Interaction of ribonucleotides--namely, 5'-AMP, 5'-GMP, 5'-CMP, and 5'-UMP--with acidic, neutral, and basic alumina has been studied. Purine nucleotides showed higher adsorption on alumina in comparison with pyrimidine nucleotides under acidic conditions. Adsorption data obtained followed Langmuir adsorption isotherm, and X(m) and K(L) values were calculated. On the basis of infrared spectral studies of ribonucleotides, alumina, and ribonucleotide-alumina adducts, we propose that the nitrogen base and phosphate moiety of the ribonucleotides interact with the positive charge surface of alumina. Results of the present study may indicate the importance of alumina in concentrating organic molecules from dilute aqueous solutions in primeval seas in the course of chemical evolution on Earth.

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Chromium oxide nanoparticles (NPs) have been rapidly synthesized by precipitation method using ammomia as precipitating agent and are characterized by using X-ray Diffraction (XRD), Thermo Gravimetric Analysis (TGA), UV-Visible absorption (UV), Infrared Spectoscopy (IR), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). XRD studies show that chromium oxide NP is formed as Cr 2 O 3 and it has hexagonal structure. The shape and particle size of the synthesized Cr 2 O 3 NPs is determined by SEM and TEM. The images showed that the size of NPs of Cr 2 O 3 varied from 20 nm to 70 nm with average crystalline size 45 nm. UVVisible absorption and IR spectoscopy confirm the formation of nanosized Cr 2 O 3 . TGA verifies that the Cr 2 O 3 NPs are thermally stable upto 1000 °C.

Metal oxides/ Mixed metal oxides have wide applications as catalyst, Adsorbents, Superconductors, semiconductors, ceramics, antifungal agents and also have spacious applications in medicines. This review article is focused on their applications as photocatalyst in various organic reactions.

Zinc oxide (ZnO) nanoparticles (NPs) has been synthesized by precipitation method using ammonia as precipitating agent and ZnCl 2 . 4 H 2 O as starting material. Syntsesised nanoparticles (NPs) have been characterized by using XRD (X-ray diffraction), TGA/DTA (Thermo Gravimetric Analysis), IR (Infrared Spectroscopy), magnetic measurement, surface area measurement, SEM(Scanning electron microscopy) and TEM (Transmission electron microscopy). XRD studies show that zinc oxide was formed as ZnO and it has hexagonal structure. Magnetic measurements showed diamagnetic nature of synthesized zinc oxide NPs. Surface area of NPs zinc oxide was 4.3737 m 2 /g. The particle size of the synthesized zinc oxide was determined by TEM. TEM images show that the size of particles of ZnO varied from 27nm to 82nm with average crystallite size 50 nm.