Cadmium is considered one of the most toxic elements in the environment, with its ubiquity, a multi-organs damage and long elimination half-life. This heavy metal can pose serious health problems and ...lead to various biological disorders. Our research investigated the adverse health effects related to subchronic oral exposure at regular low- dose treatment in Ouled Djellal non- lactating ewes. The study aimed to ascertain whether the subchronic co-exposure to Cd and Pb in Ouled Djellal non- lactating ewes exacerbates the toxic effects and what are the most sensitive indicator parameters related to the blood Cd concentration. Haematological and biochemical modifications as well as the interaction with Zn and Cu were investigated. The study was conducted during two periods: in the first one, which lasted four weeks, the ewes were not contaminated: animals during this period acted as a control group and all values obtained during this period are considered as control values. Two groups of five animals were used: the Cd group received cadmium chloride orally at a dose of 2 mg/kg/day and the Cd+Pb group received cadmium chloride orally at a dose of 2mg/kg/day in addition to lead nitrate at a dose of 2.5 mg/kg/day during 9 weeks. Mean blood Cd has increased after the cadmium administration in both Cd group and Cd+Pb group. The evolution of Cd levels in the blood over time is slightly different for the Cd+Pb group. ANOVA showed a time effect (P˂0.001). The effects of treatment and animals effect were not significant (P>0.05). Disturbance in haematological and biochemical parameters was observed. The balance of the essential elements was altered; resulting in a significant decrease mainly in Cu plasma concentrations. Student's t-test indicates that toxic effects were similar for the two groups. This multi-indicator approach based on changes in different sensitive parameters can is be pertinent for risk assessment.
•Effect of crystallite nano-size on the gap energy Eg of ZnO nanopowders.•Effect of crystallite nano-size on the varistor properties.•Effect of Ga-doping on the crystallite size of ZnO ...nanopowders.•Effect of Ga-doping on the linear and nonlinear regions of (I-V)of the ZnO varistor.•The high resistance region in the linear region,also known as the "Ohmic region'.•The non-linear region is expanded, and the ability to discharge impulsive currents is greatly enhanced.
Nanostructured ZnO has received a considerable amount of interest, owing to its unique physical and chemical characteristics, as well as its remarkable performance in the fields of electronics, optics, and photonics. This work aims to study the influence of Ga dopant on the structural, optical, and electrical properties of ZnO nanopowders. Undoped and Ga-doped ZnO (GZO) nanopowders were successfully synthesised with the soft chemical sol-gel method. The solution was prepared using zinc acetate dihydrate and gallium (III) nitrate hydrate as precursors. The ethylene glycol is used as solvent. The X-ray diffractometer, scanning electronic microscope (SEM), UV–Vis, FTIR, and four-point probe method are used to analyse the properties of the synthesised powders. XRD and FTIR measurements show the growth of pure and Ga-doped ZnO crystals, which have a hexagonal wurtzite structure, and the average crystallite size varies from 9.09 nm to 24.8 nm. The nanospherical morphology of the nanopowders synthesised can be seen in the SEM images. The UV–visible spectroscopy shows that the optical gap energy increases with Ga concentration, from 3.59 eV to 3.67 eV. The I-V electrical measurements indicate that the breakdown voltage and the non-linear coefficient increase with Ga doping. This study will open the way for the investigation of a relationship between the electrical and nanostructural features of ZnO-based varistors for future device applications.
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