TiO2 thin films and Ag/TiO2 nanoparticles were prepared by CVD and plasma bombardment method. XRD results showed the presence of Ag nanoparticles in TiO2 matrix. SEM image confirmed formation of Ag nanoparticles. XPS analysis was utilized to study the chemical state of the Ag/TiO2 nanostructure. Statistical surface analysis revealed that since there is a linear relation between logarithmic diagram of Cq(r) and r<Rc~4 mm for all q, both surfaces have self-affine structure. Formation of Ag/TiO2 nanoparticles led to the reduction of roughness of the samples from 0.72 nm to 0.61 nm. Ag/TiO2 nanoparticles represented greater hydrophilicity under UV illumination and visible light compared with TiO2. TiO2 thin films and Ag/TiO2 nanoparticles showed an inhibition for proliferation of the bacteria on their surfaces. Antibacterial activity of the samples contributed to the growth inhibition of the bacteria on their surfaces.

In this study, the nonlinear optical properties and optical limiting performance of the silver nanoparticles (AgNPs) in distilled water are investigated. The nonlinear absorption coefficient of the colloid is measured by the Z-scan technique. The optical limiting behavior of the AgNP suspension is investigated under exposure to nanosecond laser pulses at 532 nm. The results show that nonlinear scattering can increase the performance of the optical limiting. A theoretical analysis is suggested investigating the observed nonlinear behavior of the AgNPs. It will be shown that nonlinear light scattering occurs at high beam intensity due to induced refractive mismatch between the silver nanoparticles and water. The experimental Z-scan data is fitted with the proposed theoretical model and this has allowed extracting the values of nonlinear absorption coefficient, linear and nonlinear scattering coefficients for the AgNP suspension.

Carboxy methyl cellulose has been used to coat Ag nanoparticles to synthesized Nano solutions. FTIR and SEM methods were used to analyze the physicochemical characteristics of Nano solutions as they had been synthesized. Due to their use in medical applications, silver nanoparticles are discovered to exhibit potent antibacterial activity. By manipulating the synthetic silver nanoparticles’ size and form, antibacterial activity can be controlled. The synthetic chemicals’ antimicrobial properties carboxymethylcellulose coated (Ag) nanoparticle was also screened on various bacteria. The prepared polymer shows excellent antimicrobial activities. The findings demonstrated that together “Gram-positive as well as Gram-negative bacteria” may thrive without being hampered by nanoparticles. Compared to Gram-negative bacteria, Gram-positive bacteria were highly responsive to biogenic NPs. This is consistent with the finding that gram-positive bacteria are more vulnerable to Ag NPs coated with biogenic polymer (CMC) than gram-negative bacteria. As a consequence, it might be challenging to evaluate bacterial exposure to NPs.

Objective(s): Nanotechnology and nanoparticles are increasingly recognized for their potential applications in aerospace engineering, nanoelectronics, and environmental remediation, medicine and consumer products. More importantly is the potential for the application of silver nanoparticles (Ag NPs) in the treatment of diseases that require maintenance of circulating drug concentration or targeting of specific cells or organs the aim of this study was to investigate the possible protective role of Ag NP antioxidative biomarkers in rats. Ag NPs are used to investigate the potential risks for the environment and health.Materials and Methods: Rats received Ag NP, 5, 50, 250 and 500 mg/kg/day IP. After two week of treatment, the activity of enzymatic scavengers such as glutathione peroxidase (GPx), superoxide dismutase (SOD) and total antioxidant capacity (TAC) of blood samples were measured.Results: Ag NP in 5, 50, 250 and 500 mg/kg reduced activities of CAT, SOD and increased TAC in plasma.Conclusion: In this study, Ag NP with 500mg/kg induced activities of CAT, SOD and decreased TAC. It is concluded that antioxidative properties of Ag NP is dose dependent.

Present work investigates the capability of oxidative treatment process in the presence of nano silver doped on silicate particles for decolorization of a widely used azo dye, C. I. Direct Blue 129 (DB129) in water samples. Solutions with initial concentration of 20 mgL-1 of dye, within the range of generic concentration in textile wastewaters, were treated under ambient conditions of initial pH of 6. 7 and temperature of 25º c. The operational parameters evaluation including dye and peroxydisulfate concentration, initial pH, nanoparticles dosage and reaction time was studied in an endeavor to reach the higher dye removal efficiency. Subsequently, a removal more than 90% of dye was attained by applying the optimal operational conditions as follow: 0. 4 g of catalyst, 20 mgL-1 of dye, 5 mM of peroxydisulfate and initial pH of 6. 7 in 35 min. Moreover, kinetic study for various parameters in several conditions for treatment process was investigated. Pseudo-first-order reaction rate constants were calculated for the systems. The morphology and crystal structure of Ag-SiO2 nanoparticles were characterized by means of Transmission Electron Microscope (TEM).

More than 22% of the world's agricultural land is saline, and this trend continues to increase with climate changes. Salinity stress causes leaf color change, osmotic stress, ionic toxicity, prevents growth, photosynthesis and plant performance. Due to their size less than micron, metal nanoparticles have a great absorption and transmission power in plants. Salinity stress is a major problem in hot and dry areas under tomato cultivation. For this purpose, investigating the mutual effects of the size and type of zinc oxide and iron oxide nanoparticles on the improvement and change of growth and increasing the resistance to salt stress in tomato plants of the early urbana variety were carried out in the form of a completely randomized and factorial design with 4 replications, at a significant level of 5%. In this research, zinc oxide nanoparticles in 25 and 50 nm sizes, iron oxide in 25 nm sizes and sodium chloride in 0 and 75 mM levels were used. Nanoparticles and salinity treatments were both applied to the plants. The results showed that salt stress led to a decrease in plant growth parameters such as shoot and root length, leaf area, RWC, ion leakage. Also, NaCl led to an increase in the accumulation of prolin and other aldehydes, sodium, iron and zinc. The application of nanoparticles had a slight effect in stress-free conditions, but in stressed conditions, these two nanoparticles alone and especially in combination neutralized the effect of salinity and reduced the damage caused by salinity stress.