Design of an S-scheme photo-catalyst utilizing a Cu-doped perovskite and MOF-5 for simultaneous degradation of organic pollutants under LED light irradiation: Application of EXRSM method for spectra separation and BBD-RSM modeling.

Heterojunction photo-catalysts have attracted significant attention in solar energy conversion due to their ability to reduce suppressing electron-hole pairs and improve catalytic capability. Herein, we designed an S-scheme photo-catalyst by encapsulating a Cu-doped perovskite inside the pores of MOF-5 for the first time, exhibiting excellent efficiency in a pollutant degradation process. The pristine MOF cannot act in the visible light region because of its wide bandgap. However, the encapsulation modified its bandgap and but also increased its photo-catalytic activity. Simultaneous photo-degradation of two organic contaminants, methylene blue (MB) and paracetamol (PA), was investigated to evaluate the catalytic activity of this composite. As a challenge, the UV-vis spectra of PA strongly overlapped with MB in a binary mixture preventing direct measurement of its concentration without previous separation via conventional methodologies. Hence, we used a simple and fast technique called the extended ratio subtraction method (EXRSM) to separate their absorption spectra. The statistical investigations established that it could resolve the issue of signal overlapping. Also, a statistical approach, Box-Behnken (BBD-RSM), was used to model and optimize the degradation process providing a better way to explain the effect and interactions of main parameters on degradation efficiency. Now, an empirical model for each pollutant can make a relationship between them. The photo-degradation yield was obtained at 67.12% and 87.96% for PA and MB, respectively, under optimum conditions. Furthermore, the kinetics and mechanism of reaction were investigated, and the results revealed that it follows a pseudo-first-order model for each pollutant.

Data on the environmental exposure to lead in Iran.

The data was obtained to present the environmental and occupational exposure to lead in Iranian populations based on the published articles. To acquire the data, online resources including Google Scholar, Magiran, SID, Iranmedex, PubMed, and Science Direct were searched and 104 articles were found out of which 70 that focused on the level of lead in blood, urine, milk, and hair of different Iranian populations were selected. Since the results of the studies were not homogenous, it was not possible to carry out a meta-analysis. The average blood lead level (BLL) among workers, ordinary people, patients with specific diseases, addicts, and pregnant women, women in labor, infants, and children are presented in this article. The average BLL was compared to the standards.

Synthesis of Fe3O4 Nanoparticles Modified by Oak Shell for Treatment of Wastewater Containing Ni(II).

In present study, removal of nickel ions (Ni (II)) from synthetic wastewater using Fe3O4 nanoparticles modified by oak shell was investigated. The FTIR analysis of the adsorbent suggested the occurrence of interaction between the carboxyl group on oak shell modified magnetic nanoparticles (OSMMN) surface and Ni (II). Also, the morphology and size of the adsorbent were observed by SEM and TEM. Additionally, the effect of different parameters such as contact time, adsorbent dose, solution pH and initial concentration of nickel (II) ions were investigated on the adsorption of nickel. The adsorption experiments showed that the maximum Ni(II) adsorption was obtained as contact time = 15 min, temperature = 25 °C, adsorbent dosage = 2.6 g/L, and pH = 4.5. In these conditions, 93.88% Ni(II) was removed from aqueous solution. Moreover, in order to study equilibrium behavior of adsorption, Langmuir and Freundlich isotherm models were applied. The results showed that the experimental data were fitted well with the Langmuir isotherm model, and the maximum adsorption capacity of the adsorbent using Langmuir model was determined to be 454.54 mg/g which was a considerable amount.

Design of a new integrated chitosan-PAMAM dendrimer biosorbent for heavy metals removing and study of its adsorption kinetics and thermodynamics.

In this research, different generations of PAMAM-grafted chitosan as integrated biosorbents were successfully synthesized via step by step divergent growth approach of dendrimer. The synthesized products were utilized as adsorbents for heavy metals (Pb(2+) in this study) removing from aqueous solution and their reactive Pb(2+) removal potential was evaluated. The results showed that as-synthesized products with higher generations of dendrimer, have more adsorption capacity compared to products with lower generations of dendrimer and sole chitosan. Adsorption capacity of as-prepared product with generation 3 of dendrimer is 18times more than sole chitosan. Thermodynamic and kinetic studies were performed for understanding equilibrium data of the uptake capacity and kinetic rate uptake, respectively. Thermodynamic and kinetic studies showed that Langmuir isotherm model and pseudo second order kinetic model are more compatible for describing equilibrium data of the uptake capacity and kinetic rate of the Pb(2+) uptake, respectively.

Protective effect of gallic acid isolated from Peltiphyllum peltatum against sodium fluoride-induced oxidative stress in rat's kidney.

In the present study, the nephroprotective effect of gallic acid isolated from Peltiphyllum peltatum was examined in sodium fluoride (NaF) treated rats. Nephrotoxicity was induced by 1-week intoxication of NaF at 600 ppm through drinking water. The levels of thiobarbituric acid reactive substances, reduced glutathione as well as activities of superoxide dismutase and catalase in renal tissues homogenates were determined. The serum biochemical markers of renal injuries including creatinine, serum urea, blood urea nitrogen, uric acid levels as well as the levels of phosphate and calcium were also assessed. Intoxication with NaF caused a significant increase in the levels of thiobarbituric acid reactive substances (46 % versus to control) and reduced the glutathione concentration (47 %) and the activities of superoxide dismutase (46 %) and catalase (41 %) in renal tissues homogenates. NaF intoxication also induced significant alterations in the kidney biochemical markers increasing the levels of urea, uric acid, blood urea nitrogen, creatinine, and phosphate and decreasing the levels of calcium. Daily administration of gallic acid (20 mg/kg) for 1 week before NaF intoxication brought the antioxidant-oxidant balance similar to the NaF-untreated group. Silymarin, used a standard antioxidant agent, also showed a nephroprotective activity. We concluded that NaF caused nephrotoxicity and oxidative stress in renal tissues and daily administration of gallic acid for 1 week prior to intoxication inhibited toxicity and oxidative stress.