP), tetra-palladated (3PdTPyP and 4PdTPyP), and tetra-platinated (3PtTPyP and 4PtTPyP) porphyrins, which may be responsible for the observed toxic effects.


Assuntos
Caenorhabditis elegans , Luz , Fármacos Fotossensibilizantes , Porfirinas , Animais , Caenorhabditis elegans/efeitos dos fármacos , Porfirinas/toxicidade , Porfirinas/química , Fármacos Fotossensibilizantes/toxicidade , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Espécies Reativas de Oxigênio/metabolismo , Fotoquimioterapia/métodos , Cátions/toxicidade , Relação Dose-Resposta a Droga
3.
J Environ Manage ; 356: 120559, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38471324

RESUMO

In November 2015, a catastrophic rupture of the Fundão dam in Mariana (Brazil), resulted in extensive socio-economic and environmental repercussions that persist to this day. In response, several reforestation programs were initiated to remediate the impacted regions. However, accurately assessing soil health in these areas is a complex endeavor. This study employs machine learning techniques to predict soil quality indicators that effectively differentiate between the stages of recovery in these areas. For this, a comprehensive set of soil parameters, encompassing 3 biological, 16 chemical, and 3 physical parameters, were evaluated for samples exposed to mining tailings and those unaffected, totaling 81 and 6 samples, respectively, which were evaluated over 2 years. The most robust model was the decision tree with a restriction of fewer levels to simplify the tree structure. In this model, Cation Exchange Capacity (CEC), Microbial Biomass Carbon (MBC), Base Saturation (BS), and Effective Cation Exchange Capacity (eCEC) emerged as the most pivotal factors influencing model fitting. This model achieved an accuracy score of 92% during training and 93% during testing for determining stages of recovery. The model developed in this study has the potential to revolutionize the monitoring efforts conducted by regulatory agencies in these regions. By reducing the number of parameters that necessitate evaluation, this enhanced efficiency promises to expedite recovery monitoring, simultaneously enhancing cost-effectiveness while upholding the analytical rigor of assessments.


Assuntos
Ecossistema , Compostos de Ferro , Solo/química , Monitoramento Ambiental , Mineração , Brasil , Ferro/análise , Cátions , Rios/química
4.
Colloids Surf B Biointerfaces ; 237: 113839, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38492411

RESUMO

Herein, we have employed a supramolecular assembly of a cationic dye, LDS-698 and a common surfactant sodium dodecyl sulfate (SDS) as a turn-on fluorescent sensor for protamine (Pr) detection. Addition of cationic Pr to the solution of dye-surfactant complex brings negatively charged SDS molecules together through strong electrostatic interaction, assisting aggregation of SDS way before its critical micellar concentration (CMC). These aggregates encapsulate the dye molecules within their hydrophobic region, arresting non-radiative decay channels of the excited dye. Thus, the LDS-698•SDS assembly displays substantial enhancement in fluorescence intensity that follows a nice linear trend with Pr concentration, providing limit of detection (LOD) for Pr as low as 3.84(±0.11) nM in buffer, 124.4(±6.7) nM in 1% human serum and 28.3(±0.5) nM in 100% human urine. Furthermore, high selectivity, low background signal, large stokes shift, and emission in the biologically favorable deep-red region make the studied assembly a promising platform for Pr sensing. As of our knowledge it is the first ever Pr sensory platform, using a very common surfactant (SDS), which is economically affordable and very easily available in the market. This innovative approach can replace the expensive, exotic and specialized chemicals considered for the purpose and thus showcase its potential in practical applications.


Assuntos
Surfactantes Pulmonares , Tensoativos , Humanos , Tensoativos/química , Antídotos , Heparina , Dodecilsulfato de Sódio/química , Cátions/química
5.
Chemosphere ; 352: 141399, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38331263

RESUMO

Layered double hydroxides (LDHs) have been recognized to have great potential for the treatment of heavy metals in wastewater and soil through various mechanisms. Isomorphic substitution is an important mechanism for the sorption of heavy metal cations with LDH reconstruction and highly stable product formation. However, sorption performance, structure-related relationships, and, more importantly, stability are still poorly understood. In this study, a series of LDHs with different structures were synthesized to evaluate their cadmium (Cd) sorption performance and stability concerning the isomorphic substitution mechanism. Divalent cation types in the LDH lattice determined the Cd sorption capacity as well as the isomorphic substitution possibility, following the order of hydroxide solubility of divalent cations (MII): Ca2+>Mg2+>(Cd2+) > Ni2+>Zn2+. In addition, CaAl-LDH exhibited a super-high Cd sorption capacity of 625.0 mg g-1. Cd sorption by LDHs with different interlayer anion types and divalent/trivalent cation molar ratios varied due to crystallite size-related MII release through cation-exchange/isomorphic substitution. Coexisting cations (e.g., Zn2+, Ni2+, Mg2+) influence the sorption performance of MII-LDH mainly through isomorphic substitution mechanism, largely depending on the solubility of MII(OH)2 with a trend of stable product formation. Furthermore, Mg2.9Cd0.1AlCl-LDH was fabricated, and limited Cd dissolution without destruction of the LDH structure was observed under various conditions. For example, only 7.69%, 2.16% and 0.96% of Cd was released from as-prepared Mg2.9Cd0.1AlCl-LDH in NaCl solution (0.02 mol L-1, pH 5), soil extract, and soil matrix, respectively. The very low leaching of Cd from Cd-containing LDHs indicated the high stability of LDH-sorbed Cd via isomorphic substitution and feasible practical application in Cd sequestration in wastewater treatment and soil remediation.


Assuntos
Cádmio , Metais Pesados , Cátions Bivalentes , Cátions , Hidróxidos/química , Solo
6.
J Contam Hydrol ; 260: 104283, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101230

RESUMO

Iron (Fe) contamination in groundwater is a widespread issue, necessitating the implementation of efficient removal methods to ensure the provision of safe drinking water. To contribute to the development of effective and sustainable solutions for addressing Fe contamination problems, this study investigated the potential of natural brown coal (BC) as a cost-effective adsorbent for removing dissolved Fe from groundwater. The study also explored the regeneration and reusability potential, as well as the effects of operational parameters, including pH, temperature, adsorbate concentration, and competitive ions, on the adsorption process. The equilibrium data fitted very well with the Langmuir model (R2 = 0.983), yielding a maximum adsorption capacity of 1.41 mg g-1. The adsorption kinetics were well described by the pseudo-second-order kinetic model. Notably, higher solution pH, Fe concentration, and temperature values led to higher Fe removal. The adsorption process exhibited endothermic behaviour, accompanied by an increase in randomness at the interface between the BC and the Fe. The BC was easily regenerated and maintained good adsorption capacity after four cycles of adsorption and regeneration. However, the presence of high-valent cations could affect its performance. Fourier-transform infrared spectrometry, coupled with structural and aqueous solution elemental analyses, revealed a synergetic adsorption mechanism, comprising ion-exchange with mono and divalent basic cations and complexation with functional groups. Overall, these findings highlight the potential of brown coal as a cost-effective adsorbent for Fe removal from groundwater.


Assuntos
Água Potável , Água Subterrânea , Poluentes Químicos da Água , Ferro/química , Adsorção , Água Subterrânea/química , Cinética , Cátions , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio
7.
Environ Monit Assess ; 195(10): 1257, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37776387

RESUMO

Groundwater is contaminated by anthropogenic factors such as industry, domestic waste, and excessive fertilizers. Groundwater samples, which were obtained from 50 different wells in July 2020, were used in this study. Thirteen hydrochemical properties, including electrical conductivity (EC), pH, total dissolved solids (TDS), total hardness (TH), nitrate NO3-, anions, and cations were analyzed. Also, types of groundwater were investigated via the Piper diagram. The groundwater was also evaluated for irrigation suitability using the sodium percentage (Na%), sodium adsorption ratio (SAR), Kelly's index (KI), residual sodium carbonate (RSC), potential salinity, magnesium hazard (MR), and permeability index (PI). The samples were assessed for drinking the suitability using the water quality index (WQI) and the nitrate pollution index (NPI). Geographic information systems (GIS) were used to create spatial distribution maps of irrigation water quality indices, WQI, and NPI values. The results of major cations varied sodium 28.69-211.80 mg/L, calcium 78.74-258.89 magnesium 27.78-161.30 mg/L, and potasium 0.10-3.57 mg/L. The results from the study area showed that 62.70 of EC, 32.40% of PI, 20.09% of RSC, 51.55% of PS, and 49.36% of MR were inappropriate for irrigation purposes. The NPI data ranged from - 0.75 to 9.65, and 21.06% of the study areas were heavily polluted. The WQI showed that almost 62.90% of the experimental area was categorized as poor, very poor, and inappropriate for drinking water purposes, whereas 37.10% of the areas were categorized as good and excellent.


Assuntos
Água Potável , Água Subterrânea , Poluentes Químicos da Água , Qualidade da Água , Nitratos/análise , Monitoramento Ambiental , Magnésio , Poluentes Químicos da Água/análise , Água Subterrânea/química , Sódio , Cátions
8.
Glob Chang Biol ; 29(24): 7012-7028, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37589204

RESUMO

Terrestrial enhanced weathering (EW) through the application of Mg- or Ca-rich rock dust to soil is a negative emission technology with the potential to address impacts of climate change. The effectiveness of EW was tested over 4 years by spreading ground basalt (50 t ha-1 year-1 ) on maize/soybean and miscanthus cropping systems in the Midwest US. The major elements of the carbon budget were quantified through measurements of eddy covariance, soil carbon flux, and biomass. The movement of Mg and Ca to deep soil, released by weathering, balanced by a corresponding alkalinity flux, was used to measure the drawdown of CO2 , where the release of cations from basalt was measured as the ratio of rare earth elements to base cations in the applied rock dust and in the surface soil. Basalt application stimulated peak biomass and net primary production in both cropping systems and caused a small but significant stimulation of soil respiration. Net ecosystem carbon balance (NECB) was strongly negative for maize/soybean (-199 to -453 g C m-2 year-1 ) indicating this system was losing carbon to the atmosphere. Average EW (102 g C m-2 year-1 ) offset carbon loss in the maize/soybean by 23%-42%. NECB of miscanthus was positive (63-129 g C m-2 year-1 ), indicating carbon gain in the system, and EW greatly increased inorganic carbon storage by an additional 234 g C m-2 year-1 . Our analysis indicates a co-deployment of a perennial biofuel crop (miscanthus) with EW leads to major wins-increased harvested yields of 29%-42% with additional carbon dioxide removal (CDR) of 8.6 t CO2 ha-1 year-1 . EW applied to maize/soybean drives a CDR of 3.7 t CO2 ha-1 year-1 , which partially offsets well-established carbon losses from soil from this crop rotation. EW applied in the US Midwest creates measurable improvements to the carbon budgets perennial bioenergy crops and conventional row crops.


Assuntos
Dióxido de Carbono , Ecossistema , Solo , Poaceae , Zea mays , Poeira , Cátions , Agricultura
9.
Environ Monit Assess ; 195(9): 1044, 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37589779

RESUMO

Ash collected from thrown-away by-products while preparing a popular traditional food additive, kolakhar of the Assamese community of North East, India, was used as an alternate cost-effective, porous bioadsorbent option from the conventional activated carbon for the purification of carcinogenic dyes laden water. The base material for kolakhar preparation was taken from the discarded banana stem waste to stimulate agricultural waste management. Methylene blue (MB) and basic fuchsin (BF) dyes were used as model cationic dyes. Characterization techniques like CHN, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission-scanning electron microscope (FE-SEM), energy dispersive X-ray (EDX), and Brunauer-Emmett-Teller (BET) analysis of the prepared banana stem ash (BSA) reveal the presence of high inorganic contents and functional groups in the irregular, porous bioadsorbent with surface area 55.534 m2 g-1. Various regulating parameters studied to optimize the adsorption capacity of BSA were bioadsorbent dose (0.1-3 g/L), temperature (298-318 K), contact time (0-150 min), pH (2-9), and initial dye concentrations (10-40 mg/L). Non-linear kinetic models suggested Elovich for both MB and BF adsorption, while the non-linear isotherm model suggested Langmuir and Temkin for MB and BF adsorption, respectively, as best-fitted curves. The monolayer adsorption capacity (qm) for MB and BF was 15.22 mg/g and 24.08 mg/g at 318 K, respectively, with more than 95% removal efficiency for both dyes. The thermodynamic parameters studied indicated that the adsorption is spontaneous. The ∆H0 values of MB and BF adsorptions were 2.303 kJ/mol (endothermic) and - 29.238 kJ/mol (exothermic), respectively.


Assuntos
Corantes , Monitoramento Ambiental , Corantes de Rosanilina , Adsorção , Agricultura , Cátions , Azul de Metileno
10.
J Agric Food Chem ; 71(32): 12346-12356, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37539957

RESUMO

The flavor and taste of Lonicerae japonicae flos (LJF) products are heavily influenced by geographical origin. Tracing the geographical origin is an important aspect of LJF quality assessment. Here, DNA methylation analysis coupled with chemometrics revealed that, in 10 CpG islands upstream of genes in the chlorogenic acid and iridoid biosynthetic pathways, DNA methylation differences appear close association with LJF geographical origin. DNA methylation status in these CpG islands was determined using the cationic conjugated polymer fluorescence resonance energy transfer method. As a result, LJFs from 39 geographical origins were classified into four groups corresponding to Northern China, Central Plain of China, Southeast China, and Western China, according to cluster analysis and principal component analysis. Our findings contribute to an understanding of the modulation of LJF taste and can assist in understanding how DNA methylation in LJF varies with geographical origin.


Assuntos
Metilação de DNA , Transferência Ressonante de Energia de Fluorescência , Cátions/química , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem , Metabolômica , Epigênese Genética , China
11.
Environ Monit Assess ; 195(6): 687, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37195479

RESUMO

Groundwater is a valuable resource for developmental activities, and its demand is growing as surface water becoming scarce. Groundwater demand is increasing, resulting in reduction in water level and deterioration in water quality. A total of 156 groundwater samples were taken from Gaya, a district in Bihar (India), to check the safety of drinking water. The quality of groundwater was assessed using a water quality index (WQI). Analysed samples were assessed using a variety of physicochemical characteristics, and statistical methods principal component analysis (PCA) and cluster analysis (CA) were used as they are effective and efficient. As per the Gibbs, plot majority of the sample falls in the rock-water interaction and some evaporation dominance field. The domination of major cation in the order of Ca2+ > Mg2+ > Na+ and the major anions followed the order of HCO3- > [Formula: see text]>[Formula: see text]>[Formula: see text]>[Formula: see text]. The KMO's sample adequacy value of 0.703 and the significance level of Bartlett's test of sphericity (0.0001) were indicating that PCA may be implemented. Using the PCA, the three components recovered explained 69.58% of the total variation. Cluster analysis classified the groundwater sample into three cluster based on the similarities among chemical parameters involved in groundwater quality. HCA exhibit less, intermediate, and heavily mineralized groundwater characteristics of groups I, II, and III, respectively. The major parameters affecting the water quality in the study region are TDS, Ca2+, Mg2+, HCO3-, [Formula: see text]. WQI indicates 17% of the sample were found to be of very poor quality and not consumable. The study's findings offer insights and understanding into groundwater pollution regimes. These results used for water quality assessment leading to improved environmental management and planning and in decision-making for water quality management.


Assuntos
Água Potável , Água Subterrânea , Poluentes Químicos da Água , Qualidade da Água , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Água Subterrânea/análise , Cátions/análise , Índia , Água Potável/análise
12.
J Sci Food Agric ; 103(9): 4676-4684, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36905092

RESUMO

BACKGROUND: Caffeic acid (CA) has anti-oxidation and anti-inflammatory. However, the poor hydrophilicity of CA limits its biological activities. In this work, hydrophilic glyceryl monocaffeate (GMC) was synthesized by esterification using different caffeoyl donors (deep eutectic solvent and solid CA). Cation-exchange resins were used as the catalysts. The effects of reaction conditions were also investigated. RESULTS: The mass transfer limitation of esterification was eliminated using deep eutectic solvent. Compared with the previous catalysts (immobilized lipase Novozym 435), an economic cation-exchange resin, Amberlyst-35 (A-35), showed good catalytic performance for GMC preparation. The activation energies of GMC synthesis and CA conversion were 43.71 kJ mol-1 and 43.07 kJ mol-1 , respectively. The optimal reaction conditions were a temperature reaction of 90 °C, catalyst load of 7%, glycerol/CA molar ratio of 5:1 (mol mol-1 ), and reaction time of 24 h, which resulted in a maximum GMC yield and CA conversion of 69.75 ± 1.03% and 82.23 ± 2.02%, respectively. CONCLUSION: The results of the work showed a promising alternative for the synthesis of GMC. © 2023 Society of Chemical Industry.


Assuntos
Resinas de Troca de Cátion , Solventes Eutéticos Profundos , Solventes , Lipase/metabolismo , Esterificação , Interações Hidrofóbicas e Hidrofílicas , Enzimas Imobilizadas/metabolismo , Cátions
13.
Langmuir ; 39(7): 2509-2519, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36748988

RESUMO

With recent advances and anticipated proliferation of lipid nanoparticle (LNP)-delivered vaccines and therapeutics, there is a need for the availability of internationally recognized reference materials of LNP systems. Accordingly, we developed six LNP and liposome (anionic, neutral, and cationic each) candidate reference material formulations and thoroughly characterized by dynamic light scattering their particle hydrodynamic size (Z-avr) and polydispersity. We also evaluated the particle size homogeneity and long-term -70 °C and 4 °C storage stability using multiple large sets of randomly selected vials for each formulation. The formulations stored at -70 °C remained stable and homogeneous for a minimum of 9 months. The Z-avr relative combined uncertainty and the long-term variability were both <1.3% for liposome formulations and anionic LNPs, (3.9% and 1.7%) for neutral LNPs, and (6.7% and 4.4%) for cationic LNPs. An inadvertent few-hour-long storage temperature increase to -35 °C due to a freezer malfunction resulted in a small change of the size and size distribution of anionic liposomes and LNPs but, unexpectedly, a larger size increase of the neutral and cationic liposomes (≤5%) and LNPs (≤25%). The mean Z-avr values of the LNPs stored at 4 °C appeared to slowly increase with t1/3, where t is the storage time, and the Z-avr between-vial heterogeneity and mean polydispersity index values appeared to decrease; no change was observed for liposomes. The size and size distribution evolution of LNPs stored at 4 °C was attributed to an incomplete equilibration of the formulations following the addition of sucrose prior to the initial freezing. Such a process of size increase and size distribution narrowing has not been previously discussed nor observed in the context of LNPs.


Assuntos
Lipossomos , Nanopartículas , Congelamento , Tamanho da Partícula , Cátions , RNA Interferente Pequeno
14.
Water Environ Res ; 95(3): e10845, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36789617

RESUMO

Freshwater lenses are groundwater sources of limited dimensions that can be usually found in a variety of climates worldwide. These aquifers' quality is important for socioeconomic development, being cation exchange one of the most important geochemical processes that can change the water geochemistry. This study aims to assess the cation exchange processes that determine the chemistry of freshwater lenses in a multilayer aquifer type, considering the center-east of the Pampean Region (Argentina) as a case study. Water samples were taken from the freshwater lenses at different depths to analyze major ions in the laboratory. In addition, geological profiles were made along with the extraction of sediment samples for X-ray diffractometry (XRD) and laboratory tests to analyze the cation exchange capacity. The results show that water stored in the lenses has a vertical facies variation from Ca-HCO3 to Na-HCO3 . According to the laboratory results, the change of water facies mainly occurs in the clayey sediments that divide the carbonate bioclastic material above and the loessic sediment below, being cation exchange the most important process. PRACTITIONER POINTS: Cation exchange is the main geochemical process regulating groundwater chemistry. Hydrochemical changes determine the quality of freshwater lenses. Na/Ca exchange is mainly regulated by the groundwater flow into the bioturbated clay. Batch exchange tests were also carried out to quantify the Na/Ca exchange processes.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Humanos , Água , Monitoramento Ambiental/métodos , Fácies , Poluentes Químicos da Água/análise , Água Doce , Cátions , Sódio , Qualidade da Água
15.
Environ Sci Pollut Res Int ; 30(4): 10643-10663, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36085221

RESUMO

Sustainable management of groundwater resources in geological transition zones (GTZ) is essential due to their complex geology, increasing population, industrialization, and climate change. Groundwater quality monitoring and assessment represent a viable panacea to this problem. Therefore, there is a great need to investigate groundwater resources in terms of their chemistry and pollution to ascertain their quality and implement robust pollution abatement strategies. This study focused on the characterization of groundwater in a typical geological transition zone in northeastern Nigeria. Eighty-seven (87) groundwater samples were collected from dug wells and boreholes during the 2017 dry season. pH, conductivity, and total dissolved solids (TDS) were measured in situ using a multiparameter probe, while major cations and anions were measured using atomic absorption spectrometry and ion chromatography, respectively. Data were analyzed using descriptive statistics, principal component analysis (PCA), water quality index, and standard hydrochemical plots. TDS ranged between 95 and 1154 mg L-1 in basement terrains and between 49 and 1105 in sedimentary areas. pH ranged between 6.8 and 7.7 mg L-1 in basement terrains and between 5.0 and 6.5 in sedimentary areas, suggesting a moderately acidic to alkaline low mineralized groundwater. Calcium (2.6-128.0 mg L-1) was the dominant cation in the basement areas, suggesting silicate weathering/dissolution, while sodium (1.9-106.0 mg L-1) dominated the sedimentary zones due to base exchange reactions. The PCA analysis suggests that mineral dissolution (mostly silicate weathering) controls the hydrochemistry of the basement aquifers, while ion exchange and albite weathering, with some influence of anthropogenic factor, control the sedimentary aquifers. The water quality index revealed that the basement setting was predominated by poor to unsuitable groundwater, while the sedimentary terrain was characterized by potable groundwater. The dominant hydrochemical facie in the basement areas was Ca2+-(Mg2+)-HCO3- characteristic of recharge meteoric water. The Na+- (K+)-HCO3- facie characterized the sedimentary zones, indicative of cation exchange reactions, while the mixed water facie typifies the geological contact zones. The shallow nature of the basement groundwaters makes them more susceptible to geogenic and anthropogenic pollution compared to the sandstone aquifers. However, the basement aquifers have better irrigation indices (Kelly ratio and soluble sodium percent) as compared to the sandstone aquifers, which exhibit poor Kelly ratios (< 1) and soluble sodium percent (> 50) ratings. Results from the study clearly highlight the poor-unsuitable groundwater quality in parts of the studied GTZ and can be very instrumental to the policymakers in implementing sustainable water treatment strategies and cleaner production technologies in GTZ to forestall the incidence of water-related diseases.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Humanos , Monitoramento Ambiental/métodos , Geologia , Nigéria , Fácies , Poluentes Químicos da Água/análise , Água Subterrânea/química , Qualidade da Água , Cátions/análise
16.
Environ Monit Assess ; 194(12): 862, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36214927

RESUMO

Ismailia Canal is one of the significant streams of the Nile River in Egypt. The study aimed to determine the water quality of Ismailia Canal based on the regional and seasonal variability of physicochemical parameters, irrigation criteria, and the irrigation water quality index (IWQI). It was observed that the physicochemical parameters were within the acceptable FAO irrigation limits. All cations and anions values were within the acceptable FAO limits for irrigation, except the potassium (K+) concentrations were over the permissible irrigation limits. The one-way analysis of variance (ANOVA) suggested a significant seasonal variation in the canal's water quality concerning all parameters (p value ˂ 0.05). However, the regional variation among various sites was statistically insignificant (p value > 0.05). Statistical analysis was used to calculate the correlation coefficient between different parameters, and the study showed highly significant correlation coefficients between different pairs of water quality parameters. The correlation matrix showed that the pH significantly affected IWQI (r = 0.661). The irrigation criterion values for Ismailia Canal were good, and the WQI levels for irrigation utilization at all studied sites were satisfactory. Deterioration of water quality may occur due to industrial, municipal, and agricultural activities. Drainage water should be treated before being mixed with irrigation water to improve its suitability for irrigation.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Irrigação Agrícola , Ânions/análise , Cátions/análise , Monitoramento Ambiental , Água Subterrânea/análise , Potássio/análise , Poluentes Químicos da Água/análise , Qualidade da Água
17.
Environ Monit Assess ; 195(1): 29, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36282453

RESUMO

The aim of the study was to determine the groundwater characteristics of rural and industrial zones in the Kannur region. In 2011, 25 groundwater data were collected from the centre for water resource development management (CWRDM), and in 2019, 25 groundwater samples from rural and near-industrial areas were collected and analysed for major anions (HCO3-, CO32-, Cl-, NO3- and SO42-), and cations (TH, Ca2+, Mg2+, Na+, K+ and Fe2+) using APHA standards. To better understand the link between water quality parameters, multivariate statistical analysis approaches such as principal component analysis (PCA), hierarchical cluster analysis (HCA), correlation matrix analysis (CMA), and Pearson correlation bivariate one-tailed analysis (PCBOTA) were used to analyse the inter-relationship of data. The Inverse Distance Weighed (IDW) method was used to generate the spatial distribution of the groundwater quality index (GWQI). In 2011, the water quality index (WQI) value of groundwater samples was excellent at 24.42% and good at 54.14%, which were used for drinking purposes and moderate at 17.22% and poor at 4.22% for irrigation purposes in this study area. In 2019, excellent 21.62%, good 51.56% were used for drinking purpose, and moderate at 18.14%, and poor at 8.68% for irrigation purposes. By comparing the data with BIS and WHO standards, it is clear that groundwater in Kannur district is of good quality. In groundwater samples, the PCA eigen values were reported in 2011 (84.7%) and 2019 (73.4%) for statistical approaches. This study uses HCA and PCBOTA to analyse the elements, resulting in a better understanding of groundwater quality development. GIS based WQI maps were obtained and utilised to gain a better knowledge of the study area's past and present water quality status. We observed that the quality of groundwater in the study region's north-western portion is insufficient for drinking water.


Assuntos
Água Potável , Água Subterrânea , Poluentes Químicos da Água , Sistemas de Informação Geográfica , Água Potável/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Água Subterrânea/análise , Qualidade da Água , Ânions/análise , Cátions/análise , Índia
18.
Int J Mol Sci ; 23(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36077173

RESUMO

A new synthesis method is described for the first time to produce silver nanoclusters (AgNCs) by using the tyrosine (Tyr) amino acid. Several important parameters (e.g., molar ratios, initial pH, reaction time etc.) were optimized to reach the highest yield. The formed Tyr-AgNCs show characteristic blue emission at λem = 410 nm, and two dominant fluorescence lifetime components were deconvoluted (τ1 ~ 3.7 and τ2 ~ 4.9 ns). The NCs contained metallic cores stabilized by dityrosine. For possible application, the interactions with several metal ions from the tap water and wastewater were investigated. Among the studied cations, four different ions (Cu2+, Ni2+, Fe3+, and Rh3+) had a dominant effect on the fluorescence of NCs. Based on the detected quenching processes, the limit of detection of the metal ions was determined. Static quenching (formation of a non-luminescent complex) was observed in all cases by temperature-dependent measurements. The calculated thermodynamic parameters showed that the interactions are spontaneous ranked in the following order of strength: Cu2+ > Fe3+ > Rh3+ > Ni2+. Based on the sign and relations of the standard enthalpy (ΔH°) and entropy changes (ΔS°), the dominant forces were also identified.


Assuntos
Nanopartículas Metálicas , Cátions , Cobre/química , Fluorescência , Íons , Nanopartículas Metálicas/química , Prata/química , Espectrometria de Fluorescência/métodos , Tirosina
19.
Sci Rep ; 12(1): 11698, 2022 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-35810170

RESUMO

In this study,the water samples were collected from 31 sites of Tawang, Arunachal Pradesh, India (North-Eastern Himalaya), during the winter season to check the suitability of water for drinking and irrigation purposes.The study scientifically demonstrates the estimation of Water quality index (WQI) andhydrogeochemical characteristics of surface water samples by utilizing multivariate statistical methods. The main water quality parameters considered for this study were TDS, conductivity, salinity, pH, hardness, cations and anions. WQI was calculated in order to find out the deviation in the water quality parameters particularly with respect to BIS permissible limits.The major influencing factors responsible for the variation in these parameters were derived by using Principal component analysis (PCA) and Correlation matrix.To check the suitability of water for drinking purpose, hydrogeochemical facies and rock water interaction was derived by using well established methods such as Piper Plot (determine water type), WQI (Quality monitoring), and saturation index (for mineral dissolution). The results revealed that the silicate weathering was the main ionic source in comparison to carbonate weathering which is due to the higher dissolution capacity of silicate minerals.The results of the scattered plot between (Ca2+ + Mg2+)-(HCO3- + SO42-) versus (Na+ + K+)-Cl- (meq/L) highlighted thation exchange occurs between Mg2+ and Ca2+ofsurface water with Na+ and K+of rock /soil. This means that calcium ion was getting adsorbed, and sodium ion was getting released. The Ca2+-Mg2+-HCO3-, Na+-HCO3-and Na+-Cl- type of surface water suggested permanent and temporary hardness respectively in the studied region. The dominant cations of this study were Na+ and Ca2+ while the dominant anions were HCO3- and SO42-. In order to check the suitability of water sources for irrigation, parameters like, Magnesium hazard (MH), Total hardness (TH), Permeability Index (PI), Kelly Index (KI), Sodium adsorption rate (SAR), Sodium percentage (Na%), and Residual sodium carbonate (RSC) were determined. The results showed that 93% of the samples had PI score < 75, which indicates the suitability of the water for irrigation. Also the WQI calculation showed an average WQI value of 82.49, amongst which 61% samples were in the range of 0-50 being considered as good for drinking, while 39% were catageorised as unsuitable for drinking showing a value of > 50. Hence the above findings reveal that geogenic activities play a major role in influencing the water quality of Tawang region. Hence suitable water treatment technologies or methods might be used to eliminate thenon desirable elements and minerals present in surface water.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Cátions/análise , Monitoramento Ambiental/métodos , Água Subterrânea/análise , Índia , Minerais/análise , Sódio/análise , Poluentes Químicos da Água/análise , Qualidade da Água
20.
J Hazard Mater ; 439: 129588, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-35850070

RESUMO

In this study, seven different materials were analyzed and includes coffee grounds (CG), two types of cellulose (CGC and CC), two types of modified cellulose (CT and CTCD), and cross-linked ß-cyclodextrin (CD-1 and CD-2) were tested as adsorbents for the removal of dyes from the wastewater. The composition, morphology, and presence of functional groups in the obtained sorption materials were characterized by elemental analysis, SEM, TG/DTA, and FTIR spectroscopy. The sorption processes of the model contaminant, crystal violet (CV), were studied by kinetics and equilibrium models. The results showed, that using CTCD, the dye was adsorbed rapidly in 1 min and the slowest adsorption occurred in 20 min by CG. The time evolution was adjusted using a two-model, pseudo second-order model (CG and CGC) and pseudo first-order model in the rest adsorbents. According to the Langmuir and Sips isotherm models, the maximum adsorption capacities were very high in each case ranging from 1092.24 to 1220.40 mg g-1. Moreover, the adsorption capacity of the near-natural materials remained even higher after five regeneration cycles. The regeneration is almost waste-free and the materials used can be decomposed during composting. In addition, almost complete removal of cationic dyes was observed during the treatment of real wastewater samples.


Assuntos
Poluentes Químicos da Água , beta-Ciclodextrinas , Adsorção , Cátions , Celulose/química , Café , Corantes/química , Concentração de Íons de Hidrogênio , Cinética , Desenvolvimento Sustentável , Águas Residuárias/química , Poluentes Químicos da Água/química
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