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Urbanization and industrialization are responsible for environmental contamination in the air, water, and soil. These activities also generate large amounts of heavy metal ions in the environment, and these contaminants cause vari...
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Urbanization and industrialization are responsible for environmental contamination in the air, water, and soil. These activities also generate large amounts of heavy metal ions in the environment, and these contaminants cause various types of health issues in humans and other animals. Hexavalent chromium, lead, and cadmium are toxic heavy metal ions that come into the environment through several industrial processes, such as tanning, electroplating, coal mining, agricultural activities, the steel industry, and chrome plating. Several physical and chemical methods are generally used for the heavy metal decontamination of wastewater. These methods have some disadvantages, including the generation of secondary toxic sludge and high operational costs. Hence, there is a need to develop a cost-effective and eco-friendly method for the removal of heavy metal ions from polluted areas. Biological methods are generally considered eco-friendly and cost-effective. This review focuses on heavy metal contamination, its toxicity, and eco-friendly approaches for the removal of heavy metals from contaminated sites.
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Soil quality in urban areas in India is degraded due to multiple anthropogenic activities.
The objectives of thiswork are to determine the concentration variations, toxicity,
and sources of carbons,metals, and ions in the surfac...
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Soil quality in urban areas in India is degraded due to multiple anthropogenic activities.
The objectives of thiswork are to determine the concentration variations, toxicity,
and sources of carbons,metals, and ions in the surface soil of Raipur, the industrialized
capital city of Chhattisgarh state, India. High concentrations of Al, K, Ca, Ti, Fe, and elemental
carbon (EC) were registered. Relatively lower concentrations of V, Cr, Mn, Ni,
Cu, Zn, Sr, Ba, Pb, organic carbon (OC), and carbonate carbon (CC), as well as ions (viz.
F~–, Cl~–, NO_3~–, SO_4~(2–), Na~+, K~+, Mg~(2+), andCa~(2+)), were also recorded. EC was found to be
one of the major pollutants, although enrichment factors pointed to high contamination
with SO_4~(2–), K+, Mg~(2+)
, Cr,Mn, and Pb; and extreme contamination with NO_3~– and
Ca~(2+). The spatial and temporal variations, enrichment factors, toxicity, and sources of
the chemical species detected in the soil are discussed.
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Water is increasingly being applied for irrigation in vegetable cultivation in the peri-urban zones of rapidly rising cities. Wastewater being used by Farmers is heavily polluted with poisonous heavy metals as a result of industri...
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Water is increasingly being applied for irrigation in vegetable cultivation in the peri-urban zones of rapidly rising cities. Wastewater being used by Farmers is heavily polluted with poisonous heavy metals as a result of industrial discharge and other human activities. As a result, long-term wastewater application is detrimental to soil and vegetable health. The current study looked at the heavy metal concentration (As, Cd, Cr, Hg, and Pb) in agricultural soil, water, and vegetable samples. Heavy metals are the high-density content and not easily accumulated in the soil and water, these metals are dissolved in soil through anthropogenic processes, like humans are using the metals like mercury in lab and after the use they dispose these metal on the soil surface. When these metals are put on the soil surface they decompose and leach into the soil subsurface layer after that they percolate into groundwater.
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Titanium-50 (~(50)Ti) is an important and often requested ion beam for nuclear physics’ experiments. While natural titanium of very high purity is available in different forms; enriched material can only be bought as the dioxide ...
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Titanium-50 (~(50)Ti) is an important and often requested ion beam for nuclear physics’ experiments. While natural titanium of very high purity is available in different forms; enriched material can only be bought as the dioxide or the tetrachloride. These compounds cannot be processed from currently available ion sources with a sufficient beam quality and sufficient beam intensity for a long time. We describe here the process of converting titanium dioxide into the metal, the material analysis of the starting material as well as of the reduced material. Despite varying contamination levels of silicon, chlorine, and tin in the primary materials, we obtained high yields of metallic titanium with different contamination levels. The obtained metallic ~(50)Ti was applied at the accelerator UNILAC for the production of a high intensity ion beam for several month of beam time.
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The Chinese mitten crab (Eriocheir Sinensis) is a popular aquatic product in China. However, these crabs accumulate heavy metals from the ecosystem. The occurrence, source, and risk assessment of heavy metals in crabs from the mai...
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The Chinese mitten crab (Eriocheir Sinensis) is a popular aquatic product in China. However, these crabs accumulate heavy metals from the ecosystem. The occurrence, source, and risk assessment of heavy metals in crabs from the main production area in China were investigated. The abundance of the metals in crabs was Mn >> As > Se > Ni > Cr > Cd > Pb> Hg. Each metal was present at a level less than the national standard (A standard for the limits of contaminants in food from China). Agricultural activities, industrial discharges, and urban sewage were the three main sources of heavy metals accumulation in Chinese mitten crab. Based on an assessment of the target hazard quotient (THQ), arsenic is the most harmful heavy metal in the crabs. In addition, mercury and lead also pose risks. The results indicate that the estimated daily intake (EDI) of mitten crabs in China would not pose a high dietary risk. (THQ < 1). The brown crab meat of females has a higher dietary risk than comparable tissues in males.
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A Novel exploding wire type ion source device is proposed as a metallic ion source of intense pulsed heavy ion beam (PHIB) accelerator. In the device, multiple shot operations are realized without breaking the vacuum. The basic ch...
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A Novel exploding wire type ion source device is proposed as a metallic ion source of intense pulsed heavy ion beam (PHIB) accelerator. In the device, multiple shot operations are realized without breaking the vacuum. The basic characteristics of the device are evaluated experimentally with an aluminum wire of diameter 0.2 mm and length 25 mm. A capacitor bank of capacitance 3 |xF and a charging voltage of 30 kV was used, and the wire was successfully exploded by a discharge current of 15 kA with a rise time of 5.3 (is. Plasma flux of ion current density around 70 A/cm2 was obtained at 150 mm downstream from the device. Thedrift velocity of ions evaluated by atime-of-flight method was 2.7 × 10~4 m/s, which corresponds to the kinetic energy of 100 eV for aluminum ions. From the measurement of the ion current density distribution, the ion flow is found to be concentrated toward the direction where the ion acceleration gap is placed. From the experiment, the device is found to be acceptable for applying the PHIB accelerator.
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A Zn-based 3D MOF,[Zn2(H3L1)(L2)].H2O named PUC-5 was synthesized using trimesic acid(H3I4)and l-(3-aminopropyl)Imidazole(L2)by solvothermal method.PUC-5 has been characterized using SCXRD,PXRD,FT-IR,SEM,XPS,TGA,BET and Zeta poten...
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A Zn-based 3D MOF,[Zn2(H3L1)(L2)].H2O named PUC-5 was synthesized using trimesic acid(H3I4)and l-(3-aminopropyl)Imidazole(L2)by solvothermal method.PUC-5 has been characterized using SCXRD,PXRD,FT-IR,SEM,XPS,TGA,BET and Zeta potential techniques.The PUC-5 exhibited extremely high water and pH stability.We explored the utility of PUC-5 as a sensitive probe for the detection and removal of multiple heavy metal ions(Fe~(2+),Pb~(2+)and V~(5+))from water.The detection limits calculated in the case of Fe~(2+),Pb~(2+)and V~(5+)were 0.129 μM,0.113 μM and 0.246 μM which were found to be lower than the limits established by the world health organisation(WHO)for drinking water.The detection ability of PUC-5 towards targeted metal ions was further confirmed by Zeta potential,FTIR and XPS techniques.Moreover,the adsorption potential of PUC-5 towards Fe~(2+),Pb~(2+)and V~(5+)was studied by the ICP-MS method.Different kinetic and isotherm models were used to assess the effects of time,temperature,adsorbent content and initial metal ions concentration on PUC-5's ability to adsorb Fe~(2+),Pb~(2+),and V~(5+).The adsorption process of metal ions could be well depicted by Pseudo-second-order kinetics and Langmuir isotherm models suggesting monolayer chemisorption with maximum adsorption capacities of 208.7,192.6 and 203.6 mg g~(-1)for Fe~(2+),Pb~(2+)and V~(5+)respectively.Furthermore,the thermodynamic parameters support the spontaneous behaviour and exothermic nature of the adsorption process.Interestingly,PUC-5 is a recyclable material and can be reused with high adsorption efficiency suggesting a high potential of adsorbent towards Fe~(2+),Pb~(2+)and V~(5+).
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Abstract Sensitive and selective detection of the lead ion (Pb2+) plays an important role in terms of both human health and environmental protection, as the heavy metal is fairly ubiquitous and highly toxic. The highly stable fluo...
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Abstract Sensitive and selective detection of the lead ion (Pb2+) plays an important role in terms of both human health and environmental protection, as the heavy metal is fairly ubiquitous and highly toxic. The highly stable fluorescence biosensor is composed of Fe3O4@TiO2 core–shell nanocomposites, functionalized with a carboxyl fluorescein labeled DNA. The morphology, physical and chemical properties of the sensing nanomaterials were studied by transmission electron microscopy, FT-IR spectroscopy (FT-IR), x-ray powder diffraction and vibrating sample magnetometer. UV–visible and fluorescence spectroscopy were used to characterize the fluorescein functionalized magnetic nanoparticles. The performance of Pb2+ detection displayed an excellent linearity (R 2?=?0.995) in the range of 10?10 to 5?×?10?9 ppm with a detection limit of 10?10 ppm, based on the optimization of the fabrication process and aptamers’ specification. The fluorescence biosensor has an accurate response, excellent recoveries and high adsorbent capacities. It was successfully applied for the determination of Pb2+ in contaminated water and serum samples; the detection of limit in both media were 10?10 ppm. These features ensure the potential use of aptamer functionalized magnetic nanocomposites as a new class of non-toxic biocompatible sensors for biological and environmental applications.
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Comprehensive electric-surface, adsorption, X-ray investigations of interaction between ions of heavy 3-d metals with the hydroxylapatite surface have been carried out within a broad range of the pH and concentration of electrolyt...
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Comprehensive electric-surface, adsorption, X-ray investigations of interaction between ions of heavy 3-d metals with the hydroxylapatite surface have been carried out within a broad range of the pH and concentration of electrolytes. At low concentrations of ions of heavy metals the values of their sorption are less than the amount of Ca~2 exchange cations outgoing to the solution. At higher concentrations of ions of heavy metals one can observe a reverse phenomenon: the amount of ions being sorbed exceeds the amount of outcoming Ca~2 ions. The paper provides an explanation for the phenomena being observed. It is shown that the interaction of the zinc chloride solution at low values of the pH with hydroxylapatite a new mineral-scholzite-is formed.
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Sixty-four surface soil samples taken in the vicinity of Al Ain landfill were analysed for cadmium, chromium, copper, nickel, lead and zinc by inductively coupled plasma spectroscopy. Extraction techniques were used to establish t...
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Sixty-four surface soil samples taken in the vicinity of Al Ain landfill were analysed for cadmium, chromium, copper, nickel, lead and zinc by inductively coupled plasma spectroscopy. Extraction techniques were used to establish the association of the total concentrations of the six metals in the soil samples with their contents in the exchangeable, carbonate, iron/manganese oxides, and residual fractions. In the investigated soils the recorded concentrations were as follows: 0.043 mg kg~-1 for cadmium, 19.1 mg kg~-1 for chromium, 53.3 mg kg~-1 for copper, 60 mg kg~-1 for nickel, 13.7 mg kg~-1 for lead, and 117 mg kg~-1 for zinc. Cadmium, chromium, nickel, lead and zinc concentrations in the investigated soil samples reflect the natural background values in shale, whereas copper is slightly enriched. I-geo (geoaccumulation index) values of the metals in the soils under study indicate that they are uncontaminated with cadmium, chromium, nickel, lead and zinc, but contaminated to moderately contaminated with copper. Heavy metal contents in the sediments were found to be significantly influenced by different physicochemical parameters. The effect of these parameters can be arranged in the following order: clay fraction＞ carbonate fraction＞ silt fraction＞ organic matter fractions. A sequential extraction procedure showed that the total concentrations of the heavy metals are largely bound to the residual phase (retained 71.4% of cadmium, 77.8% of chromium, 75% of copper, 47% of nickel, 62.8% of lead, and 75.8% of zinc). A likely sequence of mobility in the investigated soils is as follows: chromium＞ lead＞ nickel＞ cadmium＞ zinc＞ copper.
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