Production of nanoparticles from natural hydroxylapatite by laser ablation

Production of nanoparticles from natural hydroxylapatite by laser ablation

Laser ablation of solids in liquids technique has been used to obtain colloidal nanoparticles from biological hydroxylapatite using pulsed as well as a continuous wave (CW) laser. Transmission electron microscopy (TEM) measurements revealed the formation of spherical particles with size distribution ranging from few nanometers to hundred nanometers and irregular submicronic particles. High reso...

control of the optical properties of nanoparticles by laser fields

در این پایان نامه، درهمتنیدگی بین یک سیستم نقطه کوانتومی دوگانه(مولکول نقطه کوانتومی) و میدان مورد مطالعه قرار گرفته است. از آنتروپی ون نیومن به عنوان ابزاری برای بررسی درهمتنیدگی بین اتم و میدان استفاده شده و تاثیر پارامترهای مختلف، نظیر تونل زنی(که توسط تغییر ولتاژ ایجاد می شود)، شدت میدان و نسبت دو گسیل خودبخودی بر رفتار درجه درهمتنیدگی سیستم بررسی شده اشت.با تغییر هر یک از این پارامترها، در...

Photoluminescence from gas-suspended SiOx nanoparticles synthesized by laser ablation

Time-resolved photoluminescence ~PL! spectra are reported for gas-suspended 1–10 nm diameter SiOx particles formed by laser ablation of Si into 1–10 Torr He and Ar. Three spectral bands ~1.8, 2.5 and 3.2 eV! similar to PL from oxidized porous silicon were measured, but with a pronounced vibronic structure. Particle size and composition were determined with Z-contrast transmission electron micro...

Preparation and Characterization of ZnO Nanoparticles by Laser Ablation in NaOH Aqueous Solution

In the recent years, laser ablation in liquid has become an increasingly important technique for the fabrication of NPs. this paper reports our recent studies on the generation of ZnO NPs by ablation of metal targets in aqueous environments using Q-switch Nd-YAG laser (λ=532nm) immersed in NaOH (0.1M). The Surface topography studied by atomic force microscopy revealed wider size distributio...

Phosphorus cluster production by laser ablation