scholarly journals Proton Competition and Free Ion Activities Drive Cadmium, Copper, and Nickel Accumulation in River Biofilms in a Nordic Ecosystem

Environments ◽  
2020 ◽  
Vol 7 (12) ◽  
pp. 112
Author(s):  
Vincent Laderriere ◽  
Louise-Emmanuelle Paris ◽  
Claude Fortin
Keyword(s):  
Surface Water ◽  
Metal Ion ◽  
Metal Content ◽  
Metal Accumulation ◽  
Anthropogenic Activities ◽  
Ion Concentration ◽  
Dissolved Metals ◽  
Biomonitoring Tool ◽  
Water Ph ◽  
Decreasing Ph

Biofilms can be used as a biomonitoring tool to determine metal bioavailability in streams affected by mining and other anthropogenic activities. Surface water and biofilm were sampled over two years from rivers located in the vicinity of a mine located in a Nordic ecosystem (Nunavik, Quebec). Biofilm metal content (Cd, Cu, and Ni) as well as a variety of physicochemical properties were determined to examine relationships between metal accumulation and water quality. Among the three metals of interest, copper and nickel had the highest levels of accumulation and cadmium had the lowest. When considering the exposure levels, nickel was the most abundant metal in our sampling sites. Both exposure and accumulation levels were consistent over time. Biofilm metal content was highly correlated to the ambient free metal ion concentration for sites of circumneutral pHs for all three metals. When the surface water pH was below 6, biofilm metal content was much lower than at other sites with similar aqueous metal concentrations of exposure. This apparent protective effect of decreasing pH can be explained by proton competition with dissolved metals for uptake binding sites at the surface of the organisms within the biofilm as described by the Biotic Ligand Model principles. The relationships obtained for Cd and Cu were overlapping those observed in previous publications, indicating strong similarities in metal accumulation processes in biofilms over very large geographical areas. Although more data are needed for Ni, our results show that biofilms represent a promising metal biomonitoring tool.

Investigation on the quality of water from Jabi Lake in Abuja, Nigeria

2020 ◽  
Vol 45 (5) ◽  
Author(s):  
Emeka Chima Ogoko ◽  
Ajayi Olayinka Sylvester
Keyword(s):  
Surface Water ◽  
Trace Metal ◽  
Water Samples ◽  
Physicochemical Parameters ◽  
Metal Ion ◽  
Pollution Index ◽  
Ion Concentration ◽  
Iron Cobalt ◽  
Quality Of Water ◽  
Who Standards

Surface water may constitute public health issues if the water is contaminated. Consequent upon this assertion, the physicochemical parameters and tr ace metal concentration of Jabi Lake surface water were analysed and compared with WHO standards. Sixteen water samples were taken for analysis from Jabi Lake within Abuja in Nigeria. Official Methods of Analysis of the Association of Official Analytical Chemists (AOAC) were adopted in the analysis of the physicochemical parameters while heavy metals ions determination was performed using Atomic Absorption Spectrophotometer. The results obtained revealed marked differences in the levels of some physicochemical properties and trace metal ion concentration in the surface water samples when compared with WHO standards. Though most physicochemical parameters were within acceptable and safe limits, but with nitrate having higher concentrations. The concentrations of manganese, iron, cobalt, lead and chromium were well above the WHO maximum permissible limits for surface water. The pollution index of manganese, iron, cobalt, lead and chromium were above unity (1.0), indicating very high level of pollution. The results of the physicochemical and trace metal analysis when compared with WHO suggest that the water samples from Jabi Lake was not suitable for drinking while the concentrations of the metal ions were found decreasing in this order; Pb ˃Fe˃Cr˃Mn˃Co˃Zn.

Utilization of Fe-Oxide Composites for as Removal from Aqueous Solutions

2017 ◽  
Vol 262 ◽  
pp. 630-633
Author(s):  
Alexandra Bekényiová ◽  
Zuzana Danková ◽  
Iveta Štyriaková ◽  
Darina Štyriaková
Keyword(s):  
Metal Ion ◽  
Ion Concentration ◽  
Maximum Adsorption Capacity ◽  
Arsenic Adsorption ◽  
Fe Oxide ◽  
Two Samples ◽  
Oxide Ratio ◽  
Decreasing Ph ◽  
Oxide Composites ◽  
Oxide Sample

This work was done to assess the arsenate (AsV ) removal from the model solution by sorbents based on Fe-oxide. Two samples were compared in sorption properties, synthetically prepared Fe-oxide and bentonite/iron oxide (ratio 2:1). The effect of pH and initial metal ion concentration was investigated. The optimum pH for arsenic adsorption by both samples was found to be about 3.0. The adsorption increased very significantly with decreasing pH for both samples. The Fe-oxide sample achieved the maximum adsorption capacity 24,1 mg.g-1 AsV at pH 3, composite sample 14,1 mg.g -1 AsV at pH 3. The adsorption of AsV on Fe-oxide sample increased with the increasing initial metal ion concentration up to 40 mg/l and then equilibrium was established, by contrast of bentonite/Fe-oxide sample shown no significant change at this concentration range.

scholarly journals A Comparative Accuracy of Regularized and Tension Spline Methods to Estimate and Model the Surface Water pH of Pulau Tuba, Langkawi, Kedah

2021 ◽  
Vol 15 (2) ◽  
pp. 116-134
Author(s):  
Sharir Aizat Kamaruddin ◽  
◽  
Nor Atikah Husna Ahmad Nasir ◽  
Nur Syafiqah Rahim ◽  
Norlin Shuhaime ◽  
...  
Keyword(s):  
Surface Water ◽  
Spline Interpolation ◽  
Anthropogenic Activities ◽  
Pearson Correlation ◽  
Coefficient Of Determination ◽  
Spline Method ◽  
Positioning Systems ◽  
Water Ph ◽  
The Impact ◽  
Tension Spline

This research is conducted to assess the accuracy of spline interpolation methods to predict and model the surface water pH of Pulau Tuba, Langkawi, Kedah, Malaysia. In-situ sampling activities using pH-meter and Geographic Positioning Systems (GPS) were carried out during high tides and at noon in November 2018. The development of spatial models was constructed using Regularized and Tension spline methods. Then, validation of models was carried out to compare the observed and predicted values of pH using correlation analysis, regression analysis, and error analysis. The accuracy of the developed map was calculated using the overall accuracy equation. This research found that the regularized spline method had more accuracy in estimating surface water pH variability than the tension spline method. Pearson correlation coefficient (r), Coefficient of determination (R2), Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) were reported at 0.896, 0.803, 0.0265 and 0.0344 for the regularized spline method,respectively. The developed spatial model was then transformed into a map by adding map elements such as legend, title, north arrow, and scales for effective visualization. The developed map has an accuracy of 87.50%. The surface water pH was found at the range of 7-8. Low reading of pH is expected due to the addition of rainwater to the coastal water of Pulau Tuba, Langkawi, Kedah. The research outcomes would benefit government and non-government agencies to monitor the coastal and ocean acidification and the development of strategic policies and rules to reduce the impact of anthropogenic activities and climate changes for this area.

QUANTITATIVE MEASUREMENT OF METAL ION CONCENTRATION OF PROTEINS SEPARATED BY ELECTROPHORESIS

1996 ◽  
Vol 06 (01n02) ◽  
pp. 215-225 ◽  
Author(s):  
G. WEBER ◽  
D. STRIVAY ◽  
C. MENENDEZ ◽  
B. SCHOEFS ◽  
M. BERTRAND
Keyword(s):  
Content Analysis ◽  
Quantitative Determination ◽  
Gel Electrophoresis ◽  
Metal Ion ◽  
Metal Content ◽  
Quantitative Measurement ◽  
Polyacrylamide Gel Electrophoresis ◽  
Ion Concentration ◽  
X Ray

This communication is devoted to nature determination and quantification by PIXE of metals contained in proteins after their separation by PolyAcrylamide Gel Electrophoresis (PAGE). After the electrophoresis, the gel is dried and each track is scanned with a 2.5 MeV proton beam which triggers metal X-ray fluorescence and then, allows to determine the type of metals contained in an electrophoretic band. For quantitative determination of the amount of the metal contained inside the band, the characteristic X-ray peak area is compared with those obtained with polyacrylamide gels doped with the same metal. The normalization has been achieved by using RBS measurements on the gel itself. The procedure presented seems to be a very useful multielementary method for the metal content analysis and for the determination of the metal amounts inside proteins after their separation by electrophoresis. Furthermore it allows to check if metals remain bound to proteins.

scholarly journals On the Road to Sustainable Water Supply: Reducing Public Health Risks and Preserving Surface Water Resources in the Milluni Micro-Basin, Bolivia

Environments ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 4
Author(s):  
Paola Andrea Alvizuri Tintaya ◽  
Esteban Manuel Villena Martínez ◽  
Bárbara Micó Vicent ◽  
Jaime Lora Garcia ◽  
Juan Ignacio Torregrosa-López ◽  
...  
Keyword(s):  
Public Health ◽  
Surface Water ◽  
Water Resources ◽  
Metal Ion ◽  
Heavy Metal Contamination ◽  
Anthropogenic Activities ◽  
Monitoring Program ◽  
Surface Water Resources ◽  
Sustainable Water Supply

Bolivia is among the countries with the highest availability of freshwater globally. However, many of its natural sources are impacted by anthropogenic activities, such as mining. Water is intimately linked to public health and is essential to achieving sustainable development. It is necessary to preserve water resources by designing and validating monitoring programs that help control the quality of the sources that supply important population centers. The study area in this research is the upper part of the Milluni micro-basin, whose lagoon system supplies water for two large cities. Milluni is close to illegal and abandoned mining areas, making the region highly vulnerable to heavy metal contamination. This study aimed to optimize the resources available for monitoring Milluni. The frequency of monitoring was statistically determined, and the correlation between parameters measured in situ (pH and conductivity) and metal ion concentrations to determine low-cost indicators to monitor the presence of heavy metals. A multivariate analysis of friction of the results of the pilot year of the monitoring program designed for Milluni, considering the characteristics and economic limitations, is presented. An approximation of the quality of the surface water resources of Milluni is presented as a result of the monitoring operations.

Hydro-geochemical properties with respect to landuse in the southernmost river of Kerala

2018 ◽  
Vol 6 (1) ◽  
Author(s):  
Badusha M. ◽  
Santhosh S
Keyword(s):  
Organic Carbon ◽  
Drainage Basin ◽  
Anthropogenic Activities ◽  
Oxygen Demand ◽  
Ion Concentration ◽  
Total Hardness ◽  
Hydrogen Ion Concentration ◽  
Geochemical Properties ◽  
Quality Of Water

The hydro geochemical features of Neyyar River for a period of one year from May 2015 to April 2016 were analyzed. Six sampling sites were fixed considering physiography and present landuse pattern of the river basin. The residents in the drainage basin are primarily responsible for framing a better landuse and thereby maintain a good water and sediment regime. Geospatial pattern of the present landuse of the study area indicated that the sustainability of this river ecosystem is in danger due to unscientific landuse practices, which is reflected in the river quality as well. The parameters such as hydrogen ion concentration, electrical conductivity, chloride, Biological Oxygen Demand, total hardness and sulphate of river water and Organic Carbon of river bed sediments were analyzed in this study. The overall analysis shows that the highland areas are characterized by better quality of water together with low organic carbon, which is mainly due to better landuse and minimal reclamation. The midland and lowland areas are characterized by poor quality of water with high organic carbon, which is due to high anthropogenic activities and maximum pollutants associated with the region together with the alteration in landuse from a traditional eco-friendly pattern to a severely polluted current pattern.

Use of agro-waste (Musa paradisiaca peels) as a sustainable biosorbent for toxic metal ions removal from contaminated water

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Contact Time ◽  
Metal Ion ◽  
Equilibrium Concentration ◽  
Ion Concentration ◽  
Contaminated Water ◽  
Musa Paradisiaca ◽  
Percentage Removal ◽  
Adsorbent Dose

A study of removal of heavy metal ions from heavy metal contaminated water using agro-waste was carried out with Musa paradisiaca peels as test adsorbent. The study was carried by adding known quantities of lead (II) ions and cadmium (II) ions each and respectively into specific volume of water and adding specific dose of the test adsorbent into the heavy metal ion solution, and the mixture was agitated for a specific period of time and then the concentration of the metal ion remaining in the solution was determined with Perkin Elmer Atomic absorption spectrophotometer model 2380. The effect of contact time, initial adsorbate concentration, adsorbent dose, pH and temperature were considered. From the effect of contact time results equilibrium concentration was established at 60minutes. The percentage removal of these metal ions studied, were all above 90%. Adsorption and percentage removal of Pb2+ and Cd2+ from their aqueous solutions were affected by change in initial metal ion concentration, adsorbent dose pH and temperature. Adsorption isotherm studies confirmed the adsorption of the metal ions on the test adsorbent with good mathematical fits into Langmuir and Freundlich adsorption isotherms. Regression correlation (R2) values of the isotherm plots are all positive (>0.9), which suggests too, that the adsorption fitted into the isotherms considered.

Surface Water Quality Assessment from a Mining Area. Case study, Groapa Burlacu lake, Targu Ocna, Romania

2019 ◽  
Vol 70 (10) ◽  
pp. 3678-3680
Author(s):  
Alina Cochiorca ◽  
Narcis Barsan ◽  
Florin Marian Nedeff ◽  
Ion Sandu ◽  
Emilian Florin Mosnegutu ◽  
...  
Keyword(s):  
Water Quality ◽  
Surface Water ◽  
Surface Water Quality ◽  
Water Quality Assessment ◽  
Mining Area ◽  
Physical Parameters ◽  
Mining Activities ◽  
Quality Of Water ◽  
Nacl Concentration ◽  
Water Ph

This paper presents a study on assessment of water quality. According to a study, mining activities have a significant impact on water quality (lakes, surface water and groundwater), which has become a major problem globally. Due to mining and exploitation processes, lakes can be formed around these mines. Also, these lakes have been formed around the world and are steadily increasing. The purpose of this study is to watch the quality of water from the area around mining activities. This study refers to the, Groapa Burlacu lake around the mining exploitation Targu Ocna, Romania. This lake was formed on the northern bottle of the massive salt, strongly affected by the underground activities. Sampling for the determination the concentrations of Cl- and NaCl from the studied area was made at different depths (0 m, -5 m, -10 m, -15 m, -20 m, -25 m, -30 m, -35 m -40 m). Besides these concentrations, physical parameters of the water (pH, turbidity, electrical conductivity, dissolved oxygen and temperature) were also measured. To determine the physical parameters in the monitored area, sampling was done from four different points of the area and then put together for analysis. These parameters were measured on site using portable equipment. The data on the analyzed concentrations indicate that at depths of less than 5.0 m, the NaCl concentration values are more than 250 g/L.

scholarly journals Clinically Applicable Cyclotron-Produced Gallium-68 Gives High-Yield Radiolabeling of DOTA-Based Tracers

Biomolecules ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1118
Author(s):  
Emma Jussing ◽  
Stefan Milton ◽  
Erik Samén ◽  
Mohammad Mahdi Moein ◽  
Lovisa Bylund ◽  
...  
Keyword(s):  
Metal Ion ◽  
Metal Content ◽  
Gamma Spectroscopy ◽  
Radiochemical Yield ◽  
High Yield ◽  
Automated Synthesis ◽  
Molar Activity ◽  
Icp Ms ◽  
Gallium 68 ◽  
Fe Impurities

By using solid targets in medical cyclotrons, it is possible to produce large amounts of 68GaCl3. Purification of Ga3+ from metal ion impurities is a critical step, as these metals compete with Ga3+ in the complexation with different chelators, which negatively affects the radiolabeling yields. In this work, we significantly lowered the level of iron (Fe) impurities by adding ascorbate in the purification, and the resulting 68GaCl3could be utilized for high-yield radiolabeling of clinically relevant DOTA-based tracers. 68GaCl3 was cyclotron-produced and purified with ascorbate added in the wash solutions through the UTEVA resins. The 68Ga eluate was analyzed for radionuclidic purity (RNP) by gamma spectroscopy, metal content by ICP-MS, and by titrations with the chelators DOTA, NOTA, and HBED. The 68GaCl3eluate was utilized for GMP-radiolabeling of the DOTA-based tracers DOTATOC and FAPI-46 using an automated synthesis module. DOTA chelator titrations gave an apparent molar activity (AMA) of 491 ± 204 GBq/µmol. GMP-compliant syntheses yielded up to 7 GBq/batch [68Ga]Ga-DOTATOC and [68Ga]Ga-FAPI-46 (radiochemical yield, RCY ~ 60%, corresponding to ten times higher compared to generator-based productions). Full quality control (QC) of 68Ga-labelled tracers showed radiochemically pure and stable products at least four hours from end-of-synthesis.

scholarly journals Chemical Composition and Corrosion Behavior of a-C:H/DLC Film-Coated Titanium Substrate in Simulated PEMFC Environment

Coatings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 820
Author(s):  
Beibei Han ◽  
Mengyuan Yan ◽  
Dongying Ju ◽  
Maorong Chai ◽  
Susumu Sato
Keyword(s):  
Corrosion Resistance ◽  
Corrosion Behavior ◽  
Metal Ion ◽  
Ion Beam ◽  
Titanium Substrate ◽  
Corrosion Current ◽  
Ion Concentration ◽  
Bipolar Plates ◽  
High Adhesion ◽  
Corrosion Behaviors

The amorphous hydrogenated (a-C:H) film-coated titanium, using different CH4/H2 and deposition times, was prepared by the ion beam deposition (IBD) method, which has the advantage of high adhesion because of the graded interface mixes at the atomic level. The chemical characterizations and corrosion behaviors of a-C:H film were investigated and evaluated by SEM, AFM, Raman spectroscopy, EPMA, TEM and XPS. An a-C:H film-coated titanium was corroded at 0.8 V, 90 °C in a 0.5 mol/L H2SO4 solution for 168 h. The metal ion concentration in the H2SO4 corrosion solution and the potentiodynamic polarization behavior were evaluated. Results indicate that a higher CH4/H2 of 1:0 and a deposition time of 12 h can result in a minimum ID/IG ratio of 0.827, Ra of 5.76 nm, metal ion concentration of 0.34 ppm in the corrosion solution and a corrosion current of 0.23 µA/cm2. The current density in this work meets the DOE’s 2020 target of 1 µA/cm2. Electrical conductivity is inversely proportional to the corrosion resistance. The significant improvement in the corrosion resistance of the a-C:H film was mainly attributed to the increased sp3 element and nanocrystalline TiC phase in the penetration layer. As a result, the a-C:H film-coated titanium at CH4/H2 = 1:0 with improved anti-corrosion behavior creates a great potential for PEMFC bipolar plates.

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