Ppm Pb2 Research Articles

HO-1 and Nrf-2 deficiency affects generation and differentiation of induced pluripotent stem cells

The sensing element of biosensor is prepared by the immobilization of urease onto nano-structured polyaniline (PANi)-Nafion® (NSPN)/Au/Al2O3 synthesized by the chronopotentiometric technique. The sensitivity of lead ion at an amperometric urease based biosensor is obtained to be 743.5 µA ppm−1 for the linear dynamic range of 0.1–1.0 ppm Pb2+. The irreversible inhibiting kinetic models of the mercury and lead ions at the amperometric biosensors are proposed. The values of Kd (dissociation equilibrium constant of adsorbed type of enzyme and heavy metal ion) and kirr (irreversible inhibition reaction rate constant) for mercury and lead ions are obtained to be 0.45 ppm, 1.66 × 10−3 s−1, 8.67 ppm and 3.16 × 10−3 s−1, respectively. Compared with lead ion detection, the higher sensitivity to mercury ion of the biosensor is mainly caused by a higher inhibition efficiency (kirr/Kd).

Kinetics of urease inhibition-based amperometric biosensors for mercury and lead ions detection

The sensing element of biosensor is prepared by the immobilization of urease onto nano-structured polyaniline (PANi)-Nafion® (NSPN)/Au/Al2O3 synthesized by the chronopotentiometric technique. The sensitivity of lead ion at an amperometric urease based biosensor is obtained to be 743.5µA ppm−1 for the linear dynamic range of 0.1–1.0ppm Pb2+. The irreversible inhibiting kinetic models of the mercury and lead ions at the amperometric biosensors are proposed. The values of Kd (dissociation equilibrium constant of adsorbed type of enzyme and heavy metal ion) and kirr (irreversible inhibition reaction rate constant) for mercury and lead ions are obtained to be 0.45ppm, 1.66×10−3 s−1, 8.67ppm and 3.16×10−3 s−1, respectively. Compared with lead ion detection, the higher sensitivity to mercury ion of the biosensor is mainly caused by a higher inhibition efficiency (kirr/Kd).

The Effects of Oil Palm Empty Fruit Bunch Sorbent Sizes on Plumbum (II) Ion Sorption

Oil Palm Empty Fruit Bunch (OPEFB) contributes more than 50% of oil palm biomass wastes in Malaysia. This provides tremendous opportunities for value-added product generation from recycling and utilizing its latent capacity. In this work, the performance of physically-pretreated OPEFB fibers without any chemical treatment for Pb2+ removal from aqueous system was evaluated. Three different size ranges (1-5 cm, 0.5-2 mm and 0.005-0.02 mm) of raw sorbent, pH (4-10) and contact time (2-150 min) for Pb2+ batch adsorption were tested. The kinetic data were evaluated by the pseudo-first-order, pseudo-second-order and intra-particle diffusion model. The experimental data were well described by the pseudo-second-order model with r2=0.997. Adsorption efficiency was size-dependent with about 38% sorption increase at 0.005-0.02 mm, and reached 94% efficiency, achieved 47.49 mg/g capacity with 500 ppm Pb2+ at pH 7.5, in 60 min. The eco-friendly, low cost sorbent can be applied as green, effective adsorbent in waste water remediation.

Extremely fast and high Pb2+ removal capacity using a nanostructured hybrid material

Ultra-fast toxic metal removal using a hybrid and nanostructured vaterite–poly(ethyleneimine) (NV–PEI) is reported. Especially for Pb2+, an extremely high and fast adsorption capacity without precedents is observed. Within a 3 min contact time (CT), 97–100% of Pb2+ contaminant in water samples at pH 6, with a large concentration range (from 2 to 1000 ppm) and using a dosage of 0.5 g NV–PEI per L, has been removed. The maximum adsorption capacity (qmax) calculated for a 1500 ppm Pb2+ initial concentration was 2762 mg of Pb2+ per g NV–PEI. In addition to the excellent Pb2+ removal, this material is cheap, easy to synthesize, biocompatible, and biodegradable, which makes it superior to others reported to date and an attractive alternative for the treatment of industrial wastewaters.

Adsorption of heavy-metal ions (Pb2+, Cu2+) on perm-lotion-treated human hair

Removal of toxic heavy metal ions from environmental and biological systems is important, but the use of commercially available heavy metal adsorbents is complicated by the need for specific pretreatment steps. We chose to study human hair treated with perm lotion as a heavy metal adsorbent because it is readily available and contains a large number of sulfur atoms for strong coordination to heavy metal ions. The optimal pH of adsorption by perm lotion-treated human hair was 4.16, which was slightly higher than the isoelectric point (pI) of the hair. The maximum removal ratio at pH 4.16 was 88.5% for a 50 ppm Cu2+ solution, and 96.79% for a 50 ppm Pb2+ solution. Almost 90% of the Pb2+ was removed from a 120 ppm Pb2+ solution. The perm-lotion-treated human hair was a cation-selective adsorbent.

Multifunctional system based on hybrid nanostructured rod formation, for sensoremoval applications of Pb2+ as a model toxic metal

A new and simple multifunctional system based on hybrid calcite–poly(ethyleneimine) (PEI) nanostructured rod (NR) formation, which shows as a proof-of-concept the sensing and removal (sensoremoval concept) of Pb2+ as a model toxic metal for environmental applications, has been developed. The addition of Na2CaEDTA and Na2CO3 solutions to Pb2+ contaminated water leads to the crystallization of calcite–PEI NRs. These NRs are composed of self-assembled hexagonal plate-like shapes of around 450 nm. The formed calcite–PEI NRs in suspension permit Pb2+ detection, through a simple turbidimetric measurement, and at the same time act as a Pb2+ remover. This sensing and removal system is able to detect up to 1 ppm Pb2+ (1–1000 ppm linear range) and reaches an adsorption capacity of 240 mg Pb2+ per g of NRs, as evaluated using a 342 ppm initial Pb2+ concentration at pH 4 after 30 min incubation time. The maximum Pb2+ removal capacity reported here is higher than other capacities reported previously, using materials that are not as cheap and biodegradable as calcite. The Pb2+ detection range found for this system is suitable to evaluate levels of metal contamination from industrial wastewater of around 1–100 ppm. This system based on an advanced biodegradable material constitutes a useful tool as a proof-of-concept in the design of future multifunctional platforms for the development of integrated environmental technologies with sensing and remediation functions.

Titania−Acrylic Coil Reactor for Photocatalytic Water Purification and Sterilization

A titania−acrylic composite reactor was constructed with a coil geometry. The presence of multiple titania layers within the reactor increases the titania surface area while making maximum use of the illumination provided. Both compact fluorescent blacklight (CFL) and ultraviolet light emitting diodes (LEDs) were used as illumination sources. An external pump was used to recirculate 650−800 mL of water containing organic, metallic, or bacterial contamination through the coil reactor. Complete purification of the water was achieved within 300 min with 10 ppm methylene blue, 10 ppm methyl orange, 20 ppm Pb2+, and 2200 colony forming units per milliliter (CFU/mL) of E. coli respectively using the CFL source. The effectiveness, low cost, durability, ruggedness, and energy efficiency of this reactor are advantageous for both portable and fixed-base applications.

Geochemistry and environmental impacts of retorted oil shale from Jordan

Physical and chemical characterization of spent oil shale (OS) from El-Lajjun area has been carried out and compared with the original OS. The spent shale (SS) is subjected to leaching tests to detect the possibilities of heavy metals released from it into the environment. Standard column leaching experiments have revealed no detectable release of heavy metals to the percolating water. The effectiveness of the SS in removing Pb2+ from wastewater has been investigated. The SS is very efficient in removing most of Pb2+ where 1 m3 of SS has an efficiency to remove from 64 to 94% of Pb2+ from about 1,300 m3 wastewater sample containing 50 ppm Pb2+. The efficiency decreases substantially with increasing Pb2+ concentration in the wastewater. In real situations, where Pb2+ concentration is very low (i.e., less than 5 ppm), the efficiency of the SS is expected to be 100%.

Monitoring trace amounts of lead and arsenic adsorption by x-ray absorption fine structure combined with fluorescence spectrometry

X-ray absorption fine structure combined with fluorescence spectrometry was used for the speciation of trace amounts of lead and arsenic adsorbed. The Pb2+ species were effectively adsorbed on a layered material Mg6Fe2(OH)16(CO3)·3H2O from 100 ppb–1.0 ppm test aqueous solutions. A eutectic mixture of PbCO3 and Pb(OH)2 coagulated in the case of a 1.0 ppm Pb2+ solution, and in contrast, the major species was ion-exchanged Pb2+ in the case of the adsorption from the 100 ppb aqueous solution. The arsenic species were effectively adsorbed on intercalated Fe-montmorillonite from 50 ppb–16 ppm test aqueous solutions. In this concentration range, As3+ in the solution was oxidized upon adsorption. The adsorbed structure was suggested to be [AsV(OH)2(μ-OFe)2] both in the cases of adsorption of As3+ and As5+.

Effects of crude oil spillage on growth and yield of maize (Zea mays L.) in soils of midwestern Nigeria.

The effect of crude oil spillage on growth, productivity and nutrient uptake of maize (Zea mays L.) was assessed in a pot experiment using an Evwreni manifold sample of a petroleum development company, which had a specific gravity of 0.8778. The Suwan 1 variety of maize was used in the experiment. In crude oil polluted soils, germination was delayed and the germination percentage was significantly affected by oil pollution. Growth was poor in polluted soils using parameters such as plant height, stem girth, ear height, leaf area at four weeks after planting, leaf area at maturity and average length of primary roots as growth indicators. Grain yield was significantly reduced at 95% level of probability with yield (when compared with the control) reduced by as much as 98.6%, 96.5% and 58.3% for preplant, five weeks after planting (5 WAP) and seven weeks after planting (7 WAP) treatments, respectively. Leaf analysis of the maize plants grown in soils contaminated with crude oil a week before planting (preplant treatment) revealed mean levels of heavy metals (6.18 ppm Zn2+, 0.62 ppm Cu2+, 26.24 ppm Fe2+, 10.84 ppm Mn2+, 2.96 ppm Pb2+ and 3.88 ppm Co2+) which are higher than the maximum permissible levels (MPL) for maize in tropical soils. Maize plants that were polluted at other time intervals showed no significant (p > 0.05) variation in heavy metal concentrations when compared with the control, and were considered potentially safe for human consumption.

The role of210Pb in evaluating container adsorption of Pb(II) from dilute aqueous solutions

Solutions of Pb2+ at ppb to ppm levels were tagged with210Pb and then counted from time to time over a period of one year to measure the extent of container adsorption. All count rates for samples which were acidified with HNO3 were at least 90% of their initial values, even after one year of storage. Amber glass containers proved to be superior to polypropylene for 0.1 and 1.0 ppm Pb2+ solutions; but below 0.1 ppm, polypropylene was superior. For non-acidified samples, the count rate dropped rapidly within the first two months, and then declined more gradually thereafter, with polypropylene generally superior.

Effects of γ‐ray irradiation on the properties of Pb2+ doped potassium chloride crystals

AbstractCorrelations between various properties (e.g. ionic conductivity, dislocation density, colourability, thermoluminescence, thermal recovery) of as‐received and irradiated KCl crystals containing up to about 20 mole · ppm Pb2+ are revealed. On the basis of the above data and the model proposed by MATSUNAMI et al. some speculations regarding the final irradiation product are presented.